4,467 results on '"Peng He"'
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2. Isolated Pt Atoms Stabilized by Ga2O3 Clusters Confined in ZSM-5 for Nonoxidative Activation of Ethane
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Xiaomeng Dou, Kailang Li, Kun Zhang, Chaofeng Zhu, Debora M. Meira, Yang Song, Peng He, Liang Zhang, and Lichen Liu
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Chemistry ,QD1-999 - Published
- 2024
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3. Accelerated proton dissociation in an excited state induces superacidic microenvironments around graphene quantum dots
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Yongqiang Li, Siwei Yang, Wancheng Bao, Quan Tao, Xiuyun Jiang, Jipeng Li, Peng He, Gang Wang, Kai Qi, Hui Dong, Guqiao Ding, and Xiaoming Xie
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Science - Abstract
Abstract Investigating proton transport at the interface in an excited state facilitates the mechanistic investigation and utilization of nanomaterials. However, there is a lack of suitable tools for in-situ and interfacial analysis. Here we addresses this gap by in-situ observing the proton transport of graphene quantum dots (GQDs) in an excited state through reduction of magnetic resonance relaxation time. Experimental results, utilizing 0.1 mT ultra-low-field nuclear magnetic resonance relaxometry compatible with a light source, reveal the light-induced proton dissociation and acidity of GQDs’ microenvironment in the excited state (Hammett acidity function: –13.40). Theoretical calculations demonstrate significant acidity enhancement in –OH functionalized GQDs with light induction ( $${{\mathrm{p}}}{K}_{{\text{a}}}^{*}$$ p K a * = –4.62, stronger than that of H2SO4). Simulations highlight the contributions of edge and phenolic –OH groups to proton dissociation. The light-induced superacidic microenvironment of GQDs benefits functionalization and improves the catalytic performances of GQDs. Importantly, this work advances the understanding of interfacial properties of light-induced sp 2–sp 3 carbon nanostructure and provides a valuable tool for exploring catalyst interfaces in photocatalysis.
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- 2024
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4. Multi-dimensional cell-free DNA-based liquid biopsy for sensitive early detection of gastric cancer
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Pengfei Yu, Ping Chen, Min Wu, Guangyu Ding, Hua Bao, Yian Du, Zhiyuan Xu, Litao Yang, Jingquan Fang, Xingmao Huang, Qian Lai, Jia Wei, Junrong Yan, Shanshan Yang, Peng He, Xue Wu, Yang Shao, Dan Su, and Xiangdong Cheng
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Liquid biopsy ,Cell-free DNA ,Early detection ,Gastric cancer ,Fragmentomics ,Medicine ,Genetics ,QH426-470 - Abstract
Abstract Background Gastric cancer is the fifth most common cancer type. Most patients are diagnosed at advanced stages with poor prognosis. A non-invasive assay for the detection of early-stage gastric cancer is highly desirable for reducing associated mortality. Methods We collected a prospective study cohort of 110 stage I–II gastric cancer patients and 139 non-cancer individuals. We performed whole-genome sequencing with plasma samples and profiled four types of cell-free DNA (cfDNA) characteristics, fragment size pattern, copy number variation, nucleosome coverage pattern, and single nucleotide substitution. With these differential profiles, we developed an ensemble model to detect gastric cancer signals. Further, we validated the assay in an in-house first validation cohort of 73 gastric cancer patients and 94 non-cancer individuals and an independent second validation cohort of 47 gastric cancer patients and 49 non-cancer individuals. Additionally, we evaluated the assay in a hypothetical 100,000 screening population by Monte Carlo simulation. Results Our cfDNA-based assay could distinguish early-stage gastric cancer from non-cancer at an AUROC of 0.962 (95% CI: 0.942–0.982) in the study cohort, 0.972 (95% CI: 0.953–0.992) in the first validation cohort and 0.937 (95% CI: 0.890–0.983) in the second validation cohort. The model reached a specificity of 92.1% (128/139) and a sensitivity of 88.2% (97/110) in the study cohort. In the first validation cohort, 91.5% (86/94) of non-cancer individuals and 91.8% (67/73) of gastric cancer patients were correctly identified. In the second validation cohort, 89.8% (44/49) of non-cancer individuals and 87.2% (41/47) of gastric cancer patients were accurately classified. Conclusions We introduced a liquid biopsy assay using multiple dimensions of cfDNA characteristics that could accurately identify early-stage gastric cancer from non-cancerous conditions. As a cost-effective non-invasive approach, it may provide population-wide benefits for the early detection of gastric cancer. Trial registration This study was registered on ClinicalTrials.gov under the identifier NCT05269056 on March 7, 2022.
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- 2024
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5. Comparative study on corrosion property of 2219 aluminum alloy sheet and additively manufactured 2319 aluminum alloy
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Feng Han, Chunyang Li, Yizhou Wang, Zula Pai, Yifan Meng, Mochu Cao, Yi Liu, Peng He, Xiaoyu Ma, Long Xue, and Caimei Wang
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Aluminum alloy ,Additive manufacturing ,Microstructure ,Corrosion ,Mining engineering. Metallurgy ,TN1-997 - Abstract
2319 aluminum alloy parts was prepared by wire arc additive manufacturing technology. The corrosion properties of additively manufactured 2319 aluminum alloy and 2219 aluminum alloy sheets were systematically investigated by electrochemical tests and localized corrosion tests. The results of electrochemical tests showed that the 2219 aluminum alloy sheet has a lower corrosion current density than the additively manufactured 2319 aluminum alloy. Localized corrosion test results indicated that the additively manufactured 2319 aluminum alloy exhibited a higher intergranular corrosion depth and more severe corrosion morphology than the 2219 aluminum alloy sheet. This suggests that the 2219 aluminum alloy sheet has higher corrosion resistance than the additively manufactured 2319 aluminum alloy. The poor corrosion resistance of additively manufactured 2319 aluminum alloy could be attributed to the formation of a coarse continuous Al2Cu phase along the grain boundary. Based on this, heat treatment was used to dissolve the Al2Cu, which can effectively improve the corrosion resistance of additively manufactured 2319 aluminum alloy to the same level as that of the 2219 aluminum alloy sheet.
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- 2024
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6. Interface homogenization control and microstructural analysis of ZrC0.85 joints diffusion bonded using Nb and Ti/Nb/Ti as the interlayer
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Rui Pan, Jiayi Xu, Zhao Huang, Taoshuai Zhou, Yinghao Feng, Yihan Sun, Shujun Chen, Tiesong Lin, and Peng He
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Transition metal carbides ,Diffusion bonding ,Composite interlayer ,Microstructure ,Homogenization ,Mining engineering. Metallurgy ,TN1-997 - Abstract
Joint homogenization during transition metal carbides ceramic bonding has attracted much attention as a technique to increase the service temperature and relieve the residual stress for various high-temperature applications. In this work, homogeneous joints of ZrC0.85 ceramic were obtained by diffusion bonding using single Nb and multiple Ti/Nb/Ti as the interlayer. The effect of interlayer composition, bonding temperature and holding time on the microstructure of the joints was investigated. The effect of Nb and Ti on the composition homogeneity and the formation of Kirkendall voids in the ZrC0.85 joints was also discussed. When using single Nb as the interlayer, the homogenization of the joints can be achieved at a bonding temperature of ∼1500 °C and holding for 1 h and no Kirkendall voids were observed when further increasing the bonding temperature to 1600 °C because of the good mutual solubility of NbCx and ZrCx and the relative moderate diffusion rate of Nb. However, severe Kirkendall effects were observed at a higher temperature of 1700 °C, which would deteriorate the high-temperature performance of the joints. The adoption of Ti/Nb/Ti further minished the diffusion rate difference of the interfacial elements through the formation of TiCx phase. As a result, only a few Kirkendall voids were formed at 1700 °C. Nano-hardness of the resultant homogeneous joints was comparable to that of the ZrC0.85 ceramic due to their similar composition. This study shows that active diffusion bonding based on interlayer design for homogeneous joints could pave a new way to join transition metal carbides.
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- 2024
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7. Phosphorylation of caspase-8 by RSKs via organ-constrained effects controls the sensitivity to TNF-induced death
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Peng He, Tingting Ai, Muzhen Qiao, Zhang-Hua Yang, and Jiahuai Han
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Neoplasms. Tumors. Oncology. Including cancer and carcinogens ,RC254-282 ,Cytology ,QH573-671 - Abstract
Abstract Caspase-8 (Casp8) serves as an initiator of apoptosis or a suppressor of necroptosis in context-dependent manner. Members of the p90 RSK family can phosphorylate caspase-8 at threonine-265 (T265), which can inactivate caspase-8 for bypassing caspase-8-mediated blockade of necroptosis and can also decrease caspase-8 level by promoting its degradation. Mutating T265 in caspase-8 to alanine (A) in mice blocked TNF-induced necroptotic cecum damage but resulted in unexpectedly massive injury in the small intestine. Here, we show RSK1, RSK2, and RSK3 redundantly function in caspase-8 phosphorylation, and the duodenum is the most severely affected part of the small intestine when T265 phosphorylation of caspase-8 was prevented. Eliminating caspase-8 phosphorylation resulted in a duodenum-specific increase in basal caspase-8 protein level, which shall be responsible for the increased sensitivity to TNF-induced damage. Apoptosis of intestinal epithelial cells (IECs) was predominant in the duodenum of TNF-treated Rsk1 − / − Rsk2 − / − Rsk3 − / − and Casp8 T265A/T265A mice, though necroptosis was also observed. The heightened duodenal injury amplified systemic inflammatory responses, as evidenced by the contribution of hematopoietic cells to the sensitization of TNF-induced animal death. Further analysis revealed that hematopoietic and non-hematopoietic cells contributed differentially to cytokine production in response to the increased cell death. Collectively, RSKs emerges as a previously overlooked regulator that, via tissue/organ-constrained inactivating caspase-8 and/or downregulating caspase-8 protein level, controls the sensitivity to TNF-induced organ injury and animal death.
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- 2024
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8. A novel high-strength Al–Li alloy printed by laser powder bed fusion: Microstructural evolution and strengthenin mechanism
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Chen Wang, Shibo Wu, Zhenglong Lei, Xinrui Zhang, Weijie Fu, Xudong Li, Haoran Sun, and Peng He
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Additive manufacturing ,Al–Li alloys ,Heat treatment ,Precipitation strengthening ,Mining engineering. Metallurgy ,TN1-997 - Abstract
This paper obtained an additively manufactured high-strength Al–Li alloy by laser powder bed fusion (LPBF) based on a third generation AA2195 alloy powder raw material. The relationship between the process optimization, microstructure evolution, and mechanical properties of the as-printed (AP) and heat-treated (HT) specimens was established for the first time to explain the intergranular fracture sensibility during LPBF and reveal the dominant precipitation strengthening mechanism induced by the subsequent heat treatment. The precipitation order of AP Al–Li alloy at the last stage of the solidification process was: L (Liquid phase) →T2 (Al6CuLi3) + θ′(Al2Cu) + δ′/β' (Al3(Li,Zr)) + T (LiAlSi) + Ω (AlCuMgAg). The micro-cracks caused by a relatively high grain boundary coverage of interconnected film-like eutectic phases, as well as micro-voids caused by the localized slip between the coarse T2-phases and soft precipitate-free zones, resulted in the high intergranular fracture sensibility. The well-designed T6 heat treatment of 515 °C/60 min solution treatment and 170 °C/6 h aging treatment was conducted to maximize the precipitation strengthening by T1-phases. The precipitation order of HT Al–Li alloy was supersaturated solid solution → GP zone + δ′/β' → θ′ + T1 (Al2CuLi) + ω (Al7Cu2Fe) + β′. The presence of continuously distributed T1-cells along the grain boundaries was not only capable of providing a pinning effect on dislocations movement and boundary migration, but also able to shorten the pile-up distance on the slip plane. Such phenomena improved the resistance ability of Al–Li alloys to mechanical damage and permitted a significant strength enhancement.
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- 2024
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9. A Local Line Optimization Model for Urban Rail Considering Passenger Flow Allocation
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Peng He, Hao Tang, Feng Chen, Zijia Wang, Ying Sun, Bobo Yang, Jin Wang, and Na Li
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Urban rail transit ,Passenger flow distribution ,Local network generation ,Line optimization ,Genetic algorithm ,Transportation engineering ,TA1001-1280 ,Transportation and communications ,HE1-9990 - Abstract
Abstract It is important to strengthen the research on urban rail transit (URT) existing line renovation strategies. In this paper, we investigate the optimization of bottlenecks that are less attractive but have strong travel demand in existing URT networks. A URT local line optimization model is constructed. The maximum passenger flow and minimum project cost are chosen as the optimization objective for the benefit of both passengers and operators, and several actual constraints are considered in the proposed model, such as the station interval. In order to obtain higher computational efficiency and accuracy, a passenger flow allocation method is embedded in a genetic algorithm with elitist preservation. Taking the local network of the Beijing URT as a case study, the calculation results show that the designed algorithm can quickly and effectively obtain the optimal solution, and the generated local line scheme is able not only to meet the regional travel demand, but also to optimize the connection relationship of the existing URT network. This study can provide a reference method for increasing the attraction of URT and optimization of existing URT networks.
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- 2024
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10. Highly strengthening and toughening biomimetic ceramic structures fabricated via a novel coaxially printing
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Kunkun Song, Shengda Yang, Ningqi Shao, Yantang Zhao, Peng He, Yongfeng Wei, Hengzhong Fan, Yongsheng Zhang, and Qiangqiang Zhang
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coaxial 3d printing ,silicate ceramic composites ,enamel biomimetic microstructure ,strengthening bridge ,toughening layer ,crack deflection ,Clay industries. Ceramics. Glass ,TP785-869 - Abstract
Additive manufacturing technology, by manipulating and emulating inherent multiscale, multi-material, and multifunctional structures found in nature, has created new opportunities for constructing heterogeneous structures associated with special properties and achieving ultra-high mechanical performance and reliability in ceramic composite materials. In this study, we have developed an innovative fabrication method designated as coaxial 3D printing for the synchronous construction of two constituents into ceramic composites with a tooth enamel biomimetic microstructure. Herein, the stiff silicate and flexible epoxy served as a strengthening bridge and toughening layer, respectively. The method differed from the traditional approach of randomly dispersing reinforcing components within a ceramic matrix. It allowed for the direct creation of an internally effective three-dimensional reinforcement network structure in ceramic composites. This process facilitated synergistic deformation and simultaneous enhancement of multiple materials and hierarchical structures. Owing to the uniform distribution of internal stress and effective block of microcrack propagation, the biomimetically structured silicate/epoxy ceramic composite has demonstrated much significant enhancement in mechanical properties, including compressive strength (48.8±3.12 MPa), flexural strength (10.39±1.23 MPa), and flexural toughness (218.7±54.6 kJ/m3), which was 0.5, 2.1, and 47.5 times as high as those of the intrinsic brittle silicate ceramics, respectively. In-situ characterization and multiscale finite element simulation of microstructural evolution during three-point bending deformation further validated multiple-step features of the fracture process (silicate bridge fracture, interface detachment, epoxy extraction, and rupture), which benefited from interpenetrating structural features achieved by coaxial printing to accomplish with the complex propagating routines of the crack deflection in silicate ceramic composites. This coaxial 3D printing method paves the way for tailored toughening−strengthening designs for other brittle engineering ceramic materials.
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- 2024
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11. Coupling of biogas residue biochar and low-magnitude electric fields promotes anaerobic co-digestion of sewage sludge and food waste
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Hongbo Liu, Peng He, Yang Chen, Xingkang Wang, Ruixiang Zou, Tao Xing, Suyun Xu, Chengyang Wu, Claudia Maurer, and Eric Lichtfouse
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accelerated start-up ,biogas residue biochar ,co-digestion ,electric field ,improved methane quality ,increased methane production ,Environmental technology. Sanitary engineering ,TD1-1066 - Abstract
Biochar-assisted anaerobic digestion (AD) remains constrained due to the inefficient decomposition of complex organics, even with the direct interspecies electron transfer (DIET) pathway. The coupling of electrochemistry with the anaerobic biological treatment could shorten lengthy retention time in co-digestion by improving electron transfer rates and inducing functional microbial acclimation. Thus, this work investigated the potential of improving the performance of AD by coupling low-magnitude electric fields with biochar derived from the anaerobically digested biogas residue. Different voltages (0.3, 0.6, and 0.9 V) were applied at various stages to assess the impact on biochar-assisted AD. The results indicate that an external voltage of 0.3 V, coupled with 5 g/L of biochar, elevates CH4 yield by 45.5% compared to biogas residue biochar alone, and the coupled approach increased biogas production by up to 143% within 10 days. This finding may be partly explained by the enhanced utilization of substrates and the increased amounts of specific methanogens such as Methanobacterium and Methanosarcina. The abundance of the former increased from 4.0 to 11.3%, which enhances the DIET between microorganisms. Furthermore, the coupling method shows better potential for enhancing AD compared to preparing iron-based biochar, and these results present potential avenues for its broader applications. HIGHLIGHTS Biochar coupled with electric fields was used to enhance AD.; Coupling of biogas residue biochar and electric fields accelerated the initiation of AD.; The coupled approach improved biogas production by 143% within 10 days.; The abundance of DIET-mediated Methanobacterium was improved to 11.27%.;
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- 2024
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12. Shear damage mechanisms of jointed rock mass: a macroscopic and mesoscopic study
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Gang Wang, Wenhao Liu, Feng Jiang, Peng He, Na Huang, Zhiyong Xiao, and Chengcheng Zheng
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Cohesive element ,Shearing process ,Peak strength ,Failure type ,Medicine ,Science - Abstract
Abstract The joints are existing throughout the underground rock mass. It is of great significance to investigate the shear performance of the rock mass to maintain the stability of the underground structure. In this study, we conducted orthogonal tests to determine the proportion of rock-like materials, and used JRC curves to make specimen molds and then prepare the specimens. We conducted straight shear tests and uniaxial compression tests to determine the various mechanical parameters of the rock-like materials. Next, we carried out the compression and shear tests to investigate the shear characteristics of the specimens, and study the damage pattern and shear strength of the jointed rock mass under different confining pressures and roughness levels. The mesoscopic displacements in the shear process of joints were analyzed by using ABAQUS. The test results show that the effect of the confining pressure on the shear strength of the joint plane is relatively obvious, and a larger confining pressure indicates a larger shear strength. The effects of different joint plane roughness and shear rated on the shear characteristics of the joint plane are also significant. The mesoscopic displacement difference inside the joint plane with higher roughness is relatively large, and the stress concentration phenomenon is obvious and lasts longer, which leads to the faster destruction of the specimen with higher roughness and the higher destruction degree. Therefore, we suggest that the priority should be given to the reinforcement of jointed rock mass with high roughness during the construction to prevent sudden destabilization and failure.
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- 2024
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13. The grain refinements effect of Zn alloying on low-temperature Sn–Bi–In lead-free solder
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Sunwu Xu, Yifei Li, Xinyi Jing, Kyung-Wook Paik, Peng He, and Shuye Zhang
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Sn-Bi-In alloy ,Low-melting lead-free solder ,Microstructure ,Strengthening ,Mining engineering. Metallurgy ,TN1-997 - Abstract
As people enter the era of the IoT (Internet of Things), more and more microelectronic devices and flexible electronic devices have been developed and applied. A novel Bi–In–Sn–Zn quaternary solder system is presented, aiming at improving mechanical properties of low-melting solders for flexible electronics. The study examines the differences in the microstructure of the Sn–Bi–In ternary solders before and after the addition of the Zn element, furthermore, it analyzes the role of the Zn element in the Bi–In–Sn system. The results indicate that the Zn element partially exists in the form of a Zn phase, while the remaining portion dissolves in the eutectic structure of the Sn–Bi–In alloy. Moreover, a significantly higher amount of Zn is found to dissolve in the (In,Bi)Sn4 phase compared to the BiIn phase. The dissolved Zn element enhances the strength of the solder by increasing the lattice distortion in the (In,Bi)Sn4 phase and refining the grains of the Sn–Bi–In alloy. Subsequently, the 53Bi30In17Sn–Zn equilibrium phase diagram was obtained by CALPHAD (Calculation of Phase Diagrams) method based on thermodynamic calculation, providing new idea for the future research and development of solder used in the electronic packaging field.
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- 2024
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14. Enhancing the tensile performance of 12Cr17Mn6Ni5N steel weld joints through strengthened grinding process-induced gradient structures
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Xincheng Xie, Peng He, Jiayi Chen, Tao Zou, Yupeng Zhang, Jinrui Xiao, and Zhongwei Liang
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12Cr17Mn6Ni5N steel ,Gradient structure ,SGP ,Tensile property ,Mining engineering. Metallurgy ,TN1-997 - Abstract
This paper investigates the surface enhancement treatment of 12Cr17Mn6Ni5N steel weld joints using the Strengthened Grinding Process (SGP) and explores its effect on their surface characteristics and tensile performance. The study begins by examining the influence of different SGP durations on the weld joints' surface morphology, microhardness, and residual stress. Subsequently, the tensile properties of the SGP-treated samples are analyzed and the potential mechanisms by which SGP enhances the tensile performance of 12Cr17Mn6Ni5N steel weld joints are discussed. The results reveal that SGP treatment increases the maximum microhardness of 12Cr17Mn6Ni5N steel weld joints to 519.3 HV, marking a 109.9 % improvement as compared to untreated samples. Additionally, the samples’ surface residual stress was changed from residual tensile stress (46.5 MPa) to residual compressive stress (−1253.1 MPa). The SGP-treated samples exhibit a tensile strength of 671.43 MPa, marking an 8.51 % increase as compared to the untreated samples, while also achieving a simultaneous elongation of 16.42 %. The research demonstrates that SGP is an effective method for enhancing the tensile performance of specific mechanical components.
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- 2024
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15. Tumor diagnosis using carbon-based quantum dots: Detection based on the hallmarks of cancer
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Hang Wang, Siwei Yang, Liangfeng Chen, Yongqiang Li, Peng He, Gang Wang, Hui Dong, Peixiang Ma, and Guqiao Ding
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Tumor diagnosis ,Carbon-based quantum dots ,Hallmarks of cancer ,Cell physiology ,Structure design ,Materials of engineering and construction. Mechanics of materials ,TA401-492 ,Biology (General) ,QH301-705.5 - Abstract
Carbon-based quantum dots (CQDs) have been shown to have promising application value in tumor diagnosis. Their use, however, is severely hindered by the complicated nature of the nanostructures in the CQDs. Furthermore, it seems impossible to formulate the mechanisms involved using the inadequate theoretical frameworks that are currently available for CQDs. In this review, we re-consider the structure-property relationships of CQDs and summarize the current state of development of CQDs-based tumor diagnosis based on biological theories that are fully developed. The advantages and deficiencies of recent research on CQDs-based tumor diagnosis are thus explained in terms of the manifestation of nine essential changes in cell physiology. This review makes significant progress in addressing related problems encountered with other nanomaterials.
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- 2024
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16. Discovery of the Highly Selective and Potent STAT3 Inhibitor for Pancreatic Cancer Treatment
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Huang Chen, Aiwu Bian, Wenbo Zhou, Ying Miao, Jiangnan Ye, Jiahui Li, Peng He, Qiansen Zhang, Yue Sun, Zhenliang Sun, Chaowen Ti, Yihua Chen, Zhengfang Yi, and Mingyao Liu
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Chemistry ,QD1-999 - Published
- 2024
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17. A rapid evaluation method of blasting effect based on optimized image segmentation algorithm and application in engineering
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Peng He, Yifan Xu, Feng Jiang, Gang Wang, Zhiyong Xiao, and Chengcheng Zheng
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Blasting blocks ,Image acquisition ,Improved image segmentation algorithm ,Self-developed software ,Engineering site ,Medicine ,Science - Abstract
Abstract To quickly determine the blasting block degree and conduct an accurate and objective analysis of the tunnel blasting effect, this study has enhanced and improved upon the traditional genetic algorithm and Otsu algorithm. It has combined it with the marking watershed method and utilized ground digital acquisition to capture images of blasting debris. These images are then used in our custom-developed blasting analysis software to calculate the blasting block degree distribution and provide a quantitative analysis of blasting block degree. The research results show that the optimized image segmentation algorithm effectively improves the traditional threshold segmentation method on the poor effect of segmentation of the edge of the adherent block or the direct application of the watershed segmentation of the over-segmentation problem, to improve the segmentation accuracy based on the new segmentation technology is close to the traditional technology in terms of time. Through the self-developed software, the construction personnel in the project site to quickly obtain the blasting block degree histogram, block degree cumulative curve and other important indicators of the evaluation of the effect of blasting block degree, to provide data support for on-site construction, to assist in the modification of the blasting program, and to improve the efficiency of construction. This study realizes the rapid detection and block identification of blasting blocks, provides data support for the optimization of blasting parameters, and has good application and promotion value.
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- 2024
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18. GIS-based non-grain cultivated land susceptibility prediction using data mining methods
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Qili Hao, Tingyu Zhang, Xiaohui Cheng, Peng He, Xiankui Zhu, and Yao Chen
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Metaheuristic algorithms ,Particle swarm optimization ,Optimized extreme gradient boosting ,Environmental management ,Medicine ,Science - Abstract
Abstract The purpose of the present study is to predict and draw up non-grain cultivated land (NCL) susceptibility map based on optimized Extreme Gradient Boosting (XGBoost) model using the Particle Swarm Optimization (PSO) metaheuristic algorithm. In order to, a total of 184 NCL areas were identified based on historical records, and a total of 16 NCL susceptibility conditioning factors (NCLSCFs) were considered, based on both a systematic literature survey and local environmental conditions. The results showed that the XGBoost model optimized by PSO performed well in comparison to other machine learning algorithms; the values of sensitivity, specificity, PPV, NPV, and AUC are 0.93, 0.89, 0.88, 0.93, and 0.96, respectively. Slope, rainfall, fault density, distance from fault and drainage density are most important variables. According to the results of this study, the use of meta-innovative algorithms such as PSO can greatly enhance the ability of machine learning models.
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- 2024
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19. Crack-healing and rheological properties of high content fly ash/slag/silica fume green and sustainable cement-based materials incorporating crystalline admixture and calcium alginate biomass hydrogel
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Peng He, Feng Yu, Jianying Yu, Honglei Xie, Zhen Wang, Zhixin Yang, and Shijiang Zhang
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Self-healing mechanism ,Crystalline admixture ,Calcium alginate hydrogel ,Cement-based materials ,Rheological properties ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
Cracking is an important factor affecting the durability of concrete. Rheological properties are important performance indicators of the workability of fresh concrete. Ion chelator (CA) is one kind of crystalline admixture, which can enhance crack-healing of concrete by promoting the formation of calcium carbonate in wet environment. Calcium alginate hydrogel (CaAlg) can maintain the humidity of cementitious matrix and promote the crystallization of inorganic minerals. Therefore, in this study, CaAlg bead was prepared to further improve the crack-healing of cementitious materials containing CA. Self-healing performance was evaluated by visual crack closure and water permeability test. Rheological property was measured by rotor rheometer. Healing mechanism of cementitious materials with CA and CaAlg was analyzed. Results showed that with the increase of CaAlg dosage, yield stress and plastic viscosity of paste decreased gradually. Meanwhile, fly ash and slag reduced viscosity of pastes, while silica fume increased the viscosity of pastes. CA could evidently improve the permeability and mechanical properties of mortar, especially for slag mortar. Self-healing performance test and characterization showed that CaAlg could further enhance crack-healing process of mortar with CA, especially for pure cement and slag mortar. Microscopic testing indicates that CaAlg could induce the formation of vaterite and calcite on its surface to further improve crack-healing efficiency.
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- 2024
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20. Novel nitroxoline derivative combating resistant bacterial infections through outer membrane disruption and competitive NDM-1 inhibition
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Peng He, Sijing Huang, Rui Wang, Yunkai Yang, Shangye Yang, Yue Wang, Mengya Qi, Jiyang Li, Xiaofen Liu, Xuyao Zhang, and Meiqing Feng
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Nitroxoline ,ASN-1733 ,NDM-1 ,inhibitor ,antibiotic resistance ,Infectious and parasitic diseases ,RC109-216 ,Microbiology ,QR1-502 - Abstract
ABSTRACTNew Delhi metallo-β-lactamase-1 (NDM-1) has rapidly disseminated worldwide, leading to multidrug resistance and worse clinical prognosis. Designing and developing effective NDM-1 inhibitors is a critical and urgent challenge. In this study, we constructed a library of long-lasting nitroxoline derivatives and identified ASN-1733 as a promising dual-functional antibiotic. ASN-1733 can effectively compete for Ca2+ on the bacterial surface, causing the detachment of lipopolysaccharides (LPS), thereby compromising the outer membrane integrity and permeability and exhibiting broad-spectrum bactericidal activity. Moreover, ASN-1733 demonstrated wider therapeutic applications than nitroxoline in mouse sepsis, thigh and mild abdominal infections. Furthermore, ASN-1733 can effectively inhibit the hydrolytic capability of NDM-1 and exhibits synergistic killing effects in combination with meropenem against NDM-1 positive bacteria. Mechanistic studies using enzymatic experiments and computer simulations revealed that ASN-1733 can bind to key residues on Loop10 of NDM-1, hindering substrate entry into the enzyme's active site and achieving potent inhibitory activity (Ki = 0.22 µM), even in the presence of excessive Zn2+. These findings elucidate the antibacterial mechanism of nitroxoline and its derivatives, expand their potential application in the field of antibacterial agents and provide new insights into the development of novel NDM-1 inhibitors.
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- 2024
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21. (E)-1-(5-(Hydroxymethyl) furan-2-yl)-4,4-dimethylpent-1-en-3-one
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Zhongwei Wang, Luxiao Zhou, Peng He, and Yukun Qin
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N-acetylglucosamine ,5-hydroxymethylfurfural ,chalcone ,catalysis ,organic synthesis ,Inorganic chemistry ,QD146-197 - Abstract
This study presents a novel approach in the realm of catalytic organic synthesis by integrating biomass catalytic conversion with organic synthesis techniques. Utilizing N-acetylglucosamine as the primary feedstock, the first phase of the research involves its catalytic transformation into 5-hydroxymethylfurfural (HMF). The subsequent phase employs a condensation reaction between HMF and 3,3-Dimethyl-2-butanone to synthesize a new compound, (E)-1-(5-(hydroxymethyl) furan-2-yl)-4,4-dimethylpent-1-en-3-one. This two-step process not only demonstrates the feasibility of converting biomass into valuable chemical precursors but also exemplifies the synthesis of novel compounds through green chemistry principles. The successful execution of this methodology offers fresh insights and opens new avenues for advancements in catalytic organic synthesis, emphasizing sustainability and efficiency.
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- 2024
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22. HOXB5 promotes the progression and metastasis of osteosarcoma cells by activating the JAK2/STAT3 signalling pathway
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Qiming Ma, Xingxing Li, Huming Wang, Shenglin Xu, Yukang Que, Peng He, Rui Yang, Qiwei Wang, and Yong Hu
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HOXB5 ,Osteosarcoma ,Progression ,Metastasis ,JAK2/STAT3 pathway ,Science (General) ,Q1-390 ,Social sciences (General) ,H1-99 - Abstract
Objective: To investigate the involvement of the homeobox gene B5 (HOXB5) in the progression and metastasis of osteosarcoma. Methods: The expression of HOXB5 in human osteosarcoma tissues and its correlation with clinical indicators were investigated using bioinformatics analysis and immunohistochemical labelling. Human osteosarcoma cells (HOS, MG63, U2OS, and Saos-2) and normal human osteoblasts (hFOB1.19) were cultivated. The expression of HOXB5 in these cells was detected using western blotting (WB) and RT‒PCR. Two cell lines exhibiting elevated HOXB5 expression were chosen and divided into three groups: the blank group (mock), control group (control) and transfection group (shHOXB5). The transfection group was infected with lentivirus expressing shRNAs targeting HOXB5. The transfection efficiency was detected by WB. Cell proliferation suppression was measured by CCK-8 and 5-ethynyl-2′-deoxyuridine (EdU) assays; the percentage of apoptotic cells was determined by flow cytometry; and cell migration and invasion were detected via the Transwell chamber test. WB was utilized to determine the protein expression of genes linked to metastasis (MMP2, MMP9), apoptosis (Bax, Bcl-2), and the JAK2/STAT3 pathway (JAK2, p-JAK2, STAT3, p-STAT3). Results: In osteosarcoma tissues, HOXB5 expression was elevated and strongly correlated with distant metastasis. Silencing HOXB5 reduced the proliferation, migration and invasion of osteosarcoma cells; prevented the progression and metastasis of tumours in tumour-bearing nude mice; and reduced the activation of key proteins in the JAK2/STAT3 signalling pathway. Conclusion: Through the JAK2/STAT3 signalling pathway, HOXB5 plays a crucial role in the malignant progression of osteosarcoma and is a promising target for osteosarcoma treatment.
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- 2024
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23. Development of an Effective Relay Communication Technique for Multi-UAV Wireless Network
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Yitao Li, Ruiheng Wu, Lu Gan, and Peng He
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Unmanned aerial vehicle (UAV) ,relay communication ,real-time optimization ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
This paper proposes a novel relay algorithm to optimize the communication throughput of unmanned aerial vehicle (UAV) mobile relay formations while considering the challenges posed by obstacle avoidance, channel complexity, high dynamics of UAVs, and real-time mission requirements. To tackle the non-convex nature of this problem, we develop the unscented Kalman filter and hybrid particle swarm optimization (UKF-HPSO) algorithm. Initially, real-time prediction of the source and destination of UAV positions is accomplished using the UKF. Subsequently, these predicted coordinates serve as inputs for achieving the optimal deployment of relay UAVs under the constraints imposed by HPSO. The superiority of the UKF-HPSO algorithm compared to baseline approaches is demonstrated through extensive simulations. System throughput is effectively optimized while maintaining real-time performance by our proposed algorithm, which addresses the unique challenges of UAV communication in dynamic environments.
- Published
- 2024
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24. Investigation of the interface precipitation on α-Al(Fe,Mn)Si particles in Al–Fe–Mn–Si–Mg–Cu alloy
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Zhipeng Yuan, Yifan Lu, Zhikang Yang, Yiyou Tu, Ting Yuan, Liang Huang, Zenglei Ni, Xingxing Wang, Zili Liu, and Peng He
- Subjects
Al alloy ,Microstructure ,Interface ,Interface precipitation ,Mining engineering. Metallurgy ,TN1-997 - Abstract
The effects of particles on precipitation reactions in aluminum alloy have been widely unknown. Al–Fe–Mn–Si–Mg–Cu alloy strengthened with uniformly distributed Al(Fe,Mn)Si nanoparticles was successfully produced in this study. The alloy was then characterised using high-resolution scanning transmission electron microscopy (HRTEM), to provide a fundamental insight into the interface precipitation. Interfacial precipitations of several tens of nanometers in size was formed after aging, which were found to be Al5Cu6Mg2 and Si phases. The results demonstrated that the facetted α-Al(Fe,Mn)Si particles had a significant influence on precipitation adjacent to the α-Al(Fe,Mn)Si/Al interfaces. Semi-coherent α-Al(Fe,Mn)Si/Al interfaces were revealed to have periodically spaced misfit dislocations that are generally considered to be beneficial to heterogeneous precipitation. They not only reduce nucleation energy barriers but also act as short-circuit diffusion paths to accelerate growth rates by transporting solute atoms and vacancies.
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- 2024
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25. A low-temperature strategy to rapidly prepare high-quality diffusion-bonded joint of dissimilar superalloys enabled by pulsed current
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Jincheng Lin, Di Yu, Panpan Lin, Decai Ma, Lili Xing, Peng He, Tiesong Lin, and Weiqi Yang
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Superalloy ,Pulsed electric current ,Low-temperature diffusion bonding ,Heat treatment ,Mechanical properties ,Mining engineering. Metallurgy ,TN1-997 - Abstract
Joining of dissimilar superalloys is indispensable in the field of advanced manufacture, achieving a high-quality joint while minimizing thermal damage to substrates during diffusion bonding is a critical but challenging pursuit. A low-temperature and rapid diffusion bonding strategy enabled by pulsed current was proposed to resolve this challenge. Attributed to the enhanced interfacial plastic-deformation and carbide-precipitation, pulsed current rapidly achieved a nanovoid-free and tight joint of GH3536 and GH5188 superalloys at a low temperature of 850 °C for 5 min. Meanwhile, the rapid joining process prevented the interfacial carbides from coarsening and allowed their elimination in a short-term heat-treatment. The carbide dissolution, recrystallization of highly-deformed grain and cross-interface grain growth during heat-treatment significantly enhanced the joint performance, the heat-treated joint exhibited a high ultimate strain of 25.5 % and a tensile strength comparable to the raw GH3536.
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- 2024
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26. Effect of microwave hybrid susceptors on the interface morphology, mechanical properties and fracture morphology of Cu/nano-Sn-3.0Ag-0.5Cu/Cu joints
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Shuai Zhang, Hongzhi Zhou, Tianran Ding, Weimin Long, Sujuan Zhong, Kyung-Wook Paik, Peng He, and Shuye Zhang
- Subjects
Microwave hybrid heating ,SAC305 joints ,Susceptor ,Numerical simulation ,Mining engineering. Metallurgy ,TN1-997 - Abstract
The utilization of microwave hybrid heating in the field of low-temperature joining presents a notable benefit of delivering both selective and uniform heating, a feature that is not commonly observed in traditional welding methods. This work utilized numerical simulation to predict the heating effects of three susceptors. Furthermore, the impacts of susceptor variants on the interface morphology, mechanical properties, and fracture morphology of the Sn-3.0 Ag-0.5 Cu joint were studied. In the current study, the normal MHH technique was utilized with parameters of 900 W and 240 s to achieve successful joint production. According to the numerical simulation, the heating rate of carbon powder as a susceptor was found to be greater than that of graphite, while silicon carbide susceptor exhibited the slowest heating rate. Nevertheless, the combustion of carbon powder during the MHH process poses a potential risk to the integrity of the microwave cavity. As a result, graphite powder was selected as a more suitable susceptor. The experimental findings indicate that the shear strength of the joint with silicon carbide and charcoal as the susceptor is 75.4 % and 91.0 % of that with graphite as the susceptor, respectively. The fracture modes of the three samples with various susceptors are mixed fracture.
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- 2024
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27. Metallurgical interactions in solid/liquid diffusion couples of AA4343/AA3xxx/AA4343 layered aluminum sheet
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Zhipeng Yuan, Jiashuo Chang, Yiyou Tu, Ting Yuan, Chen Liu, Liang Huang, Zenglei Ni, Xingxing Wang, Jin Peng, Zicheng Ling, Jianjun Shi, and Peng He
- Subjects
Layered aluminum sheet ,Liquid film migration ,Stored deformation energy ,Strain induced boundary migration ,Mining engineering. Metallurgy ,TN1-997 - Abstract
The effect of pre-stretching on solid-liquid interaction, microstructure and brazing performance of AA4343/AA3xxx/AA4343 layered aluminum sheet during brazing at the atomic level (solid solution), nanoscale (dislocation) and micron level (grain boundary) are studied by glow discharge optical emission spectrometry (GDOES), scanning electron microscope (SEM), electron backscatter diffraction (EBSD) and transmission electron microscopy (TEM). The microstructure after brazing largely depends on the forming condition. The driving force of liquid film migration (LFM) is the reduction of stored deformation energy. The interaction between the liquid clad and solid core layers changes the elemental distribution and microstructure, which in turn affects the brazing performance of the sheet. The results reveal the mechanism of solid-liquid interaction of layered aluminum sheet during brazing and clarify the driving force of LFM of layered aluminum sheet during brazing. Consequently, these results provide important insights for the design and theoretical research of functional layered aluminum sheet.
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- 2024
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28. An inductive knowledge graph embedding via combination of subgraph and type information
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Hongbo Liu, Yue Chen, Peng He, Chao Zhang, Hao Wu, and Jiange Zhang
- Subjects
Medicine ,Science - Abstract
Abstract Conventional knowledge graph representation learn the representation of entities and relations by projecting triples in the knowledge graph to a continuous vector space. The vector representation increases the precision of link prediction and the efficiency of downstream tasks. However, these methods cannot process previously unseen entities during the knowledge graph evolution. In other words, the model trained on the source knowledge graph cannot be applied to the target knowledge graph containing new unseen entities. Recently, a few subgraph-based link prediction models obtained the inductive ability, but they all neglect semantic information. In this work, we propose an inductive representation learning model TGraiL which considers not only the topological structure but also semantic information. First, distance in the subgraph is used to encode the node’s topological structure. Second, the projection matrix is used to encode the entity type information. Finally, both kinds of information are fused for training to acquire the ultimate vector representation of entities. The experimental results indicate that the model’s performance has been significantly improved compared to the existing baseline models, demonstrating the method’s effectiveness and superiority.
- Published
- 2023
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29. Transforming standards into classrooms for knowledge-in-use: an effective and coherent project-based learning system
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Peng He, Joseph Krajcik, and Barbara Schneider
- Subjects
Science standards ,Learning system ,Project-based learning ,High school chemistry ,Student engagement ,Curriculum ,Theory and practice of education ,LB5-3640 ,Science - Abstract
Abstract Global science education reform calls for developing student knowledge-in-use that applies the integrated knowledge of core ideas and scientific practices to make sense of phenomena or solve problems. Knowledge-in-use development requires a long-term, standards-aligned, coherent learning system, including curriculum and instruction, assessment, and professional learning. This paper addresses the challenge of transforming standards into classrooms for knowledge-in-use and presents an iterative design process for developing a coherent and standards-aligned learning system. Using a project-based learning approach, we present a theory-driven, empirically validated learning system aligned with the U.S. science standards, consisting of four consecutive curriculum and instruction materials, assessments, and professional learning to support students’ knowledge-in-use in high school chemistry. We also present the iterative development and testing process with empirical evidence to support the effectiveness of our learning system in a five-year NSF-funded research project. This paper discusses the theoretical perspectives of developing an NGSS-aligned, coherent, and effective learning system and recaps the development and testing process by unpacking all essential components in our learning system. We conclude that our theory-driven and empirically validated learning system would inform high school teachers and researchers across countries in transforming their local science standards into curriculum materials to support students’ knowledge-in-use development.
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- 2023
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30. Mechanisms of dihydromyricetin against hepatocellular carcinoma elucidated by network pharmacology combined with experimental validation
- Author
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Shuo Zhang, Ya-Ning Shi, Jia Gu, Peng He, Qi-Di Ai, Xu-Dong Zhou, Wei Wang, and Li Qin
- Subjects
Cholesterol ,hepatocellular carcinoma cells ,lipid raft ,Therapeutics. Pharmacology ,RM1-950 - Abstract
AbstractContext Dihydromyricetin (DMY) is extracted from vine tea, a traditional Chinese herbal medicine with anti-cancer, liver protection, and cholesterol-lowering effects.Objective This study investigated the mechanism of DMY against hepatocellular carcinoma (HCC).Materials and methods Potential DMY, HCC, and cholesterol targets were collected from relevant databases. PPI networks were created by STRING. Then, the hub genes of co-targets, screened using CytoHubba. GO and KEGG pathway enrichment, were performed by Metascape. Based on the above results, a series of in vitro experiments were conducted by using 40–160 μM DMY for 24 h, including transwell migration/invasion assay, western blotting, and Bodipy stain assay.Results Network pharmacology identified 98 common targets and 10 hub genes of DMY, HCC, and cholesterol, and revealed that the anti-HCC effect of DMY may be related to the positive regulation of lipid rafts. Further experiments confirmed that DMY inhibits the proliferation, migration, and invasion of HCC cells and reduces their cholesterol levels in vitro. The IC50 is 894.4, 814.4, 467.8, 1,878.8, 151.8, and 156.9 μM for 97H, Hep3B, Sk-Hep1, SMMC-7721, HepG2, and Huh7 cells, respectively. In addition, DMY downregulates the expression of lipid raft markers (CAV1, FLOT1), as well as EGFR, PI3K, Akt, STAT3, and Erk.Discussion and conclusion The present study reveals that DMY suppresses EGFR and its downstream pathways by reducing cholesterol to disrupt lipid rafts, thereby inhibiting HCC, which provides a promising candidate drug with low toxicity for the treatment of HCC.
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- 2023
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31. Selection of isomerization pathways of multistep photoswitches by chalcogen bonding
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Shuaipeng Jia, Hebo Ye, Peng He, Xin Lin, and Lei You
- Subjects
Science - Abstract
Abstract Multistep photoswitches are able to engage in different photoisomerization pathways and are challenging to control. Here we demonstrate a multistep sequence of E/Z isomerization and photocyclization/cycloreversion of photoswitches via manipulating the strength and mechanism of noncovalent chalcogen bonding interactions. The incorporation of chalcogens and the formyl group on open ethene bridged dithienylethenes offers a versatile skeleton for single photochromic molecules. While bidirectional E/Z photoswitching is dominated by neutral tellurium arising from enhanced resonance-assisted chalcogen bonding, the creation of cationic telluronium enables the realization of photocyclization/cycloreversion. The reversible nucleophilic substitution reactions further allow interconversion between neutral tellurium and cationic telluronium and selection of photoisomerization mechanisms on purpose. By leveraging unique photoswitching patterns and dynamic covalent reactivity, light and pH stimuli-responsive multistate rewritable materials were constructed, triggered by an activating reagent for additional control. The results should provide ample opportunities to molecular recognition, intelligent switches, information encryption, and smart materials.
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- 2023
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32. Generation of Subnanometer Metal Clusters in Silicoaluminate Zeolites as Bifunctional Catalysts
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Kun Zhang, Xiaomeng Dou, Huaming Hou, Ziyu Zhou, Miguel Lopez-Haro, Debora M. Meira, Ping Liu, Peng He, and Lichen Liu
- Subjects
Chemistry ,QD1-999 - Published
- 2023
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33. The doped Pd on the crystal calculation and intermetallic property of low-temperature soldered ENEPIG substrates
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Shuye Zhang, Shaoan Wang, Shang Zhang, Xiangyu Chen, Chen Zeng, Kyung-Wook Paik, and Peng He
- Subjects
Crystal calculation ,Intermetallic property ,TEM analysis ,ENEPIG ,Hybrid solder joining ,Mining engineering. Metallurgy ,TN1-997 - Abstract
The preparation of new solder joint materials for chip packaging by designing a variety of brazing material mixes has become one of the future research directions for solder joints. They added low melting point elements to traditional solder materials to prepare low-temperature hybrid solder to meet the low-temperature packaging trend. To improve the performance of low-temperature solder, adding some alloying elements can refine the grain, change the IMC morphology and size, and improve the joint strength to a certain extent. The design of the hybrid solder joint system needs to be based on different metal pads. There are various failure modes of interconnected solder joints on different metal pads. Therefore, the interfacial response, microstructure, and mechanical properties between different hybrid solder and different metal pads need to be studied to optimize the design of the hybrid solder joint system. This paper investigated hybrid low-temperature Sn–3Ag-0.5Cu/Sn–58Bi solder joints on Au/Ni/Cu (ENIG) and Au/Pd/Ni/Cu (ENEPIG) substrates. The addition of Pd elements can change the IMC morphology of hybrid solder joints and affect the fracture failure mode of the joints under shear, with a higher average shear strength at different process parameters than ENIG welded joints. Finally, the presence form of Pd elements in the solder joints was observed under TEM and the fracture mechanism was analyzed. The results showed that Pd atoms on ENEPIG pads can replace some Cu atoms to form (Cu, Pd)6Sn5 intermetallic compounds, distorting the lattice stripe to produce distortions. And compared to ENIG pads, the IMC morphology is pin-rod-like and finer, with more complex grain boundary paths between the grains of the hybrid solder.
- Published
- 2023
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34. The design of low-temperature solder alloys and the comparison of mechanical performance of solder joints on ENIG and ENEPIG interface
- Author
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Shaoan Wang, Xiangyu Chen, Keyu Luo, Hongzhi Zhou, Rongqing Li, Peng He, Kyung-Wook Paik, and Shuye Zhang
- Subjects
SAC305/Sn58Bi ,IMC morphology ,Au/Ni/Cu pad ,Au/Pd/Ni/Cu pad ,Mining engineering. Metallurgy ,TN1-997 - Abstract
In recent years, in order to adapt to the trend of low-temperature assembly and integration, low-temperature hybrid solders with multiple elements added to the tin solder matrix have been investigated. In this regard, the morphology and size of intermetallic compounds (IMCs) are altered by adding some alloying elements, and the strength of solder joints is improved to some extent. Different pad surface treatments affect the growth of IMC, which leads to various failure modes in interconnect solder joints. Therefore, it is necessary to study the interfacial reaction, microstructure and mechanical properties of hybrid solder and different metal pads to explore the growth mechanism of IMC and the failure modes of solder joints. In this paper, mixed Sn–3Ag-0.5Cu/Sn–58Bi low-temperature solder joints on Au/Ni/Cu (ENIG) and Au/Pd/Ni/Cu (ENEPIG) substrates are investigated. The results show that the addition of palladium element can change the IMC morphology, refine the grain size of the hybrid solder joints, and affect the fracture failure mode of the solder joints under shear force. The average shear strength is significantly higher than that of solder joints with ENIG surfaces under different process parameters. Thermodynamic calculations of enthalpy change and the effect of Jackson's parameter α value on IMC morphology are also investigated in this paper. The addition of palladium elements increases the α value and is more favorable to the formation of columnar grains. This provides guidance for the grain growth of IMC in hybrid solder joints with added alloying elements.
- Published
- 2023
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35. Residual Stress Analysis in Linear Friction Welded Ti17
- Author
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Peng He, Yunxin Wu, Tao Zhang, and Junlong Jin
- Subjects
Ti17 ,linear friction welding ,residual stress ,numerical model ,prediction method ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
Residual stresses with a complex distribution are generated after linear friction welding, which affects the service performance of the weldment. In this work, a numerical model for linear-friction-welded Ti17 (Ti-5Al-2Sn-2Zr-4Mo-4Cr) was developed to investigate the evolution of residual stresses and the effect of welding parameters on residual stresses. Additionally, a method for predicting internal residual stresses was constructed. The results indicate that the residual stresses near the contact interface are largest in the oscillatory direction, peaking at ~661 MPa at 2 mm away from the contact interface. The evolution of stresses is not only related to the inhomogeneous thermal gradient, but also to the forging force. And the stress distribution essentially stabilizes within the duration of the forging force applied. Increasing the amplitude and frequency results in higher peaks of tensile residual stresses and a more concentrated distribution. Conversely, increasing the forging force only reduces the magnitude of the residual stresses. The developed prediction method, based on the similarity of internal residual stress distributions, facilitates the prediction of internal residual stresses using measured surface residual stresses.
- Published
- 2024
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36. Correction to: Transforming standards into classrooms for knowledge-in-use: an effective and coherent project-based learning system
- Author
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Peng He, Joseph Krajcik, and Barbara Schneider
- Subjects
Theory and practice of education ,LB5-3640 ,Science - Published
- 2024
- Full Text
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37. Soil nitrogen availability and microbial carbon use efficiency are dependent more on chemical fertilization than winter drought in a maize–soybean rotation system
- Author
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Wenqing Bao, Peng He, Lin Han, Xiaowei Wei, Lei Feng, Jianqin Zhu, Jihua Wang, Xuechen Yang, and Lu-Jun Li
- Subjects
ammonium availability ,Mollisol cropland ,nitrate availability ,phospholipid fatty acid analysis ,snow removal ,soil microbial characteristics ,Microbiology ,QR1-502 - Abstract
Soil nitrogen (N) availability is one of the limiting factors of crop productivity, and it is strongly influenced by global change and agricultural management practices. However, very few studies have assessed how the winter drought affected soil N availability during the subsequent growing season under chemical fertilization. We conducted a field investigation involving snow removal to simulate winter drought conditions in a Mollisol cropland in Northeast China as part of a 6-year fertilization experiment, and we examined soil physicochemical properties, microbial characteristics, and N availability. Our results demonstrated that chemical fertilization significantly increased soil ammonium and total N availability by 42.9 and 90.3%, respectively; a combined winter drought and fertilization treatment exhibited the highest soil N availability at the end of the growing season. As the growing season continued, the variation in soil N availability was explained more by fertilization than by winter drought. The Mantel test further indicated that soil Olsen-P content and microbial carbon use efficiency (CUE) were significantly related to soil ammonium availability. A microbial community structure explained the largest fraction of the variation in soil nitrate availability. Microbial CUE showed the strongest correlation with soil N availability, followed by soil available C:P and bacteria:fungi ratios under winter drought and chemical fertilization conditions. Overall, we clarified that, despite the weak effect of the winter drought on soil N availability, it cannot be ignored. Our study also identified the important role of soil microorganisms in soil N transformations, even in seasonally snow-covered northern croplands.
- Published
- 2024
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38. Straw addition and low soil moisture decreased temperature sensitivity and activation energy of soil organic matter
- Author
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Peng He, Lu-Jun Li, Shan-Shan Dai, Xiao-Li Guo, Ming Nie, Xuechen Yang, and Yakov Kuzyakov
- Subjects
Mollisols and Chernozems ,Soil warming ,Straw decomposition ,Priming effect ,Temperature-moisture interactions ,Science - Abstract
Incorporating straw into soils is an effective and cost-efficient method for sequestering organic carbon (C) and enhancing soil quality. However, the interactive effects of soil moisture and temperature on soil organic matter (SOM) mineralization have remained unclear in the presence of plant residues. We assessed the impacts of 13C-labeled maize (Zea mays) straw on SOM mineralization in two soils with contrasting soil C content (3.0 % and 6.8 %) under two moisture levels (45 % or 65 % water holding capacity (WHC)) and two temperatures (12 °C or 22 °C) through an experimental incubation. In the absence of straw addition, CO2 production at 22 °C was 2–3 times more than at 12 °C, and was 31–40 % higher at 65 % WHC than at 45 % WHC in both soils. Soil temperature and moisture interactively affected straw decomposition. After a 66-day incubation, approximately 7–11 % of straw was decomposed to CO2, contributing 44–67 % to the total CO2 production. Straw addition increased SOM mineralization across all temperature and moisture levels, resulting in a positive priming effect (PE). The highest PE was observed at 45 % WHC and 22℃ in both soils. The temperature sensitivity (Q10 value) of native SOM mineralization decreased with straw addition due to higher quality SOM (i.e., higher the basal microbial respiration rate per unit organic C at 0 °C and DOC/SOC) compared with control (no straw addition). The Q10 values of SOM and straw decomposition was higher at 65 % WHC compared to 45 % WHC, indicating that drought conditions have potential to dampen effects of temperature on the decomposition. We also discovered a positive correlation between Q10 and activation energy and a negative correlation with soil C quality, providing support for the C quality temperature hypothesis. In summary, our findings contribute to advancing our understanding of how soil C dynamics respond to exogenous C inputs under environment change.
- Published
- 2024
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39. Coaxially printed biomimetic BSPC with high strength and toughness
- Author
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Kunkun Song, Shengda Yang, Yongfeng Wei, Ningqi Shao, Peng He, Yantang Zhao, Tao Du, Hengzhong Fan, and Qiangqiang Zhang
- Subjects
Coaxial 3D printing ,Silicate-based biomimetic composite ,Interpenetrated microstructure ,Strengthening bridge ,Toughening layer ,Crack propagation ,Materials of engineering and construction. Mechanics of materials ,TA401-492 - Abstract
The trade-off between strength and toughness in traditional silicate-based materials presents a notable challenge in engineering infrastructure. The limited range of suitable components means that chemical modification does not fully address inherent brittleness. This study introduces a novel coaxial 3D printing method to create tooth enamel biomimetic composites using stiff silicate and flexible polyvinyl alcohol (PVA) as strengthening and toughening agents, respectively. Unlike standard silicate composites, this method produces an interpenetrated microstructure in which silicate and PVA maintain geometric continuity. This biomimetic structure, regulated internal stress, and crack propagation inhibition contribute to the silicate–PVA composites considerably enhanced mechanical properties, including flexural strength (10.3 MPa), ductility (4.68 %), and fracture energy (1.5±0.9×104N/m), beyond the inherent brittleness of pure silicate blocks. In situ characterization and multiscale simulation of stress distribution and deformation behavior further validated multiple toughening mechanisms. These mechanisms include silicate bridge fracture, interface detachment, and PVA rupture, along with complex cracking patterns. The significantly strengthened and toughened biomimetic silicate–PVA composite suggests promising potential for use as a structural material in engineering resilient structures.
- Published
- 2024
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40. Nutrient use efficiency has decreased in southwest China since 2009 with increasing risk of nutrient excess
- Author
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Guitang Liao, Yongdong Wang, Haiying Yu, Peng He, Zhengyu Lin, Tianfei Dai, Chenghua Xu, and Tinxuan Li
- Subjects
Geology ,QE1-996.5 ,Environmental sciences ,GE1-350 - Abstract
Abstract The optimal application of nutrients, such as nitrogen and phosphorus, to the soil is crucial for achieving high crop yields with minimal environmental impact. However, the effect of spatio-temporal changes in soil nutrient supply on crop yield is poorly understood in China. Here, we present a framework that combines environmental data, fertilizer field experiments, and machine learning to estimate the rice yield responses to different nutrient conditions and overall farmland nutrient sustainability in southwest China from 2009 to 2019. The results show that the fertilizer input has contributed to the long-term increase in rice yield over the past ten years. The fertilizer use has increased rice yield by 2.3–2.4 tons per hectare per year. However, the nutrient use efficiency decreased, with the fertilizer contribution ratio declining from 29.3% in 2009 to 27.5% in 2019. Further, 19% of the rice-growing farmlands are at risk of nutrient excess, and 36% are at risk of nutrient degradation. Controlling nitrogen and phosphorus input is key to nutrient regulation, and our approach may guide the sustainable use of nutrient resources on farmlands.
- Published
- 2023
- Full Text
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41. Effect of energy parameters on droplet transfer behavior and weld formation in laser-arc hybrid welding with cable-type welding wire
- Author
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Yuntao Chen, Zhidong Yang, Kai Xu, Peng He, Mingxiao Shi, Shujin Chen, and Chenfu Fang
- Subjects
CWW ,Laser-arc hybrid welding ,Droplet transfer behavior ,Weld formation ,Mining engineering. Metallurgy ,TN1-997 - Abstract
This paper describes the droplet transfer behavior and weld formation of laser-arc hybrid welding with cable-type welding wire (CWW). The droplet transfer behavior was photographed in real time by using a high-speed camera. The effects of energy parameters on arc morphology, droplet transfer behavior and weld formation were studied through experimental and theoretical analyses. The results show that the arc is deflected toward the laser direction, and the deflection degree increases with increasing laser power. The interaction between the laser and arc is enhanced by rotating the arc. The rotating arc enhances the interaction between plasma, the arc is more compressed and the arc volume is smaller as the welding current increases. The droplet transfer frequency increased with increasing laser power and decreased after reaching the critical value. The reaction force of metal vapor and electromagnetic force affect the droplet transfer frequency, and the maximum frequency of droplet transfer is 180.8 Hz under a laser power of 2.5 kW. The rotational force promotes molten droplet transfer and maintains the axial transition, and the welding current has a strong effect on increasing the droplet transfer frequency. The influence of laser power on weld penetration is greater than that of welding current, the weld penetration increases significantly with increasing laser power, and the cross section of the weld seam exhibits laser-arc hybrid welding characteristics.
- Published
- 2023
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42. Effect of solid solution time on microstructure and corrosion property of wire arc additively manufactured 2319 aluminum alloy
- Author
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Caimei Wang, Ziqun Jiang, Xiaoyu Ma, Yu Zhang, Peng He, and Feng Han
- Subjects
Additive manufacture ,Aluminum alloy ,Solid solution treatment ,Corrosion ,Mining engineering. Metallurgy ,TN1-997 - Abstract
2319 aluminum alloy was prepared using wire arc additive manufacturing (WAAM) technique. The solid solution time of achieving improving corrosion resistance in WAAM 2319 aluminum alloy was investigated. The results indicated that the as deposited 2319 aluminum alloy was composed of dendritic grains. Numerous inter-granular intermetallic were continuously distributed along the grain boundary. As the solid solution time increased, the inter-granular intermetallic gradually dissolved into α-Al matrix resulting in discontinuously distribution and more homogeneous element distribution. Electrochemical experiment results indicated that the corrosion potential of WAAM 2319 aluminum alloy gradually increased with the increase of solid solution time. This indicated that increasing solid solution time could effectively increased the corrosion resistance of WAAM 2319 aluminum alloy. Improved corrosion resistance can be attributed to refined and discontinuous inter-granular intermetallic.
- Published
- 2023
- Full Text
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43. Crack mechanism correlated with Sn grain orientations on Ni metal surface subjected to 1000 thermal shocks
- Author
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Xinyi Jing, Keyu Luo, Kyung-Wook Paik, Peng He, and Shuye Zhang
- Subjects
Grain orientation ,EBSD ,Solder joint ,Thermal shock test ,Nanoindentation ,Mining engineering. Metallurgy ,TN1-997 - Abstract
With the rapid development of 3D packaging, it is of great practical significance to understand the failure mechanism of solder joints in heterogeneous integration devices. In this study, the grain orientation and microstructure evolution of SAC305 solder joints were investigated in thermal shock tests for fan-out wafer level packaging. The heterogenous evolution of microstructure in Sn–3Ag-0.5Cu (SAC305) solder joints was investigated using electron backscattered diffraction (EBSD) and nanoindentation analysis. When the thermal shock reaches 1000 cycles, the local deformation caused the heterolattices in the joint to rotate toward the corners due to the thermal expansion. During deformation, sub-grain formation is accompanied by an increase in dislocations, the accumulation of plastic slip, and the activation of slip systems. The energy stored by this deformation is released in the form of cracks. The work in this paper provides new insights into the early stages of grain orientation, microstructural deformations and the accumulation of stored energy associated with these deformations, providing a scientific basis for the application and failure analysis of large size fan-out welded joints in complex working conditions.
- Published
- 2023
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44. A guide to sampling design for GPS‐based studies of animal societies
- Author
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Peng He, James A. Klarevas‐Irby, Danai Papageorgiou, Charlotte Christensen, Eli D. Strauss, and Damien R. Farine
- Subjects
animal societies ,bio‐logging ,GPS sampling ,GPS tracking ,group and collective behaviours ,group size ,Ecology ,QH540-549.5 ,Evolution ,QH359-425 - Abstract
Abstract GPS‐based tracking is widely used for studying wild social animals. Much like traditional observational methods, using GPS devices requires making a number of decisions about sampling that can affect the robustness of a study's conclusions. For example, sampling fewer individuals per group across more distinct social groups may not be sufficient to infer group‐ or subgroup‐level behaviours, while sampling more individuals per group across fewer groups limits the ability to draw conclusions about populations. Here, we provide quantitative recommendations when designing GPS‐based tracking studies of animal societies. We focus on the trade‐offs between three fundamental axes of sampling effort: (1) sampling coverage—the number and allocation of GPS devices among individuals in one or more social groups; (2) sampling duration—the total amount of time over which devices collect data and (3) sampling frequency—the temporal resolution at which GPS devices record data. We first test GPS tags under field conditions to quantify how these aspects of sampling design can affect both GPS accuracy (error in absolute positional estimates) and GPS precision (error in the estimate relative position of two individuals), demonstrating that GPS error can have profound effects when inferring distances between individuals. We then use data from whole‐group tracked vulturine guineafowl Acryllium vulturinum to demonstrate how the trade‐off between sampling frequency and sampling duration can impact inferences of social interactions and to quantify how sampling coverage can affect common measures of social behaviour in animal groups, identifying which types of measures are more or less robust to lower coverage of individuals. Finally, we use data‐informed simulations to extend insights across groups of different sizes and cohesiveness. Based on our results, we are able to offer a range of recommendations on GPS sampling strategies to address research questions across social organizational scales and social systems—from group movement to social network structure and collective decision‐making. Our study provides practical advice for empiricists to navigate their decision‐making processes when designing GPS‐based field studies of animal social behaviours, and highlights the importance of identifying the optimal deployment decisions for drawing informative and robust conclusions.
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- 2023
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45. The Soil Ecological Stoichiometry Characteristics of the Highest Latitude Areas in the Main Tea-Producing Regions of China
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Ziru Niu, Yang Zhang, Jichang Han, Yutong Zhao, Xiankui Zhu, and Peng He
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tea garden ,soil nutrients ,ecological stoichiometry ,Shanxi (province) ,Agriculture - Abstract
To investigate the contents of carbon, nitrogen, and phosphorus in tea plantation soils and their ecological stoichiometric characteristics, as well as their response to environmental factors in high-latitude regions of China, soil samples from 0 to 20 cm depth were collected from tea plantations at different altitudes and cultivation years in the main tea-producing areas of Shaanxi Province. These samples were used to determine the soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) contents and to calculate their stoichiometric ratios. The findings revealed the following: the average soil SOC and TN content in tea gardens were 13.15 and 1.30 g·kg−1, respectively, exceeding the national soil average. These values met the Class I tea garden fertility standards. However, the average soil TP content, at 0.45 g·kg−1, fell below the national soil average, meeting the Class II tea garden fertility standards. In tea gardens, the average ratios of carbon to nitrogen (C:N), carbon to phosphorus (C:P), and nitrogen to phosphorus (N:P) in the soil were 10.42, 30.98, and 3.32, respectively. These ratios were all lower than the national soil average, indicating relatively high phosphorus availability but nitrogen deficiency in tea garden soils. As altitude increased, there was a decline in soil SOC content, C N, and C P ratios, followed by a subsequent increase. No significant changes were seen in TN, TP, and N P ratio in the soil, but there was an increase in SOC content, TN content, and C P ratio during cultivation. The N-to-P ratio initially increased before decreasing, while the C-to-N ratio decreased before increasing. Soil TP content did not change significantly. The study recommends careful nitrogen fertilizer application in tea garden management to balance nitrogen and phosphorus.
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- 2024
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46. MnO2 Nanoparticles Decorated PEDOT:PSS for High Performance Stretchable and Transparent Supercapacitors
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Guiming Liu, Zhao Huang, Jiujie Xu, Tiesong Lin, Bowen Zhang, and Peng He
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supercapacitors ,MnO2 ,PEDOT:PSS ,nanoparticles ,stretchable ,transparent ,Chemistry ,QD1-999 - Abstract
With the swift advancement of wearable electronics and artificial intelligence, the integration of electronic devices with the human body has advanced significantly, leading to enhanced real-time health monitoring and remote disease diagnosis. Despite progress in developing stretchable materials with skin-like mechanical properties, there remains a need for materials that also exhibit high optical transparency. Supercapacitors, as promising energy storage devices, offer advantages such as portability, long cycle life, and rapid charge/discharge rates, but achieving high capacity, stretchability, and transparency simultaneously remains challenging. This study combines the stretchable, transparent polymer PEDOT:PSS with MnO2 nanoparticles to develop high-performance, stretchable, and transparent supercapacitors. PEDOT:PSS films were deposited on a PDMS substrate using a spin-coating method, followed by electrochemical deposition of MnO2 nanoparticles. This method ensured that the nanosized MnO2 particles were uniformly distributed, maintaining the transparency and stretchability of PEDOT:PSS. The resulting PEDOT:PSS/MnO2 nanoparticle electrodes were gathered into a symmetric device using a LiCl/PVA gel electrolyte, achieving an areal capacitance of 1.14 mF cm−2 at 71.2% transparency and maintaining 89.92% capacitance after 5000 cycles of 20% strain. This work presents a scalable and economical technique to manufacturing supercapacitors that combine high capacity, transparency, and mechanical stretchability, suggesting potential applications in wearable electronics.
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- 2024
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47. The Fractal Characteristics of Ground Subsidence Caused by Subway Excavation
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Yongjun Qin, Peng He, Jiaqi Zhang, and Liangfu Xie
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ground subsidence ,wavelet de-noising ,fractal interpolation ,fractal dimension ,deformation monitoring ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The issue of uneven ground settlement caused by the excavation of subway tunnels represents a significant challenge in the design and construction of subway projects. This paper examined the fractal characteristics of surface settlement caused by subway excavation, employing wavelet transform and fractal theory. Firstly, the noise reduction effects of different wavelet functions, decomposition levels, threshold functions, and threshold selection rules were evaluated using the SNR and RMSE. Subsequently, 291 data points were derived from 18 interpolation points through fractal interpolation, representing a utilization of only 18% of the original data, to enhance the original monitoring data information by a factor of 2.94. The average relative error between the fractal interpolation results and the monitoring data was approximately 13%, which was indicative of a high degree of accuracy. Finally, the fractal dimension of the monitoring curves under different monitoring frequencies was calculated using the box-counting method. The denoising effect of the dbN wavelet function was found to be superior to that of the symN wavelet function in the denoising process of subway construction surface deformation monitoring data. Furthermore, the hard threshold method was observed to be more effective than the soft threshold method. As the monitoring frequency decreased, the fractal dimension of the deformation curves showed an overall decreasing trend. This indicated that high-frequency monitoring could capture more details and complexity of the surface settlement, while low-frequency monitoring led to a gradual flattening of the curves and a decrease in details.
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- 2024
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48. Recent Advances in Metal–Organic Framework (MOF)-Based Composites for Organic Effluent Remediation
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Shuxian Tang, Yuxuan Wang, Peng He, Yan Wang, and Gang Wei
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two-dimensional materials ,metal–organic frameworks ,composites ,functionalization ,organic effluents ,Technology ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Microscopy ,QH201-278.5 ,Descriptive and experimental mechanics ,QC120-168.85 - Abstract
Environmental pollution caused by organic effluents emitted by industry has become a worldwide issue and poses a serious threat to the public and the ecosystem. Metal–organic frameworks (MOFs), comprising metal-containing clusters and organic bridging ligands, are porous and crystalline materials, possessing fascinating shape and size-dependent properties such as high surface area, abundant active sites, well-defined crystal morphologies, and huge potential for surface functionalization. To date, numerous well designated MOFs have emerged as critical functional materials to solve the growing challenges associated with water environmental issues. Here we present the recent progress of MOF-based materials and their applications in the treatment of organic effluents. Firstly, several traditional and emerging synthesis strategies for MOF composites are introduced. Then, the structural and functional regulations of MOF composites are presented and analyzed. Finally, typical applications of MOF-based materials in treating organic effluents, including chemical, pharmaceutical, textile, and agricultural wastewaters are summarized. Overall, this review is anticipated to tailor design and regulation of MOF-based functional materials for boosting the performance of organic effluent remediation.
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- 2024
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49. Simple and Efficient Synthesis of Ruthenium(III) PEDOT:PSS Complexes for High-Performance Stretchable and Transparent Supercapacitors
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Guiming Liu, Zhao Huang, Jiujie Xu, Bowen Zhang, Tiesong Lin, and Peng He
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supercapacitors ,ruthenium ,PEDOT:PSS ,complexes ,stretchable ,transparent ,Chemistry ,QD1-999 - Abstract
In the evolving landscape of portable electronics, there is a critical demand for components that meld stretchability with optical transparency, especially in supercapacitors. Traditional materials fall short in harmonizing conductivity, stretchability, transparency, and capacity. Although poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS) stands out as an exemplary candidate, further performance enhancements are necessary to meet the demands of practical applications. This study presents an innovative and effective method for enhancing electrochemical properties by homogeneously incorporating Ru(III) into PEDOT:PSS. These Ru(III) PEDOT:PSS complexes are readily synthesized by dipping PEDOT:PSS films in RuCl3 solution for no longer than one minute, leveraging the high specific capacitance of Ru(III) while minimizing interference with transmittance. The supercapacitor made with this Ru(III) PEDOT:PSS complex demonstrated an areal capacitance of 1.62 mF cm−2 at a transmittance of 73.5%, which was 155% higher than that of the supercapacitor made with PEDOT:PSS under comparable transparency. Notably, the supercapacitor retained 87.8% of its initial capacitance even under 20% tensile strain across 20,000 cycles. This work presents a blueprint for developing stretchable and transparent supercapacitors, marking a significant stride toward next-generation wearable electronics.
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- 2024
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50. Comparative Biomechanical Stability of the Fixation of Different Miniplates in Restorative Laminoplasty after Laminectomy: A Finite Element Study
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Guoyin Liu, Weiqian Huang, Nannan Leng, Peng He, Xin Li, Muliang Lin, Zhonghua Lian, Yong Wang, Jianmin Chen, and Weihua Cai
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biomechanics ,finite element analysis ,laminectomy ,restorative laminoplasty ,stability ,Technology ,Biology (General) ,QH301-705.5 - Abstract
A novel H-shaped miniplate (HSM) was specifically designed for restorative laminoplasties to restore patients’ posterior elements after laminectomies. A validated finite element (FE) model of L2/4 was utilized to create a laminectomy model, as well as three restorative laminoplasty models based on the fixation of different miniplates after a laminectomy (the RL-HSM model, the RL-LSM model, and the RL-THM model). The biomechanical effects of motion and displacement on a laminectomy and restorative laminoplasty with three different shapes for the fixation of miniplates were compared under the same mechanical conditions. This study aimed to validate the biomechanical stability, efficacy, and feasibility of a restorative laminoplasty with the fixation of miniplates post laminectomy. The laminectomy model demonstrated the greatest increase in motion and displacement, especially in axial rotation, followed by extension, flexion, and lateral bending. The restorative laminoplasty was exceptional in preserving the motion and displacement of surgical segments when compared to the intact state. This preservation was particularly evident in lateral bending and flexion/extension, with a slight maintenance efficacy observed in axial rotation. Compared to the laminectomy model, the restorative laminoplasties with the investigated miniplates demonstrated a motion-limiting effect for all directions and resulted in excellent stability levels under axial rotation and flexion/extension. The greatest reduction in motion and displacement was observed in the RL-HSM model, followed by the RL-LSM model and then the RL-THM model. When comparing the fixation of different miniplates in restorative laminoplasties, the HSMs were found to be superior to the LSMs and THMs in maintaining postoperative stability, particularly in axial rotation. The evidence suggests that a restorative laminoplasty with the fixation of miniplates is more effective than a conventional laminectomy due to the biomechanical effects of restoring posterior elements, which helps patients regain motion and limit load displacement responses in the spine after surgery, especially in axial rotation and flexion/extension. Additionally, our evaluation in this research study could benefit from further research and provide a methodological and modeling basis for the design and optimization of restorative laminoplasties.
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- 2024
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