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In this study, the ratio of lateral stiffness of the stilted story to that of the second story was proposed as the story stiffness ratio (SSR) to quantify vertical stiffness irregularities of hillside stilted buildings. A quasi-static experiment was conducted on a plane stilted frame with an SSR of 40 in the slope direction. Experimental results were compared with those of a stilted frame with an SSR of 1.01. The results show that SSR is an important factor influencing seismic failure modes of stilted buildings. As SSR decreases, structural ductility and deformation capacity improve, and stiffness degradation decelerates. [ABSTRACT FROM AUTHOR]

It is difficult to reach the requirement of 80% U-rib weld penetration in the practical application of single-sided welding of steel bridge panels. Meanwhile, full penetration has to be avoided. In this study, efforts are made in order to achieve fillet welds with 80% and above penetration consistently. The effect of welding parameters on the formation of single-sided U-rib fillet welds is investigated. This work has revealed that U-rib fillet weld penetration is presenting an upward trend as the welding current increases under specific welding conditions, and full penetration was observed at the current of 325 A. With the increasing distance between the filler wire and the root of the weld, the U-rib penetration reduces. As the torch angle increases during ship position welding, the U-rib penetration will first increase and then decrease. The weld formation of flat position welding is more stable and the U-rib weld penetration has been significantly improved. The optimum U-rib weld with penetration of 84.8% is achieved under the conditions of flat position welding with 285 A welding current, 44∘ torch angle, and 2mm distance between the wire and the root. [ABSTRACT FROM AUTHOR]

The Chinese Loess Plateau has undergone extensive revegetation to restore degraded land and enhance carbon sequestration. However, soil organic carbon (SOC) sequestrated in the soil profiles of deep-rooted plants has not been fully studied. Here, we investigated the SOC within a 0–23 m profile in farmlands and apple orchards converted from farmlands with different ages (A5, <5 years; A10, ~10 years; A15, ~15 years; A20, >20 years) and the controlling factors on three loess tablelands (Changwu, Qingyang, and Luochuan). The results show that SOC stocks among farmlands and orchards showed no significant difference (p = 0.88); however, SOC stocks showed a trend with tree ages, i.e., a decrease for A5 and A10 but an increase for A15 and A20. For the vertical variability, the SOC stock was the highest within 0–1 m, regardless of the standing age; however, the SOC stock in this layer only accounted for 8.8% of the total SOC stock (97.93 ± 9.18 kg m−2). Climate accounted for 82% of the variations and controlled the changes in SOC in the 0–1 m range, while soil texture dominated the SOC in the soil below 1 m, accounting for 57% of the SOC variations. The variations in SOC in the thick, unsaturated zones provide implications for future land use management and the sustainability of apple orchards in arid regions. [ABSTRACT FROM AUTHOR]

[Display omitted] Diabetic wounds are characterized by chronic trauma, with long-term non-healing attributed to persistent inflammation and recurrent bacterial infections. Exacerbation of the inflammatory response is largely due to increased levels of reactive oxygen species (ROS). In this study, catalase (CAT) was used as a biological template to synthesize nanozyme-supported natural enzymes (CAT-Mn(SH) x) using a biomimetic mineralization method. Subsequently, polymyxin B (CAT-Mn(SH) x @PMB) was immobilized on its surface through electrostatic assembly. CAT-Mn(SH) x @PMB demonstrates the ability for slow and sustained release of hydrogen sulfide (H 2 S). Finally, CAT-Mn(SH) x @PMB loaded microneedles (MNs) substrate were synthesized using polyvinyl alcohol (PVA) and hydroxyethyl methacrylate (HEMA), and named CAT-(MnSH) x @PMB-MNs. It exhibited enhanced enzyme and antioxidant activities, along with effective antibacterial properties. Validation findings indicate that it can up-regulate the level of M2 macrophages and reduce the level of pro-inflammatory cytokine tumor necrosis factor-α (TNF-α). Additionally, it promotes angiogenesis and rapid nerve regeneration, thereby facilitating wound healing through its dual anti-inflammatory and antibacterial effects. Hence, this study introduces a time–space tissue-penetrating and soluble microneedle patch with dual anti-inflammatory and antibacterial effects for the treatment of diabetic wounds. [ABSTRACT FROM AUTHOR]

In this study, the ratio of lateral stiffness of the stilted story to that of the second story was proposed as the story stiffness ratio (SSR) to quantify vertical stiffness irregularities of hillside stilted buildings. A quasi-static experiment was conducted on a plane stilted frame with an SSR of 40 in the slope direction. Experimental results were compared with those of a stilted frame with an SSR of 1.01. The results show that SSR is an important factor influencing seismic failure modes of stilted buildings. As SSR decreases, structural ductility and deformation capacity improve, and stiffness degradation decelerates. [ABSTRACT FROM AUTHOR]

Background: The demographical and geographical distributions of health resources are important aspects of healthcare access. Few studies have been published on health resource allocation in TCM hospitals in China despite public equity concerns. Methods: This article uses the Gini coefficient and agglomeration degree to analyze the health resources of TCM hospitals in China according to demographic and geographic configuration conditions in order to study the equity of the health resources of TCM from 2009 to 2018. Results: From 2009 to 2018, all regions of the TCM health resources per ten thousand people and per ten thousand square kilometers showed overall upward trends. The overall equity of the health resource allocations of TCM hospitals in China tended to improve year by year. However, there were still great differences among regions. Generally, the equity of physical resource allocation was better than the equity of human resource allocation. Additionally, the equity of health resources in TCM hospitals allocated by population was better than it was by geographic region. Conclusions: It is necessary to further optimize the structure of TCM resource allocation, and enhance the equity of resource allocation among different regions. [ABSTRACT FROM AUTHOR]

Graft‐versus‐host disease (GVHD) is a major life‐threatening complication of allogeneic hematopoietic stem cell transplantation (allo‐HSCT). Inflammatory signaling pathways promote T‐cell activation and are involved in the pathogenesis of GVHD. Suppressor of cytokine signaling 1 (SOCS1) is a critical negative regulator for several inflammatory cytokines. However, its regulatory role in T‐cell activation and GVHD has not been elucidated. Multiomics analysis of the transcriptome and chromatin structure of granulocyte‐colony‐stimulating‐factor (G‐CSF)‐administered hyporesponsive T cells from healthy donors reveal that G‐CSF upregulates SOCS1 by reorganizing the chromatin structure around the SOCS1 locus. Parallel in vitro and in vivo analyses demonstrate that SOCS1 is critical for restraining T cell activation. Loss of Socs1 in T cells exacerbates GVHD pathogenesis and diminishes the protective role of G‐CSF in GVHD mouse models. Further analysis shows that SOCS1 inhibits T cell activation not only by inhibiting the colony‐stimulating‐factor 3 receptor (CSF3R)/Janus kinase 2 (JAK2)/signal transducer and activator of transcription 3 (STAT3) pathway, but also by restraining activation of the inflammasome signaling pathway. Moreover, high expression of SOCS1 in T cells from patients correlates with low acute GVHD occurrence after HSCT. Overall, these findings identify that SOCS1 is critical for inhibiting T cell activation and represents a potential target for the attenuation of GVHD. [ABSTRACT FROM AUTHOR]

Afforestation is beneficial to improving soil carbon pools. However, due to the lack of deep databases, the variations in soil carbon and the combined effects of multiple factors after afforestation have yet to be adequately explored in >1 m deep soils, especially in areas with deep-rooted plants and thick vadose zones. This study examined the multivariate controls of soil organic carbon (SOC) and inorganic carbon (SIC) in 0–18 m deep under farmland, grassland, willow, and poplar in loess deposits. The novelty of this study is that the factors concurrently affecting deep soil carbon were investigated by multiwavelet coherence and structural equation models. On average, the SOC density (53.1 ± 5.0 kg m−2) was only 12% of SIC density (425.4 ± 13.8 kg m−2), with depth-dependent variations under different land use types. In the soil profiles, the variations in SOC were more obvious in the 0–6 m layer, while SIC variations were mainly observed in the 6–12 m layer. Compared with farmland (SOC: 17.0 kg m−2; SIC: 122.9 kg m−2), the plantation of deciduous poplar (SOC: 28.5 kg m−2; SIC: 144.2 kg m−2) increased the SOC and SIC density within the 0–6 m layer (p < 0.05), but grassland and evergreen willow impacted SOC and SIC density insignificantly. The wavelet coherence analysis showed that, at the large scale (>4 m), SOC and SIC intensities were affected by total nitrogen-magnetic susceptibility and magnetic susceptibility-water content, respectively. The structural equation model further identified that SOC density was directly controlled by total nitrogen (path coefficient = 0.64) and indirectly affected by magnetic susceptibility (path coefficient = 0.36). Further, SOC stimulated the SIC deposition by improving water conservation and electrical conductivity. This study provides new insights into afforestation-induced deep carbon cycles, which have crucial implications for forest management and enhancing ecosystem sustainability in arid regions. [Display omitted] • Soil organic and inorganic carbon varied with land use types and soil depths. • Combined effects of multiple factors on soil carbon were studied at various scales. • Magnetic susceptibility increased the coherence between SOC and total nitrogen. • Water content increased the coherence between SIC and magnetic susceptibility. • We revealed the internal relationship between soil organic and inorganic carbon. [ABSTRACT FROM AUTHOR]

[Display omitted] • The microstructure and mechanical anisotropy of additively manufactured CoCrNi medium-entropy alloys were studied after HIP and UIT. • HIP induces the formation of large number of Cr 2 O 3 particles, and transformation of LAGBs into HAGBs. • UIT contributed to the increase in the number of LAGBs and induced the transformation of columnar grains to equiaxed grains, thus decreasing the anisotropy of AM CoCrNi MEAs. The anisotropy properties of samples in different direction is found in additively manufactured (AM) CoCrNi medium-entropy alloys (MEAs). In this study, the laser direct energy deposition AM CoCrNi MEAs have been subjected to two alternative processing methods: hot isostatic pressing (HIP) and ultrasonic impact treatment (UIT). The effect of HIP and UIT on the microstructure, grain orientation, grain boundary distribution, phase distribution and mechanical properties of AM CoCrNi MEAs were systematically studied. The results show that HIP decreased the partial mechanical anisotropy of AM CoCrNi MEAs, and YS was significantly reduced. The main reason is that the HIP induces the formation of large number of Cr 2 O 3 particles, and transformation of low-angle grain boundaries (LAGBs) into high-angle grain boundaries (HAGBs). Surprisingly, both the yield strength (YS) and ultimate tensile strength (UTS) of the AM CoCrNi MEAs were increased when the UIT was added after every laser deposition of one layer (UIT-1). This is due to the combined effect of quasi-static loading and ultrasonic oscillations of UIT, which results in the dislocation multiplication and the formation of a large number of substructures. In addition, the above strengthening phenomena also lead to decrease partial mechanical anisotropy of AM CoCrNi MEAs. [ABSTRACT FROM AUTHOR]

Protein synthesis and semisynthesis offer immense promise for life sciences and have impacted pharmaceutical innovation. The absence of a generally applicable method for traceless peptide conjugation with a flexible choice of junction sites remains a bottleneck for accessing many important synthetic targets, however. Here we introduce the PALME (protein activation and ligation with multiple enzymes) platform designed for sequence-unconstrained synthesis and modification of biomacromolecules. The upstream activating modules accept and process easily accessible synthetic peptides and recombinant proteins, avoiding the challenges associated with preparation and manipulation of activated peptide substrates. Cooperatively, the downstream coupling module provides comprehensive solutions for sequential peptide condensation, cyclization and protein N/C-terminal or internal functionalization. The practical utility of this methodology is demonstrated by synthesizing a series of bioactive targets ranging from pharmaceutical ingredients to synthetically challenging proteins. The modular PALME platform exhibits unprecedentedly broad accessibility for traceless protein synthesis and functionalization, and holds enormous potential to extend the scope of protein chemistry and synthetic biology. [ABSTRACT FROM AUTHOR]

Reinforced concrete (RC) split-foundation frame structures are widely used in mountainous areas. There are two grounding terminals with different heights in the split-foundation frame structures. Under the earthquake, the local damage phenomenon of the structures is severe due to the uneven stiffness distribution. It is one way to improve the seismic performance of the split-foundation frame structures to install steel braces in the upper embedding floor. According to the deformation characteristics of the upper embedding floor, three types of steel braces arrangement for the split-foundation frame structures were proposed: horizontal braces, V-type braces, and V- type + horizontal braces. Then based on the ratio of lateral stiffness of steel braces and concrete frame columns, the section of steel brace was designed. A quasi-static test was carried out to analyze the influence of steel braces on the failure mode of the RC split-foundation frame. The reasonable seismic waves were selected to carry out the nonlinear dynamic time history analysis. Then the seismic response and failure mode of the split-foundation frame structures with different braces arrangements were compared. On this basis, fragility analysis was carried out, and the earthquake-induced collapse resistance capacity of split-foundation frame structures with steel braces was preliminarily evaluated. The results show that the horizontal steel brace can improve the phenomenon of damage concentration of the split-foundation frame structures. Furthermore, setting V-shaped braces can significantly reduce the damage degree of the upper embedding end columns and change the phenomenon of locally severe damage of the split-foundation frame structures. Moreover, according to the design method proposed in this paper, setting steel braces can improve the seismic collapse resistance capacity of the split-foundation frame structures. [ABSTRACT FROM AUTHOR]

"The Party leads the army," "the Party controls the army," and "the Party commands the gun" are the political principles and institutional designs of the Chinese Communist Party's leadership of the army, which emphasize that the army must follow the leadership of the Party, carry out the political tasks set by the Party, and defend the key interests of the Party. After the outbreak of the all-out War of Resistance against Japan, the Eighth Route Army, under the Party's strategic guidance, marched toward the Taihang mountains. The army helped the local Party organizations there to recover and develop, while the local Party organizations helped the army to fight and to enlarge its forces. The coordination and cooperation of the local Party organizations and the army together established the basis of the political-military configuration of the Taihang Base Area and put into effect the strategic intentions of the Party. When the Base Area entered into the consolidation-and-development stage 发展巩固阶段 , however, signs of discoordination emerged. In this special political situation, in order to ensure the smooth progress of the war against Japan, the Chinese Communist Party further ironed out the Party-army relationship by organization-building (for both Party central and local and military branches) and fighting against Guomindang reactionaries and the Japanese invaders and their puppet government. Particularly, the Party continued political training for the army to make sure that it remained under the absolute leadership of the Party. By uniting the army and the local Party organizations to implement the political lines and concrete policies of the Party central, a unified configuration of leadership in the Taihang Base Area was established, the Party, the army, and the people all united as a whole, and the Chinese Communist Party earned tremendous support for the war against Japan. This process involved at once the relationships between the Party central and the army 中央与军队 , between the military Party branches and the army 军队党与军队 , and between the local Party branches and the army 地方党与军队 , and it was an arduous journey rather than an easy walk. 摘要: "以党领军""以党统军""党指挥枪"是中国共产党领导军队的政治原则和制度设计，即军队必须服从于党的领导意志、执行党的政治任务、维护党的核心利益。全面抗战爆发之后，在中共中央战略指导下，八路军挺进太行山区，助力了地方党组织的恢复与发展，地方党则协助军队作战与扩大武装，两者相互配合，奠定了太行根据地创建的政治军事组织基础，实现了中央战略意图的落地生根。根据地进入巩固与发展时期，军队内部及军队与地方党之间出现些许消极现象。在特殊政治环境下，为确保抗战事业顺畅，中共以对党组织（含中央党、地方党、军队党）的建设及与国民党顽固派、日伪敌对势力的斗争，进一步理顺了党军关系。其中，不断强化的军队政治工作以持续发力的政治训练，保障了党（中央及军队党）对军队的绝对领导地位。同时，军队与地方党团结协力贯彻中央路线与政策，太行根据地党的"一元化"领导的基本组织架构得以确立，党政军民同心同力结为一体，中共由此获得源源不断的抗战动力支持。当然，这一过程关涉中央与军队、军队党与军队及地方党与军队三重关系维度，完成并非一蹴而就，经历了不少繁难曲折。 [ABSTRACT FROM AUTHOR]

The cultivation of deep-rooted vegetation greatly alters the tradeoffs between water and carbon dynamics, yet their impact on microbial carbon sequestration (MCS) remains inadequately documented, particularly in thick vadose zones. This information is crucial for global climate mitigation and ecosystem service enhancement. As such, we collected triplicate samples for each land use type, exploring the abundance and structure of cbbL -harboring microbial communities within 10-m deep profiles under cultivated farmland and two apple orchards of varying ages (n = 72). Our findings indicated a shift from water-dominated (improved water retention at the expense of reduced carbon sequestration) to carbon-dominated benefits (enhanced carbon sequestration at the expense of decreased water retention) in deep soil layers (2–10 m) after the transformation from farmland to apple orchards. Despite the lack of significant differences among the three land use types, the gene abundances and microbial diversity indices reduced with soil depths because of variations in substrates, resources, and microenvironments. The cbbL -harboring microorganisms consisted of 5 phyla, 7 classes, 19 orders, 30 families, and 55 genera, with Proteobacteria as the predominant bacterial phylum. The relative contributions of different genera varied with soil depths, reflecting their distinct survival strategies. The microbial network was positively connected in various soil layers under farmland and apple orchards. Furthermore, the results of correlation, redundancy analysis, and structural equation modeling jointly indicated that plant roots and soil properties, including total nitrogen and organic carbon, governed MCS processes in deep unsaturated zones. Specifically, the low microbial variation between farmland and apple orchards can be attributed to the predominant effects of climatic and pedogenic factors on soil properties, the restricted contribution of plant roots to soil nutrient levels per unit depth, and the adverse effects of plant-induced ecohydrological consequences on root systems and microbial populations. This study offers new insights within thick vadose zones containing deep-rooted plants, thereby contributing to a better understanding of global terrestrial carbon cycle processes. [Display omitted] • Microbial carbon sequestration processes were explored in 10-m deep profiles. • The farmland-to-apple orchards conversion led to water-carbon tradeoffs. • Microbial carbon sequestration differed with depths rather than land use types. • Depth-dependent plant roots and soil nutrients affects carbon sequestration. [ABSTRACT FROM AUTHOR]

The water and organic carbon stored within unsaturated zones are crucial in terrestrial ecosystems; however, the coupling effects of deep soil water and organic carbon are still poorly documented. To explore the water-carbon coupling effects within soils under tree plantations, we investigated the water and organic carbon content to 20 m deep under cultivated farmland and orchards with apple trees of varying ages (5, 10, 15, 20, and 24 years) in the loess-covered region of China. A conditional process model was used to explore the impacts of vegetation and edaphic factors on the water-carbon coupling processes. Compared with farmland, young apple orchards (0–10 years) showed lower water deficit, but the soil water storage reduced by 21%− 32% under old apple orchards (15–24 years). The organic carbon content exhibited negligible variation among apple trees of different ages. However, the water-carbon coupling effects varied with apple tree ages. A positive correlation existed between water storage and organic carbon density under young apple orchards (p < 0.05), but a negative correlation was found between water deficit and organic carbon sequestration under old apple orchards (p < 0.01). The conditional process model suggested that the water-carbon coupling relationship under young apple orchards was primarily controlled by clay content due to lower root biomass, while that under old apple orchards was concurrently shaped by silt content and coarse roots because of the developed root system of apple trees. This study offers novel insights into the sustainable management of agriculture and tree plantations in regions with deep-rooted vegetation and thick unsaturated zones. [Display omitted] • We analyzed water and carbon coupling effects within 0–20 m under apple orchards. • Apple trees triggered large water deficit but little organic carbon variation. • Soil texture led to positive water and carbon effects under young apple orchards. • Plant root caused negative water and carbon effects under old apple orchards. [ABSTRACT FROM AUTHOR]

The emergence of CoCrNi medium-entropy alloys (MEAs) holds great promise for applications in extreme service environments. However, fabricating CoCrNi MEA with an extraordinary combination of strength and ductility is urgently needed. Herein, we adopt a combination of laser direct energy deposition (L-DED) additive manufacturing and ultrasonic impact treatment (UIT) to fabricate CoCrNi additive parts. The optical microscopy results showed that the proportion of equiaxed crystals increased from 7.2% to 42.1% after UIT, while the proportion of columnar crystals with grain sizes greater than 31 μm decreased from 62.8% to 27.4%. The tensile test results at 298 and 77 K showed that the tensile strength increased by 7.0% and 27.6%, respectively, after UIT. Electron backscatter diffraction (EBSD) results indicated that the texture intensity of the XOY and XOZ planes in the additive parts decreased after UIT. The transmission Kikuchi diffraction (TKD) results showed that 29.9% of the FCC phase transformed into the HCP phase after the tensile test. Meanwhile, the volume fractions of the substructured, recrystallization, and deformation zones in the phase transformation zone and in the FCC structure were 21.2%, 58.7%, and 20.1% and 67.7%, 9.0%, and 23.3%, respectively. The enhanced transformation-induced plasticity effect contributed to the higher strength and ductility of the CoCrNi MEA treated by UIT. • The 77 K tensile test results of CoCrNi additive parts indicate the tensile strength increased 27.6% after inter-layer ultrasonic impact treatment. • Transmission Kikuchi Diffraction result exhibits 29.9% percentage of FCC phase transformed into HCP phase after tensile test. • The enhanced transformation induced plasticity effect contributes to the higher strength and ductility of the UIT CoCrNi MEA. [ABSTRACT FROM AUTHOR]

The manufacture of biofuels from cellulose is regarded as one of practicable strategies to meet increasing energy demand and alleviate environmental issues. Cellulases, which play an important role in the production of second-generation biofuels, are expected to be highly thermostable, halostable and organic solvent-stable to adapt to the harsh conditions in practical application. Here we cloned and characterized a novel cellulase (MaCel) from Mahella australiensis 50-1 BON, an anaerobic thermophile isolated from an oil reservoir. MaCel exhibited excellent thermostability, halostability as well as organic solvent stability, and could be efficiently produced in a yield of 1.7 × 106 U/L in 15 h with inexpensive culture medium. These results indicate that MaCel may be a suitable candidate for industrial applications, illustrating the potential benefits of enzymes from oil reservoir extremophiles in the manufacture of biofuels. Unlabelled Image [ABSTRACT FROM AUTHOR]

The design of multistrain systems has markedly expanded the prospects of using long biosynthetic pathways to produce natural compounds. However, the cooperative use of artificially engineered microbes to synthesize xenobiotic chemicals from renewable carbohydrates is still in its infancy. Here, a microbial system is developed for the production of high‐added‐value N‐heterocycles directly from glucose. Based on a retrosynthetic analysis, eleven genes are selected, systematically modulated, and overexpressed in three Escherichia coli strains to construct an artificial pathway to produce 5‐methyl‐2‐pyrazinecarboxylic acid, a key intermediate in the production of the important pharmaceuticals Glipizide and Acipimox. Via one‐pot tandem collaborations, the designed microbes remarkably realize high‐level production of 5‐methyl‐2‐pyrazinecarboxylic acid (6.2 ± 0.1 g L−1) and its precursor 2,5‐dimethylpyrazine (7.9 ± 0.7 g L−1). This study is the first application of cooperative microbes for the total biosynthesis of functionalized N‐heterocycles and provides new insight into integrating bioretrosynthetic principles with synthetic biology to perform complex syntheses. [ABSTRACT FROM AUTHOR]

In this paper, AISI 316L stainless steel part is obtained by laser metal deposition additive manufacturing method. The microstructure of the part was observed and analyzed by an optical microscope. The tensile mechanical properties and residual stress distribution of the part were tested by tensile test and the contour method. The results show that the bulk structure is mainly columnar crystal and equiaxed crystal, and the latter layer of laser metal deposition will form a remelted zone and heat-affected zone in the former deposition zone. Tensile test results show that the tensile strength of tensile specimens parallel to laser scanning direction and perpendicular to laser scanning direction is basically the same, but the elongation of the specimens perpendicular to the laser scanning direction is relatively better. The main reason is the different distribution characteristics of columnar crystals and equiaxed crystals in the two directions. Relatively large deformation occurs on the cut surface of the specimen after low-speed wire cut. The residual stress test results indicate that tensile stress is formed in the upper part and it reaches 315 MPa at the top surface. And compressive stress is formed at the part/substrate interface and the substrate. [ABSTRACT FROM AUTHOR]

Three-dimensional analyses of optical aberrations of metasurface flat lenses are presented via ray tracing. The ray tracing is performed on the basis of anomalous refraction/reflection law specialized for metasurface instead of conventional Snell law. Relationship between spherical aberration and working distance, feature of chromatic aberration, astigmatism in meridian, and sagittal directions are analyzed numerically to fully reveal the aberration characteristics. Through the curve descriptions of geometric point spread function (PSF) and the modulation transfer function (MTF), the influence of monochrome aberration on the metasurface flat lenses is fully demonstrated. The results of the design model are instructive for the application of the metasurface flat lense–based high quality optical systems theoretically. [ABSTRACT FROM AUTHOR]

In order to obtain a laser-cladded coating with no cracking and good corrosion resistance, this paper investigated laser cladding of a mixture of 17-4PH stainless steel and Ni60 powders on ASTM 1045 steel substrate. The surface cracking, mechanical properties and corrosion resistance of the coatings were assessed by various characterization methods. The experimental results demonstrated that a crack-free coating can be obtained by adding 30% (or above) 17-4PH stainless steel into Ni60 alloy. The mechanical properties of the coatings were determined by adding 17-4PH, but stabilized at about 79% of pure Ni60 alloy, which is acceptable considering the benefit of elimination of surface cracking. Decrease in the mechanical properties were caused by the dilution of the strengthening elements and reduction of population of hard phases. Composite coating having 30% of 17-4PH also exhibited the smallest corrosion current, lowest corrosion potential and slowest corrosion rate, and therefore the best corrosion resistance. [ABSTRACT FROM AUTHOR]

Esophageal carcinoma, with a increasing incidence, is one of the most aggressive carcinomas in gastrointestinal tract. Epidemiologic studies demonstrate an association of oral pathogens with multiple diseases, including rheumatoid arthritis, cardiovascular diseases, diabetes, and gastrointestinal malignancies. Nevertheless, a causal relationship between oral pathogens and esophageal squamous cell carcinoma (ESCC) has not been elucidated. Here, we found that Porphyromonas was significantly enriched in the saliva of patients with ESCC, compared with that in normal human. In vitro studies showed that Porphyromonas gingivalis (P. gingivalis) promoted the proliferation and motility of ESCC cells, as evidenced by up regulated expression of key molecules implicated in NF-κB signaling pathway. These findings, for the first time, demonstrated a role of oral pathogens in inducing ESCC tumorigenesis and metastasis, which might involve regulation of NF-κB signaling pathway. [ABSTRACT FROM AUTHOR]

The absence of a bonding medium is the principal problem of immiscible Mg/Fe system. Obtaining an interface layer at the Mg/steel interface is the key to achieving a metallurgical bonding. However, the type and thickness of the interface layer has a random nature during the welding process of Mg/steel dissimilar metals, which has a large impact on the joint properties. An effective AZ31 Mg alloy/22MnB5 steel joint with 12 μm width Fe 2 Al 5 interface layer is bonded by pinless friction stir spot welding, and obtained maximum shear strength 1.4 kN. In addition, a specific type and thickness of Fe 2 Al 5 intermetallic compound was chosen as the interface layer in this study. Nano-scale Fe 2 Al 5 interface layer prepared by magnetron sputtering method, which achieved a large improvement in Mg/Fe 2 Al 5 coated steel properties with a maximum shear strength 2.4 kN. The shear strength of the Mg/Fe 2 Al 5 coated steel joint was improved by 86.8% after the interface layer thickness was changed from the micron scale to the nanoscale. Nanoscale Fe 2 Al 5 amorphous-nanocrystalline interface layer was contribute to its higher shear strength. The following orientation relationship exists for the Fe 2 Al 5 /steel part of the region, (110) Fe2Al5 //(101) α-Fe. This study investigated the effect of the mixed structure of nanocrystalline and amorphous interface layers on the interfacial bond strength besides the analysis of nanostructured interface layers. The molecular dynamics simulation indicates that as the thickness of the η-Fe 2 Al 5 interface layer decreases, the stress of the α-Mg/η-Fe 2 Al 5 /α-Fe model tends to increase and then decrease. [Display omitted] • The preparation of composition-specific (Fe 2 Al 5) and nanoscale film was achieved by magnetron sputtering method. • A novel amorphous-nanocrystalline interface nanostructure was found to bond immiscible Mg/Fe dissimilar metals. • The shear strength of the Mg/Fe 2 Al 5 coated steel joint was improved by 86.6% after nanoscale interface layer obtained. [ABSTRACT FROM AUTHOR]

In this study, in order to achieve a better understanding of the strengthening mechanism in the commercially pure (CP) Ti welds, autogenously laser beam and laser-MIG hybrid welding of 4.2 mm thick CP-Ti plates were performed and the correlation between microstructure, texture distribution and the mechanical properties were systematically investigated. Microstructural coarsening and increase in microhardness were observed in the HAZ and WZ. The tensile test results suggested the base metal was the weak point of the joint for both welding conditions. The EBSD observations confirmed that a large number of 101¯2 and 112¯2 twin grains occurred in the HAZ and WZ of both welded joints, while a higher concentration of these twin grains were found in the laser-MIG hybrid joints. High concentration of the twin grain boundaries can act as barrier to stop dislocation slip during deformation and therefore contribute to the strengthening of the welds. The existence of very small twin grains and acicular α phase in HAZ and WZ would equivalently reduce the averaged grain size and therefore induce an increase in strength based on Hall-Petch's law. In addition, the averaged Schmid factor of BM is higher than that of the WZ and HAZ in both welding joints suggesting that the grain boundary sliding will take place preferably in BM during deformation so that the necking and fracture occurred in base metal during tensile tests of both welding joint specimens. [ABSTRACT FROM AUTHOR]

Joining of super duplex stainless steel (SDSS) is still a challenge, in particular, the need to control the phase balance in the weld metal. In this paper, laser-MIG hybrid welding process was used to join SAF 2507 SDSS plates. The effects of welding parameters on weld appearance, microstructure and phase distribution and mechanical properties were studied systematically. Results showed that the arc/laser hybrid effect was more significant when the arc led the laser with 2 mm distance. It was indicated that arc current mainly affected the weld width while laser power mainly affected weld penetration depth. The composition and microstructure varied a lot at different positions in the weld due to the differences in peak temperature and cooling rate. From top to root, the content of ferrite phase increased and austenite phase decreased. With optimized welding parameters, due to the increase of heat input and the introduction of welding wire, the ferrite/austenite phase balance in the weld metal was obtained. Mechanical property tests showed that the joints exhibited higher tensile strength but lower toughness compared to base metal. [ABSTRACT FROM AUTHOR]

A Ni–Fe–B–Si–Nb amorphous alloy was deposited on a steel substrate surface via a laser cladding process, and a laser cladding plus laser remelting process. The wear behavior of the laser processed samples and the bulk metallic glass (BMG) sample with the same nominal composition were tested using a pin-on-disc type testing machine. The nano-mechanical properties of the samples were measured with a nano-characterization system. The friction wear tests showed that deep grooves and wear debris were formed on the worn surface of the laser cladded coating, while only shallow grooves for the laser remelted coatings. The friction coefficients of laser remelted coatings and BMG were lower than the laser cladded coating. The wear mass losses of the laser remelted coating were less than the BMG when the laser remelting scanning speed was higher than 6 mm/min. The nano-hardness and elastic modulus of the remelted coating is higher than that of the laser cladded coating. Also, they increase with the increasing laser scanning speed with 1227.9 HV and 277.4 GPa when the remelting scanning speed is 8 m/min. Based on the nano-indentation and friction wear tests results, it was found that the friction wear properties of the laser cladded coating, laser remelted coatings and BMG related well to the ratio of H3/E2. A higher value of H3/E2 can lead to a better wear resistance property. [ABSTRACT FROM AUTHOR]

Noble metal decorated biological materials were applied to surface-enhanced Raman scattering (SERS), which have been widely used in the detection of organic molecules. In this work, a low-cost, environment-friendly and suitable for large-scale production SERS substrate for rhodamine 6G (R6G), 4-aminothiophenol (4-ATP) and crystal violet (CV) detection has been fabricated by depositing copper (Cu) on the surface of mantis wings (MWs) by magnetron sputtering. In the process of preparation, we improved the enhancement effect of the substrate by controlling the sputtering time of Cu. Experiments showed that when the SERS substrate was prepared at the sputtering time of 30 min, the substrate exhibited excellent performance. The SERS performance of the fabricated flexible Cu/MW substrate when employed R6G as probe molecules shows an enhancement factor (EF) of 1.19 × 10 5 over 10 −3  M R6G solution. Besides, the prepared SERS substrate exhibits high sensitivity, strong stability and reproducibility. Sensitivity for relatively low R6G concentration (10 −6  M), 4-ATP concentration (10 −6  M) and CV (10 −6  M) were reported. [ABSTRACT FROM AUTHOR]

CoCrNi medium entropy alloy additive part was fabricated by laser directed energy deposition process. Based on an optimized additive manufacturing process parameters, the microstructure, tensile properties and corrosion performance in the XOY and XOZ planes were compared to learn the anisotropic properties of the additive part. The majority of the additive parts consisted of equiaxed grains, a small proportion consisted of elongated needle-like grains. The equiaxed and elongated needle-like grains in the XOY plane were finer compared to that in the XOZ plane. The corrosion electrochemical activity is uniform in the XOY plane, but varies at different heights in the XOZ plane base on scanning vibrating electrode technique results. Electron backscatter diffraction results near the fracture indicated a larger and relatively more homogeneous residual stress peak in the XOY plane. The tensile and yield strengths in the XOZ plane were lower than those in the XOY plane by approximately 98.5 MPa and 19.1 MPa. While the elongation in the XOZ plane was more than twice as high as that in the XOY plane. The reason for the anisotropic tensile behavior was the strong texture in the XOY plane and the relatively random grain orientation in the XOZ plane. Single crystal and polycrystalline molecular dynamics were used to simulate the anisotropic tensile properties in the XOZ and XOY planes. Single crystal simulation results showed that the maximum stress was 19.0 GPa and elongation was 13.0% when the stretching was along the [110] crystal orientation. The minimum stress was 17.1 GPa and elongation is 11.1% elongation when the stretching was along the [11 1 ‾ ] crystal orientation. Anisotropy existed for CrCoNi alloys in terms of tensile properties along different orientations. Polycrystalline simulation in the XOY plane results showed that the main cause of anisotropy between them was the tangling of the 1/6<112> dislocations and the 1/6<521> dislocations, which caused obstacles to dislocation motion and thus improved the strength of CoCrNi additive parts. High tensile strength in the XOY plane, not the XOZ plane, was attributed to 1/6<112> and 1/6<521> dislocation tangles at the (1 1 ‾ 0)/(115) planes. • The anisotropy of the XOY and XOZ planes is due to the fact that the XOY planes have stronger textures. • The corrosion electrochemical activity is uniform in the XOY plane, varies in the XOZ plane base on SVET results. • High tensile strength in the XOY plane was attributed to 1/6<112> and 1/6<521> dislocation tangles at the (1 1 ‾ 0)/(115) planes. [ABSTRACT FROM AUTHOR]

Accurately detecting human actions in video has many applications, such as video surveillance and somatosensory games. In this paper, we propose a spatial-aware attention module (SAM) and a temporal-aware attention module (TAM) for spatio-temporal action detection in videos. SAM first concatenates the feature maps of consecutive frames on the channel and then uses dilated convolutional layer followed by a sigmoid function to generate a spatial attention map. The resulting attention map contains spatial information from consecutive frames, so it helps the detector focus on salient spatial features to achieve more accurate localization of action instances in consecutive frames. TAM deploys several fully connected layers to generate a temporal attention map. The temporal attention map focuses on the temporal association of each spatial feature; it can capture the temporal association of action instances, thereby improving the detector to track actions. To evaluate the effectiveness of SAM and TAM, we build an efficient and strong anchor-free action detector, cascading spatio-temporal attention network, equipped with a 2D backbone and SAM and TAM modules. Extensive experiments on two benchmarks, JHMDB and UCF101-24, demonstrate the preferable performance of SAM and TAM. [ABSTRACT FROM AUTHOR]

This paper proposes power difference template as a new spatial-temporal representation for action recognition. Specifically, spatial power features are first extracted according to the transform of Gaussian convolution on gradients between logarithmic and exponential domain. Using the forward-backward frame power difference method, we thus present normalized projection histogram (NPH) to characterize segmented action spatial features by normalizing histogram of the 2D horizontal-vertical projections. Furthermore, from the perspective of energy conservation, motion kinetic velocity (MKV) is introduced as a supplement for representing temporal relationships of power features by supposing that the variation of power is produced by motion in the form of kinetic energy. Our power difference template fusing NPH and MKV is further integrated to a bag of word model for training and testing under a support vector machine framework. Experiments on KTH, UCF Sports, UCF101 and HMDB datasets demonstrate the effectiveness of the proposed algorithm. [ABSTRACT FROM AUTHOR]

In situ synthesized titanium boride (TiB) and titanium carbide (TiC)- reinforced Ti6Al4V composites were produced by directed energy deposition from a ball-milled mixture of Ti6Al4V and B 4 C powders. The effect of adding B 4 C on the microstructure, texture and mechanical properties was systematically investigated. The results showed that whisker TiB and equiaxed TiC were homogeneously distributed in the matrix. Also, the B 4 C/Ti composites are mainly composed of α-Ti, β-Ti, TiB, and TiC. The grain size of the as-deposited alloy decreased drastically from 550 to 120 μm due to the in situ-synthesized TiB and TiC. The formation of TiB and TiC promoted the precipitation of α-Ti with a non-Burgess orientation relationship, increasing the varieties of α variants and weakening the texture intensity of α-Ti. The tensile strength improved significantly because of the in situ-synthesized TiB and TiC. The ultimate tensile strength was 1126.1 MPa at room temperature, exhibiting a 15% maximum increase over the Ti6Al4V alloy, whereas the fracture elongation was reduced by 48.8%. Finally, the microstructure refinement mechanism was discussed in detail. [ABSTRACT FROM AUTHOR]

[Display omitted] • Crack-free CoCrNi laser directed energy deposition additive parts successfully obtained at high heat input. • High-angular grain boundary stress concentrations and excessive oxygen content in the additive parts were the main reasons for the crack formation. • Three crack suppression strategies could be proposed from this study, namely, reducing the heat input, performing additive experiments under argon-filled environment, and decreasing the oxygen content of the powder. Laser-directed energy deposition (l -DED) additive manufacturing of the CoCrNi medium entropy alloy is prone to cracking, especially with high laser heat input. Electron backscatter diffraction analysis showed crack formation and stress concentration at the high-angle grain boundaries. In addition, element content test results exhibited a higher oxygen content in the additive parts with high laser heat input. Electron probe X-ray microanalysis indicated that the oxygen was distributed uniformly in the additive parts. Corresponding molecular dynamics simulation results revealed that an increase in oxygen content led to a decrease in the tensile strength of the additive parts. Two methods of argon-filled environment l -DED experiments and low-oxygen CoCrNi feeding power (argon gas atomization) were used. Results showed that the number and size of cracks were significantly reduced in the additive parts obtained by a high heat input process when the l -DED was conducted in an argon-filled atmosphere and when powders with lower oxygen content were used. For the crack-free additive parts, the ultimate tensile strengths reached 625 MPa with high laser heat input. Three crack suppression strategies could be proposed from this study, namely, reducing the heat input, performing additive experiments under argon-filled environment, and decreasing the oxygen content of the powder. [ABSTRACT FROM AUTHOR]

A new methodology using a direct method for obtaining the best found trajectory planning and maximum dynamic load-carrying capacity (DLCC) is presented for a 5-degree of freedom (DOF) hybrid robot manipulator. A nonlinear constrained multiobjective optimization problem is formulated with four objective functions, namely, travel time, total energy involved in the motion, joint jerks, and joint acceleration. The vector of decision variables is defined by the sequence of the time-interval lengths associated with each two consecutive via-points on the desired trajectory of the 5-DOF robot generalized coordinates. Then this vector of decision variables is computed in order to minimize the cost function (which is the weighted sum of these four objective functions) subject to constraints on joint positions, velocities, acceleration, jerks, forces/torques, and payload mass. Two separate approaches are proposed to deal with the trajectory planning problem and the maximum DLCC calculation for the 5-DOF robot manipulator using an evolutionary optimization technique. The adopted evolutionary algorithm is the elitist nondominated sorting genetic algorithm (NSGA-II). A numerical application is performed for obtaining best found solutions of trajectory planning and maximum DLCC calculation for the 5-DOF hybrid robot manipulator. [ABSTRACT FROM AUTHOR]

Exploring action feature representation in consecutive video frames is a basic but critical issue in the area of computer vision. This paper presents a principled technique transforming gradient-based features into coherent spatial-temporal descriptors for action detection and recognition. Specifically, Gaussian convolution based technique is first applied to extract spatial features of each image frame on gradient layer, based on which the spatial features are further processed according to the forward-backward frame difference and correspondence fusion between frames for frame sequence representation. Furthermore, region of actions is labeled via thresholding the projection of difference features in horizontal-vertical direction while action types are classified via learning the fused features. We evaluate our approach on samples from KTH, Weizmann, UCF Sports dataset and ChangeDetection.NET dataset 2014, which demonstrates its applicability and effectiveness. [ABSTRACT FROM AUTHOR]

The band alignments at the interface of ZnO/HC(NH 2 ) 2 PbI 3 (FAPbI 3 ) heterojunction were measured by X-ray photoelectron spectroscopy. Core levels of Pb 5d and Zn 3d were utilized to align the valence-band offset (VBO). The VBO was determined to be 1.86 ± 0.30 eV, and the conduction-band offset (CBO) was concluded to be 0.05 ± 0.30 eV, manifesting that the ZnO/FAPbI 3 heterojunction has a type-I band alignment. The data of the band alignment of ZnO/FAPbI 3 heterojunction may benefit the design and development of novel perovskite solar cells (PSCs). [ABSTRACT FROM AUTHOR]

Chloride attack and carbonization are the main factors which affect the durability of concrete structures, and the respective theoretical models are systematically established. However, the quantitative analysis and models about the coupling effect of chloride attack and carbonization are less, so the precision and level of durability analysis of reinforced concrete are restricted. Diffusion-limited aggregation (DLA) model can finely simulate the process of gas diffusion and condensation with randomness and fractal characteristics, which is suitable for revealing the durability evolution process of the chloride attack, carbonization, and the coupling action in concrete. Based on the principle of DLA, considering the factors such as diffusion depth, concrete properties, and exposure conditions which influence the characteristics of chloride diffusion and carbonization, as well as the coupling effect, an integrated DLA model is established. The concentration of carbon dioxide and chloride at any time and any location can be obtained and dynamically displayed based on the DLA model. The performance predict method for concrete and steel bars considering fatigue effect is presented based on DLA, according to the demand for bridge durability analysis. Numerical examples show that the method can dynamically and intensively simulate the durability evolution process of reinforced concrete bridge. [ABSTRACT FROM AUTHOR]

Nickel and zinc salen complexes were simultaneously encapsulated in the supercages of the mesoporous zeolite A by using the flexible ligand method. This heterogeneous catalyst NiZnsalenA was characterized by X-ray diffraction, infrared spectroscopy, diffuse reflectance UV-vis spectroscopy, elemental analysis, and N adsorption/desorption experiments. The techniques of cyclic voltammetry (CV) and chronoamperometry (CA) were employed to investigate the electrochemical behavior and electrocatalytic activity toward the oxidation of methanol on NiZnsalenA glassy carbon electrode (GCE) in 0.1-M NaOH solution. The CV results presented a pair of redox peaks associated with the Ni(salen)(OH)/Ni(salen)O(OH) redox couple. NiZnsalenA also showed the superior electrocatalytic activity to the oxidation of methanol than pure Ni-modified electrode, mainly due to a synergetic effect in NiZnsalenA. This synergetic effect may originate from the interaction of Ni(salen) and Zn(salen) and/or the formation of dinuclear salen complexes via the lattice oxygen of the zeolitic host. The effects of the scan rate, methanol concentration, and OH concentration on methanol oxidation are investigated, and a possible mechanism is proposed that the oxidation of methanol is done by reaction with Ni(salen)O(OH) and also direct electrooxidation reaction. The kinetic parameters such as the electron transfer coefficient α and the rate constant k of the electrode reaction were estimated to be 0.39 and 1.59 s, respectively. In both the CA and CC studies, the process of methanol oxidation followed a Cottrellian behavior, and the diffusion coefficients D and D of methanol represented the similar tendency, where an initial sharp drop was terminated to a very slow change as the concentration of methanol was approaching 0.7 M. The catalytic rate constant k increased rapidly until the concentration of methanol was increased above 0.7 M, and then the values of k remained almost constant. [ABSTRACT FROM AUTHOR]

With the rapid development of cloud storage and cloud computing technology, users tend to store data in the cloud for more convenient services. In order to ensure the integrity of cloud data, scholars have proposed cloud data integrity verification schemes to protect users' data security. The storage environment of the Internet of Things, in terms of big data and medical big data, demonstrates a stronger demand for data integrity verification schemes, but at the same time, the comprehensive function of data integrity verification schemes is required to be higher. Existing data integrity verification schemes are mostly applied in the cloud storage environment but cannot successfully be applied to the environment of the Internet of Things in the context of big data storage and medical big data storage. To solve this problem when combined with the characteristics and requirements of Internet of Things data storage and medical data storage, we designed an SM2-based offline/online efficient data integrity verification scheme. The resulting scheme uses the SM4 block cryptography algorithm to protect the privacy of the data content and uses a dynamic hash table to realize the dynamic updating of data. Based on the SM2 signature algorithm, the scheme can also realize offline tag generation and batch audits, reducing the computational burden of users. In security proof and efficiency analysis, the scheme has proven to be safe and efficient and can be used in a variety of application scenarios. [ABSTRACT FROM AUTHOR]

[Display omitted] • Proposing a sponge loading method to enhance the magnetic separation effect; • Preparing a novel magnetic material with stereoscopic structure to adsorb Pb2+; • Studying the effect of MS loading on the physicochemical properties of MP; • Recognizing the role of MS, Fe 3 O 4 , and HAP in MPMS on its Pb2+ adsorption; • Four adsorption mechanisms of Pb(Ⅱ) to MPMS were quantitatively identified. Magnetic materials as adsorbents for wastewater treatment have attracted considerable attention because of the ease of separation of adsorbents for reuse. However, the efficient separation of magnetic materials, particularly nanoscale materials, remains challenging. Therefore, in this study, we developed an innovative method to enhance the separation performance of magnetic hydroxyapatite (MP) using melamine sponge (MS) loading. It was found that, although the magnetic moments of MP decreased from 15.54 emu/g to 11.51 emu/g after MS loading, MS-loaded MP (MPMS) exhibited better magnetic separation performance than MP. The analysis of adsorption isotherms suggests that the theoretical maximum adsorption capacity of Pb2+ at an initial pH of 4.85 using MPMS was 139.28 mg/g. Combined with adsorption kinetics and thermodynamics analysis, adsorption was categorized as a chemical, heterogeneous, and endothermic process. Moreover, in the adsorption mechanism, cation exchange, electrostatic interaction, dissolution/precipitation, and surface complexation mechanisms contributed 70.96%, 4.39%, 6.10%, and 18.55%, respectively, to the total Pb2+ removal under the experimental conditions. Hence, we provide a quick and low-cost solution for enhancing the downstream separation of magnetic adsorbents for reuse. [ABSTRACT FROM AUTHOR]

Nickel-plated carbon nanotubes (CNTs) as additive phases can greatly improve the friction and corrosion properties of composite materials. Nickel-coated CNTs/FeCoNbBSi amorphous composite coatings were prepared on the surface of a 45-steel shaft by using high-speed laser cladding technology. Results showed that the microstructure was refined after the amount of nickel-plated CNTs increased, but the crystallization remained sever, and the amorphous content decreased from 48.36% to 27.18%. The friction coefficient decreased, and the wear morphology improved with increasing amount of nickel-coated CNTs. The friction coefficient was only 0.22 when the amount of nickel-coated CNTs was 1 wt%. In addition, the bridging behavior of the nickel-coated CNTs at the crack increased corrosion time and improved the corrosion resistance of the coating. • The amorphous content decreased with the increase of CNTs content in the coating. • When the CNTs content reached 1 wt%, the surface work of the coating basically remained at 500 mv. • The more CNTs in the coating, the better self-lubrication performance and wear resistance. [ABSTRACT FROM AUTHOR]

Nickel and cobalt salen complexes were simultaneously encapsulated in mesoporous zeolite A by flexible ligand method. The prepared catalyst NiCosalenA was investigated for its electrochemical behavior and electrocatalytic activity towards the oxidation of methanol on glassy carbon electrode in 0.1 M NaOH solution. Upon encapsulation in zeolite A, the NiCosalen complex exhibits the typical cyclic voltammetric response, which can be anticipated for the Ni 2+ Co 2+ (Salen)(OH) 2 /Ni 3+ Co 3+ (Salen)O(OH) redox couple. It also showed much higher electrocatalytic activity towards the oxidation of methanol than pure NisalenA, due to a synergetic effect that may originate from the interaction of Ni(salen) and Co(salen) and/or the formation of dinuclear salen complexes in adjacent or appropriate sites in a nano-cage through the lattice oxygen of the zeolitic host. The mechanism of electrocatalytic oxidation of methanol on NiCosalenA modified electrode was proposed to be EC process. In both the chronoamperometric and chronocoulometric studies, the reaction of methanol electrooxidation followed a Cottrellian behavior and similar diffusion coefficients ( D ) of methanol were found to be 3.82 × 10 −7 cm 2 s −1 and 3.91 × 10 −7 cm 2 s −1 , respectively. The catalytic rate constant ( k cat ) was also calculated to be 5.52 × 10 5 cm 3 mol −1 s −1 in the range of 0.005–2.0 M of methanol. [ABSTRACT FROM AUTHOR]

Nickel and manganese salen complexes were simultaneously encapsulated in the supercages of the mesoporous zeolite A by using the flexible ligand method. The electrochemical behavior and electrocatalytic activity toward the electrooxidation of methanol on glassy carbon electrode coated with NiMnsalenA (NiMnsalenA/GCE) in 0.1 M NaOH solution were studied by cyclic voltammetry (CV), chronoamperometry (CA) and AC electrochemical impedance spectroscopy (EIS). The results showed that the addition of small amounts of Mn species can give rise to much higher electrocatalytic activity than the pure NisalenA toward the oxidation of methanol, mainly due to a synergetic effect that may originate from the interaction of Ni(salen) and Mn(salen) and/or the formation of dinuclear salen complexes via the lattice oxygen of the zeolitic host. Kinetic parameters such as the electron transfer coefficient α , the rate constant k s of the electrode reaction and the charge transfer coefficient of the catalytic reaction, α n were determined to be 0.40, 1.898 s −1 and 0.43, respectively, and the detection limit was found to be 97.66 μM. The mechanism of electrocatalytic oxidation of methanol on NiMnsalenA/GCE was investigated and proposed to be done by reaction with Ni 3+ (salen)O(OH) and also direct electro-oxidation reaction. The impedance behaviors showed different patterns at different applied potentials, indicating the changes of the rate-determining step, from the methanol electrooxidation leading to the formation of intermediates on the surface of electrode gradually to the oxidation and removal of adsorbed intermediates. The influence of methanol concentration on the impedance behaviors was also studied and the results demonstrated that the semidiameters of the Nyquist diagrams decreased with the increase of methanol concentration, signifying the acceleration of the reaction rate of methanol electrooxidation. [ABSTRACT FROM AUTHOR]

Jerk is the time rate of acceleration and mainly represents the nonstationary component in high frequency band of the earthquake wave. The study on jerk and its response spectra can enhance the recognition of the nonstationary ground motion. The mechanical meaning and research value of jerk are described. Jerk is recommended to be solved by establishing state-space equations and Runge-Kutta method. The solution method of elastic and inelastic jerk response spectra under ground motion is established, and the accurate jerk spectrum should be calculated directly according to numerical computing instead of pseudo-acceleration spectrum. The characteristics of jerk response spectra are studied according to the influencing factors, such as site condition, amplification factor, ductility factor, and reduction factor. The concept of impact reduction factor is presented. The statistical results show that the jerk spectrum has similar rules as the acceleration spectrum, and the amplitude is relative to the predominant period, especially for structures with short or medium period. If the ductility is improved, the effective jerk will reduce obviously, and the impact reduction factor will be enhanced. Different from the strength reduction factor, the impact reduction factor is nearly not relevant to the period. [ABSTRACT FROM AUTHOR]

In the present work, novel fly ash/phosphate geopolymer hollow sphere structures (FPGHSS) were prepared by the pre-bonding and curing technology. Moreover, the interface microstructure and its role on the compressive behavior were studied. The compressive properties of FPGHSS demonstrated a typical character of cellular materials, with three well defined stages in stress–strain curve. The compressive strength was approximately 5.8 MPa, and the failure of FPGHSS was mainly due to the evolution of the multi-collapsed layers of fly ashes and large macro-cracks during the compression. The microstructure of fly ash was composed of aluminosilicate glass phase, crystalline quartz and mullite. The phosphate geopolymer comprised of aluminum-phosphate phase and α -Al 2 O 3 , and the nano-pore structure was observed. Moreover, the chemical reaction interface of FPGHSS was generated. It should be noted that the horizontal cracks were mainly produced in fly ashes, and the evolution of horizontal cracks leaded to the clasped layers. Moreover, the large macro-cracks propagated preferentially in the phosphate geopolymer and along the interface region of FPGHSS, due to the dense glass phase of fly ash and the chemical reaction interface. Further, the interface structure between α -Al 2 O 3 and amorphous phase could increase the propagation path of cracks in phosphate geopolymer. [ABSTRACT FROM AUTHOR]

In the present work, the porous structure of fly ash/phosphate geopolymer hollow sphere structures (FPGHSS), prepared by pre-bonding and curing technology, has been characterized by multi-resolution methods from sub-millimeter to nano-scale. Micro-CT and confocal microscopy could provide the macroscopic distribution of porous structure on sub-millimeter scale, and hollow fly ashes with sphere shape and several sub-millimeter open cells with irregular shape were identified. SEM is more suitable to illustrate the distribution of micro-sized open and closed cells, and it was found that the open cells of FPGHSS were mainly formed in the interstitial porosity between fly ashes. Mercury porosimeter measurement showed that the micro-sized open cell of FPGHSS demonstrated a normal/bimodal distribution, and the peaks of pore size distribution were mainly around 100 and 10 μm. TEM observation revealed that the phosphate geopolymer was mainly composed of the porous area with nano-pores and dense areas, which were amorphous Al–O–P phase and α-Al 2 O 3 respectively. The pore size of nano-pores demonstrated a quasi-normal distribution from about 10 to 100 nm. Therefore, detailed information of the porous structure of FPGHSS could be revealed using multiple methods. [ABSTRACT FROM AUTHOR]

Amorphous coatings exhibit prominent properties, including high hardness and good wear resistance properties. In this study, Ni-based amorphous composite coatings with a composition of (Ni 0.6 Fe 0.4 ) 68 B 18 Si 10 Nb 4 were prepared on a mild steel substrate via high power diode laser cladding plus laser remelting processes. The microstructure of the coating was studied using X-ray diffraction (XRD) and a scanning electron microscope (SEM). The effect of the remelting scanning speed on the amorphous forming ability of the Ni-based alloy was studied systematically by experimental and numerical simulation methods. The results indicated that there was no amorphous phase formed when the scanning speed was 4 m/min and 5 m/min. The amorphous phase was observed when the remelting scanning speed was 6 m/min. The amorphous phase volume fraction increased with an increase in the remelting scanning speed. The fraction was found to be approximately 64% when the remelting speed was 8 m/min. The simulation results indicate that the increase in the remelting scanning speed may lead to lower residence time and higher cooling rate of the melted pool. As a result, high remelting scanning speed can be concluded to be a necessary condition for the formation of the amorphous phase when using the laser cladding plus laser remelting process. [ABSTRACT FROM AUTHOR]

Porous structure with micro-sized open cell was tailored for the sound absorption, and ceramic hollow sphere structures (CHSS) were prepared by low temperature pre-bonding and curing process. Micro-sized open cells of CHSS, which demonstrated normal/bimodal distribution, were mainly observed in the interstitial gaps of fly ashes. The CHSS with micro-sized open cells demonstrated a broadband sound absorption above 500 Hz, and its acoustics behavior was affected significantly by the porous structure. The calculated values of sound absorption based on the Pride–Allard model demonstrated similar trends as experimental results with the increase of frequency. [ABSTRACT FROM AUTHOR]

A novel white light-emitting diode based on a large Stokes shift (~200 nm) and using pure green light-emitting CdSeS quantum dots (QDs) with an Ag/ZnSnO/QDs/spiro-TPD/ITO structure has been fabricated in which ZnSnO and spiro-TPD are served as the electron and hole transport layer, respectively. The large Stokes shift of the CdSeS QDs excludes potentially Förster resonance energy transfer process, which allows spiro-TPD to act as both an emitter and hole transport layer. The devices exhibit a wide EL spectrum consisting of three components: blue emission from spiro-TPD, green emission from QD band-band recombination, and red emission from QD surface-state recombination. We further found that as the intensity ratios among these three components vary with bias the color of the QD light-emitting diodes is tunable. The device displays a good white light-emitting characteristic with CIE coordinates of (0.281, 0.384) at an appropriate bias. [ABSTRACT FROM AUTHOR]

Wireless network-on-chip (WiNoC) establishes a long-range single-hop wireless links on the base of the traditional planar metal interconnects network, which improve network performance in several aspects. The establishment of wireless link improves the diversity of path for packet transmitting, while simultaneously aggravates the deadlock problem, leading it to more complicated condemn. The traditional routing mechanism of wireless network on chip can avoid deadlock by sacrificing the adaptability of transmitting, which leads to unbalanced and insufficient use of limited on chip resources. In this paper, a fully adaptive routing mechanism is proposed to balance buffer utilization. At the same time, we proposed a hybrid virtual channel allocation strategy in order to make full use of buffer resources. For a large number of single-flit wired packets and wireless packets, more aggressive non-atomic allocation is adopted, and the remaining packets are arranged with atomic allocation to avoid potential deadlock. Experimental results showed that compared with the traditional deadlock solutions, the proposed scheme introduces less area and power consumption, and balances the utilization of buffer resources. Under the non-uniform Traffic Patterns, the proposed scheme has better performance in terms of delay and throughput, achieves 62.0% improvement compared to the traditional counterpart. [ABSTRACT FROM AUTHOR]

• When the scanning speed was 80.38 m/min, the volume fraction of amorphous phase was 74.48%. • When the scanning speed was 80.38 m/min, the crack of the coating section almost disappeared completely. • The residual tensile stress on the coating surface decreased with the increase of scanning speed. • Under the scanning speed of 80.38 m/min, the cooling rate of the coating could reach 1.08 × 105 °C/s. Fe-Co-B-Si-Nb amorphous coatings were deposited on 45 medium carbon steel under different scanning speeds by high-speed laser cladding technology. The results showed that the surface roughness of the coating became lower and the surface of the coating became smoother with the increase in scanning speed. In addition, the residual tensile stress and the thermal expansion coefficient decreased with the increase in the scanning speed. When the scanning speed was 80.38 m/min, the residual tensile stress was 106.13 ± 24.03 MPa. The residual stress was reduced by more than 50% compared with the scanning speed of 37.68 m/min. The XRD and TEM observation results of the coating at the scanning speed of 80.38 m/min showed a large volume fraction of amorphous phase and some crystalline dendrites. Under the scanning speed of 80.38 m/min, the cooling rate at the top of the coating could reach 1.08 × 105 °C/s, which greatly increased the amorphous formation ability. The hardness and wear resistance properties of the coating were also tested and analyzed. Better performance of the coatings was obtained when the scanning speed was higher. [ABSTRACT FROM AUTHOR]