125 results on '"Wei T"'
Search Results
2. Multiobjective Optimization Strategy for Enhancing the Efficiency and Quality of Organic Thin-Film Manufacturing with Electrohydrodynamic Atomization Coating
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Chao Hu, Jiankui Chen, Wei Chen, Wei Tang, Guozhen Wang, Fei Pan, and Zhouping Yin
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Chemistry ,QD1-999 - Published
- 2024
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3. Calculation of Porosity and CO2 Content in CO2‑Bearing Gas Formations Based on Density and Neutron Logging Forward and Inverse Methods
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Hengrong Zhang, Wei Tan, Desheng Hu, Xiangyang Hu, Jianmeng Sun, and Dong Yang
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Chemistry ,QD1-999 - Published
- 2024
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4. Theoretical studies of two-dimensional structure design and topological electronic properties of organic Dirac materials
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Aizhu Wang, Wei Tan, Hongbo Zhao, Hongguang Wang, Na Ren, Longhua Ding, Xin Yu, and Jingyang Peng
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Two-dimensional Dirac models ,Organic Dirac materials ,Covalent-organic frameworks ,Metal-organic frameworks ,Topological electronic properties ,Chemistry ,QD1-999 ,Physics ,QC1-999 - Abstract
Owing to the significant development in graphene, an increasing number of studies have been conducted to identify novel two-dimensional (2D) organic materials with Dirac cones and topological properties. Although a series of toy models based on specific lattice patterns has been proposed and demonstrated to possess a Dirac cone, realistic materials corresponding to the lattice models must be identified to achieve excellent properties for practical applications. To understand factors contributing to the rarity of 2D organic Dirac materials and provide guidance for identifying novel organic Dirac systems, we review recent theoretical studies pertaining to various 2D Dirac models and their corresponding organic Dirac materials, including the Haldane, Kagome, Libe, line-centered honeycomb, and Cairo pentagonal models. Subsequently, the corresponding structural and topological electronic properties are summarized. Additionally, we investigate the relationship between the existence of Dirac cones and their structural features, as well as the manner by which Dirac points emerge and propagate in these systems.
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- 2024
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5. Water Injection Into Coal Seams for Outburst Prevention: The Coupling Effect of Gas Displacement and Desorption Inhibition
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Wei Tian, Wei Yang, Liming Luo, Guangyao Si, Zhaoyang Zhang, and Zhichao Zhang
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Chemistry ,QD1-999 - Published
- 2024
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6. Protocol for three-dimensional shaping strategy via solidifying polygonal nanofluid drops
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Haoting Cai, Wei Tong, Lichuan Wei, Yupeng Jiang, Yugang Zhao, Hua Zhang, Chun Yang, and Ping Cheng
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Energy ,Chemistry ,Material sciences ,Environmental sciences ,Science (General) ,Q1-390 - Abstract
Summary: Mesoscale to nanoscale three-dimensional (3D) fabrication mostly requires complicated industry processing techniques. Here, we present a protocol for 3D shaping control by solidifying a water-based TiO2 nanofluid drop on a polygonal wettability-patterned surface. We detail the steps for preparing stable TiO2 nanofluid and wettability-patterned surfaces. We then describe the experimental procedure to obtain various and precise 3D morphologies by adjusting the deposited TiO2 nanofluid drop volume. This protocol provides a promising technique for future 3D manufacturing.For complete details on the use and execution of this protocol, please refer to Jiang et al.1 : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.
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- 2024
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7. High-Sensitivity Flexible Capacitive Pressure Sensors Based on Biomimetic Hibiscus Flower Microstructures
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Ronghua Lan, Jinyong Zhang, Jing Chen, Wei Tang, Qingyang Wu, Xiaolin Zhou, Xiaoyang Kang, Jue Wang, Hongbo Wang, and Hui Li
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Chemistry ,QD1-999 - Published
- 2024
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8. A Small Molecule Chemiluminophore with near 600 nm Emission for In Vivo Imaging of Myeloperoxidase and Inflammatory Diseases
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Tianjiao Meng, Xueru Zhang, Wei Tang, Chenghui Liu, and Xinrui Duan
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Medical technology ,R855-855.5 ,Chemistry ,QD1-999 - Published
- 2024
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9. Using inexpensive jell-o chips for hands-on microfluidics education
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Yang, Cheng Wei T., Ouellet, Eric, and Lagally, Eric T.
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Microfluidics -- Study and teaching ,Cookery (Gelatin) -- Usage ,Chemistry, Analytic -- Study and teaching ,Chemistry - Abstract
As the field of microfluidics continues to grow, there is an increasing demand for public education about this technology. This article presents a quick, simple, safe, and inexpensive method for teaching microfiuidics to younger students and the general public. (To listen to a podcast about this article, please go to the Analytical Chemistry multimedia page at pubs.acs.org/page/anchem/audio/ index.html.) 10.1021/ac902926x
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- 2010
10. Comparison of Diffuse Reflectance and Diffuse Transmittance Vis/NIR Spectroscopy for Assessing Soluble Solids Content in Kiwifruit Coupled with Chemometrics
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Yu Xia, Wei Zhang, Tianci Che, Jinghao Hu, Shangqiao Cao, Wenbo Liu, Jie Kang, Wei Tang, and Hongbo Li
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kiwifruit ,diffuse reflectance ,diffuse transmittance ,soluble solids content ,partial least squares regression ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Kiwifruit, as a climacteric fruit, undergoes rapid ripening and senescence after harvest, making it highly susceptible to softening, rotting, and spoilage. Therefore, monitoring the key quality parameters of kiwifruit, particularly the accurate detection of soluble solids content (SSC), is considered crucial. The performance of two spectral acquisition methods—diffuse reflectance and diffuse transmission—in detecting SSC in kiwifruit was compared. Various preprocessing methods and feature wavelength selection techniques were employed, and regression models were constructed using partial least squares (PLS) analysis. The stability and accuracy of the models were validated through an independent validation set. The results indicated that the spectral data acquired by the diffuse reflectance method, preprocessed using Savitzky–Golay smoothing and combined with competitive adaptive reweighted sampling (CARS), yielded a coefficient of determination (R2) of 0.98 for the prediction set, with a root-mean-square error (RMSE) of 0.66. In contrast, the spectral data obtained by the diffuse transmission method, preprocessed using multiplicative scatter correction and combined with CARS, achieved an R2 of 0.95 and an RMSE of 0.93 for the prediction set. This study demonstrated that both methods were effective for detecting SSC in kiwifruit, with the diffuse reflectance method showing the greater advantage.
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- 2024
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11. Element Migration of Mineralization-Alteration Zones and Its Geological Implication in the Beiya Porphyry–Skarn Deposit, Northwestern Yunnan, China
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Fei Liu, Runsheng Han, Yuxinyue Guo, Mingzhi Wang, and Wei Tan
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element migration ,mineralization-alteration zone ,porphyry copper system ,Beiya porphyry–skarn deposit ,Sanjiang metallogenic belt ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Porphyry and the associated skarn-type deposit is one of the most important types of ore deposits worldwide, which usually exhibit significant zoning of mineralization-alteration, but the research on element migration in these mineralization-alteration zones is relatively weak. The Beiya porphyry–skarn gold-polymetallic deposit is a super-large Cenozoic deposit located in the Sanjiang metallogenic belt, northwestern Yunnan, China. In this paper, through a detailed analysis of mineralization and alteration zoning and its element migration regularity, the findings are as follows: (1) Three types of hydrothermal alteration—porphyry alteration, contact alteration, and wall-rock alteration—are developed, and porphyry alteration includes potassic, phyllic, propylitic, and argillic alteration; (2) five types of mineralization—porphyry-type Cu–Au–(Mo), skarn-type Au–Fe–(Cu), hydrothermal vein-type Au–Fe, distal hydrothermal-type Pb-polymetallic, and oxidizing-leaching enriched-type Au—occur in a diversity of forms, which are dominantly controlled by structures and lithologies; (3) concentric-banded mineralization-alteration zones are exhibited centrally from the alkaline porphyry outward or upward, namely [porphyry alteration] potassic → phyllic → propylitic → argillic → [contact alteration] skarnitization–marbleization → [wall-rock alteration] marbleization–silicification–calcitization; (4) porphyry-type mineralization predominantly forms within potassic and phyllic zones, while skarn-type mineralization occurs in contact alteration zones, and proximal and distal hydrothermal (vein)-type mineralization are commonly distributed in marbleization–silicification–calcitization alteration zones; and (5) element migration analysis demonstrates a significantly lateral and vertical zoning in the metallogenic element association of Cu–Mo → Cu–Au → Au–Fe–Cu → Au–Fe → Pb–Zn–Au–Ag–Fe from alkaline porphyry outward to the wall-rock. The mineralization-alteration zoning model indicates the Beiya deposit has similar mineralization and alteration zone characteristics to the typical porphyry copper system; and element migration within mineralization-alteration zones provides new scientific information for understanding the metallogenic regularity and prospecting at Beiya, as well as the similar types of deposits in the Sanjiang metallogenic belt and elsewhere in the world.
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- 2024
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12. Computational Analysis Suggests That AsnGTT 3′-tRNA-Derived Fragments Are Potential Biomarkers in Papillary Thyroid Carcinoma
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Annie N. Do, Shruti Magesh, Matthew Uzelac, Tianyi Chen, Wei Tse Li, Michael Bouvet, Kevin T. Brumund, Jessica Wang-Rodriguez, and Weg M. Ongkeko
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tRNA-derived fragment ,tRF ,non-coding RNA ,biomarker ,THCA ,PTC ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Transfer-RNA-derived fragments (tRFs) are a novel class of small non-coding RNAs that have been implicated in oncogenesis. tRFs may act as post-transcriptional regulators by recruiting AGO proteins and binding to highly complementary regions of mRNA at seed regions, resulting in the knockdown of the transcript. Therefore, tRFs may be critical to tumorigenesis and warrant investigation as potential biomarkers. Meanwhile, the incidence of papillary thyroid carcinoma (PTC) has increased in recent decades and current diagnostic technology stands to benefit from new detection methods. Although small non-coding RNAs have been studied for their role in oncogenesis, there is currently no standard for their use as PTC biomarkers, and tRFs are especially underexplored. Accordingly, we aim to identify dysregulated tRFs in PTC that may serve as biomarker candidates. We identified dysregulated tRFs and driver genes between PTC primary tumor samples (n = 511) and adjacent normal tissue samples (n = 59). Expression data were obtained from MINTbase v2.0 and The Cancer Genome Atlas. Dysregulated tRFs and genes were analyzed in tandem to find pairs with anticorrelated expression. Significantly anticorrelated tRF-gene pairs were then tested for potential binding affinity using RNA22—if a heteroduplex can form via complementary binding, this would support the hypothesized RNA silencing mechanism. Four tRFs were significantly dysregulated in PTC tissue (p < 0.05), with only AsnGTT 3′-tRF being upregulated. Binding affinity analysis revealed that tRF-30-RY73W0K5KKOV (AsnGTT 3′-tRF) exhibits sufficient complementarity to potentially bind to and regulate transcripts of SLC26A4, SLC5A8, DIO2, and TPO, which were all found to be downregulated in PTC tissue. In the present study, we identified dysregulated tRFs in PTC and found that AsnGTT 3′-tRF is a potential post-transcriptional regulator and biomarker.
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- 2024
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13. Synthesis of phosphino oxazoline ligand libraries from amino acid and phosphino carboxylate building blocks
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Gilbertson, Scott R. and Chang, Cheng-Wei T.
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Coordination compounds -- Research ,Ligands -- Research ,Biological sciences ,Chemistry - Abstract
A modular route in generating ligands made from phosphine-containing acids and various amino acids employs an alkyl chain as a bridging structure connecting chelating functionalities. This allows the addition of a second chiral center next to the phosphine substituent. The resulting product is a diastereomeric ligand containing two chiral centers which can act either in concert or dissonance.
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- 1998
14. Optimization of Formula for Chromium-Free Zinc–Aluminum Coatings Based on Extension Analytic Hierarchy Process
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Fu Zhu, Yu Xin, Wei Tian, Yan Tang, Lin Hou, and Yuhang Gao
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chromium-free zinc–aluminum coating ,extension theory ,analytic hierarchy process ,scoring of evaluation indicators ,comprehensive analysis method ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The service performance of chromium-free zinc–aluminum coatings exhibits characteristics from multiple perspectives. Fully considering the physical properties, corrosion resistance, and economic viability of the coatings, this study incorporates the concepts of “domain” and “degree” from extenics theory into the analytic hierarchy process to optimize the formulation of chromium-free zinc–aluminum coatings. The findings reveal that the extension analytic hierarchy process takes into account the diversity of evaluation indicators, enhancing the objectivity and accuracy of the comprehensive evaluation results. Nine formulations were developed using a four-factor, three-level orthogonal experiment to evaluate the effects of metal powder, PEG-400, KH-560, and sodium molybdate on the service performance of chromium-free zinc–aluminum coatings. Utilizing an extensible hierarchical sorting weight system alongside a performance index grading and scoring method, 3# emerged with the highest score, indicating the best overall performance. The research outcomes offer innovative insights and technical support for optimizing the formulations of chromium-free zinc–aluminum coatings and other coatings.
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- 2024
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15. Redirecting extracellular proteases to molecularly guide radiosensitizing drugs to tumors
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J. Silvio Gutkind, Maria F. Camargo, Larry A. Gross, Matthew K. Doan, Joseph A. Aguilera, Wei T. Li, Maryam A. Quraishi, Ezra E.W. Cohen, Sunil J. Advani, Mara Gilardi, Weg M. Ongkeko, Stephen R. Adams, Jessica L. Crisp, Tao Jiang, and Dina V. Hingorani
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Radiation-Sensitizing Agents ,Proteases ,Radiosensitizer ,Cell ,Biomedical Engineering ,Biophysics ,Bioengineering ,Cell-Penetrating Peptides ,02 engineering and technology ,Article ,Cell Line ,Biomaterials ,Antibody drug conjugates ,03 medical and health sciences ,Drug Delivery Systems ,Rare Diseases ,Cell surface receptor ,Cell Line, Tumor ,medicine ,Humans ,Radiosensitization ,Cancer ,030304 developmental biology ,Targeted drug delivery ,0303 health sciences ,Tumor ,Cell penetrating peptides ,Radiotherapy ,Chemistry ,021001 nanoscience & nanotechnology ,Orphan Drug ,Good Health and Well Being ,medicine.anatomical_structure ,5.1 Pharmaceuticals ,Mechanics of Materials ,Tumor progression ,Drug delivery ,Ceramics and Composites ,Cancer research ,Cell-penetrating peptide ,Development of treatments and therapeutic interventions ,0210 nano-technology ,Peptide Hydrolases ,Biotechnology - Abstract
Patients with advanced cancers are treated with combined radiotherapy and chemotherapy, however curability is poor and treatment side effects severe. Drugs sensitizing tumors to radiotherapy have been developed to improve cell kill, but tumor specificity remains challenging. To achieve tumor selectivity of small molecule radiosensitizers, we tested as a strategy active tumor targeting using peptide-based drug conjugates. We attached an inhibitor of the DNA damage response to antibody or cell penetrating peptides. Antibody drug conjugates honed in on tumor overexpressed cell surface receptors with high specificity but lacked efficacy when conjugated to the DNA damage checkpoint kinase inhibitor AZD7762. As an alternative approach, we synthesized activatable cell penetrating peptide scaffolds that accumulated within tumors based on matrix metalloproteinase cleavage. While matrix metalloproteinases are integral to tumor progression, they have proven therapeutically elusive. We harnessed these pro-tumorigenic extracellular proteases to spatially guide radiosensitizer drug delivery using cleavable activatable cell penetrating peptides. Here, we tested the potential of these two drug delivery platforms targeting distinct tumor compartments in combination with radiotherapy and demonstrate the advantages of protease triggered cell penetrating peptide scaffolds over antibody drug conjugates to deliver small molecule amine radiosensitizers.
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- 2020
16. Production of 14α-Hydroxy Progesterone Using a Steroidal Hydroxylase from Cochliobolus lunatus Expressed in Escherichia coli
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Yaowen Chang, Han Liu, Wei Tian, and Zunxue Chang
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steroid 14α-hydroxylation ,14α-OH progesterone ,cytochrome P450 ,Cochliobolus lunatus ,Escherichia coli ,Chemical technology ,TP1-1185 ,Chemistry ,QD1-999 - Abstract
Steroids with hydroxylation at C14 are drawing increased attention because of their diverse biological activities and applications. P-450lun from Cochliobolus lunatus is the first fungal cytochrome P450 reported to have 14α-hydroxylase activity. Studies have shown that P-450lun catalyzes the hydroxylation of progesterone (PROG) at C14α with low regiospecificity and activity. To improve its regiospecificity and activity for PROG, truncated forms of P-450lun and its cognate redox partner CPRlun were functionally co-expressed in Escherichia coli. Then, a semi-rational protein engineering approach was applied to P-450lun, resulting in a double-site mutant E109A/F297W with enhanced 14α-position selectivity for PROG compared with the wild-type P-450lun (97% vs. 28%). Protein structure analysis revealed that the F297W substitution can hinder the binding pose for 11β-hydroxylation product formation. Finally, whole-cell catalysis was optimized, and the final titer of 14α-OH-PROG reached 16.0 mg/L. This is the first report where a fungal 14α-hydroxylase was functionally expressed in Escherichia coli. The steroid hydroxylation system obtained in this study can serve as a basis for the synthesis of 14α-hydroxylated PROG and the rapid evolution of eukaryotic cytochrome P-450lun.
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- 2024
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17. Discovery of novel small-molecule aldehyde dehydrogenase 2 activators based on drug repurposing
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Wei Tian, Xiangpei Sun, Xing Gao, Wentao Wang, Zhuo Chen, Xin Chen, and Canhui Zheng
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Aldehyde dehydrogenase-2 ,Activator ,Virtual screening ,Docking ,Pharmacophore ,Drug repurposing ,Chemistry ,QD1-999 - Abstract
Aldehyde dehydrogenase 2 (ALDH2) plays an important role in the detoxification of reactive aldehydes under oxidative stress. Because an estimated 50% of East Asians carry a common ALDH2 deficient variant with decreased enzyme activity and are more susceptible to toxic aldehydes, more recent findings have highlighted the therapeutic potential of ALDH2 activators in aldehyde-related diseases such as cardiovascular injury. Drug repurposing has unique advantages in providing new lead compounds with good drug-like properties. Herein, we identified Tadalafil from DrugBank as a novel ALDH2 activator using a combination strategy of docking-based and pharmacophore-based virtual screening based on exploring the activation mechanism. Then a hit-based substructure search was completed and has led to the discovery of 5 hits, among which A1 showed better ALDH2 activation activity than Tadalafil. This study provides a good basis for the further research of ALDH2 activators.
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- 2023
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18. Effect of polarization, phase and amplitude on depletion focus spot in STED
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Tang Y.-G., Zhang Y.-H., and Wei T.-D.
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Super-resolution microscopy ,Chemistry ,business.industry ,STED microscopy ,Polarization (waves) ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials ,Full width at half maximum ,Amplitude ,Optics ,Microscopy ,Stimulated emission ,business ,Excitation - Abstract
As Stimulated Emission Depletion (STED) super-resolution microscopy has a lower resolution, this paper explores the effects of multiphysical variables including light polarization, phases and amplitudes on the focal spots, in order to form a ring-shape depletion focus spot with sharper Full Width at Half Maximum (FWHM) and to increase the resolution of the microscopy. According to Richards-Wolf vector theory, the models of depletion focus spots were established under the actions of polarization, phase and amplitude, the focus spot distribution was calculated in different polarization, phase and amplitude conditions and the distribution of effective fluorescent excitation was obtained by optimizing the parameters. The results show that: by using azimuthal polarization light as depletion, the FWHM is better than those of radial or circular ones; modulations of phase and amplitude are able to reduce the FWHM, and the theoretical value of effective fluorescent excitation FWHM is only 13.2 nm after optimization. By using polarization state, phase and amplitude to modulate the depletion focus spot, the FWHM can be reduced and a higher resolution can be obtained, which is more effective than that using only single physical variable. Moreover, the high quality depletion focus spot and super-resolution ability can be obtained with azimuthal polarization light in STED and the resolution can further be optimized by phase or amplitude modulations based on different realities.
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- 2014
19. Synthesis of new disugar phosphine ligands and their use in asymmetric hydrogenation
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Gilbertson, Scott R. and Chang, Cheng-Wei T.
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Organic compounds -- Synthesis ,Ligands -- Research ,Hydrogenation -- Observations ,Biological sciences ,Chemistry - Abstract
The disugar diphosphine ligands, benzyl- and methyl-protected diphosphines (9 and 10) are prepared and are then used in the asymmetric hydrogenation of alpha-(N-acetylamino)acrylate leading to products in high enantiomeric excess. The disugar D-trehalose is used as the starting material which is subsequently protected to yield 9 and 10.
- Published
- 1995
20. Regular pattern of the single-atom M-N3/C (M = Sc ∼ Cu) toward the activation of O2
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Jin-Tao Gou, Ting-Hao Liu, Shuai Fu, Yin-Sheng Zhang, Wei Tai, Chang-Wei Hu, and Hua-Qing Yang
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GGA-PBE/DNP ,Activation of O2 ,N-doped graphene ,First-row transition metal ,Chemistry ,QD1-999 - Abstract
The single-atom metal M-N-C catalyst displays a certain activity for the aerobic oxidation. A single-atom M-N3/C (M = Sc ∼ Cu) surface was modeled as a M-N-C catalyst, in which a metal adatom was located on a monovacancy defective nitrogen-doped graphene. Over M-N3/C (M = Sc ∼ Cu), the activation mechanism has been theoretically studied at the GGA-PBE/DNP level. The stability of M-N3/C increases as Cu < Mn < Fe = Ni < Cr < Co < Sc < V < Ti. Here, Ti-N3/C is the most favorable among the first-row transition metal (Sc ∼ Cu), whereas Co-N3/C is the most stable among the late first-row transition metal Mn ∼ Cu. For M-N3/C (M = Sc ∼ Cu), both the adsorption strength of O2 and the activity of O2 dissociation decrease sequentially with the increase of atomic number, i.e., Sc > Ti > V > Cr > Mn > Fe > Co > Ni > Cu, which have a negative correlation with either charge or the energy level difference (ɛd) for the center of the d-bands relative to the Fermi level of metal-site. Thermodynamically, the possibility for the dissociation of O2 decreases as Mn > Ti > Cu > Ni > Cr > V = Fe > Co > Sc.
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- 2023
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21. The enhancement effect of Nb over CeSi2 catalyst for the low-temperature NH3-SCR performance
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Lipeng Ding, Shaoxiong Zhang, Qinglong Liu, Peng Yang, Yandi Cai, Wei Tan, Wang Song, Fei Gao, and Lin Dong
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Low-temperature NH3-SCR activity ,Ce-Si mixed oxide ,Niobium-modifying ,Enhanced surface acidity ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Tuning the acid site on the surface of the catalyst tends towards facilitating the selective reduction of NOx by NH3 (NH3-SCR). In this study, a set of catalysts for the Nb/CeSi2 with different loadings of niobium were synthesized and evaluated in terms of NH3-SCR over a broad temperature range. The results indicated that a catalyst for 20Nb/CeSi2 exhibited the best low-temperature NH3-SCR performance while maintaining excellent SO2/H2O resistance. These catalysts were also characterized by BET, XRD, Raman, NH3-TPD, and H2-TPR to further explore the correlations between catalyst structure and performance after adding niobium. For the Nb/CeSi2 catalysts, the surface structure was blocked by niobium species, resulting in varying degrees of reduction in the specific surface areas. Also, the total acidity decreased with the declines of the specific surface areas while the acidity per unit was enhanced, which facilitates the occurrence of the SCR reaction. Furthermore, in situ DRIFTS results indicated that SCR reaction could occur following the Eley-Rideal (E-R) mechanism and Langmuir-Hinshelwood (L-H) mechanism simultaneously over 20Nb/CeSi2 catalyst, which could be attributed to the interaction between niobium and ceria in favor of the activation of inert surface nitrate, considered the primary factor for the improvement of the catalyst performance at low-temperature.
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- 2023
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22. Development of Compact and Robust Physical System for Strontium Optical Lattice Clock
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Yingxin Chen, Chihua Zhou, Wei Tan, Feng Guo, Guodong Zhao, Jian Xia, Junwei Meng, and Hong Chang
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physical system ,compact and robust ,optical clock ,strontium atoms ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Compact and robust optical clocks are significant in scientific research and engineering. Here, we present a physical system for a strontium atomic optical clock with dimensions of 465 mm × 588 mm × 415 mm and a weight of 66.6 kg. To date, this is one of the most compact physical systems ever reported. The application of the magnetic shielding box in this physical system allowed the effect of external magnetic field fluctuation on cold atoms to be negligible. The physical system passed rigorous environmental tests and remained operational. A wavelength meter integrated in this physical system could monitor the wavelengths of the incident laser, and it could automatically calibrate the wavelengths of all lasers using a microcomputer. This compact and robust physical system could be a hardware basis for demonstrating a portable optical clock or even a space optical clock.
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- 2024
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23. Catalytic Partial Oxidation of Methane to Methanol over Fe2O3/MWCNTs
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Zhengqing Zhou, Yinghua Zhang, Zhian Huang, Jia Liu, Jinguo Sang, Zuochun Luan, Wei Tian, Yukun Gao, Xingyu Zhang, Yucheng Ji, and Tao Tang
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partial oxidation ,carbon nanotubes ,weak acid ,non-noble metal ,Chemical technology ,TP1-1185 ,Chemistry ,QD1-999 - Abstract
The catalytic partial oxidation of methane (CPOM) to methanol has been regarded as a promising approach for methane utilization, despite that the conversion remains a formidable challenge in the perspective of catalysts. A novel catalyst system of multi-wall carbon nanotubes (MWCNTs) that supported Fe2O3 with existing I2, consisting of non-noble metal and working in weak acid at an ambient temperature, was investigated for CPOM. MWCNTs supported the Fe2O3 catalyst, which was prepared by the impregnation method and characterized via HRTEM, XRD, XPS, FT-IR, and BET techniques. The characterization results reveal that, as a non-noble metal catalyst, the Fe2O3/MWCNTs catalyst had a good catalytic performance and stability in the CPOM. With the variation of reaction pressure and the dosage of Fe2O3/MWCNTs, the catalyst system obtained the highest methane conversion rate of 7.41% and methanol selectivity of 86.3%, which is analogous to that of the equivalently strong acid catalyst system. The I2-Fe2O3/MWCNTs catalyst system has great potential in the application of CPOM under mild, environmentally benign conditions, such as non-noble metal requirement, ambient temperature, and weak acid. The reaction mechanism was discussed.
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- 2024
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24. Amphisbaena: A Novel Persistent Buffer Management Strategy to Improve SMR Disk Performance
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Chi Zhang, Fangxing Yu, Shiqiang Nie, Wei Tang, Fei Liu, Song Liu, and Weiguo Wu
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shingled magnetic recording ,RMW ,in-place update ,garbage collection ,persistent buffer ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The explosive growth of massive data makes shingled magnetic recording (SMR) disks a promising candidate for balancing capacity and cost. SMR disks are typically configured with a persistent buffer to reduce the read–modify–write (RMW) overhead introduced by non-sequential writes. Traditional SMR zones-based persistent buffers are subject to sequential-write constraints, and frequent cleanups cause disk performance degradation. Conventional magnetic recording (CMR) zones with in-place update capabilities enable less frequent cleanups and are gradually being used to construct persistent buffers in certain SMR disks. However, existing CMR zones-based persistent buffer designs fail to accurately capture hot blocks with long update periods and are limited by an inflexible data layout, resulting in inefficient cleanups. To address the above issues, we propose a strategy called Amphisbaena. First, a two-phase data block classification method is proposed to capture frequently updated blocks. Then, a locality-aware buffer space management scheme is developed to dynamically manage blocks with different update frequencies. Finally, a latency-sensitive garbage collection policy based on the above is designed to mitigate the impact of cleanup on user requests. Experimental results show that Amphisbaena reduces latency by an average of 29.9% and the number of RMWs by an average of 37% compared to current state-of-the-art strategies.
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- 2024
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25. Interactions between fibroin and sericin proteins from Antheraea pernyi and Bombyx mori silk fibers
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Jin Zhang, George W. Greene, Quan X. Li, Hai J. Zhu, Xun G. Wang, Jing L. Li, Wei T. Zhou, and Shan Du
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Wild silk ,Surface Properties ,Silk ,Fibroin ,02 engineering and technology ,Antheraea pernyi ,Moths ,010402 general chemistry ,01 natural sciences ,Sericin ,Biomaterials ,Colloid and Surface Chemistry ,Bombyx mori ,Animals ,Particle Size ,Sericins ,Bombyx ,biology ,Chemistry ,Adhesion ,021001 nanoscience & nanotechnology ,biology.organism_classification ,0104 chemical sciences ,Surfaces, Coatings and Films ,Electronic, Optical and Magnetic Materials ,SILK ,Biophysics ,0210 nano-technology ,Fibroins ,Protein Binding - Abstract
Silkworm silk fibers are core-shell composites of fibroin and sericin proteins. Studying the interactions between fibroin and sericin is essential for understanding the properties of these composites. It is observed that compared to the domestic silk cocoon Bombyx mori (B. mori), the adhesion between fibroin and sericin from the wild silk cocoon, Antheraea pernyi (A. pernyi), is significantly stronger with a higher degree of heterogeneity. The adsorption of A. pernyi sericin on its fibroin is almost twice the value for B. mori sericin on fibroin, both showing a monolayer Langmuir adsorption. (1)H NMR and FTIR studies demonstrate on a molecular level the stronger interactions and the more intensive complex formation between A. pernyi fibroin and sericin, facilitated by the hydrogen bonding between glycine and serine. The findings of this study may help the design of composites with superior interfacial adhesion between different components.
- Published
- 2016
26. Sonication-assisted oligomannoside synthesis
- Author
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Tanifum, Christabel T. and Cheng-Wei T. Chang
- Subjects
Glycosylation -- Analysis ,Oligosaccharides -- Chemical properties ,Solvation -- Analysis ,Biological sciences ,Chemistry - Abstract
The characterization of newly developed sonication-mediated glycosylation protocol for the synthesis of oligomannosides is described. The protocol could also be applied to the glycosyl donors that are known to have low reactivity.
- Published
- 2009
27. Degeneration of flow pattern in acousto-elastic flow through sharp-edge microchannels
- Author
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Yuwen Lu, Wei Tan, Zhifang Liu, Shuoshuo Mu, and Guorui Zhu
- Subjects
Microfluidics ,Acoustofluidics ,Acoustic streaming ,Viscoelastic fluid ,Elasticity ,Chemistry ,QD1-999 ,Acoustics. Sound ,QC221-246 - Abstract
Acoustic streaming (AS) is the steady time-averaged flow generated by acoustic field, which has been widely used in enhancing mixing and particle manipulation. Current researches on acoustic streaming mainly focus on Newtonian fluids, while many biological and chemical solutions exhibit non-Newtonian properties. The acoustic streaming in viscoelastic fluids has been studied experimentally for the first time in this paper. We found that the addition of polyethylene oxide (PEO) polymer to the Newtonian fluid significantly altered the flow characteristics in the microchannel. The resulting acousto-elastic flow showed two modes: positive mode and negative mode. Specifically, the viscoelastic fluids under acousto-elastic flow exhibit mixing hysteresis features at low flow rates, and degeneration of flow pattern at high flow rates. Through quantitative analysis, the degeneration of flow pattern is further summarized as time fluctuation and spatial disturbance range reduction. The positive mode in acousto-elastic flow can be used for the mixing enhancement of viscoelastic fluids in the micromixer, while the negative mode provides a potential method for particle/cell manipulation in viscoelastic body fluids such as saliva by suppressing unstable flow.
- Published
- 2023
- Full Text
- View/download PDF
28. Peptide-based siRNA delivery system for tumor vascular normalization and gene silencing in 4T1 cells
- Author
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Yunfei Yi, Chan Feng, Mian Yu, Lin Mei, Meiying Wu, and Wei Tao
- Subjects
Cancer ,Health Sciences ,Molecular Biology ,Biotechnology and Bioengineering ,Chemistry ,Science (General) ,Q1-390 - Abstract
Summary: Efficient gene delivery in an integrated drug delivery system is urgent for multimodal antitumor therapy. Herein, we describe a protocol for constructing a peptide-based siRNA delivery system to achieve tumor vascular normalization and gene silencing in 4T1 cells. We highlighted four major steps, including (1) synthesis of the chimeric peptide, (2) preparation and characterization of PA7R@siRNA micelleplexes, (3) in vitro tube formation assay and transwell cell migration assay, and (4) siRNA transfection in 4T1 cells. This delivery system is expected to be used to silence gene expression, normalize tumor vasculature, and perform other treatments based on the different peptide segments.For complete details on the use and execution of this protocol, please refer to Yi et al. (2022).1 : Publisher’s note: Undertaking any experimental protocol requires adherence to local institutional guidelines for laboratory safety and ethics.
- Published
- 2023
- Full Text
- View/download PDF
29. Reversal of the apparent regiospecificity of NAD(P)H-dependent hydride transfer: The properties of the difluoromethylene group, a carbonyl mimic
- Author
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Leriche, Caroline, Xuemei He, Cheng-wei T. Chang, and Hung-wen Liu
- Subjects
Electrochemistry -- Observations ,Chemical reactions -- Observations ,Methane -- Chemical properties ,Chemistry - Abstract
It is proposed that altering the electrochemical properties of the reaction center can change regiospecificity of hydride transfer catalyzed by a pyridine nucleotide-dependent enzyme. The difluoromethylene functionality has assumed a role as a carbonyl mimic with an apparently reversed regioselectivity of hydride reduction.
- Published
- 2003
30. Facile Fabrication of 3D-Printed Porous Ti6Al4V Scaffolds with a Sr-CaP Coating for Bone Regeneration
- Author
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Shenghui Su, Weidong Chen, Minghui Zheng, Guozan Lu, Wei Tang, Haihong Huang, and Dongbin Qu
- Subjects
Chemistry ,QD1-999 - Published
- 2022
- Full Text
- View/download PDF
31. Characterization of VvmiR166s-Target Modules and Their Interaction Pathways in Modulation of Gibberellic-Acid-Induced Grape Seedless Berries
- Author
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Yunhe Bai, Zhuangwei Wang, Linjia Luo, Xuxian Xuan, Wei Tang, Ziyang Qu, Tianyu Dong, Ziyang Qi, Mucheng Yu, Weimin Wu, Jinggui Fang, and Chen Wang
- Subjects
seedless grape ,gibberellin ,VvmiR166s ,HD-Zip III ,lignin ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Exogenous GA is widely used to efficiently induce grape seedless berry development for significantly improving berry quality. Recently, we found that VvmiR166s are important regulators of response to GA in grapes, but its roles in GA-induced seedless grape berry development remain elusive. Here, the precise sequences of VvmiR166s and their targets VvREV, VvHB15 and VvHOX32 were determined in grape cv. ‘Rosario Bianco’, and the cleavage interactions of VvmiR166s-VvHB15/VvHOX32/VvREV modules and the variations in their cleavage roles were confirmed in grape berries. Exogenous GA treatment significantly induced a change in their expression correlations from positive to negative between VvmiR166s and their target genes at the seeds during the stone-hardening stages (32 DAF–46 DAF) in grape berries, indicating exogenous GA change action modes of VvmiR166s on their targets in this process, in which exogenous GA mainly enhanced the negative regulatory roles of VvmiR166s on VvHB15 among all three VvmiR166s-target pairs. The transient OE-VvmiR166a-h/OE-VvHB15 in tobacco confirmed that out of the VvmiR166 family, VvmiR166h/a/b might be the main factors in modulating lignin synthesis through inhibiting VvHB15, of which VvmiR166h-VvHB15-NtPAL4/NtCCR1/NtCCR2/NtCCoAMT5/NtCOMT1 and VvmiR166a/b-VvHB15-NtCAD1 are the potential key regulatory modules in lignin synthesis. Together with the GA-induced expression modes of VvmiR166s-VvHB15 and genes related to lignin synthesis in grape berries, we revealed that GA might repress lignin synthesis mainly by repressing VvCAD1/VvCCR2/VvPAL2/VvPAL3/Vv4CL/VvLac7 levels via mediating VvmiR166s-VvHB15 modules in GA-induced grape seedless berries. Our findings present a novel insight into the roles of VvmiR66s that are responsive to GA in repressing the lignin synthesis of grape seedless berries, with different lignin-synthesis-enzyme-dependent action pathways in diverse plants, which have important implications for the molecular breeding of high-quality seedless grape berries.
- Published
- 2023
- Full Text
- View/download PDF
32. IbINV Positively Regulates Resistance to Black Rot Disease Caused by Ceratocystis fimbriata in Sweet Potato
- Author
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Dongjing Yang, Xiaofeng Bian, Ho Soo Kim, Rong Jin, Fangyuan Gao, Jingwei Chen, Jukui Ma, Wei Tang, Chengling Zhang, Houjun Sun, Yiping Xie, Zongyun Li, Sang-Soo Kwak, and Daifu Ma
- Subjects
sweet potato ,invertase ,plant growth ,black rot disease ,sugar metabolism ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Black rot disease, caused by Ceratocystis fimbriata Ellis & Halsted, severely affects both plant growth and post-harvest storage of sweet potatoes. Invertase (INV) enzymes play essential roles in hydrolyzing sucrose into glucose and fructose and participate in the regulation of plant defense responses. However, little is known about the functions of INV in the growth and responses to black rot disease in sweet potato. In this study, we identified and characterized an INV-like gene, named IbINV, from sweet potato. IbINV contained a pectin methylesterase-conserved domain. IbINV transcripts were most abundant in the stem and were significantly induced in response to C. fimbriata, salicylic acid, and jasmonic acid treatments. Overexpressing IbINV in sweet potato (OEV plants) led to vigorous growth and high resistance to black rot disease, while the down-regulation of IbINV by RNA interference (RiV plants) resulted in reduced plant growth and high sensitivity to black rot disease. Furthermore, OEV plants contained a decreased sucrose content and increased hexoses content, which might be responsible for the increased INV activities; not surprisingly, RiV plants showed the opposite effects. Taken together, these results indicate that IbINV positively regulates plant growth and black rot disease resistance in sweet potato, mainly by modulating sugar metabolism.
- Published
- 2023
- Full Text
- View/download PDF
33. Adsorption of Phenols from Aqueous Solution with A pH-Sensitive Surfactant-Modified Bentonite
- Author
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Xiangfen Cui, Jingmei Liao, Huaying Liu, Wei Tang, Cheng Tie, Senlin Tian, and Yingjie Li
- Subjects
pH-responsive surfactants ,organic bentonite ,reversible adsorption ,phenolic pollutants ,wastewater ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The presence of organic pollutants in wastewater remains a prominent environmental concern due to the related ecological and health hazards. In response, this study employs an adsorptive methodology to address the removal of phenol and catechol, utilizing an organo-bentonite material modified with a pH-responsive switchable surfactant, dodecyldimethylamine oxide (C12DAO). The synthesized organo-bentonite (C12DAO-Bt) manifests commendable thermostability resulting from thermogravimetric analyses. The adsorption capacities of C12DAO-Bt concerning phenol and catechol intensify with the augmentation of the C12DAO/bentonite mass ratio. The utmost adsorption capacities of 150C12DAO-Bt, deduced through a pseudo-second-order kinetic model, stand at 5.72 mg·g−1 for phenol and 5.55 mg·g−1 for catechol, respectively. Subject to modification by a pH-responsive surfactant, conditions leaning towards weakly acidic and neutral conditions (pH = 6~7) are conducive to the adsorption of phenolic compounds. Conversely, alkaline conditions (pH = 8~9) facilitate the dissociation of adsorbates from adsorbents. The augmentation of cationic strength within the examined scope incites the adsorption procedure while impeding the desorption efficacy. In the case of cationic species with comparable ionic strengths, Na+ exhibited a superior effect on the adsorption–desorption dynamics of phenol, while Ca2+ exerts a more pronounced effect on those of catechol. Moreover, even following five consecutive acid–base regulation cycles, C12DAO-Bt retains a relatively high adsorption capacity and desorption efficacy, which underscores its exceptional regenerative capacity for removing phenolic compounds from wastewater.
- Published
- 2023
- Full Text
- View/download PDF
34. Analysis of Functional Single-Nucleotide Polymorphisms (SNPs) and Leaf Quality in Tea Collection under Nitrogen-Deficient Conditions
- Author
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Lidiia Samarina, Jaroslava Fedorina, Daria Kuzmina, Lyudmila Malyukova, Karina Manakhova, Tatyana Kovalenko, Alexandra Matskiv, Enhua Xia, Wei Tong, Zhaoliang Zhang, Alexey Ryndin, Yuriy L. Orlov, and Elena K. Khlestkina
- Subjects
Camellia sinensis ,candidate genes ,caffeine ,catechin ,germplasm collection ,SNP effect ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
This study discusses the genetic mutations that have a significant association with economically important traits that would benefit tea breeders. The purpose of this study was to analyze the leaf quality and SNPs in quality-related genes in the tea plant collection of 20 mutant genotypes growing without nitrogen fertilizers. Leaf N-content, catechins, L-theanine, and caffeine contents were analyzed in dry leaves via HPLC. Additionally, the photochemical yield, electron transport efficiency, and non-photochemical quenching were analyzed using PAM-fluorimetry. The next generation pooled amplicon–sequencing approach was used for SNPs-calling in 30 key genes related to N metabolism and leaf quality. The leaf N content varied significantly among genotypes (p ≤ 0.05) from 2.3 to 3.7% of dry mass. The caffeine content varied from 0.7 to 11.7 mg g−1, and the L-theanine content varied from 0.2 to 5.8 mg g−1 dry leaf mass. Significant positive correlations were detected between the nitrogen content and biochemical parameters such as theanine, caffeine, and most of the catechins. However, significant negative correlations were observed between the photosynthetic parameters (Y, ETR, Fv/Fm) and several biochemical compounds, including rutin, Quercetin-3-O-glucoside, Kaempferol-3-O-rutinoside, Kaempferol-3-O-glucoside, Theaflavin-3′-gallate, gallic acid. From our SNP-analysis, three SNPs in WRKY57 were detected in all genotypes with a low N content. Moreover, 29 SNPs with a high or moderate effect were specific for #316 (high N-content, high quality) or #507 (low N-content, low quality). The use of a linear regression model revealed 16 significant associations; theaflavin, L-theanine, and ECG were associated with several SNPs of the following genes: ANSa, DFRa, GDH2, 4CL, AlaAT1, MYB4, LHT1, F3′5′Hb, UFGTa. Among them, seven SNPs of moderate effect led to changes in the amino acid contents in the final proteins of the following genes: ANSa, GDH2, 4Cl, F3′5′Hb, UFGTa. These results will be useful for further evaluations of the important SNPs and will help to provide a better understanding of the mechanisms of nitrogen uptake efficiency in tree crops.
- Published
- 2023
- Full Text
- View/download PDF
35. Path Planning for Conformal Antenna Surface Detection Based on Improved Genetic Algorithm
- Author
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Yifan Ding, Xiaodong Du, Changrui Wang, Wei Tian, Chao Deng, Ke Li, and Zihang Wang
- Subjects
traveling salesman problem ,improved genetic algorithm ,probability-based four-nearest-neighbor method ,historical optimal population ,conformal antenna ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The conformal antenna is a precision device installed on the wing of an aircraft, and its components are distributed on a curved surface. Quality detection is required after assembly. In solving the path planning problem for conformal antenna surface detection, the traditional genetic algorithm faces problems such as slow convergence and easily falling into a local optimal solution. To solve this problem, an improved genetic algorithm combining the historical optimal population (CHOP-IGA) is proposed. First, the algorithm uses the probability-based four-nearest-neighbor method to construct an initial population. Subsequently, the probabilities of the crossover and mutation operators are dynamically adjusted. Next, the algorithm applies the crossover and mutation operators to the population and performs mutation operations on each individual of the historical optimal population. Then, the fitness value is calculated and the next generation of individuals is selected from the parent, offspring, and historical optimal populations according to the elite selection strategy. Finally, the current best fitness is checked to determine whether updating the historical optimal population is necessary. When the termination condition is satisfied, the algorithm outputs the optimal result. Experiments showed that the algorithm satisfactorily solved the path planning problem for conformal antenna surface detection, with a 48.44% improvement in detection efficiency.
- Published
- 2023
- Full Text
- View/download PDF
36. Evolution and Expression of the Expansin Genes in Emmer Wheat
- Author
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Ming Li, Tao Liu, Rui Cao, Qibin Cao, Wei Tong, and Weining Song
- Subjects
emmer wheat ,expansin gene family ,evolution ,expression pattern ,haplotypes ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
Expansin proteins, a crucial class of intracellular proteins, are known to play a vital role in facilitating processes like cell wall relaxation and cell growth. Recent discoveries have revealed that expansin proteins also have significant functions in plant growth, development, and response to resistance. However, the expansin gene family, particularly in emmer wheat, has not been thoroughly studied, particularly in terms of evolution. In this study, we identified 63 TdEXPs and 49 TtEXPs from the latest genome versions of wild emmer wheat (WEW) and durum wheat (DW), respectively. The physicochemical properties of the encoded expansin proteins exhibited minimal differences, and the gene structures remained relatively conserved. Phylogenetic analysis categorized the proteins into three subfamilies, namely EXPA, EXPB, and EXLA, in addition to the EXLB subfamily. Furthermore, codon preference analysis revealed an increased usage frequency of the nucleotide “T” in expansin proteins throughout the evolution of WEW and DW. Collinearity analysis demonstrated higher orthology between the expansin proteins of WEW and DW, with a Ka/Ks ratio ranging from 0.4173 to 0.9494, indicating purifying selection during the evolution from WEW to DW. Haplotype analysis of the expansin gene family identified five genes in which certain haplotypes gradually became dominant over the course of evolution, enabling adaptation for survival and improvement. Expression pattern analysis indicated tissue-specific expression of expansin genes in emmer wheat, and some of these genes were quantified through qRT-PCR to assess their response to salt stress. These comprehensive findings present the first systematic analysis of the expansin protein gene family during the evolution from WEW to DW, providing a foundation for further understanding the functions and biological roles of expansin protein genes in emmer wheat.
- Published
- 2023
- Full Text
- View/download PDF
37. The Development of Carbon-Carbon Composite Cages for Rolling Element Bearings
- Author
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Wei T. Shih, Lewis Rosado, Jeffrey Brown, and Nelson H. Forster
- Subjects
Bearing (mechanical) ,Materials science ,Mechanical Engineering ,Composite number ,Reinforced carbon–carbon ,chemistry.chemical_element ,Surfaces and Interfaces ,Thermal expansion ,Surfaces, Coatings and Films ,law.invention ,Condensed Matter::Soft Condensed Matter ,Thermal conductivity ,chemistry ,Mechanics of Materials ,law ,Heat generation ,Physics::Atomic and Molecular Clusters ,Lubrication ,Composite material ,Carbon - Abstract
This paper highlights the development of carbon matrix-carbon fiber (C-C) composite bearing cages for high temperature gas turbine applications. Benefits of C-C cages under high-speed, high-temperature conditions are documented with experimental results. The experimental results show that C-C cages offer substantial reduction in heat generation compared to metal cages at the same operating conditions, and C-C cages enable much higher DN operation in the absence of liquid lubrication. The improved performance of C-C cages over conventional metal cages is largely attributed to the inherent properties of C-C composites: 1. Low density to reduce centrifugal speed effects; 2. Excellent thermal conductivity for a non-metal; 3. Low friction under marginal lubrication conditions; 4. Low wear rates compared to other self-lubricating cage materials; and 5. Low coefficient of thermal expansion to avoid seizure in high thermal gradient conditions. Presented at the 56th Annual Meeting in Orlando, Florida May 20–24, 2001
- Published
- 2002
38. Light controlled drug-based supramolecular polymer self-assemblies for efficient antibacterial manipulation
- Author
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Chengfei Liu, Zuoting Yang, Xin Song, Yongchao Qian, Hongbin Huo, Jia He, JuAn Zhang, Zhelin Zhang, Menghan Shi, Jun Pang, Baoliang Zhang, and Wei Tian
- Subjects
Supramolecular polymer ,Drug self-delivery ,Self-assemblies ,Light-responsiveness ,Antibacterial ,Chemistry ,QD1-999 - Abstract
The infections and diseases caused by harmful bacteria are regarded as the worldwide health-threatening issue. The most antibiotics-based delivery systems restricted the controlled drug release at specific infection sites due to the stable chemical conjugation, thus largely compromising the treatment effectiveness. Herein, we report the construction of light controlled drug-based supramolecular polymer (LDSP), which is endowed the “switch on” function for realizing the controllable antibiotics released in specific sites. LDSP was first formed based on the host-guest interaction between β-cyclodextrin units grafted hyaluronic acid chain (HA-CD) and azobenzene moiety linked by two enoxacin units (Azo-(Eno)2), and could further self-assemble into light controlled drug-based supramolecular polymer self-assemblies (LDSPSAs). Under the UV light irradiation, the “switch on” function of LDSPSAs could be effectively turned on at the specific infected tissues due to the smartly dissociated host-guest interaction, facilitating the controlled release of the hydrophobic Azo-(Eno)2 to interact with bacteria for efficient antibacterial effect. The biological evaluation demonstrated that LDSPSAs achieved good antibacterial efficiency and well biosafety.
- Published
- 2022
- Full Text
- View/download PDF
39. The Conformational Change with Temperature of End Group Sequences of Low Molecular Weight Polyethylene
- Author
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Ryozo Kitamaru, Leo Mandelkern, Takahiko Nakaoki, Rufina G. Alamo, and Wei T Huang
- Subjects
chemistry.chemical_compound ,End-group ,Conformational change ,Crystallography ,Polymers and Plastics ,chemistry ,Materials Chemistry ,Solid-state ,Organic chemistry ,sense organs ,Polyethylene ,skin and connective tissue diseases ,Oligomer - Abstract
The Conformational Change with Temperature of End Group Sequences of Low Molecular Weight Polyethylene
- Published
- 2000
40. Photo-Fenton Process over an Fe-Free 3%-CuO/Sr0.76Ce0.16WO4 Photocatalyst under Simulated Sunlight
- Author
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Mingyan Fu, Jia Yang, Xiaorui Sun, Wei Tian, Guihua Yin, Sheng Tian, Mingdan Tan, Hongfu Liu, Xiaofeng Xing, and Huisheng Huang
- Subjects
Chemistry ,QD1-999 - Published
- 2021
- Full Text
- View/download PDF
41. Effect of polymer binders in screen printing technique of silver pastes
- Author
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Rong H. Guo, Chi C. Hua, Wei-T. Chen, Cheng-L. Shih, Chien P. Hsu, and Tien-I Chang
- Subjects
chemistry.chemical_classification ,Materials science ,Polymers and Plastics ,Organic Chemistry ,Substrate (printing) ,Polymer ,Aspect ratio (image) ,chemistry ,Electrical resistance and conductance ,Screen printing ,Materials Chemistry ,Wafer ,Crystalline silicon ,Composite material ,Electrical conductor - Abstract
Silver pastes are widely used in the front-side metallization of crystalline silicon solar cells via screen printing technique, with an aim to print conductive lines bearing a high aspect ratio which helps reduce electric resistance and improve the overall device efficiency. Rheological features are very important to describe the paste behaviors during screen printing as well as in the formation of fine conductive lines on wafer substrate. In this study, three different silver pastes and two individual components (i.e., silver powder and polymer binder) have been systematically investigated, revealing how the altering rheological features due to the addition of polymer binders—despite a typically low weight percentage—can significantly impact the (simulated) printing quality of a silver paste. The results point to the imperative need to delve into the effects of polymer species, polymer molecular weight and its weight percentage in order to systematically improve the printing performance of metal pastes without altering its main (powders) component.
- Published
- 2013
42. Mesobiliverdin IXα Enhances Rat Pancreatic Islet Yield and Function
- Author
-
Taihei eIto, Dong eChen, Cheng-Wei T. Chang, Takashi eKenmochi, Tomonori eSaito, Satoshi eSuzuki, Jon Y Takemoto, and Frontiers Media
- Subjects
endocrine system ,Allograft transplantation ,medicine.medical_specialty ,endocrine system diseases ,medicine.medical_treatment ,Mesobiliverdin ,Biochemistry ,chemistry.chemical_compound ,Internal medicine ,Medicine ,Pharmacology (medical) ,Original Research ,anti-inflammatory ,Pharmacology ,geography ,mesobiliverdin ,pancreatic islets ,Biliverdin ,geography.geographical_feature_category ,business.industry ,islet transplantation ,Insulin ,Pancreatic islets ,lcsh:RM1-950 ,Biliverdin reductase ,biliverdin ,Islet ,Chemistry ,lcsh:Therapeutics. Pharmacology ,Endocrinology ,medicine.anatomical_structure ,chemistry ,business ,Function (biology) - Abstract
The aims of this study were to produce mesobiliverdin IXα, an analog of anti-inflammatory biliverdin IXα and to test its ability to enhance rat pancreatic islet yield for allograft transplantation into diabetic recipients. Mesobiliverdin IXα was synthesized from phycocyanobilin derived from cyanobacteria, and its identity and purity were analyzed by chromatographic and spectroscopic methods. Mesobiliverdin IXα was a substrate for human NADPH biliverdin reductase. Excised Lewis rat pancreata infused with mesobiliverdin IXα and biliverdin IXα-HCl (1 – 100 μM) yielded islet equivalents as high as 86.7% and 36.5%, respectively, above those from non-treated controls, and the islets showed a high degree of viability based on dithizone staining. When transplanted into livers of streptozotocin-induced diabetic rats, islets from pancreata infused with mesobiliverdin IXα lowered non-fasting blood glucose levels in 55.6% of the recipients and in 22.2% of control recipients. In intravenous glucose tolerance tests, fasting blood glucose levels of 56 post-operative day recipients with islets from mesobiliverdin IXα infused pancreata were lower than those for controls and showed responses that indicate recovery of insulin-dependent function. In conclusion, mesobiliverdin IXα infusion of pancreata enhanced yields of functional islets capable of reversing insulin dysfunction in type 2 diabetic recipients. Since its production is scalable, mesobiliverdin IXα has clinical potential as a protectant of pancreatic islets for allograft transplantation.
- Published
- 2013
43. Balloon: An Elastic Data Management Strategy for Interlaced Magnetic Recording
- Author
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Chi Zhang, Song Liu, Fangxing Yu, Menghan Li, Wei Tang, Fei Liu, and Weiguo Wu
- Subjects
interlaced magnetic recording (IMR) ,hard disks ,data layout ,data shuffling ,interlaced translation layer (ITL) ,storage management ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Recently, the emerging technology known as Interlaced Magnetic Recording (IMR) has been receiving widespread attention from both industry and academia. IMR-based disks incorporate interlaced track layouts and energy-assisted techniques to dramatically increase areal densities. The interlaced track layout means that in-place updates to the bottom track require rewriting the adjacent top track to ensure data consistency. However, at high disk utilization, frequent track rewrites degrade disk performance. To address this problem, we propose a solution called Balloon to reduce the frequency of track rewrites. First, an adaptive write interference data placement policy is introduced, which judiciously places data on tracks with low rewrite probability to avoid unnecessary rewrites. Next, an on-demand data shuffling mechanism is designed to reduce user-requests write latency by implicitly migrating data and promptly swapping tracks with high update block coverage to the top track. Finally, a write-interference-free persistent buffer design is proposed. This design dynamically adjusts buffer admission constraints and selectively evicts data blocks to improve the cooperation between data placement and data shuffling. Evaluation results show that Balloon significantly improves the write performance of IMR-based disks at medium and high utilization compared with state-of-the-art studies.
- Published
- 2023
- Full Text
- View/download PDF
44. Revealing the Roles of Cu/Ba on Ce-Based Passive NOx Adsorbers
- Author
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Mingming Pei, Yuxin Fan, Haidi Xu, Zhihua Lian, Wei Tan, Jianli Wang, and Yaoqiang Chen
- Subjects
passive NOx adsorbers ,NOx ,ceria oxides ,barium ,copper ,Chemical technology ,TP1-1185 ,Chemistry ,QD1-999 - Abstract
At present, passive NOx adsorbers (PNAs) represent one of the most effective technologies for addressing NOx emissions from diesel engines during cold-start periods. Conventional PNAs, which primarily consist of noble metals (such as Pt, Pd, and Ag) loaded on metal oxides or zeolites, share the common drawback of high production costs. Consequently, developing low-cost PNAs with outstanding NOx storage performance remains a significant challenge. In this study, a series of CuxBa5Ce adsorbents were synthesized using the impregnation method, and a monolithic adsorbent was employed to evaluate NOx storage and release performance. Techniques such as XRD, UV-Vis DRs, H2-TPR, XPS, and in situ DRIFTs confirmed the crucial roles of Cu and Ba in NOx storage and release. Specifically, the incorporation of Cu into CeO2 enhanced NOx storage performance. Moreover, in the Cu3Ba5Ce adsorbent, the addition of Ba not only introduced new storage sites and altered the stability of NOx adsorption species but also helped prevent the aggregation of CuO, thereby prolonging the complete NOx storage duration and satisfying desorption temperature requirements. The Cu3Ba5Ce adsorbent exhibited the most favorable NOx storage performance, including a complete NOx storage time of 135 s and a NOx storage efficiency exceeding 50% at 80 °C over a 10 min period. While PNAs loaded with noble metals, such as Pd/CeO2 and Pt/CeO2, exhibited NOx storage efficiencies below 50% after adsorbing for 5 min at 80 °C. Therefore, this research offered a crucial strategy for developing non-noble-metal-loaded, Ce-based PNAs.
- Published
- 2023
- Full Text
- View/download PDF
45. Design and Research of Intelligent Assembly and Welding Equipment for Three-Dimensional Circuit
- Author
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Zihang Wang, Xiaodong Du, Changrui Wang, Wei Tian, Chao Deng, Ke Li, Yifan Ding, and Wenhe Liao
- Subjects
intelligent assembly equipment ,radar equipment ,conformal antenna ,three-dimensional stereo circuit ,high precision ,high efficiency ,Technology ,Engineering (General). Civil engineering (General) ,TA1-2040 ,Biology (General) ,QH301-705.5 ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
The processing of the three-dimensional circuit on the surface of conformal antennas is mainly performed via manual processing. At present, there is no automatic intelligent equipment for the processing of a similar small-sized circuit with variable curvature in China. Therefore, a high-precision, automated, full-process manufacturing method for three-dimensional circuits with flexible surfaces on conformal antennas of radar equipment has been proposed to improve processing quality and manufacturing efficiency. The processing relationship between solder paste spraying, resistor mounting, and laser welding in the flexible three-dimensional circuit manufacturing process was analyzed. The structure of the new conformal antenna three-dimensional circuit intelligent manufacturing equipment was determined, and simulation verification of the three-dimensional circuit processing was performed using Vericut. The optimal processing parameters were selected based on solid experiments. This method meets the electronic assembly requirements of radar equipment and fills the domestic gap.
- Published
- 2023
- Full Text
- View/download PDF
46. Review of Photochemical Activity of Dissolved Black Carbon in Aquatic Environments: Primary Influencing Factors and Mechanisms
- Author
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Huaying Liu, Yina Tu, Wei Tang, Weilin Wu, and Yingjie Li
- Subjects
dissolved black carbon ,photochemical activity ,qualitative and quantitative analysis ,water-soluble components ,Physics ,QC1-999 ,Chemistry ,QD1-999 - Abstract
Dissolved black carbon (DBC), the particular component of black carbon that can be dissolved in the water, which accounts for ~10% of the organic carbon cycle in the earth’s water body, is an essential member of the dissolved organic matter (DOM) pool. In contrast to DOM, DBC has a higher proportion of conjugated benzene rings, which can more efficiently encourage the degradation of organic micropollutants in the aquatic environment or more rapidly generate reactive oxygen species to photodegrade the organic micropollutants. Therefore, it is of great significance to study the changes and mechanisms of DBC photochemical activity affected by different factors in the water environment. Our work reviewed the main influencing factors and mechanisms of the photochemical activity of DBC. It focuses on the methodologies for the quantitative and qualitative investigation of the photochemical activity of DBC, the impact of the biomass source, the pyrolysis temperature of biochar, and the primary water environmental parameters on the photochemical activity of DBC and the indirect photodegradation of pollutants. Based on this, a potential future study of DBC photochemical activity has been prospected.
- Published
- 2023
- Full Text
- View/download PDF
47. Chitosan-g-MPEG-modified alginate/chitosan hydrogel microcapsules: a quantitative study of the effect of polymer architecture on the resistance to protein adsorption
- Author
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Hong G Xie, Jing Zhu, Wei Y. Xie, Wei T Yu, Xiu D. Liu, Xiao J. Ma, and Jia N Zheng
- Subjects
Alginates ,Polymer architecture ,Capsules ,Polyethylene Glycols ,Chitosan ,chemistry.chemical_compound ,Adsorption ,Glucuronic Acid ,Polymer chemistry ,Electrochemistry ,Animals ,General Materials Science ,Cell encapsulation ,Spectroscopy ,Aldehydes ,Hexuronic Acids ,Chemical modification ,Hydrogels ,Surfaces and Interfaces ,Condensed Matter Physics ,Polyelectrolyte ,Molecular Weight ,chemistry ,Chemical engineering ,Immunoglobulin G ,Chromatography, Gel ,Cattle ,Ethylene glycol ,Protein adsorption - Abstract
The chemical modification of the alginate/chitosan/alginate (ACA) hydrogel microcapsule with methoxy poly(ethylene glycol) (MPEG) was investigated to reduce nonspecific protein adsorption and improve biocompatibility in vivo. The graft copolymer chitosan-g-MPEG (CS-g-MPEG) was synthesized, and then alginate/chitosan/alginate/CS-g-MPEG (ACAC(PEG)) multilayer hydrogel microcapsules were fabricated by the layer-by-layer (LBL) polyelectrolyte self-assembly method. A quantitative study of the modification was carried out by the gel permeation chromatography (GPC) technique, and protein adsorption on the modified microcapsules was also investigated. The results showed that the apparent graft density of the MPEG side chain on the microcapsules decreased with increases in the degree of substitution (DS) and the MPEG chain length. During the binding process, the apparent graft density of CS-g-MPEG showed rapid growth-plateau-rapid growth behavior. CS-g-MPEG was not only bound to the surface but also penetrated a certain depth into the microcapsule membranes. The copolymers that penetrated the microcapsules made a smaller contribution to protein repulsion than did the copolymers on the surfaces of the microcapsules. The protein repulsion ability decreased with the increase in DS from 7 to 29% with the same chain length of MPEG 2K. CS-g-MPEG with MPEG 2K was more effective at protein repulsion than CS-g-MPEG with MPEG 550, having a similar DS below 20%. In this study, the microcapsules modified with CS-g-MPEG2K-DS7% had the lowest IgG adsorption of 3.0 ± 0.6 μg/cm(2), a reduction of 61% compared to that on the chitosan surface.
- Published
- 2010
48. Antioxidant, anti-lipidemic, hypoglycemic and antiproliferative effects of phenolics from Cortex Mori Radicis
- Author
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Chao Li, Yao Peng, Wei Tang, Teng Li, Mansour K. Gatasheh, Rabab Ahmed Rasheed, Junning Fu, Juping He, Wei-dong Wang, Yingbin Shen, Yichao Yang, Yongsheng Chen, and Arshad Mehmood Abbasi
- Subjects
Cortex Mori Radicis ,Phenolics ,Ultrasonic ,Antioxidant effect ,Enzyme inhibitory effect ,Antiproliferative effect ,Chemistry ,QD1-999 - Abstract
Cortex Mori Radicis (CMR) is enriched in various phenolics, this study aimed to estimate the antioxidant effect, enzyme (lipase, α-amylase, α-glucosidase and acetyl-cholinesterase) inhibition and the anti-proliferative effect of the phenolic compounds in CMR. However, the amount of these compounds obtained from CMR is highly dependent on the processing conditions. In this study, the processing parameters of extracting the phenolics from CMR using ultrasonic technique pooled with high-speed shearing extraction (UTPHSE) were optimized. Subsequently, the phenolics from Cortex Mori Radicis (PCMR) were purified using AB-8 macroporous resin, and their chemical analysis, antioxidant, enzyme inhibition, and antiproliferative activities were studied. Based on our findings, the optimal parameters of UTPHSE were: L/S ratio 25.8:1 (mL/g), voltage 81.0 V, ultrasonic temperature 51.8 ℃ and ultrasonic time 289 s. And under the optimal extraction conditions, the extraction rate of the PCMR was 0.531 ± 0.004%. Compared with PCMR, the contents of “total phenolics, flavonoids, flavonols, flavanols and phenolic acids” increased 2.30, 2.67, 2.59, 3.63 and 2.72 times in the purified phenolics from Cortex Mori Radicis (PPCMR), respectively. In addition, PPCMR depicted significant DPPH, ABTS+ and superoxide anion radicals’ scavenging capability, reducing power, ferric ion reducing antioxidant power (FRAP) and remarkable inhibitory activities on “lipase, alpha-amylase, alpha-glucosidase, and the proliferation of HeLa, HepG2 and NCI-H460”. At the same time, the morphological changes of HeLa, HepG2 and NCI-H460 cells suggested that PPCMR could effectively inhibit the proliferation of tumor cells in vitro. Therefore, PPCMR have good potential as natural antioxidants, antilipidemic, hypoglycemic, and antineoplastic agents in functional foods and pharmaceuticals.
- Published
- 2022
- Full Text
- View/download PDF
49. Application of reutilization technology to waste from liquid crystal display (LCD) industry
- Author
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Wei T. Liu and Kung C. Li
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Conservation of Natural Resources ,Environmental Engineering ,Materials science ,Aggregate (composite) ,Absorption of water ,Waste management ,chemistry.chemical_element ,General Medicine ,Waste treatment ,chemistry ,Wastewater ,Fluorine ,Industry ,Leachate ,Porosity ,Specific gravity - Abstract
This investigation studies the recycling utility of two major waste products from the liquid crystal display (LCD) industry, panel glass and calcium fluoride sludge, which remain after the treatment of waste water. Waste panel glass was mixed with calcium fluoride sludge in various ratios and then subject to conditioning and melting treatment in order to yield glass-ceramics. Heavy metal leaching tests indicated that reductive conditions lowered the heavy metal concentrations in the leachate to an order of magnitude below that in the waste glass and sludge. A 5:5 (wt%) mixture of glass and sludge melted at 1200 degrees C for 60 min achieves a specific gravity, water absorption, unit mass, porosity ratio, and soundness that meet the American Society for Testing and Materials (ASTM) standard for fine aggregates. Therefore, waste panel glass can indeed be efficiently recycled into a useful construction material.
- Published
- 2010
50. Extraction Optimization, Characterization and Biological Activities of Polysaccharide Extracts from Nymphaea hybrid
- Author
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Hui-Min Liu, Wei Tang, Sheng-Nan Lei, Yun Zhang, Ming-Yan Cheng, Qing-Lei Liu, and Wei Wang
- Subjects
Nymphaea hybrid ,extraction ,antioxidant ,bioactivities ,Biology (General) ,QH301-705.5 ,Chemistry ,QD1-999 - Abstract
In this study, polysaccharide–rich Nymphaea hybrid extracts (NHE) were obtained using the ultrasound-assisted cellulase extraction (UCE) method optimized by response surface methodology (RSM). The structural properties and thermal stability of NHE were characterized by Fourier-transform infrared (FT–IR), high–performance liquid chromatography (HPLC) and thermogravimetry–derivative thermogravimetry (TG–DTG) analysis, respectively. Moreover, the bioactivities of NHE, including the antioxidant, anti–inflammatory, whitening and scratch healing activities were evaluated by different in vitro assays. NHE conveyed a good ability to scavenge against the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals and inhibit the hyaluronidase activity. NHE can effectively protect the HaCaT cells against oxidative damage by inhibiting the intracellular reactive oxygen species (ROS) production in the H2O2 stimulation assays and promoting the proliferation and migration in the scratch assays. In addition, NHE was proven to inhibit melanin production in B16 cells. Collectively, the above results seem to be the evidence needed to promote the potential of NHE to be regarded as a new functional raw material in the cosmetics or food industries.
- Published
- 2023
- Full Text
- View/download PDF
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