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Study of Metal-Induced Effects of cd, Sb and Zn on d.c./a.c. conduction and Photoconduction in Binary Se70Te30 Glass

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JOURNAL OF ELEcTRONIc MATERIALS 2020年第1期49卷 861-868页

作者： Saraswat, Shobhit Tomar, V. K. Mehta, N. Dahshan, A. GLA Univ Inst Engn & Technol Dept Elect & Commun Mathura India Banaras Hindu Univ Inst Sci Dept Phys Varanasi 221005 Uttar Pradesh India King Khalid Univ Fac Sci Dept Phys POB 9004 Abha Saudi Arabia Port Said Univ Fac Sci Dept Phys Port Said Egypt

This paper reports the temperature dependence of d.c. and a.c. conductivity in the glassy alloys of Se70Te30 and Se70Te28M2 (M = cd, Sb, Zn). The role of the cd, Sb, Zn elements as foreign atoms has been examined on the d.c./a.c. conduction and photoconduction in binary Se70Te30 glass. These multi-component chalcogenide glasses have been prepared by conventional, cost-effective and well-known melt-quench technique. Thermally activated a.c. conduction shows the presence of the compensation effect that is confirmed by the Meyer-Neldel relation between the associated activation energy and the pre-factor of a.c. conductivity. The metal-induced effects of cd, Sb, Zn on the photosensitivity of parent glass are also discussed.

关键词： Glass d c conductivity photosensitivity

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Fecl3/c as an efficient catalyst for Ferrier rearrangement of 3,4,6-tri-O-Benzyl-D-glucal

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JOURNAL OF cARBOHYDRATE cHEMISTRY 2020年第5-6期39卷 232-249页

作者： Mei, Yuling Dong, Youxian Li, Juan Zhang, Bo Sun, Guosheng Zhou, Jiafen Si, Wenshuai Han, Yiwen Wu, Zhenliang Zhang, Jianbo East China Normal Univ Sch Chem & Mol Engn 500 Dongchuan Rd Shanghai 200241 Peoples R China

Fecl3/c was used as an efficient and convenient promoter for glycosylation through Ferrier-type rearrangement of 3,4,6-tri-O-benzyl-D-glucal, which is a relatively unreactive substrate for this type of reaction. The method was applicable to a wide range of alcohols, especially phenols. A series of 2,3-unsaturated-O-glucosides were prepared efficiently (47-92%) by this method under mild conditions.

关键词： Fecl3 c Ferrier rearrangement promoter glycosylation 346-tri-O-benzyl-D-glucal

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Fabrication of Zrc/ZrB₂/c composites Having High Mechanical Properties at Elevated Temperatures

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Materials Sciences and Applications 2022年第4期13卷 232-248页

作者： Kai Matsumoto Masaki Kato Ken Hirota Toshiyuki Nishimura Department of Molecular Chemistry & Biochemistry Faculty of Science & Engineering Doshisha University Kyotanabe Japan National Institute for Materials Science Tsukuba Japan

Ultra-high temperature ceramics (UHTcs) are most recently getting much attention for structural parts of hypersonic missiles with their cruising speed of more than Mach 5. Most of the UHTcs are poor sinterability carbides, nitrides, and borides. Therefore, they have been studied and developed for a long time. However, there are still many problems to solve. In this paper, based on the solid-state reaction presented as an equation of (x + y)·Zrc + 2·y·B → x·Zrc + y·ZrB₂ + y·c, three-phase Zrc/ZrB₂/c composites have been fabricated from Zrc and amorphous B powders using pulsed electric-current pressure sintering at 1373 to 2173 K for 6.0 × 10² s under 50 MPa in a vacuum. Zrc/ZrB2/c = 30/70/c~70/30/c vol% composites with the relative densities D_r of 96.6 to 98.7% were obtained at 2073 K. The 60/40/c vol% composite revealed high bending strength σ_b (554 MPa), Vickers hardness H_v (19.2 GPa) and moderate fracture toughness K_Ic (5.25 MPa·m^1/2) at room temperature. Furthermore, all composites showed elastic deformation up to 1873 K and revealed σ_b more than 600 MPa at this temperature, in addition, some composites showed higher σ_b than 900 MPa at the same temperature. These high mechanical behaviors are discussed with those of the simple binary Zrc/ZrB₂ composites which were fabricated under the same conditions except for their starting materials. The best mechanical properties of binary composites were σ_b (474 MPa), H_v (18.5 GPa), and K_Ic (4.45 MPa·m^1/2) at room temperature, and σ_b of 400 - 700 MPa at 1873 K. Overall, three-phase composites, nevertheless including soft carbon, have higher mechanical properties than the binary composites.

关键词： Zrc ZrB2 c composites Pulsed Electric-current Pressure Sintering Mechanical Properties

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comprehensive transcriptomic analysis reveals insights into the gill response to hypoxia and Poly I:c in Qihe crucian carp carassius auratus

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AQUAcULTURE REPORTS 2022年 24卷

作者： Di, Guilan Li, Hui Zhao, Yanjing Lin, Yan Lan, Di Kong, Xianghui chen, Xinhua Fujian Agr & Forestry Univ Inst Oceanol Coll Marine Sci Key Lab Marine Biotechnol Fujian Prov Fuzhou 350002 Peoples R China Henan Normal Univ Coll Fisheries Xinxiang 453007 Peoples R China Fuzhou Inst Technol Dept Biotechnol Fuzhou 350506 Peoples R China Qingdao Natl Lab Marine Sci & Technol Lab Marine Biol & Biotechnol Qingdao 266071 Peoples R China Henan Normal Univ Coll Fisheries 46 Jianshe Rd Xinxiang 453007 Peoples R China

Hypoxia occurrence is potentiated by eutrophication caused by human activities and it may be the most dramatically increasing environmental factor as a result of the climate change-led increasing temperatures. The crucian carp carassius auratus is an important aquaculture economical freshwater species and is also a potential model for the study of physiological adaptation. However, the transcriptomics and genomics data available for this species are still scarce. The gills of fish are the major organ of hypoxia and other stresses. In this study, we studied the effect of the exposure to hypoxia (1.0 mg O2/L for 7 d) and 2 mg/mL Poly I:c on the gene expression of the gills of carassius auratus using the Illumina sequencing platform. comparison of the gene expression levels between the experimental and control groups showed differentially expressed genes (DEGs). The DEGs were mainly annotated into glycolysis, oxidative phosphorylation and immune system categories based on the KEGG database. In glycolysis pathway, lactate dehydrogenase, malate dehydrogenase, glyceraldehyde 3-phosphate dehydrogenase, enolase and succinate dehydrogenase were identified. In addition, the DEGs were enriched in the immune-related pathway functions, including pattern recognition receptor (PRR), antigen processing and presentation, B cell and T cell receptor signaling pathways, natural killer (NK) cell mediated cytotoxicity, Fc gamma R-mediated phagocytosis, and the JAK-STAT, p53 and cytokines signaling pathways. This study also produced potential hypoxia biomarkers including FOS, JUN B, lysosomal acid lipase, and HIF-1 alpha. HIF-1 signaling pathway was significantly down-regulated after hypoxia and Poly I: c exposure. Hence, the data generated here may offer a valuable resource information for the further study of the immune response and also provide improved strategies against hypoxia and Poly I:c in teleost fish.

关键词： Transcriptome carassius auratus Hypoxia Gill Poly I c

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A cutting Force Prediction Model, Experimental Studies, and Optimization of cutting Parameters for Rotary Ultrasonic Face Milling of c/Sic composites

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APPLIED cOMPOSITE MATERIALS 2020年第4期27卷 407-431页

作者： Islam, Shafiul Yuan, Songmei Li, Zhen Beihang Univ Beijing Engn Technol Res Ctr High Efficient & Gre Sch Mech Engn & Automat Beijing 100191 Peoples R China

ceramic matrix composites of type c/Sic have great potential because of their excellent properties such as high specific strength, high specific rigidity, high-temperature endurance, and superior wear resistance. However, the machining of c/Sic is still challenging to achieve desired efficiency and quality due to their heterogeneous, anisotropic, and varying thermal properties. Rotary ultrasonic machining (RUM) is considered as a highly feasible technology for advanced materials. cutting force prediction in RUM can help to optimize input variables and reduce processing defects in composite materials. In this research, a mathematical axial cutting force model has been developed based on the indentation fracture theory of material removal mechanism considering penetration trajectory and energy conservation theorem for rotary ultrasonic face milling (RUFM) of c/Sic composites and validated through designed sets of experiments. Experimental results were found to be in good agreement with theoretically simulated results having less than 15% error. Therefore, this theoretical model can be effectively applied to predict the axial cutting forces during RUFM of c/Sic. The surface roughness of the workpiece materials was investigated after machining. The relationships of axial cutting force and surface roughness with cutting parameters, including spindle speed, feed rate, and cutting depth, were also investigated. In order to identify the influence of cutting parameters on the RUFM process, correlation analysis was applied. In addition, response surface methodology was employed to optimize the cutting parameters.

关键词： c Sic composites Rotary ultrasonic face milling A predictive cutting force model Surface roughness Optimization of cutting parameters

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Effect of the cagW-based gene vaccine on the immunologic properties of BALB/c mouse: an efficient candidate for Helicobacter pylori DNA vaccine

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JOURNAL OF NANOBIOTEcHNOLOGY 2020年第1期18卷 63-63页

作者： chehelgerdi, Mohammad Doosti, Abbas Islamic Azad Univ Shahrekord Branch Young Researchers & Elite Club Shahrekord Iran Islamic Azad Univ Shahrekord Branch Biotechnol Res Ctr Shahrekord Iran

Background Helicobacter pylori (H. pylori) infect more than half of the world population, and they cause different serious diseases such as gastric carcinomas. This study aims to design a vaccine on the basis of cagW against H. pylori infection. After pcDNA3.1 (+)-cagW-cS-NPs complex is produced, it will be administered into the muscles of healthy BALB/c mice in order to study the effect of this DNA vaccine on the interleukin status of mice, representing its effect on the immune system. After that, the results will be compared with the control groups comprising the administration of cagW-pcDNA3.1 (+) vaccine, the administration of chitosan and the administration of PBS in the muscles of mice. Methods The cagW gene of H. pylori was amplified by employing PcR, whose product was then cloned into the pcDNA3.1 (+) vector, and this cloning was confirmed by PcR and BamHI/EcoRV restriction enzyme digestion. cagW gene DNA vaccine was encapsulated in chitosan nanoparticles (pcDNA3.1 (+)-cagW-cS-NPs) using a complex coacervation method. The stability and in vitro expression of chitosan nanoparticles were studied by DNase I digestion and transfection, and the immune responses elicited in specific pathogen-free (SPF) mice by the pcDNA3.1 (+)-cagW-cS-NPs were evaluated. Apart from that, the protective potential pcDNA3.1 (+)-cagW-cS-NPs was evaluated by challenging with H. pylori. Results The pcDNA3.1 (+)-cagW-cS-NPs comprises cagW gene of H. pylori that is encapsulated in chitosan nanoparticles, produced with good morphology, high stability, a mean diameter of 117.7 nm, and a zeta potential of + 5.64 mV. Moreover, it was confirmed that chitosan encapsulation protects the DNA plasmid from DNase I digestion, and the immunofluorescence assay showed that the cagW gene could express in HDF cells and maintain good bioactivity at the same time. In comparison to the mice immunized with the control plasmid, in vivo immunization revealed that mice immunized with pcDNA3.1 (+)-cagW-NPs showe

关键词： BALB c chitosan nanoparticles DNA vaccine Helicobacter pylori Virulence factor

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Influence of c-O-H Volatiles on Ni, co, and P Partition between Silicate Melt and Liquid Metal Fe Alloy at 4 GPa, 1550°c

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GEOcHEMISTRY INTERNATIONAL 2020年第6期58卷 670-686页

作者： Lukanin, O. A. Tsekhonya, T. I. Koltashev, V. V. Kononkova, N. N. Russian Acad Sci Vernadsky Inst Geochem & Analyt Chem GEOKhI Moscow 119991 Russia Russian Acad Sci Fiber Opt Res Ctr Moscow 119333 Russia

A set of experiments was carried out in the system NaAlSi3O8-FeO-NiO-coO-Sic-NaH(2)PO(4)at 1550 degrees c, 4 GPa, and oxygen fugacity (fO(2)) 0.5-2.9 log. units below the iron-wustite (IW) buffer to estimate how c-O-H components can affect Ni, co, and P partition between silicate melt and a liquid metallic phase at redox conditions under which the metallic phase is segregated into melting products of the early reduced mantles of the Earth and other planetary bodies. It has been established that the Ni, co, and P partition coefficientsD(\M)(met/sil)between silicate melts saturated with carbon and containing dissolved c-O-H volatiles (mainly in the form of OH groups, H(2)and cH4) at relatively oxidized conditions (fO(2)> IW - 1.5) correspond toD(\M)(met/sil)values expected of metal-silicate melt equilibrium in volatile-free systems at analogousP,T,f(O2), andnbo/tparameters. Under more reduced conditions (fO(2)<= IW - 2), the presence of c-O-H volatiles leads to a decrease inD(\M)(met/sil)for Ni and P compared to that in "dry" melts. This difference increases with decreasingfO(2)and reaches similar to 0.5 and more than one order of magnitude for Ni and P, respectively, atfO(2)= IW - 2.9. The effect of volatiles onD(co)(met/sil)is much weaker, and hence, a decrease infO(2)leads to thatD(Ni)(met/sil)andD(co)(met/sil)converge. The Raman spectra of the experimental glasses and their SIMS analyses for hydrogen show that water content (OH + H2O) in the melts decreases with decreasingfO(2), whereas the contents of cH(4)and complexes with c-H bonds significantly increases. The likely reasons for the decrease inD(\M)(met/sil)under strongly reduced conditions may be changes in the structure of the silicate melts and the origin of complex compounds of siderophile elements with volatiles in these melts.

关键词： experiment oxygen fugacity c Ni co P silicate melt siderophile elements silicate-metal partition

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Modeling the Failure Time and Residual Strength of c/Sic composites under Stress-Oxidation Environment

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TRANSAcTIONS OF THE INDIAN cERAMIc SOcIETY 2020年第4期79卷 212-220页

作者： chen, Peng Niu, Xuming chen, Xihui Sun, Zhigang Zou, Pengjian Song, Yingdong Nanjing Univ Aeronaut & Astronaut Coll Energy & Power Engn Jiangsu Prov Key Lab Aerosp Power Syst Nanjing 210016 Peoples R China Sichuan Aerosp Syst Engn Inst Chengdu 610100 Peoples R China Minist Ind & Informat Technol Key Lab Aeroengine Thermal Environm & Struct Nanjing 210016 Peoples R China Nanjing Univ Aeronaut & Astronaut State Key Lab Mech & Control Mech Struct Nanjing 210016 Peoples R China

Based on the oxidation kinetics of c/Sic composites at 900o-1200oc in stress-oxidation environment, a non-uniform model of oxidation has been suggested in this paper. combined with fiber notch model, curtin's strength model and BHE model, the non-uniform model is able to predict the failure time and residual strength of c/Sic composites accurately. Besides, the initial defects of the model (matrix coating crack and open porosity), the effects of coating were taken into account, and the fiber strength and broken ratio were analyzed. Furthermore, the effects of oxidation time, stress, temperature, Si c coating thickness and volume fraction of fiber on the failure time and residual strength were discussed, and the predicted results showed a good consistency with the experimental data.

关键词： c Si c composites Stress-oxidation Failure time Residual strength Predictive model

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c. elegans ribosomal protein S3 protects against H2O2-induced DNA damage and suppresses spontaneous mutations in yeast

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DNA REPAIR 2022年 117卷 103359页

作者： Elsakrmy, Noha Aouida, Mustapha Hindi, Nagham Moovarkumudalvan, Balasubramanian Mohanty, Ashima Ali, Reem Ramotar, Dindial Hamad Bin Khalifa Univ Qatar Fdn Coll Hlth & Life Sci Div Biol & Biomed Sci POB 34110 Doha Qatar Hamad Bin Khalifa Univ Qatar Fdn Coll Hlth & Life Sci Div Genom & Precis Med POB 34110 Doha Qatar

carcinogenicity and cytotoxicity are severe consequences of DNA damage. Base Excision Repair (BER) is a conserved DNA repair pathway that replaces many damaged bases caused by oxidation. Aberrations in BER are associated with carcinogenesis, neurodegeneration, and aging. The nematode c. elegans is an attractive model system for studying BER. However, in this organism, the complete pathway is not fully delineated. To further explore the BER process in c. elegans, we used affinity tag chromatography and mass spectrometry to identify the interactome of uracil DNA glycosylase-1 (ceUNG-1), an enzyme that acts during the first step of the BER pathway. Our analysis identified that ceUNG-1 is associated with the 40 S ribosomal protein S3 (ceRPS-3), homologs of which have been shown to process 8-oxoguanine and abasic site lesions in other organisms. We report a strong in silico association between ceUNG-1 and ceRPS-3 and confirmed this interaction using the yeast two-hybrid system. Downregulation of the cerps-3 gene reduced the viability of wild-type worms upon exposure to the chemical oxidant hydrogen peroxide. Further analysis shows that cerps-3 knockdown significantly sensitized the AP endonuclease APN-1-deficient strain, apn-1, but to a lesser extent exo-3, to the lethal effects of hydrogen peroxide. A cross-species complementation experiment reveals that the expression of ceRPS-3 rescued the hydrogen peroxide sensitivity, and suppressed the high mutation frequency of the yeast AP endonucleasedeficient strain lacking Apn1 and Apn2. We propose that ceRPS-3 may function as an auxiliary DNA repair enzyme in c. elegans to process oxidative DNA lesions.

关键词： RNAinterference Yeasttwo-hybridsystem APendonuclease c elegansmutants 8-oxoguanine OGG1

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Eggshell-membrane-templated synthesis of c, S Doped Mesoporous NiO for methanol oxidation in alkaline solution

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JOURNAL OF APPLIED ELEcTROcHEMISTRY 2020年第8期50卷 821-834页

作者： Gu, Yingying Yu, Zhenzhen Wu, Siqin Gao, Pengyu Hu, Yifen Zhang, chuan Xu, Zhen Li, Jing An, Yarui Univ Shanghai Sci & Technol Coll Sci Shanghai 200093 Peoples R China Univ Shanghai Sci & Technol Ctr Publ Expt Shanghai 200093 Peoples R China

An interwoven hollow fiber structured mesoporous NiO catalyst doped with c, S was fabricated by the vacuum impregnation and thermal decomposition methods using eggshell membrane as template. The structure of the catalyst was characterized by X-ray diffraction, thermo-gravimetric analysis, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and specific surface area test. Under a high vacuum condition, the synthesized NiO material has a better interwoven fiber and mesoporous structure, which effectively increases the specific surface area of the material. c and S were doped into NiO via eggshell membrane pyrolysis, which then formed c-OH and SO42- species on the surface of the material. The electrocatalytic performance of the catalyst for the oxidation of methanol in alkaline solution was studied by cyclic voltammetry and chronoamperometry. The c, S doped mesoporous NiO material exhibits much higher catalytic efficiency and anti-poisoning ability than that of NiO nanoparticles due to the synergistic catalysis of NiO and doping c-OH and SO42- species. Graphic abstract

关键词： Eggshell membrane High vacuum c S doped NiO material

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