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Sulphur-template method for facile manufacturing porous silicon electrodes with enhanced electrochemical performance

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Chinese Chemical Letters 2024年第8期35卷 433-436页

作者： Peng Zhou Ziang jiang Yang Li Peng Xiao Feixiang wu Powder Metallurgy Research Institute School of Metallurgy and EnvironmentCentral South UniversityChangsha 410083China

Sulphur(S)-template method based on conventional slurry-casting method has been developed to pro-duce porous silicon(Si)*** facile fabrication technology is suitable for current production line and expected to be widely applied to various electrode materials under large volume change during ***,S particles as template agent are mixed with active material Si,carbon conductor and binder forming uniform *** casting and drying,the electrodes are immersed in carbon disul-fide solution to remove S particles rapidly,generating pores in-situ at the original position of S *** analysis shows that the pores inside electrodes are able to shorten lithium ion diffusion paths,reduce normal expansion rate and decrease formation of cracks in the Si electrode(2 mg_(Si)/cm^(2)),demonstrating a reversible capacity of 951 mAh/g at 0.5 A/g after 100 cycles(with a capacity retention of 99.5%)and a capacity of-826 mAh/g at 2 A/g.

关键词： Sulphur-template Porous electrodes Silicon anodes Low volume expansion Lithium-ion batteries

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Thermal stability of permafrost under U-shaped crushed rock embankment of the Qinghai-Tibet Railway

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Advances in Climate Change Research 2024年第1期15卷 158-169页

作者： Kun-Ming XU Guan-Li jiang Ji CHEN Qing-Bai wu State Key Laboratory of Frozen Soil Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China University of Chinese Academy of Sciences Beijing 100049China Beiluhe Observation Station of Frozen Soil Environment and Engineering Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou730000China

The U-shaped crushed rock embankment(UCRE),of which widely utilized in the permafrost regions along the Qinghai-Tibet Railway,has the capability to rapidly reduce the ground temperature of the underlying ***,there remains uncertainty regarding the adaptation of UCRE to climate change and its long-term cooling *** study focuses on nine UCRE monitoring sites along the Qinghai-Tibet Railway to analyze the dynamic variations of the ground temperature underlying permafrost from 2006 to *** efficiency of UCRE in stabilizing permafrost temperature in different permafrost zones is evaluated by considering the permafrost table,ground temperature,and MAGT,as well as the temperature difference between the top and bottom of the crushed rock layer and the ground temperature variation index(GTVI).The results show that UCRE is suitable for application in extremely unstable warm permafrost regions where the MAGT is higher than-0.5℃.Moreover,UCRE effectively diminishes the disparity in permafrost thermal stability between the sunny and shaded shoulders of the *** short-term and long-term effect of cooling permafrost is experiencing a change related with permafrost ***,in stable cold permafrost regions with MAGT lower than-1.5℃,the long-term cooling effect of UCRE on permafrost seems to gradually di-minishes,but UCRE continues to fulfill the role of stabilizing the underlying permafrost thermal state over the *** results show that UCRE can quickly restore and stabilize the thermal state of permafrost in the early stages of construction,and adapt to the influence of future climate *** findings provide important guidance for understanding the variations of permafrost thermal stability beneath the embankment in permafrost regions,as well as for improving the embankment stability and operational safety of the Qinghai-Tibet Railway.

关键词： Qinghai-Tibet Railway U-shaped crushed rock embankment Climate change Permafrost zone Ground temperature variation index Long-term coolingrole

SiC Double Trench MOSFET with Split Gate and Integrated Schottky Barrier Diode for Ultra-low Power Loss and Improved Short-Circuit Capability

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Chinese Journal of Electronics 2024年第5期33卷 1127-1136页

作者： Jinping ZHANG Qinglin wu Zixun CHEN hua ZOU Bo ZHANG State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic Science and Technology of China

A silicon carbide（SiC） double trench metal-oxide-semiconductor field effect transistor（DTMOS） with split gate（SG） and integrated Schottky barrier diode（SBD） is proposed for the first *** proposed device features two enhanced deep trenches in the surface,in which a source-connected SG with a thicker dielectric layer is located at the bottom of the deep gate trench and an integrated SBD is located at the sidewall of the deep source trench（DST）.Combined with shielding effect provided by the P+shield layer under the DST and integrated SBD,the proposed structure not only reduces the reverse transfer capacitance(Crss) and gate-drain charge(Qgd) but also restrains the saturation drain current(Id,sat) and improves the diode performance of the *** analysis results show that compared with the Con-DTMOS and Con-DTMOS with external SBD diode,the turn-on loss(Eon) and turn-off loss(Eoff) for the proposed device are reduced by 56.4%/70.4% and 56.6%/69.9%,***,the Id,satat the Vgsof 18 V for the proposed device is reduced by 74.4% and the short-circuit withstand time(tSC) is improved by about 7.5 *** a result,an ultra-low power loss and improved short-circuit capability is obtained for the proposed device.

关键词： Performance evaluation Schottky diodes Time-frequency analysis Silicon carbide Simulation Schottky barriers Low power electronics Metal-oxide-semiconductor field effect transistor (MOSFET) Specific on resistance Reverse transfer capacitance High frequency figure of merit Forward conduction voltage drop Turn-on loss Turn-off loss Saturated drain current Short-circuit withstand time

One-Pot Stereoselective Synthesis of Different Fused Multicyclic Iminosugars Based on the Iminium-lon Intermediate

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Chinese Journal of Chemistry 2024年第2期42卷 142-150页

作者： Song Xie Jilai wu Likai Zhou Chao Wei Xiaoliu Li hua Chen Key Laboratoryof Chemical Biology of Hebei Province College of Chemistry and Material ScienceHebei UniversityBaodingHebei 071002China College of Chemistry and Chemical Engineering Xingtai UniversityXingtaiHebei 054001China

Different novel fused multicyclic iminosugars were synthesized from D-ribose tosylate,aniline and vinyl ethyl ether by one-pot three-component stereoselective[4+2]reaction at different *** iminium-ion is the key intermediate for the *** a result,several complex fused iminosugars 3a were obtained by aza-Diels-Alder mechanism at 60℃,while a series of aza-C-glycosides 5a were prepared by Mannich reaction at room temperature accompanied by another tetrahydroquinoline-fused iminosugars 4a(tricyclic derivatives)through aza-Diels-Alder *** strategy will help to construct structurally diverse and bioactive iminosugar analogues.

关键词： Fused multicyclic iminosugar Aza-Diels-Alder cycloaddition Mannich reaction Tetrahydroquinoline Multicomponent reactions Enantioselectivity Cyclization

Probabilistic back-analysis of rainfall-induced landslides for slope reliability prediction with multi-source information

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第9期16卷 3575-3594页

作者： Shui-hua jiang Hong-Hu Jie Jiawei Xie Jinsong huang Chuang-Bing Zhou School of Infrastructure Engineering Nanchang UniversityXuefu Road 999Nanchang330031China Discipline of Civil Surveying and Environmental EngineeringFaculty of Engineering and Built EnvironmentThe University of NewcastleCallaghanNSW2308Australia

Probabilistic back-analysis is an important means to infer the statistics of uncertain soil parameters,making the slope reliability assessment closer to the engineering ***,multi-source information(including test data,monitored data,field observation and slope survival records)is rarely used in current probabilistic *** the probabilistic back-analysis of spatially varying soil parameters and slope reliability prediction under rainfalls by integrating multi-source information is a challenging task since thousands of random variables and high-dimensional likelihood function are usually *** this paper,a framework by integrating a modified Bayesian Updating with Subset simulation(mBUS)method with adaptive Conditional Sampling(aCS)algorithm is established for the probabilistic back-analysis of spatially varying soil parameters and slope reliability *** this framework,the high-dimensional probabilistic back-analysis problem can be easily tackled,and the multi-source information(*** pressure heads and slope survival records)can be fully used in the back-analysis.A real Taoyuan landslide case in Taiwan,China is investigated to illustrate the effectiveness and performance of the established *** findings show that the posterior knowledge of soil parameters obtained from the established framework is in good agreement with the field ***,the updated knowledge of soil parameters can be utilized to reliably predict the occurrence probability of a landslide caused by the heavy rainfall event on September 12,2004 or forecast the potential landslides under future rainfalls in the Fuhsing District of Taoyuan City,Taiwan,China.

关键词： Rainfall-induced landslide Spatial variability Probabilistic back-analysis Slope reliability analysis Bayesian updating

Regulating the key performance parameters for Hg-based IR NLO chalcogenides via bandgap engineering strategy

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Chinese Chemical Letters 2024年第10期35卷 490-494页

作者： A-Yang Wang Sheng-hua Zhou Mao-Yin Ran Xin-Tao wu hua Lin Qi-Long Zhu State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of Sciences(CAS)Fuzhou 350002China Fujian Science&Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou 350108China College of Chemistry Fuzhou UniversityFuzhou 350108China University of Chinese Academy of Sciences Bejing 100049China

Recently,non-centrosymmetric(NCS)Hg-based chalcogenides have garnered significant interest due to their strong second-harmonic-generation intensities(deff),making them attractive candidates for infrared nonlinear optical(IR-NLO)***,achieving both wide band gaps(Eg)and large phasematched deffsimultaneously in these materials remains a challenge due to their inherent constraints on each *** this research,we have successfully obtained two quaternary NCS Hg-based chalcogenides,Rb2HgGe_(3)S_(8)and Cs_(2)HgGe_(3)S_(8),by implementing a bandgap engineering strategy that involves alkali metal introduction and Hg/Ge ratio *** compounds consist of 2D[Hg Ge_(3)S_(8)]_(2)–anionic layers made of 1D[HgGeS_(6)]^(6–)chains and dimeric[Ge_(2)S_(6)]_(4–)polyhedra arranged alternately,and the charge-balanced Rb+/Cs+cations located between these ***,Rb_(2)HgGe_(3)S_(8)and Cs_(2)HgGe_(3)S_(8)exhibit overall properties required for promising IR-NLO materials,including sufficient PM deff(0.55–0.70×AgGaS_(2)@20_(5)0 nm),large Eg(3.27–3.41 e V),giant laser-induced damage thresholds(17.4–19.7×AgGaS_(2)@1064 nm),broad optical transmission intervals(0.32–17.5μm),and suitable theoretical birefringence(0.069–0.086@2050 nm).Furthermore,in-depth theoretical analysis reveals that the exceptional IRNLO performance is attributed to the synergy effects of distorted[HgS_(4)]and[GeS_(4)]*** study provides a useful strategy for enhancing the Eg and advancing Hg-based IR-NLO materials,which is expected to extended and implemented in other chalcogenide systems.

关键词： Hg-based chalcogenides IR nonlinear material Structure-activity relationship Wide energy gap Bandgap engineering strategy

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Electrocatalytic performance of CNTs/graphene composited rare earth phthalocyanines(M=La,Y,Yb,Sc)

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Journal of Rare Earths 2024年第2期42卷 323-333,I0004页

作者： Tingting jiang Caixia Ou Luyi Wang Jun Chen Sydorov Dmytro Qian Zhang Jintian Luo hua Wang jiangxi Key Laboratory of Power Batteries and Materials Faculty of Materials Metallurgy and ChemistryJiangxi University of Science and TechnologyGanzhou341000China Joint Department of Electrochemical Energy Systems Institute of Bioorganic Chemistry and PetrochemistryNational Academy of Sciences of Ukraine38A VernadskyAveKiev03142Ukraine Guangdong Jiana Energy Technology Co. Ltd.Qingyuan511500China

In this study,a class of rare earth composite sandwich phthalocyanines(MPcs,M=La,Y,Yb,Sc) were prepared and compounded with graphene and carbon nanotubes to obtain MPc/Gr and MPc/CNTs *** electrocatalytic behaviors of MPc/Gr and MPc/CNTs electrodes were further *** results show that the central rare earth metal has a large influence on the electrocatalytic *** the MPcs/Gr samples,ScPc with the smallest ionic radius and molecular size can be more uniformly dispersed in graphene,and the hydrogen precipitation overpotential of ScPc/Gr electrode is514 mV,corresponding to a Tafel slope of 148 mV/dec,with better electrocatalytic performance than other rare earth metal *** for the MPc/CNTs composites,LaPc,which has the largest ionic radius and molecular size,is more uniformly dispersed on the surface of CNTs,so that the LaPc/CNT electrode exhibits the best LSV performance with the smallest corresponding Tafel slope(176 mV/dec).The main reason is the different binding modes of MPcs molecules in Gr and *** rare earth phthalocyanine is combined with layered graphene,the smallest size of rare earth phthalocyanine(ScPc)is more easily embedded in the graphene layer,resulting in better homogeneity of the composite,larger effective contact area and better electrocatalytic *** contrast,when rare earth phthalocyanine is bound to carbon nanotubes in a tubular structure,it is mainly bound by attaching to the surface or being entangled by the carbon *** this case,the rare-earth phthalocyanine molecules(LaPc)with larger layer spacing can provide more contact area with CNTs,forming a more uniform and effective composite,which eventually provides more active sites and better electrocatalytic performance.

关键词： Electrocatalysis Rare earth phthalocyanines Graphene(Gr) Carbon nanotubes(CNTs) Composite

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Enhancing growth, liver health, and bile acid metabolism of tilapia(Oreochromis niloticus) through combined cholesterol and bile acid supplementation in plant-based diets

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Animal Nutrition 2024年第2期17卷 335-346页

作者： Jiayuan jiang Xing Lu Lixue Dong Juan Tian Jianmin Zhang Zhongbao Guo Yongju Luo Zongbin Cui hua Wen Ming jiang College of Fisheries and Life Science Shanghai Ocean University Yangtze River Fisheries Research Institute Chinese Academy of Fishery Sciences Guangdong Provincial Key Laboratory of Microbial Culture Collection and Application State Key Laboratory of Applied Microbiology Southern ChinaInstitute of MicrobiologyGuangdong Academy of Sciences Guangxi Institute of Fisheries

The present study aimed to compare the nutritional effects of cholesterol, bile acids, and combination of cholesterol with bile acids in plant-based diets on juvenile genetically improved farmed tilapia(GIFT;Oreochromis niloticus). The isonitrogenous(321 g/kg crude protein) and isolipidic(76 g/kg crude fat) diets(Con diet) were based on plant protein sources, which included corn gluten meal, soybean meal, cottonseed meal and rapeseed meal. The Con diet was supplemented with 12 g/kg cholesterol(CHO diet), 0.2 g/kg bile acids(BAs diet), a combination of 12 g/kg cholesterol and 0.2 g/kg bile acids(CHO-BAs diet),respectively. Each diet was fed to three tanks in an indoor recirculating aquaculture system for 9 *** showed that compared to the Con group, fish had a higher weight gain rate, hepatosomatic index,and a lower feed conversion ratio in the CHO-BAs group. The highest levels of whole-fish fat and ash were found in the Con group. Serum parameters, including activities of alanine aminotransferase(ALT) and aspartate transaminase(AST), along with levels of glucose(GLU) and triglyceride(TG) except for total cholesterol(TCHO), were lower in the CHO, BAs, and CHO-BAs groups than those in the Con group(P <0.001). Histological examination revealed that fish in the Con group exhibited severe hepatocyte vacuolization and diminished hepatocyte proliferation. Gene expression analysis indicated that the transcriptional levels of bile acid metabolism-related genes(including fxr, fgf19, bsep) were up-regulated in the CHO-BAs group(P < 0.05), whereas cholesterol metabolism-related genes(acly and hmgcr) were downregulated in both CHO and CHO-BAs groups(P < 0.001). Moreover, UPLC-MS/MS analysis revealed that the higher taurine-conjugated bile acids(T-BAs), followed by free bile acids(Free-BAs) and glycine(G-BAs)were determined in tilapia bile. Among these, taurochenodeoxycholic bile acid was the predominant bile acid. Dietary bile acids supplementation also increased the pr

关键词： Bile acid metabolism Tilapia Plant-based feed Cholesterol Liver health

Effect of Room Temperature Ultrasonic Vibration Compression on the Microstructure Evolution and Mechanical Properties of AZ91 Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第7期37卷 1135-1146页

作者： Ziyue Xu huan Liu Luyao Li Chao Sun Xi Tan Baishan Chen Qiangsheng Dong Yuna wu Jinghua jiang jiang Ma College of Materials Science and Engineering Hohai UniversityNanjing210000China Suzhou Research Institute of Hohai University Suzhou215000China Shenzhen Key Laboratory of High Performance Nontraditional Manufacturing College of Mechatronics and Control EngineeringShenzhen UniversityShenzhen518060China Institute of Medical Devices(Suzhou) Southeast UniversitySuzhou215163China Institute for Advanced Study Central South UniversityChangsha410083China jiangsu Key Laboratory of Advanced Structural Materials and Application Technology Nanjing Institute of TechnologyNanjing211167China

To investigate the potential of direct ultrasonic vibration on improving the performance of magnesium alloys,this study first employed the ultrasonic vibration compression(UVC)on the solid solution treated AZ91 alloy,and explored its microstructure evolution and mechanical properties under *** only two seconds,the UVC alloys showed large deformation strains of 34.8–54.4%,and sudden increase of sample temperature to 243℃.Microstructure characterizations proved that UVC promoted the formation of abundant shear bands,fine grains,and the bimodal distribution of Mg17Al12 precipitates consisting of submicron particles located within the shear bands and nano-sized ones within the *** to the unique microstructure,the micro-hardness(and nano-hardness)value of UVC alloy was increased by 37.7%(35%)when compared with the solution-treated ***,the nano-modulus of the developed AZ91 alloy was also significantly increased to 62 GPa by statistical nanoindentation tests,which could be ascribed to increased Mg_(17)Al_(12) precipitates and decreased c/a value to some *** general,this work provides a new insight into the design and preparation of high-performance magnesium alloys by UVC at room temperature.

关键词： AZ91 alloys Ultrasonic vibration compression Precipitation Shear bands Mechanical properties