检索结果-南通市图书馆

Enhanced preparation of dendritic metallic vanadium in recyclable NaCl-KCl-VCl_(2) molten salt by V_(2)CO electrolysis

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第8期43卷 3961-3973页

作者： Jia-Liang An Ming-Yong Wang Yong-zheng Jia Jin-tao Zhang Bao-Yan Feng Shu-Qiang Jiao State Key Laboratory of Advanced Metallurgy University of Science and Technology BeijingBeijing 100083China College of Material Science and Engineering Hebei Province Laboratory of Inorganic Nonmetallic MaterialsNorth China University of Science and TechnologyTangshan 063210China

A promising method for the preparation of pure metallic vanadium via V_(2)CO anode electrolysis was proposed and *** simple and controllable synthesis of a molten chloride salt containing VCl_(2) by an insitu reaction between VCl_(3) and metallic vanadium was verified through thermodynamic analysis and ***-KCl-VCl_(2) molten salt exhibited excellent recycling performance and could be repetitively used to prepare metallic vanadium by V_(2)CO *** V^(2+) ions remained in the molten salt after *** electrolysis conditions,such as the cathode diameter,current density,V^(2+) ion concentration,and temperature,were optimised to maximise the current *** was also simulated to reveal the regulatory *** highest current efficiency was 85%.The purity of metallic vanadium was up to 99.8%.In this study,an easy and efficient preparation of pure metallic vanadium was achieved.

关键词： V_(2)CO Metallic vanadium Current efficiency Molten salt electrolysis

Defect-manipulated magnetoresistance and above-room-temperature ferromagnetism in two-dimensional BaNi_(2)V_(2)O_(8)

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第3期35卷 523-527页

作者： Pengfei Tan Chuanhui Zhu Jinjin Yang Shuang Zhao tao Xia Mei-Huan Zhao tao Han zheng Deng Man-Rong Li Key Laboratory of Bioinorganic and Synthetic Chemistry of Ministry of Education School of ChemistrySun Yat-sen UniversityGuangzhou 510006China School of Science and Engineering The Chinese University of Hong KongShenzhen 518172China Institute of Physics Chinese Academy of SciencesBeijing 100190China School of Science Hainan UniversityHaikou 570228China

The intricate correlation between multiple degrees of freedom and physical properties is a fascinating area in solid state chemistry and condensed matter ***,we report a quantum-magnetic system BaNi_(2)V_(2)O_(8)(BNVO),in which the spin correlation was modulated by unusual oxidation state,leading to different magnetic *** BNVO was modified with topochemical reduction(TR)to yield TR-BNVO with partially reduced valance state of Ni^(+)in the two-dimensional NiO_(6)-honeycomb ***,the antiferromagnetic order is suppressed by the introduction of locally interposed Ni^(+)and oxygen vacancies,resulting in a ferromagnetic ground state with the transition temperature up to 710 K.A positive magnetoresistance(7.5%)was observed in the TR-BNVO at 40 K under 7 *** findings show that topological reduction is a powerful approach to engineer low-dimensional materials and accelerate the discovery of new quantum magnetism.

关键词： Layered honeycomb oxide Topochemical reduction Oxygen vacancies Ferromagnetism Magnetoresistance

Comparison of bulk snow density measurements using different methods

在线全文

学校读者我要写书评

暂无评论

Advances in Climate Change Research 2024年第4期15卷 658-668页

作者： Hang SU Xin-Yue ZHONG Bin CAO Yuan-tao HU Lei zheng Tingjun ZHANG State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072China Key Laboratory of Remote Sensing of Gansu Province Heihe Remote Sensing Experimental Research StationNorthwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Key Laboratory of Tibetan Plateau Earth System Environment and ResourcesNational Tibetan Plateau Data CenterInstitute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Climate Centre of Shaanxi Province Xi'an71000China School of Geospatial Engineering and Science Sun Yat-sen University and Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Key Laboratory of Westem China's Environmental Systems(Ministry of Education).College of Earth and Environmental Sciences Lanzhou Universiny Lanzhou 730000China

Snow density is one of the basic properties used to describe snow cover characteristics,and it is critical for remote sensing retrieval,water resources assessment and modeling *** are many instruments available to measure snow density in ***,there are mea-surement errors of snow density for bulk and layers or gravimetric and electronic instruments,which may affect the accuracy of remote sensing retrieval and model *** in China,due to the noticeable heterogeneity of snowpacks,it is necessary to evaluate in detail the performance and applicability of snow density instruments in different snowpack *** study evaluated the performance of different snow density instruments:the Federal Sampler,the model VS-43 snow density cylinder(VS-43),the wedge snow density cutter(WC1000 and WC25O),and the Snow *** average bulk snow density of all instrument measurements was set as the reference value for *** results showed that as compared with the reference,the VS-43 cylinder presented the best performance for bulk snow density measurement in the measured range with the lowest RMSE(11 kg m-3),BIAS(3 kg m-3),and MRE(1.6%).For layer observation,bulk snow density was overestimated by 8.1%with WC1000 and underestimated by 11.4%with Snow Fork which was the worst performance compared with the reference value,and there were greater measurement errors of snow density in the depth hoar than other snow *** with grassland,the uncertainty of snow density measurements was slightly lower in ***,the Federal Sampler and VS-43 cylinder are more suitable for bulk snow density measurement in deep snowpack regions across China,and it is recommended to use WC1000,WC250 and Snow Fork to measure the snow density of snow layers in the snow stratigraphy.

关键词： Snowdensity Measurement Uncertainty comparison

Passivation remediation of weakly alkaline Cd-contaminated soils using combined treatments of biochar and sepiolite

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Ecological Processes 2024年第1期13卷 40-52页

作者： Yuxin Zhang Shan Gao Hongtao Jia tao Sun Shunan zheng Shihang Wu Yuebing Sun Key Laboratory of Original AgroEnvironmental Pollution Prevention and Control Ministry of Agriculture and Rural Affairs (MARA)/Tianjin Key Laboratory of Agro-Environment and Agro-Product Safety Agro–Environmental Protection InstituteMARA College of Resources and Environment Sciences Xinjiang Agricultural University Rural Energy and Environment Agency Ministry of Agriculture and Rural Affairs

Background Cadmium(Cd) pollution in agricultural soils has become a priority environmental concern globally. A reasonable application of passivators is critical to address the problem. In this study, we examined the remediation effects of rice husk biochar(r BC) and sepiolite(Sep) as single and combined(r BC + Sep) treatments on Cd pollution in a weakly alkaline soil using three maize cultivars(Liyu 16, zhengdan 958, and Sanbei 218) as test crops. We also explained the mechanisms involved in the remediation *** The pseudo-second-order kinetic equation and Langmuir model could well describe the adsorption process of r BC + Sep for Cd2+. Compared with the control treatment(CK), soil available Cd concentration decreased by 29.51–36.34% under r BC + Sep treatment(pzhengdan 958, and Sanbei 218 decreased by 38.08–47.85%, 37.25–45.61%, and 33.96–46.15%, respectively(pzhengdan 958(0.07–0.13). In addition, r BC +Sep treatment increased soil p H and soil electrical conductivity, but the differences were not significant(p> 0.05).Conclusions The application of 0.2% r BC + 0.5% Sep composite passivation material to weakly alkaline Cd-contaminated soil can effectively reduce the Cd concentration of soil and maize.

关键词： Cd Rice husk biochar Sepiolite Passivation restoration Weakly alkaline soil Maize

Comparative analyses of mitogenomes in the social bees with insights into evolution of long inverted repeats in the Meliponini

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Zoological Research 2024年第1期45卷 160-175页

作者： Yu-Ran Li zheng-Wei Wang Richard T.Corlett wen-Bin Yu Yunnan Key Laboratory for the Conservation of Tropical Rainforests and Asian Elephants&Center for Integrative Conservation Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnan 666303China Southeast Asia Biodiversity Research Institute Chinese Academy of SciencesMenglaYunnan 666303China University of Chinese Academy of Sciences Shijingshan DistrictBeijing 100049China

The insect mitogenome is typically a compact circular molecule with highly conserved gene ***,mitogenome structural variations have been reported in specific taxa,and gene rearrangements,usually the tRNAs,occur in different *** synapomorphies of mitogenome organizations can provide information for phylogenetic inferences,comparative analyses of mitogenomes have been given increasing ***,most studies use a very few species to represent the whole genus,tribe,family,or even order,overlooking potential variations at lower taxonomic levels,which might lead to some incorrect *** provide new insights into mitogenome organizations and their implications for phylogenetic inference,this study conducted comparative analyses for mitogenomes of three social bee tribes(Meliponini,Bombini,and Apini)based on the phylogenetic framework with denser taxonomic sampling at the species and population *** analyses revealed that mitogenomes of Apini and Bombini are the typical type,while those of Meliponini show diverse variations in mitogenome sizes and *** inverted repeats(IRs)cause significant gene rearrangements of protein coding genes(PCGs)and rRNAs in Indo-Malay/Australian stingless bee *** evolution analyses showed that the lineage with IRs have lower dN/dS ratios for PCGs than lineages without IRs,indicating potential effects of IRs on the evolution of mitochondrial *** finding of IRs and different patterns of gene rearrangements suggested that Meliponini is a hotspot in mitogenome *** conserved PCGs and rRNAs whose rearrangements were found only in the mentioned lineages within Meliponini,tRNA rearrangements are common across all three tribes of social bees,and are significant even at the species level,indicating that comprehensive sampling is needed to fully understand the patterns of tRNA rearrangements,and their implications for phylogenetic inference.

关键词： Social bees Phylogeny Mitogenome structure Gene rearrangement Inverted repeats

Production of Functional Materials Derived from Regenerated Silk Fibroin by Utilizing 3D Printing and Biomimetic Enzyme-induced Mineralization

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2024年第3期42卷 299-310,I0005页

作者： Ni Chen Fei-Yu Luo Gong-wen Yang Jin-Rong Yao Xin Chen zheng-Zhong Shao State Key Laboratory of Molecular Engineering of Polymers Laboratory of Advanced Materials and Department of Macromolecular ScienceFudan UniversityShanghai 200433China

Critical-sized bone defects, commonly encountered in clinical orthopedic surgery, present a significant challenge. One of the promising solutions is to prepare synthetic bone substitute materials with precise structural control, mechanical compatibility, and enhanced osteogenic induction performance, nevertheless the successful preparation of such materials remains difficult. In this study, a two-step technique,integrating an extrusion-based printing process with biomimetic mineralization induced by alkaline phosphatase(ALP), was developed. Initially,a pre-cured hydrogel of regenerated silk fibroin(RSF) with a small quantity of hydroxypropyl cellulose(HPC) and ALP was prepared through heating the mixed aqueous solution. This pre-cured hydrogel demonstrated thixotropic property and could be directly extruded into predetermined structures through a 3D-printer. Subsequently, the 3D-printed RSF-based materials with ALP underwent biomimetic in situ mineralization in calcium glycerophosphate(Ca-GP) mineralizing solution, utilizing the polymer chains of RSF as templates and ALP as a trigger for cleaving phosphate bonds of Ca-GP. The resulting 3D-printed RSF-mineral composites including hydrogel and sponge possessed adjustable compression modulus of megapascal grade and variable hydroxyapatite content, which could be controlled by manipulating the duration of the mineralization ***, these 3D-printed RSF-mineral composites demonstrated non-cytotoxicity towards rat bone marrow mesenchymal stem cells. Therefore, they may hold great potential for applications involving the replacement of tissues characterized by osteoinductivity and intricate structures.

关键词： Silk protein Alkaline phosphatase Extrusion-based printing Biomineralization

Facile surface regulation for highly efficient and thermally stable perovskite solar cells via chlormequat chloride

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第10期35卷 517-523页

作者： Bo Yang Pu-An Lin Tingwei Zhou Xiaojia zheng Bing Cai wen-Hua Zhang Institute of Chemical Materials China Academy of Engineering PhysicsMianyang 621900China School of Physical Science and Technology Southwest UniversityChongqing 400715China Yunnan Key Laboratory of Carbon Neutrality and Green Low-carbon Technologies School of Materials and EnergyYunnan UniversityKunming 650000China

Defects at the surface and grain boundaries of the perovskite films are extremely detrimental to both the efficiency and stability of perovskite solar cells(PSCs).Herein,a simple and stable quaternary ammonium halide,named chlormequat chloride(i.e.,chlorinated choline chloride,CCC),is introduced to regulate the upper surface chemical environment of perovskite *** anion(Cl^(-))and cation[ClCH_(2)CH_(2)N(CH_(3))_(3)]+in CCC could effectively self-search and passivate positively and negatively charged ionic defects in per ovskites,respectively,which contributes to inhibited nonradiative recombination and reduced energy los in *** a result,the champion power conversion efficiency(PCE)of PSCs can be significantly enhanced from 22.82%to 24.07%.Moreover,the unencapsulated device with CCC modification retains 92.0%of it original PCE even subject to thermal aging at 85℃ for 2496 *** work provides guidance for the ratio nal design of functional molecules as defect passivators in PSCs,which is beneficial for the improvement in both device performance and stability.

关键词： Perovskite solarcells Quaternary ammonium halide Chlormequat chloride Surface modulation Thermal stability

One-step conversion of methane and formaldehyde to ethanol over SA-FLP dual-active-site catalysts: A DFT study

在线全文

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第4期35卷 544-548页

作者： tao Ban Xi-Yang Yu Hai-Kuo Tian zheng-Qing Huang Chun-Ran Chang Shaanxi Key Laboratory of Energy Chemical Process Intensification School of Chemical Engineering and TechnologyXi'an Jiaotong UniversityXi'an 710049China Shaanxi Key Laboratory of Low Metamorphic Coal Clean Utilization School of Chemistry and Chemical EngineeringYulin UniversityYulin 719000China

One-step conversion of methane and formaldehyde into ethanol is a 100% atom-efficient process for carbon resources utilization and environment protection but still faces eminent challenges due to the lacking of efficient catalysts. Therefore, developing active and stable catalysts is crucial for the co-conversion of methane and formaldehyde. Herein, twelve kinds of “Single-Atom”-“Frustrated Lewis Pair”(SA-FLP)dual-active-site catalysts are designed for the direct conversion of methane and formaldehyde to ethanol based on density functional theory(DFT) calculations and microkinetic simulations. The results show that the SA-FLP dual active sites can simultaneously activate methane at the SA site and activate formaldehyde at the FLP site. Among the twelve designed SA-FLP catalysts, Fe1-FLP shows the best performance in the co-conversion of methane and formaldehyde to ethanol with the rate-determining barrier of 1.15 e *** is proved as the main product with the turnover frequency of 1.32 × 10^(-4)s^(-1)at 573 K and 3 *** work provides a universal strategy to design dual active sites on metal oxide materials and offers new insights into the effective conversion of methane and formaldehyde to desired C_(2) chemicals.

关键词： Single-atom Frustrated Lewis pairs Methane conversion Dual active sites Ethanol synthesis

Spatiotemporal Distributions of Bacterioplankton Communities in the Qiantang River(Hangzhou Section),China

在线全文

学校读者我要写书评

暂无评论

Journal of Ocean University of China 2024年第4期23卷 1102-1114页

作者： XU Jiaojiao ZHAO Li LUKWAMBE Betina NICHOLAUS Regan ZHU Jinyong YANG wen zheng Zhongming School of Marine Sciences Ningbo UniversityNingbo 315211China School of Aquatic Sciences and Fisheries Technology University of Dar es SalaamDar es SalaamTanzania Department of Natural Sciences Mbeya University of Science and TechnologyMbeyaTanzania

The spatial and temporal distribution of bacterioplankton communities plays a vital role in understanding the ecological dynamics and health of aquatic *** this study,we conducted a comprehensive investigation of the bacterioplankton communities in the Qiantang River(Hangzhou section).Water samples were collected quarterly from seven sites over a one-year *** and chemical parameters,including dissolved oxygen(DO),water temperature(WT),chemical oxygen demand(COD),nitrite(NO_(2)^(-)),active phosphate(PO_(4)^(3-))and other indices were *** this study,theαdiversity,βdiversity and abundance differences of bacterial communities were investigated using 16S rRNA high-throughput sequencing *** spatial and temporal distribution characteristics and main driving factors of the bacterioplankton community structure and diversity were *** results showed that a total of 57 phyla were detected in the bacterioplankton community,among which Proteobacteria and Actinomycetes were the two dominant groups with the highest relative *** results of PCoA based on Bray-Curtis distance showed that the sampling season had a slightly greater effect on the changes in bacterioplankton community structure in the Qiantang *** and partial Mantel test showed that environmental variables(Mantel r=0.6739,P<0.0001;partial Mantel r=0.507,P=0.0001)were more important than geographical distance(Mantel r=0.5322,P<0.001;partial Mantel r=0.1563,P=0.001).The distance attenuation model showed that there was significant distance attenuation in all four seasons,and the maximum limit of bacterial community diffusion was found in *** analysis showed that nine environmental factors,including COD,WT and DO,significantly affected community distribution(P<0.05).This study provides valuable insights into the spatial and temporal distribution characteristics of bacterioplankton communities,shedding light on their ecological roles in the Qiantang R

关键词： Qiantang River bacterioplankton community spatial and temporal distribution 16S rRNA range attenuation