检索结果-南通市图书馆

Hydrochemical characteristics and the ecological effect of algal carbonic anhydrase in carbon cycle in the taiyuan section of Fenhe River

中国藻类学会第八次会员大会暨第十六次学术讨论会

作者： hu bianfang,xie shulian school of life science,shanxi university,taiyuan 030006,china

＜正＞The effects of environmental factors on stream macroalgae were investigated using grey correlation-regression *** were collected from July 2004 to April 2005 from Xin’ an Spring,shanxi Province,north *** environmental variables were consisted of water temperature,pH,specific conductance,dissolved oxygen,surface current velocity,maximum depth and ***-two species of stream macroalgae were identified in this *** established a linear regression model in which these environmental factors were included as independent variables,and the number of stream macroalgal species was the dependent *** results of analyses with the regression model confirmed that water temperature,current velocity,and specific conductance were the key factors affecting stream macroalgae.

关键词： environmental factors stream macroalgae grey correlation analysis linear regression analysis china

来源： cnki会议评论

在线全文

cnki会议

学校读者我要写书评

暂无评论

Journal of Oceanology and Limnology 2024年第5期42卷 1507-1524页

作者： Jing YANG Xin LI shulian xie Jia FENG shanxi Key Laboratory of Yuncheng Salt Lake Ecological Protection and Resource Utilization College of Life SciencesYuncheng UniversityYuncheng 044000China school of life science Shanxi UniversityTaiyuan 030006China

Water scarcity and pollution pose a threat to the sustainable development of cities and ***,it is crucial to analyze the hydrochemical characteristics and carbon dynamics of waterdeficient *** the taiyuan section of Fenhe River as the research object,we systematically explored the hydrochemical characteristics of surface water and its evolutionary processes,as well as the ecological effect of algal carbonic anhydrase in carbon cycle using the hydrochemical evolution method and correlation *** ternary diagram demonstrates that the main water chemical type in Fenhe River was SO^(2-)_(4)·Cl^(-)-Na^(+).The Gibbs and end-member diagrams of each ion display that the chemical composition of surface water was mainly controlled by silicate *** chemical ions originated mainly from dissolution of some minerals,such as plagioclase,halite,dolomite,calcite,and *** diatoms had a lower CO_(2)requirement because they exhibited a higher abundance at a lower partial pressure of CO_(2)(p CO_(2)).However,high CO_(2)concentration had a positive effect on cyanobacteria,which reduced the active transport of HCO_(3)^(-),saved the energy needed for this part of active transport,and indirectly improved the overall photosynthetic efficiency of *** anhydrase(CA)activity was significantly negatively correlated with p CO_(2)and positively correlated with HCO_(3)^(-)concentration,indicating that CA in water promoted the conversion of CO_(2)to HCO_(3)^(-).The HCO_(3)^(-)generated from this process continued to participate in the erosion of silicate rocks,sequestering CO_(2)in the form of Ca CO_(3),which has a non-negligible impact on the carbon sink in the Fenhe *** consequences may have important implications for the biogeochemical cycling occurring in urban water.

关键词： hydrochemistry inorganic carbon phytoplankton community carbonic anhydrase Fenhe River

A new species of Discostella guiyangensis ***.(Bacillariophyta,Stephanodiscales)from Guiyang,china:morphology and phylogeny

在线全文

学校读者我要写书评

暂无评论

Journal of Oceanology and Limnology 2024年第4期42卷 1312-1324页

作者： Yandan XIANG Fangru NAN Xudong LIU shulian xie John Patrick KOCIOLEK Qi LIU school of life science Shanxi UniversityTaiyuan 030006China Department of Ecology and Evolutionary Biology and Museum of Natural History University of ColoradoBoulder CO 80309USA

We describe a new species of Discostella from Guiyang based on light and scanning electron microscopic observations,as well as molecular *** species is morphologically distinguished from other species by a relatively smooth and slightly recessed central area with marginal striae of unequal lengths forked near the *** fultoportulae and a single rimoportula are situated between every two costae or on the *** morphological characters and the concatenated data of rbc L and SSU rDNA indicate that Discostella guiyangensis is a unique and new *** to divergence time estimation analysis,Discostella guiyangensis is the oldest species among the Discostella species sequenced *** addition,we complement molecular data of Discostella asterocostata and Discostella stelligera.

关键词： Discostella morphology molecular analysis divergence time estimation new species

Morphology and phylogenetic placement of Mallomonas vietnamica(Synurales,Chrysophyceae)from china

在线全文

学校读者我要写书评

暂无评论

Journal of Oceanology and Limnology 2024年第4期42卷 1325-1335页

作者： Junxue HAO Fangru NAN Junping LÜ Qi LIU Xudong LIU shulian xie Jia FENG school of life science Shanxi UniversityTaiyuan 030006China

The newly described chrysophyte,Mallomonas vietnamica,is reported for the first time in china from specimens collected in Guizhou Province,SW *** morphological characteristics were studied using light and scanning electron *** species was described based on morphological characteristics,including cell size,scale size,dome,V-rib,and ***,molecular sequencing of *** was conducted and a phylogenetic tree was constructed based on concatenated SSU,LSU,and rbc L *** phylogenetic tree led us to suggest raising a new section named Uncatusipedae for this *** study provides new molecular data from the genus Mallomonas and enriches our understanding of the species diversity and geographical distribution of the genus Mallomonas in china.

关键词： Chrysophyta Mallomonas vietnamica phylogenetic study taxonomy

Single and combined effects of secondary polyethylene microplastic on the growth of Pak choi and the soil microbiome composition

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental science & Engineering 2024年第5期18卷 1-12页

作者： Jiamin hu Zhenwen xie Jiane Zuo State Key Joint Laboratory of Environmental Simulation and Pollution Control School of EnvironmentTsinghua UniversityBeijing100084China Tsinghua Shenzhen International Graduate school Tsinghua UniversityShenzhen518055China

It has been confirmed that microplastics(MPs)are present in the *** study simulated secondary PE-MPs via aging and mechanical processes to evaluate their effects on Pak choi(Brassica rapa L.)over 21 *** common pollutants,dichlorodiphenyltrichloroethane(DDT)and naphthalene,were used in the combined toxicity *** results indicated that the growth of Pak choi was significantly inhibited after exposure to secondary PE-MPs,and the combined effects were antagonistic,owing to the adsorption capacity of secondary PE-MPs to DDT and *** stress in Pak choi can be markedly affected,leading to oxidative damage to plant *** moisture content,soil bulk density,soil density,cation exchange capacity(CEC),and FDA hydrolase in the planted soils increased in the treated groups,and the TOC content changed *** also found that the microbial composition of the soil in the DDT and naphthalene groups showed more significant alterations than that in the other *** diversity analysis showed that species diversity increased in the combined groups but indicated a clear downward trend in the single MPs *** study suggests that secondary PE-MPs harm the growth of Pak choi and can change soil properties,revealing the harm to the ecosystem of MPs in the soil.

关键词： Secondary PE-MPs Combined effects Oxidative stress Soil properties Bacterial community

Microstructure and mechanical properties of Ti/Al/Ti clad plates prepared via powder-in-tube method

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第3期31卷 670-687页

作者： Xian-lei hu Qin-cheng xie Yi Yuan Ying Zhi State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819LiaoningChina Suzhou Dongbao Haixing Metal Material Technology Co. Ltd.Suzhou 215600JiangsuChina school of Material science and Engineering Northeastern UniversityShenyang 110819LiaoningChina

The Ti/Al/Ti clad plates exhibit a broad spectrum of potential ***,the conventional techniques of hot-pressing composite and explosive composite are intricate and environmentally hazardous.A novel method was introduced for preparing clad plates,namely,the powder-in-tube *** method involves a combination of cold rolling,annealing at a temperature of 550℃,and double *** morphology of the intermetallic compound layer was analyzed through the utilization of interface stripping test,tensile test,and microscopic *** interface morphology,interface bonding properties,tensile fracture structures,and properties of plates under the first and second rolling were compared,along with the effects of intermetallic compounds on the interface *** results indicate that the powder-in-tube method,when annealed at 550℃,can produce a composite plate featuring a complete and uniform Ti/Al *** obtained plate exhibits a peeling strength of 21.5 N/mm,tensile strength of 424 MPa,and elongation of 11.5%.Furthermore,a systematic analysis was conducted to determine the causes of performance degra-dation observed during annealing at temperatures of 600 and 650℃.

关键词： Powder-in-tube method-Ti/Al/Ti clad plate Annealing Cold rolling-Mechanical property

Allosteric DNAzyme-based encoder for molecular information transfer

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Chemical Letters 2024年第7期35卷 235-241页

作者： Minghao hu Tianci xie Yuqiang hu Longjie Li Ting Wang Tongbo Wu school of Pharmacy Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Department of Oncology Tongji Hospital of Tongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China GI Cancer Research Institute Tongji HospitalHuazhong University of Science and TechnologyWuhan 430030China school of life science and Technology Wuhan Polytechnic UniversityWuhan 430023China State Key Laboratory of Bioelectronics National Demonstration Center for Experimental Biomedical Engineering EducationSchool of Biological Science and Medical EngineeringSoutheast UniversityNanjing 210096China

Dynamic DNA nanotechnology plays a significant role in nanomedicine and information science due to its high programmability based on Watson-Crick base pairing and nanoscale *** DNA machines and networks have been widely used in various fields,including molecular imaging,biosensors,drug delivery,information processing,and logic *** serve as crucial components for information compilation and transfer,allowing the conversion of information from diverse application scenarios into a format recognized and applied by DNA ***,there are only a few encoder designs with DNA ***,the molecular priority encoder is hardly *** this study,we introduce allosteric DNAzyme-based encoders for information *** design of the allosteric domain and the recognition arm allows the input and output to be independent of each other and freely *** pre-packaged mode design achieves uniformity of baseline dynamics and dynamics *** also integrated non-nucleic acid molecules into the encoder through the aptamer design of the allosteric ***,we developed the 2^(n)-n encoder and the EndoⅣ-assisted priority encoder inspired by immunoglobulin's molecular structure and effector *** our knowledge,the proposed encoder is the first enzyme-free DNA encoder with DNA output,and the priority encoder is the first molecular priority encoder in the DNA reaction *** encoders avoid complex operations on a single molecule,and their simple structure facilitates their application in complex DNA circuits and biological scenarios.

关键词： DNAzyme Encoder Nucleic acids DNA circuit DNA strand displacement Dynamic DNA nanotechnology

The microscopic formation mechanism of O+H_(2) products from photodissociation of H_(2)O

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Structural Chemistry 2024年第5期43卷 11-13页

作者： Yubang Li Xixi hu Daiqian xie Kuang Yaming Honors school Jiangsu Key Laboratory of Vehicle Emissions ControlNanjing UniversityNanjing210023China Institute of Theoretical and Computational Chemistry Key Laboratory of Mesoscopic ChemistrySchool of Chemistry and Chemical EngineeringNanjing UniversityNanjing210023China

Photodissociation dynamics of water involving its B electronic states yielding OH(A^(2)Σ+/X^(2)Π)+H(^(2)S)products has been intensively investi-gated by both experimental and theoretical studies[1].Theoretically,the Dobbyn-Knowles potential energy surfaces(DK PESs)[2]based on limited complete active space self-consistent field(CASSCF)points were used in dynamic studies for water photodissociation and O+H_(2)reaction about 20 years ago,but the accuracy is not enough to meet current re-quirements.

关键词： mechanism enough yielding

Pore-pressure and stress-coupled creep behavior in deep coal:Insights from real-time NMR analysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Mining science and Technology 2024年第1期34卷 77-90页

作者： Wenhao Jia Hongwei Zhou Senlin xie Yimeng Wang Xinfeng hu Lei Zhang school of Mechanics and Civil Engineering China University of Mining and Technology-BeijingBeijing 100083China school of Energy and Mining Engineering China University of Mining and Technology-BeijingBeijing 100083China State Key Laboratory of Coal Resources and Safe Mining China University of Mining and Technology-BeijingBeijing 100083China College of Safety and Emergency Management Engineering Taiyuan University of TechnologyTaiyuan 030024China

Understanding the variations in microscopic pore-fracture structures(MPFS) during coal creep under pore pressure and stress coupling is crucial for coal mining and effective gas treatment. In this manuscript, a triaxial creep test on deep coal at various pore pressures using a test system that combines in-situ mechanical loading with real-time nuclear magnetic resonance(NMR) detection was ***-scale quantitative characterization, online real-time detection, and visualization of MPFS during coal creep influenced by pore pressure and stress coupling were performed using NMR and NMR imaging(NMRI) techniques. The results revealed that seepage pores and microfractures(SPM) undergo the most significant changes during coal creep, with creep failure gradually expanding from dense primary pore fractures. Pore pressure presence promotes MPFS development primarily by inhibiting SPM compression and encouraging adsorption pores(AP) to evolve into SPM. Coal enters the accelerated creep stage earlier at lower stress levels, resulting in more pronounced creep deformation. The connection between the micro and macro values was established, demonstrating that increased porosity at different pore pressures leads to a negative exponential decay of the viscosity coefficient. The Newton dashpot in the ideal viscoplastic body and the Burgers model was improved using NMR experimental results, and a creep model that considers pore pressure and stress coupling using variable-order fractional operators was developed. The model’s reasonableness was confirmed using creep experimental data. The damagestate adjustment factors ω and β were identified through a parameter sensitivity analysis to characterize the effect of pore pressure and stress coupling on the creep damage characteristics(size and degree of difficulty) of coal.

关键词： Real-time monitoring Pore pressure-stress coupling Microscopic pore-fracture structure Variable-order fractional creep model Deep coal

Advanced modeling of the absorption enhancement of black carbon particles in chamber experiments by considering the morphology and coating thickness

在线全文

学校读者我要写书评

暂无评论

Frontiers of Environmental science & Engineering 2024年第9期18卷 129-142页

作者： Xiaodong Wei Jianlin hu Chao Liu Xiaodong xie Junjie Yin Song Guo Min hu Jianfei Peng huijun Wang Jiangsu Key Laboratory of Atmospheric Environment Monitoring and Pollution Control Collaborative Innovation Center of Atmospheric Environment and Equipment TechnologySchool of Environmental Science and EngineeringNanjing University of Information Science&TechnologyNanjing 210044China Collaborative Innovation Center on Forecast and Evaluation of Meteorological Disasters Key Laboratory of Meteorological Disaster(Ministry of Education)Nanjing University of Information Science and TechnologyNanjing 210044China Nansen−Zhu International Research Centre Institute of Atmospheric PhysicsChinese Academy of SciencesBeijing 100029China East china Air Traffic Management Bureau CAAC Shanghai 200335China State Key Joint Laboratory of Environmental Simulation and Pollution Control International Joint Laboratory for Regional Pollution Control(IJRC)(Ministry of Education)College of Environmental Sciences and EngineeringPeking UniversityBeijing 100871China Tianjin Key Laboratory of Urban Transport Emission Research&State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control College of Environmental Science and EngineeringNankai UniversityTianjin 300071China

Measurements studies have shown that the absorption of radiation by black carbon(BC)increases as the particles ***,there are significant discrepancies between the measured and modeled absorption enhancement(E_(abs)),largely due to the simplifications used in modeling the mixing states and shape *** took advantage of chamber experiments on BC aging and developed an efficient method to resolve the particle shape based on the relationship between the coating fraction(ΔD_(ve)/D_(ve),0)and fractal dimension(D_(f)),which can also reflect the variations of D_(f)during the whole BC aging *** with externally and partly mixed states(0≤ΔD_(ve)/D_(ve),0≤0.5)can be considered to be uniformly distributed with the D_(f)values of 1.8–2.1,whereas the Df values are constrained in the range 2.2–2.8 for fully mixed states(ΔD_(ve)/D_(ve),0>0.5).The morphological parameters(i.e.,the effective density and the dynamic shape factor)were compared with the measured values to verify the simulated *** simulated mean deviations of morphological parameters were smaller than 8%for the method resolving the particle *** applying a realistic shape and refractive index,the mass absorption cross for fully mixed states can be improved by 11%compared with a simplified core–shell *** on our understanding of the influence of D_(f)andΔD_(ve)/D_(ve),0 on E_(abs),we propose a two-stage calibration equation to correct the E_(abs)values estimated by the core–shell model,which reduces the simulation error in the Mie calculation by 6%–14%.

关键词： Black carbon Mixing states Fractal dimension Dynamic shape factor Absorption enhancement