检索结果-南通市图书馆

Using quantile regression to analyze the stressor–response relationships between nutrient levels and algal biomass in three shallow lakes of the Lake Taihu Basin, China

引用

Chinese Science Bulletin 2014年第28期59卷 3621-3629页

作者： xiaohua chen Xiaoping Li State Key Laboratory of Estuarine and Coastal Research East China Normal University Water Environmental Research Institute Shanghai Academy of Environmental Sciences

Understanding the stressor–response relationship between nutrient levels and algal biomass is a prerequisite for the management of eutrophication in lakes. In this study, a quantile regression(QR) approach was used to interpret the stressor–response relationships between nutrient(e.g., phosphorus, nitrogen) concentrations and algal biomass as measured by chlorophyll-a(Chl-a) levels. QR results indicated that Lake Dianshan and Lake Changdang,which are both heavily eutrophicated, were P-limited *** contrast, Lake Kuilei, which has significantly lower nutrient levels and algal biomass than the other two lakes,was P- and N-limited. Moreover, in Lake Kuilei, N and P levels had significant interaction effects on the algal biomass at the upper quantiles(s [ 0.68). The degree to which the lakes were P-limited increased with rises in the mean total P concentration in the lakes. QR has many advantages over ordinary least squares regression for discriminating limiting factors and, in particular, allows us to estimate changes near the upper extremes of distributions associated with limiting factors. QR is adapted to more specialized risk management problems, such as early warnings of the risk of algal *** probable value-at-risk of harmful algal blooms for Lake Kuilei, Lake Dianshan and Lake Changdang is s = 0.76(Chl-a = 9 mg/m3), s = 0.87(Chl-a = 24 mg/m3) and s = 0.72(Chl-a = 35 mg/m3), respectively. Given the results of the stressor–response relationship analysis, we conclude that reductions in P input represent the most feasible and least costly approach for managing eutrophication in the shallow lakes of the Lake Taihu Basin. To control the magnitude and duration of algal blooms in shallow lakes,reductions in P and N inputs are required. The 95 % CI bounds of slopes indicated that the interactions of nonnutrient factors with nutrients had strong impacts on the algal biomass in lightly eutrophicated Lake Kuilei. It is suggested that, in addition to reductions in n

关键词：富营养化湖泊藻类生物量分位数回归营养水平应激反应太湖流域回归分析中国

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Efficient interfacial charge transfer of BiOCl-In_(2)O_(3) step-scheme heterojunction for boosted photocatalytic degradation of ciprofloxacin

引用

Journal of Materials Science & Technology 2022年第26期121卷 236-244页

作者： Kaiqiang Xu Jie Shen Shiying Zhang Difa Xu xiaohua chen College of Materials Science and Engineering Hunan UniversityChangsha 410082China Hunan Key Laboratory of Applied Environmental Photocatalysis Changsha UniversityChangsha 410005China

BiOCl as a representative layered bismuth-based photocatalyst with Sillén-structure has aroused wide public concern on photocatalytic ***,the photocatalytic efficiency of pristine BiOCl is currently restricted by its low optical absorption and charge separation ***,step-scheme(S-scheme)heterojunctions of In_(2)O_(3) nanoparticle and BiOCl micron-sheet were constructed by a convenient molten salt method by using a LiNO_(3)-KNO_(3) *** In_(2)O_(3)-BiOCl heterojunctions exhibit higher optical absorption performance from 380 nm to 700 nm than the pristine BiOCl and enhanced photocatalytic property toward ciprofloxacin(CIP)degradation under Xenon lamp *** sample 20%In_(2)O_(3) -BiOCl showed the highest photodegradation efficiency,attaining 91%removal of CIP within 35 min,which was 39.6 times and 3.2 times higher than that of pristine In_(2)O_(3) and BiOCl,*** improved photodegradation property mainly resulted from the novel S-scheme mechanism,which boosted highly efficient separation of the photo-induced *** photoluminescence spectrometric test and transient photocurrent response results demonstrated that In_(2)O_(3)-BiOCl composite exhibited efficient separation of photo-generated charge *** work would provide new insights into the design of novel S-scheme photocatalytic systems with applicability in photocatalytic water treatment.

关键词： Step-scheme photocatalyst In_(2)O_(3) BiOCl Photocatalytic activity Ciprofloxacin

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Deformation Mechanism in Fe_(61)Mn_(18)Si_(11)Cr_(10) Medium Entropy Alloy Under Different Strain Rates

引用

Acta Metallurgica Sinica(English Letters) 2021年第8期34卷 1109-1119页

作者： Shaoheng Sun Yun Zhang Zhiyong Xue Jiankun Lin xiaohua chen Institute of Advanced Materials North China Electric Power UniversityBeijing 102206China Institute of Engineering Technology University of Science and Technology BeijingBeijing 100083China State Key Laboratory for Advanced Metals and Materials University of Science and Technology BeijingBeijing 100083China

We introduce a non-equiatomic Fe_(61)Mn_(18)Si_(11)Cr_(10) medium entropy alloy designed by subjecting it to transformation-induced plasticity upon deformation at room temperature. Microstructure characterization carried out using scanning electron microscopy(SEM), electron backscatter diffraction(EBSD), transmission electron microscopy(TEM) and X-ray diffraction(XRD) shows a homogeneous solid solution FCC + BCC structured dual phase. Investigations on the deformation substructures at specific strain levels via EBSD reveal the deformation-induced transformations of γ→α′ and γ→ ε. The strengths, particularly yield strength, of the designed alloy are found to be higher than these of the well-studied five component FeMnNiCoCr system for the introduction of the hard phase( α′-martensite). When tensile tests are performed at different strain rates of 10^(–4)s^(-1), 10^(–3)s^(-1), 10^(–2)s^(-1), the tested material exhibits a slightly negative strain rate sensitivity and work hardening rate sensitivity.

关键词： Medium entropy alloy Dual phase Transformation-induced plasticity(TRIP)effect Strain rate

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Effect of rotating magnetic field on the solidification microstructures of Pb-Sn alloys

引用

Science China(Technological Sciences) 2006年第3期49卷 274-282页

作者： MENG xiaohua chen Changle HONG Zhenyu WANG Jianyuan Department of Applied Physics Northwestern Polytechnical University Xi'an 710072 China Department of Applied Physics Northwestern Polytechnical University Xi'an 710072 China Department of Applied Physics Northwestern Polytechnical University Xi'an 710072 China Department of Applied Physics Northwestern Polytechnical University Xi'an 710072 China

The influence of the rotating magnetic field (RMF) on the solidification process of Pb-Sn binary alloys is studied by comparing the solidification microstructures under the common condition; RMF condition. It is found that the RMF can completely eliminate the gravity induced macrosegregation,; result in dendrite fragmentation; promote solute diffusion velocity. These differences are regarded as the effect of complicated melt flow caused by RMF. Moreover, when the content of the primary phase is small, many spherical microstructures form under the RMF condition. The analyses indicate that these special microstructures are likely the conjunction action of melt flow; concentration; temperature field uniformity caused by RMF.

关键词： rotating magnetic field, macrosegregation, dendrite fragmentation, melt flow.

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Small molecules in the treatment of COVID-19

引用

Signal Transduction and Targeted Therapy 2023年第1期8卷 38-76页

作者： Sibei Lei xiaohua chen Jieping Wu Xingmei Duan Ke Men State Key Laboratory of Biotherapy and Cancer Center West China HospitalSichuan UniversityChengdu 610041People’s Republic of China Department of Pharmacy Personalized Drug Therapy Key Laboratory of Sichuan Province Sichuan Academy of Medical Sciences&Sichuan Provincial People’s HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengdu 610072China

The outbreak of COVID-19 has become a global crisis,and brought severe disruptions to societies and *** now,effective therapeutics against COVID-19 are in high *** with our improved understanding of the structure,function,and pathogenic process of SARS-CoV-2,many small molecules with potential anti-COVID-19 effects have been *** far,several antiviral strategies were *** directly inhibition of viral proteins such as RdRp and M^(pro),interference of host enzymes including ACE2 and proteases,and blocking relevant immunoregulatory pathways represented by JAK/STAT,BTK,NF-κB,and NLRP3 pathways,are regarded feasible in drug *** development of small molecules to treat COVID-19 has been achieved by several strategies,including computer-aided lead compound design and screening,natural product discovery,drug repurposing,and combination *** small molecules representative by remdesivir and paxlovid have been proved or authorized emergency use in many *** many candidates have entered clinical-trial ***,due to the epidemiological features and variability issues of SARS-CoV-2,it is necessary to continue exploring novel strategies against *** review discusses the current findings in the development of small molecules for COVID-19 ***,their detailed mechanism of action,chemical structures,and preclinical and clinical efficacies are discussed.

关键词： finding treatment Small

来源：

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

Optimizing Mechanical Properties of AlCoCrFeNiTi_x High-Entropy Alloys by Tailoring Microstructures

引用

Acta Metallurgica Sinica(English Letters) 2013年第3期26卷 277-284页

作者： Yinfeng WANG Shengguo MA xiaohua chen Juyan SHI Yong ZHANG Junwei QIAO College of Materials Science and Engineering Taiyuan University of Technology State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Key Laboratory of Interface Science and Engineering in Advanced Materials Ministry of Education Taiyuan University of Technology

The effects of Ti additions and the heat treatment on the mechanical properties of AlCoCrFeNiTix （x = 0, 0.2, 0.3, 0.4 and 0.5） high-entropy alloys （HEAs） were studied. The results show that the dendrite phase with a body-centered-cubic （bcc） structure transforms into the interdendrite phase with a new bcc structure. With the increase of the Ti contents and heat-treatment temperature, the average hardness and yield strengths are greatly improved, and the highest hardness and yielding strength are 583 HV and 2.07 GPa, respectively in the investigated HEA system. The as-cast and annealed HEAs exhibit excellent mechanical properties, combining with high yielding strength and plasticity. The solid solution strengthening mechanism of Ti additions is responsible for the strengthening effect of AlCoCrFeNiTix HEAs.

关键词： High-entropy alloy Microstructure Compressive property Hardness Heat treatment

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Preparation and Crystallization of Carbon Nanotube/maleic Anhydride-grafted Polypropylene Composites

引用

Journal of Materials Science & Technology 2008年第2期24卷 279-284页

作者： xiaohua chen Jing HU Lingping ZHOU Wenhua LI Zi YANG Yanguo WANG College of Materials Science and Engineering Changsha University of Science and Technology Changsha 410076 China College of Materials Science and Engineering Hunan University Changsha 410082 China

Carbon nanotube （CNT）/maleic acid anhydride （MAH）-grafted polypropylene （PP） composites were prepared by in situ grafting method. Infrared spectroscopy showed that the CNTs were linked to PP by MAH grafting. The microstructures and calorimetry analysis indicated that the crystallization behaviors of the filled and unfilled PP were quite different. The addition of CNTs dramatically reduced the spherulite size, increased crystallization rate and improved the thermal stability of PP. These results confirmed the expected nucleant effect of CNT on the crystallization of PP. Scanning and transmission electron microscopy showed that the CNTs were dispersed homogeneously, indicating that the original CNT bundles were separated into individual tubes by the grafting.

关键词： Carbon nanotubes Chemical treatment Resins Crystallite size

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Biosorption of clofibric acid and carbamazepine in aqueous solution by agricultural waste rice straw

引用

Journal of Environmental Sciences 2013年第12期25卷 2384-2395页

作者： Zhanguang Liu Xuefei Zhou xiaohua chen Chaomeng Dai Juan Zhang Yalei Zhang Key Laboratory of Yangtze Water Environment of Ministry of Education State Key Laboratory of Pollution Control and Resource ReuseTongji University

Due to their widespread use, clofibric acid （CA） and carbamazepine （CBZ） have been frequently detected simultaneously at relatively high concentrations in aquatic environments. In this study, agricultural waste rice straw was employed as a potentially low-cost, effective and easy-to-operate biosorbent （RSB） to remove CA and CBZ. The adsorption of both pharmaceuticals followed pseudo second-order kinetics, and intraparticle diffusion was an important rate-limiting step. The adsorption isotherms of both drugs were fit well with Freundlich model. The adsorption of CA onto RSB was exothermic and was more likely to be dominated by physical processes, while the adsorption of CBZ was endothermic. Solution pH was determined to be the most important factor for CA adsorption, such that the adsorption capacity of CA onto RSB increased with the decline of solution pH. In the lower range of solution pH below 3. l, the CA removal efficiency was enhanced with the increase of biosorbent dosage. The CBZ removal efficiency was enhanced with the increase of RSB dosage without pH control. The maximum adsorption capacities were 126.3 mg/g for CA and 40.0 mg/g for CBZ.

关键词： biosorption clofibric acid carbamazepine rice straw agricultural waste uniform design

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

WRKY11 up-regulated dirigent expression to enhance lignin/lignans accumulation in Lilium regale Wilson during response to Fusarium wilt

引用

Journal of Integrative Agriculture 2024年第8期23卷 2703-2722页

作者： Jie Deng Zi’e Wang Wenyun Li xiaohua chen Diqiu Liu Faculty of Life Science and Technology Kunming University of Science and TechnologyKunming 650500China

Lilium are highly economically valuable ornamental plants that are susceptible to Fusarium wilt caused by Fusarium *** regale Wilson,a wild lily native to China,is highly resistant to *** this study,a WRKY transcription factor,WRKY11,was isolated from ***,and its function during the interaction between *** and *** was *** ectopic expression of LrWRKY11 in tobacco increased the resistance to F oxysporum,moreover,the transcriptome sequencing and UHPLC-MS/MS analysis indicated that the methyl salicylate and methyl jasmonate levels rose in LrWRKY11 transgenic tobacco,meanwhile,the expression of lignin/lignans biosynthesis-related genes including a dirigent(DiR)was *** lignin/lignans contents in LrWRKY11-transgenic tobacco also significantly increased compared with the wild-type *** addition,the resistance of *** scales in which LrWRKY11 expression was silenced by RNAi evidently decreased,and additionally,the expression of lignin/lignans biosynthesis-related genes including LrDIR1 was significantly ***,LrDIR1 and its promoter(PLrDIR1)sequence containing the W-box element were isolated from *** interaction assay indicated that LrWRKY11 specifically bound to the W-box element in PLrDIR1 and activated LrDIR1 ***,β-glucuronidase activity in the transgenic tobacco co-expressing LrWRKY11/PLrDIR1-β-glucuronidase was higher than that in transgenic tobacco expressing PLrDIR1-β-glucuronidase ***,the ectopic expression of LrDIR1 in tobacco enhanced the resistance to *** and increased the lignin/lignans *** brief,this study revealed that LrWRKY11 positively regulated *** resistance to *** through interaction with salicylic acid/jasmonic acid signaling pathways and modulating LrDIR1 expression to accumulate lignin/lignans.

关键词： Lilium regale Fusarium oxysporum WRKY transcription factor dirigent

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

Oxygen-Containing Functional Groups Regulating the Carbon/Electrolyte Interfacial Properties Toward Enhanced K^(+)Storage

引用

Nano-Micro Letters 2021年第12期13卷 29-43页

作者： Yufan Peng Zhen chen Rui Zhang Wang Zhou Peng Gao Jianfang Wu Hui Liu Jilei Liu Aiping Hu xiaohua chen College of Materials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology of Clean EnergyHunan Province Key Laboratory for Advanced Carbon Materials and Applied TechnologyHunan UniversityChangsha 410082People’s Republic of China Electrochemistry I Helmholtz Institute Ulm(HIU)89081 UlmGermany Karlsruhe Institute of Technology(KIT) P.O.Box 364076021 KarlsruheGermany College of Chemistry and Material Science Hunan Agricultural UniversityChangsha 410128People’s Republic of China

Oxygen-containing functional groups were found to e ectively boost the K^(+)storage performance of carbonaceous materials,however,the mechanism behind the performance enhancement remains ***,we report higher rate capability and better long-term cycle performance employing oxygen-doped graphite oxide(GO)as the anode material for potassium ion batteries(PIBs),compared to the raw *** in situ Raman spectroscopy elucidates the adsorption-intercalation hybrid K^(+)storage mechanism,assigning the capacity enhancement to be mainly correlated with reversible K^(+)adsorption/desorption at the newly introduced oxygen *** is unraveled that the C=O and COOH rather than C-O-C and OH groups contribute to the capacity *** on in situ Fourier transform infrared(FT-IR)spectra and in situ electrochemical impedance spectroscopy(EIS),it is found that the oxygen-containing functional groups regulate the components of solid electrolyte interphase(SEI),leading to the formation of highly conductive,intact and robust *** the systematic investigations,we hereby uncover the K^(+)storage mechanism of GO-based PIB,and establish a clear relationship between the types/contents of oxygen functional groups and the regulated composition of SEI.

关键词： Oxygen-containing functional groups Solid electrolyte interphase In situ spectroscopic characterization Potassium ion batteries

来源：

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

欢迎您,

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案：

请选择收藏分类：

通借通还

欢迎您,

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

在线全文

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：