检索结果-南通市图书馆

Correlation Between Yield Stress of Silty Mud Sediments and Continuous Oscillatory Shearing Properties

China Ocean Engineering 2022年第2期36卷 223-232页

作者： CHEN Xiao-hui zhang Min-xi yuE Shao-lin ZHOU huan yu Guo-liang SKLOE CISSEDepartment of Ocean and Civil Engineering Shanghai Jiao Tong UniversityShanghai 200240China CCCC Road&Bridge Special Engineering Co. Ltd.Wuhan 430061China

Analyzing the rheological properties of silty beds subjected to continuous oscillatory shear loading is crucial for understanding the morphological deformation of the seabed and ensuring safety in geological and marine engineering *** this study,the effects of oscillatory shearing properties on the yield stress(S_(u))of silty sediments were quantitatively *** effects of oscillatory shear strength(0-3),water content(26.6%-70.84%),and particle diameter(8.79-50μm)were examined extensively through a series of laboratory *** results indicated that the three aforementioned parameters were the major factors that affected the rheological characteristics of silty ***,their effects could be elucidated using the yield stress of cohesive sediments as the indicator *** ratio of yield stress(S_(u)/S_(u0))varied as the oscillatory shear strength increased up to a critical value,Λ_(cr).S_(u)bsequently,the ratio remained at a constant *** was deduced that the yield stress decreased with increasing oscillatory shear strength forΛΛ_(cr),the sediments entered an equilibrium fluidization stage,and the yield stress remained almost constant,irrespective of the oscillatory shear ***,during the equilibrium fluidization stage,it was observed that the ratio S_(u)/S_(u0)did not vary with water content but decreased as the particle diameter ***,based on regression analysis of the experimental data for non-equilibrium and equilibrium fluidization stages,a correlation between yield stress of silty sediments and continuous oscillatory shearing properties was *** correlation can aid in understanding the changes in solid resistance and assessing safety in piling ***,it can provide a theoretical guidance for reducing soil resistance in marine structures using mechanical vibrations.

关键词： silty sediments yield stress water content particle diameter oscillatory shear strength

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 Water Level Fluctuations on Wintering Goose Abundance in Poyang Lake Wetlands of China

引用

Chinese Geographical Science 2017年第2期27卷 248-258页

作者： XIA Shaoxia LIU yu CHEN Bin JIA Yifei zhang huan LIU Guanhua yu Xiubo Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources ResearchBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China The Second Surveying and Mapping Institute of Zhejiang Province Hangzhou 310012China Jiangxi Poyang Lake National Nature Reserve Authority Nanchang 330038China

The Poyang Lake is a Ramsar site and is the important over-wintering site for migratory waterbirds along the East Asian-Australasian Fly way. Examining the effects of water level fluctuations on waterbird abundance and analyzing the influencing mechanism is critical to waterbird protection in the context of hydrological alteration. In this study, the effect of water level regime on wintering goose abundance was examined and the influencing mechanism was interpreted. Synchronous waterbirds survey data, hydro- logical data, Moderate Resolution Imaging Spectroradiometer-Normalized Difference Vegetation Index （MODIS-NDVI） data and habi- tat data derived from Landsat TNUETM data and HJ/CCD data were combined. The satellite-derived Green Wave Index （GWI） based on MODIS-NDVI dataset was applied to detect changes in goose food resources. It was found that habitat size and vegetation conditions are key factors determining goose abundance. Geese numbers were positively correlated with habitat area, while intermediate range of vegetation productivity might benefit the goose abundance. Water level affects goose abundance by changing available habitat areas and vegetation conditions. We suggested that matching hydrological regime and exposed meadows time to wintering geese dynamics was crucial in the Poyang Lake wetlands. Our study could provide sound scientific information for hydrological management in the context of waterbird conservation.

关键词： water level fluctuation wintering geese Normalized Difference Vegetation Index (NDVI) Green Wave Index (GWI) waterbird habitat

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

Experimental Study on Towing Characteristics of Composite Bucket Wellhead Platform

引用

China Ocean Engineering 2024年第3期38卷 531-542页

作者： zhang Pu-yang LIU Ying-fei LE Cong-huan DING Hong-yan BAI yu State Key Laboratory of Hydraulic Engineering Intelligent Construction and Operation Tianjin UniversityTianjin 300072China

With the rapid development of large-scale development of marginal oilfields in China,simple wellhead platforms that are simple in structure and easy to install have become an inevitable choice in the process of oilfield ***,traditional simple wellhead platforms are often discarded after a single *** pursuit of a more costeffective approach to developing marginal oilfields,this paper proposes a new offshore oil field development facility—an integrated bucket foundation for wellhead *** verify the safety of its towing behavior and obtain the dynamic response characteristics of the structure,this paper takes a bucket integrated bucket foundation for wellhead platform with a diameter of 40 m as the research *** combining physical model tests and numerical simulations,it analyzes the static stability and dynamic response characteristics of the structure during towing,complete with the effects of the draft,wave height,wave period,and towing point height,which produce the dynamic responses of the structure under different influence factors,such as roll angle,pitch angle,heave acceleration and towing force as well as the sensibility to transport *** results show that the integrated bucket foundation for wellhead platform is capable of self-floating towing,and its movement is affected by the local environment,which will provide a reference for actual projects.

关键词： composite bucket foundation wellhead platform air flotation towing model test

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

2D/2D Ti_(3)C_(2) MXene/HTiNbO5 nanosheets Schottky heterojunction for boosting photothermal-assisted solar-driven photodegradation of tetracycline hydrochloride

引用

Journal of Materials Science & Technology 2024年第13期180卷 193-206页

作者： Wen Xiao huan yu Chenghao Xu Zhongyi Pu Xiangyu Cheng Fang yu Chao Liu Qinfang zhang Zhigang Zou School of Materials Science and Engineering Yancheng Institute of TechnologyYancheng 224051China Jiangsu Provincial Key Laboratory of Eco-Environmental Materials Yancheng Institute of TechnologyYancheng 224051China Eco-Materials and Renewable Energy Research Centre(ERERC) Nanjing UniversityNanjing 210093China

Developing high-efficiency photocatalysts for tetracycline hydrochloride(TCH)degradation is of great sig-nificance to ecosystems and human *** this work,a two-step process of exfoliation and re-stacking was performed to prepare re-stacked HTiNbO_(5) nanosheets(R-HTNS)and then coupled with Ti_(3)C_(2) MXene to construct Ti_(3)C_(2) MXene/R-HTNS(MX/RTS)with a 2D/2D Schottky *** 2D/2D het-erostructures between Ti_(3)C_(2) MXene and R-HTNS can produce an internal electric field and provide max-imum interface area for efficient charge transfer across the intimate *** photocatalytic perfor-mance of samples was evaluated by TCH degradation under simulated *** MX/RTS composites,with an optimal sample of 3-MX/RTS,show enhanced photocatalytic activity for TCH degradation com-pared with *** characterization results reveal that the introduction of Ti_(3)C_(2) MXene can signif-icantly increase specific surface area for providing more reactive sites and broaden the light absorption ***,the incident light energy is absorbed by the Ti_(3)C_(2) MXene component in MX/RTS compos-ites to generate photothermal energy(heat),which facilitates the charge carrier separation and surface reaction ***,the enhanced TCH photodegradation activity for MX/RTS composites is due to the introduction of Ti_(3)C_(2) MXene,which possesses the synergistic effect of the increased specific surface area,improved light-harvesting capacity,2D/2D Schottky heterojunction,and photothermal energy ***,the TCH photodegradation behavior is deliberated with a detailed discussion on various co-existing *** TCH photodegradation,the active radical species are determined for 3-MX/***-cording to the characterization results,the possible TCH photodegradation pathway and mechanism over 3-MX/RTS are *** work may offer a novel insight for constructing MXene-based heterostruc-tured photocatalysts with high efficiency.

关键词： HTiNbO_(5) Ti_(3)C_(2)MXene Schottky heterojunction Photodegradation Phototherma

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

Fluorine Substitution Effect on the Material Properties in Transparent Aromatic Polyimides

引用

Chinese Journal of Polymer Science 2022年第7期40卷 781-788页

作者： Wei-Feng Peng huan-yu Lei Xin-Xin zhang Lu-Hao Qiu Ming-Jun huang South China Advanced Institute for Soft Matter Science and Technology School of Emergent Soft MatterSouth China University of TechnologyGuangzhou510640China Guangdong Provincial Key Laboratory of Functional and Intelligent Hybrid Materials and Devices South China University of TechnologyGuangzhou510640China

The recent development of flexible display technology raised additional requirements for optical and electric properties of polyimides,accelerating the structure and property tunning of transparent *** unique electronic effect and steric hindrance effect of fluorine substitutions make fluorine-containing polyimides occupy an important position in the transparent polyimide *** this work,a series of transparent aromatic polyimides were prepared from a fixed 4,4’-(hexafluoroisopropylidene)diphthalic anhydride(6FDA)and biphenyl diamines with different substitute groups at the 2,2’,6,6’-*** systematically studied the effects of pendant groups on the thermal,mechanical,optical and dielectric properties of these 6FDA-based polyimides with the aid of density function theory(DFT)*** particular,we paid special attention to the simple but compact fluoro group *** simple fluoro substitution brought the advantages of maintaining the linearity of the backbone and dense polymer chain packing,which would minimize the weakening of polyimides’inherent thermal,dimensional and mechanical *** with trifluoromethyl substituted polyimides with the best optical transparency,polyimides containing fluoro substitutes exhibited slightly decreased optical transparency,but increased thermal and dimensional stability and higher mechanical *** results could shed light on the ultimate transparent polyimide film development toward the application in extreme working condition,e.g.,the colorless polyimide substrate film for the flexible display technology.

关键词： Polyimides Fluorine substitution Transparent Dielectric Colorless

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

Gram-scale synthesis of all-inorganic perovskite quantum dots with high Mn substitution ratio and enhanced dual-color emission

引用

Nano Research 2019年第7期12卷 1733-1738页

作者： Lvming Dong Zhuo Chen Lei Ye Yan yu Jianbing zhang huan Liu Jianfeng Zang School of Optical and Electronic Information and Wuhan National Laboratory for Optoelectronics Huazhong University of Science and TechnologyWuhan 430074China Innovation Institute Huazhong University of Science and TechnologyWuhan 430074China

Mn-doped all-inorganic perovskite quantum dots (QDs) provide prominent applications in the fields of low-cost light source or display,because of their remarkable properties including dual-color emission and reduced lead content,as well as high photoluminescence quantum yields (PLQYs) and high ***,the existing synthesis approaches usually require hash conditions,such as high temperature and nitrogen protection,which is a major hurdler for the practical *** addition,the significantly high Mn substitution ratio in CsPbX3 QDs is still *** real dual-color emission with two strong emission peaks in the Mn-doped all-inorganic perovskite QDs has attracted great *** we present a gram-scale approach to synthesize both CsPbxMn1-xCI3 and CsPb1-xMnxClyBr3-y QDs at 100 ℃ in the air with high Mn substitution ratio,up to 55.64% *** as-prepared CsPb1-xMnxClyBr3-y QDs exhibit high PLQYs of 62.41% and dual-color emission with two strong emission peaks around at 400-450 nm and 600 nm,*** enhanced peak at 400-450 nm is a result of the hybrid halides in CsPbBrxCl3-x ***,the unique advantage of the optical emission and high PLQYs properties of the CsPbxMn1-xCl3 QDs has been demonstrated as invisible ink for encryption applications and polymer *** gram-scale synthesis approach for Mn-doped all-inorganic perovskite QDs may boost the future research and practical applications of QDs-based white LED,spintronics,and molecular barcoding.

关键词： gram-scale enhanced dual-color emission all-inorganic perovskite quantum dots invisible ink polymer composites

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

Meta-Analysis of the Association between Mir-196a-2 Polymorphism and Cancer Susceptibility

引用

Clinical oncology and cancer researeh 2012年第1期9卷 63-72页

作者： huan zhang yu-liang Su Herbert yu Bi-yun Qian Department of Epidemiology and Biostatistics Tianjin Medical University Cancer Institute and Hospital Key Laboratory of Cancer Prevention and Therapy Tianjin Medical UniversityMinistry of Education Epidemiology Program University of Hawaii Cancer CenterHonolulu 96813HIUSA

Objective MicroRNA plays a vital role in gene expression, and microRNA dysregulation is involved in carcinogenesis. The miR- 196a-2 polymorphism rs11614913 is reportedly associated with cancer susceptibility. This meta-analysis was performed to assess the overall association of miR-196a-2 with cancer risk. Methods A total of 27 independent case-control studies involving 10,435 cases and 12,075 controls were analyzed for the rs11614913 polymorphism. Results A significant association was found between rs11614913 polymorphism and cancer risk in four genetic models （CT vs. TT, OR-1.15, 95%CI=1.05-1.27; CC vs. TT, OR=1.23, 95%CI=1.08-1.39; Dominant model, OR=1.17, 95%CI=1.06-1.30; Additive model, OR-1.08, 95%CI=1.01-1.14）. In the subgroup analysis of different tumor types, the C allele was associated with increased risk of lung, breast, and colorectat cancer, but not with liver, gastric, or esophageal cancer. In the subgroup analysis by ethnicity, a significantly increased risk of cancer was found among Asians in all genetic models, but no associations were found in the Caucasian subgroup. Conclusions The meta-analysis demonstrated that the miR-196a-2 polymorphism is associated with cancer susceptibility, especially lung cancer, colorectal cancer, and breast cancer among Asian populations.

关键词： MIRN196 microRNA human polymorphism neoplasms meta-analysis

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

Template Effect of Hydrophobically Associating Polymers on the Construction of Cuprous Oxide Micro Structure

引用

Chemical Research in Chinese Universities 2018年第1期34卷 138-144页

作者： DONG Lei LIU huan LI Yanjuan zhang Hongtao yu Liangmin JIA Lanni Key Laboratory of Marine Chemistry Theory and Technology Ministry of Education College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266100 P. R. China School of Chemistry and Chemical Engineering Jiangsu Normal University Xuzhou 221116 P R. China National Engineering Research Center for Marine Drugs Ocean University of China Qingdao 266071 P. R. China Marine Biomedical Research Instimte of Qingdao Qingdao 266071 P. R. China

To determine the template effect of hydrophobically associating copolymers（HACPs） on the morphology of nano/micro structures, six HACPs were synthesized and used as templates to biomimetically synthesize cuprous oxide（Cu2O）, an important semiconductor. This experiment showed a clear relationship between the associating state of the HACP molecules and the morphology of the Cu2O particles. Cu2O hollow spheres were preferentially prepared when the HACP molecules were in an intramolecular associating state. Furthermore, a Cu2O hexapod was easily obtained when the HACP molecules were in an intermolecular associating state. The morphologies of the Cu2O crystals prepared in the presence of the HACPs also confirmed this result.

关键词： Template Hydrophobically associating polymer Cuprous oxide Morphology

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

Printing High-resolution Micro-patterns by Solution Processes

引用

Chemical Research in Chinese Universities 2021年第5期37卷 1008-1018页

作者： zhang Kejie zhang Min LIU huan Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of Ministry of Education School of ChemistryBeijing Advanced Innovation Center for Biomedical EngineeringInternational Research Institute for Multidisciplinary ScienceBeihang UniversityBeijing100191P.R.China

The preparation of high-resolution micro-patterns is urgently demanded for developing opto-/electric-devices in various ***,solution processes have been commonly used for fabricating micro-patterned surfaces for its mild operation conditions,facile operability and *** this contribution,we reviewed recent processes on preparing micro-/nano-patterns using solution processes based the viewpoint of resolution,including inkjet printing,photolithography,micro-contact printing.

关键词： resolution preparing viewpoint

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

Masked Sentence Model Based on BERT for Move Recognition in Medical Scientific Abstracts

引用

Journal of Data and Information Science 2019年第4期4卷 42-55页

作者： Gaihong yu Zhixiong zhang huan Liu Liangping Ding N ational Science Library Chinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China W uhan Library Chinese Academy of SciencesWuhan 430071China

Purpose:Mo ve recognition in scientific abstracts is an NLP task of classifying sentences of the abstracts into different types of language *** improve the performance of move recognition in scientific abstracts,a novel model of move recognition is proposed that outperforms the BERT-based ***/methodology/approach:Prevalent models based on BERT for sentence classification often classify sentences without considering the context of the *** this paper,inspired by the BERT masked language model(MLM),we propose a novel model called the masked sentence model that integrates the content and contextual information of the sentences in move *** are conducted on the benchmark dataset PubMed 20K RCT in three ***,we compare our model with HSLN-RNN,BERT-based and SciBERT using the same ***:Compared with the BERT-based and SciBERT models,the F1 score of our model outperforms them by 4.96%and 4.34%,respectively,which shows the feasibility and effectiveness of the novel model and the result of our model comes closest to the state-of-theart results of HSLN-RNN at *** limitations:The sequential features of move labels are not considered,which might be one of the reasons why HSLN-RNN has better *** model is restricted to dealing with biomedical English literature because we use a dataset from PubMed,which is a typical biomedical database,to fine-tune our *** implications:The proposed model is better and simpler in identifying move structures in scientific abstracts and is worthy of text classification experiments for capturing contextual features of ***/value:T he study proposes a masked sentence model based on BERT that considers the contextual features of the sentences in abstracts in a new *** performance of this classification model is significantly improved by rebuilding the input layer without changing the structure of neural networks.

关键词： Move recognition BERT Masked sentence model Scientific abstracts

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：