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Flexural behavior of high-strength,steel-reinforced,and prestressed concrete beams

Frontiers of Structural and Civil Engineering 2021年第1期15卷 227-243页

作者： Qing JIANG Hanqin WANG Xun CHONG Yulong FENG xianguo YE School of Civil and Hydraulic Engineering Hefei University of TechnologyHefei 230009China Anhui Key Laboratory of Civil Engineering and Materials Hefei 230009China College of Water Conservancy and Civil Engineering Xinjiang Agricultural UniversityUrumqi 830052China

To study the flexural behavior of prestressed concrete beams with high-strength steel reinforcement and high-strength concrete and improve the crack width calculation method for flexural components with such reinforcement and concrete,12 specimens were tested under static *** failure modes,flexural strength,ductility,and crack width of the specimens were *** results show that the failure mode of the test beams was similar to that of the beams with normal reinforced concrete.A brittle failure did not occur in the *** further understand the working mechanism,the results of other experimental studies were collected and *** results show that the normalized reinforcement ratio has a greater effect on the ductility than the concrete *** cracking-and peak-moment formulas in the code for the design of concrete(GB 50010-2010)applied to the beams were both found to be ***,the calculation results of the maximum crack width following GB 50010-2010 and EN 1992-1-1:2004 were considerably *** the context of GB 50010-2010,a revised formula for the crack width is proposed with modifications to two major factors:the average crack spacing and an amplification coefficient of the maximum crack width to the average *** mean value of the ratio of the maximum crack width among the 12 test results and the relative calculation results from the revised formula is 1.017,which is better than the calculation result from GB ***,the new formula calculates the crack width more accurately in high-strength concrete and high-strength steel reinforcement ***,finite element models were established using ADINA software and validated based on the test *** study provides an important reference for the development of high-strength concrete and highstrength steel reinforcement structures.

关键词： high-strength steel reinforcement high-strength concrete flexural behavior crack width

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Roles of initial current carrier in the distribution of field-aligned current in 3-D Hall MHD simulations

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Science China(Technological Sciences) 2008年第3期51卷 323-336页

作者： ZHANG xianguo PU ZuYin MA ZhiWei ZHOU XuZhi Institute of Space Physics and Applied Technology School of Earth and Space SciencePeking UniversityBeijing 100871China Institute of Plasma Physics Chinese Academy of SciencesHefei 230031China Institute of Fusion Theory and Simulation School of ScienceZhejiang UniversityHangzhou 310027China

A three-dimensional (3-D) Hall MHD simulation is carried out to study the roles of initial current carrier in the topology of magnetic field, the generation and distribu- tion of field aligned currents (FACs), and the appearance of Alfvén waves. Consid- ering the contribution of ions to the initial current, the topology of the obtained magnetic field turns to be more complex. In some cases, it is found that not only the traditional By quadrupole structure but also a reversal By quadrupole structure appears in the simulation box. This can explain the observational features near the diffusion region, which are inconsistent with the Hall MHD theory with the total ini- tial current carried by electrons. Several other interesting features are also emerged. First, motions of electrons and ions are decoupled from each other in the small plasma region (Hall effect region) with a scale less than or comparable with the ion inertial length or ion skin depth di=c/ωp. In the non-Hall effect region, the global magnetic structure is shifted in +y direction under the influence of ions with initial y directional motion. However, in the Hall effect region, magnetic field lines are bent in ?y direction, mainly controlled by the motion of electrons, then By is generated. Second, FACs emerge as a result of the appearance of By. Compared with the prior Hall MHD simulation results, the generated FACs shift in +y direction, and hence the dawn-dusk symmetry is broken. Third, the Walén relation in our simulations is consistent with the Walén relation in Hall plasma, thus the presence of Alfvén wave is confirmed.

关键词： collisionless magnetic reconnection Hall MHD simulation field aligned current (FAC) Alfvén wave Hall effects

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Magnetic and Microwave-absorption Properties of Graphite-coated (Fe, Ni) Nanocapsules

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Journal of Materials Science & Technology 2011年第7期27卷 607-614页

作者： Zhigao Xie Dianyu Geng xianguo Liu Song Ma Zhidong Zhang Shenyang National Laboratory for Materials Science Institute of Metal Research and International Centre for Material Physics Chinese Academy of Sciences 72 Wenhua Road Shenyang 110016 China

The structure, magnetic and microwave-absorption properties of graphite-coated （Fe, Ni） alloy nanocapsules, synthesized by the arc-discharge method, have been studied. High-resolution transmission electron microscopy shows that the nanocapsules have a core/shell structure with （Fe, Ni） alloy as the core and graphite as the shell. All （Fe, Ni） alloy nanocapsules/paraffin composites show good microwave-absorption properties. The optimal reflection loss （RL） was found for （Fe70Ni30）/C nanocapsules/paraffin composites, being -47.84 dB at 14.6 GHz for an absorber thickness of 1.99 mm, while the RL values exceeding -10 dB were found in the 12.4– 17.4 GHz range, which almost covers the Ku band （12.4–18 GHz）. For （Fe70Ni30）/C nanocapsules/paraffin composites, RL values can exceed -10 dB in the 11.4–18 GHz range with an absorber thickness of 1.91 mm, which cover the whole Ku band.

关键词： Magnetic Nanocapsules Microwave absorption

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亚麻籽主要功能成分及其生物活性研究进展

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食品与发酵工业 2024年第3期50卷 366-373页

作者：邹仙果关晓倩郑淼曹宇钦邓泽元杨开能静浙江工业大学食品科学与工程学院浙江杭州310014 南昌大学食品科学与技术国家重点实验室江西南昌330047

亚麻籽是一种营养价值极高的功能食品,富含不饱和脂肪酸、亚麻籽胶、木酚素和环肽等功能活性成分,具有抗氧化、抗炎、抗癌、抗高血压和预防心血管疾病等多种功效。该文综述了亚麻籽的主要功能成分及其近年来在生物活性方面的研究,着重... 详细信息

亚麻籽是一种营养价值极高的功能食品,富含不饱和脂肪酸、亚麻籽胶、木酚素和环肽等功能活性成分,具有抗氧化、抗炎、抗癌、抗高血压和预防心血管疾病等多种功效。该文综述了亚麻籽的主要功能成分及其近年来在生物活性方面的研究,着重介绍了环肽在结构、提取分离方法、活性功效方面的研究进展,并基于现有研究提出值得进一步挖掘的方向,以期为亚麻籽在功能食品领域的深入研究及开发利用提供理论依据和参考。

关键词：亚麻籽脂肪酸木酚素环肽生物活性

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钙改性水葫芦基生物炭吸附水中敌草隆的效能与机理

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化工进展 2024年第8期43卷 4630-4641页

作者：刘玉灿高中鲁徐心怡纪现国张岩孙洪伟王港烟台大学土木工程学院山东烟台264005 烟台大学环境与材料工程学院山东烟台264005

以水葫芦为原料、CaCl_(2)为改性剂,通过一步热解法制备了钙改性水葫芦基生物炭(CWHBC),基于表征技术分析了其表面形貌、比表面积、孔径分布、官能团组成等物化性能,并探究了其吸附去除水中敌草隆的效能与机理。结果表明,CWHBC比未改性... 详细信息

以水葫芦为原料、CaCl_(2)为改性剂,通过一步热解法制备了钙改性水葫芦基生物炭(CWHBC),基于表征技术分析了其表面形貌、比表面积、孔径分布、官能团组成等物化性能,并探究了其吸附去除水中敌草隆的效能与机理。结果表明,CWHBC比未改性生物炭(WHBC)具有更大的比表面积、更丰富的孔隙结构、更多的含氧官能团、更强的亲水性,这些物化性能的改变增强了生物炭的吸附能力。CWHBC对水中敌草隆的吸附符合准二级吸附动力学模型和Langmuir吸附等温线模型,表明该吸附以单层化学吸附为主,主要吸附机理为氢键作用、π-π作用和表面络合。单因素试验结果表明,CWHBC在各种条件下均具有良好的吸附性能,采用0.2mol/LHCl对其进行5次吸附/解吸循环后的吸附容量仍高达初次吸附容量的94.62%。因此,使用一步热解法制备的CWHBC可有效去除水中敌草隆,且具有较好的环境适应能力和重复使用性能。该研究提供了一种低成本、高效的吸附材料,能有效实现水葫芦的资源化利用,具有良好的工程应用前景与潜力。

关键词：生物炭钙改性吸附剂敌草隆吸附动力学机理

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Value Estimation of Greenhouse Gases Exchange in Wetland Ecosystem of Sanjiang Plain,China

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Chinese Geographical Science 2009年第1期19卷 55-61页

作者： LIU Xiaohui LU xianguo JIANG Ming WANG Xigang Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroeeology Chinese Academy of Sciences Changchun 130012 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China Hella Automotive Lighting Limited Company Changchun 130033 China

The objective of this study is to quantify the values of greenhouse gases(GHGs) exchange in carbon equivalents of marshes and paddy fields in the Sanjiang Plain,Heilongjiang Province,China. We obtained the GHGs exchange values based on comparable price by calculating the carbon sequestration values and the GHGs emission values of marshes and paddy fields respectively in four periods of 1982,1995,2000 and 2005. It is noted that the GHGs emission values are always negative. In this study,the marshes areas decreased from 1438977.0 to 775,132.2ha and the paddy fields areas increased from 417195.8 to 934205.0ha. The values of GHGs exchange of marshes varied from 135877.156×106 to 136882.534×106 yuan(RMB) and those of paddy fields varied from 1006.256×106 to 2767.645×106 yuan. The GHGs exchange values of marshes decreased from 1982 to 2005 on the whole,reversely,those of paddy fields increased,but those in 2005 were lower than those in 2000. In different periods,the GHGs exchange values were always higher in marshes than in paddy fields. The contribution rate of GHGs exchange values per unit area of marshes was also very high in different periods,and the maximum was up to 98.35% in 2005. As far as the whole wetland ecosystem(including marshes and paddy fields) ,assuming a linear change in GHGs exchange values,it represented a cumulative increase of 20926.757×106 yuan from 1982 to 2005. By adding GHGs exchange values increased during those four periods,we obtained a cumulative net increase values of GHGs exchange of wetland ecosystem of 18200.860×106 yuan. The results will be useful for understanding the indirect services provided by marshes and paddy fields.

关键词： carbon equivalents GHGs exchange values contribution rate cumulative value Sanjiang Plain

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格氏血厉螨的形态鉴别及相关研究现状

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热带医学杂志 2024年第3期24卷 442-447页

作者：刘如金郭宪国尹鹏吾大理大学病原与媒介生物研究所云南省自然疫源性疾病防控技术重点实验室云南大理671000

格氏血厉螨是常见的革螨种类之一,经常出现在啮齿动物等小型兽类体表。在动物分类上,格氏血厉螨隶属于皮刺螨总科、厉螨科、厉螨亚科中的血厉螨属。该螨的分类鉴定以雌性成虫形态为主要依据,其特征性钳齿毛是鉴别该螨的重要依据之一。... 详细信息

格氏血厉螨是常见的革螨种类之一,经常出现在啮齿动物等小型兽类体表。在动物分类上,格氏血厉螨隶属于皮刺螨总科、厉螨科、厉螨亚科中的血厉螨属。该螨的分类鉴定以雌性成虫形态为主要依据,其特征性钳齿毛是鉴别该螨的重要依据之一。格氏血厉螨是世界各地的广布种,宿主范围很广,宿主特异性较低。该螨可叮咬人体,除了起革螨性皮炎外,还可以作为肾综合征出血热等人兽共患病的传播媒介和贮存宿主,具有重要的医学意义。结合国内外文献,本文从分类地位、形态特征及鉴别要点、生活史及生态习性、染色体核型、超微结构、与疾病关系等方面,对格氏血厉螨的研究现状进行了综述。

关键词：蜱螨亚纲革螨格氏血厉螨分类鉴定

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Fuzzy Synthetic Evaluation of Water Quality of Naoli River Using Parameter Correlation Analysis

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Chinese Geographical Science 2008年第4期18卷 361-368页

作者： WANG Jianhua LU xianguo TIAN Jinghan JIANG Ming Key Laboratory of Wetland Ecology and En vironment Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Changchun 130012 China Hebei Cangzhou Teacher＇s College Cangzhou 061001 China Graduate University of the Chinese Academy of Sciences Beijing 100049 China

In order to improve the effectiveness of Fuzzy Synthetic Evaluation (FSE) models, a Parameter Correlation Analysis (PCA) was introduced into the FSE and a case study was carried out in the Naoli River in the Sanjiang Plain, Northeast China. The basic principle of the PCA is that the pairs of parameters which are highly correlated and linear with each other would contribute the same information to an assessment and one of them should be eliminated. The method of the PCA is that a correlation relationship among candidate parameters is examined before the FSE. If there is an apparent nonlinear or curvilinear relationship between two parameters, then both will be retained; if the correlation is significant (p<0.01), and the scatter plot suggests a linear relationship, then one of them will be deleted. However, which one will be deleted? For solving this problem, a sensitivity test was conducted and the higher sensitivity parameters remained. The results indicate that the original data should be preprocessed through the PCA for redundancy and variability. The study shows that introducing the PCA into the FSE can simplify the FSE calculation process greatly, while the results have not been changed much.

关键词： Parameter Correlation Analysis (PCA) Fuzzy Synthetic Evaluation (FSE) surface water quality Naoli River Sanjiang Plain

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A statistical approach to fit Gaussian part of full-energy peaks from Si(PIN) and SDD X-ray spectrometers

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Science China(Technological Sciences) 2014年第1期57卷 19-24页

作者： LI Zhe TUO xianguo SHI Rui YANG JianBo Provincial Key Laboratory of Applied Nuclear Techniques in Geosciences Chengdu University of Technology Institute of High Energy Physics Chinese Academy of Science Southwest University of Science and Technology

A new statistical fitting approach, named Statistical Distribution-Based Analytic （SDA） method, is proposed to fit single Gaussian-shaped Ka and KI3 X-ray peaks recorded by Si（PIN） and silicon drift detector （SDD）. In this method, we use the dis- crete distribution theory to calculate standard deviation of energy resolution a. The calibration of cr and energy （E） for two de- tectors between the energy ranges of 4.5-26 keV are also completed by measuring characteristic X-ray spectra of nineteen types of pure elements. With the spectrum fraction （SF） parameter proposed in this paper, the SDA method can be used to re- solve overlapping peaks. In measured spectra, the Gaussian part of X-ray peaks can be fitted by a Gaussian function with two parameters, ~ and SF. This new fitting approach is simpler than traditional methods and it achieves relatively good results when fitting the complex X-ray spectra of national standard alloy samples detected by Si（PIN） and SDD detectors. The 3（2 values are obtained for each spectrum to assess fitting results, and the SDA fitting method gives a preferable fit for the SDD detector.

关键词： Gaussian distribution Si(PIN) SDD EDXRF standard deviation of energy resolution

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Runoff Change of Naoli River in Northeast China in 1955–2009 and Its Influencing Factors

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Chinese Geographical Science 2012年第2期22卷 144-153页

作者： SONG Xiaolin LU xianguo LIU Zhengmao SUN Yonghe Key Laboratory of Wetland Ecology and Environment Northeast Institute of Geography and Agroecology Chinese Academy of Sci- ences Changchun 130012 China Graduate University of Chinese Academy of Sciences Beij＇ing 100049 China Heilongjiang Agricultural Reclamation Survey Design and Research Institute Harbin 150090 China Jiamusi Hydrological Bureau in Heilongjiang Province Jiamusi 154000 China

Runoff change and trend of the Naoli River Basin were studied through the time series analysis using the data from the hydrological and meteorological stations. Time series of hydrological data were from 1957 to 2009 for Bao′an station, from 1955 to 2009 for Baoqing station, from 1956 to 2009 for Caizuizi station and from 1978 to 2009 for Hongqiling station. The influences of climate change and human activities on runoff change were investigated, and the causes of hydrological regime change were revealed. The seasonal runoff distribution of the Naoli River was extremely uneven, and the annual change was great. Overall, the annual runoff showed a significant decreasing trend. The annual runoff of Bao′an, Baoqing, and Caizuizi stations in 2009 decreased by 64.1%, 76.3%, and 84.3%, respectively, compared with their beginning data recorded. The wet and dry years of the Naoli River have changed in the study period. The frequency of wet year occurrence decreased and lasted longer, whereas that of dry year occurrence increased. The frequency of dry year occurrence increased from 25.0%-27.8% to 83.9%-87.5%. The years before the 1970s were mostly wet, whereas those after the 1970s were mostly dry. Precipitation reduction and land use changes contributed to the decrease in annual runoff. Rising temperature and water project construction have also contributed important effects on the runoff change of the Naoli River.

关键词： runoff change hydrological parameters wetland land use human activities Naoli River

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