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A flow cytometer based protocol for quantitative analysis of bloom-forming cyanobacteria(Microcystis) in lake sediments

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Journal of Environmental Sciences 2012年第9期24卷 1709-1716页

作者： Quan Zhou Wei Chen Huiyong Zhang Liang Peng Liming Liu Zhiguo Han neng wan Lin Li Lirong Song State Key Laboratory of Freshwater Ecology and Biotechnology Institute of Hydrobiology Chinese Academy of Sciences Wuhan 430072 China Graduate School of Chinese Academy of Sciences Beijing 100039 China Zealquest Laboratory for Ecological Research Zealquest Scientific Technology Co. Ltd. Shanghai 200333 China Changshu Institute of Technology Changshu 215500 China

A quantitative protocol for the rapid analysis of Microcystis cells and colonies in lake sediment was developed using a modified flow cytometer, the CytoSense. For cell enumeration, diluted sediment samples containing Microcystis were processed with sonication to disintegrate colonies into single cells. An optimized procedure suggested that 5 mg dw （dry weight）/mL dilution combined with 200 W x 2 min sonication yielded the highest counting efficiency. Under the optimized determination conditions, the quantification limit of this protocol was 3.3x104 cells/g dw. For colony analysis, Microcystis were isolated from the sediment by filtration. Colony lengths measured by flow cytometry were similar to those measured by microscopy for the size range of one single cell to almost 400 ~tm in length. Moreover, the relationship between colony size and cell number was determined for three Microcystis species, including Microcystisflos-aquae, M. aeruginosa and M. wessenbergii. Regression formulas were used to calculate the cell numbers in different- sized colonies. The developed protocol was applied to field sediment samples from Lake Taihu. The results indicated the potential and applicability of flow cytometry as a tool for the rapid analysis of benthic Microcystis. This study provided a new capability for the high frequency monitoring of benthic overwintering and population dynamics of this bloom-forming cyanobacterium.

关键词： flow cytometry benthic Microcystis cell enumeration colony size measurement

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Lime and Phosphate Could Reduce Cadmium Uptake by Five Vegetables Commonly Grown in South China

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Pedosphere 2011年第2期21卷 223-229页

作者： TAN wan-neng LI Zhi-An QIU Jing ZOU Bi LI Ning-Yu ZHUANG Ping wanG Gang South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 (China)

A pot experiment was conducted in artificially Cd-contaminated （5 mg Cd kg 1） soils to investigate the feasibility of using lime （3 g kg-1） or phosphate （80 mg P kg-1） to mitigate uptake of Cd by vegetables. Five common vegetables in South China, including lettuce （Lactuca sativa L. var. ramosa Hort.）, Chinese cabbage [Brassica rapa L. subsp. Chinensis （L.） var. parachinensis （L. H. Bailey） Hanect], Chinese broccoli （Brassica oleracea L. vat. albiflora Kuntze）, white amaranth （Amaranthus tricolor L.） and purslane （Amaranthus viridis L.）, were grown in the soils and harvested after 60 d. The results showed that liming significantly reduced Cd uptake by most vegetables by 40%-50% （or a maximum of 70%）, mainly due to immobilization of soil Cd. Increased availability of Ca in the soil might also contribute to the Cd uptake reduction as a result of absorption competition between Ca and Cd. Liming caused biomass reduction in white amaranth and purslane, but did not influence growth of the other vegetables. Phosphate decreased Cd uptake by vegetables by 12% 23%. Compared with lime, phosphate decreased, to a smaller extent, the bioavailability of Cd in most cases. Phosphate markedly promoted growth of vegetables. Changes in soil chemistry by adding lime or phosphate did not markedly influence nutrient uptake of vegetables except that lime increased Ca content and phosphate increased P content in shoots of the vegetables. The results suggested that a proper application of lime could be effective in reducing Cd uptake of vegetables, and phosphate could promote growth of the vegetables as well as alleviate the toxicity of Cd.

关键词： cadmium accumulation cadmium immobilization nutrient soil amendment

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五轴测量复杂曲面粗糙度及其无干涉方法

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计算机集成制造系统 2024年第2期30卷 469-481页

作者：陈鹏何金明袁圆姚宇峰常智勇万能西北工业大学机电学院陕西西安710072 陕西省“四主体一联合”航空发动机智能装配工程技术中心陕西西安710072 中国航发湖南动力机械研究所湖南株洲412000

针对航空复杂零件粗糙度检测难题,利用五轴测量机灵活性高、可达域广的特点,搭载粗糙度传感器,研究复杂曲面粗糙度测量方法。首先分析粗糙度传感器与工件位置的关系;然后研究传感器和工件的干涉判断方法,求解粗糙度五轴测量中测杆无干... 详细信息

针对航空复杂零件粗糙度检测难题,利用五轴测量机灵活性高、可达域广的特点,搭载粗糙度传感器,研究复杂曲面粗糙度测量方法。首先分析粗糙度传感器与工件位置的关系;然后研究传感器和工件的干涉判断方法,求解粗糙度五轴测量中测杆无干涉方位,对粗糙度可测区域进行预测;最后通过离心叶轮关键部位粗糙度检测实验验证算法的可行性和准确性。实验表明,基于五轴测量机的复杂曲面粗糙度检测是一种可行的接触式粗糙度检测方法,无干涉算法能够精确预测可测区域,在实现复杂零件关键部位粗糙度量化表达的同时大幅提高检测效率。

关键词：五轴测量粗糙度检测干涉判断可测区域预测

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Role of Low-Molecule-Weight Organic Acids and Their Salts in Regulating Soil pH

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Pedosphere 2008年第2期18卷 137-148页

作者： LI Zhi-An ZOU Bi XIA Han-Ping DING Yong-Zhen TAN wan-neng FU Sheng-Lei Ecological Research Center South China Botanical Garden Chinese Academy of Sciences Guangzhou 510650 （China）.

The process of organic materials increasing soil pH has not yet been fully understood. This study examined the role of cations and organic anions in regulating soil pH using organic compounds. Calcareous soil, acid soil, and paddy soil were incubated with different simple organic compounds, pH was determined periodically and CO2 emission was also measured. Mixing organic acids with the soil caused an instant decrease of soil pH. The magnitude of pH decrease depended on the initial soil acidity and dissociation degree of the acids. Decomposition of organic acids could only recover the soil pH to about its original level. Mixing organic salts with soil caused an instant increase of soil pH. Decomposition of organic salts of sodium resulted in a steady increase of soil pH, with final soil pH being about 2.7-3.2 pH units over the control. Organic salts with the same anions （citrate） but different cations led to different magnitudes of pH increase, while those having the same cations but different anions led to very similar pH increases. Organic salts of sodium and sodium carbonate caused very similar pH increases of soil when they were added to the acid soil at equimolar concentrations of Na^＋. The results suggested that cations played a central role in regulating soil pH. Decarboxylation might only consume a limited number of protons. Conversion of organic salts into inorganic salts （carbonate） was possibly responsible for pH increase during their decomposition, suggesting that only those plant residues containing high excess base cations could actually increase soil pH.

关键词： acid soil cation decarboxylation organic compounds soil acidity

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Searches for Dark Matter via Mono-W Production in Inert Doublet Model at the LHC

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Communications in Theoretical Physics 2018年第5期69卷 617-624页

作者： neng wan Niu Li Bo Zhang Huan Yang Min-Fu Zhao Mao Song Gang Li and Jian-You Guo Center of Basic Experiment West Anhui University Lu＇an 237012 China School of Physics and Material Science Anhui University Hefei 230039 China

The Inert Doublet Model(IDM) is one of the many beyond Standard Model scenarios with an extended scalar sector, which provide a suitable dark matter particle candidate. Dark matter associated visible particle production at high energy colliders provides a unique way to determine the microscopic properties of the dark matter particle. In this paper, we investigate that the mono-W + missing transverse energy production at the Large Hadron Collider(LHC),where W boson decay to a lepton and a neutrino. We perform the analysis for the signal of mono-W production in the IDM and the Standard Model(SM) backgrounds, and the optimized criteria employing suitable cuts are chosen in kinematic variables to maximize signal significance. We also investigate the discovery potential in several benchmark scenarios at the 14 TeV LHC. When the light Z_2 odd scalar higgs of mass is about 65 GeV, charged Higgs is in the mass range from 120 GeV to 250 GeV, it provides the best possibility with a signal significance of about 3σ at an integrated luminosity of about 3000 fb^(-1).

关键词： large hadron collider IDM dark matter

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Biological oyster shell waste enhances polyphenylene sulfide composites and endows them with antibacterial properties

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Chinese Journal of Chemical Engineering 2023年第5期57卷 118-131页

作者： Chi-Hui Tsou Rui Zeng neng wan Manuel Reyes De Guzman Xue-Fei Hu Tao Yang Chen Gao Xiaomei Wei Jia Yi Li Lan Rui-Tao Yang Ya-Li Sun School of Materials Science and Engineering Sichuan University of Science&EngineeringZigong 643000China Material Corrosion and Protection Key Laboratory of Sichuan Province Sichuan University of Science&EngineeringZigong 643000China Sichuan Zhixiangyi Technology Co.Ltd. Chengdu 610051China

To date,there is no research that deals with biological waste as fillers in polyphenylene sulfide(PPS).In this study,oyster shells were recycled and treated to prepare thermally-treated oyster shells(TOS),which were used as PPS fillers to make new bio-based antibacterial composite *** effect of varying the content of TOS was studied by means of structure and performance ***/TOS composites were demonstrated to have an antibacterial effect on the growth of E coli and *** analysis showed that when the TOS content was≥30%and 40%,the composite materials had an apparent inhibition *** analysis showed that the antibacterial activity increased with the TOS *** transform infrared spectroscopy indicated the formation of hydrogen bonds between the molecular chains of TOS and PPS and the occurrence of a coordination *** 10%TOS,the composite tensile strength reached a maximum value of 72.5 MPa,which is 9.65%higher than that of pure *** trend of bending properties is the same as that of tensile properties,showing that the maximum property was reached for the composite with 10%*** the same time,the crystallinity and contact angle were the highest,and the permeability coefficient was the *** fatigue test results indicated that for the composite with 10%TOS,the tensile strength was 23%lower than static tensile strength,and the yield strength was 10%lower than the static yield *** results of the study showed that TOS not only could reduce the cost of PPS,but also could impart antibacterial properties and enhance the mechanical and,barrier properties,the thermostability,as well as the crystallinity.

关键词： Oyster shell powder Polyphenylene sulfide(PPS) Antibacterial properties Filler Composite material Fatigue

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Situation and Development Tendency of Indoor Positioning

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China Communications 2013年第3期10卷 42-55页

作者：邓中亮余彦培袁协万能杨磊 School of Electronic Engineering Beijing University of Posts and Telecommunications State Key Laboratory of Information Photonics and Optical Communications

This paper introduces the significance of indoor positioning and analyzes the related problems. The latest research on indoor positioning is introduced. Further, the positioning accuracy and the cost of typical local and wide area indoor positioning systems are compared. The results of the comparison show that Time & Code Division-Orthogonal Frequency Division Multiplexing (TC-OFDM) is a system that can achieve real-time meter-accuracy of indoor positioning in a wide area. Finally, in this paper, we indicate that the seamless high-accuracy indoor positioning in a wide area is the development trend of indoor positioning. The seamless Location Based Services (LBS) architecture based on a heterogeneous network, key technologies in indoor positioning for decimeter-accuracy and seamless outdoor and indoor Geographic Information System (GIS) are elaborated as the most important research fields of future indoor positioning.

关键词： indoor positioning LBS review wide area local area TC-OFDM

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All-optical diode effect of a nonlinear photonic crystal with a defect

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Optoelectronics Letters 2006年第3期2卷 237-239页

作者： wanG Wei-jiang ZHOU Jin-yun XIAO wan-neng Faculty of Physics and Optoelectronic Engineering Guangdong University of Technology Guangzhou 510090 China State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-Sen University Guangzhou 510275 China

An all-optical diode behavior that uses a nonlinear one-dimensional photonic crystal (NPC) with a defect Kerr medium is numerically simulated by the use of a nonlinear finite-difference time-domain (NFDTD) *** numerical results show that for an incident pulse with appropriate intensity and temporal width,the transmittance can be several times greater in one direction of NPC than in the opposite direction at the pulse carrier frequency. This behaves like an all-optical diode and has promising applications in some areas such as optical isolation and all-optical *** ways to obtain low threshold of pulse field strength to realize an all-optical diode are also analyzed in detail.

关键词：光学二极管非线性光子晶体 Kerr介质有限微分时间域

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基于相关性分组的多元工序质量诊断模型

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计算机集成制造系统 2014年第7期20卷 1731-1736页

作者：牛青莫蓉万能西北工业大学现代设计与集成制造技术教育部重点实验室陕西西安710072

针对多元工序质量相关性诊断问题,提出一种基于分组技术的诊断算法。利用相关性分解定理,将质量分量的整体相关关系分解为一系列分量对之间的相关关系;以分量之间的相关关系为依据,利用因子分析法对质量分量进行分组,使同一组内分量之... 详细信息

针对多元工序质量相关性诊断问题,提出一种基于分组技术的诊断算法。利用相关性分解定理,将质量分量的整体相关关系分解为一系列分量对之间的相关关系;以分量之间的相关关系为依据,利用因子分析法对质量分量进行分组,使同一组内分量之间的相关关系尽可能大,不同组间的分量相关关系尽可能小;在忽略组间相关性的前提下,对同一组内的分量对建立相应的T2控制图,构成多元工序质量相关性诊断模型。理论分析和实践表明,对于分量之间的相关关系存在较大差异的多元工序质量,分组技术可以大幅度降低相关性诊断体系的规模。

关键词：多元工序质量相关性诊断分组技术因子分析 T2控制图

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等几何分析中Dirichlet边界条件的配点施加方法

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机械工程学报 2012年第5期48卷 157-164页

作者：陈涛莫蓉万能西北工业大学现代设计与集成制造技术教育部重点实验室西安710072

相对于传统有限元,等几何分析使用NURBS基函数统一表示几何和分析模型,它能消除传统有限元的网格离散误差,容易构造高阶协调单元。但是由于NURBS基函数缺乏插值性,控制顶点也不一定位于几何边界上,使得难以直接施加Dirichlet边界条件。... 详细信息

相对于传统有限元,等几何分析使用NURBS基函数统一表示几何和分析模型,它能消除传统有限元的网格离散误差,容易构造高阶协调单元。但是由于NURBS基函数缺乏插值性,控制顶点也不一定位于几何边界上,使得难以直接施加Dirichlet边界条件。针对这一问题,提出一种基于样条拟合的Dirichlet边界条件施加方法,通过引入一组边界配点来拟合边界条件。注意到不合适的配点策略会使得边界插值方程组奇异或者条件数过大,详细讨论配点选取的基本准则,提出两种鲁棒的配点方案:Greville横标和Chebyshev插值点法。并且将配点方法扩展到最小二乘形式,设计一种快速的场变量消去算法。通过实例验证上述方法的可行性和有效性。试验结果表明,各种配点策略的收敛率基本保持在一个量级,因此配点法的关键是选择稳定的配点方案。

关键词：等几何分析非插值性 Dirichlet条件边界配点法 Greville横标 Chebyshev插值点

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