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Inoculation with Phosphate-Solubilizing Fungi Diversifies the Bacterial Community in Rhizospheres of Maize and Soybean

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Pedosphere 2007年第2期17卷 191-199页

作者： wang Guang-hua jin Jian XU Mei-Na PAN Xiang-Wen C. TANG Laboratory of Black Soil Ecology Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Harbin 150081 （China）. Department of Agricultural Sciences La Trobe University Bundoora Vic 3086 （Australia）

Application of phosphate-solubilizing microorganisms (PSMs) has been reported to increase P uptake and plant growth. However, no information is available regarding the ecological consequences of the inoculation with PSMs. The effect of inoculation with phosphate-solubilizing fungal (PSF) isolates Aspergillus niger P39 and Penicillium oxalicum P66 on the bacterial communities in the rhizospheres of maize (Zea mays L. 'Haiyu 6') and soybean (Glycine max Merr. 'Heinong 35') was examined using culture-dependent methods as well as a culture-independent method, polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). Compared with the control, the number of culturable microbes for soybean was significantly greater with P39, whereas for maize, the same was significantly greater with P66. In addition, a greater number of microbes were found in the rhizosphere of maize compared with soybean. The fingerprint of DGGE for 16S rDNA indicated that inoculation with PSF also increased bacterial communities, with the P66 treatment having higher numbers of DGGE bands and a higher Shannon-Weaver diversity index compared with P39; the composition of the microbial community was also more complex with the P66 treatment. Overall, complex interactions between plant species and exotic PSMs affected the structure of the bacterial community in the rhizosphere, but plant species were more important in determining the bacterial community structure than the introduction of exotic microorganisms.

关键词： bacterial community diversity PCR-DGGE phosphate-solubilizing fungus rhizosphere

Bacterial Community Structure in a Mollisol Under Long-Term Natural Restoration, Cropping, and Bare Fallow History Estimated by PCR-DGGE

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Pedosphere 2009年第2期19卷 156-165页

作者： wang Guang-hua jin Jian LIU Jun-Jie CHEN Xue-Li LIU Ju-Dong LIU Xiao-Bing Key Laboratory of Black Soil Ecology Northeast Institute of Geography and Agroecology Chinese Academy of Sciences Harbin 150081 China

Soil microbial biomass and community structures are commonly used as indicators for soil quality and fertility. A investigation was performed to study the effects of long-term natural restoration, cropping, and bare fallow managements on the soil microbial biomass and bacterial community structures in depths of 0-10, 20 30, and 40-50 cm in a black soil （Mollisol）. Microbial biomass was estimated from chloroform fumigation-extraction, and bacterial community structures were determined by analysis of 16S rDNA using polymerase chain reaction-denaturing gradient gel electrophoresis （PCR- DGGE）. Experimental results showed that microbial biomass significantly declined with soil depth in the managements of restoration and cropping, but not in the bare fallow. DGGE profiles indicated that the band number in top 0-10 cm soils was less than that in depth of 20-30 or 40-50 cm. These suggested that the microbial population was high but the bacterial community structure was simple in the topsoil. Cluster and principle component analysis based on DGGE banding patterns showed that the bacterial community structure was affected by soil depth more primarily than by managements, and the succession of bacterial community as increase of soil depth has a similar tendency in the three managements. Fourteen predominating DGGE bands were excised and sequenced, in which 6 bands were identified as the taxa of Verrueomicrobia, 2 bands as Actinobacteria, 2 bands as α-Proteobacteria, and the other 4 bands as 8-Proteobacteria, Aeidobacteria, Nitrospira, and unclassified bacteria. In addition, the sequences of 11 DGGE bands were closely related to uncultured bacteria. Thus, the bacterial community structure in black soil was stable, and the predominating bacterial groups were uncultured.

关键词： bacterial community black soil denaturing gradient gel electrophoresis (DGGE) polymerase chain reaction (PCR) soil depth

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金黄色葡萄球菌平板计数法不确定度的评估

中国标准化 2025年第1期 250-255页

作者：姜勇王晓菡王金花张晓梅张鸿伟陶强雷质文达能特殊营养品(青岛)有限公司青岛海关技术中心

目的:针对奶粉基质,评估GB 4789.10—2016《食品安全国家标准食品微生物学检验金黄色葡萄球菌检验》中平板计数法的测量不确定度。方法:参考修订版RB/T 151《食品微生物定量检测的测量不确定度评估指南》设计评估方案,分别评估技术不确... 详细信息

目的:针对奶粉基质,评估GB 4789.10—2016《食品安全国家标准食品微生物学检验金黄色葡萄球菌检验》中平板计数法的测量不确定度。方法:参考修订版RB/T 151《食品微生物定量检测的测量不确定度评估指南》设计评估方案,分别评估技术不确定度、基质不确定度和分布不确定度,然后计算合成不确定度和扩展不确定度,最终可以根据实验室需求选择仅考虑技术不确定度,或者考虑全部不确定分量。结果:通过测试结果的统计分析,技术不确定度为0.0733 log10CFU/g;基质不确定度为0.0518 log10CFU/g;分布不确定度需要考虑泊松不确定度和确证不确定度,根据每次检测的结果查表或通过公式计算获得。结论:按照修订版RB/T 151进行不确定度评估,思路清晰,方案设计简洁,执行顺利,非常有利于实验室开展微生物检测方法的不确定度评估工作。

关键词：金黄色葡萄球菌平板计数法不确定度实验室内再现性 GB 4789.10—2016

Combined Effects of Cadmium and Butachlor on Microbial Activities and Community DNA in a Paddy Soil

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Pedosphere 2009年第5期19卷 623-630页

作者： wang jin-hua DING Hui LU Yi-Tong SHEN Guo-Qing College of Resources & Environment Shandong Agricultural University Tai'an 271018 (China) Department of Environment and Resource College of Agriculture and Biology Shanghai Jiao Tong University Shanghai201101 (China)

Due to frequent soil Cd contamination and wide use of butachlor in China,there is a need to assess their combined toxicity to soil *** combined effects of cadmium(Cd,10 mg kg-1 soil) and herbicide butachlor(10,50,and 100 mg kg-1 soil) on enzyme activities and microbial community structure in a paddy soil were assessed using the traditional enzyme assays and random amplified polymorphic DNA(RAPD) *** results showed that urease and phosphatase activities were significantly reduced by high butachlor concentration(100 mg kg-1 soil).When the concentrations of Cd and butachlor added were at a ratio of 1:10,urease and phosphatase activities were significantly decreased whereas enzyme activities were greatly improved at the ratio of 1:5,which indicated that the combined effects of Cd and butachlor on soil urease and phosphatase activities depended largely on their addition concentration *** amplified polymorphic DNA(RAPD) analysis showed loss of original bands and appearance of new bands when compared with the control *** amplified polymorphic DNA fingerprints suggested substantial differences between the control and treated soil samples,with apparent changes in the number and size of amplified DNA *** addition of high concentration butachlor and the combined impacts of Cd and butachlor significantly affected the diversity of the microbial *** analysis in conjunction with other biomarkers such as soil enzyme parameters would prove a powerful ecotoxicological *** investigations should be carried out to understand the clear link between RAPD patterns and enzyme activity.

关键词： biomarkers microbial community diversity phosphatase random amplified polymorphic DNA analysis urease

Local magnetic moment oscillation around an Anderson impurity on graphene

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Science China(Physics,Mechanics & Astronomy) 2025年第1期68卷 188-197页

作者： Shuai Li Zhen Ma jin-hua Gao School of Science Hebei University of Science and TechnologyShijiazhuang 050018China School of Electronics and Information Zhengzhou University of Light IndustryZhengzhou 450002China School of Physics and Wuhan National High Magnetic Field Center Huazhong University of Science and TechnologyWuhan 430074China

We theoretically investigate the spin resolved Friedel oscillation(FO)and quasiparticle interference(QPI)in graphene induced by an Anderson *** the impurity becomes magnetic,the resulted FO becomes spin dependent,which gives rise to a local magnetic moment oscillation with an envelop decaying as r^(-2) in real space in the doping ***,at half filling,the electron density and local magnetic moment will not oscillate but decay as r^(-3).Such spin resolved FO has both sublattice and spin ***,the local magnetic moment decay at half filling only occurs at one sublattice of graphene,which is quite like the phenomenon observed in the STM experiment(***ález-Herrero et al.,Science 352,437(2016)).We further give an analytic formula about such spin dependent FO based on the stationary phase ***,we study the interference of quasiparticles around the magnetic impurity by calculating the spin dependent Fourier-transformed local density of states(FT-LDOS).Our work gives a comprehensive understanding about the local magnetic moment oscillation around an Anderson impurity on graphene.

关键词： Friedel oscillation local magnetic moment graphene Anderson impurity

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我国煤巷锚杆支护技术的新发展

煤炭学报 2007年第2期32卷 113-118页

作者：王金华中国矿业大学(北京)

系统介绍了锚杆支护技术的最新研究成果.在支护理论方面,认为锚杆支护的主要作用在于控制锚固区围岩的离层、滑动、张开裂隙等扩容变形与破坏,最大限度地保持围岩完整性,避免有害变形出现;围岩地质力学测试仪器包括小孔径水压致裂地应... 详细信息

系统介绍了锚杆支护技术的最新研究成果.在支护理论方面,认为锚杆支护的主要作用在于控制锚固区围岩的离层、滑动、张开裂隙等扩容变形与破坏,最大限度地保持围岩完整性,避免有害变形出现;围岩地质力学测试仪器包括小孔径水压致裂地应力测量装置、围岩强度原位测量装置及钻孔窥视仪的技术特征与使用方法.论述了锚杆支护动态信息设计方法的特点与设计步骤,及面向现场工程技术人员使用的支护设计软件的组成与功能;分析了高强度锚杆支护材料的力学性能;介绍了国内锚杆施工机具的发展现状.

关键词：煤巷锚杆支护成套技术

Exponential Stability of Periodic Solution for Delayed Hopfield Networks

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Chinese Quarterly Journal of Mathematics 2008年第2期23卷 292-300页

作者： XIANG Hong-jun wang jin-hua Department of Mathematics Xiangnan University Chenzhou 423000 China

The paper is devoted to periodic attractor of delayed Hopfield neural networks with time-varying. By constructing Lyapunov functionals and using inequality techniques, some new sufficient criteria are obtained to guarantee the existence and global exponential stability of periodic attractor. Our results improve and extend some existing ones in [13-14]. One example is also worked out to demonstrate the advantages of our results.

关键词： Hopfield neural networks global exponential stability Lyapunov functional periodic solution

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正规和奇异H_∞控制器的统一表达式

控制理论与应用 2005年第5期22卷 820-824页

作者：王进华福州大学电气工程学院福建福州350002

给出了一种新的H∞控制器设计方法,通过引入设计时可选的非奇异实数阵,取消了控制器设计时对D矩阵的秩限制.适用于正规的H∞控制问题和奇异的H∞控制问题.对状态反馈等四种典型问题和输出反馈控制问题,给出了控制器存在的充分必要条件.... 详细信息

给出了一种新的H∞控制器设计方法,通过引入设计时可选的非奇异实数阵,取消了控制器设计时对D矩阵的秩限制.适用于正规的H∞控制问题和奇异的H∞控制问题.对状态反馈等四种典型问题和输出反馈控制问题,给出了控制器存在的充分必要条件.控制器通过Riccati方程的解,用参数化方法表示.输出反馈控制器,通过解两个Riccati方程得到.讨论了控制器的相关特性.

关键词： H∞控制鲁棒控制奇异系统不确定性

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二次型最优控制问题中的权矩阵与最优控制律

控制与决策 2007年第8期22卷 943-945,950页

作者：王进华福州大学电气工程与自动化学院福州350008

二次型最优的权矩阵选择是一个包含大量经验与技巧的问题.对此,研究权矩阵与最优控制律的关系:一个最优控制律,其对应的性能指标(权矩阵)是否唯一的问题.不论是单输入还是多输入情形,在系统能控性指数大于2,对应权矩阵的对角线元素有2... 详细信息

二次型最优的权矩阵选择是一个包含大量经验与技巧的问题.对此,研究权矩阵与最优控制律的关系:一个最优控制律,其对应的性能指标(权矩阵)是否唯一的问题.不论是单输入还是多输入情形,在系统能控性指数大于2,对应权矩阵的对角线元素有2个不为零的元素,且满足一定条件时,该性能指标对应的最优控制律,必有另一性能指标与之对应.

关键词：最优控制性能指标权矩阵 LQ问题