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Differences in Organic C Mineralization Between Aerobic and Submerged Conditions in Paddy Soils of Southern Jiangsu Province,China

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Agricultural Sciences in China 2011年第9期10卷 1410-1418页

作者： HAO Rui-jun LI Zhong-pei che Yu-ping State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 P.R. China Shanghai Institute of Landscape Gardening Shanghai 200232 P.R.China

Moisture regime plays a crucial role in the mineralization of soil organic carbon （SOC）. In this paper, the dynamics of SOC mineralization in typical paddy soils of Changshu, Jiangsu Province, China, was investigated by incubation test in laboratory. The differences in SOC mineralization under aerobic and submerged conditions of paddy soils were also studied. Results showed that the daily mineralization of SOC under different moisture regimes was significantly different in the whole incubation period, at the beginning of the incubation, it decreased quickly under aerobic condition, but increased rapidly under submerged condition, and both remained constant after 10 d of incubation. The differences in SOC mineralization were found to be mainly at the beginning period of the incubation and decreased along with the incubation time. Thus, the difference was not significantly different at the later incubation period. The respiration intensity, daily and cumulative mineralization of SOC under aerobic condition was 2.26-19.11, 0.96-2.41, and 0.96-2.41 times than those .under submerged condition, respectively. Statistic analyses showed that the higher the contents of microbial biomass carbon and nitrogen, the more significant difference in respiration intensity between aerobic and submerged conditions, but the higher the contents of microbial biomass nitrogen and dissolved organic carbon, the more significant difference in daily mineralization of SOC between the two conditions. The decrease in soil microbial activity under submerged condition was the main reason leading to the decrease in respiration intensity, but the decrease in SOC mineralization was also correlated with the changes in dissolved organic carbon over the whole incubation period.

关键词： moisture regime paddy soil SOC mineralization aerobic condition submerged condition difference

Preparation,characterization of Mo,Ag-loaded BiVO_4 and comparison of their degradation of methylene blue

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Science China chemistry 2012年第9期55卷 1770-1775页

作者： LIU KunJie CHANG ZhiDong LI WenJun che ping ZHOU HuaLei Department of chemistry and chemical Engineering School of Chemical and Biological EngineeringUniversity of Science and Technology BeijingBeijing 100083China

Two types of metal-loaded visible-light-driven photocatalysts,Mo-BiVO4and Ag-BiVO4,were synthesized by wet impregnation *** poperties were characterized by UV-vis diffuse reflectance spectroscopy,X-ray diffraction,field emission scanning electron microscopy,X-ray photoelectron spectroscopy and low temperature nitrogen *** activity of the obtained materials was investigated through degrading methylene blue(MB) solution under visible-light *** results reveal that both metal loaded-BiVO4catalysts have monoclinic scheelite *** and Ag exist as oxides on the surface of the *** changes of absorption in visible-light region,band gap(E g) and specific surface area(A BET) caused by loading Ag are more obvious than those caused by loading *** the isoelectric point of Ag-BiVO4decreases less than that of *** catalysts show higher photocatalytic activity than pure BiVO4,resulting in the significantly improved efficiency of degradation of *** the degradation efficiency of these two metal-loaded BiVO4photocatalysts is similar to each ***,mechanisms of such enhancement are *** decrease of isoelectric point helps Mo-BiVO4improve the degradation *** for Ag-BiVO4,the augmentation of absorption in visible-light region as well as the abatement of E g plays more important roles.

关键词： Mo-BiVO4 Ag-BiVO4 visible light photocatalyst isoelectric point

Effects of Glucose Addition on N Transformations in Paddy Soils with a Gradient of Organic C Content in Subtropical China

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Agricultural Sciences in China 2010年第9期9卷 1309-1316页

作者： JIA Jun-xian LI Zhong-pei LIU Ming che Yu-ping State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 P.R. China Graduate University Chinese Academy of Sciences Beijing 100049 P.R.China College of Art and Science Shanxi Agricultural University Taigu 030801 P.R. China

To better understand the interaction of N transformation and exogenous C source and manage N fertilization, the effects of glucose addition on N transformation were determined in paddy soils with a gradient of soil organic C content. Changes in N mineralization, nitrification and denitrification, as well as their response to glucose addition were measured by incubation experiments in paddy soils derived from Quaternary red clay in subtropical China. Mineralization and denitrification were changed in order of increasing soil fertilities： high 〉 middle 〉 low. During the first week of incubation, net N mineralization and denitrification rates in paddy soil with high fertility were 1.9 and 1.1 times of those in soil with middle fertility and 5.3 and 2.9 times of those in soil with low fertility, respectively. Addition of glucose decreased net N mineralization by approximately 78.8, 109.2 and 177.4% in soils with high, middle and low fertility, respectively. However, denitrification rates in soils with middle and low fertility were increased by 14.4 and 166.2% respectively. The highest nitrate content among the paddy soils tested was 0.62 mg kg-1 and the highest nitrification ratio was 0.33%. Addition of glucose had no obvious effects on nitrate content and nitrification ratio. It was suggested that the intensity of mineralization and denitrification was quite different in soils with different fertility, and increased with increasing soil organic C content. Addition of glucose decreased mineralization, but increased denitrification, and the shifts were greater in soil with low than in soil with high organic C content. Neither addition of glucose nor inherent soil organic C had obvious effects on nitrification in paddy soils tested.

关键词： paddy soils of subtropical China soil fertility glucose addition nitrogen transformation

GaN/PMMA nanocomposite:synthesis and optical properties

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Rare Metals 2010年第2期29卷 138-142页

作者： LIU Weibin ZHOU Hualei FANG Chunying WANG Mingwen ZHANG Yingtang cheN Ziyu che ping Department of Physics Beijing University of Aeronautics and Astronautics Beijing 100191 China School of Applied Science University of Science and Technology Beijing Beijing 100083 China

High crystalline quality wurtzite-GaN nanoparticles, with diameters of about 11 nm, well dispersed in a poly-methyl methacrylate polymer matrix, were synthesized using a routine two-step route and were structurally and optically *** as-prepared composite showed three broad overloading photoluminescence emission peaks with centers at 3.45, 3.29, and 3.10 *** 3.45 eV emission band is assigned to the recombination of the free exciton of GaN *** other two emission peaks possibly originate from the interfacial structure between the nanoparticles and polymer matrix or *** Fourier transform infrared（FTIR） spectrum further confirms the interfacial interaction that can be described as R-（C=O）-O-（GaN particle）.

关键词： GaN nanocomposite synthesis optical properties

Discrepancy in Response of Rice Yield and Soil Fertility to Long-Term chemical Fertilization and Organic Amendments in Paddy Soils Cultivated from Infertile Upland in Subtropical China

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Agricultural Sciences in China 2011年第2期10卷 259-266页

作者： LIU Ming LI Zhong-pei ZHANG Tao-lin JIANG Chun-yu che Yu-ping State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil ScienceChinese Academy of SciencesNanjing 210008P.R.China Graduate University Chinese Academy of SciencesBeijing 100049P.R.China

From 1990,over 17 years field experiment was carried out in paddy field cultivated from infertile upland to evaluate the response of rice productivity,soil organic carbon（SOC）,and total N to long-term NPK fertilization or NPK combined with organic *** field trials included NPK（N,P,K fertilizer）,NPKRS（NPK combined with rice straw）,NPK2RS（NPK combined with double amount of rice straw）,NPKPM（NPK combined with pig manure） and NPKGM（NPK combined with green manure） and the cropping system was rice-rice（Oryza sativa L.） *** rice yield,straw biomass,and harvesting index increased steadily with cultivation time in all *** annual rice yield from 1991 to 2006 was ranged from 7 795 to 8 572 kg ha-1 among *** yields in treatments with organic amendments were usually higher than that in treatment with *** of SOC and total N also increased gradually in the cultivation years and reached the level of 7.82 to 9.45 and 0.85 to 1.03 g kg-1,respectively,in *** fertilities in treatments with chemical fertilization combined with organic amendments were relatively appropriate than those in treatment with *** was obvious discrepancy between cumulative characters of rice yield and soil organic fertility in newly formed paddy *** with relatively high rate of crop productivity improvement,cumulative rates of SOC and total N were much lower in our *** and total N contents were still less than half of those in local highly productive paddy soils after 17 years cultivation in subtropical *** work helps to better understand the development of infertile paddy soils and to estimate the potential of yield improvement in this region.

关键词： paddy field rice yield SOC total N long-term field experiment

A New Family of Ce6MoO15 as Fast Oxide Ion Conductor

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Journal of Rare Earths 2004年第z2期22卷 95-97页

作者： Feng Jing Bo Qibing che ping Wang Jingping Liu Jianfen Lu Minfeng Zhang Deping Fang Daqing Cao Xueqiang Meng Jian Key Laboratory of Rare Earth chemistry and Physics Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Key Laboratory of Rare Earth Chemistry and PhysicsChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Key Laboratory of Rare Earth Chemistry and PhysicsChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Key Laboratory of Rare Earth Chemistry and PhysicsChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Key Laboratory of Rare Earth Chemistry and PhysicsChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Key Laboratory of Rare Earth Chemistry and PhysicsChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Key Laboratory of Rare Earth Chemistry and PhysicsChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Key Laboratory of Rare Earth Chemistry and PhysicsChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Key Laboratory of Rare Earth Chemistry and PhysicsChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China Key Laboratory of Rare Earth Chemistry and PhysicsChangchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China

A novel solid solution Ce6MoO15 was achieved. Their structure and oxide ionic conductivity were *** on Ce6MoO15, rare earth element substitution on cerium site shows that all resulting oxides enhance the conductivity ... 详细信息

关键词： Ce6MoO15 fast oxide ion conductor rare earths

An MILP Approach for a Profit-Based Unit Commitment Problem with Emissions Penalty

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An MILP Approach for a Profit-Based Unit Commitment Problem ...

一种利用混合模型研究基因与疾病间关联的方法

第26届中国控制与决策会议

作者： ping che Gang Shi Department of Mathematics Northeastern University

In this paper, we present a mixed-integer linear programming（MILP） formulation for a profit-based unit commitment problem with nonlinear emissions penalty. The quadratic fuel cost function and emissions function are approximated by piecewise linear functions, respectively, while the nonlinear emissions penalty is equivalently transformed into a mixed-integer linear form. Ramp rate limits and minimum up-time and down-time constraints are also considered in the proposed formulation. The resulting MILP model is solved by using a commercial solver. Numerical results on test cases of different scales indicate the effectiveness of the proposed MILP approach.

关键词： MILP Unit commitment Emissions penalty Deregulated electricity market

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东北师大学报（自然科学版） 2009年第2期41卷 40-45页

作者：车平东北大学理学院辽宁沈阳110004 东北师范大学数学与统计学院吉林长春130024

给出了将多位点基因型信息作为混杂因子的协变量,利用混合模型讨论在病例-对照研究中,当被研究群体中存在着分层现象时,被研究基因与疾病之间关联的一种新的方法.在子群体内部满足Hardy-Weinberg平衡时,此方法充分地利用已知信息,用基... 详细信息

给出了将多位点基因型信息作为混杂因子的协变量,利用混合模型讨论在病例-对照研究中,当被研究群体中存在着分层现象时,被研究基因与疾病之间关联的一种新的方法.在子群体内部满足Hardy-Weinberg平衡时,此方法充分地利用已知信息,用基因标识物将群体分层,并估计出被研究基因与疾病之间的关联性,同时还考虑了多位点基因型数据有缺失的情况.

关键词：混合模型关联混杂病例-对照研究 EM算法

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泥岩遇水软化微观机理研究

同济大学学报（自然科学版） 2007年第7期35卷 866-870页

作者：黄宏伟车平同济大学岩土及地下工程教育部重点实验室上海200092

通过扫描电镜与X射线衍射仪对不含蒙脱石的华北中生代煤系地层泥岩的微观结构与物质组成进行分析,研究了该泥岩遇水软化过程中微观结构随时间变化的动态特征.研究表明:泥岩中的矿物颗粒在水的作用下,颗粒间的连结将逐渐破坏,使水分进入... 详细信息

通过扫描电镜与X射线衍射仪对不含蒙脱石的华北中生代煤系地层泥岩的微观结构与物质组成进行分析,研究了该泥岩遇水软化过程中微观结构随时间变化的动态特征.研究表明:泥岩中的矿物颗粒在水的作用下,颗粒间的连结将逐渐破坏,使水分进入层状颗粒之间,从而在岩石内部产生不均匀内应力以及大量的微孔隙.这些微孔隙的出现及其吸附效应的影响,进一步破坏了岩石的内部结构体系,使泥岩在宏观上产生软化崩解的现象.可见,泥岩内部结构体系的特点是其软化崩解的真正原因,而是否含有蒙脱石并非泥岩软化崩解的决定性因素.

关键词：泥岩软化泥化微观机理