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Soil Organic Carbon, Black Carbon, and Enzyme Activity Under Long-Term Fertilization

Journal of Integrative Agriculture 2014年第3期13卷 517-524页

作者： shao Xing-hua ZHENG Jian-wei Department of Life Science Shangrao Normal University

The present study aims to understand the effects of long-term fertilization on soil organic carbon （SOC）, black carbon （BC）, enzyme activity, and the relationships among these parameters. Paddy field was continuously fertilized over 30 yr with nine different fertilizer treatments including N, P, K, NP, NK, NPK, 2NPK （two-fold NPK）, NPK＋manure （NPKM）, and CK （no fertilization）, N, 90 kg urea-N ha^-1 yr^-1; P, 45 kg triple superphosphate-P205 ha^-1 yr^-1; K, 75 kg potassium chloride-K20 ha^-1 yr^-1; and pig manure, 22 500 kg ha^-1 yr^-1. Soil samples were collected and determined for SOC, BC content, and enzyme activity. The results showed that the SOC in the NPKM treatment was significantly higher than those in the K, P, and CK treatments. The lowest SOC content was found in the CK treatment. SOC content was similar in the N, NP, NK, NPK, 2NPK, and NPKM treatments. There was no significant difference in BC content among different treatments. The BC-to-SOC ratios （BC/SOC） ranged from 0.50 to 0.63, suggesting that BC might originate from the same source. Regarding enzyme activity, NPK treatment had higher urease activity than NPKM treatment. The urease activity of NPKM treatment was significantly higher than that of 2NPK, NP, N, P, K, CK, and NPKM treatment which produced higher activities of acid phosphatase, catalase, and invertase than all other treatments. Our results indicated that long-term fertilization did not significantly affect BC content. Concurrent application of manure and mineral fertilizers increased SOC content and significantly enhanced soil enzyme activities. Correlation analysis showed that catalase activity was significantly associated with invertase activity, but SOC, BC, and enzyme activity levels were not significantly correlated with one another. No significant correlations were observed between BC and soil enzymes. It is unknown whether soil enzymes play a role in the decomposition of BC.

关键词： organic carbon black carbon enzyme activity fertilization

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Succession of aquatic microbial communities as a result of the water quality variations in continuous water

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Journal of Environmental Sciences 2004年第5期16卷 772-778页

作者： WANGRong-chang WENXiang-hua QIANYi EnvironmentStimulationandPollutionControlStateKeyLaboratory DepartmentofEnvironmentalScienceandEngineeringTsinghuaUniversityBeijing100084China

The changes of structural and functional parameters of aquatic microbial communities in continuous water on campus of Tsinghua University, China are investigated by polyurethane foam unit(PFU) method. The measured compositions of the communities include alga, protozoa, and some metazoa(such as rotifers). The measured indicators of water quality include water temperature, pH value, dissolved oxygen(DO), potassium permanganate index(COD Mn ), total nitrogen(TN), total phosphorus(TP) and chlorophyll-a(Chla). The trophic level, expressed by the trophic level indices(TLIc), is assessed with analytic hierarchy process and principal component analysis(AHP-PCA) method. The changing trends of the structural and functional parameters of aquatic microbial communities, such as Margalef index of diversity(D), Shannon-weaver index of diversity (H), Heterotropy index(HI), number of species when the colonization gets equilibrium(S eq ), colonizing speed constant(G) and time spent when 90 percent of S eq colonized in PFU(T 90% ), are also analyzed. The experimental results showed the succession of aquatic microbial communities along the water flow is consistent with the water quality changes, so the parameters of microbial community can reflect the changes of water quality from the ecological view.

关键词： succession aquatic microbial community polyurethane foam unit(PFU) method water quality biodiversity biomonitoring

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不同宿主来源产气荚膜梭菌生物被膜形成前后药物敏感性分析

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动物医学进展 2025年第1期46卷 38-42页

作者：吴莹邵长军刘文华青岛农业大学动物医学院山东青岛266109 烟台市农科院山东烟台264200

为了检测5株不同宿主来源产气荚膜梭菌形成生物被膜能力及其对抗菌药物的敏感性差异,首先用纸片扩散法药敏试验测定5株不同来源的产气荚膜梭菌对7种抗菌药物的敏感性;筛选高敏药物测定各菌株的最小抑菌浓度(MIC);利用结晶紫染色法检测... 详细信息

为了检测5株不同宿主来源产气荚膜梭菌形成生物被膜能力及其对抗菌药物的敏感性差异,首先用纸片扩散法药敏试验测定5株不同来源的产气荚膜梭菌对7种抗菌药物的敏感性;筛选高敏药物测定各菌株的最小抑菌浓度(MIC);利用结晶紫染色法检测不同来源产气荚膜梭菌生物被膜形成能力和高敏药物对生物被膜的抑制和清除能力。药敏结果显示,5株不同宿主来源产气荚膜梭菌均对氨苄西林高度敏感,对其余6种抗菌药物有不同程度耐药;氨苄西林对不同菌株的MIC值在0.031~2.000μg/mL之间;所有菌株均能生成生物被膜,但生物被膜生成能力有差异;不同菌株在各自4、2、1 MIC下生物被膜的生成受到不同程度抑制,而亚抑菌浓度的氨苄西林能刺激生物被膜的生成,氨苄西林对已经生成的生物被膜不能完全清除。结果表明,不同来源产气荚膜梭菌形成生物被膜前后对药物敏感性不同,可为产气荚膜梭菌的临床用药选择及使用剂量提供一定的参考依据。

关键词：产气荚膜梭菌生物被膜最小抑菌浓度耐药性

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Dynamic Manipulability and Optimization of a Two DOF Parallel Mechanism

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Chinese Journal of Mechanical Engineering 2010年第4期23卷 403-409页

作者： shao hua WANG Jinsong WANG Liping GUAN Liwen Department of Precision Instrument and Mechanology Tsinghua University Beijing 100084 China

The dynamic dexterity is an important issue for manipulator design, some indices were proposed for analyzing dynamic dexterity, but they can evaluate the dynamic performance just at one pose in the workspaee of the manipulator, and can＇t be applied to dynamic design expediently. Much work has been done in the kinematic optimization, but the work in the dynamic optimization is much less. A global dynamic condition number index is proposed and applied to the dynamic optimization design the parallel manipulator. This paper deals with the dynamic manipulability and dynamic optimization of a two degree-of-freedom （DOF） parallel manipulator. The particular velocity and particular angular velocity matrices of each moving part about the part＇s pivot point are derived fi＇om the kinematic formulation of the manipulator, and the inertial force and inertial movement are obtained utilizing Newton-Euler formulation, then the inverse dynamic model of the parallel manipulator is proposed based on the virtual work principle. The general inertial ellipsoid and dynamic manipulability ellipsoid are applied to evaluate the dynamic performance of the manipulator, a global dynamic condition number index based on the condition number of general inertial matrix in the workspace is proposed, and then the link lengths of the manipulator is redesigned to optimize the dynamic manipulability by this index. The dynamic manipulability of the origin mechanism and the optimized mechanism are compared, the result shows that the optimized one is much better. The global dynamic condition number index has good effect in evaluating the dynamic dexterity of the whole workspace, and is efficient in the dynamic optimal design of the parallel manipulator.

关键词： dynamic manipulability dynamic optimization parallel manipulator

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Seismic performance evaluation of steel frame-steel plate shear walls system based on the capacity spectrum method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第3期9卷 322-329页

作者： Jian-hua shao Qiang GU Yong-kang SHEN College of Civil Engineering Hohai University Nanjing 210098 China Department of Civil Engineering Suzhou University of Science and Technology Suzhou 215011 China

This paper presents some methods that the standard acceleration design response spectra derived from the present China code for seismic design of buildings are transformed into the seismic demand spectra, and that the base shear force-roof displacement curve of structure is converted to the capacity spectrum of an equivalent single-degree-of-freedom （SDOF） system. The capacity spectrum method （CSM） is programmed by means of MATLABT.0 computer language. A dual lateral force resisting system of 10-story steel frame-steel plate shear walls （SPSW） is designed according to the corresponding China design codes. The base shear force-roof displacement curve of structure subjected to the monotonic increasing lateral inverse triangular load is obtained by applying the equivalent strip model to stimulate SPSW and by using the finite element analysis software SAP2000 to make Pushover analysis. The seismic performance of this dual system subjected to three different conditions, i.e. the 8-intensity frequently occurred earthquake, fortification earthquake and seldom occurred earthquake, is evaluated by CSM program. The excessive safety of steel frame-SPSW system designed according to the present China design codes is pointed out and a new design method is suggested.

关键词： Steel frame-steel plate shear walls (SPSW) system Capacity spectrum method (CSM) Seismic demand spectrum Base shear force-roof displacement Seismic performance evaluation

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TOWARDS EXPLORING WHEN AND WHAT PEOPLE REVIEWED FOR THEIR ONLINE SHOPPING EXPERIENCES

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Journal of Systems Science and Systems Engineering 2018年第3期27卷 367-393页

作者： Liangqiang Li hua Yuan Yu Qian Peiji shao School of Management and Economics University of Electronic Science and Technology of China Chengdu 611731 China

Web 2.0 technologies have attracted an increasing number of people with various backgrounds to become active online writers and viewers. As a result, exploring reviewers＇ opinions from a huge number of online reviews has become more important and simultaneously more difficult than ever before. In this paper, we first present a methodological framework to study the ＂purchasing-reviewing＂ behavior dynamics of online customers. Then, we propose a review-to-aspect mapping method to explore reviewers＇ opinions from the massive and sparse online reviews. The analytical and experimental results with real data demonstrate that online customers can be sectioned into groups in accordance with their reviewing behaviors and that people within the same group may have similar reviewing motivations and concerns for an online shopping experience.

关键词： E-commerce online review review dynamics opinion mining

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Focal autoimmune pancreatitis: Radiological characteristics help to distinguish from pancreatic cancer

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World Journal of Gastroenterology 2013年第23期19卷 3634-3641页

作者： Gao-Feng Sun chang-Jing Zuo Cheng-Wei shao Jian-hua Wang Jian Zhang Department of Radiology Changhai Hospital the Second Military Medical University

AIM: To identify the radiological characteristics of focal autoimmune pancreatitis (f-AIP) useful for differentiation from pancreatic cancer (PC). METHODS: Magnetic resonance imaging (MRI) and triple-phase computed tomography (CT) scans of 79 patients (19 with f-AIP, 30 with PC, and 30 with a normal pancreas) were evaluated retrospectively. A radiologist measured the CT attenuation of the pancreatic parenchyma, the f-AIP and PC lesions in triple phases. The mean CT attenuation values of the f-AIP lesions were compared with those of PC, and the mean CT attenuation values of pancreatic parenchyma in the three groups were compared. The diagnostic performance of CT attenuation changes from arterial phase to hepatic phase in the differentiation between f-AIP and PC was evaluated using receiver operating characteristic (ROC) curve analysis. We also investigated the incidence of previously reported radiological findings for differentiation between f-AIP and PC. RESULTS: The mean CT attenuation values of f-AIP lesions in enhanced phases were significantly higher than those of PC (arterial phase: 60 ± 7 vs 48 ± 10, P < 0.05; pancreatic phase: 85 ± 6 vs 63 ± 15, P < 0.05; hepatic phase: 95 ± 7 vs 63 ± 13, P < 0.05). The mean CT attenuation values of f-AIP lesions were significantly lower those of uninvolved pancreas and normal pancreas in the arterial and pancreatic phase of CT (P < 0.001, P < 0.001), with no significant difference at the hepatic phase or unenhanced scanning (P = 0.4, P = 0.1). When the attenuation value increase was equal or more than 28 HU this was considered diagnostic for f-AIP, and a sensitivity of 87.5%, specificity of 100% and an area under the ROC curve of 0.974 (95%CI: 0.928-1.021) were achieved. Five findings were more frequently observed in f-AIP patients: (1) sausageshaped enlargement; (2) delayed homogeneous enhancement; (3) hypoattenuating capsule-like rim; (4) irregular narrowing of the main pancreatic duct (MPD) and/or stricture of the common

关键词： Focal autoimmune pancreatitis Pancreatic cancer Computer tomography Magnetic resonance imaging Magnetic resonance cholangiopancreatography

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Insights into metals in individual fine particles from municipal solid waste using synchrotron radiation-based micro-analytical techniques

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Journal of Environmental Sciences 2015年第1期27卷 298-308页

作者： Yumin Zhu hua Zhang Liming shao Pinjing He State Key Laboratory of Pollution Control and Resources Reuse Tongji University Institute of Waste Treatment and Reclamation Tongji University Research and Training Center on Rural Waste Management Ministry of Housing and Urban–Rural Development of P.R. China

Excessive inter-contamination with heavy metals hampers the application of biological treatment products derived from mixed or mechanically-sorted municipal solid waste（MSW）. In this study, we investigated fine particles of 〈 2 mm, which are small fractions in MSW but constitute a significant component of the total heavy metal content, using bulk detection techniques. A total of 17 individual fine particles were evaluated using synchrotron radiation-based micro-X-ray fluorescence and micro-X-ray diffraction. We also discussed the association, speciation and source apportionment of heavy metals. Metals were found to exist in a diffuse distribution with heterogeneous intensities and intense hot-spots of 〈 10 μm within the fine particles. Zn–Cu, Pb–Fe and Fe–Mn–Cr had significant correlations in terms of spatial distribution. The overlapped enrichment, spatial association, and the mineral phases of metals revealed the potential sources of fine particles from size-reduced waste fractions（such as scraps of organic wastes or ceramics） or from the importation of other particles. The diverse sources of heavy metal pollutants within the fine particles suggested that separate collection and treatment of the biodegradable waste fraction（such as food waste） is a preferable means of facilitating the beneficial utilization of the stabilized products.

关键词： Municipal solid waste Fine particle Synchrotron radiation Micro-analytical technique Metal

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Manufacture and characteristics of Al2O3 composite coating on steel substrate by SHS process

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Rare Metals 2019年第7期38卷 704-712页

作者： Hai-Dong Gao Ze-hua Wang Jia shao College of Mechanics and Materials Hohai University

Many steel components are needed to be reinforced on their surface to have a high abrasive resistance and corrosion resistance. Based on self-propagating hightemperature synthesis, a process to making Al2O3 composite coatings on mild steel substrate in atmospheric environment with the help of simple auxiliary facilities was developed successfully. A pre-coated bilayer coating was employed. The effects of Fe content in pre-coated transition layer on phase composition, porosity and interfacial bon ding were studied using scanning electron microscopy (SEM), energy-dispersive spectrum (EDS) and X-ray diffraction (XRD). The thermal shock resistance and abrasive resistance were investigated. When Fe content changes from 0 wt% to 50 wt%, the bond quality at first becomes better and then worse gradually. When Fe content is less 20 wt%, there is a small gap between the transition layer and the substrate;when Fe contents are 30 wt% and 40 wt%, working layer, the transition layer and the substrate bond together well. The working layer is mainly composed of Al2O3, Fe-Cr and Al(Cr)2O3 phases and has a dense structure with porosity of less than 1 %. The coating has a good thermal shock resistance and abrasive resistance. The abrasive resistance of the working layer is about ten times that of the substrate.

关键词： Al2O3 composite coating Self-propagating high-temperature synthesis Interfacial bonding Thermal shock resistance Abrasive resistance

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Estimating source strengths of HCl and SO_2 emissions in the flue gas from waste incineration

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Journal of Environmental Sciences 2019年第1期31卷 370-377页

作者： hua Zhang Siyuan Yu Liming shao Pinjing He State Key Laboratory of Pollution Control and Resource Reuse Tongji University Institute of Waste Treatment & Reclamation College of Environmental Science and Engineering Tongji University Shanghai Institute of Pollution Control and Ecological Security Centre for the Technology Research and Training on Household Waste in Small Towns & Rural Area Ministry of Housing and Urban-Rural Development

HCl and SO_2 emission is one of the major concerns related to municipal solid waste incinerator(MSWI). In this study, a material flow analysis model was developed to estimate the HCl and SO_2 concentrations in the MSWI flue gases(FGs), and their concentrations in the full-scale MSWI were monitored. The calculated concentrations of HCl and SO_2 in the FG were 770–1300 mg/Nm^3 and 150–640 mg/Nm^3, respectively, in close agreement with the monitored values. More than 99% of Cl and 92% of S from the FG were captured into solid residues by the air pollution control(APC) systems. Moreover, since only 48.4%–67.5% of Cl and 21.3%–53.4% of S were transferred to the FG from the municipal solid waste(MSW), it was more reliable to estimate the source strengths and release amounts of HCl and SO_2 in the FG based on the amounts of Cl and S in the APC residues(AR) and exhaust gas rather than in the MSW. This simple method is easily applicable and the estimated results could provide scientific basis for the appropriate design and operation of the APC systems as well as corrosion control of heat recovery systems.

关键词： Municipal solid waste incineration Acid gas Hydrogen chloride Sulfur dioxide Source strength

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