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Energy dispersion of complex non-isolated vortices

Chinese science Bulletin 2011年第25期56卷 2713-2717页

作者： LUO ZheXian 1,2 1 Key Laboratory of Meteorological Disaster of Ministry of Education, Nanjing University of Information science and technology, Nanjing 210044, china 2 wuxi research center of environmental science and technology, wuxi 214031, china Key Laboratory of Meteorological Disaster of Ministry of Education Nanjing University of Information Science and Technology wuxi research center of environmental science and technology

Energy dispersion is a fundamental scientific problem in the study of natural disasters such as typhoons, heavy rain and earthquakes. The problem has been addressed by both multi-discipline research and forecast studies. The dynamics of isolated circular vortex energy dispersion have been solved. However, the disastrous results of typhoons and heavy rain often occur due to non-isolated circular vortices, the dynamics of which are explored in this paper. The energy dispersion characteristics of non-isolated vortices with complex structural patterns are examined using a linearized nondivergent barotropical vorticity equation model. In the initial field, a tropical cyclone (TC) vortex and a meso-scale vortex coexist, forming a complex structural pattern. An analytic solution based on a Fourier transform and simulations using a two-dimensional model show the following. (1) A wave train of TC-G-D may be created by the energy dispersion where the line connecting the three member centers of the wave train is parallel to the x axis in the case of an initial TC vortex without a meso-scale vortex. (2) A wave train of TC-G-D may also be created by energy dispersion. However, the line connecting the three member centers of the wave train would no longer be parallel to the x axis. Instead, they would form a triangle in the presence of the initial TC vortex with the meso-scale vortex. (3) There is a nonlinear relationship between the initial intensity of the meso-scale vortex and the base angle of the triangle. These results have the potential to be applied in the field of typhoon forecasting.

关键词：能量色散非隔离式旋涡非线性关系中尺度涡台风预报结构模式傅立叶变换

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Cytotoxicity of lambda-cyhalothrin on the macrophage cell line RAW 264.7

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Journal of environmental sciences 2010年第3期22卷 428-432页

作者： Quan Zhang, Cui Wang, Liwei Sun, Ling Li, Meirong Zhao research center of environmental science, College of Biological and environmental Engineering, Zhejiang University of technology, Hangzhou 310032, china. [a] research center of environmental science College of Biological environmental Engineering Zhejiang University of Technology Hangzhou 310032 China

The wide use and wide-spectrum toxicity of synthetic pyrethroids （SPs） insecticides make them an emerging ecotoxicological concern. Some previous studies showed that SPs possessed cytotoxicity in some immune cells such as human lymphocytes and rat bone marrow. However, the cytotoxicity of SPs to macrophages, which are crucial to innate immunity, has not been explored. In the present report, we investigated a new pyrethroid insecticide, lambda-cyhalothrin （LCT）, which may increase the generation of reactive oxygen species （ROS） and DNA damage levels and cause cytotoxicity in RAW 264.7 cells in dose- and time-dependent manners. The results for the first time implicated increased endogenous ROS and DNA damage as co-mediators of LCT-induced cytotoxicity in macrophages. Our results also suggested that macrophages were involved in synthetic pyrethroid-induced adverse immune effects. Considering the ubiquitous environmental presence of SPs, this study provided new information relative to the potential long-term physiological and immunological effects associated with chronic exposure to SPs. Hence, the potential immunotoxicity of SPs should be considered in assessing the safety of these compounds in sensitive environmental compartments.

关键词： lambda-cyhalothrin macrophage reactive oxygen species cytotoxicity

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Enantioselective separation and zebrafish embryo toxicity of insecticide beta-cypermethrin

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Journal of environmental sciences 2010年第5期22卷 738-743页

作者： Chao Xu,Wenqing Tu,Chun Lou,Yingying Hong,Meirong Zhao research center of environmental science,College of Biological and environmental Engineering,Zhejiang University of technology,Hangzhou 310032,china. [a] research center of environmental science College of Biological environmental Engineering Zhejiang University of Technology Hangzhou 310032 China

Enantioselectivity of chiral pollutants is receiving growing concern due to the difference in toxicology and environment fate between *** this study,enantiomers of insecticide beta-cypermethrin （beta-CP） were separated on selected chiral column by HPLC,and the toxicity of enantiomers was evaluated using the zebrafish embryo-larval *** enantiomers of beta-CP were baseline separated on Chiralcel OD and Chiralpak AD columns and detected by circular dichroism （CD） at 236 *** separation could be achieved at lower temperature （e.g.,20°C） and with lower levels of polar *** enantiomers were obtained on Chiralcel *** CD spectra of enantiomers were *** comparing the elution order with a previous similar study,the absolute configuration of beta-CP enantiomers was *** individual enantiomers were used in zebrafish embryo test,and the results showed that beta-CP enantioselectively induced yolk sac edema,pericardial edema and crooked *** 1R-cis-αS and 1R-trans-αS enantiomers showed strong developmental toxicities at concentration of 0.1 mg/L,while the 1S-cis-αR and 1S-trans-αR induced no malformations at higher concentration （e.g.,0.3 mg/L）.The results suggest that the enantioselective toxicological effects of beta-CP should be considered when evaluating its ecotoxicological effects.

关键词： beta-cypermethrin enantioselectivity zebrafish embryo chiral separation

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Degradation of nitrobenzene in wastewater by γ-ray irradiation

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Journal of environmental sciences 2004年第3期16卷 364-366页

作者： ZHANG Shu juan 1, FENG Shao hong 1, YU Han qing 1,* , LI Qian rong 2 (1 Department of Chemistry, University of science & technology of china, Hefei 230026, china. 2 research center for Physics & Chemistry, University of science & technology of china, Hefei 230026, china) Department of Chemistry University of Science & Technology of China Hefei 230026 China.

The degradation of nitrobenzene(NB) by γ ray irradiation was studied. The influences of dose rate and initial NB concentration were investigated in details. At a dose rate of 55 Gy/min, the degradation kinetics was pseudo first order at NB concentrations from 0 2 mmol/L to 4 0 mmol/L. At an initial NB concentration of 0 8 mmol/L, the degradation of NB at various dose rates also followed pseudo first order kinetics. Dissolved oxygen was found to have a positive effect on NB degradation. The degradation products were identified as nitrophenol, nitrosobenzene, and hydroquinone, and so on. Based on the product analysis, possible degradation pathways of nitrobenzene were proposed.

关键词： degradation irradiation nitrobenzene(NB) kinetics

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Adsorption of zinc on manganite(γ-MnOOH): particle concentration effect and adsorption reversibility

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Journal of environmental sciences 2004年第4期16卷 627-630页

作者： QIN Yan-wen1, PAN Gang 1,2,, ZHANG Ming-ming1, LI Xian-liang1 (1. State Key Laboratory of environmental Aquatic Chemistry, research center for Eco-environmental sciences, Chinese Academy of sciences, Beijing 100085, china. 2. Qingdao University of science & technology, Qingdao 266042, china) State Key Laboratory of environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China.

The adsorption and desorption processes of Zn(Ⅱ) on γ-MnOOH as a function of particle concentrations(C p) were studied. An obvious C p effect was observed in this adsorption system. The degree of adsorption hysteresis increased greatly with the increasing of C p, indicating that the extent of the real metastable-equilibrium states deviating from the ideal equilibrium state was enhanced with the increasing of C p. The C p-reversibility relationship confirmed the metastable-equilibrium adsorption(MEA) inequality(Pan, 1998a), which was the core formulation of the MEA theory. Because the MEA inequality was based on the basic hypothesis of MEA theory that adsorption density Γ is not a state variable, the C p-reversibility relationship gave indirect evidence to the basic hypothesis of MEA theory.

关键词： zinc γ-MnOOH adsorption reversibility

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Soil carbon pool in china and its global significance

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Journal of environmental sciences 1996年第2期8卷 249-254页

作者： Fang Jingyun, Liu Guohua, Xu Songling(research center for Eco-environmental science, ChineseAcademy of sciences, Beijing 100085, china) Res. Ctr. for Eco-Environ. science Chinese Academy of Sciences Beijing 100085 China

Soil organic carbon density and its related characteristics of 41 soil types all over china were analyzed by using data of 745 soil profiles , and size of soil carbon pool was estimated. As a result, area-weighted averages of these 41 soil types for bulk density, profile depth, organic carbon content and profile carbon were 1. 24 tC/m3, 86. 2 cm, 3. 04% and 19. 7 kg C/m2 respectively. Total size of soil carbon pool was 185. 68 × 1009tC, which is 29 times of that in terrestrial biomass of china and 12. 6% of global soil carbon pools. Because of its huge carbon pool, soil of china plays an important role in global carbon cycle.

关键词： china global climate change soil carbon content soil carbon pool soil type.

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ANALYSIS AND MEASUREMENT OF STOKES LAYER FLOWS IN AN OSCILLATING NARROW CHANNEL

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Journal of Hydrodynamics 2008年第6期20卷 770-775页

作者： PENG Xiao-xing HSU C. T. china Ship Scientific research center Wuxi 214082 China Department of Mechanical Engineering The Hong Kong University of Science and Technology Hong Kong China

The velocities of boundary layer flows between two parallel oscillating plates separated by small distance, i.e., in so called narrow channel, were theoretically and experimentally studied. The focus was on the laminar case where the Reynolds number ReA is much smaller than the transition value. The theoretical analysis of the Stokes layer in oscillating flow over a narrow channel was made first. Then Laser Doppler Velocimeter （LDV） was employed to measure the Stokes boundary layer above an oscillating flat plate and inside the oscillating narrow channel at various ReH numbers. At the same time, the phase angle difference along the vertical direction in both analysis and experiment were provided. The good agreements are shown between the measured results and the theoretical solution.

关键词： oscillation flow Stokes layer Laser Doppler Velocimeter (LDV) narrow channel

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Orientation-Singularity Representation and Orientation-Capability Computation of a Special Class of the Gough-Stewart Parallel Mechanisms Using Unit Quaternion

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Chinese Journal of Mechanical Engineering 2012年第6期25卷 1096-1104页

作者： LI Baokun1, 2, CAO Yi1, 3, *, ZHANG Qiuju1, and HUANG Zhen4 1 School of Mechanical Engineering, Jiangnan University, wuxi 214122, china 2 School of Mechanical Engineering, Anhui University of science and technology, Huainan 232001, china 3 State Key Laboratory of Fluid Power Transmission and Control, Hangzhou 310027, china 4 Robotics research center, Yanshan University, Qinhuangdao 066004, china 1. School of Mechanical Engineering Jiangnan University Wuxi 214122 China 2. School of Mechanical Engineering Anhui University of Science and Technology Huainan 232001 China 3. State Key Laboratory of Fluid Power Transmission and Control Hangzhou 310027 China 4. Robotics research center Yanshan University Qinhuangdao 066004 China

Singular configuration seriously affects the performance of the Gough-Stewart parallel mechanism and has attracted many researchers’ attentions. However, most of existing topics often focus on the position-singularity of the mechanism for a constant-orientation, but few reports research the orientation-singularity for a given position. In order to investigate the orientation-singularity of the Gough-Stewart parallel mechanisms with two dissimilar semi-regular hexagonal platforms for a given position, after constructing the discrimination matrix of the singular configuration of the mechanism and computing the determinant of this matrix by using unit quaternion as the orientation parameters which can avoid the singularities in parameterization, a general symbolic expression representing the three-dimensional orientation-singularity locus for a given position is obtained and the three-dimensional view of the orientation-singularity locus is further described. The orientation-singularity-free void exists inside the orientation-singularity locus, but the shape of the orientation-singularity-free void is irregular and inconvenient for the design of the mechanism. The minimal inscribed sphere of the three-dimensional orientation-singularity locus namely the orientation-singularity-free ball is described. The radius of the ball orientation-capability is used as the measurement for the orientation-singularity-free void size. A new efficient algorithm is proposed for the computation of the orientation-capability. Finally, the influences of the geometry parameters and the different positions of the mechanism on the orientation-capability are discussed. A new method of the singularity analysis of the Gough-Stewart parallel mechanism is advanced based on the unit quaternion, and the research finds have important referential value for the configuration parameters optimization of this class of the parallel mechanisms with the goal of having the maximal singularity-free zone.

关键词： parallel mechanism unit quaternion orientation-singularity orientation-singularity-free void orientation-capability

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Controlling uncertain fuzzy neutral dynamic systems with Markov jumps

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Journal of Systems Engineering and Electronics 2010年第3期21卷 476-484页

作者： Shuping He1,2 and Fei Liu1,2,1.Key Laboratory of Advanced Process Control for Light Industry,Ministry of Education,Jiangnan University,wuxi 214122,P.R.china 2.Institute of Automation,Jiangnan University,wuxi 214122,P.R.china Key Laboratory of Advanced Process Control for Light Industry Ministry of EducationJiangnan UniversityWuxi 214122P.R.China Institute of Automation Jiangnan UniversityWuxi 214122P.R.China

The robust H∞ control problems for stochastic fuzzy neutral Markov jump systems（MJSs） with parameters uncertainties and multiple time-delays are *** delays are respectively considered as constant and time varying,and the uncertain parameters are assumed to be norm *** means of Takagi-Sugeno fuzzy models,the overall closed-loop fuzzy dynamics are constructed through selected membership *** selecting the appropriate Lyapunov-Krasovskii functions,the sufficient condition is given such that the uncertain fuzzy neutral MJSs are stochastically stability for all admissible uncertainties and satisfies the given H∞ control *** stability and H∞ control criteria are formulated in the form of linear matrix inequalities,which can be easily checked in *** examples illustrate the effectiveness of the developed techniques.

关键词： neutral Markov jump system(MJS) Takagi-Sugeno fuzzy model time-delay uncertainty linear matrix inequality(LMI).

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Explanation of the mechanism of carcinogenesis and syntheses of anticancer agents with high selectivity

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science china Chemistry 2006年第1期49卷 44-62页

作者： DAI Qianhuan1,2 1. center of Chemistry and Bioengineering of Cancer research, Beijing Polytechnic University (Now known as Beijing Univer-sity of technology), Beijing 100022, china 2. center of environmental sciences, Peking University, Beijing 100871, china 1. center of Chemistry and Bioengineering of Cancer research Beijing Polytechnic University Beijing 100022 China 2. center of environmental sciences Peking University Beijing 100871 China

In 1979, the mechanism of chemical carcinogenesis, a challenging anddifficult scientific problem pending for a number of years, was explained by Dai Qianhuan. Themechanism named di-region theory predicted that a carcinogen always metabolizes to form a specialbi-functional alky-lating agent. This agent induces cross-linkages between the complementary basepairs in DMA and switches on initial mutageneses in genomes including point and frameshiftmutations. This, in turn, induces further deep mutageneses including the production of variouschimeric chromosomes, deletions and other aberrations found in genomes. In the end this initiatescarcinogenesis of the whole cell through the reverse transcription mechanism after a lengthyincubation period. Recently, this laboratory has verified that physical carcinogenesis, includingthe oncogenesis induced by radiation and asbestos as well as the carcinogenesis induced byendogenous factors such as estrogen or diethyl-stilbestrol switch on carcinogenesis by inducing theformation of cross-linkages between the complementary base pairs in DNA. Di-region theory has nowbeen supported by many experimental observations such as mutational spectra of various *** potential for carcinogenesis, teratogenesis, sterility and mutagenesis lumped together asgenetic toxicity appears to originate almost uniformly from the cross-linking between complementarybases, i.e. malignant cross-linking, which is in accordance with di-region theory. Other forms ofcross-linking between non-complementary bases, benign cross-linkings, show bi-functional alkylationanticancer activity but lack genetic toxicity. The predictable design and synthesis of a highselectivity anticancer agent with high efficacy and low genetic toxicity, a goal long pursued incancer chemotherapy, have been realized for the first time in this laboratory by inhibitingmalignant and heightening benign cross-linking using the principles of di-region theory. A series ofpatented new anticanc

关键词： mechanism of carcinogenesis, di-region theory, minoplatin, selectivity of anticancer agent, cross-linking between DNA bases, anticancer platinum complexes, predictive design of anticancer agent, second generation anticancer agent.

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