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我国环境税费政策效应分析——基于“三重红利”假设的检验 被引量:28
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作者 卢洪友 朱耘婵 《中国地质大学学报(社会科学版)》 CSSCI 北大核心 2017年第4期9-26,共18页
通过建立2003—2014年省级面板数据模型,实证检验我国环境税费政策对节能减排、经济增长以及要素收入分配的影响效应。结果显示:我国融入型环境税费制度安排,对环境改善的作用非常微弱;征收环境税费具有促进经济转型和产业结构优化升级... 通过建立2003—2014年省级面板数据模型,实证检验我国环境税费政策对节能减排、经济增长以及要素收入分配的影响效应。结果显示:我国融入型环境税费制度安排,对环境改善的作用非常微弱;征收环境税费具有促进经济转型和产业结构优化升级的作用,经济增长红利得到较好实现;由于环境税费负担能够转嫁,在一定程度上抵消了对企业污染排放行为的控制效果,同时因劳动要素受供求弹性影响承担了更多的税负,劳动收益率下降,环境税费政策使得要素收入分配中资本与劳动的差距拉大。实现绿色发展、改善要素收入分配,需要改革碎片化的融入型环境税费制度,确立环境保护税的主体税种地位,并扩大课税范围、优化税率设计。 展开更多
关键词 环境税费政策 “三重红利”效应 税制绿化
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“三生”维度下的乡村旅游集聚区发展效应研究 被引量:1
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作者 席瑶 《湖北农业科学》 2022年第2期24-28,共5页
为了提高乡村旅游聚集区的"三生"效应,通过马尔科夫模型、回归分析模型及层次分析方法,分别实现建构乡村旅游聚集区影响能力的时空变化预测模型、格局变化分析模型和影响效应评级模型,并对模型进行效应评测。结果表明,2008—2... 为了提高乡村旅游聚集区的"三生"效应,通过马尔科夫模型、回归分析模型及层次分析方法,分别实现建构乡村旅游聚集区影响能力的时空变化预测模型、格局变化分析模型和影响效应评级模型,并对模型进行效应评测。结果表明,2008—2020年,乡村旅游聚集区的发展为乡村带来38.63%的生产效益及15.82%的生活效益,但却损耗了5.71%的生态效益。经过驱动力控制设计,预测未来10年间将会实现34.25%的生态效益。 展开更多
关键词 “三生”效应 乡村旅游聚集区 时空 格局 驱动力
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“三效应”创新新时代思政“三问”模式——以高速公路企业为例
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作者 张佩 《中文科技期刊数据库(全文版)社会科学》 2021年第4期59-60,共2页
由于新时代网络产生各种新情况、新问题,给企业的思想政治工作带来一定的难度。目前企业思想政治工作方法相对陈旧单一,创新力度不够,越来越无法满足新时代下企业员工思想变化的需求特点,因此,新时代下企业应努力与时俱进,把握规律性,... 由于新时代网络产生各种新情况、新问题,给企业的思想政治工作带来一定的难度。目前企业思想政治工作方法相对陈旧单一,创新力度不够,越来越无法满足新时代下企业员工思想变化的需求特点,因此,新时代下企业应努力与时俱进,把握规律性,创新思想政治工作机制,需要从“做什么”“谁来做”以及“怎么做”这三个问题进行深入调查研究,努力探索“做什么”“谁来做”和“怎么做”的路径,不断提升思想政治工作的科学性、合理性和实效性。 展开更多
关键词 “三效应“ 新时代 思想政治 “三问”模式
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教师有效家访当力戒“三效应”
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作者 刘勇 《基础教育研究》 2021年第18期90-91,共2页
家庭是学校教育强有力的辅助,入户家访有着家校线上交流不可比拟的优势,是家校合作共赢的德育基础和重要内容。作为新时代教师的必修课,入户家访考验着教师的专业素养和交际能力。面对新鲜而陌生的教育情境、对象和内容,教师入户家访要... 家庭是学校教育强有力的辅助,入户家访有着家校线上交流不可比拟的优势,是家校合作共赢的德育基础和重要内容。作为新时代教师的必修课,入户家访考验着教师的专业素养和交际能力。面对新鲜而陌生的教育情境、对象和内容,教师入户家访要警惕话语情绪化、互信欠缺化的不良态势,力戒投射效应、晕轮效应、定势效应带来的负面影响,努力发挥入户家访的优势,共同营造家校互信的氛围。 展开更多
关键词 入户家访 “三效应 负面影响 家校互信力
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Numerical Investigations on Dynamic Stall Characteristics of a Finite Wing
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作者 JING Simeng CAO Chenkai +2 位作者 GAO Yuan ZHAO Qijun ZHAO Guoqing 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2024年第4期444-457,共14页
The paper examines the dynamic stall characteristics of a finite wing with an aspect ratio of eight in order to explore the 3D effects on flow topology,aerodynamic characteristics,and pitching damping.Firstly,CFD meth... The paper examines the dynamic stall characteristics of a finite wing with an aspect ratio of eight in order to explore the 3D effects on flow topology,aerodynamic characteristics,and pitching damping.Firstly,CFD methods are developed to calculate the aerodynamic characteristics of wings.The URANS equations are solved using a finite volume method,and the two-equation k-ωshear stress transport(SST)turbulence model is employed to account for viscosity effects.Secondly,the CFD methods are used to simulate the aerodynamic characteristics of both a static,rectangular wing and a pitching,tapered wing to verify their effectiveness and accuracy.The numerical results show good agreement with experimental data.Subsequently,the static and dynamic characteristics of the finite wing are computed and discussed.The results reveal significant 3D flow structures during both static and dynamic stalls,including wing tip vortices,arch vortices,Ω-type vortices,and ring vortices.These phenomena lead to differences in the aerodynamic characteristics of the finite wing compared with a 2D airfoil.Specifically,the finite wing has a smaller lift slope during attached-flow stages,higher stall angles,and more gradual stall behavior.Flow separation initially occurs in the middle spanwise section and gradually spreads to both ends.Regarding aerodynamic damping,the inboard sections mainly generate unstable loading.Furthermore,sections experiencing light stall have a higher tendency to produce negative damping compared with sections experiencing deep dynamic stall. 展开更多
关键词 finite wing dynamic stall aerodynamic damping 3D effects
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Simulation analysis on three-dimensional slope failure under different conditions 被引量:8
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作者 张科 曹平 +2 位作者 刘紫曜 胡惠华 龚道平 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第11期2490-2502,共13页
The failure mechanism of two-dimensional(2D) and three-dimensional(3D) slopes were investigated by using the strength reduction method.An extensive study of 3D effect was conducted with respect to boundary conditi... The failure mechanism of two-dimensional(2D) and three-dimensional(3D) slopes were investigated by using the strength reduction method.An extensive study of 3D effect was conducted with respect to boundary conditions,shear strength and concentrated surcharge load.The results obtained by 2D and 3D analyses were compared and the applicable scope of 2D and 3D method was analyzed.The results of the numerical simulation show that 3D effect is sensitive to the width of slip surface.As for slopes with specific geometry,3D effect is influenced by dimensionless parameter c/(γHtanφ).For those infinite slopes with local loading,external load has the major impact on failure mode.For those slopes with local loading and geometric constraints,the failure mode is influenced by both factors.With the increase of loading length,boundary condition exerts a more significant impact on the failure mode,and then 2D and 3D stability charts are developed,which provides a rapid and reliable way to calculate 2D and 3D factor of safety without iteration.Finally,a simple and practical calculation procedure based on the study of 3D effect and stability charts is proposed to recognize the right time to apply 2D or 3D method. 展开更多
关键词 three-dimensional slope slope stability three-dimensional effect strength reduction method failure mechanism
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郭世宝博士与加拿大华人新移民研究述评 被引量:1
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作者 万晓宏 《华侨华人历史研究》 CSSCI 北大核心 2012年第1期65-69,共5页
论文评述了加拿大卡尔加里大学教育学院教授郭世宝在加拿大华人新移民研究方面的学术成果。认为他在华人新移民、华人社团、移民的外国文凭认证、文化多元化与高等及成人教育研究方面成就突出,其中在华人新移民研究方面有两项理论创新:... 论文评述了加拿大卡尔加里大学教育学院教授郭世宝在加拿大华人新移民研究方面的学术成果。认为他在华人新移民、华人社团、移民的外国文凭认证、文化多元化与高等及成人教育研究方面成就突出,其中在华人新移民研究方面有两项理论创新:在华人新移民融合研究方面提出了"三重玻璃效应"理论;在华人新移民回流研究方面运用了"双重离散"理论。 展开更多
关键词 加拿大 新移民 移民研究 “三重玻璃效应 “双重离散” 郭世宝
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3-D Simulation of FINFET 被引量:1
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作者 刘恩峰 刘晓彦 韩汝琦 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第9期909-913,共5页
An SOI MOSFET with FINFET structure is simulated using a 3 D simulator. I V characteristics and sub threshold characteristics,as well as the short channel effect(SCE) are carefully investigated.SCE can be well c... An SOI MOSFET with FINFET structure is simulated using a 3 D simulator. I V characteristics and sub threshold characteristics,as well as the short channel effect(SCE) are carefully investigated.SCE can be well controlled by reducing fin height.Good performance can be achieved with thin height,so fin height is considered as a key parameter in device design.Simulation results show that FINFETs present performance superior to conventional single gate devices. 展开更多
关键词 FINFET 3 D simulation short channel effect
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Genetic study on seed coat characteristics in multiploid watermelon 被引量:1
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作者 陈娟 《Agricultural Science & Technology》 CAS 2007年第2期13-20,共8页
[ Objective] This study is to provide basis for the genetic improvement of triploid watermelon cultivars from seed coat characteristiscs by analyzing its genetic properties. [ Method ] Genetic effects of seed coat cha... [ Objective] This study is to provide basis for the genetic improvement of triploid watermelon cultivars from seed coat characteristiscs by analyzing its genetic properties. [ Method ] Genetic effects of seed coat characteristics and their related characteristics in tdploid watermelon were analyzed by additive dominant genetic model based on 36 F1 hybrids which were crossed by six female parents of four ecotypes and six male parents of same ecotype according to North Carolina II crossing design. [ Result] The seed coat number characteristics was controlled by additive effects, dominant effects and error variance of genetic together. The additive effects of the length and width of abortive seed coat were significant, and the error variance was significant or highly significant. It was observed that there was a significant negative correlation of additive effects between the seed coat number and fringe soluble sugar. Also there was a significant negative correlation of dominant effects between lycopenes, dry matter and the seed coat number. However, there was a highly significant positive correlation in additive effects between the length and width of abortive seed coat. [ Conclusion ] The results provide guidance for genetic breeding of triploid watermelon cultivars. 展开更多
关键词 triploid watermelon seed coat characteristics genetic effect correlation analysis
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High-level Stark Effect and Spectrum of Spherical Nanometer System 被引量:1
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作者 吴强 龙晓霞 郑瑞伦 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2010年第5期608-614,622,共8页
In the electric field and layer-to-layer interaction energy, the law of split-level of high-level Stark effect of spherical nanometer system is explored as well as the frequency of spectrum, intensity and size effect ... In the electric field and layer-to-layer interaction energy, the law of split-level of high-level Stark effect of spherical nanometer system is explored as well as the frequency of spectrum, intensity and size effect of coefficient of spontaneous radiation. Taking three layers CdS/HgS spherical nanometer system as an example, the influence of the electric field and layer-to- layer interaction energy is explored on Stark effect and spectrum. The results show that in the Stark effect system, the energy level is split based on 1, 3, ..., (2n-1), when it is in the electric field only, similar to the hydrogen atoms; and in the electric field and layer-to-layer interaction, it is split based on 1, 4, ~ -., n2; with the quantum transition, the frequency of the spectrum decreases with the increasing size of the system; apart from a few spectral lines, the intensity of most spectral lines will decreased as the size increases; while the coefficient of spontaneous radiation will increase with the increasing size; the electric field will cause the changes of spectrum frequency; its spectrum frequency shift is proportional to the square of the electric field intensity; apart from a few spectral lines, the frequency shift of spectral lines that is caused by the electric field and layer-to-layer interaction will decrease as the size increases; the interaction will make the level of electronic energy level lower slightly (the order of magnitude is between 10-7-10-9 eV), the slightly increased spectrum intensity and the slightly increased value of coefficient of spontaneous radiation, but it will not influence the frequency of spectrum, intensity, and the trend that coefficient of spontaneous radiation changes with the size; when the size is smaller, the layer-to-layer interaction effect will be significant. 展开更多
关键词 Layer-to-layer interaction energy CdS/HgS/CdS spherical nanometer system Stark effect Frequency shift of spectral line Coefficient of spontaneous radiation
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Theoretical studies of CO oxidation with lattice oxygen on Co_3O_4 surfaces 被引量:2
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作者 王阳刚 杨小峰 李隽 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第1期193-198,共6页
Low-temperature CO oxidation has attracted extensive interest in heterogeneous catalysis because of the potential applications in fuel cells,air cleaning,and automotive emission reduction.In the present study,theoreti... Low-temperature CO oxidation has attracted extensive interest in heterogeneous catalysis because of the potential applications in fuel cells,air cleaning,and automotive emission reduction.In the present study,theoretical investigations have been performed using density functional theory to elucidate the crystal plane effect and structure sensitivity of Co3O4 nano-catalysts toward catalyzing CO oxidation.It is shown that the surface Co–O ion pairs are the active site for CO oxidation on the Co3O4 surface.Because of stronger CO adsorption and easier removal of lattice oxygen ions,the Co3O4(011)surface is shown to be more reactive for CO oxidation than the Co3O4(001)surface,which is consistent with previous experimental results.By comparing the reaction pathways at different sites on each surface,we have further elucidated the nature of the crystal plane effect on Co3O4 surfaces and attributed the reactivity to the surface reducibility.Our results suggest that CO oxidation catalyzed by Co3O4 nanocrystals has a strong crystal plane effect and structure sensitivity.Lowering the vacancy formation energy of the oxide surface is key for high CO oxidation reactivity. 展开更多
关键词 Carbon monoxide oxidation Cobalt oxide Crystal plane effect Ion-pair active center
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Three-dimensional forward modeling and response characteristics analysis of foundation pit leakage electric-field considering electrokinetic effect 被引量:3
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作者 Chen Yu-Feng Chen Hui +3 位作者 Deng Ju-Zhi Liu Sui-Ming Tang Wen-Wu Wang Shuo 《Applied Geophysics》 SCIE CSCD 2022年第1期117-131,146,共16页
The traditional ground direct current method is not suitable for leakage detection of underground diaphragm walls in foundation pits because of its low accuracy and poor anti-noise ability.Here,we propose a joint surf... The traditional ground direct current method is not suitable for leakage detection of underground diaphragm walls in foundation pits because of its low accuracy and poor anti-noise ability.Here,we propose a joint surface-borehole observation device for leakage electric fi eld detection to achieve rapid measurement of the electric fi eld distribution characteristics at ground level in the foundation pit,thus enabling rapid localization of leakage points.We first establish the mechanism and basic equation of the leakage electric field response by combining the electric field formed by electrokinetic effect(EK)and the stable electric fi eld formed by conduction current in a combined leakage channel.Then,the fi nite–infi nite element coupling method is used to solve the electric fi eld equation to simulate the responses of a three-dimensional foundation pit leakage model.Furthermore,we conduct numerical simulations of diff erent pit models to investigate the infl uencing factors of the detection device and response characteristics of the change in the properties of the leakage channel.The results demonstrate that the proposed joint surface-borehole observation device can effi ciently reveal anomalous potential caused by leakage,and the amplitude of the electric fi eld generated by EK can eff ectively strengthen the leakage electric fi eld signal at the leakage,thus improving detection accuracy and effi ciency. 展开更多
关键词 Foundation pit leakage 3D forward modeling Electrokinetic effect Leakage electric field
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Mutagenic effects of chromium trioxide on root tip cells of Vicia faba 被引量:8
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作者 钱晓徽 《Journal of Zhejiang University Science》 CSCD 2004年第12期1570-1576,共7页
In this study on the mutagenic effects of different concentrations of chromium trioxide (CrO3) on Vicia faba root tip, micronucleus assay and chromosome aberration assay were used to determine the mitotic indexes, mic... In this study on the mutagenic effects of different concentrations of chromium trioxide (CrO3) on Vicia faba root tip, micronucleus assay and chromosome aberration assay were used to determine the mitotic indexes, micronucleus rate and chromosome aberration rate of Vicia faba root tip cells. The results showed that the effects of CrO3 concentration on the mitotic indexes were complicated. CrO3 increases the micronucleus rate of Vicia faba root tip cells. It was found that within certain range of CrO3 concentration the micronucleus rate increased systematically with increased concentration of CrO3, but that the micronucleus rate decreased at higher level of CrO3 and that CrO3 also caused various types of chromosome aberration at a rate which increased systematically with increased concentration of CrO3. We concluded that CrO3 has significant mutagenic effect on Vicia faba root tip cells. 展开更多
关键词 Chromium trioxide (CrO3) VICIAFABA Mitotic index Micronucleus rate Rate of chromosome aberration
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A Novel Initiator Containing Alkyne Group for the Polymerization of 2-Ethyl-2-oxazoline
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作者 Muhammad Waqas Ali 高亚婷 +1 位作者 Muhammad Siddiq 叶晓东 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 2018年第1期77-84,I0002,共9页
A novel trifunctional initiator with one alkyne and two trifluoromethanesulfonate moieties was synthesized from a protected alcohol 5-hydroxyl-2-phenyl-1, 3-dioxane. The alkyne func- tionalized intermediate with two p... A novel trifunctional initiator with one alkyne and two trifluoromethanesulfonate moieties was synthesized from a protected alcohol 5-hydroxyl-2-phenyl-1, 3-dioxane. The alkyne func- tionalized intermediate with two protected alcohol groups was synthesized by reacting with propargyl bromide. The alcohol groups were cleaved using a mixture of tetrahydrofuran and hydrochloric acid aqueous solution. In the last step the initiator was synthesized us- ing triflic anhydride in carbon tetrachloride. The initiator was characterized by 1H NMR and used for the polymerization of 2-ethyl-2-oxazoline which gives polymers with narrow distribution. For comparison a similar initiator with two tosylates was prepared and used for the polymerization of the monomer 2-ethyl-2-oxazoline, the resulting product has a wide molecular weight distribution and most of the initiator remains unreacted after 24 h which may be due to the steric hindrance between the two tosylate groups. To further explore the steric hindrance phenomenon, a linear tosylate initiator was synthesized, but still some of the initiator remains unreacted, illustrating that both steric hindrance and electrophilic balance affect the efficiency of the cationic ring-opening polymerization. All of the polymers were characterized in detail by using IH NMR, matrix-assisted laser desorption/ionization time-of-flight mass spectroscopy, and size exclusion chromatography to confirm the purity and distribution of the polymers. 展开更多
关键词 ELECTROPHILE 2-Ethyl-2-oxazoline Steric hindrance TRIFLATE
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Preparation and characterization of ferromagnetic fluids for hyperthermia of tumor
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作者 周彦菲 范田园 +2 位作者 杨仁杰 孙宏亮 夏启胜 《Journal of Chinese Pharmaceutical Sciences》 CAS 2007年第3期187-191,共5页
Aim To prepare and characterize ferromagnetic fluids for hyperthermia of tumor. Methods Ferromagnetic fluids (FFs) of magnetite (Fe3O4) was prepared in the presence of polyethylene glycol (PEG-6000) by chemical ... Aim To prepare and characterize ferromagnetic fluids for hyperthermia of tumor. Methods Ferromagnetic fluids (FFs) of magnetite (Fe3O4) was prepared in the presence of polyethylene glycol (PEG-6000) by chemical precipitation method. The iron content of the FFs was determined by spectrophotometric method using o-phenanthroline. The FFs/PEG-6000 was characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), infrared spectrometry (IR), and vibrating sample magnetometer (VSM). Heating effects of the FFs was measured in an alternating magnetic field in vitro. The hyperthermia of FFs in a rabbit was performed. Results The FFs/PEG-6000 was proved to be composed of Fe3O4 by XRD and IR. TEM showed that the ferromagnetic particles appeared to be almost spherical and dispersed well The average particle size was 13.3 ± 3.8 nm by XRD. The saturation magnetization and residual magnetization of the FFs were 23.39 A/m (1.556 emu/g) and 0.56 A/m (0.02604 emu/g), respectively. The coercive force was 12 Oe. The specific absorption rate (SAR) of FFs was 69 ± 10W/g [Fe]. After direct injection of FFs to hepatic VX2 carcinoma of a rabbit, the temperature in the core of the tumor was between 41 - 46 ℃ in an alternating magnetic field. Conclusion FFs/PEG-6000 was expected to be useful in hyperthermia of tumor. 展开更多
关键词 Ferromagnetic fluids FE3O4 Polyethylene glycol (PEG) Heating effects HYPERTHERMIA
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Joint effects of microwave and chromium trioxide on root tip cells of Vicia faba 被引量:1
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作者 QIAN Xiao-wei LUO Wei-hua ZHENG Ou-xiang 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2006年第3期221-227,共7页
The mutagemc effects of microwave and chromium trioxide (CrO3) on Vicia faba root tip were studied. Micronucleus assay and chromosomal aberration assay were used to determine the mitotic index, the micronucleus freq... The mutagemc effects of microwave and chromium trioxide (CrO3) on Vicia faba root tip were studied. Micronucleus assay and chromosomal aberration assay were used to determine the mitotic index, the micronucleus frequency and chromosomal aberration frequency of Vicia faba root tip cells induced by microwave and CrO3. The results showed that the micronucleus frequency decreased, and that the mitotic index and chromosomal aberration frequency showed linear dose responses to CrO3, in treatment of microwave for 5 s. In microwave of 25 s, the mitotic index decreased, the micronucleus frequency and chromosomal aberration frequency increased with increase of CrO3 concentration. We concluded that microwave and CrO3 had antagonistic effect on the mitotic index of Vicia faba root tip cells, but had synergetic effect on micronucleus frequency and chromosomal aberration frequency of Viciafaba root tip cells. 展开更多
关键词 MICROWAVE Chromium trioxide (CrO3) Antagonistic effect Synergetic effect
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Urbanization effect on precipitation over the Pearl River Delta based on CMORPH data 被引量:6
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作者 CHEN Sheng LI Wei-Biao +2 位作者 DU Yao-Dong MAO Cheng-Yan ZHANG Lan 《Advances in Climate Change Research》 SCIE CSCD 2015年第1期16-22,共7页
Based on the satellite data from the Climate Prediction Center morphing(CMORPH) at very high spatial and temporal resolution, the effects of urbanization on precipitation were assessed over the Pearl River Delta(PRD) ... Based on the satellite data from the Climate Prediction Center morphing(CMORPH) at very high spatial and temporal resolution, the effects of urbanization on precipitation were assessed over the Pearl River Delta(PRD) metropolitan regions of China. CMORPH data well estimates the precipitation features over the PRD. Compared to the surrounding rural areas, the PRD urban areas experience fewer and shorter precipitation events with a lower precipitation frequency(ratio of rainy hours, about 3 days per year less); however, short-duration heavy rain events play a more significant role over the PRD urban areas. Afternoon precipitation is much more pronounced over the PRD urban areas than the surrounding rural areas, which is probably because of the increase in short-duration heavy rain over urban areas. 展开更多
关键词 CMORPH Urbanization effects Pearl River Delta
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Dynamic characteristics of high stressed red sandstone subjected to unloading and impact loads 被引量:11
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作者 GONG Feng-qiang ZHONG Wen-hui +2 位作者 GAO Ming-zhong SI Xue-feng WU Wu-xing 《Journal of Central South University》 SCIE EI CAS CSCD 2022年第2期596-610,共15页
In the process of deep projects excavation,deep rock often experiences a full stress process from high stress to unloading and then to impact disturbance failure.To study the dynamic characteristics of three-dimension... In the process of deep projects excavation,deep rock often experiences a full stress process from high stress to unloading and then to impact disturbance failure.To study the dynamic characteristics of three-dimensional high stressed red sandstone subjected to unloading and impact loads,impact compression tests were conducted on red sandstone under confining pressure unloading conditions using a modified split Hopkinson pressure bar.Impact disturbance tests of uniaxial pre-stressed rock were also conducted(without considering confining pressure unloading effect).The results demonstrate that the impact compression strength of red sandstone shows an obvious strain rate effect.With an approximately equal strain rate,the dynamic strength of red sandstone under confining unloading conditions is less than that in the uniaxial pre-stressed impact compression test.Confining pressure unloading produces a strength-weakening effect,and the dynamic strength weakening factor(DSWF)is also defined.The results also indicate that the strain rate of the rock and the incident energy change in a logarithmic relation.With similar incident energies,unloading results in a higher strain rate in pre-stressed rock.According to the experimental analysis,unloading does not affect the failure mode,but reduces the dynamic strength of pre-stressed rock.The influence of confining pressure unloading on the shear strength parameters(cohesion and friction angle)is discussed.Under the same external energy impact compression,prestressed rock subjected to unloading is more likely to be destroyed.Thus,the effect of unloading on the rock mechanical characteristics should be considered in deep rock project excavation design. 展开更多
关键词 deep rock excavation unloading unloading confining pressure three-dimensional high stress strengthweakening effect impact disturbance
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Three—Body Force Effects on EOS of Asymmetric Nuclear Matter and Proton Fraction in Neutron Star Matter
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作者 ZUOWei A.Lejeune +1 位作者 U.Lombardo J.F.Mathiot 《Communications in Theoretical Physics》 SCIE CAS CSCD 2003年第4期439-446,共8页
The three-body force effects on the equation of state and its iso-spin dependence of asymmetric nuclear matter and on the proton fraction in neutron star matter have been investigated within Brueckner-Hartree-Fock app... The three-body force effects on the equation of state and its iso-spin dependence of asymmetric nuclear matter and on the proton fraction in neutron star matter have been investigated within Brueckner-Hartree-Fock approach by using a microscopic three-body force. It is shown that, even in the presence of the three-body force, the empirical parabolic law of the energy per nucleon vs. isospin asymmetry is fulfilled in the whole asymmetry range and also up to high density. The three-body force provides a strong enhancement of symmetry energy at high density in agreement with relativistic approaches. It also shows that the three-body force leads to a much more rapid increasing of symmetry energy with density in relatively high density region and to a much lower threshold density for the direct URCA process to occur in a neutron star as compared to the predictions adopting only pure two-body force. 展开更多
关键词 three-body force asymmetric nuclear matter ISOSPIN
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Effects of Four Kinds of Triazine Herbicides on the Photoquenching Degradation of Acetochlor 被引量:1
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作者 黄强 张海松 《Agricultural Science & Technology》 CAS 2014年第1期91-93,115,共4页
Effects of four kinds of triazine herbicides on the photodegradation of acetochlor were studied on glass surface and in aqueous solution under three kinds of light sources, i.e., xenon lamp, high pressure mercury lamp... Effects of four kinds of triazine herbicides on the photodegradation of acetochlor were studied on glass surface and in aqueous solution under three kinds of light sources, i.e., xenon lamp, high pressure mercury lamp and natural sunlight. The results indicated that atrazine, simetryne, prometryne and ametryne exhibited significant effects on the photoquenching degradation of acetochlor, and there was an obvious positive correlation between their effects and the dosage of four kinds of triazine herbicides. 展开更多
关键词 ACETOCHLOR Triazine herbicides Photoquenching degradation WATER Glass surface
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