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危险化学品泄漏扩散模型的研究现状分析与比较 被引量:39
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作者 孙莉 赵颖 +1 位作者 曹飞 叶铭 《中国安全科学学报》 CAS CSCD 北大核心 2011年第1期37-42,共6页
为了对危险化学品港口装卸过程中泄漏危险度进行量化评定,基于泄漏扩散模型提高港口的应急处理技术,对危险化学品泄漏扩散模型的研究现状从理论研究、试验研究、应用研究3方面进行深入分析。着重对高斯模型(Gaussian model),BM模型,Sut... 为了对危险化学品港口装卸过程中泄漏危险度进行量化评定,基于泄漏扩散模型提高港口的应急处理技术,对危险化学品泄漏扩散模型的研究现状从理论研究、试验研究、应用研究3方面进行深入分析。着重对高斯模型(Gaussian model),BM模型,Sutton模型,FEM3模型,箱及相似模型,P-G模型等模型从理论描述方法、适用对象和范围、计算精度和难易、参数选取等方面进行优缺点的对比研究,认为:由于危险化学品泄漏和扩散行为的复杂性,影响因素的多样性,使各类模型在具备一定的理论价值和现实意义的同时,还存在着参数选取不确定性、试验模拟差异性以及实际应用局限性的问题和不足,运用计算机技术完善试验结果数据库、改进数学仿真模型是其进一步研究发展的趋势。 展开更多
关键词 危险化学品 泄漏 扩散 模型 比较
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LNG泄露后果的预测模型 被引量:20
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作者 彭世尼 段萍 《重庆大学学报(自然科学版)》 EI CAS CSCD 北大核心 2006年第1期93-97,共5页
液化天然气(LNG)在全球的贸易额正在逐年增长,尤其是在中国能源进口贸易中已经成为继石油之后的主要能源产品,对于它的安全使用问题已经变得非常重要.针对LNG储存以及运输过程中可能导致的泄漏问题以及相关的安全问题,采用了计算流体力... 液化天然气(LNG)在全球的贸易额正在逐年增长,尤其是在中国能源进口贸易中已经成为继石油之后的主要能源产品,对于它的安全使用问题已经变得非常重要.针对LNG储存以及运输过程中可能导致的泄漏问题以及相关的安全问题,采用了计算流体力学为基础的计算机模型MTB,DE-GAD IS,FEM3A,并使用小规模的物理实验对模型进行检验,以达到精确和经济的预测结果.解决了传统实地物理模拟费用高昂,参数又难以控制的问题.在对物理模拟的难点进行了总结的基础上,提出了解决方案———超低速(ULS)风洞实验,并用于新一代的预测模型FEM3A的研究,以及预测模型的发展方向和实现方法———获得更高次的紊流闭合模型,并不断利用物理模拟对其进行检验修正. 展开更多
关键词 液化天然气 泄漏 模型 风洞 CFD DEGADIS FEM3A
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Artificial enhancement of sturgeon stock in freshwater reservoirs:A case study on sterlet Acipenser ruthenus of the Kama reservoir
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作者 Pavel B.Mikheev Semyon N.Kazarinov +5 位作者 Alla G.Melnikova Stanislav V.Ponosov Nikolai G.Petrenko Andrei I.Nikiforov Alexey Yu Puzik Olga N.Elchenkova 《Aquaculture and Fisheries》 CSCD 2024年第2期287-294,共8页
The paper presents the results of the sterlet sturgeon Acipenser ruthenus reintroduction into the Kama Reservoir(Perm Krai,Russia)by sterlet fry from hatcheries into the reservoir since 2001.The effectiveness of hatch... The paper presents the results of the sterlet sturgeon Acipenser ruthenus reintroduction into the Kama Reservoir(Perm Krai,Russia)by sterlet fry from hatcheries into the reservoir since 2001.The effectiveness of hatchery releases was evaluated by monitoring gillnet sampling 2014-2020.The results showed that the species was reported throughout entire Kama Reservoir,which contrasts with 1988-1994 data,when the species was registered only at the upper part of the reservoir near the Kama River mouth.The highest number and biomass values of catch per unit effort(CPUE)of the sterlet were found in submerged river channels-the deepest habitats with flow conditions which are close to the ecological requirements of the species.The distribution of the sterlet within the channel biotopes of the reservoir is defined by reduced variability.The biggest individuals and the widest size range of the sterlet were typical for the upper area of the reservoir and Chusovskoy Bay,which have the greatest flow.The smallest sizes were typical for fish from catches near the dam of the reservoir,which is consistent with the published data on the distribution of sterlet in reservoir conditions.The presented results may indicate the artificial formation of the sterlet stock in the Kama Reservoir maintained by hatchery releases.The revealed distribution of the sterlet in the reservoir determines the direction of further research on natural reproduction and thus formation of an artificially formed population.Also,future studies are required to assess the possibility of hybridization of the sterlet of artificial origin with natural populations of the species,since the low genetic diversity of the sterlet released into the Kama Reservoir which can lead to irreversible loss of genetic individuality of the natural stocks of the species in the catchment of upper course of the Kama River. 展开更多
关键词 Sterlet Acipenser ruthenus Kama reservoir Hatchery releases CPUE Artificial stock formation
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核电站氚的排放量及浓度限值比较分析 被引量:6
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作者 乔亚华 王亮 +1 位作者 叶远虑 刘福东 《核科学与工程》 CSCD 北大核心 2017年第3期434-441,共8页
氚是核电站运行过程中向环境中排放较大的放射性核素之一,控制核设施中氚的产生和排放量越来越引起人们的重视。本文通过分析核电站产生氚的主要途径,结合国际上的运行经验参数,对比分析了不同国家、不同堆型核电站氚的排放量和浓度限... 氚是核电站运行过程中向环境中排放较大的放射性核素之一,控制核设施中氚的产生和排放量越来越引起人们的重视。本文通过分析核电站产生氚的主要途径,结合国际上的运行经验参数,对比分析了不同国家、不同堆型核电站氚的排放量和浓度限值。分析结果表明:三十年间,全球核电站流出物中气态氚的排放量显著高于液态氚,重水堆是各堆型核电站中氚排放的主要贡献者,也是氚排放所致公众剂量的主要来源。为了更加有效的控制氚的排放,法国等国家核安全监管机构根据电站的装机容量、排放工艺、堆型等制定了各自国家核电站氚的年排放总量限值;加拿大等国的监管机构根据剂量限值制定了导出排放限值,该值的优点是便于审查核电站正常运行时氚的排放量;其它核电国家则是以剂量限值的形式提出了氚的排放限值。 展开更多
关键词 核电站 排放量 限值
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Radio Wave Propagation Effects Produced by Chemical Releases in the Ionosphere 被引量:3
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作者 HU Yaogai ZHAO Zhengyu XIANG Wei 《Wuhan University Journal of Natural Sciences》 CAS 2011年第3期249-254,共6页
As an effective means to actively modify the ionosphere, chemical release can produce artificial ionospheric holes as a consequence of ionization depletion, which can greatly impact on radio wave propagation. In this ... As an effective means to actively modify the ionosphere, chemical release can produce artificial ionospheric holes as a consequence of ionization depletion, which can greatly impact on radio wave propagation. In this paper, on the basis of the pre-study results on ionospheric disturbances produced by some representative chemical releases, the radio waves propagation effects of ionospheric holes that are produced by two different release species, water (H2O) and sulfur hexafluoride (SF6), had been investigated and simulated by the three-dimensional (3-D) numerical ray tracing. The results show that 1 the appearance of various artificial ionospheric holes can lead to certain decrease of critical frequency in the ionosphere, and 2 when the wave frequency exceeds the critical frequency, the rays should be multiple reflections or penetrate through the ionospheric hole and focus afterwards with the focus altitude elevated for higher frequencies. This work may provide the necessary theoretical support for chemical release experiments and the evaluation of radio wave propagation effects. 展开更多
关键词 chemical releases ionospheric hole ray tracing radio wave propagation
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The identification of individuals with hatchery and natural origin in a mixed sample of Amur River chum salmon by Otolith microchemistry 被引量:1
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作者 Pavel B.Mikheev Denis V.Kotsyuk +5 位作者 Elena V.Podorozhnyuk Vsesolod N.Koshelev Atbkyh I.Nikiforov Tatiana A.Sheina Alexey Yu.Puzik Mikhail A.Baklanov 《Aquaculture and Fisheries》 CSCD 2023年第3期341-350,共10页
We estimated the proportion of hatchery and natural fall spawning chum salmon returning to the Amur River using chemical markers specific to hatchery-origin fry.We used otolith microchemistry technique to identify fis... We estimated the proportion of hatchery and natural fall spawning chum salmon returning to the Amur River using chemical markers specific to hatchery-origin fry.We used otolith microchemistry technique to identify fish with artificial origin among returning spawners.First,we found that juveniles of artificial origin had higher values of the Sr:Ca molar ratio of the otoliths’edge zone compared with juveniles of natural origin,what can be related to the use of rearing feed produced from raw materials of marine origin rich in strontium.Then we observed that most of the spawners from Anyuisky Hatchery and from the Amur River mouth at the start of the spawning migration has also the higher value of Sr:Ca molar ratio of the juvenile zone of otoliths.Also,adults with higher values of the Sr:Ca molar ratio are characterized by a skewed right in the peak of the age distribution.Both,the age structure and phenological shift in the time of spawning migration of individuals with higher value of the used chemical marker corresponds to results of studies on hatchery-produced chum salmon completed at different parts on Northern Pacific.The results of this study will be used in the management of Amur fall chum salmon fisheries,and also demonstrates the necessity of the development of specific measures for increasing the survival of juvenile anadromous salmonids released at large rivers and exposed to prolonged freshwater migration to the ocean.As a further application of the methodology,we plan to identify the markers specific to each of the hatcheries and main spawning tributaries belonging to Amur River catchments.This will be an important step in the evaluation of the contribution of different stocks in mixed fisheries and also in the estimation of the effect of hatchery releases on naturally spawning stocks of Amur fall chum.Following to,our results may indicate the applicability of this approach for the determination of artificial-origin fish in a mixed sample of the Amur fall chum salmon. 展开更多
关键词 Otolith microchemistry LA ICP-MS Chum salmon Identification of origin in a mixed sample Hatchery releases
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生物炭释出物的效应及其缓解策略与应用
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作者 岳美如 胡佳俊 +2 位作者 高旻天 李继香 刘楠 《上海大学学报(自然科学版)》 CAS CSCD 北大核心 2023年第6期1003-1021,共19页
生物炭具有比表面积高、表面官能团丰富、结构稳定、低成本及原料来源于可再生生物质等特性,被广泛应用于环境修复领域.然而,现有研究多集中于生物炭的理化性质与功能,而有关生物炭释出物的研究较少.本工作详细分析了生物炭释出物的正... 生物炭具有比表面积高、表面官能团丰富、结构稳定、低成本及原料来源于可再生生物质等特性,被广泛应用于环境修复领域.然而,现有研究多集中于生物炭的理化性质与功能,而有关生物炭释出物的研究较少.本工作详细分析了生物炭释出物的正负面效应,罗列了减少生物炭可溶性释出物的方法,并例举了低释出生物炭的现有应用.本工作为后续低释出生物炭的制备、改良与应用提供了可借鉴的方法与思路. 展开更多
关键词 生物炭 释出物 可再生生物质 改性 环境修复
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An experimental study on oil droplet size distribution in subsurface oil releases 被引量:1
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作者 LI Jianwei AN Wei +2 位作者 GAO Huiwang ZHAO Yupeng SUN Yonggen 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2018年第11期88-95,共8页
Oil droplet size distribution (ODSD) plays a critical role in the rising velocity and transport of oil droplets in subsurface oil releases. In this paper, subsurface oil release experiments were conducted to study O... Oil droplet size distribution (ODSD) plays a critical role in the rising velocity and transport of oil droplets in subsurface oil releases. In this paper, subsurface oil release experiments were conducted to study ODSD under different experimental conditions in a laboratory water tank observed by two high-speed cameras in March and April 2017. The correlation formulas Oh=lO.2Re-~ and Oh=39.2Re-1 (Re represents Reynolds number and Oh represents Ohnesorge number) were established to distinguish the boundaries of the three instability regimes in dimensionless space based on the experimental results. The oil droplet sizes from the experimental data showed an excellent match to the Rosin-Rammler distribution function with determination coefficients ranging from 0.86 to 1.00 for Lvda 10-1 oil. This paper also explored the influence factors on and change rules ofoil droplet size. The volume median diameter d50 decreased steadily with increasing jet velocity, and a sharp decrease occurred in the laminar-breakup regime. At Weber numbers (We) 〈100, the orifice diameter and oil viscosity appeared to have a large influence on the mean droplet diameter. At 100〈We〈1 000, the oil viscosity appeared to have a larger influence on the relative mean droplet diameter. 展开更多
关键词 oil droplet size distribution subsurface oil releases Rosin-Rammler distribution
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Modeling the Flow Regime Near the Source in Underwater Gas Releases 被引量:2
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作者 Lakshitha T. Premathilake Poojitha D. Yapa +1 位作者 Indrajith D. Nissanka Pubudu Kumarage 《Journal of Marine Science and Application》 CSCD 2016年第4期433-441,共9页
Recent progress in calculating gas bubble sizes in a plume, based on phenomenological approaches using the release conditions is a significant improvement to make the gas plume models self-reliant. Such calculations r... Recent progress in calculating gas bubble sizes in a plume, based on phenomenological approaches using the release conditions is a significant improvement to make the gas plume models self-reliant. Such calculations require details of conditions Near the Source of Plume (NSP); (i.e. the plume/jet velocity and radius near the source), which inspired the present work. Determining NSP conditions for gas plumes are far more complex than that for oil plumes due to the substantial density difference between gas and water. To calculate NSP conditions, modeling the early stage of the plume is important. A novel method of modeling the early stage of an underwater gas release is presented here. Major impact of the present work is to define the correct NSP conditions for underwater gas releases, which is not possible with available methods as those techniques are not based on the physics of flow region near the source of the plume/jet. We introduce super Gaussian profiles to model the density and velocity variations of the early stages of plume, coupled with the laws of fluid mechanics to define profile parameters. This new approach, models the velocity profile variation from near uniform, across the section at the release point to Gaussian some distance away. The comparisons show that experimental data agrees well with the computations. 展开更多
关键词 underwater gas releases bubble plumes near source conditions plumes/jets oil and gas spill models
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中国传统体育文化特征的神话阐释 被引量:1
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作者 蔡艺 《湖南科技学院学报》 2005年第11期275-276,共2页
神话作为民族文化的结晶,其蕴含的民族精神与文化性格势必会深深烙刻在各民族的体育丈化上。通过对中国神话“人兽共体”的外形、“重德尚和”的价值观、“天人合一”的自然观特点的分析,合理地阐释了中国传统体育存在仿生性、道德性、... 神话作为民族文化的结晶,其蕴含的民族精神与文化性格势必会深深烙刻在各民族的体育丈化上。通过对中国神话“人兽共体”的外形、“重德尚和”的价值观、“天人合一”的自然观特点的分析,合理地阐释了中国传统体育存在仿生性、道德性、中庸性和整体性特征的原因。 展开更多
关键词 中国 体育文化 神话 阐释
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Radiation dose rate estimates to marine biota resulting from the routine radioactive releases of the nuclear power plants in Daya Bay
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作者 Wenqiao Tang Ziqiang Pan +1 位作者 Yihua Xia Xiwen Jiang 《Chinese Science Bulletin》 SCIE EI CAS 1999年第22期2063-2067,共5页
Five marine organisms in Daya Bay are selected for estimating the dose rates. Internal exposure and its 5 pathways are also considered. The concentrations of 43 kinds of background and additional radionuclides in seaw... Five marine organisms in Daya Bay are selected for estimating the dose rates. Internal exposure and its 5 pathways are also considered. The concentrations of 43 kinds of background and additional radionuclides in seawater are from the survey of background radioactivity and the prediction of routine radioactive releases of the 4 reactors. Point source dose distribution functions are used to estimate the dose rates to various organisms from a and β radiation. 展开更多
关键词 nuclear power plants ROUTINE liquid RADIOACTIVE releases RADIATION dose rate MARINE BIOTA DAYA Bay.
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Yield Estimation for a Single Purpose Multi-Reservoir System Using LP Based Yield Model
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作者 Deepak V. Pattewar Kalpeshkumar M. Sharma P. D. Dahe 《Journal of Water Resource and Protection》 2013年第7期28-34,共7页
Application of optimization techniques for determining the optimal operation policy for reservoir is a major area in water resources planning and management. Linear programming, ruled by evolution techniques, has beco... Application of optimization techniques for determining the optimal operation policy for reservoir is a major area in water resources planning and management. Linear programming, ruled by evolution techniques, has become popular for solving optimization problems in diversified fields of science. An LP-based yield model (YM) has been used to reevaluate the annual yield available from the reservoirs for irrigation. This paper extends the basic yield model and presents a yield model for a multiple-reservoir system consisting of single-purpose reservoirs. Optimum yield of reservoirs system is calculated by yield model. The objective is to achieve prespecified reliability for irrigation and to incorporate an allowable deficit in the annual irrigation target. The yield model is applied to a system of two reservoirs in theManarRiverinIndia. This model can act as a better screening tool in planning by providing outputs that can be very useful in improving the efficiency and accuracy of detailed analysis methods such as simulation. 展开更多
关键词 Yield Model RESERVOIR Operation IRRIGATION releases Manar River
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Hainan Province Becomes a Free Trade Area: China Releases a Heavy Signal of Reform and Opening-up
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作者 Zhang Lin 《Peace》 2018年第2期14-15,共2页
Choosing an important occasion to announce the decision to build Hainan Province a FTA has further released the important signal that China is heading towards the new stage of opening-up.On April 13th,2018,Xi Jinping,... Choosing an important occasion to announce the decision to build Hainan Province a FTA has further released the important signal that China is heading towards the new stage of opening-up.On April 13th,2018,Xi Jinping,General Secretary of the Central Committee of the Communist Party of China(CPC)and President of China,solemnly announced at the conference in celebrating the 30th anniversary of the Hainan Province-run Special Economic Zone that the CPC Central Committee decides to support the construction of a pilot free trade area on the whole island of Hainan province. 展开更多
关键词 China releases a HEAVY SIGNAL of REFORM and Opening-up HAINAN Province BECOMES a Free TRADE Area
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Cleavable bimetallic-organic polymers for ROS mediated cascaded cancer therapy under the guidance of MRI through tumor hypoxia relief strategy
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作者 Haozhe He Lihua Du +9 位作者 Min Tan Yali Chen Liejing Lu Yongcheng An Yong Wang Xiaoxia Li Bo Li Jun Shen Jun Wu Xintao Shuai 《Science China Chemistry》 SCIE EI CAS CSCD 2020年第7期936-945,共10页
Despite recent advances in tumor treatment, reactive oxygen species(ROS)-mediated therapy, such as photodynamic therapy(PDT) and chemical dynamic therapy(CDT), remains challenging mainly due to hypoxia in tumor microe... Despite recent advances in tumor treatment, reactive oxygen species(ROS)-mediated therapy, such as photodynamic therapy(PDT) and chemical dynamic therapy(CDT), remains challenging mainly due to hypoxia in tumor microenviroment. Relieving the hypoxia of tumor tissue has been considered as an attractive strategy for enhancing efficacy of ROS-based cancer treatment.Herein, one cascaded platform was developed to overcome tumor hypoxia and synergistically enhance the effect of ROSmediated therapy. This platform is based on cleavable bimetallic metal organic polymers(DOX@Fe/Mn-THPPTK-PEG). As an efficient Fenton-like material, it could not only produce cytotoxic ·OH by catalyzing the decomposition of intracellular H2O2, but also generate O2 to alleviate tumor hypoxia. In addition, the DOX-loaded metal organic polymers(MOPs could be disrupted after being exposed to laser irradiation or/and treated with H2O2, and then release the DOX for chemotherapy. Overall, 3 therapies(hypoxia-relieved PDT, photo-enhanced CDT, and ROS-mediated chemotherapy) could be achieved simultaneously by such a smart platform. Furthermore, T1-weighted MRI imaging ability of the MOPs could be greatly improved under H2O2 treatment.Therefore, total four robust functions were realized in a simple platform. These findings demonstrate great clinical potentials of the MOPs for cancer theranostics. 展开更多
关键词 reactive oxygen species photodynamic therapy chemodynamic therapy ROS sensitive drug releases MRI imaging
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in FASH Releases Color Trends for A/W 10/11 & S/S 2011
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《China Textile》 2009年第9期16-17,共2页
Color trend insights extremely benefit textile and fashion industries What is the next big Trend? This is not just the question to get dressed in trend. But trends information is highly essential for designers
关键词 in FASH releases Color Trends for A/W 10/11 S/S 2011
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祁连山多年冻土区天然气水合物的形成条件 被引量:79
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作者 祝有海 刘亚玲 张永勤 《地质通报》 CAS CSCD 北大核心 2006年第1期58-63,共6页
祁连山多年冻土区面积约10×104km2,年平均地表地温为-1.5~-2.4℃,冻土层厚度为50~139m。区内侏罗纪小型含煤盆地广布,产有丰富的煤层气。南祁连盆地是一潜在的油气盆地,存在下石炭统臭牛沟组、下二叠统草地沟组、中三叠统大加连... 祁连山多年冻土区面积约10×104km2,年平均地表地温为-1.5~-2.4℃,冻土层厚度为50~139m。区内侏罗纪小型含煤盆地广布,产有丰富的煤层气。南祁连盆地是一潜在的油气盆地,存在下石炭统臭牛沟组、下二叠统草地沟组、中三叠统大加连组、上三叠统尕勒得寺组4套烃源岩,具有良好的生油生气潜力。在木里煤田33号钻孔的冻土层内发现有连续逸出的高含量烃类气体,井口点燃即可燃烧,简易采气分析结果表明甲烷含量高达38.07%~75.9%。根据该钻孔的气体组分、年平均地表地温、冻土层厚度、地温梯度等数据分析,这里基本具备形成天然气水合物的温压条件,计算结果显示水合物稳定带的顶界和底界埋深分别为171m和574m,稳定带厚度为403m。 展开更多
关键词 天然气水合物 冻土 气体漏泄 水合物稳定带 祁连山
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白洋淀生态需水:进展及展望 被引量:28
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作者 杨薇 赵彦伟 +1 位作者 刘强 孙涛 《湖泊科学》 EI CAS CSCD 北大核心 2020年第2期294-308,共15页
采用文献计量、统计分析等手段收集了国内外关于白洋淀生态需水核算的研究成果,系统梳理了15种白洋淀生态需水核算方法,获得了白洋淀不同时间尺度、不同等级生态需水核算结果,并结合雄安新区规划对白洋淀生态需水核算存在的问题及未来... 采用文献计量、统计分析等手段收集了国内外关于白洋淀生态需水核算的研究成果,系统梳理了15种白洋淀生态需水核算方法,获得了白洋淀不同时间尺度、不同等级生态需水核算结果,并结合雄安新区规划对白洋淀生态需水核算存在的问题及未来的需求提出了展望.统计结果表明,白洋淀最小生态水位为7.45±0.66 m,适宜水位为8.61±0.52 m,最大水位为9.46±0.51 m;各等级生态需水月际变化趋势大致相同,89月最大,5月最小,但各月不同等级生态需水量的变幅较大;白洋淀最小生态补水量为1.35亿m^3,适宜补水量2.40亿m^3,最大生态补水量6.20亿m^3.从支撑雄安新区规划建设的角度来看,目前白洋淀生态需水核算中面临的不足主要集中在生态管理目标和方法选择导致核算结果差异较大、缺乏淀区生态需水机制的阐释、生态需水核算时间尺度较粗略、未考虑淀区空间异质性的需水差异以及忽略河湖水文连通关系与过程5个方面;最后,以恢复白洋淀良性生态系统为导向,从分级分区开展白洋淀生态需水精细核算、分时分段淀区生态需水量质耦合模拟和考虑河湖沼连通的淀区水动力过程恢复3个方面提出了未来研究的建议与展望. 展开更多
关键词 白洋淀 生态需水 流量调控 生态补水 雄安新区
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化学物质释放人工改变电离层 被引量:18
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作者 黄文耿 古士芬 《空间科学学报》 CAS CSCD 北大核心 2005年第4期254-258,共5页
考虑中性气体在电离层高度的扩散过程和相应的电离层离子化学过程,研究了利用主动化学物质释放来改变电离层的方法,理论计算了H2O和SF6两种气体释放后电离层随时间的响应过程.结果表明,在电离层高度上气体的扩散过程非常迅速,电离层F区... 考虑中性气体在电离层高度的扩散过程和相应的电离层离子化学过程,研究了利用主动化学物质释放来改变电离层的方法,理论计算了H2O和SF6两种气体释放后电离层随时间的响应过程.结果表明,在电离层高度上气体的扩散过程非常迅速,电离层F区的电子密度有很大程度的减少,而扩散慢且化学反应快的气体对电离层的影响更大,就更加有利于电离层洞的形成. 展开更多
关键词 化学释放 电离层扰动 扩散过程
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几种典型化学物质的电离层释放效应研究 被引量:18
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作者 胡耀垓 赵正予 张援农 《物理学报》 SCIE EI CAS CSCD 北大核心 2010年第11期8293-8303,共11页
建立了一个包括中性释放气体扩散、离子化学反应及等离子体扩散等过程的化学物质电离层释放三维动力学模型,基于该模型构建了化学物质释放数值模拟软件平台,对H2O,CO2,H2和SF6等几种典型化学物质的电离层释放进行了数值模拟,给出了这些... 建立了一个包括中性释放气体扩散、离子化学反应及等离子体扩散等过程的化学物质电离层释放三维动力学模型,基于该模型构建了化学物质释放数值模拟软件平台,对H2O,CO2,H2和SF6等几种典型化学物质的电离层释放进行了数值模拟,给出了这些物质在电离层释放后产生的扰动特性和释放区域主要粒子的时空变化规律. 展开更多
关键词 典型化学物质释放 三维动力学模型 电离层扰动效应
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利用长毛钝绥螨控制冬瓜上二斑叶螨研究 被引量:10
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作者 候爱平 张艳璇 +2 位作者 杨孝泉 陈宇航 陈浩然 《昆虫天敌》 CSCD 1996年第1期29-34,共6页
冬瓜是南方主要蔬菜品种之一,遭受二斑叶螨Tetranycnusurticae(Koch)严重危害。作者在冬瓜生长五叶期每株释放长毛钝绥螨Amblyseiuslongispinosus30只,1周后二斑叶螨下降91.5%。并能控制叶螨的增殖直至收获期。室内对长毛钝绥螨... 冬瓜是南方主要蔬菜品种之一,遭受二斑叶螨Tetranycnusurticae(Koch)严重危害。作者在冬瓜生长五叶期每株释放长毛钝绥螨Amblyseiuslongispinosus30只,1周后二斑叶螨下降91.5%。并能控制叶螨的增殖直至收获期。室内对长毛钝绥螨与二斑叶螨间的相互关系进行探讨。研究表明;长毛钝绥螨对二斑叶螨的捕食功能反应属HollingⅡ型。其数学模型: 展开更多
关键词 冬瓜 长毛钝绥螨 天敌 二斑叶螨 生物防治
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