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西部开发中生态环境的保护和建设

四川师范大学学报（自然科学版） 2001年第2期24卷 192-196页

作者：张果冉茂玉四川师范大学地理系四川成都610066

针对西部生态环境的现状 ,运用生态系统、可持续发展以及环境保护等理论 ,强调西部开发中生态环境的保护和对生态脆弱部分加大建设治理力度。

关键词：西部开发生态环境环境保护可持续发展生态系统生态建设生态平衡

Study on Nitrogen and Phosphorus Export from Sloping Cropland of Purple Soil with Simulated Rainfall

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Study on Nitrogen and Phosphorus Export from Sloping Croplan...

Early Warning and Emergency Response system for Water Pollution Accidents in Wuhan City, china

The 12th Asian Pacific Confederation of Chemical Engineering Congress

作者： Yang Gao Pei Zhou Bo Zhu Chi-yuan Miao Jia-liang Tang Tao Wang department of environmental,science and Engineering,Shanghai Jiaotong university,Shanghai,20024.,{4. Institute of Motmtain Hazards and environment,the Chinese Academy of sciences,chengdu,61004.,{4. School of Geography,Beijing normal university,Beijing,100785,{4.

Phosphorus and nitrogen released through runoff to surface waters and drinking water sys- tems represent a risk to human and environmental *** study focuses on phosphorus and nitrogen loss from sloping land of purple soil under different slope gradients,coverage and rainfall *** intensity field rainfall simulations were performed on 4.5m long×1.5m wide

关键词： Overland flow subsurface runoff phosphorus nitrogen

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Early Warning and Emergency Response system for Water Pollut...

STUDY ON HARVESTED POPULATION WITH DIFFUSIONAL MIGRATION

2009 International Conference on environmental science and Information Application Technology

作者： Xuying Yuan1 2 Yijin Wu1* Shuang Liang1 Wei Liao1 Liangyue Tian1 Xi Huang1 Hao Zhang1 Bei Huang1 1 Urban and environmental science department of Central china {4. university Wuhan china 4.0079 2 resources and environment science department of Wuhan university Wuhan china 4.0079

Safe and reliable drinking water is vital to every community. But Water pollution incidents have taken place in china frequently resulting in an enormous economic loss. How to solve the problem becomes a significant issue to scrub the deleterious effects of pollution accidents. So the establishment of response models of water pollution accidents in Wuhan city is necessary in order to enhance rapidity, effectiveness and accuracy of emergency commanding, and to improve the level of scientific decision-making. As Emergency pollution management system is a complete system composed of data layer, model layer, the system interface layer and network layer. It also has early warning functions such as the real-time monitoring of water quality and water quality prediction of water pollution accidents. Early Warning and Emergency Response system for Water Pollution Accidents in Wuhan City, china shows a quick-acting and accurate numerical method to calculate the value of pollutant concentration in a short time.

关键词： Early Warning Emergency Response system Water Pollution Wuhan City

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Journal of Systems science & Complexity 2001年第2期14卷 139-148页

作者： FAN Meng WANG Ke (Deportment of Mathematics, Northeast normal university, Changchun 130024. china) ZHANG Yujuan ZHANG Shuwen LIU Huimin (department of Mathematics, Anshan Teacher’s College, Anshan 114.05, china) 东北师范大学吉林长春 130024 鞍山师范学院辽宁鞍山 114005

This paper is devoted to the study of the dynamical behavior and harvesting problem of an exploited population with diffusional migration, for which a protective patch is established. We examine the effects of protective patch and harvest on the population resources and conclude that the protective patch is effective for the conservation of population resources and ecological environment, though in some cases the extinction can not be eliminated. The dangerous region, the parameters domains and the typical bifurcation curves of stability of steady states for the considered system are determined. The optimal harvest policy for the considered population is made also. The explicit expressions are obtained for the optimal harvesting effort, the maximum sustainable yield and the corre- sponding population density. Our results provide a theoretical evidence for the practical management of biological resources.

关键词： Protective patch diffusional migration harvest.

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陕西省生物质能开发利用的前景和对策分析

陕西师范大学学报（自然科学版） 2008年第S1期36卷 126-127页

作者：徒向东西北大学城市资源学系陕西西安710127

大力开发利用生物质能,对于缓解陕西省能源供应和环境压力,实现可持续发展具有重要的意义。对于秸秆利用、发展生物液体燃料、垃圾发电和废弃物综合利用中出现的问题,需相关部门采取有效政策和保障措施加以解决,以利于生物质能开发利用... 详细信息

大力开发利用生物质能,对于缓解陕西省能源供应和环境压力,实现可持续发展具有重要的意义。对于秸秆利用、发展生物液体燃料、垃圾发电和废弃物综合利用中出现的问题,需相关部门采取有效政策和保障措施加以解决,以利于生物质能开发利用健康、有序的发展。

关键词：生物质能秸秆气化垃圾发电

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四川省阿坝州生物资源开发利用研究

四川师范大学学报（自然科学版） 1995年第3期18卷 57-64页

作者：张本能杨人立四川师范大学生物系四川省原子核应用技术研究所

本文报导阿坝州的自然环境特征，生物资源现状及评价，并提出切合实际的开发利用意见。

关键词：开发利用四川生物资源阿坝州

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川东石炭系碳酸盐岩沉积环境探讨

天然气工业 1999年第4期19卷 19-22页

作者：钱峥石油大学资源科学系

依据岩石学、古生物及地球化学沉积相标志的研究，川东石炭系沉积环境的演变经历了蒸发膏湖—咸化泻湖—陆表海三个主要阶段。川东地区早石炭世末期，受中国南方发生较大规模海退的影响，黄龙组沉积早期（Ｃ２ｈｌ１）受古高地的阻隔，... 详细信息

依据岩石学、古生物及地球化学沉积相标志的研究，川东石炭系沉积环境的演变经历了蒸发膏湖—咸化泻湖—陆表海三个主要阶段。川东地区早石炭世末期，受中国南方发生较大规模海退的影响，黄龙组沉积早期（Ｃ２ｈｌ１）受古高地的阻隔，发育膏湖沉积：由于干旱炎热的气候，水体蒸发量大于注入量，水体循环较差，沉积了大面积的白云岩和石膏沉积。黄龙组沉积中期（Ｃ２ｈｌ２）以咸化泻湖沉积为特点，以白云岩沉积为主，表现为多个自下而上由粒屑云岩—粉微晶云岩—干裂角砾云岩组成的向上变浅序列的叠合，具明显的旋回性，反映了高能浅滩与间歇性暴露地表交替出现的结果。黄龙组晚期（Ｃ２ｈｌ３）海平面上升，江南古陆没入海平面之下，扬子准地台形成陆表海环境，属开阔台地环境的浅水沉积，石灰岩类普遍发育，以有孔虫、红藻、珊瑚、腕足、苔藓等为主组成的生屑灰岩大量出现，表明沉积水体较为通畅。

关键词：石炭系碳酸盐岩沉积环境川东地区

Comparative Analysis of Photosynthesis of Three Stipa Species Based on A Photosynthesis Model

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Comparative Analysis of Photosynthesis of Three Stipa Specie...

2011 Chinese Control and Decision Conference（CCDC）

作者： Chan Zhou is with College of Life science,Liaoning university,Shenyang,110036,china Zhuo Zhang is with College of Biology and environment Engineering,Shenyang university,Shenyang,11004.,china .Yunfei Yang is with Institute of Grassland science,Northeast normal university,Key Laboratory for Vegetation Ecology,Ministry of Education,P.R.china,Changchun,130024.china.Qiong Gao is with College of resources science and Technology,Beijing normal university,Key laboratory of environmental Change and Natural Disasters,Ministry of Education,Beijing,100875,china.

We compared photosynthetic characteristics of three Stipa species in NECT,Stipa baicalensis,*** and *** based on ecophysiological traits derived from parameters of a photosynthesis *** net photosynthesis rates,transpiration rate and stomatal conductance,together with microclimate variables of the respective species and sites were observed in July *** photosynthesis rates of three Stipa species were then regressed on incident light intensity,leaf temperature and CO2 partial pressure,and stomatal conductance by means of the nonlinear least square technique and the modified Thornley and Johson’s leaf photosynthesis *** results showed that Thornley and Johson’s photosynthesis model explained on 60.4.%,86.17% and 81.36% of variations in observed net photosynthesis rates for three ***,*** and ***,*** difference in photosynthetic characteristics for three Stipa species explained adaptation to conditions of their respective *** photo efficiency of *** is an adaption to lower photosynthetic active radiation （PAR） at high latitude of the meadow steppe *** the other hand,*** in typical steppe and *** in desert steppe sites are located at lower latitude with more available PAR,thus they showed relative lower photon *** conductance of *** is low because of their low leaf nitrogen concentration,which may be caused by the low available soil nitrogen due to low decomposition rates at high *** contrast to ***,*** shows much lower base rate of mitochondria respiration because of higher leaf temperature often experienced by plants at desert steppes.

关键词： Stipa species photosynthesis characteristics photosynthesis model

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双网卡冗余在嵌入式容错网络中的设计与实现

四川师范大学学报（自然科学版） 2003年第6期26卷 661-663页

作者：罗雪松蒋涛罗蕾许子辛电子科技大学计算机学院四川成都610054 四川师范大学物理系四川成都610066

为了尽量避免嵌入式网络中网络节点故障和链路故障所带来的损失,在容错网络中,需要经过良好设计的故障恢复方案,以便于在网络通信中获取较高的可靠性和易用性.提出并详细介绍了一种基于双网卡的网络冗余方法.该方法包含了故障检测和故... 详细信息

为了尽量避免嵌入式网络中网络节点故障和链路故障所带来的损失,在容错网络中,需要经过良好设计的故障恢复方案,以便于在网络通信中获取较高的可靠性和易用性.提出并详细介绍了一种基于双网卡的网络冗余方法.该方法包含了故障检测和故障恢复方法.故障检测方法使用链路状态检测与Loop back检测相结合的方式;故障恢复方法在发现激活物理层故障后,将引导系统使用备用物理层.这种网络冗余方式的实现有效地提高了嵌入式网络设备的通信可靠性.又由于实现方便,造价低,可靠性高的特点,使其在现实的容错网络中获得了广泛的应用.

关键词：冗余故障恢复故障检测