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281.
Fang Qinhua Zhang Luoping Hong Huasheng Chen Weiqi Jiang Yuwu Chen Bin 《中国人口.资源与环境(英文版)》2006,4(3):45-50
Recently, there has been growing concerns about environmental issues related to urbanization in China. The intense natural resources utilization and increasing population has brought great pressure, especially in coastal areas, consequently affecting the sustainable development of coastal cities. In 2002, Environmental Impact Assessment Act (EIA Act) was enacted in China. Environmental impact assessment targeted at planning, one level of strategic environmental assessment (SEA), thus became a legislative requirement. This paper considers SEA to be one of the important approaches not only to control coastal pollution, but also to conserve coastal ecosystems and finally to achieve sustainable development during urbanization, thus it will be a set an example for other areas of China. The experience of SEA in Xiamen, a coastal city in southeast China, illustrates the potentials of SEA. This paper first briefly introduces the concept and potentials of SEA, then compares two SEA cases and a project EIA case in Xiamen, and finally identifies the key characteristics of SEA. 相似文献
282.
国外防护服技术的发展 总被引:1,自引:0,他引:1
高方 《中国安全科学学报》1993,3(4):18-21
近十几年来,国际上防护服技术发展非常迅速,主要表现在:国际性学术会议举行频繁;学术性团体相继成立;学术论文数量增加很快;新品种不断出现;市场形势看好。发展迅速的主要原因是:皮肤防护意识的加强;法规和标准化建设的推动;新型防护材料的发展;基础研究工作的深入。但就整体而言,防护服技术仍是一个比较年轻的处于初始阶段的学科,许多问题有待解决。预计近期内仍将是一种蓬勃发展的形势。 相似文献
283.
本文采用万元产值取水量和水重复利用率作为节水指标,通过对山东省主要工业行业用水节水现状进行调查研究,阐述了各行业节水水平和节水经验,分析并预测了节水潜力,总结提出了各行业应采取的主要节水措施和建议。 相似文献
284.
Pei-Yi Lin Yi-Ya Fang Su-Ping Wang Mei-Yun Tai Yuan-Feen Tsai 《Die Naturwissenschaften》2012,99(3):185-189
After extinction, the reappearance of a conditioned response induced by an unconditioned stimulus which is weaker than that
used during the conditioning training indicates that the extinction procedure does not eliminate the original conditioned
memory. Recent studies on fear conditioning have shown that rats exhibited little or no recovery of conditioned responding
if the time interval between fear acquisition and extinction was short, suggesting that the extinction process may erase the
original conditioning trace in this situation. In the present study, a saving experiment was conducted in rats to investigate
whether an aversive response could be recovered following extinction training with different time intervals after acquisition
of conditioned taste aversion (CTA). Male Long–Evans rats developed CTA by associating a 0.2% sucrose solution with malaise
induced by intraperitoneal injection of 4 ml/kg 0.15 M LiCl and were subjected to extinction training with an interval of
5 h (5H group) or 24 h (24H group) after acquisition of CTA. Rats in the 5H group, but not in the 24H group, exhibited no
aversive responding to the sucrose solution followed by the injection of a lower dose of LiCl (1 ml/kg). These findings indicate
that the extinction procedure administered at different time points following the acquisition of CTA affects recovery of extinguished
aversive memory and suggest that an unlearning process may be involved in the mechanisms of CTA extinction with short intervals
between acquisition and extinction. 相似文献
285.
通过在双金属氢氧化物MgAl-LDHs表面定向固定纳米尺度的CoZn-ZIF,并原位生长形成CoZn-ZIF/MgAl-LDHs复合材料.利用扫描电子显微镜(SEM),傅里叶变换红外光谱仪(FT-IR),X射线衍射(XRD)和热重差热综合热分析仪(TGA/DSC)分析手段对材料进行表征,考察CoZn-ZIF/MgAl-LDHs复合材料对正己烷中碘分子的吸附行为,讨论了吸附时间和吸附温度对吸附性能的影响.此外,还对吸附过程的吸附动力学和热力学进行详细的研究,考察准一级和准二级动力学模型,Langmuir和Freundlich等温吸附模型探究该材料的吸附机理.实验结果表明,CoZn-ZIF/MgAl-LDHs对碘的吸附行为符合准二级动力学模型,吸附平衡时间为225 min.通过Langmuir等温方程得到最大平衡吸附量为344.3322 mg·g~(-1),碘的吸附过程更好地拟合Freundlich等温方程,说明反应是多分子层吸附过程,同时,由热力学数据得知该吸附是以物理吸附为主的放热过程,降低温度对吸附过程更有利. 相似文献
286.
采用数值模拟的方法,研究了街谷内上风建筑与上游阻挡建筑的间距(D),即上游建筑间距,对街谷内空气流动特性和气态污染物分布规律的影响.模拟结果表明,街谷内迎风区的气流速度基本不随D的变化而变化,而背风区和中心区的气流速度随着D的增加呈现先减小后增大的趋势,并在D=90m时,气流速度达到最小值.相应地,在D=90m时街谷内污染物浓度最高,表明D存在最不利值,在城市规划中应尽可能避免该间距.当D大于90m时,D越大,污染物浓度越低,而D小于90m时,D越小,污染物浓度也越低,可以同时实现节约用地和减小交通污染的目的. 相似文献
287.
基于水质评价的综合污染指数(CWQI)法和水质指标实测含量的统计分析,应用Monte Carlo模拟方法,建立了河流水质评价的Monte Carlo-CWQI耦合模型并进行实例研究.通过建立的耦合模型和温瑞塘河流域14个监测断面2004~2010年的水质监测数据,定量分析各监测断面隶属于不同污染等级的概率水平和各水质指标对水体污染的影响程度.结果表明:温瑞塘河水系水质污染十分严重,勤奋、九山、东水厂、十字河、南白象、灰桥、新桥、米筛桥、仙门、光明、郭溪、瞿溪、西岙和梧田监测断面处于重度污染的概率分别为28.50%,0.55%,92.71%,59.73%,78.85%,39.38%,78.87%,83.09%,65.32%,78.08%,0.00%,0.96%,68.09%,86.06%;处于严重污染的概率分别为71.28%,0.01%,4.33%,39.76%,21.07%,60.59%,4.42%,12.41%,11.02%,21.24%,0.00%,0.02%,1.42%,13.12%.各监测断面总氮(TN),氨氮(NH3-N)和溶解氧(DO)的Spearman等级相关系数范围分别是0.41~0.76、0.25~0.63和0.14~0.66,是其他指标的2倍以上,表明影响该地区水质达标的主要因子是TN,NH3-N和DO.本研究拓宽了河流水质评价的研究视角,能够为流域水环境管理提供丰富的决策依据. 相似文献
288.
Qing Wu Li He Zhong Wei Jiang Yang Li Ting Ting Zhao Yu Han Li Cheng Zhi Huang Yuan Fang Li 《环境科学学报(英文版)》2019,31(12):203-212
Efficient removal of non-biodegradable and hazardous dyes from wastewater remains a hot research topic. Herein, a rationally designed a Cu(Ⅱ)-based metal–organic gel(Cu-MOG) with a nanoporous 3 D network structure prepared via a simple one-step mixing method was successfully employed for the removal of cationic dyes. The Cu-MOG exhibited high efficiency, with an adsorption capacity of up to 650.32 mg/g, and rapid adsorption efficiency, with the ability to adsorb 80% of Neutral Red within 1 min. The high adsorption efficiency was attributed to its large specific surface area, which enabled it to massively bind cationic dyes through electrostatic interaction, and a nanoporous structure that promoted intra-pore diffusion. Remarkably, the Cu-MOG displayed size-selective adsorption, based on adsorption studies concerning dyes of different sizes as calculated by density functional theory. Additionally, the adsorption performance of the Cu-MOG still maintained removal efficiency of 100% after three regeneration cycles. These results suggested that the Cu-MOG could be expected to be a promising and competitive candidate to conveniently process wastewater. 相似文献
289.
290.
Zhuang Yahui Zhang Hongxun Wang Xiaoke & Fang JinyunResearch Center for Eco-Environmental Sciences 《中国人口.资源与环境(英文版)》2004,2(2)
This report summarizes the surveys on carbon inventories and initiatives on sustainable carbon cycling taken by RCEES. The first part of this report deals with the concept of sustainable carbon cycling, the historical evolution of carbon cycling processes in China, carbon pool enhancement, value addition, carbon sequestration and carbon balance. The second part covers the modeling of carbon dynamics, emission inventories of various carbon containing greenhouse gases and their potential abatement measures. 相似文献