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981.
提出用微波加热一二氧化碳活化法再生乙酸乙烯合成用触媒载体废活性炭工艺。采用条件实验法研究了活化时间、二氧化碳流量和微波功率对活性炭碘吸附值,亚甲基蓝吸附值和再生得率的影响,得到微波辐射加热二氧化碳活化再生乙酸乙烯用触媒载体废活性炭的最佳工艺条件为活化时间25min,二氧化碳流量0.2L/min,微波功率700w。在此条件下制得的活性炭碘吸附值为1158.02mg/g、亚甲基蓝吸附值为240mv,/g、得率为74.19%。并对活性炭进行了比表面积的测定和孔结构的分析,活性炭的比表面积为1308.13m^2/g,总孔容为0.76mL/g。 相似文献
982.
流域水权初始分配机制中的节水激励 总被引:2,自引:0,他引:2
目前,永资源短缺的问题普遍存在,如何利用非工程手段解决水资源的供需矛盾开始成为研究的焦点。水权翩度能够对人们的用水行为产生积极的或消极的影响,而水权初始分配机制是水权制度运行的基础,该机制是否能够激励用水者不断地开发应用节水技术以及在更广泛的领域内减少浪费行为,对于有效地控制用水需求,缓解水资源危机具有十分重要的意义。本文通过构建流域水权初始分配机制节水激励模型,考察在以指标法为基础的水权初始分配过程中,流域各地区可以控制并且能够影响水权分配结果的因素,分析其可能进行的行为选择以及对水资源节约的影响。研究结果表明,决策者可以通过平衡选择现状用水量权重.延长水权初始分配份额的有效期,以及对节水工程投资和水利工程投资进行补贴等手段,使水权初始分配机制在长期内发挥节水激励作用.不仅能够提高各地区的经济收益,并且能够缓解水资源的供需矛盾。实现流域的可持续发展。 相似文献
983.
984.
985.
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
986.
清江流域自然旅游资源调查与评价方法 总被引:5,自引:2,他引:3
根据清江流域自然旅游资源的特色,首先提出了一套对其进行详细系统的调查方法:(1)利用遥感数字图象处理技术及航、卫片解译结果,圈出潜在景区及潜在景点;(2)详细调查、收集及整理清江流域各市、镇已有资料,填写旅游资源调查登记卡片;(3)在(1),(2)基础上,对主要潜在景区及景点进行野外现场调研。然后,以调查结果为前提,提出了采用综合评分法,模糊数学评价方法,信息量评价方法,神经网络评价方法及地理信息 相似文献
987.
湖北野生食果资源特点及其开发途径 总被引:2,自引:0,他引:2
野生食果为营养丰富的食用资源植物。在深入调查的基础上,分析了湖北野生食果资源的特点,提出了野生食果资源开发的对策以及产品深加工的途径,为野生食果资源的开发利用打下了坚实的基础。 相似文献
988.
The establishment of the forest eco-compensation mechanism could realize the value of the forest ecosystem services partly or thoroughly, stress the equality of the stakeholders, encourage public participation in forest ecosystem tendering, and strengthen the capacity of sustainable management. Taking the Hainan province as an example, this study focuses on the analysis of major socioeconomic and ecological impacts of forest eco-compensation in the Qiongzhong County and Lingshui County, and recommends approaches and practices for the establishment of the eco-compensation mechanism in the Hainan Province. Data were collected from a household questionnaire survey. Altogether 120 households have been interviewed, and Statistical Product and Service Solutions (SPSS) was applied for data analysis. Most of the respondents held a positive attitude toward the forest eco-compensation policy which has contributed to the improvement of environmental quality. However, forest protection has limited the opportunities for the income growth of local communities, who have never got sufficient compensation from either the central or local governments. Insufficient financial support to forest institutions and local communities involved in forest management has led to major conflicts in forest management, such as, the conflict between forest protection and local economic development, and decrease in arable land area and increase in surplus labor force. On the basis of case study results, the core issues of forest eco-compensation mechanism in Hainan province are discussed. Finally, suggestions and recommendations that cover forest eco-compensation standards, management institutions, and community capacity building and diversification of financing channels, have been made for the establishment of forest eco-compensation mechanism in Hainan. 相似文献
989.
Jiang Fan Chen Weiping Zhang Tao 《中国人口.资源与环境(英文版)》2007,5(1):33-38
A new bioreactor on the basis of a dynamic fluidized bed was designed, which combines advantages of the fluidized bed and a biological contactor. The experiments of start up, normal operation and parameter adjustment are carried out. The results show that the bioreactor can be quickly started up in the condition that the fill is 50%, the hydraulic retention time is 72 min, aerate speed is 2.5 m3/h, rotation-cage rotated speed is 1.5 r/min, and the removal rates of chemical oxygen demand (CODcr) and Ammonia nitrogen (NH3-N) are 75.34% and 80.98% respectively. The influence of the operation parameter on removal rates of the bioreactor is analyzed, and an appropriate operation parameter is provided. 相似文献
990.
Prenatal diagnosis of monosomy 4p14→pter and trisomy 11q25→qter: clinical presentations and outcomes
Hsiu-Huei Peng Tzu-Hao Wang An-Shine Chao Yao-Lung Chang Shuenn-Dyh Chang Yung-Kuei Soong 《黑龙江环境通报》2005,25(12):1133-1137
We present the case of a pregnant woman with low free β-HCG in maternal serum Down syndrome screening that led to prenatal diagnosis of a fetus with 46,XY,der(4)t(4;11)(p14; q25). This chromosomal aneuploidy resulted from unbalanced segregation of a paternal balanced translocation, t(4;11)(p14;q25). Prenatal ultrasound revealed intrauterine growth restriction, cleft lip and palate, a thick nuchal fold, a single umbilical artery, and pyelectasis. Array-based comparative genomic hybridization and short tandem repeat markers further located the exact breakpoint of translocation. The woman had her pregnancy terminated at 23 weeks of gestational age. The proband had general appearance of Wolf–Hirschhorn syndrome and some unique findings, including single umbilical artery, severe immunoglobulin deficiency, scalp defect, and underlying bony defect. Our case underscores the importance of fetal karyotyping when low maternal serum free β-HCG is found. It also adds information on the fetal presentations of monosomy 4p14→pter and trisomy 11q25→qter. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献