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261.
本文应用主分量分析法,对吴忠新灌区生态经济类型进行了初步划分与研究。分析结果表明,该区可划分为五个明显不同的生态经济类型区,各区的生态条件、经济、环境均存在较大差异,故此,在制定其发展方向及开发措施时,应区别对待。 相似文献
262.
Managing Watershed Externalities in India: Theory and Practice 总被引:2,自引:0,他引:2
John Kerr Grant Milne Vasudha Chhotray Pari Baumann A.J. James 《Environment, Development and Sustainability》2007,9(3):263-281
Watershed development is the focus of poverty alleviation programs in rural India. Watershed projects aim to solve problems
of externalities, but they also create their own externalities, which cause uneven distribution of costs and benefits that
undermine project objectives and harm the poor. Numerous approaches exist to internalize externalities, including awareness
creation, moral suasion, investment subsidies, regulatory limits and fines, indirect benefits, mergers, and recent innovations
like payment for environmental services and cap and trade. These can be judged on several criteria; the best approach would
solve the problem cost effectively and help or at least not hurt poor people. Watershed projects in India were examined to
identify the approaches taken to internalize watershed externalities. Investment subsidies and indirect employment benefits
are the least effective approaches theoretically, but they are the most commonly applied, most likely because they are easy
to administer and bring popular short term gains. Some theoretically favorable approaches that have been used elsewhere, such
as payment for environmental services, may not work as well in India due to high transaction costs. However, one key innovation
that easily could be applied in India is to make investment subsidies contingent on performance. Legal support and property
rights reform would be needed for other favorable approaches. 相似文献
263.
《中国安全科学学报》1992,(4)
提出交通系统主体工种中存在的主要职业危害;简析消除或减轻职业危害的主要途径;论述交通系统卫生工程技术发展趋势。 相似文献
264.
Owen P. Phillips MD Lee P. Shulman Lisa A. Altieri R. Sidney Wilroy Donald S. Emerson John V. Dacus Sherman Elias 《黑龙江环境通报》1991,11(9):705-710
A 21 -year-old woman with progressively deforming or type III osteogenesis imperfecta (OI) presented for prenatal counselling and diagnosis at 10 weeks' gestation. Family history was non-contributory. At 14.8 weeks' gestation, ultrasonographic examination revealed fetal skeletal hypomineralization, easily compressible fetal cranium, and thickened long bones, indicating that the fetus was also affected. Confirmation of the prenatal diagnosis of OI type III was made following a Caesarean section birth of a male infant with multiple skeletal deformities and blue sclerae implying, in this case, autosomal dominant inheritance. 相似文献
265.
266.
针对钻井废水含油量高、化学需氧量高、悬浮物浓度及色度高的特点,综述了化学破乳法在钻井废水处理中的应用,详细阐述了化学法破乳的机理、絮凝剂的种类和性能。并提出絮凝剂逐渐由无机向有机和天然高分子化合物,由单一型向复合型转化的发展方向。 相似文献
267.
高职高专院校公共选修课程体系探究 总被引:2,自引:0,他引:2
针对一些高职高专院校重技能、轻人文而导致公共选修课建设甚至缺失的现象,对公共选修课程体系建构在目标、内容方面作了详细阐述,并对课程类型的设置、开设年级和课时比例设置提出了建议。 相似文献
268.
巨灾债券与政府灾害救助 总被引:1,自引:0,他引:1
发生概率小而损失巨大的巨灾无疑对国民经济有着重要的影响。我国幅员辽阔,尽管每年灾害的性质和发生地点不同,但是损失总量和政府救灾的支付总量却是一个稳定的大数,然而依然不能满足救灾与恢复生产的需要。借鉴经济发达国家保险业的巨灾债券,首次提出在政府救灾中引入市场机制——发行政府巨灾债券。这对于投资者是收益高的风险投资,对于政府可以减轻公共财政负担,而对于受灾地区则可以获得更多的资金支援,加快恢复生产,保证经济增长的稳定性。 相似文献
269.
270.
J. L. M. Keulemans I. Sinigerska V. H. Garritsen J. G. M. Huijmans Y. V. Voznyi O. P. van Diggelen W. J. Kleijer 《黑龙江环境通报》2002,22(11):1016-1021
Prenatal diagnosis of the Hunter syndrome (mucopolysaccharidosis type II; MPS II) is preferably achieved by the assay of iduronate-2-sulphate sulphatase (IDS) in uncultured chorionic villi (CV) as this allows early (12th week), rapid (2–3 days) and reliable results. We summarize the results of 174 prenatal analyses in the past 30 years, using various methods such as radiolabelled sulphate incorporation in amniotic fluid (AF) cells, glycosaminoglycan (GAG)-electrophoresis in AF and IDS assay in CV, CV-cells, AF and AF-cells. Twenty-seven fetuses with MPS II were diagnosed after finding clearly abnormal results in pregnancies with a male fetus; very low IDS activity has also been measured in some pregnancies with a (heterozygous) female fetus, emphasizing the need to combine enzyme assay with fetal sex determination. IDS activity has until recently been assessed by a cumbersome radioactive enzyme assay. Here we describe the use of a novel fluorigenic 4-methylumbelliferyl substrate, which allows a sensitive, rapid and convenient assay of IDS activity and reliable early prenatal diagnosis. This novel IDS assay was validated in retrospective analyses of 14 CV, CV-cell, AF and AF-cell samples from affected pregnancies in addition to prospective prenatal diagnosis in eight pregnancies at risk with one MPS II-affected fetus. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献