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61.
Independent teams undertook environmental monitoring of particular concentrations of major construction projects forming part of Hong Kong’s U.S. $20 billion airport infrastructure programme located in dense urban areas. The team combination of environmental specialists with experienced civil engineers enabled pragmatic mitigation measures to be developed and accepted by the construction personnel with the result that potentially significant adverse impacts were averted. The authors discuss the mechanism and success of this innovative approach. 相似文献
62.
流行病学调查结果表明,环境的极低频电磁场暴露与人群某些肿瘤,如白血病、乳腺癌、脑肿瘤等,以及生殖、神经、心血管和内分泌等系统疾患的发病相关,这些结果在一定程度上得到实验室人体测试的支持。然而,极低频电磁场对健康影响的确切效应,迄今尚未能作出结论,亟等进一步开展多层次、多水平的研究。 相似文献
63.
William D. Boelter MD Beth Ann Burt Elaine B. Spector David R. Hinton Zdena Pavlova Atsuko Fujimoto 《黑龙江环境通报》1990,10(11):703-715
A pregnant woman with indeterminate Duchenne muscular dystrophy (DMD) carrier status, but with DMD diagnosed in her deceased brother (unavailable for study), presented for prenatal diagnosis, intending to continue the pregnancy only if proven unaffected with DMD with near absolute certainty. Creatine kinase (CK) assays to clarify carrier status were inconclusive. Male sex in the fetus was identified, but DNA restriction fragment length polymorphism (RFLP) analysis was not yet available to this centre to investigate the possible transmission of the DMD gene, and the pregnancy was terminated. Tissue histology and dystrophin protein analysis demonstrated the absence of DMD. In a situation with proven maternal carrier status, future fetal inheritance of the opposite maternal X chromosome would indicate the presence of DMD. However, maternal carrier status remained in doubt through a second pregnancy, even with RFLP studies, and was finally established when dystrophin analysis confirmed the presence of DMD in the second fetus. Histologic findings are presented, contrasting features in the two fetuses. The value of dystrophin analysis for establishing the diagnosis of fetal DMD, in this case proving maternal carrier status in a difficult situation, and for demonstrating DMD gene:RFLP haplotype relationships is illustrated. 相似文献
64.
Andreas Züttel 《Mitigation and Adaptation Strategies for Global Change》2007,12(3):343-365
Hydrogen storage and transportation or distribution is closely linked together. Hydrogen can be distributed continuously in
pipelines or batch wise by ships, trucks, railway or airplanes. All batch transportation requires a storage system but also
pipelines can be used as pressure storage system. Hydrogen exhibits the highest heating value per weight of all chemical fuels.
Furthermore, hydrogen is regenerative and environment friendly. There are two reasons why hydrogen is not the major fuel of
toady’s energy consumption: First of all, hydrogen is just an energy carrier. And, although it is the most abundant element
in the universe, it has to be produced, since on earth it only occurs in the form of water. This implies that we have to pay
for this energy, which results in a difficult economic task, because since the industrialization we are used to consuming
energy for free. The second difficulty with hydrogen as an energy carrier is the low critical temperature of 33 K, i.e. hydrogen
is a gas at room temperature. For mobile and in many cases also for stationary applications the volumetric and gravimetric
density of hydrogen in a storage system is crucial. Hydrogen can be stored by six different methods and phenomena: high pressure
gas cylinders (up to 800 bar), liquid hydrogen in cryogenic tanks (at 21 K), adsorbed hydrogen on materials with a large specific
surface area (at T < 100 K), absorbed on interstitial sites in a host metal (at ambient pressure and temperature), chemically bond in covalent
and ionic compounds (at ambient pressure), oxidation of reactive metals e.g. Li, Na, Mg, Al, Zn with water. These metals easily
react with water to the corresponding hydroxide and liberate the hydrogen from the water. Finally, the metal hydroxides can
be thermally reduced to the metals in a solar furnace. 相似文献
65.
William G. Coleman 《Environmental management》1996,20(6):815-825
The term biodiversity describes the array of interacting, genetically distinct populations and species in a region, the communities they comprise, and the variety of ecosystems of which they are functioning parts. Ecosystem health, a closely related concept, is described in terms of a process identifying biological indicators, end points, and values. The decline of populations or species, an accelerating trend worldwide, can lead to simplification of ecosystem processes, thus threatening the stability and sustainability of ecosystem services directly relevant to human welfare in the chain of economic and ecological relationships. The challenge of addressing issues of such enormous scope and complexity has highlighted the limitations of ecology-as-science. Additionally, biosphere-scale conflicts seem to lie beyond the scope of conventional economics, leading to differences of opinion about the commodity value of biodiversity and of the services that intact ecosystems provide. In the face of these uncertainties, many scientists and economists have adopted principles that clearly assign burdens of proof to those who would promote the loss of biodiversity and that also establish near-trump (preeminent) status for ecological integrity. Electric utility facilities and operations impact biodiversity whenever construction, operation, or maintenance of generation, delivery, and support facilities alters landscapes and habitats and thereby impacts species. Although industry is accustomed to dealing with broad environmental concerns (such as global warming or acid rain), the biodiversity issue invokes hemisphere-wide, regional, local, and site-specific concerns all at the same time. Industry can proactively address these issues of scope and scale in two main ways: first, by aligning strategically with the broad research agenda put forth by informed scientists and institutions; and second, by supporting focused management processes whose results will contribute incrementally to the broader agenda of rebuilding or maintaining biodiversity. 相似文献
66.
William Wanjala Toili 《The Environmentalist》1996,16(3):221-229
Summary Whether environmental education in the school curriculum is treated as a separate subject or as an interdisciplinary entity, the end product should be the same: to provide learners with the desire to preserve or develop optimum environments and to improve less desirable ones. In this endeavour, the learners must ultimately reach out to participate in community decisions and environmental management activities, for that is where the environmental problems abound. Moreover, young persons are generally more knowledgeable than many adults on environmental matters and are more aware of the effects of environmental degradation. When they participate in community environmental management, they may also develop unique and particularly dynamic qualities.Research worldwide suggests that very few teaching programmes encourage environmental participation. In Kenya teachers tend to use deductive teaching methods which do not encourage participation, although there may be ample opportunities in the local environment to facilitate such participation. A more refined, reconstructivist inquiry strategy, committed to the attainment of participative environmental education objectives is suggested. The approach, referred to as an operation-environment instructional model emphasizes action research, supported by a series of other vital stages, as fundamental to the agenda for environmental learning.William W. Toili possesses both Bachelor and Master's Degrees in Education from Nairobi as well as a Master's Degree from the University of Leeds, UK. He is currently a lecturer in Environmental Education at Maseno University College. 相似文献
67.
68.
William Lin Robert L Spore Edmund A Nephew 《Journal of Environmental Economics and Management》1976,3(3):236-252
This study quantifies the short-run impacts of reclamation on strip mining costs, coal prices, production, and employment in Appalachia. A process analysis model is developed and used to estimate short-run strip-mined coal supply functions under conditions of alternative reclamation requirements. Then, an econometric model is developed and used to estimate coal demand relations. Our results show that full reclamation has rather minor impacts. In 1972, full reclamation would have increased strip-mined coal production costs an average of $0.35 per ton, reduced strip-mined coal production by 10 million tons, and cost approximately 1600 jobs in Appalachia. 相似文献
69.
70.
FUENSANTA CARAVACA DINO FIGUEROA ANTONIO ROLDÁn CONCEPCIÓN AZCÓN-AGUILAR 《Environmental management》2003,31(3):0412-0420
The reestablisment of autochthonous plant species is an essential strategy for recovering degraded areas under semiarid conditions.
A field experiment was carried out to assess the short-term effect of two reafforestation methods involving mycorrhizal inoculation
and compost addition on soil quality parameters and Rhamnus lycioides seedling growth. The nutrient content (NPK) and enzymatic activities (dehydrogenase, urease, protease-BAA, acid phosphatase
and β-glucosidase) increased and bulk density decreased in the rhizosphere soil with the organic amendment. Biomass C of rhizosphere
soil increased by at least 240% with respect to the control soil after mycorrhizal inoculation and the combination of compost
addition + mycorrhizal inoculation. Both mycorrhizal inoculation and composted organic residue addition increased R. lycioides seedling growth in the same proportion. In the short term, we conclude that the application of both reafforestation methods
not only enhances the establishment of R. lycioides seedlings, but also improves soil quality. 相似文献