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91.
Victor E. Gleason 《Journal of the American Water Resources Association》1978,14(3):532-541
ABSTRACT: California's courts have recently recognized the existence of underground aquifer storage rights that permit public agencies to (1) store imported waters in aquifers; (2) prevent others from expropriating that water; and (3) recapture the stored water when it is needed. The article describes the two appellate decisions that represent the common-law development of aquifer storage rights. Each decision related to separate aquifers that were subject to separate types of groundwater management programs. One decision involved an aquifer under the southeastern San Francisco Bay area that was managed under statutory authority and is entitled, Niles Sand and Gravel Co. v. Alameda County Water District 37 C.A.3d 924 (1974); cert. denied 419 US 869. The other decision involved an aquifer under Southern California's San Fernando Valley that was managed under judicial authority and is entitled, City of Los Angeles v. City of San Fernando 14 Cal.3d 199 (1975). The two decisions provide separate, but complimentary, public interest rationales for aquifer storage rights: (1) to protect water supplies necessary for the overlying community; and (2) to increase water supply efficiencies by using natural underground reservoirs wherever practicable. The Article reviews the relationship of aquifer storage rights to conventional groundwater rights and indicates aspects of the storage right that may need additional development. 相似文献
92.
塔里木沙漠油田开发工程的环境影响评价 总被引:1,自引:0,他引:1
塔里木是一个内陆封闭盆地,是世界第二大流动沙漠,它具有丰富的油气资源,目前正在积极开发中。在油气田开发过程中必须做环境影响评价,文中介绍了沙漠环境及生态状况,在沙漠区域必须以水域和生态环境影响评价为重点,评价结果应提出固沙、防沙和保护自然生态等一系列防治措施和对策。 相似文献
93.
彭国生 《中国安全科学学报》2003,13(5):20-23
从油田企业生产的工艺特点、历史条件、社会背景以及跨国经营合作等方面出发 ,分析了油田企业安全生产特殊性。同时指出了目前油田企业安全管理存在着四方面的主要问题 ,并针对存在的主要问题 ,提出了更新管理观念、强化安全生产责任制、加大科技投入、完善HSE体系标准、加强隐患治理、加大培训力度等 6项安全管理对策 ,对油田企业安全生产具有一定的指导意义。 相似文献
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97.
通过对典型发电与高压输变电工程工频电磁场的现场检测,阐明了发电与高压输变电工程的工频电磁场现状.在此基础上,根据科学界关于极低频电磁场对人体短期和长期效应研究的明确结论,介绍了发电与高压输变电工程的工频电磁场暴露对人体健康的影响.同时,从卫生安全的角度提出了防止和减少工频电磁场影响的综合防护措施,其中包括:慎重选址,合理设计,适当个体防护和必要的警示标识.另外,扼要地介绍了工频电磁场的有关卫生标准和测量方法. 相似文献
98.
E. Battisti A. Albanese L. Bianciardi A. I. Fiaschi M. Rigato A. Vittoria G. L. Messa N. Giordano 《The Environmentalist》2009,29(2):190-195
The utility and the safety of the extremely low frequencies (ELF) electromagnetic fields in the treatment of numerous diseases
have been demonstrated. Moreover, the effects of these fields seem to depend on their respective codes (frequency, intensity,
waveform). We want to value the effects and the safety of the therapeutic application of a musically modulated electromagnetic
field (TAMMEF) system, which field is piloted by a musical signal and its parameters (frequency, intensity, waveform) are
modified in time, randomly varying within the respective ranges, so that all possible codes can occur during a single application.
Sixty subjects, affected by shoulder periarthritis were enrolled in the study and randomly divided into three groups of 20
patients each: the first exposed to TAMMEF, the second exposed to ELF, the third exposed to a simulated field. All subjects
underwent a cycle of 15 daily sessions of 30 min each and a clinical examination upon enrolment, after 7 days of therapy,
at the end of the cycle and at a follow-up 30 days later. All the patients of TAMMEF group and ELF group completed the therapy
without the appearance of side effects: they presented a significant improvement of the subjective pain and the functional
limitation, which remained stable at the follow-up examination. In those exposed to a simulated field group, there was no
improvement of the pain symptoms or articular functionality. This study suggests that the TAMMEF system is efficacious and
safe in the control of pain symptoms and in the reduction of functional limitation in patients with shoulder periarthritis.
Moreover, the effects of the TAMMEF system cover those produced by the ELF field. 相似文献
99.
Occupational exposure to radiofrequency (RF) and static magnetic fields at magnetic resonance imaging (MRI) suites is of continuing
concern to personnel who routinely work in this environment. Questions regarding the levels of occupational RF and static
field exposure have increased with the increasing demand for anesthetics to be administered in this environment. The present
study was thus designed towards addressing the above-mentioned problem by gaining information regarding exposure levels of
clinical personnel at MRI units in South Africa. Three 1.5 MRI units in Bloemfontein, South Africa were utilized to evaluate
the exposure of clinical personnel to the electromagnetic fields present in the MRI environment over a period of time and
during different clinical MRI procedures. Three rounds of measurements of RF fields in the MRI environment were done. All
the three measurement rounds were focused on the low frequencies, 5 Hz–32 kHz, as well as on the high frequencies, 300 kHz–40 GHz.
First round measurements were done to establish the background of the RF fields in and around the magnet room during an MRI
examination. Second round RF field measurements were done at a specific location, 1 m away from the bore on the right-hand
side of the bed, in the MRI room. The third round measurements were of the same format as the second round, but the specific
location was against the magnet bore. Two pieces of Narda Safety Test Solution instruments, the EFA-300 and EMR-300, were
used to measure the electromagnetic and magnetic exposure fields generated from the MRI scanners. Results of the measurements
indicate that the electromagnetic fields measured during different clinical procedures do not exceed the International Commission
on Non-Ionizing Radiation Protection (2000) guidelines in these units. Results from round two and three showed that the RF
and gradient exposure 1 m and up against the bore entrance does not exceed these guidelines (rms average over 6 min). Ongoing
new developments in MRI scanning create the need for continuously monitoring exposure of patients and workers to the EMF fields
in the MRI environment. 相似文献
100.
国内外生态足迹研究进展 总被引:9,自引:0,他引:9
在可持续发展的定量研究中,生态足迹形象地反映了人类经济活动对环境影响的程度,对地区可持续发展的决策具有一定的指导意义。本文阐述了:(1)生态足迹的理论背景、相关概念、计算方法以及与能值分析法、产品生命周期法和投入产出法等综合应用的趋势;(2)生态足迹在全球、国家、地区尺度上的研究成果,以及在国际贸易、能源、旅游、交通、饮食等领域的应用进展;(3)土地互斥假设、全球面积单位、等效因子取值以及研究尺度方面的局限性。最后,本文指出了在多指标整合、污染影响分析和家庭消费尺度研究等方面的研究趋势。 相似文献