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61.
An omphalocele is a congenital defect in the abdominal wall characterized by absent abdominal muscles, fascia, and skin. The characteristic ultrasound appearance includes a midline defect with herniation of abdominal contents into the base of the umbilical cord. Other anatomic abnormalities are seen in approximately 50% of cases, most notably cardiac defects (19%–32%). Approximately, 50% of cases are associated with genetic and multiple malformation syndromes including trisomy 13/18, pentalogy of Cantrell and Beckwith–Wiedemann syndrome. Therefore, a thorough evaluation is recommended, including detailed anatomic survey, fetal echocardiogram, genetic counseling, and prenatal diagnostic testing. Overall prognosis depends on the size of the omphalocele, genetic studies, and associated anomalies. Early prenatal diagnosis remains important in order to provide parental counseling and assist in pregnancy management. Delivery should occur at a tertiary care center. Timing and mode of delivery should be based on standard obstetric indications with cesarean delivery reserved for large omphalocele (>5 cm) or those that involve the fetal liver. Neonatal management involves either primary or staged reduction, both of which can be associated with a prolonged neonatal hospitalization. 相似文献
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63.
旅游认证体系 总被引:1,自引:0,他引:1
Martha Honey 《生态毒理学报》2002,24(3):28-29
研究者们在全世界范围内确定了约 250种自愿性举措用来设立旅游业标准 . 这些举措包括行动 规范、奖励、标准检测、最佳方法和大约 70种提供批准标识或标志的生态标签和认证体系 . 这些体系越来越多地被用来展示在社会和 /或环境方面较好的行业 . 相似文献
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Diabetes is an increasingly common diagnosis among pregnant women. Pregestational diabetes is associated with an increase in many adverse pregnancy outcomes, which impact both on the woman and her fetus. The models of pregnancy care for women with diabetes are based largely on observational data or consensus opinion. Strategies for aneuploidy screening and monitoring for fetal well-being should be modified in women with diabetes. There is an increasing understanding of the mechanisms by which congenital anomalies and disorders of fetal growth occur, involving epigenetic modifications, changes in gene expression in critical developmental pathways, and oxidative stress. This knowledge may lead to pathways for improved care for these high-risk pregnancies. 相似文献
66.
Dyssegmental dysplasia,Silverman-Handmaker type: prenatal ultrasound findings and molecular analysis
67.
Stefan Hochrainer-Stigler Adriana Keating John Handmer Monique Ladds 《Environmental Hazards》2018,17(5):418-435
This paper explores sovereign risk preferences against direct and indirect natural disasters losses in industrialized countries. Using Australia as a case study, the analysis compares expected disaster losses and government capacity to finance losses. Utilizing a national disaster loss dataset, extreme value theory is applied to estimate an all-hazard annual loss distribution. Unusually but critically, the dataset includes direct as well as indirect losses, allowing for the analysis to consider the oft-ignored issue of indirect losses. Expected annual losses (direct, and direct plus indirect) are overlaid with a risk-layer approach, to distinguish low, medium and extreme loss events. Each risk layer is compared to available fiscal resources for financing losses, grounded in the political reality of Australian disaster financing. When considering direct losses only, we find support for a risk-neutral preference on the part of the Australian government for low and medium loss levels, and a risk-averse preference in regard to extreme losses. When indirect losses are also estimated, we find that even medium loss levels are expected to overwhelm available fiscal resources, thereby violating the available resources assumption underlying arguments for sovereign risk neutrality. Our analysis provides empirical support for the assertion that indirect losses are a major, under-recognised concern for industrialized countries. A risk-averse preference in regard to medium and extreme loss events recommends enhanced investment in both corrective and prospective risk reduction in relation to these risks level, in particular to reduce indirect losses. 相似文献
68.
/ The Council on Environmental Quality's (CEQ's) principal aims in implementing the National Environmental Policy Act (NEPA) are (1) to reduce paperwork, (2) to avoid delay, and most importantly (3) to produce better decisions that protect, restore, and enhance the environment. This paper presents four strategies for improving the NEPA process along with tools that can be used to implement each strategy. The tools include guidelines for project management and problem definition, tips for acquiring existing information and identifying issues of public concern, worksheets on how to identify and analyze potential impacts on resources, ideas for enhancing NEPA documents, and a NEPA process checklist. The tools can be used at various stages of the NEPA process and provide a toolbox of guidelines and techniques to improve implementation of the NEPA process by focusing the pertinent information for decisionmakers and stakeholders. KEY WORDS: National Environmental Policy Act; NEPA; Environmental impact assessment; Ecosystem management 相似文献
69.
PaulR. Wolf Terrence J. Keating 《Journal of the American Water Resources Association》1973,9(2):312-319
ABSTRACT Necessary input parameters for studying mixing zone characteristics of thermal plumes are horizontal surface and subsurface water velocities. Using time lapse aerial photography and analytical photogrammetric techniques, movements of drogues in an effluent plume were traced. From these traces accurate velocity vectors were obtained. Photographic coordinates of drogue images were measured using a glass scale. From the photo coordinates and the results of a ground control survey, an analytical solution was made for positions of drogues in the water at known intervals of time. Drogue positions were mapped for selected exposures thereby providing a visual display of velocity vectors in the study area. A rigorous error analysis was performed to determine the validity of the computed results. 相似文献
70.
Martha W. Gilliland Gerald P. Wallin Ronald Smaus 《Journal of the American Water Resources Association》1989,25(1):49-61
ABSTRACT: Nebraska has abundant supplies of high quality surface and ground water. The U.S. Supreme Court decision in 1982, declaring ground water to be an article of commerce, is widely perceived as giving neighboring states easier access to Nebraska water. Some neighboring states, particularly Colorado and Wyoming, are in water short situations. Additionally, current legal restrictions on certain types of transfers within the State could be inhibiting the “highest and best use” of Nebraska's water. Thus, in 1987 the Nebraska Legislature called for the development of a new water policy for Nebraska that would promote the economically efficient use of water, yet protect the environment as well as the rights of individuals (for example, third parties) and the public. Through an interagency study employing an extensive public involvement process, a policy to be recommended to the Legislature in 1989 emerged. The policy revises the basic definition of water rights and transfers and eliminates most of the inconsistencies in the water allocation system by treating most types of water resources, most types of water users, and most locations of use similarly in the permitting process. (The principal exception is the individual irrigator using ground water on the overlying land where overlying land is one government surveyed section; such use is not defined to be a transfer nor is a permit required.) An impact assessment would be required of most new water uses except on site uses of ground water. Compensation measures could be specified as a condition of the permit where appropriate. The permit would be issued only if the benefits of the proposed transfer clearly outweigh adverse effects that could not be avoided or effectively compensated. The policy allows for the sale or lease of “salvaged” water. It calls for the State to facilitate transfers by acting as a clearinghouse for potential buyers and sellers, and it allows the State to sponsor water projects. An annual fee to be paid by many water users, in order to provide a fund for compensation and for state sponsored water projects, was proposed. However, it met with extensive opposition. Thus, the policy recommends only that the Legislature examine potential funding programs and equitable user fees. 相似文献