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721.
ABSTRACT. A multiple-outfall system for cooling water disposal which is distributed along the direction of stream flow is analyzed. The results provide a simple method of preliminary design of a cooling water discharge outfall system and for a quick extimate of water quality of a polluted stream. It is shown that a properly designed distributed discharge system is capable of preventing serious pollution due to localized discharge of wastes and waste heat; however, the final design of the discharge system should take into account alternative schemes of waste heat disposal and their economic consequences.  相似文献   
722.
ABSTRACT: Teodoro Ardemans, first post-Renaissance water expert of Spain, recognized problems of ground-water contamination, influence of minerals on water quality, and mutual interference between closely spaced wells. He is also noted for his achievements in architecture and the writing of the first comprehensive building code for Madrid.  相似文献   
723.
Makhov GA  Bazhin NM 《Chemosphere》1999,38(6):1453-1459
A physico-chemical model to describe methane and carbon dioxide emission from lakes was developed. The model describes the emission by diffusion, bubbles and plants. The intensity of the fluxes can be calculated either for total or particular emission in dependence on gas bubbles composition. It was found, that diffusional (Q) and bubble (J) fluxes depend on the methane molar ratio (X) in bubbles as follows: [formula: see text]. The model allows to estimate the role of the methane oxidation by atmospheric oxygen in the total methane flux. It was shown, that the methane oxidation does not influence much methane fluxes to the atmosphere for most of the experimentally observed situations.  相似文献   
724.
Pilgrim NK 《Disasters》1999,23(1):45-65
In November 1989 a major landslide destroyed the link road to the village of Sapni in Kinnaur District of Himachal Pradesh in the Indian Himalaya. Although aware of the risk of further landslide activity, the community has campaigned successfully for reconstruction of the road. Decisions of this kind take place at the local level, through village institutions and open debate, with good feedback between villages and district government authorities. In this way a balance is established between meeting more immediate needs (such as domestic water supply, irrigation, road access) and taking acceptable risks. Using the Sapni landslide as a case study, this paper explores the issue of 'acceptable risk', and looks at the existing strategy for risk and disaster reduction in the district.  相似文献   
725.
The micronucleus test of peripheral blood erythrocytes was used to study cytogenetic stability in bream (Abramis brama L.), perch (Perca fluviatilis L.), roach (Rutilus rutilus L.), and pike (Esox lucius L.) from a eutrophic water body not affected by anthropogenic factors. The dependence of the rate of spontaneous micronucleus formation on fish age was estimated. The effect of natural variation in abiotic environmental factors on the cytogenetic stability of species was analyzed.  相似文献   
726.
Total Quality Management was initially developed to facilitate an ethos of continuous improvement of the production process. It entails both an internal and external focus. The former depends on a cooperative effort among employees at all levels of the organization to analyze work processes, minimize process variance, and thereby maximize productivity. The latter requires close collaboration with suppliers to ensure that raw or processed materials can be readily and efficiently integrated into the production process and constant communication with the end user—the customer—to ensure that the process generates the expected level of quality. Applying TQM to service industry processes is a bit more complex. In addition to having to tailor the TQM approach to the specific service industry, the processes are seldom identical and tend not to lend themselves to the same type of statistical variance analysis that is considered a hallmark of TQM. Nevertheless, numerous case studies have shown that TQM is applicable to the service industry and can help to generate a culture of continuous improvement and enhance customer satisfaction. Environmental site assessments provide a unique challenge to proponents of TQM. Construction, geological, and hydrological characteristics are unique at each site; regulatory requirements differ by jurisdiction; access to historical information is inconsistent; auditors have varying backgrounds; and client needs and expectations differ. Nevertheless, as the American Society for Testing and Materials (ASTM) standard practice gains acceptance as a benchmark for environmental site assessments, the application of TQM practices to this service process becomes more practicable.  相似文献   
727.
Among recent lemmings (D. torquatus from the Yamal Peninsula and D. groenlandicus from Somerset, Bathurst, Melville, and Devon islands), there are populations with archaic sets of morphotypes characteristic of the end of the Late Pleistocene. In some parts of the species range, lemming morphotypes follow the pattern characteristic of the Holocene stage of their evolution. Lemmings with the best developed tooth system live in the Bering Sea sector of the Arctic (Wrangel Island, Chukotka and Alaska). The correspondence of the boundaries of the groups distinguished by odontological traits to the phylogeographic data on mitochondrial DNA (mtDNA) and chromosomal groups is discussed.  相似文献   
728.
Monitoring of A. uralensis populations in Kamenskii raion, Sverdlovsk oblast, in 1992–2002 and in Kaslinskii raion, Chelyabinsk oblast, in 2000–2001 revealed an increase in the proportion and diversity of minor morphogenetic aberrations and abnormalities in the structure of the cranium along the axis of the Eastern Ural Radioactive Trace (EURT). The samples from the southern and northern parts of the EURT (contaminated with 90Sr to 500 and 4 Ci/km2, respectively) were characterized by directed deviations from the control with respect to the frequencies of phenes of nonmetric cranial traits and an increase in the level of their fluctuating asymmetry in young females, which is indicative of epigenetic rearrangements in populations living in a radioactive environment.  相似文献   
729.
Population biology ofMacrocystis integrifolia from British Columbia,Canada   总被引:1,自引:0,他引:1  
Aspects of the population dynamics ofMacrocystis integrifolia Bory were determined from harvested wild populations over a 26-month period and cultivated plants over a 40-month period. Mean wild plant size varied from 0.1 wet kg and two fronds in the winter to 3.1 wet kg and mine fronds in the summer. Plant recruitment probably occurred year-round with recruits making up 20 to 86% of the total population. Plant half-lives, estimated from population data, ranged from 1 to 3 months, with few plants exceedings 2 to 3 years in age. Standing crop ranged from 1.6 plants m-2 and 0.1 wet kg m-2 in winter to 8.3 plants m-2 and 8 wet kg m-2 in summer.  相似文献   
730.
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