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921.
机械产品的绿色设计技术   总被引:4,自引:0,他引:4  
本文通过对机械绿色产品的定义及内涵的描述,提出了机械产品绿色设计的基本方法和绿色设计中的主要内容及技术关键.  相似文献   
922.
The so-called attitude-behaviour-gap of ecology might have changed to a ?producer-people-gap”. In summer 2017 in Germany, the intention of private house-builders to buy an exterior insulation system based on renewable materials was measured as positive, with a mean of 5.2 on a 1–7 Likert scale. But the intentions of professionals were clearly below, e.g. craftsmen, with an average of 3.6 on the same scale – although both groups, the privates and the professionals, judged that there is a clear trend towards such products.

Because of these findings, an additional investigation of management by producers was conducted in autumn and winter 2017/2018, in which a very critical atmosphere towards renewable materials was found. It was analyzed that the managements` attitudes might not be a basic refusal of renewable material in general, but rather a fear of costs of research and development of new products.

A concept was tested, to see if it would be possible to cause an attitude change within the professional key target groups just by applying marketing instruments. Five articles in key media of this market have been published between February and May 2018. In the following evaluation (n = 150) in May 2018 significant effects of the communication have been measured: The intention of decision-makers in craftsmen`s businesses to buy an exterior insulation system based on renewable material rose significantly (0.01 Lv.) from a mean of 3.6 in 2017 to 4.4 in 2018.  相似文献   

923.
The stability of animal societies depends on individuals decisions about whether to tolerate or evict others and about whether to stay or leave. These decisions, in turn, depend on individuals costs and benefits of living in the group. The clown anemonefish, Amphiprion percula, lives in groups composed of a breeding pair and zero to four non-breeders. To determine why breeders accept the presence of non-breeders in this species I investigated the effect of non-breeders on multiple components of the breeders fitness. Non-breeders did not assist breeders in any obvious way. Experimental removal of non-breeders had no significant effect on the survival, growth, or reproductive success of breeders. Experimental removal of one of the breeding pair showed that non-breeders had little effect on the time taken for a widowed breeder to recommence breeding. The results indicate that the presence of non-breeders neither enhances, nor reduces, the fitness of breeders in A. percula. I suggest that non-breeders might modulate their effect on the fitness of breeders, either by reducing the costs they inflict or by increasing the benefits they provide, such that it just pays breeders to tolerate, rather than to evict, them. This study illustrates that animal societies can be stable even when some individuals gain nothing from the association.Communicated by M. Abrahams  相似文献   
924.
中国海岸侵蚀危害及其防治   总被引:13,自引:0,他引:13  
张裕华 《灾害学》1996,11(3):15-21
防治海岸侵蚀是减灾防灾的一项重要内容.本文从海岸侵蚀的产生机理出发,针对其造成危害的侵蚀分布特点加以论述,并给出了应采取的整治对策.  相似文献   
925.
Rising demand for shrimp in the developed nations has helped to foster a dramatic growth in marine shrimp aquaculture, particularly in South America and South Asia. In Thailand, Marine shrimp aquaculture is now an important earmer of foreign exchange. The growth in Production has been achieved through the expansion of the culture area and the adoption of intensive production methods. The conversion of near-shore areas to shrimp culture, however, is proving to have many consequences that impinge on the environmental integrity of coastal areas. This paper reviews the development of Thailand's marine shrimp culture industry and examines the nature of the environmental impacts that are emerging. It then discusses the implications these have for rural poor and the long-term viability of the culture industry.  相似文献   
926.
Two marine bacterial isolates from drill mud cuttings obtained from Agbara oilfield,Staphylococcus sp. andBacillus sp., were cultured aerobically in the presence of varying concentrations (0, 25, 50, and 75 μg/ml) of drilling fluids to determine the effects of concentration of toxicants on their growth. With the exception of Clairsol, Enviromul, and Baroid mineral oil, which had little or no effect, the exponential growth ofBacillus sp. was depressed by all other test chemicals. Additionally, all test chemicals except Clairsol had no effect on lag phase of growth ofBacillus sp. WithStaphylococcus sp. the depressive effect on the exponential phase of growth was shown by almost all test chemicals. There was enhancement of both growth rate and generation times ofStaphylococcus sp. and decrease of those ofBacillus sp. with increasing concentrations of drilling fluids. These results show that while some drilling fluids may be stimulatory or depressive to bacterial growth, others may be without effect.  相似文献   
927.
928.
文章介绍了《水污染防治行动计划》(以下称《水十条》)中针对海洋环境保护的背景情况、重要意义、目标指标、主要内容,从陆海统筹的理念出发,阐述海洋环境污染防治和生态保护的要求。  相似文献   
929.
The biological effects of contaminants in British estuaries and coastal waters have been studied for over 100 years. Until the 1970s. the major pollution impact on estuarine organisms was probably caused by poorly treated sewage which led to severe oxygen deficits and consequent asphyxiation of many water-breathers. However, since the introduction of improved sewage treatment in the last 30 years, a number of continuing impacts have come to light which represent true toxic effects of micro-contaminants. Sublethal changes observed in various bioassays and biomarkers are widespread in both fish and invertebrates, and in the most urbanised and industrialised estuaries, these effects are probably having impacts at the population and community levels. For example, there is good evidence to show that tributyltin from some antifouling paints has not only affected the sexuality and reproductive success of individual estuarine and coastal molluscs, but has also damaged some benthic communities of which molluscs are but a part. Although there are data to show that some contaminant concentrations are now declining, we do not yet have enough data in most cases to decide whether organisms have also begun to recover. This paper reviews the entire field of contaminant effects in UK estuarine and marine waters, focusing especially on the years 1985-2000, and makes some recommendations for future research and monitoring programmes.  相似文献   
930.
南水北调东线工程东平湖水质受水产养殖业影响分析   总被引:1,自引:1,他引:1  
按照国家南水北调水质的要求,以东平湖实际情况为依据,分析水产养殖业对东平湖水质影响。  相似文献   
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