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991.
Knowledge of customer requirements (CRs) allows manufacturers to effectively reduce the time-to-market for products and maintain a high-level of quality through customer satisfaction. Acquisition, definition, and decomposition of such requirements is therefore a first step in the product design process and key for successful product development. Of building importance in these requirements is for sustainable or green products. Thus has developed the method of Design for Environment (DFE) in product design process, which calls designers to not only understand CRs for product function, structure and economic attributes, but in social and environmental impacts. Thus, the need for elicit environmental customer requirements (ECRs) from various traditional CRs becomes apparent along with the need to meet those requirements in the design process.In the present paper, initial CRs are decomposed and categorized into functional customer requirements (FCRs), performance customer requirements (PCRs) and ECRs. Such an analysis is made based on the analysis of environmentally friendly products (EFPs), environmentally conscious customers, and the characteristics of their CRs, Furthermore, the decomposing method based on semantic analysis is given along with a developed quality function deployment for environment (QFDE) method. These methods create a shift from initial CRs to DFE oriented technical parameters (TPs). Finally, the acquisition and conversion of CRs of the automatic soybean milk maker in the DFE process is taken as an example to validate and analyze the above-mentioned method.  相似文献   
992.
An incubation experiment lasting 111 d was carried out to study the effect of the addition of three clay minerals (Na-bentonite, Ca-bentonite, and zeolite) to soil derived from sewage sludge on water-extractable and exchangeable forms of four heavy metals (Zn, Cd, Cu, and Ni), as well as on soil organic matter mineralization, microbial biomass C and the release of inorganic N. The addition of clay minerals led to a significant decrease in water-extractable and exchangeable forms of heavy metals. The extent of decrease ranged from 14 to 75% for the water-extractable heavy metals and from 12 to 42% for the exchangeable form over the incubation time, as compared with untreated soil. The reduction in extractability of heavy metals was greater due to the addition of Na-bentonite and Ca-bentonite than that due to the addition of zeolite. Addition of clay minerals did not affect any of the following microbiological parameters in the soil: microbial biomass C, organic C (Corg) mineralization, and metabolic quotient (qCO2), and release of inorganic N during the first 3 weeks of incubation. However, as the incubation period increased, these parameters were significantly increased by the addition of clay minerals, especially by the addition of Na-bentonite and Ca-bentonite. This result is explained by a strong reduction in extractability of heavy metals after the addition of Na-bentonite and Ca-bentonite.  相似文献   
993.
The reactivity of a combustible dust cloud is traditionally characterized by the so-called KSt value, defined as the maximum rate of pressure rise measured in constant volume explosion vessels, multiplied with the cube root of the vessel volume. The present paper explores the use of an alternative parameter, called the maximum effective burning velocity (ueff,max), which also is derived from pressure–time histories obtained in constant volume explosion experiments. The proposed parameter describes the reactivity of fuel–air mixtures as a function of the dispersion-induced turbulence intensity. Procedures for estimating ueff,max from tests in both spherical and cylindrical explosion vessels are outlined, and examples of calculated values for various fuel–air mixtures in closed vessels of different sizes and shapes are presented. Tested fuels include a mixture of 7.5% methane in air, and suspensions of 500 g/m3 cornstarch in air and 500 g/m3 coal dust in air. Three different test vessels have been used: a 20-l spherical vessel and two cylindrical vessels, 7 and 22 l. The results show that the estimated maximum effective burning velocities are less apparatus dependent than the corresponding KSt values.  相似文献   
994.
Most ammonia (NH3) emission inventories have been calculated on an annual basis and do not take into account the seasonal variability of emissions that occur as a consequence of climate and agricultural practices that change throughout the year. When used as input to atmospheric transport models to simulate concentration fields, these models therefore fail to capture seasonal variations in ammonia concentration and dry and wet deposition. In this study, seasonal NH3 emissions from agriculture were modelled on a monthly basis for the year 2000, by incorporating temporal aspects of farming practice. These monthly emissions were then spatially distributed using the AENEID model (Atmospheric Emissions for National Environmental Impacts Determination). The monthly model took the temporal variation in the magnitude of the ammonia emissions, as well as the fine scale (1-km) spatial variation of those temporal changes into account to provide improved outputs at 5-km resolution. The resulting NH3 emission maps showed a strong seasonal emission pattern, with the highest emissions during springtime (March and April) and the lowest emissions during summer (May to July). This emission pattern was mainly influenced by whether cattle were outside grazing or housed and by the application of manures and fertilizers to the land. When the modelled emissions were compared with measured NH3 concentrations, the comparison suggested that the modelled emission trend corresponds fairly well with the seasonal trend in the measurements. The remaining discrepancies point to the need to develop functional parametrisations of the interactions with climatic seasonal variation.  相似文献   
995.
On 17 August 1999 at 3:04 a.m., an earthquake of 7.4 magnitude (Richter scale) struck the Marmara region in Turkey. The city of Adapazari suffered 2,680 fatalities with approximately 5,300 injured. The Israeli Defence Forces (IDF) field hospital arrived at Adapazari, on day four after the quake. The team consisted of 102 personnel. The field hospital acted as a secondary referral centre. A total of 1,205 patients were treated in the field hospital between day four and day 14 of the earthquake. The frequency distribution of the medical problems seen in the field hospital was 32 per cent internal medicine, 13 per cent general surgery including plastic, 21 per cent orthopaedic surgery, 23 per cent paediatric disease, 10 per cent obstetrics and gynaecology and 1 per cent major psychiatric disorders. A mean number of 35 patients per day were hospitalised in the field hospital for between 24 hours to one week. The rapid establishment of the field hospital enabled the local medical facilities to 'buy time' in order to organise and restore surgical and hospitalisation abilities in this disastrous situation.  相似文献   
996.
The kuruma shrimp Penaeus japonicus is widely distributed throughout the Indo-West Pacific. Two morphologically similar varieties, I and II, are recognized from the South China Sea. The two varieties are characterized by different color banding patterns on the carapace, but there are no distinct differences in morphometric traits between them based on measurement of 13 characters. Sequence data and restriction profiles of the mitochondrial genes reveal that these two varieties represent distinct clades, with sequence divergences of about 1% (473 bp) in 16S rRNA, 6–7% (504 bp) in cytochrome oxidase I, and 16–19% (470 bp) in the control region. Analysis of amplified fragment length polymorphism confirms that the two varieties are genetically distinct. We also investigated the geographical distribution of the two varieties in the western Pacific by analyzing specimens collected from Japan and Singapore. Shrimps from Japan and Singapore have been found to belong to varieties I and II, respectively, suggesting that the two varieties have different geographical distribution. Phylogenetic study reveals that the two varieties are more closely related to each other than to the other phylogenetically related Penaeus species. Results from this study suggest the occurrence of two cryptic species in the kuruma shrimp P. japonicus.Communicated by M.S. Johnson, Crawley  相似文献   
997.
In the present study, we investigated to find novel ligands for low molecular weight environmental toxin, microcystin-LR (MC-LR) by using phage display technology. Two random libraries, displaying linear 12-mer peptides and cyclic 7-mer peptides, were screened against the immobilized target respectively. After three rounds of panning, phage clones that recognized microcystin-LR specifically were obtained from both the linear and the constrained libraries, proved by enzyme-linked immumosorbent assays and immunoprecipitation assays. DNA sequencing indicated that peptides displayed on some of the selected clones shared consensus sequences. Compared with traditional methods, this approach provided a cheaper and more rapid alternative to screen specific ligands for microcystin-LR. Moreover, since it is rather difficult to take small molecules as targets of phage display libraries, the success of this experiment expanded the applications of phage display technology, and provided a new avenue to study environmental small molecular toxins.  相似文献   
998.
The primary objective of the IAEA's BIOMASS Forest Working Group (FWG) was to bring together experimental radioecologists and modellers to facilitate the exchange of information which could be used to improve our ability to understand and forecast radionuclide transfers within forests. This paper describes a blind model validation exercise which was conducted by the FWG to test nine models which members of the group had developed in response to the need to predict the fate of radiocaesium in forests in Europe after the Chernobyl accident. The outcomes and conclusions of this exercise are summarised. It was concluded that, as a group, the models are capable of providing an envelope of predictions which can be expected to enclose experimental data for radiocaesium contamination in forests over the time scale tested. However, the models are subject to varying degrees of conceptual uncertainty which gives rise to a very high degree of divergence between individual model predictions, particularly when forecasting edible mushroom contamination. Furthermore, the forecasting capability of the models over future decades currently remains untested.  相似文献   
999.
Xu LH  Lam PK  Chen JP  Xu JM  Wong BS  Zhang YY  Wu RS  Harada KI 《Chemosphere》2000,41(1-2):53-58
Seasonal variations in the level of total microcystins in water samples collected from Donghu Lake and a fish pond in Wuhan, China, were studied between March 1995 and February 1996 using a protein phosphatase inhibition assay involving a radioactive 32P-labelled substrate. The assay is highly reliable and repeatable, and is probably the most sensitive assay for microcystin detection to date. Results of the survey indicated the presence of microcystins in the water samples, and the concentration of microcystins appeared to be related to the degree of eutrophication and water temperature. There is also a correlative relationship between the quantity of microcystins and the abundance of microcystin-producing cyanobacteria (Anabaena and Oscillatoria) in the water bodies over a year cycle. In the present study, the positive detection of microcystins in water bodies having no signs of algal bloom warns of considerable potential threat of these waters to public health.  相似文献   
1000.
Net photosynthesis, dark respiration, and transpiration rates were determined during ozone (O3) exposure for three clones of eastern white pine (Pinus strobus L.) differing in sensitivity to O3. Fumigations for 4 h with 0.10, 0.20, and 0.30 μL/L O3 inhibited net photosynthesis of all three clones. Light transpiration was inhibited in both the sensitive and the tolerant clones and was not affected in the intermediate clone. Recovery of net photosynthesis and light transpiration occurred 1 h after the termination of ozonation, with the degree of recovery depending upon clonal sensitivity to O3 and the O3 concentration used. Dark respiration increased in the O3-sensitive clone only, and dark transpiration was unaffected in all three clones after 4-h exposure to 0.30 μL/L O3. Ozone-induced inhibition of net photosynthesis and stimulation of dark respiration are discussed in relation to clonal sensitivity to O3.  相似文献   
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