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1.
A method for determining the distribution of cationic shrink-resist resins on wool has been developed. The method is based on a staining technique, using an anionic fluorescent brightening agent (FBA) under specific conditions in which the FBA stains the cationic resin in preference to the wool. When the stained samples are observed under ultraviolet radiation by means of the optical microscope, the areas on the wool fibres where resin is located fluoresce, whereas areas free from resin appear dark. The technique is simple and rapid, and enables the regularity of deposition of cationic resins on wool to be followed when the various parameters which play a role in the pretreatment of the fibre and the application of resins are changed. Regularity of resin deposition is important in the achievement of high levels of shrink-resistance in treated fabrics.  相似文献   
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This review paper contends that by paying attention to the quality of life issues raised by older people, planners may promote better places for all. Recent research in the UK that asked older people to identify quality of life criteria revealed that health, income, social networks, community participation, information, activities, home, neighbourhood and mobility are key areas where old age can be enriched. The paper argues that of these, home, neighbourhood and mobility are paramount for four reasons. Firstly, older people are seen as situated, even fixed, in domestic environments; secondly, society has responded to later life by creating age-segregated spaces; thirdly, lessening mobility may increase the importance of the local arena and fourthly the interplay between the self and the environment underpins or undermines independence. The significance of place means that planners, even more than other professionals, need to be age aware. Drawing on recent national and international research this paper contemplates what a more age-friendly place might be like and considers how issues of age can interact with the broader planning agendas of sustainability, cohesion and liveability to create places that promote well-being for every member of the community.  相似文献   
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The current annual risk of acquiring a foodborne disease in the United States is estimated at 2.7 × 10-2. The risk of associated death is estimated at 3.7 × 10-5. These represent a health care burden >$3 billion. Using a risk assessment model one can identify levels of microbial contamination which may be unacceptable in foods and appropriate controls needed to reduce these levels. Salmonella bacteria continue to represent a large percentage of the identifiable infections. A model developed from human dose-response studies predicts the probability of infection for Salmonella at 7.5 × 10-3 with exposure to a single CFU of the organism. Risks of severity (hospitalization), mortality, reactive arthritides, and mortality in the elderly are estimated at 3.1 × 10-6, 7.5 × 10-6, 1.7 × 10-5, and 2.8 × 10-4. Exposure to microbial contaminants needs to be evaluated on a single meal basis. For chicken, exposure may range from a single drum stick (38g) to a half broiler (176g) but averages around 80g. For beef between 51 and 85g may be consumed during a single meal. Therefore, methods for monitoring must be able to detect at least 1 CFU/80g. Risks for some pathogenic E. coli are estimated at 1,000 to 10,000 less than Salmonella. Therefore, use of coliforms as indicators needs to be assessed and related to occurrence and survival and regrowth potential of the enteric bacteria of greater public health concern. Because, 20% of the U.S. population may be considered to be in a special population category and at an increased risk of severe outcomes, no more than 20% failure of a standard should be acceptable .  相似文献   
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A new route for the synthesis of long chain N α-acyl- l -α-amino-ω-guamdine alkyl acid derivatives, with cationic or amphoteric character has been established. The general formula of these compounds is shown below.
A physico-chemical and antimicrobial study of these products as a function of the alkyl ester or sodium salt (R), the straight chain length of the fatty acid residue ( x ) and the number of carbons between the ω-guanidine and ω -carboxyl group ( n ) has been investigated.
The water solubility, surface tension, critical micelle concentration (c.m.c.) and minimum inhibitory concentration (MIC) against Gram-positive and Gram-negative bacteria (including Pseudomonas) has been determined.
Dicyclohexylcarbodiimide has been used to condense fatty acids and α -amino-ω-guanidine alkyl acids. In these conditions protection of the ω-guanidine group is not necessary. The main characteristic of this synthetic procedure is the use of very mild experimental conditions (temperature, pH) to form the amide linkage which leads to pure optical compounds in high yield in the absence of electrolytes.
The results show that some structural modifications, particularly the protection of the carboxyl group, promote variations of the surfactant and antimicrobial properties. Only those molecules with the blocked carboxyl group (cationic molecules, where R = Me, Et or Pr) showed a good surfactant and antimicrobial activity. When the carboxyl group was unprotected (amphoteric molecules, where R = Na+) the resulting compounds were inactive.  相似文献   
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The energy consumption of several tomato paste evaporators was monitored to provide baseline data for equipment selection or modification. Daily average performance data are given for single, double and triple effect evaporators. Average daily steam economies for the single effect evaporator ranged from 0.74 to 1.02 and averaged 0.84 compared to a theoretical average of 0.95. Two similar double effect evaporators had average daily steam economies which ranged from 0.79 to 2.03. The average daily steam economy measured was 1.45 while the theoretical average was 1.91. The average daily steam economies for the three triple effect evaporators ranged from 1.66 to 3.06.  相似文献   
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Abstract This work was carried out in order to establish variables which would be useful to estimate the shelf-life of vacuum packaged beef from the Pirenaica breed. This breed is the main source of beef meat in the Spanish West Pyrenees. Two different fresh beef cuts (rib and chuck) samples were evaluated for total fatty acid composition, pH, lipid oxidation (TBA values), total bacterial counts (APC), Enterobacteriaceae counts and by sensory evaluation after 15 and 30 day under vacuum and then after 3 days of display. The variables that contributed to separating the storage periods determining the shelf-life of vacuum packaged beef were TBA, APC, Enterobacteriaceae counts and the sensory variables of color, odor and overall appearance.  相似文献   
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