首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   12篇
  免费   0篇
化学工业   1篇
机械仪表   1篇
轻工业   8篇
一般工业技术   2篇
  2023年   1篇
  2007年   1篇
  2004年   2篇
  1984年   1篇
  1981年   1篇
  1979年   2篇
  1978年   1篇
  1977年   1篇
  1975年   1篇
  1957年   1篇
排序方式: 共有12条查询结果,搜索用时 15 毫秒
1.
The magnetic and magnetostrictive properties of cobalt and nickel ferrite were investigated. Sample making and testing procedures are described. A method of evaluation of a biased magnetostrictive transducer is demonstrated. A comparison is made between nickel metal and nickel ferrite which shows that the ferrite may compare favorably for some applications.  相似文献   
2.
3.
4.
Experience in a large manufacturing unit showed that splashes of undiluted shampoo only produced transient effects in the eyes of production and packaging staff; over the same period, very few complaints of eye irritation were received from shampoo users, none of which were of a serious nature. Predictive testing is needed to make sure that new formulations are not severe eye irritants though rabbit eye testing may tend to exaggerate the likely human response. Detergent concentration is the principal factor influencing findings in the rabbit eye and an active matter content of 2.5–3.0% (usually representing a 20% aqueous dilution of shampoo) gives the best discrimination between formulations whilst producing no signs of distress in the animals; for typical anionic shampoos, testing at this concentration is recommended, without subsequent rinsing. Rabbit eye tests should never be conducted at higher concentrations until their innocuousness at 20% dilution has been shown and, even then, stronger preparations should only be instilled if they contain new ingredients for which the potential risk in human use are unknown. Conduct of all rabbit eye testing as a comparison with a ‘control’ formulation of equivalent concentration, known to be well tolerated under market conditions, is recommended. For preliminary screening, an in vitro test using freshly-isolated buccal mucosa cells from human volunteers may be useful, irritancy being assessed by the proportion of cells showing loss of visible nuclei when examined by phase-contrast microscopy. Evaluation de l'irritation oculaire par les shampooings  相似文献   
5.
Direct quality indicators of cowpea paste and akara produced from traditionally wet‐milled peas, and hammer‐milled (dry‐milled) and freeze‐dried (wet‐milled) meals were examined in this study. Both meal samples studied were formulated to consist of 65% medium‐sized particles and 35% large particles by weight. Particle volume mean diameters (µm) of the three paste samples were not significantly different from one another at the various stages during akara production. Scanning electron micrographs of akara crumb were converted to threshold images and analyzed. There was no significant difference in the amount of air found in the akara samples. Akara produced from both meals was found acceptable by sensory panelists with no significant difference in any of the attributes or overall liking among the three samples.  相似文献   
6.
To study the effect of pH on dietary fiber components of vegetables, beans, cauliflower, potatoes, peas and corn were cooked in buffers of pH 2, 4, 6, and 10. Water-soluble pectin and hemicellulose, water-insoluble pectin and hemicellulose, cellulose and lignin were quantitated in raw, cooked vegetables and cooking medium. Tenderness and pH of raw and cooked vegetables were determined. Texture varied with cooking medium. Cooked vegetables were most firm at pH 4 and softest at pH 10. Dietary components found in cooking medium reflected these textural changes. Vegetables which showed greater pH effects exhibited greater changes in fiber components.  相似文献   
7.
Although the role of micro-organisms located on the surface of the scalp is disputed by some authors, lipolytic organisms within the hair follicle may still be implicated in the causation of dandruff. Scale formation appears to be an adaptive response to threshold scalp irritation, taking the form of minimal parakeratosis possibly induced by products of lipolysis permeating thin regions of the horny layer. No single pathogen is yet clearly identifiable but effective anti-dandruff compounds display good antimicrobial activity against the typical lipolytic scalp microflora; this activity is retained in the presence of sebum and a feature of the most efficacious anti-dandruff agents is their good substantivity to the epidermal horny layer.
L'action des produits capillaires sur les pellicules  相似文献   
8.
Together the departments of engineering and English designed and implemented a course sequence that sustains first‐year enrollment in engineering while teaching engineering design and fundamental communication skills. The sequence integrates the goals of four formally separate courses: Critical Reading and Writing, Argument and Research, Engineering Concepts I and II. Linking the courses did not detract from the original course goals nor burden the limited time resources of the participating faculty. We found that the linked courses have increased our first to second year retention rate by up to 30 percent.  相似文献   
9.
10.
Nanotechnology is an inherently interdisciplinary field that has generated significant scientific and engineering interest in recent years. In an effort to convey the excitement and opportunities surrounding this discipline to senior undergraduate students and junior graduate students, a nanotechnology engineering course has been developed in the Department of Materials Science and Engineering at Northwestern University over the past two years. This paper examines the unique challenges facing educators in this dynamic, emerging field and describes an approach for the design of a nanotechnology engineering course employing the non‐traditional pedagogical practices of collaborative group learning, interdisciplinary learning, problem‐based learning, and peer assessment. Utilizing the same nanotechnology course given the year before as a historical control, analysis of the difference between measures of student performance and student experience over the two years indicates that these practices are successful and provide an educationally informed template for other newly developed engineering courses.  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号