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排序方式: 共有991条查询结果,搜索用时 31 毫秒
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HD Spitz 《Canadian Metallurgical Quarterly》1979,68(1):122-123
A procedure was developed for the quantitative determination of loosely bound water in aluminum chlorohydrate and the water content in denture cleanser effervescent tablets. The basic method involves extracting the water from the sample into dioxane followed by titration of the dioxane in methanol with Karl Fischer Reagent. Matrix Ingredients did not interfere. 相似文献
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R. A. H. Strecker 《应用聚合物科学杂志》1969,13(11):2439-2445
Curing reactions were investigated after the gel point, using infrared transmittance and reflection spectrophotometric techniques. In the system carboxyl-terminated polybutadiene (CTPB)/Epon X801 or Epotuf STF-6, catalyzed with Fe(III)-acetyl-acetonate (FeAA), at an equivalent ratio of carboxyl to epoxide groups, the final extent of reaction of COOH groups was found to be between 64% and 77% for eight CTPB samples. Increasing the ratio of epoxide to carboxyl groups (up to 1.6) resulted in an increase in the conversion, but the complete reaction of COOH groups could not be accomplished. The final extent of reaction also depends upon the functionality of the crosslinking agent. The lower the functionality of the epoxide, the higher the conversion of COOH groups. The use of chromium naphthenate as a catalyst for epoxide–COOH reactions gave higher conversions than FeAA. This result is related to side reactions catalyzed by the chromium naphthenate. The change in mechanical properties and the change in extent of reaction were followed simultaneously; it was found that no further development of mechanical properties occurred when the curing reaction between COOH and epoxide groups had ceased. 相似文献
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HD Moore 《Canadian Metallurgical Quarterly》1977,20(7):566-569
A method of anterior fixation of the bowel in complete prolapse of the rectum is described. The treatment is based on the concept that abdominal pressure should be directed on the bowel against the pubis rather than directly onto the perineum. The results have been universally successful, without mortality and with excellent functional results. 相似文献
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P Ahlers RJ Sullivan WE Hammond EL Walter HD Tolley 《Canadian Metallurgical Quarterly》1976,69(10):1328-1330
When patient records are to be auditied in a program designed to assess the quality of medical care rendered, careful consideration must be given to the cost of the system implemented. Structured data collection and a defined treatment plan are advantageous in facilitating the use of nonphysicians for the majority of the audit. A system using checklists to ensure adequate recording of subjective and objective data and a defined treatment plan for a common symptom complex were implemented by physicians and physician's assistants with a patient load averaging more than 1,000 patient contacts per week in a general medical clinic at Duke University Medical Center. Audit was subsequently accomplished at a cost of 96 cents per record. To reduce this cost, more efficient methods of selecting records for audit should be developed. 相似文献
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