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排序方式: 共有590条查询结果,搜索用时 281 毫秒
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S. Vaynman R. S. Guico M. E. Fine S. J. Manganello 《Metallurgical and Materials Transactions A》1997,28(5):1274-1276
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烷基水杨醛肟虽然是一种高选择性的铜萃取剂,但单独使用时,萃取相易出现沉淀;反萃时,再生有机相出现乳化物,而且两相分离时间较长.将月桂醇、仲辛醇、壬基酚三种调节剂分别加入到萃取剂中,研究其对烷基水杨醛肟萃取及反萃行为的影响.结果表明,三种调节剂均可以解决上述问题,只是使萃取能力略有降低;壬基酚加入到烷基水杨醛肟中有助于提高铜铁分离系数,可达647. 相似文献
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Richard C. Morey Donna L. Retzlaff-Roberts David J. Fine 《International Transactions in Operational Research》1994,1(3):285-292
One of the focal points of discussion among firms in the service sector concerns the level of service delivered and its value. In the hospital sector, an important aspect of the level of service relates to the level of quality of care delivered. We undertake an empirical study of 300 U.S. hospitals to evaluate their relative ‘service efficiency’ using the techniques of so-called allocative efficiency. This method estimates the potential improvement in service, estimates the ideal cost shares of the various resources, and provides the ‘peer group’ members to which the unit is being compared. Utilizing this information, the method proposed for units to improve involves two chief mechanisms. The first is a reallocation of cost shares among the various resource or input types (e.g. no increase in hospital budget). The second involves adopting the management practices used by peer group members. Over all 300 hospitals, a marked improvement potential was found for well over half. Of the poorest performers there appears to be some indication that a larger cost share was needed for face-to-face contact with patients (nursing) and a smaller share for personnel who do not deal with patients directly (lab technicians, non-physician administrators, etc.). 相似文献
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油脂氢化理论研究进展 总被引:2,自引:0,他引:2
本文从下列几个方面阐明油脂氢化理论的研究状况:(1)氢化机理的研究;(2)氢化反应动力学处理;(3)氢化反应活化能的确定;(4)氢化选择性的研究。 相似文献
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Gilbert Baumslag Benjamin Fine Xiaowei Xu 《Applicable Algebra in Engineering, Communication and Computing》2006,17(3-4):205-217
Several suggestions are presented for developing cryptosystems, both classical and public key, using a combination of combinatorial group theory and linear groups. In particular, the Reidemeister-Schreier rewriting process is used as a one way function. These suggestions raise further questions concerning both implementation and security that are being explored in the thesis of Xu [16]. 相似文献
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J Whittle CJ Lin JR Lave MJ Fine KM Delaney DZ Joyce WW Young WN Kapoor 《Canadian Metallurgical Quarterly》1998,36(7):977-987
OBJECTIVES: The authors describe the relation of provider characteristics to processes, costs, and outcomes of medical care for elderly patients hospitalized for community-acquired pneumonia. METHODS: Using Medicare claims data, Medicare beneficiaries discharged from Pennsylvania hospitals during 1990 with community-acquired pneumonia were identified. Claims data were used to ascertain mortality, readmissions, use of procedures and physician consultations, and the costs of care. The relationship of these measures to provider characteristics was analyzed using regression techniques to adjust for patient characteristics, including comorbidity and microbial etiology. RESULTS: Among 22,294 pneumonia episodes studied, 30-day mortality was 17.0%. After adjusting for patient characteristics, 30-day mortality and readmission rates were unrelated to hospital teaching status or urban location or to physician specialty. Use of procedures and physician consultations was more common and costs were 11% higher among patients discharged from teaching hospitals compared with nonteaching hospitals. Similarly, costs were 15% higher at urban hospitals compared with rural hospitals. General internists and medical subspecialists used more procedures and had higher costs than family practitioners. CONCLUSIONS: Processes and costs of care for community-acquired pneumonia varied by provider characteristics, but neither mortality nor readmission rates did. These differences cannot be explained by clinical variables in the database. Further studies should determine whether less costly patterns of care for pneumonia, and perhaps other conditions, could replace more costly ones without compromising patient outcomes. 相似文献
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介绍了利用北京正负对撞机(BEPC)同步辐射X射线光刻装置,进行LIGA工艺技术深结构光刻实验研究,详细论述了X射线光刻使用的掩模制备过程及掩模镀金工艺,在国内最早曝光出直径为400μm、厚为27~45μm的三维立体齿轮胶图形。 相似文献