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41.
作者首次应用不同剂量的丙硫咪唑进行驱除建鲤绦虫试验。用丙硫咪唑20mg/Kg体重驱除建鲤肠道中的九江头槽绦虫,驱虫率达96.5%以上,效果好,安全可靠。 相似文献
42.
采用PCl-812PG数据采集卡,基于虚拟仪器技术,以Delphi作为平台开发了土壤含水量测试系统,对AZS -2土壤水分传感器的功能进行了扩展。标定结果及实际应用表明,此系统性能稳定,精度较高。 相似文献
43.
This paper deals with a single server Poisson arrival queue with two phases of heterogeneous service along with a Bernoulli schedule vacation model, where after two successive phases service the server either goes for a vacation with probability p (0≤p≤1) or may continue to serve the next unit, if any, with probability q(=1−p). Further the concept of multiple vacation policy is also introduced here. We obtained the queue size distributions at a departure epoch and at a random epoch, Laplace Stieltjes Transform of the waiting time distribution and busy period distribution along with some mean performance measures. Finally we discuss some statistical inference related issues. 相似文献
44.
二氧化钛纳米膜制备条件对炼焦厂废水光催化降解性能的影响 总被引:1,自引:0,他引:1
李家其 《湖南人文科技学院学报》2006,(3):28-30
以四氯化钛为前驱体,用溶胶—凝胶法制备了TiO2纳米膜,并进行了炼焦厂废水的光催化降解实验,考察了制备条件对其光催化降解性能的影响。结果表明最佳工艺条件为:四氯化钛∶乙醇∶水=30∶400∶25,溶胶体系pH=7,掺铁量Fe∶Ti=0.16,干凝胶在450℃煅烧2h,由此制成的TiO2纳米膜光催化降解炼焦厂废水的降解率超过79%。 相似文献
45.
韩德艳 《湖北师范学院学报(哲学社会科学版)》1995,(3)
本文用配体置换法合成了烷基钴Schiff碱配合物n—C_3H_ 7Co(salen)(γ—pie)(正丙基·4-甲基吡啶·双水杨醛合乙二亚胺合钴(Ⅱ))。并进行了元素分析、红外光谱、紫外光谱、核磁共振等性质表征。 相似文献
46.
It is shown that when a parameter lying in a sufficiently small interval is to be estimated in a family of uniform distributions,
a two point prior is least favourable under squared error loss. The unique Bayes estimator with respect to this prior is minimax.
The Γ-minimax estimator is derived for sets Γ of priors consisting of all priors that give fixed probabilities to two specified
subintervals of the parameter space if a two point prior is least favourable in Γ. 相似文献
47.
This paper models household fertility decisions by using a generalized Poisson regression model. Since the fertility data
used in the paper exhibit under-dispersion, the generalized Poisson regression model has statistical advantages over both
standard Poisson and negative binomial regression models, and is suitable for analysis of count data that exhibit either over-dispersion
or under-dispersion. The model is estimated by the method of maximum likelihood. Approximate tests for the dispersion and
goodness-of-fit measures for comparing alternative models are discussed. Based on observations from the Panel Study of Income
Dynamics of 1989 interviewing year, the empirical results support the fertility hypothesis of Becker and Lewis (1973).
Received January 7, 1997 /Accepted April 3, 1997 相似文献
48.
Routinely collected computerized data were used to study the process of service delivery in terms of admission patterns, type and quantity of services rendered, and status at termination for whites and nonwhites in two community mental health centers. Social area analysis techniques were employed to control for socio-economic status, ethnicity and life style variables, and an epidemiologic model was used to analyze admission and service delivery rate differences. It was found that nonwhite admission rates were at least twice as great as white rates. Service delivery rates to the population at large were considerably greater for nonwhites than for whites. Delivery of direct services within the centers differed for whites and nonwhites, but no consistent trends emerged when types and amounts of services rendered were analyzed, controlling for sex, ethnicity, age, diagnosis and social area. Disruption of care indices were greater for nonwhites than for whites. Highlighted were some of the complexities involved in interpreting results of utilization studies. 相似文献
49.
Artifact in client satisfaction assessment is discussed and the results of a study of three factors thought to mediate client satisfaction ratings; (a) general life satisfaction, (b) mode of administration, and (c) psychological symptomatology, are reported. A standard client satisfaction questionnaire (CSQ) was modified to yield parallel forms and was administered orally and in writing to 92 clients in two mental health day treatment programs. Satisfaction ratings obtained from these clients were quite similar to out-patient ratings obtained in previous studies conducted in this setting and using the same measures. Oral administration of the CSQ produced 10% higher satisfaction ratings than written administration (p less than .05) and less missing data (p less than .01). Satisfaction ratings were also obtained using a simple graphic instrument. Graphic ratings were comparable to CSQ ratings. Satisfaction with life in general and level of psychiatric symptoms together accounted for 25% of CSQ variance. The implication of these findings for future client satisfaction research is discussed. 相似文献
50.