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101.
Feedback provided to Ss and 3rd parties from intra- and extramural investigators following the completion of research involving an agency's clients or staff is described. Ss were from the division of a public health department that provides mental health and substance abuse services in a city with 740,000 people. The division's research requirements include submission of annual progress reports and final reports. Of 135 studies conducted over 12 yrs, annual reports were received from 37% of investigators, and final reports from 30%. There were no significant differences based on investigator discipline or affiliation. Professional and ethical implications are discussed, including adequacy of professional training, the need for mechanisms to ensure compliance with ethical standards, the obligations of clinic directors, and the impact on public academic liaison programs. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
102.
随着信息产业的飞速发展,高频信号设备,如高速计算机、移动电话、卫星通信等,都已从兆赫频段扩展到千兆赫,这就意味着对它们所用的微波电路基板提出了更高的要求.长期以来,高频微波基板几乎没有越出使用聚四氟乙烯的老传统,但是,它有若干缺点玻璃化温度低,故刚性差;加工复杂,故成本高;金属化孔镀层与孔壁的结合力弱,故可靠性不高. 多年来,美国GIL科技公司一直在研制替代聚四氟乙烯的材料,经过姐妹公司的合作,终于研制成功了TPA板材,这种材料克服了上述缺点,从而获得了美国专利.本文介绍了TPA层压板的电气特性、机械特性和热效应,给出了许多宝贵数据.  相似文献   
103.
104.
Many companies are using Just-In-Time (JIT) control systems in their mixed-model multi-level production facilities. When scheduling these facilities the most important objective is to keep a constant rate of usage for every part used by the system. In this paper a mathematical model for scheduling these facilities is studied and techniques for determining good schedules are developed. Procedures for solving very large problems are given.  相似文献   
105.
We present a characterization of some processes affecting the performance of solid state array cameras designed for ground based astronomical imaging in the 8–13μm atmospheric window. Our discussion includes a novel model for electron-hole generationrecombination noise based on the probable pathlength of an electron in a photoconductor. We use the Berkeley mid-IR Array Camera as an example. For this camera, the results show that the total optical system composed of the camera, a 3m telescope, and the atmosphere has an efficiency of about 3%, a 1σ noise equivalent flux density of 25 mJy min?1/2arcsec?2 measured over a Δλ/λ=10% band width, and a noise equivalent expressed as the ambient temperature thermal black body noise of 23%.  相似文献   
106.
Diamond and BN have common relatively soft precursor structures that are hexagonal. Electronic structure calculations have now revealed subtle energy differences between the two materials. Another hard material, stishovite, also has a relatively soft precursor phase, quartz, and here again electronic structure calculations have given insight into the nature of the phase transformation. On the other hand, with boron-related materials, the main focus is to connect basic icosahedra structures to produce a hard material. The structural aspects of these materials are examined and possible consequences for low- and high-coordination ultrahard nitrides considered.  相似文献   
107.
Aqueous extracts of the coralline red algaeBossiella orbigniana have been shown to catalyze the enzymatic oxidation of arachidonic acid to a previously unreported ω6 eicosapentaenoic acid product. This unique fatty acid contains a conjugated tetraene with absorption maxima at 293, 306, and 321 nm, and was identified by spectral methods as 5(Z),8(Z),10(E),12(E),14(Z)-eicosapentaenoic acid. The compound was given the trivial name bosseopentaenoic acid. Under experimental conditions, production of bosseopentaenoic acid was linear up to 2 hr and dioxygen was consumed. Bosseopentaenoic acid, along with several other conjugated tetraenes, was also present in the algae endogenously as revealed by a comparison of the ultraviolet (UV) spectra and the high-performance liquid chromatographic (HPLC) pattern of the purified product and the organic extract ofBossiella.  相似文献   
108.
N‐(4‐Acetoxyphenyl) maleimide (APMI) and three kinds of comonomers bearing a trimethylsilyl group were copolymerized at 60°C in the presence of azobisisobutyronitrile (AIBN) as an initiator in 1,4‐dioxane to obtain the three IP, IIP, and IIIP copolymers. These copolymers were removed from the acetoxy group in a transesterification process into new IVP, VP, and VIP copolymers with a pendant hydroxyl group. Two modified processes were adopted to prepare photoresists using these copolymers. The first process involved mixing the dissolution inhibitor, o‐nitrobenzyl cholate, with the new copolymers. Second, o‐nitrobenzyl cholate was introduced into the copolymers using 1,8‐diazabicyclo[5.4.0]undec‐7‐ene (DBU) in dimethylformamide (DMF). The cyclic maleimide structure is responsible for the high thermal stability of these copolymers. After irradiation using deep–UV light and development with aqueous Na2CO3 (0.01 wt %), the developed patterns showed positive images and exhibited good adhesion to the silicon wafer without using any adhesion promoter. The resolution of these resists was at least 0.8 μm and an oxygen‐plasma etching rate was 1/5.3 to that of hard‐baked HPR‐204. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2791–2798, 2002; DOI 10.1002/app.10255  相似文献   
109.
This article presents a comparative analysis of contemporary printed wiring assembly (PWA) batch manufacturing systems employing surface mount technology (SMT), This analysis is accomplished by reviewing a typical case study of PWA manufacturing system in the USA. A previously developed model is then applied to the system to predict the cost and performance in the production of typical PWA designs. Various modifications to the system are then proposed and evaluated. From the case study, conclusions concerning optimum manufacturing system configuration for this industry can be drawn and are presented.  相似文献   
110.
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