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1.
CCD型束流截面探测器的主要特点是使用电荷耦合器件做传感器,用束流同步光中的可见光成份做为信号源。该探测器同时具有模拟量和数字量两种输出,工作周期短,速度高,不影响束团粒子寿命,在电子储存环物理运行中,是一种有效的探测设备。  相似文献   
2.
Problem-prone behaviors of White American, Mexican American, and American Indian high school dropouts, students in good academic standing, and students in poor academic standing were surveyed. Generally, dropouts were most involved with drugs, perpetration of violence, and victimization by violence, students in poor standing were the next most involved, and students in good standing were least involved. Ethnicity did not interact with academic status, suggesting that differences between dropouts and students were similar across ethnic groups. Some ethnicity and gender main effects were found. Findings were related to R. Jessor's (see record 1992-23064-001) theory of problem-prone behaviors, to peer cluster theory, and to intervention design. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
3.
Survivors of sexual abuse enter psychotherapy with special needs that challenge some of the traditional therapeutic assumptions. The therapeutic relationship, which is the foundation for treatment with abuse survivors, often must shift in nature and quality to address these needs. The main goal of treatment is the integration of self and affective experience. To facilitate this process the authors discuss the establishment and maintenance of an "affective edge" that allows for direct attention to and intervention with the trauma memories and the accompanying affect. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
4.
Comments on the D. Lachar et al (see record 1984-19420-001) evidence of external validity for Personality Inventory for Children (PIC), which is based on correlations of PIC scales with dimension scores derived from factor analyses of behavioral ratings. It is argued that due to considerable item overlap between PIC scales and behavior rating forms, correlations may be an indication of rater reliability rather than one of construct validity. This problem is thought to be especially evident for rating forms completed by parents because parents also completed the PIC, and many items are similar in both content and wording. The problem is illustrated using the hostility/dyscontrol dimension derived from parent ratings. (2 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
Panek  Edwige  Cook  George A.  Cornell  Neal W. 《Lipids》1977,12(10):814-818
Fatty acid and cholesterol synthesis in isolated rat hepatocytes were strongly inhibited by 5-(tetradecyloxy)-2-furoic acid. With either3H2O or [2-14C]acetate as the labeled precursor, the concentrations of inhibitor causing 50% decrease in fatty acid and cholesterol synthesis were, respectively, <0.005 mM and 0.020 mM. At 0.1 mM inhibitor, citrate concentration in cells from fed rats was increased by 75%; lactate and pyruvate concentrations were decreased by 30%; ethanol oxidation was decreased by 20%; with cells from starved rats, the mitochondrial [NAD+]/[NADH] was decreased. Other parameters were unaffected. Both its potency and its specificity indicate that 5-(tetradecyloxy)-2-furoic acid will be useful in studies on the regulation of lipid biosynthesis.  相似文献   
6.
Benzotriazole and its derivatives comprise an important class of corrosion inhibitors, typically used as trace additives in industrial chemical mixtures such as coolants, deicers, surface coatings, cutting fluids, and hydraulic fluids. Recent studies have shown that benzotriazole derivatives are a major component of aircraft deicing fluids (ADFs) responsible for toxicity to bacteria (Microtox). Our current research compared the toxicity of benzotriazole (BT), two methylbenzotriazole (MeBT) isomers, and butylbenzotriazole (BBT). Acute toxicity assays were used to model the response of three common test organisms: Microtox bacteria (Vibrio fischeri), fathead minnow (Pimephales promelas) and water flea (Ceriodaphnia dubia). The response of all the three organisms varied over two orders of magnitude among all compounds. Vibrio fischeri was more sensitive than either C. dubia or P. promelas to all the test materials, while C. dubia was less sensitive than P. promelas. The response of test organisms to unmethylated benzotriazole and 4-methylbenzotriazole was similar, whereas 5-methylbenzotriazole was more toxic than either of these two compounds. BBT was the most toxic benzotriazole derivative tested, inducing acute toxicity at a concentration of < or = 3.3 mg/l to all organisms.  相似文献   
7.
The effects of precursor and calcination temperature on the nano morphology of ruthenium dioxide on titanium, prepared from thermal decomposition of aqueous salt solutions were investigated. Transmission electron microscopy, X-ray diffraction, gas porosimetry and cyclic voltammetry showed that lower calcination temperature yielded smaller crystallites. The crystallites were between 6 and 22 nm in diameter. When using ruthenium nitrosyl nitrate the firing temperature had a large impact on the grain size, but for chloride there was only a minor effect in the temperature range 350-550 °C.  相似文献   
8.
This note shows how elementary decision theory can formally quantify the belief that older plants need not be reinforced to the same levels of seismic conservatism used in new plants.  相似文献   
9.
10.
This paper deals with the experimental construction, stochastic modeling, and statistical signal processing of a novel, artificially constructed biosensor comprised of biological ion channels. Such nanoscale biosensors have been built by incorporating dimeric gramicidin A (bis-gA) ion channels into bilayer membranes of giant unilamellar liposomes, and then excising small patches of the membrane loaded with ion channels. We present a stochastic model for the response of the biosensor and present statistical model validation tests to verify the adequacy of the model. We show that in the presence of specific target molecules, the statistics of the gating mechanisms of the gA channels are altered. By capturing the change in real time, we devise a maximum-likelihood detector to detect the presence of target molecules. To test the sensitivity of this model, we conducted patch-clamp experiments with two compounds known to inhibit conduction of the gA channels. We found experimentally that the real-time detection algorithm was able to accurately identify the addition of the compounds even when the alterations in the patch-clamp recordings were very small. This algorithm provides the sensitive detection system for ongoing development of lipid-based nanosensors.  相似文献   
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