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991.
Attempted to replicate an earlier study investigating cultural differences between Cuban immigrants and Anglo-Americans. Whereas the earlier study used a nonclinical adolescent population, the current study used 52 adults in outpatient treatment. Ss were given a biographical questionnaire and the Value Orientation scales. Results indicate that the groups differed in relational, temporal, and person–nature orientations, confirming previous findings and clinical observations. (3 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
Comparison of different advanced oxidation process to reduce toxicity and mineralisation of tannery wastewater. 总被引:1,自引:0,他引:1
Many organic compounds contained in wastewater are resistant to conventional chemical and/or biological treatment. Because of this reason different degradation techniques are studied as an alternative to biological and classical physico-chemical processes. Advanced Oxidation Processes (AOPs) probably have developed to become the best options in the near future. AOP while making use of different reaction systems, are all characterised by the same chemical feature: production of OH radicals (*OH). The versatility of AOPs is also enhanced by the fact that they offer different possibilities for OH radical production, thus allowing them to conform to specific treatment requirements. The main problem with AOPs is their high cost. The application of solar technologies to these processes could help to diminish that problem by reducing the energy consumption required for generating UV radiation. In this work, different AOPs (O3, TiO2/UV, Fenton and H2O2/UV) were examined to treat tannery wastewater or as a pre-treatment step for improving the biodegradation of tannery wastewater, at different pH and dosage of the chemicals. Under certain circumstances retardation in biodegradation and/or an increase in toxicity may be observed within these treatment steps. Two different bioassays (Daphnia magna and Vibrio fischeri) have been used for testing the progress of toxicity during the treatment. In parallel other objectives were to analyse and identify organic compounds present in the untreated wastewater and arising degradation products in AOP treated wastewater samples. For this purpose substance specific techniques, e.g., gas chromatography-mass spectrometry (GC-MS) in positive electron impact (El(+)) mode and atmospheric pressure ionisation (API) in combination with flow injection analysis (FIA) or liquid chromatography-mass and tandem mass spectrometry (LC-MS or LC-MS-MS) were performed. 相似文献
993.
Juan J. Aróztegui José J. Urcola Manuel Fuentes 《Metallurgical and Materials Transactions A》1989,20(9):1657-1668
Commercial electric arc melted low-carbon steels, provided as I beams, were characterized both microstructurally and mechanically
in the as-rolled, copper precipitation, and plastically pre-deformed conditions. Inclusion size distribution, ferrite grain
size, pearlite volume fraction, precipitated volume fraction of copper, and size distribution of these precipitates were deter-mined
by conventional quantitative optical and electron metallographic techniques. From the tensile tests conducted at a strain
rate of 10-3 s-1 and impact Charpy V-notched tests carried out, stress/strain curves, yield stress, and impact-transition temperature were
obtained. The spe-cific fractographic features of the fracture surfaces also were quantitatively characterized. The increases
in yield stress and transition temperature experienced upon either aging or work hard-ening were related through empirical
relationships. These dependences were analyzed semi-quantitatively by combining microscopic and macroscopic fracture criteria
based on measured fundamental properties (fracture stress and yield stress) and observed fractographic parameters (crack nucleation
distance and nuclei size). The rationale developed from these fracture criteria allows the semiquantitative prediction of
the temperature transition shifts produced upon aging and work hardening. The values obtained are of the right order of magnitude. 相似文献
994.
The supermolecular structure of crystallised molecular weight fractions of poly(hexa-methylene oxide), covering the molecular weight range (M) 4.5. × 103 to 8. 5 × 104, was studied by polarised light microscopy and small angle light scattering. Different forms were observed as a function of molecular weight and crystallisation temperatures. Perfect spherulites are formed after rapid crystallisation, and these forms deteriorate as both the molecular weight and crystallisation temperature increase. The morphology in the isothermal crystallisation region corresponds to an intermediate state which represents a transition from spherulites to hedrites. 相似文献
995.
The timing, magnitude, and orientation of the escape response from a model predator were examined. A high proportion of the responses were touch-evoked; the lizards responded only immediately after the model contacted them. When the model approached at a higher speed, lizards (Psammodromus algirus) initiated the escape sooner, ran at higher speeds, and escaped to longer distances, but their reactive distances did not vary. Model speed did not affect the escape duration or the directness of the response. Escape trajectories were not random. Responses away from the model occurred more often than responses toward the model, but initial orientation affected the direction of escape trajectories. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
996.
The inhibitory effects on HIV replication of megalomicin (MGM, an inhibitor of intra-Golgi vesicle transport, have been studied. In experiments at low multiplicity of infection on Jurkat and MT2 cell lines. MGM inhibited the production of p24 antigen, the formation of syncytia, and the induction of apoptosis at concentrations below 5 microM. Furthermore, PCR analysis of genomic DNA showed that, in the presence of MGM, HIV-1 had been eradicated from the culture. MGM also inhibited replication of primary isolates of HIV-1 in blood lymphoblasts and more importantly, at 1 microM, MGM inhibited depletion of CD4+ T cells in cultures of blood lymphocytes from seropositive patients. Finally, MGM inhibited the generation of infectious virions and the processing of the envelope protein precursor gp160 to its mature forms, resulting in the rapid degradation of gp 160. These data suggest that MGM induces a powerful inhibitory effect on HIV-1 replication at nontoxic concentrations by preventing the processing of HIV-1 gp160 envelope protein and the subsequent formation of infectious viral particles. 相似文献
997.
This paper describes the theoretical background and the process of obtaining maximum hop lengths and minimum fading margins (if the terminal or repeater locations are fixed) in any region of the world and gives a set of curves providing these characteristics for 1 km with availability of 99.7 % of the time (per 2 500 km), for a given frequency and polarization. Correction factors for other availabilities are also given. 相似文献
998.
Freeston Mark H.; Ladouceur Robert; Gagnon Fabien; Thibodeau Nicole; Rhéaume Josée; Letarte Hélène; Bujold Annie 《Canadian Metallurgical Quarterly》1997,65(3):405
Twenty-nine patients with obsessive-compulsive disorder as diagnosed in accordance with the Diagnostic and Statistical Manual of Mental Disorders (3rd ed., revised; American Psychiatric Association, 1987) who did not have overt compulsive rituals were randomly assigned to treatment and waiting-list conditions. Patients in the treatment condition received cognitive-behavioral therapy consisting of a detailed explanation of the occurrence and maintenance of obsessive thoughts, exposure to obsessive thoughts, response prevention of all neutralizing strategies, cognitive restructuring, and relapse prevention. Compared with waiting-list patients, treated patients improved significantly on measures of severity of obsessions, current functioning, self-report obsessive-compulsive symptoms, and anxiety. When waiting-list patients were subsequently treated, the combined group improved on all outcome measures. Treatment gains were maintained at 6-month follow-up. Results indicate that cognitive-behavioral therapy is effective in the treatment of patients with obsessive thoughts, a group that has often been considered resistant to treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
Slow, intermediate, and ultrafast strain-rate experiments were performed on Ag-20Au (atomic percent) wire samples in 1 M HC1O4, AgClO4, and KCl solutions. Intergranular stress corrosion cracking was found in all of the solutions tested. In the ultrafast strain-rate
experiments, 9.6 s-1, in HC1O4 and in AgClO4 solutions, the size of the cracks proved to be a function of the electric charge circulated before straining. AgClO4 was also found to specifically induce stress corrosion cracking (SCC) in the Ag-20Au alloy. The surface mobility SCC mechanism
was concluded to be the only one that accounted for all of the experimental observations made in the present work. 相似文献
1000.
Digital curve acquisition with a vision system introduces a large amount of degradation. At the same time ‘corners’ convey important visual information. Unfortunately they are found in the same spectral domain as the quantization noise. Low-pass filtering of the curvature function is compared with more sophisticated methods that keep the angles ‘sharp’. An automated inspection is successfully performed, demonstrating the efficiency of a new method. 相似文献