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991.
Dirkzwager Anja J. E.; Bramsen Inge; Adèr Herman; van der Ploeg Henk M. 《Canadian Metallurgical Quarterly》2005,19(2):217
This study examines secondary traumatization among 708 partners and 332 parents of Dutch peacekeepers (i.e., personnel who participated in military actions implemented by international organizations such as the United Nations). Partners or parents of peacekeepers with 4 levels of posttraumatic stress symptoms were compared on posttraumatic stress, health problems, the quality of the marital relationship, and social support. In comparison with partners of peacekeepers without posttraumatic stress disorder (PTSD) symptoms, partners of peacekeepers with PTSD symptoms reported more sleeping and somatic problems, reported more negative social support, and judged the marital relationship as less favorable. No significant differences were found for parents. Thus, peacekeepers' stress reactions were related to various problems of their partners. A systemic approach to the treatment of persons with PTSD appears appropriate. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
992.
993.
Synthesis and isolation of epoxy secondary amidesvia direct amidation ofVernonia galamensis seed oil
Kent A. A. Bryant Chukwuma P. Nwaonicha Mahmoud Hassan Melissa A. Anderson Folahan O. Ayorinde 《Journal of the American Oil Chemists' Society》1993,70(5):457-460
Vernonia galamensis oil, containing naturally epoxidized triglycerides, was reacted withn-butylamine,n-pentylamine andn-hexylamine to afford high yields of epoxidized secondary amides. Three reaction conditions were investigated: (i) reflux
with amines as solvents, (ii) reflux with hexane as the solvent and (iii) room temperature with the amines as solvents. Reactions
with amines as refluxing solvents were completed in 1–5 h, while those with hexane went to completion within 2 to 5 d. Room
temperature reactions were onlyca. 80% complete after several days. Reactivity was increased with higher amine homologs at both reflux and room temperature
reaction conditions. Isolated yields of epoxy-containing amides were about 80% with purity exceeding 96% in all cases. Spectroscopic
characterization of the previously unreported alkyl-vernolamides is provided. 相似文献
994.
995.
小方坯连铸机二冷系统数学模型的开发与应用 总被引:2,自引:1,他引:1
针对德马克小方坯连铸机存在拉速低、溢漏钢率高、铸机与转炉生产周期不匹配等问题,进行分析和改造。开发了二冷水自动控制静态模型并应用于生产,实践取得提高拉速,降低溢漏率,改善铸机和转炉匹配的好效果。 相似文献
996.
Eric S. Windsor Robert A. Carlton Greg Gillen Scott A. Wight David S. Bright 《Journal of research of the National Institute of Standards and Technology》2002,107(6):663-679
Copper oxide has been detected in the copper containing alloys of NBS Standard Reference Material (SRM) 482. This occurrence is significant because it represents heterogeneity within a standard reference material that was certified to be homogeneous on a micrometer scale. Oxide occurs as elliptically to spherically shaped precipitates whose size differs with alloy composition. The largest precipitates occur in the Au20-Cu80 alloy and range in size from submicrometer up to 2 μm in diameter. Precipitates are observed using light microscopy, electron microscopy, and secondary ion mass spectrometry (SIMS). SIMS has demonstrated that the precipitates are present within all the SRM 482 wires that contain copper. Only the pure gold wire is precipitate free. Initial results from the analysis of the Au20-Cu80 alloy indicate that the percentage of precipitates is less than 1 % by area. Electron probe microanalysis (EPMA) of large (2 μm) precipitates in this same alloy indicates that precipitates are detectable by EPMA and that their composition differs significantly from the certified alloy composition. The small size and low percentage of these oxide precipitates minimizes the impact that they have upon the intended use of this standard for electron probe microanalysis. Heterogeneity caused by these oxide precipitates may however preclude the use of this standard for automated EPMA analyses and other microanalysis techniques. 相似文献
997.
The production of consistent high purity materials is critical for improvement in performance and sensitivity of II-VI photovoltaic
and photoconductive devices. Information regarding the energy band structure and impurity or defect levels present in the
material is essential to understand and enhance the performance of current detectors along with the development of future
novel devices. Secondary ion mass spectrometry (SIMS) is capable of providing information of purity, junction depths, dopant
distribution, and stoichiometry in the material. SIMS techniques can achieve high detection sensitivities in very small analytical
volumes and for a wide range of elements (almost the entire periodic table). SIMS analysis also provides unique capabilities
for localizing atomic distribution in two and three dimensions. Ion images can be obtained by registering the positions of
mass selected ions formed in the sputtering process. The combination of excellent detection sensitivity, high mass resolution,
depth profiling capability, and high resolution image acquisition on a wide spectrum of elements by a SIMS instrument is not
matched by any other instrumentation technique. 相似文献
998.
Yao Jun Fan Jian ren Zhang Xin yu Cen Ke fa Department of Engergy Engineering Zhejiang University Hangzhou China 《水动力学研究与进展(B辑)》2001,(2)
1 . INTRODUCTIONThegas particleflowincurvedductshavebeenwidelyappliedinengineering .Research[2 ] showsthattheerosionefficiencyofbendis 5 0timeshigherthanthatofstraightpipe .Therefore ,improvingtheabilityofbenderosionprotectionisanurgenttask .Thepreviousresearc… 相似文献
999.
1000.