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21.
本文根据高校后勤服务的特点,引出高校后勤危机和高校后勤危机管理的概念,并在进一步分析了高校后勤危机的诱因、主要特点、特殊性和构建高校后勤危机管理体系的必要性等基础上,提出了构建高校后勤危机管理体系所依据的理念、原则和三个阶段。 相似文献
22.
The Y2O3: Yb3 , Er3 microstructures were fabricated by a hydrothermal method without surfactants.The microstructures structure was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM,KYKY 1000B).The up-conversion luminescence spectra were studied under 978 nm laser diode excitation.In Yb3 and Er3 codoped Y2 O3 microcrystals, the relative intensity of green emission became stronger as the morphology of sample changed from wires to films. 相似文献
23.
Squeeze-film effects of perforated plates for small amplitude vibration are analyzed through modified Reynolds equation (MRE).
The analytical analysis reckons in most important influential factors: compressibility of the air, border effects, and the
resistance caused by vertical air flow passing through perforated holes. It is found that consideration of air compressibility
is necessary for high operating frequency and small ratio of the plate width to the attenuation length. The analytical results
presented in this paper agree with ANSYS simulation results better than that under the air incompressibility assumption. The
analytical analysis can be used to estimate the squeeze-film effects causing damping and stiffness added to the system. Since
the value of Reynolds number involved in this paper is low (< 1), inertial effects are neglected. 相似文献
24.
冲击飞片式无起爆药电雷管试产质量分析 总被引:1,自引:0,他引:1
文中介绍了冲击飞片式无起爆药瞬发电雷管试产的产品质量情况,有关数据表明,它是一种技术工艺比较成熟的雷管换代产品,但废品牢相对较高,需要进一步研究合适的工艺参数来加以控制。 相似文献
25.
文章介绍了宝钢自备电厂在改善锅炉燃烧工况,控制锅炉水冷壁结焦所采取的技术措施,分析了锅炉水冷壁结焦量与锅炉二次再热器烟气出口平均温度的关系,为解决锅炉水冷壁结焦所引发的二次再热器超温爆漏问题提供了依据。 相似文献
26.
To investigate the association of human leukocyte antigen (HLA) with susceptibility and clinical manifestations of sarcoidosis. Fifty-five patients with sarcoidosis were studied by using allele group specific polymerase chain reaction technique (PCR). Our data show that: (1) the gene frequency of HLA-DR5 is significantly increased in patients with sarcoidosis, but that of HLA-DR7 decreased. (2) Gene frequencies of HLA-DR9 and HLA-DR5 are relatively increased in male patients and in patients with stage I and stage IIa, respectively. The results suggest that HLA-DR gene might contribute to the susceptibility as well as to the difference of clinical manifestations in sarcoidosis. 相似文献
27.
Li Xi Zuoyan Peng Wei Fan Kui Guo Gu Jianmin Muyu Zhao Wu Guoqiang 《Materials Science and Engineering: B》1996,40(2-3):147-152
SrMgxTi1 - xO3 nanocrystals (x = 0.1–0.6) were synthesized by the stearic acid gel method. Powder samples were characterized by X-ray diffraction and X-ray photoelectron (XP) spectroscopy. The results showed that the lattice parameter a and the O 1s XP spectrum changed not only with the Mg content x but also with the grain size d of the samples. The conductivity of a thick film specimen fabricated on an aluminium oxide wafer was investigated in a nitrogen—oxygen atmosphere. 相似文献
28.
含氨烷基聚硅氧烷的研究进展 总被引:1,自引:0,他引:1
对含氨烷基聚硅氧烷的研究进行综述,着重介绍含氨烷基聚硅氧烷的种类,性能特点,制备方法及应用等。 相似文献
29.
30.
HH Holcomb DR Medoff PJ Caudill Z Zhao AC Lahti RF Dannals CA Tamminga 《Canadian Metallurgical Quarterly》1998,8(6):534-542
Tone recognition is partially subserved by neural activity in the right frontal and primary auditory cortices. First we determined the brain areas associated with tone perception and recognition. This study then examined how regional cerebral blood flow (rCBF) in these and other brain regions correlates with the behavioral characteristics of a difficult tone recognition task. rCBF changes were assessed using H2(15)O positron emission tomography. Subtraction procedures were used to localize significant change regions and correlational analyses were applied to determine how response times (RT) predicted rCBF patterns. Twelve trained normal volunteers were studied in three conditions: REST, sensory motor control (SMC) and decision (DEC). The SMC-REST contrast revealed bilateral activation of primary auditory cortices, cerebellum and bilateral inferior frontal gyri. DEC-SMC produced significant clusters in the right middle and inferior frontal gyri, insula and claustrum; the anterior cingulate gyrus and supplementary motor area; the left insula/claustrum; and the left cerebellum. Correlational analyses, RT versus rCBF from DEC scans, showed a positive correlation in right inferior and middle frontal cortex; rCBF in bilateral auditory cortices and cerebellum exhibited significant negative correlations with RT These changes suggest that neural activity in the right frontal, superior temporal and cerebellar regions shifts back and forth in magnitude depending on whether tone recognition RT is relatively fast or slow, during a difficult, accurate assessment. 相似文献