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991.
ChunmingWang XingfangWu JieLiu Ning'anXu 《北京科技大学学报(英文版)》2005,12(1):43-47
The free structure of M/A islands in pipeline steel X70 has been studied by transmission electron microscope (TEM). It is shown that the M/A islands are about 1-2 μm in size and distribute at the grain boundary of irregular massive ferrite or acicular ferrite in the microstructure of the steel undergoing TMCP (thermo-mechanical controlled processing). The analysis of diffraction contrast shows that the M/A islands consist of retained austenite and some martensite lamellae different in size and orientation. The microtwinning and midrib exist in the lamella of lenticular martensite, which exhibit the typical character of high-carbon martensite. The influences of TMCP parameters on M/A islands have been studied carefully. With the increase of the cooling speed, the amount of M/A islands decrease slightly and the morphology of M/A islands changes to thin dispersive short bars from thick irregular long strips. 相似文献
992.
Verification, ValidationandAccreditationisusedforensuringappropriatecredibilityofsimulationsys tems, anditisindispensabletothesimulationdevelop mentprocess. VerificationdealswithModeling&Simu lation(M&Scapability, anditensuresthesimulationsystemrealizesalltheuser’srequirementscorrectly.ValidationdealswithM&Scredibilityandensuresthatthesimulationsystemhasappropriatefidelity, tosomeextent, whencomparedwiththerealworld. Accreditati onistheprocessofofficiallyaffirmingthesimulationsystemisa… 相似文献
993.
徐山 《盐城工业专科学校学报》2005,18(4):63-64,83
东汉王符《潜夫论》中的并列复词相当丰富,出现了许多新词新义,然《汉语大词典》存在着对《潜夫论》并列复词未收录的问题;对相关并列复词进行考释。 相似文献
994.
考虑D/A转换器建立时间的影响,建立了D/A转换器输出信号波形的新的时域模型。在此基础上,以正弦信号的发生为例进行了频谱分析。发现了建立过程的平滑作用可以明显地削弱信号的谐波分量,并存在一个最佳转换频率,使谐波失真达到最小值。该结果为D/A信号发生器的优化设计提供了参考依据。 相似文献
995.
通过对MA1420A型万能外圆磨床夹具的改造,在保证原来的加工范围情况下,用最低的成本实现了精轧机导辊的修磨,降低了生产备件消耗,节约了生产成本。 相似文献
996.
No authorship indicated 《Canadian Metallurgical Quarterly》2005,60(8):882
This award recognizes outstanding service delivery by a licensed psychologist who is primarily engaged in the practice of psychology in a private sector setting. The award is intended to recognize outstanding practitioners in psychology. In previous years, this award was called the Award for Distinguished Contributions to Applied Psychology as a Professional Practice. The name was changed in 2003 to better describe this award. Award winners from 1972-2005 are listed. This document includes the citation awarded to Edward A. Wise, winner of the 2005 APA Award for Distinguished Professional Contributions to Independent or Institutional Practice in the Private Sector. A brief biography and a selected bibliography of Wise accompany the citation. Also published here is an address, entitled Effectiveness of Intensive Outpatient Programming in Private Practice: Integrating Practice, Outcomes, and Business (see record 2005-14550-037), which was delivered by Wise at the 113th annual APA Convention. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
The effects of serotonergic agonists were examined in intact and spinal fetuses, using an in vivo fetal rat preparation. On Gestational Day 20, fetuses were prepared with a midthoracic or sham spinal transection. Dose-response curves were obtained for quipazine (nonselective 5-hydroxytryptamine [5-HT] agonist; 1.0-10.0 mg/kg), CGS-12066A (5-HT1B agonist; 1.0-30.0 mg/kg), and α-methylserotonin (α-Me-5-HT; 5-HT? agonist; 0.2-15.0 mg/kg). During a 10-min test, each of the agonists (delivered via intraperitoneal injection) influenced fetal behavior: They increased the occurrence of head movements, mouthing, and hindlimb stepping. Quipazine and α-Me-5-HT also promoted hindlimb activity in spinal fetuses. Thus, stimulation of the fetal 5-HT system modulates motor activity at multiple levels of the developing central nervous system. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
998.
Gels formed by altering α-doped (Np, Pu, Am) SON68 glass at 300 °C were leached during 1 year at 44 cm−1 and 50 °C under oxidizing conditions (Eh/NHE ≈ +150 mV) and under reducing conditions (Eh/NHE ≈ −250 mV). After 3 days of leaching the gel dissolution was highly incongruent. The gel dissolution rate calculated from the silicon concentrations was 4.4 × 10−5 g m−2 d−1, except for the Am-doped gel, for which the rate was two times higher. During leaching, Np is weakly retained in the gel (35% under oxidizing conditions and 50% under reducing conditions) whereas Pu and Am are strongly retained (over 90%). The three lanthanides La, Ce, and Nd exhibit exactly the same leaching behavior, but different from that of actinides. Speciation and complexation calculations for neodymium showed that its solubility could be controlled by Nd(OH)3 for periods beyond 3 months. Conversely, no simple chemical compound appears to control the solubility of the actinides. 相似文献
999.
建立了BP神经网络模型来计算制冷剂物性参数,并以近共沸混合制冷剂R410A为例计算其饱和和过热状态的物性参数值,得到了满意的结果. 相似文献
1000.
SCR技术半固态制浆及组织形成机理 总被引:2,自引:0,他引:2
采用单辊搅拌冷却技术(Shearing-Cooling-Rolling,简称SCR)制备A2017合金半固态浆料,对SCR工艺参数对半固态浆料组织的影响以及组织形成机理进行了研究.结果表明,熔体浇注温度和辊靴型腔高度对半固态浆料组织的影响显著,降低熔体浇注温度或减小辊靴型腔高度,半固态浆料组织从粗大的枝晶和菊花晶转变为细小的等轴晶或球形晶.组织形成机理分析表明,熔体首先在工作辊和靴子表面形核生长,在液流冲击及剪切搅拌的作用下晶核脱落游离进入残余液相区长大成菊花晶,在强烈剪切搅拌作用下,菊花晶断裂破碎最终形成非枝晶组织. 相似文献