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21.
This article is prompted by the remarkable characteristic of nineteenth-century Scotland that circumstances congregate to give an unprecedentedly generous or democratic view of life. Four forms of communication – the statistical accounts, which were followed by the British census records, the boom in publishing, especially in newspapers and journals, and inexpensive communication promoted by the penny post, even the information in street directories and advertisements – all combine with the exploitation of photography to give us insights, which can be disconcertingly specific, acting as occasional spotlights on the landscape. This article is prompted by one particular letter from Robert Louis Stevenson, written when he was a young man, and is followed through two lines of connected thought: the practice of studio photography in Scotland and Stevenson's continuing interest in the photographic portrait.  相似文献   
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The crystallization of [Ga]-MFI was investigated as a function of synthesis time under atmospheric pressure. The molar composition of the reactants was 100SiO2–Ga2O3–11Na2O–11TPABr–3500H2O. The crystallinity of [Ga]-MFI was examined using several analytical instruments, such as XRD, XPS, XRF, FT-IR, solid state MAS-NMR, and DTG/DTA. [Ga]-MFI was successfully synthesized under atmospheric pressure at 97°C in 72 h. It was found that the nucleation of [Ga]-MFI took quite a long time, but the crystallization took place very fast. It is supposed that the nucleation is the rate-controlling step in [Ga]-MFI synthesis under atmospheric pressure. Consequently, if the induction period of the nucleation can be shortened, it would be possible to synthesize [Ga]-MFI commercially under atmospheric pressure.  相似文献   
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The quality of an -tocopherol standard can be checked easily by measuring the UV absorbance at minimum (255 nm,A min) and maximum (292 nm,A max) wavelengths inn-hexane. If the quotientA min/A max exceeds 0.18, the standard contains less than 90% -tocopherol and the determination at 292 nm will yield inaccurate results.  相似文献   
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用宏程序进行椭圆的数控车削加工有两种方法,一种是用直角坐标系,一种是用极坐标系方法,都是用G73进行粗加工,用G70精加工.然而大部分工件毛坯是圆柱型材,G73加工效率低,如果用近似圆弧代替椭圆进行粗加工,用G71粗加工可以提高效率.  相似文献   
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依据数控车床FAN U C系统中G 71固定循环指令在典型工作任务中的案例,在数控专业课编辑教学过程中,针对教学的有效性,运用合理的教学方式,能极大地激发学生学习数控编辑的兴趣,从而全面提高数控专业课的教学品质。  相似文献   
28.
Readers and secondary services are alerted that, through no fault of her own, two nearly identical articles by Denise C. Park have been published. A full report of the research appeared in the American Psychological Association publication, Psychology and Aging. The full reference follows: Park, D. C., Morrell, R. W., Frieske, D., & Kincaid, D. (1992). Medication adherence behaviors in older adults: Effects of external cognitive supports. Psychology and Aging, 7,252-256 (see record 1992-36400-001). Although Dr. Park expressly denied in writing to the conference editors permission to publish the full text of the paper in the conference proceedings, the full text nonetheless was published as follows: Park, D. C., Morrell, R. W., Frieske, D., & Kincaid, D. (1992). Copyright 1992 by the American Psychological Association. Medication adherence behaviors in young and old adults: Effects of cognitive interventions. In H. Bouma & J. A. M. Graafmans (Eds.), Studies in health technology and infomatics: Volume 3. Gerontechnology (pp. 401-406). Amsterdam: IOS Press. Citations to this research should be made, as the author intended, to the primary archival publication in Psychology and Aging. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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利用有限元分析软件对U71Mn重轨轨头淬火过程中的应力场进行数值模拟,并对影响其分布的各种因素进行研究。结果表明,准确选择淬火时加热、保温时间和风冷时的压强,能显著降低轨头的淬火应力,对U71Mn重轨轨头热处理中相关参数的选择具有重要的指导意义。  相似文献   
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目的制备肠道病毒71型(EV71)单克隆抗体,并进行初步鉴定。方法将RD细胞和Vero细胞培养的EV71原液通过氯化铯超速离心纯化,分别作为免疫抗原和检测抗原,制备单克隆抗体。通过Westernblot分析、间接免疫荧光试验和ELISA法鉴定单抗的特异性。采用间接ELISA法测定单抗的酶标效价,微量细胞培养中和试验测定单抗的中和效价。结果获得1株可稳定分泌抗EV71单克隆抗体的杂交瘤细胞株,其分泌的单抗可与EV71特异性结合,酶标效价为1∶204800,中和效价为1∶28。结论已成功筛选出1株分泌抗EV71的单抗细胞株,为建立EV71疫苗抗原含量测定方法奠定了基础。  相似文献   
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