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91.
本文介绍了笔者设计的测定AsCL_3在9mol·L~(-1)盐酸—苯相的分配比(D_1)和在水—苯相中的分配比(D_2)的简便方法。试验测知,在19℃时,D_1为10.82,D2为0.0180。苯对9mol·L~(-1)盐酸中的As(Ⅲ)的萃取率为91.5%,水对苯相的As(Ⅲ)的反萃取率为98.2%(等体积一次萃取)。 相似文献
92.
作为一名高等学校教师,应具备的条件是:热爱教育,勇于奉献;严谨治学,提高教师水平;热爱学生,严格而科学地要求学生。同时,还要加强职业道德修养,为教育事业做出应有的贡献。 相似文献
93.
Objective: To construct a PC12 cell strain with neuronal differentiation, and observe the apoptosis and pro-liferation activity effects induced these cells by Amyloid beta-Protein (Aβ-43). Methods: 1) PC12 cells in logarithmicgrowth phase were subcultured for 24 h. After the culture fluid was changed, the cells were treated with Rat-β-NGF andcultured for 9 days. 2) Neuronal differentiation of PC12 cells in logarithmic growth phase were divided into four groups:control group (0), experimental group (1), experimental group (2) and experimental group (3). The concentrations of Aβ inthe four groups were 0 μmol/L, 1.25 μ mol/L, 2.5 μ mol/L and 5 μmol/L, respectively. The cells were harvested at 24, 48 and72 h later and stained with AnnexinV-FITC/PI after centrifugation and washing. Then flow cytometry was conducted toexamine the apoptosis percentage. 3) NGF-induced PC12 cells were selected and Aβ with different concentrations wasadded. The final concentrations of Aβ were 0 μmol/L, 1.25 μmol/L, 2.5 μmol/L and 5 μ mol/L, respectively. After the cellswere incubated in an atmosphere of 5% CO2 at 37 ℃ in an incubator for 72 h, the OD values were examined. Results: 1)Neuronal differentiated PC 12 cell lines were successfully established. 2) Flow cytometric examination indicated that Aβ(1.25, 2.5, and 5.0 μmol/L) could effectively induce apoptosis of neuronal-differented cells at the 24 h, 48 h and 72 h timepoints. 3) Aβ (0-5.00 μ mol/L) had no obvious effect on proliferation or restraining of the neuronal differentiation of thePC 12 cells after a 72 h interacting process. Conclusion: This investigation revealed successful neuronal differentiation of thePC12 cell strain. The induction of apoptosis of the neurocytes by various concentrations of Aβ was observed and the in-fluence of Aβ on induced proliferation of PC 12 cells by Rat-β-NGF was revealed. This study -05 provide basis for futureresearch on the molecular cure of AD and interdiction of AD evolution. 相似文献
94.
唐娜 《南京师范大学文学院学报》2007,(1):24-27
现实生活中,在灾荒之年,人们往往会以松柏为食充饥;而在传统医学文献中,松柏还有治病的功效。魏晋之际,道教迅速发展,贵族与平民分别在自己生活的基础上创造了一些食松柏而成仙的故事,食用松柏成为道教修道成仙的一种方法。 相似文献
95.
Objective: To study the relationship between the size of pontocerebellar angle tumor and audiology. Methods: Retrospective
analysis of accoustically evoked brainstem response (ABR) waveforms and pure tone threshold in 27 subjects with tumor of pontocerebellar
angle. Results: ABR wave forms and pure tone threshold were significantly affected statistically by the size of tumors, especially
those tumor larger than 3 cm in diameter. Conclusion: The primary symptom of the patient was unilateral hearing loss. Early
discovery of the lesion is important and ABR is a sensitive tool for early diagnose of the tumor. 相似文献
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学习型学校是指通过培养教师的自主学习和团队学习,形成学校浓厚的学习气氛,进而充分发挥教师的创造性思维能力,为实现学校的共同愿景而创造性工作的学校。马克思主义哲学是创建学习型学校的哲学依据,彼得·圣吉的学习型组织理论是创建学习型学校的理论依据。新时代对教育“挑战”使我们认识到:创建学习型学校是建设学习化社会的需要,是提高办学水平的需要,是提高教师素质的需要。创建学习型学校应树立现代化的学习理念,营造学习型校园文化,建构灵活高效的学习机制,确立学校共同发展的愿景,建立自主管理机制,构筑学习评价体系。 相似文献
99.
Color control of the multi-color printing device 总被引:4,自引:0,他引:4
WANG Xiao-hua XIU Xiao-jie ZHU Wen-hua TANG Hong-jun 《浙江大学学报(A卷英文版)》2006,7(7):1187-1192
INTRODUCTION During the development of printing technology, digital printing has played an important role. Now various kinds of multi-color digital inkjet printers are available. Compared with the conventional digital inkjet printer, the multi-color digital inkjet printer has larger color gamut and can faithfully produce more colors. The conventional color printing devices nor- mally use three or four inks, e.g., CMY, CMYK. Although some adopt more than four inks, e.g., CMYKLcLm, the… 相似文献
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