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Species distribution of polymeric aluminium ferrum——timed complexation colorimetric analysis method of Al-Fe-Ferron

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Journal of Environmental Sciences 2001年第4期13卷 418-421页

作者： Hu, YY Tu, CQ Wu, hh S China Univ Technol Coll Paper & Environm Engn Guangzhou 510640 Peoples R China

The effects of the calorimetric buffer solutions were investigated while the two colorimetric reactions of AI-ferron complex and Fe-ferron complex occurred individually, and the effects of the testing wavelength and the pH of the solutions were also investigated. A timed complexatian colorimetric analysis method of Al-Fe-ferron in view of the total concentration of {AI + Fe} was then established to determine the species distribution of polymeric Al-Fe. The testing wavelength was recommended at 362 net and the testing pH value was 5. With a comparison of the ratios of n(Al)/n(Fe), the standard adsorption curves of the polymeric Al-Fe solutions were derived from the experimental results. Furthermore, the solutions' composition were carious in both the molar n(Al)/n(Fe) ratios, i.e. 0/0, 5/5, 9/1 and 0/10, and the concentrations associated with the total ( Al + Fe which ranged from 10(-5) to 10(-4) mol/L..

关键词： polymeric aluminum-ferrum species distribution timed complexation colarimetric analysis method Al-Fe-ferron

The moderating impact of lifestyle factors on sex steroids, sexual activities and aging in Asian men

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Asian Journal of Andrology 2011年第4期13卷 596-604页

作者： Victor hh Goh Terry YY Tong Division of Endocrinology Department of Medicine at David Geffen School of Medicine University of California Los Angeles at Harbor-UCLA Medical Center Torrance CA 90502 USA Department of Obstetrics and Gynecology National University of Singapore Kent Ridge 119074 Singapore

The present study sought to evaluate the relative associations of exercise, sleep and other lifestyle habits with aging, sex hormones, percent body fat （%BF） and sexual activities in men living in the community. A better understanding of this complex interrelationship is important in helping the formulation of modalities for a holistic approach to the management of aging men. The results showed that age is a major determinant for many physiological parameters, including sleep, hormonal and metabolic parameters, some lifestyle factors and sexual activities. Testosterone （T）, bioavailable testosterone （BloT） and dehydroepiandrosterone sulphate （DHEAS） concentrations decreased with age, while estradiol （E2）, sex hormone-binding globulin （SHBG） and %BF increased with age. In addition, there exist intricate associations among hormonal and lifestyle factors, %BF and age. High-intensity exercise and longer duration of sleep were associated with higher concentrations of T and BloT. T was shown to be associated positively with men who were engaged in masturbation. DHEAS was associated with men wanting more sex and with good morning penile rigidity. Older Singaporean men tended to sleep for shorter duration, but exercised more intensely than younger men. Coital and masturbation frequencies decreased with age, and a significantly greater number of younger men were engaged in masturbation. Relationship between the partners is a key determinant of sexuality in men. It appears that T may have a limited, while dehydroepiandrosterone （DHEA） have a greater role than previously suggest, as a motivational signal for sexual function in men. Both biological and psychosocial factors interact with each other to influence sexual functions in men. Hence, a biopsychosocial approach may be more appropriate for a more lasting resolution to sexual dysfunctions in men.

关键词： age Asian men duration physical exercise sex hormones sexual activities sleep lifestyle factors

Cyclic Saturation Dislocation Pattern Observation in the Vicinity of Grain Boundaries by Electron Channeling Contrast Technique

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Journal of Materials Science & Technology 1998年第3期14卷 211-214页

作者： Zhang, ZF Li, XW Su, hh Wang, ZG Acad Sinica Inst Met Res State Key Lab Fatigue & Fracture Mat Shenyang 110015 Peoples R China

The cyclic saturation dislocation patterns within grains and in the vicinity of low-angle grain boundaries in fatigued copper crystal were successfully observed by electron channeling contrast technique in SEM. The results show that the dislocation patterns within grains consisted of typical two-phase structure, i.e. persistent slip bands (PSB) and veins. With increasing plastic strain amplitude (gamma(pl) greater than or equal to 1.7 x 10(-3)), large amount of PSBs and regular dislocation walls were observed. The dislocation walls and PSBs could cross through the low-angle grain boundaries continuously except that the dislocation-free zone (DFZs) appeared at some local regions. Combining with the cyclic stress-strain response and dislocation patterns, the effect of low-angle grain boundaries on cyclic deformation behavior was discussed.

关键词： Copper

Rb-Sr isotope dating of silicalite from the Dajiangping massive sulfide ore deposit,Guangdong Province

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Chinese Science Bulletin 1997年第23期42卷 1983-1985页

作者： Wang, HI Li, HY Wang, YX Wang, hh Nanjing Univ Dept Earth Sci Nanjing 210093 Peoples R China

THE Dajiangping pyrite ore deposit located in the Yunfu County of Guangdong Province is asuper-large pyrite ore deposit. Its age has not been defined so far because of the absence of fos-sil. This note is to use Rb-Sr isotope dating of silicalite to constrain the age of the ore depositand place special emphasis on its geological significance.

关键词： pyrite ore deposit silicalite Rb-Sr isotope ore-forming age.

Assessment of genotoxicity and cytotoxicity of standardized aqueous extract from leaves of Erythroxylum cuneatum in human HepG2 and WRL68 cells line

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Asian Pacific Journal of Tropical Medicine 2013年第10期6卷 811-816页

作者： RK Wesam AN Ghanya hh Mizaton M ILham A Aishah Faculty of Pharmacy Universiti Teknologi MARAShah AlamSelangor Department of Food Sciences and Technology Faculty of AgricultureUniversity of Sana'a Forest Research Institute of Malaysia(FRIM)

Objective:To investigate the cytotoxicity and the genotoxicity of standardized aqueous of dry leaves of Erythroxylum cuneatum(***)in human HepG2 and WRL68 ***:The cytoloxicity of *** extract was evaluated by both MTS and LDH *** study on *** extract was assessed by the single cell gel electrophoresis(comet assay).The protective effect of *** against menadione-induced cytotoxicity was also ***:Results from this study showed that *** extract exhibited cytotoxic activities towards the cells with IC_(50)value of(125±12)and(125±14)μg/mL for HepG2and WRL68 cells respectively,after 72 h incubation period as determined by MTS *** leakage was detected at(251±19)and(199.5±12.0)μg/mL for HepG2 and WRL68 *** study results showed that treatment with *** up to 1 mg/mL did not cause obvious DNA damage in WRL68 and HepG2 *** of *** did not show significant protection towards menadione in WRL68 and HepG2 ***:*** standardized aqueous extract might be developed in onler to establish new pharmacological possibilities for its application.

关键词： Erythroxylum cuneatu Cytotoxicity Genotoxicity DNA damage HepG2 WRL68

The Crystal structure of Hexakisammonium Diacety loctamoly bdate Tetrahydrate

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Chinese Journal of Structural Chemistry 2000年第3期19卷 191-194页

作者： Wang, S Lin, X Lu, CZ Wu, DM Yang, WB Zhuang, hh Chinese Acad Sci Fujian Inst Res Struct Matter State Key Lab Struct Chem Fuzhou 350002 Peoples R China

The title compound, 〔NH 4〕 6〔(CH 3CO) 2(Mo 8O 28 )〕·4H 2O, was produced from (NH 4) 6〔Mo 7O 24 〕·4H 2O aqueous solution in the presence of N 2H 4·H 2SO 4 and its structure has been deter... 详细信息

The title compound, 〔NH 4〕 6〔(CH 3CO) 2(Mo 8O 28 )〕·4H 2O, was produced from (NH 4) 6〔Mo 7O 24 〕·4H 2O aqueous solution in the presence of N 2H 4·H 2SO 4 and its structure has been determined by X ray single crystal analysis. The crystallographic data: C 4H 38 Mo 8N 6O 34 , M r =1481.92, triclinic, P1, a=8.127(2), b = 10\^373(2), c = 12.383(3) , α=99.51(3), β=105.47(3), γ=112.92(3)°, V=883.0(3) 3, Z=1, D c =2.787g/cm 3, F(000)= 712, μ =2.864 mm -1 , Final R =0.0368 and wR =0.0924 for 2926 reflections with I>2σ(I ). The X ray crystal structure analysis reveals that there is one independent molecule in the unit cell of the title compound which contains one centrosymmetric diacetyloctamolybdate anion, six ammonium cations and four water molecules.

关键词： diacetyloctamolybdate centrosymmetric hexakisammonium

КОНТРОЛЪ РАЗРАБОТКИ НЕФТЯНЫХ МЕСТОРОЖДЕНИЙ HА ОСНОВЕ ОCР-СПЕКТРОСКОПH П СТAБHЛЬНЫХ РAДИКАЛОВ

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武汉科技大学学报 1988年第4期 10-16页

作者： H.И.Букпhh

关键词： 110 Ta CT Ho Te 工工 CI HO

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16：0新宽屏来了——你准备好了吗？

微型计算机 2008年第25期28卷 52-59页

作者：撒哈拉hh

备受玩家关注的16：9宽屏LCD显示器终于上市了，想必很多高清影音爱好者都已经等不及了，宽屏显示器现在不是都已经普及了吗？为什么强调16：9比例呢？16：9为什么备受玩家关注？如果你也有以上的问题，请你仔细阅读本文，我们相信会回... 详细信息

备受玩家关注的16：9宽屏LCD显示器终于上市了，想必很多高清影音爱好者都已经等不及了，宽屏显示器现在不是都已经普及了吗？为什么强调16：9比例呢？16：9为什么备受玩家关注？如果你也有以上的问题，请你仔细阅读本文，我们相信会回答你的问题。

关键词：宽屏显示器 LCD显示器市场分析产品

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细胞膜作为肿瘤化疗的靶子

国外医学（肿瘤学分册） 1992年第2期19卷 96-98页

作者： Grunicke hh 董敏

质膜作为现有抗癌药物的靶子目前大多数的抗癌药物是针对DNA的或是干扰核酸的生物合成(例如烷化剂、铂络合物及蒽环类抗生素)。尽管人们对这些药物与DNA的相互作用已很清楚,但对它们抑制肿瘤生长的确切机制尚不甚了解。事实上,在治疗浓... 详细信息

质膜作为现有抗癌药物的靶子目前大多数的抗癌药物是针对DNA的或是干扰核酸的生物合成(例如烷化剂、铂络合物及蒽环类抗生素)。尽管人们对这些药物与DNA的相互作用已很清楚,但对它们抑制肿瘤生长的确切机制尚不甚了解。事实上,在治疗浓度下,这些药物不但可引起质膜结构和功能的改变,也可与质膜相互作用。或许这就是这些药物具有抗肿瘤活性的原因。另外。

关键词：肿瘤药物疗法细胞膜