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1.
用ICP研究鹿科动物骨质疏松症的微量元素特征   总被引:1,自引:0,他引:1  
鹿科动物的骨质疏松症是近几年出现的一种疾病,它影响鹿的生长发育和繁殖,病重者死亡。我们采集梅花鹿和白唇鹿的毛,血样,用低温灰化方法和温法消解处理样品,用ICP分析了毛,血清中微量元素的含量。病梅花鹿毛样中Mg,Al,Ca,Ti,Fe,Cu,Zn的含量比正常组高,Ti,Cu,Zn的偏差率大于15%,而Si,Mn,P,P,Ag,Ba,La,Ce,Pb比正常组低,V,Ag,Ba,La,Ce,Pb存在...  相似文献   

2.
《天然气化学杂志》2006,15(4):I0007-I0008
A G Abdullah,Zalizawati,247 Ah6n,Vfotor R.,307 Alavi,S.M.,327 Amin,Nor Aishah Saidina 191,259,340 Ammasi,Sriraj,191 An,G的jun,127 Anggoro,Didi Dwi,340 Ge,Zhonghua,164 Gu,Y.,73 Guo,Bo,223 Guo,Jianjun,52 Guo,Xiaohui,105 H B Bai,Liang,105 Bakar,W.Azelee W.Abu,259 Bao,Xinhe,181 Batuev,Lubsan,149 Burgina,Elena,149 Ha£axlioglu,P.,73 Han,Huajun,303 Hong,Kong Bee,266 Hu,Xiaofang,58 Hu,Xi加jun,100 Huang,Shengjun,93 Huang,Xingyun,3…  相似文献   

3.
环酮的构象研究进展   总被引:1,自引:0,他引:1  
王明安  张宁  王道全 《有机化学》2003,23(7):619-627
综述了30多年来环酮(n=8,9,10,11,12,13,14,15,16)及对称的偶数 环二酮(n=8,10,12,14,16,18,20,22,24,26)的构象研究进展。  相似文献   

4.
利用火焰原子吸收法测定了中国银行韶关节市分行458名职工头发中Cu,Fe,Zn,Ca含量,运用统计学方法求出该人群中正常者与白发,脱发者Cu,Fe,ZnCa的特征含量,通过数据比较可看出,白发者Cu,Fe,Zn,Ca的含量均低于正常组,而脱发者与正常组较接近,经相关性检验,证明了Cu,Fe,Zn,Ca偏低的血发存在的相关性,与脱发没有相关性,经过性别比对,女性发中Cu,Fe,Zn,Ca含量均高于男  相似文献   

5.
营养合剂是由胎盘水解的复方氨基酸,中药当归,白术,黄芪的水提液,微量元素Fe,Zn,Cu,蜂蜜及甜菊甙等精制成的高级营养液,本文报道其制备,质控及临床应用,临床应用表明,本品对缺铁性和妊娠性贫血,异食癖,异食癖,顽固性厌食及孕妇小腿痉挛等疗效显著,治愈率分别为92.3%,90.0%,92.0%,93.3%,100%,有效率皆为100.0%,本品营养丰富,疗效可靠,毒副作用小,制备工艺简单,值得临床  相似文献   

6.
固体物理、固体化学与新材料424Tin'",YP"共掺ZBLAN玻璃中的能量传递与转换,冯衍等,物理学报,1997,46(12),2454.425LqO。基导电白瓷高祖电用率的国试和研究,李友芬等,中国有色金属学报,1997,7(l),159.4M环氧树脂粘结SIDZFq,N。磁体的矫顽力机理,于申军等,磁性材料及器件,1997,28(l),16.427SmZFq7Nyq稀土永巴材料的最近进展,吴安国,磁性材料及器件,1997,28(l),46.428重稀土锰基化合物Gd(回n,Co)St的结构与殓性,林钢等,磁性材料及器件,1997,28(2),19.4N制粉过程对SwFq,N。各向异性…  相似文献   

7.
经过两步反应,不经色层分离,制得了较纯净的2,9,16,23-四氨基铜酞菁和1,8,15,22-四氨基铜酞菁两种异构体,采用固相熔融催化法合成中间产物,加快反应速率,改变底物与金属盐的配比为4:1,加适量尿素做溶剂,提高反应产率,在生成产物的还原过程中,以DMF代替水做溶剂,缩短反应时间,提高还原效率,对于产物的提纯,采取对中间产物高度提纯,通过简单的实验操作使还原充分有效,最后采取抽滤的方法,不但可以获得较纯的产物,而且简化了实验操作,对所合成的产物进行了质谱,紫外可见光谱,红外光谱表征,而且简化了实验操作,对所合成的产物进行了质谱,紫外可见光谱,红外光谱表征,质谱表征的结果发现,两种异构体在其DMF溶液中都有二聚现象,而没有三聚或多聚现象,其分子上的氨基具有较强的抗氧化稳定性;紫外可见光谱表征的结果表明,前上的氨基动力学稳定性较强,后随着放置时间的延长,其分子上的氨基有由动力学稳定态逐渐向热力学稳定态转化的趋势,最后形成稳定的分子内氢键。  相似文献   

8.
采用聚丙烯酰胺凝胶电泳技术,研究了含不同浓度的稀土饲料喂养大鼠对大鼠体内9种器官和组织中(心脏,肝脏,肾脏,肌肉,胃,血清,睾丸,胰腺,肺)酯酶酶谱的影响,结果表明:稀土的作用导致酯酶酶谱发生显著的变化,原有的一些谱带消失,出现了一些新的谱带,这种影响随器官和组织的不同而不同,谱带强度的改变也因器官和稀土浓度不同而异。特别是在心,肝,肾,肌,胃中酯酶(EST)同工酶酶谱和稀土的浓度之间具有一定的相关性,对酶活性起着抑制或和激活作用,面对血清,睾丸,胰腺,肺中EST同工酶的影响则相对较小,可见,稀土对大鼠体内酯酶酶谱的影响是广泛而显著的。  相似文献   

9.
对梅州农村饮用水中的重金属元素进行了监测和分析,选择Fe,Mn,Zn,Cu,Ag,Pb,Cd七种元素为检测指标。从实验结果来看,Cu,Ag,Cd含量低,未超标;Fe,Mn,Zn,Pb有超标现象:按其危害程度,Pb,Mn的超标是急需解决的问题。  相似文献   

10.
一种全自动光度滴定仪   总被引:1,自引:0,他引:1  
汪敬武  魏琼雄 《分析化学》1998,26(7):904-908
报道了改装721型分光光度计为光度滴定仪并联用8031单片微机构成一台全自动光度滴定仪,在单片机的控制下,实现取样,加试液,搅拌,开关光门,调零,调参比,滴定,测吸光度,数据处理,显示结果并打印,排除废液,冲洗滴定池等操作过程的全自动化,约110s可完成一次测定,误差〈0.2%,RSD〈1.5%,测定快速,准确,重复性好,可胜任在线监测工作,也可作常规滴定分析。  相似文献   

11.
Poly(hexafluoropropylene oxide), poly(HFPO), networks were prepared from functional polymers by end linking via urethane groups. The prepolymers were characterized by NMR spectroscopy and GPC. The networks were characterized by determination of the number of network chains from the shear modulus, and were snown to contain both trifunctional crosslinks and difunctional links. The properties of the networks were investigated by a range of techniques. Compared with fully-fluorinated networks formed via triazine cross-links, investigated previously, the urethane-linked networks were more readily prepared but were poorer elastomers, were less thermally stable, and were less resistant to swelling by common polar solvents. © 1995 John Wiley & Sons, Inc.  相似文献   

12.
利用密度泛函理论方法研究了IClO2异构化反应机理. 优化得到了七种异构体, 其中OIClO和IClOO还未见报道, 对各异构体的热力学稳定性进行了比较. 找到了异构化过程的过渡态, 并通过内禀反应坐标(IRC)计算确认了各个异构体之间的相互转化关系. 从量子拓扑学的角度, 对典型异构化反应通道IRC途径上的各点进行了电子密度拓扑分析, 讨论了反应过程中化学键的断裂、生成以及化学键的变化规律, 找到了反应途径上的能量过渡态(ETS)和结构过渡态(STS).  相似文献   

13.
云南菊科中草药中铅含量特征分析   总被引:3,自引:2,他引:1  
论述了云南27种菊科中草药及其水提取物中铅含量的特征。菊科植物及水提物中铅含量的频数分布为正偏态,两者的相关系数r=0.09,未呈现显著的线性相关。提取率较高的山紫苑、佩兰、木香铅实际含量低;铅含量高的叶下花、狭叶兔耳风、臭灵丹提取率又较低,减少了人体对Pb的过量摄入。  相似文献   

14.
对烘烤前后南瓜籽中的化学成分进行分析并对比。采用同时蒸馏萃取装置萃取南瓜籽中的挥发性成分,采取超临界CO2萃取技术萃取南瓜籽油脂,并将其分为酸、碱、中性三个部分,用气相色谱-质谱联用方法分析其中化学成分并进行对比。结果表明,南瓜籽挥发性成分中含有多种醛类和酯类化合物,烘烤后产生了大量的烷基吡嗪,其在碱性部分中的相对含量比烘烤前提高14倍多,不饱和醛类化合物含量也有明显提高。南瓜籽油脂中的主要化学成分是油酸、亚油酸及其酯类。还含有生物活性功能成分如植物甾醇、角鲨烯和维生素E等。烘烤后除角鲨烯含量有所降低,维生素E、植物甾醇、亚麻酸等均有提高。  相似文献   

15.
采用溶胶-凝胶法制备了多孔氧化铝膜, 并通过DSC、TGA、SEM、N~2吸附和气体透过率测定等手段, 对膜的性能进行了表征。结果表明, 用这种方法制备的多孔氧化铝膜是一种均匀无裂痕和具有较窄孔径分布(约4nm)的膜材料。将此多孔氧化铝膜制成膜反应器后, 用于甲醇催化脱氢制甲醛的反应, 发现甲醇转化率比常规反应器有较大幅度的提高。同时首次尝试采用溶胶-凝胶法将催化活性组分直接负载到多孔氧化铝膜上, 从而得到了一种具有催化活性的多孔膜, 并考察了它的反应活性。文中对由这两种多孔膜及钯/陶瓷复合膜制成的反应器的特点进行了比较。  相似文献   

16.
High-field asymmetric waveform ion mobility spectrometry (FAIMS) was used to separate gas-phase conformers of bovine ubiquitin produced by electrospray ionization. These conformers were sampled by a triple quadrupole mass spectrometer where energy-loss experiments, following the work of Douglas and co-workers, were used to determine their cross sections. The measured cross sections for some conformers were readily altered by the voltages applied to the interface ion optics, therefore very gentle mass spectrometer interface conditions were required to preserve gas-phase conformers separated by FAIMS. Cross sections for 19 conformers (charge states +5 through +13) were measured. Two conformers for the +12 charge state, which were readily separated in FAIMS, were found to have similar cross sections. Based on a method to calibrate the collision gas thickness, the cross sections measured using the FAIMS/energy-loss method were compared with literature values determined using drift tube ion mobility spectrometry. The comparison illustrated that the conformers of bovine ubiquitin that were identified using drift tube ion mobility spectrometry were also observed using the FAIMS device.  相似文献   

17.
Bacterial proteomes were analyzed by use of electrophoretically mediated microanalysis (EMMA) and field-enhanced stacking. A water-soluble protein fraction was injected onto a capillary. Next, a fluorogenic reagent was injected and allowed to react with the protein mixture, producing fluorescent products that were separated by submicellar capillary electrophoresis and detected by laser-induced fluorescence. By use of a low-ionic strength sample buffer and a brief electrophoretic step, slow moving anionic proteins were stacked at the reagent-sample interface and were preferentially labeled. By reversing the order of sample injection and labeling reagent, fast moving cationic proteins were preferentially labeled. By adjustment of the sample buffer pH, proteins with different isoelectric points were selectively labeled. Electrophoresis fingerprints were generated for the water-soluble protein fraction from six Staphylococcus species. The protein patterns produced were species-specific and were used to construct a phylogenetic tree.  相似文献   

18.
探讨了不同预处理方法对国产玻纤滤筒本底值的降低效果,便于废气样品的分析测定。分别对空白滤筒、热硝酸、硝酸+硫酸和硝酸+EDTA、HCl处理后的滤筒进行分析,测得滤筒中金属元素的含量;对处理效果较好的一批滤筒进行空白加标,考察加标回收率,全程用电感耦合等离子体质谱(ICPMS)法对样品进行测定,结果发现空白滤筒中部分金属元素含量较高;热硝酸处理后,滤筒本底中铅含量有所降低,但其它元素去除效果不显著;硝酸+硫酸处理后,滤筒中铅含量剧增;硝酸+EDTA处理滤筒,铅可以得到较好的去除效果,大部分金属元素含量有了明显降低;基于HCl对金属有较好的溶出效果,浸泡可较好地降低滤筒中金属元素的含量,但大量氯离子存在对ICP-MS法测定的干扰较大。对硝酸+EDTA处理后的滤筒进行空白加标,大部分金属元素加标回收率75%。故以硝酸+EDTA处理玻纤滤筒可以使国产玻纤滤筒适用于废气样品的分析。  相似文献   

19.
A new styryl dye were prepared, 2-[2-(4-dipropylamino-phenyl)-vinyl]-1,3,3-trimethyl-3H-indolium chloride (DPPTVI) chloride. Its infrared and Raman were measured. Quantum chemical calculations were computed for both the isolated and the solute cation. Optimized geometry, atomic net charges were calculated. The calculated vibrational frequencies were scaled to the experimental ones. Only 12 scale factors were used for the scaling of 174 vibrational modes. Based on these results, normal coordinate analysis were carried out for both the isolated and the solute cations. Infrared and Raman spectra were simulated. The results for the isolated and the solute cations were compared.  相似文献   

20.
蔡孟深  曹小冬 《化学学报》1988,46(9):887-894
本文报道了一些取代苯酚的合成, 并探讨了用Grignard试剂合成取代苯酚中酚羟基的保护及脱保护的问题. 利用苄基和甲基作为酚羟基的保护基, 对文献报道的切断醚键脱保护方法进行了评价. 找到了两种新体系能在更温和条件下切断醚键的方法, 指出了它们的适用条件. 实验结果符合硬软酸碱理论.  相似文献   

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