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1.
用ICP-AES方法,对30例大肠癌,26例溃疡性结肠炎进行血清钼,锌,铬铁,铜,锰,铅,铝,硒,铋,钡,钛,钴,钒等微量元素测定,并与20例健康者对照。结果显示大肠癌组血清钼,锌,铬,低于对照组钼,锌,铬,P分别〈0.01,〈0.05,〈0.05;溃疡性结肠炎组钼低于对照组,P〈0.05。提示微量元素代谢异常可能直接影响酶系统,使自由基失控,体内促氧化和抗氧化平衡失调,促使肿瘤的发生。  相似文献   

2.
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   

3.
聚苯乙烯,聚甲基丙烯酸甲酯对聚氯乙烯/氯化聚乙烯共混体流变性的影响杨文君,吴其晔,杜华(青岛化工学院高分子材料系,青岛,266042)王建民,李应华,张宝善(齐鲁石化研究院,淄博,255434)关键词塑料改性,流变性,聚氯乙烯,氯化聚乙烯,刚性粒子我...  相似文献   

4.
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   

5.
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   

6.
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   

7.
中华猕猴桃果实香气成分的GC-MS分析   总被引:9,自引:0,他引:9       下载免费PDF全文
采用溶液萃取法,提取“早鲜”猕猴桃果实中的香气成分,经气相色谱-质谱联机分析,鉴定出45个香气组分,占总峰面积的95.9%,其相对含量,以棕榈酸,辛酸,油酸,3-羟基丁酸乙酯,(Z,Z)-9,12-十八二烯酸,1,2,4-三羟基-(对)-萜烷,(E)-2-己烯醛,1,2-苯二甲酸双(2-甲氧基乙基)酯,硬脂酸,2-己烯醛等为主。  相似文献   

8.
毛细管电泳安培法分析单个神经细胞   总被引:1,自引:1,他引:1  
毛细管电泳安培法分析单个神经细胞胡深,庞代文,王宗礼,程介克(武汉大学化学系,武汉,430072)李之望,樊友珍,胡宏镇(同济医科大学实验医学研究中心,武汉,430030)关键词毛细管电泳,安培法检测,单个细胞分析在生命科学研究中,单个水平的神经细胞...  相似文献   

9.
乙酰丙酮-5,10,15,20-四-(对戊氧基苯基)卟啉及镱配合物的合成与表征李冬梅,刘国发,师同顺,林闽,刘玉文,邹明珠,曹锡章,刘晓勋(吉林大学化学系,长春,130023)(吉林大学分析测试中心)关键词乙酰丙酮,四-(对戊氧基苯基)卟啉,镱的配合...  相似文献   

10.
用可见分光光度法与等离子体发射光谱法对仙人掌果汁色素及其微量元素的含量进行了测定,仙人掌果汁色素含量达2.1% ̄3.3%,成熟果的果汁色素含量比预成熟果大。在27种被测定的元素中,除As、Be、Cd、Co、Mo、Pb,Sb,Tl等未被检出外,其余Ag,Al,B,Ba,Ca,Cr,Cu,Fe,Mg,Mn,Na,Ni,Se,V,Zn,K,P,S等均有准确测定值。成熟果与预成熟果的果汁微量元素含量无明显  相似文献   

11.
The objective of this study is to produce double emulsion by combining polyglycerol polyricinoleate (PGPR) with lecithin as lipophilic surfactant. Although lecithin alone produced only oil-in-water type emulsion, the mixture of lecithin and PGPR could produce water-in-oil type emulsion as well. Moreover, different emulsification treatments were applied to study the influence of homogenization methods on the physicochemical characteristics. The obtained double emulsions were compared in terms of stability and droplet size. It was found that the homogenization method influenced the physiochemical characteristics of the double emulsion and the most stable double emulsion with the smallest droplet size was obtained by high-speed homogenization method.  相似文献   

12.
通过正硅酸乙酯分别在聚甲基丙烯酸甲酯乳液和四氢呋喃溶液中的溶胶-凝胶反应制备出不同的聚甲基丙烯酸甲酯/二氧化硅复合材料。利用扫描电镜、透镜电镜、差热分析和热失重对试样进行了分析。结果表明,利用聚合物乳液可以获得纳米分散的聚甲基丙烯酸甲酯/二氧化硅复合材料,并且在某种程度上其分散尺度小于利用聚合物溶液获得的复合材料。同时,利用聚合物乳液来制备聚甲基丙烯酸甲酯/二氧化硅杂化材料更有利于凝胶过程中二氧化硅网络的形成。  相似文献   

13.
Nickel, iron, and copper were determined in margarine samples by using emulsification followed by inductively coupled plasma-atomic emission spectroscopy. Sample treatment and instrumental conditions were optimized, and the results were compared with those obtained by a pseudodigestion method in order to evaluate the compatibility of both methodologies. The optimum amount of margarine in the emulsion was 35% when the surfactant Tween 80 was added as the emulsifier. Copper was below the detection limits of both methodologies, i.e., digestion and emulsion; iron and nickel concentrations found by both methodologies were similar. The detection limits of the emulsion method were 0.002, 0.015, and 0.092 mg/kg for copper, iron, and nickel, respectively. A benefit of the emulsion method is that laborious and lengthy sample digestion procedures are avoided. In addition, accurate and precise results are obtained. Recoveries with the emulsion method ranged from 101 to 104%, with relative standard deviations of < or = 6%.  相似文献   

14.
In this paper, effect of emulsification processes on the properties of Pickering emulsions stabilized by organomontmorillonites (OMts) was studied. Results of micro-morphology and X-ray diffraction showed that the structure of OMt in emulsion depended on the emulsification processes and had an effect on the stability of emulsion. We propose a schematic diagram to reveal the relationship between emulsification processes-OMt laminates structure-stability of Pickering emulsion. In emulsion prepared by ultrasonic, OMt showed uniform dispersion, loose structure, and irregular crystalline. In emulsion prepared by vortex mixing method, OMt illustrated stacking and coagulation structure. In emulsion prepared by microwave method, OMt showed interacting structure and had a little interaction with oil/water interface, and thus the properties of emulsion prepared by microwave was weakly related to oil/water ratios. Emulsification processes had a profound effect on the structure of OMt and stability of Pickering emulsion, which can be used as a trigger to prepare emulsion for various applications.  相似文献   

15.
本文建立了双波长分光光度法测定乳浊液中烈香杜鹃油的分析方法,烈香杜鹃油含量在0.005~0.8 g.L-1的范围内线性关系良好(R=0.9999,n=9),平均回收率为99.92%,相对标准偏差为1.64%。该测定方法简便快速,结果准确,为性质相似的其它油性药物在乳浊液中含量的分析测定提供了参考。  相似文献   

16.
双丙酮丙烯酰胺参与共聚的聚丙烯酸酯乳液的制备及其应用   总被引:13,自引:0,他引:13  
肼;聚氨酯;乳液性质;交联;双丙酮丙烯酰胺参与共聚的聚丙烯酸酯乳液的制备及其应用  相似文献   

17.
建立了乳状液在重力场和离心力场中的沉降/分层速率模型,利用离心加速乳状液的沉降/分层,根据分层后富水相的电导随离心时间的变化关系得到乳状液在离心场中的稳定时间tc,进而推算出乳状液在重力场中的稳定时间tg。这种离心-电导联用方法可快速评价O/W乳状液的稳定性。例如,以质量分数为4%Pluronic F68、1.2%卵磷脂、8%甘露醇和10%IPM配置的乳状液,在8000r/min离心下测得tc为22min,计算出tg为69d;定性分析得到离心分层常数KA=48.0%,结果表明,该配方可得到稳定的O/W乳状液。  相似文献   

18.
以工业原料α-烯烃磺酸钠(AOS)作为可聚合乳化剂,苯乙烯(St)和丙烯酸丁酯(BA)为单体,采用预乳化种子乳液聚合合成了St-BA-AOS共聚物乳液.通过测定AOS与两种单体的竞聚率确定了半连续加料法的聚合方式.探讨了单体的加料方式、反应温度、反应时间、AOS用量等工艺条件对胶乳的影响,获得了最佳聚合条件.IR,NMR和DSC测试结果分析表明:St,BA与AOS发生了自由基共聚反应,形成的P(St-BA-AOS)共聚物结构中含有磺酸基等亲水性基团有利于乳液的稳定.在此基础上考察了AOS用量对乳液的固含量及乳胶粒粒径等的影响.结果表明:随着AOS用量的增加,乳液的固含量增加、乳胶粒的平均粒径减少.当AOS含量为2%时乳液的固含量为45.01%,平均粒径为74 nm,粒径分布指数为0.08,玻璃化温度为23.17℃.TEM测试结果显示,用相同量的AOS代替十二烷基硫酸钠可得到粒径更小和粒径分布更为均匀的乳液体系.  相似文献   

19.
由沉淀法和溶胶-凝胶法分别制备了Ni Fe_2O_4和Ti O_2,并用XRD和SEM对两种粒子进行了表征,结果表明成功制备了粒径大小较为均匀的目标产物。用CTAB对Ni Fe_2O_4进行了改性,并由IR和Zeta电位测试予以确认。以改性Ni Fe_2O_4和Ti O_2作为稳定粒子,由两步法制备了W/O/W型多重Pickering乳液,采用数码照片和光学显微照片观察所制备的乳液的宏观与微观形貌。研究表明,制备的单重Pickering乳液粒径较为均匀,多重Pickering乳液粒径范围稍宽,但两者稳定性能都非常良好。  相似文献   

20.
Delayed crosslinking polymer gel systems are widely used in-depth profile control technology for water production control. In this paper, an amphiphilic polymer P(AM-NaA-DDAM) was synthesized by a free radical micellar polymerization method and a delayed crosslinking amphiphilic polymer gel system was prepared based on multiple emulsion of W1/O/W2 emulsion which was prepared by a two-step emulsification method. The optimized formulation of amphiphilic polymer gel systems is: 0.15% P(AM-NaA-DDAM), 0.3% methenamine, 0.02% resorcinol, and 0.3% citric acid. The delayed gelation time of the delayed crosslinking amphiphilic polymer gel system is closely related to the stability of the W1/O emulsion. By using multiple emulsion delayed crosslinking method, the delayed crosslinking amphiphilic polymer gel system with diesel as the oil phase can delay the gelation time up to 168 hours.  相似文献   

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