999 resultados para FTICR-MS


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A method was developed for the determination of lanthanum in the cytoplasm of human erythrocytes after they were incubated in lanthanum nitrate or citrate solutions. The lanthanum concentration in the cytoplasm of incubated erythrocytes is much higher than that in normal erythrocytes. It is suggested lanthanum can transport through the membrane of erythrocyte in vitro. Solutions containing chelator are unsuitable to be washing buffer in the investigation.

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应用基质辅助激光解吸电离飞行时间质谱 ( MALDI- TOF- MS)技术对系列环状预聚体进行了表征 ,分别确定了系列环状预聚体各自不同的聚合度 ,同时对它们的结构进行了确认 ,获得了满意的结果。实验结果表明 MALDI- TOF- MS是分析环状预聚体准确、快速工具之一

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用气相色谱(GC)与气相色谱—质谱(GC-MS)联用技术对哈士蟆油中的脂肪酸组成进行了定性与定量分析,共鉴定出10种脂肪酸并用气相色谱法作了定量,对所得的结果进行了讨论。

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目的: 分析测定长白山白眉蝮蛇蛇毒纤溶酶和磷脂酶A2 的分子量和纯度。方法与结果: 应用MALDI/TOF MS法测定纤溶酶的分子量为23333±90,磷脂酶A2的分子量为14000±20,相对偏差在0138%以内。结论: 应用此方法未检测到杂蛋白质谱峰的存在, 酶的纯度较好, 测得结果要比电泳法准确。MALDI/TOF MS提供了一种测定蛋白质药物纯度快速准确的新方法。

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采用MALDI TOF MS法快速测定了天花粉蛋白的分子量,并讨论和对比了三种不同基质对其影响,认为用基质芥子酸是最佳适宜条件。实验结果表明本方法优于其它传统的测定生物大分子分子量方法

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利用MALDI-TOF-MS法测定了谷胱甘肽S-转移酶的分子量,并讨论和对比了三种不同基质对其影响,认为用α-氰基-4-羟基肉桂酸(α-CHC)作基质是最佳适宜条件。实验结果表明本方法优于其它传统的测定生物大分子分子量方法。

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The electron impact mass spectrum (EIMS) of 3-phenyl-1-butyn-3-ol was reported in this paper. Collision-induced dissociation (CID) was used to study the gas phase ion structure of [C8H7](+) formed by the fragmentation of ionized 3-phenyl-1-butyn-3-ol, and that it has the same structure as m/z 103 ions generated by cinnamic acid and alpha-methylstyrene. Deuterium labelling, metastable ion (MI) and CID experimental results indicate the formation of m/z 103 ion resulting from molecular ion of 3-phenyl-1-butyn-3-ol, which is a stepwise procedure via twice proton transfers, rather than concerted process during the successive elimination of methyl radical and neutral carbon monoxide accompanying hydrogen transfer. Moreover, in order to rationalized these fragmentation processes, the bimolecular proton bound complex between benzyne and acetylene intermediate has been proposed.

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The fragmentations of the product ions produced by the ion-molecule reaction of the halogeno-benzene (chlorobenzene, bromobenzene and iodobenzene) were studied using the collision-induced dissociation, The main product ions of the ion-molecule reaction of three kinds of halogeno-beneze include the dimeric ions, m/z(2M-X) ions and m/z(2M-2X) ions, The CID spectra of these ions were compared with that of the protonated bromodiphenyl and biphenyl, The formation mechanism and the structure of the product ions were obtained.

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通过糖类化合物3种常用基质MALDI-MS分析效果的比较以及寡糖和多糖正、负离子MALDI-MS谱的对比,找到了适合糖分析的基质2,5-DHB,探讨了糖类化合物激光解吸/电离条件下形成离子的过程,指出了Na+、K+离子在寡糖分子量测定中的重要作用,借助柱层析分离手段,成功地测出了分子量大于10000的葡聚糖的分子量.

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用基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)技术研究了F-46和JF-43型酚醛环氧树脂。获得了该类树脂的聚合度及其不同聚合度组分的分子结构;发现该类树脂中含有环氧氯丙烷的聚合物,给出了可能的分子结构。

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应用基质辅助激光解吸电离飞行时间质谱(MALDI-TOF-MS)技术,研究了E-12、E-31、E-42、E-44和E-51五种牌号环氧树脂。获得了该类树脂的聚合度及其不同聚合度所对应的分子结构;发现了该类树脂中有一定量的环氧氯丙烷的聚合物,并给出了可能的分子结构。

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本文报道了7种新合成的(Z)-1-[2-(三芳基锡)乙烯基]-1-环庚醇有机锡化合物的XPS和MS结果。通过XPS讨论了化合物中不同取代基的存在,对锡内层电子的影响及取代基对Ols结合能化学位移的作用。结果表明,卤素在这里起着重要的作用。通过MS和XPS讨论了不同取代基对O→Sn键的影响。

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采用气相色谱/质谱(GC/MS)联用技术对山东泰山产单叶蔓荆子挥发油的化学成分进行了分析,分离出30多个峰,确认了其中28种成分,占总离子流的95%以上,并对挥发油的主要化学成分Δ3-蒈烯,用气相色谱/傅里叶红外光谱(GC/FTIR)法进行了验证。

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采用对掺入La_2O_3的石墨棒原位活化并结合交换电极回放方法制备了产率较高的金属富勒烯,并用甲苯高温热提取的方法有效地提取出La@C_(2n),其中La@C_(74)为可溶性金属富勒烯增加了新成员.同时,首次采用解吸电子轰击质谱对提取物进行了表征,讨论了提取物的ESR谱.