共查询到20条相似文献,搜索用时 79 毫秒
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采用GC法和HPLC法对北豆根多糖的单糖组成进行分析比较。采用糖腈乙酸酯衍生化—GC法和1-苯基-3-甲基-5-吡唑啉酮(PMP)柱前衍生—HPLC法分别对北豆根多糖的单糖组成进行测定,并评价两种方法的适用性。GC法检测出D-鼠李糖(D-Rha)、D-阿拉伯糖(D-Ara)、D-木糖(D-Xyl)、D-甘露糖(D-Man)、D-葡萄糖(D-Glc)和D-半乳糖(D-Gal);HPLC法检测出D-甘露糖(D-Man)、D-鼠李糖(D-Rha)、D-葡萄糖(D-Glc)、D-阿拉伯糖(D-Ara)、D-半乳糖(D-Gal)、D-木糖(D-Xyl),其中D-阿拉伯糖(D-Ara)和D-半乳糖(D-Gal)的色谱峰重叠。两种方法均检测出6种中性糖组分,对比北豆根多糖的单糖组成分析GC法和HPLC法联用较为适合。 相似文献
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气相色谱中多种死时间测定方法的比较 总被引:1,自引:0,他引:1
由烷烃同系物的保留时间计算死时间的方法有多种,常用的并得到认可的有Grobler-Balizs法(G-B法)、Guaradino法(G法)、Peterson-Hirsch法(P.H法)和Ambms法(A法)等。文献[5]已证明A法和G-B法是同一的。本文是文献[5]的继续,将证明A法、P-H法和G法也是同一的。 相似文献
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运用循环伏安法(CV)、计时电流法(CA)、计时库仑法(CC)、方波伏安法(SWV)研究了卡马西平(CBZ)在纳米二氧化钛(nano-TiO2)与离子液体1-苄基-3-甲基咪唑六氟磷酸盐([BnMIM]PF6)复合修饰碳糊电极(nano-TiO2-[BnMIM] PF6/CPE )上的电化学行为、电化学动力学性质及电分... 相似文献
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综述了近年来我国水中氯化物检测及样品前处理技术的研究进展。样品前处理技术包括试剂法和离子交换树脂法;检测方法包括常规化学分析法(容量法和分光光度法)、电分析方法(电位滴定法和电化学法)、离子色谱法、光谱法(原子吸收光谱法和共振光散射光谱法)、连续流动注射法等(引用文献37篇)。 相似文献
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对测定食品中微量元素硒的前处理方法(干法、湿法、微波消解法等)和检测方法(原子光谱法、分子光谱法、色谱法、电化学法等)的现状(主要在1990~2010年间发表的文献)及相关的原理和方法的特点之处作了综述(引用文献20篇)。 相似文献
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目次Ⅰ、绪言Ⅱ、矿石的光谱定量分析法(一)固体分析法(1)粉末法i)冲淡法;ii)增量法;iii)结合化学处理法;iV)可利用的几种技术(空气冷却电极,转动或移动电极)。(2)压片法(二)液体分析法(1)液面打弧法;(2)干燥后打弧激发;(3)喷入光源法;(4)在液体中放电;(5)溶液流入法;(6)熔化后打弧。(三)气体分析法(1)利用带光谱;(2)用低压火花光源。(四)几种有用的技术(1)减除氰带光谱的方法;(2)阴极层效应的利用;(3)特殊形状电极的利用(双电弧、双室电极、物理 相似文献
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综述了农产品中重金属的检测方法如光谱分析法(包括原子吸收光谱法、电感耦合等离子体原子发射光谱法、原子荧光光谱法和X射线荧光光谱法)、色谱分析法、电化学分析法和快速检测方法(包括酶联免疫吸附法、生物传感器法、酶抑制法、试纸和试剂比色法)的研究进展,并对其发展前景进行了展望(引用文献83篇)。 相似文献
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研究了一类以苯氧基作疏水支链的新型阴离子表面活性剂——N-(α-烷苯氧基)十四酰基牛磺酸钠(SAPTT)水溶液的紫外吸收光谱、探针(芘)稳态荧光发射光谱及自身稳态荧光发射光谱性质.研究结果表明,荧光探针(芘)法和自身稳态荧光法可用来测定这类表面活性剂的临界胶束浓度(CMC),且测定结果与表面张力法(吊片法)接近;与荧光探针(芘)法相比,对于所研究体系,自身稳态荧光法的灵敏度和准确性均较高,所测得CMC结果与表面张力法(吊片法)能较好地吻合. 相似文献
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The spectral-polarization characteristics of absorption and phosphorescence of molecules of the initial form of nitro-substituted
indolinospirobenzothiopyran were studied in oriented polyethylene films and in solutions with different polarity. An oscillator
model of the electron transitions responsible for the formation of absorption and luminescence spectra was suggested. It was
established that the principal differences in the spectral and photophysical properties of the compound studied and its oxygen-containing
analog are associated with the fact that the electronegativity of the S atom is lower than that of the O atom.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 6, pp. 1143–1146, June, 1997. 相似文献
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Cotton cellulose was swollen in a sodium hydroxide solution and carboxymethylated by a two-bath method for different periods of time for each process. The kinetics of acid hydrolysis and the crystallinity of the swollen and carboxymethylated samples were measured. The proportion of broken bonds, rate constants for hydrolysis, and permeability of cellulose to hydrolyzing agents were calculated. The susceptibility of glycosidic linkages to acid hydrolysis was improved by carboxymethylation more than by swelling in alkali. The increased accessibility of carboxymethylcellulose to acid was regarded as a consequence of increased intra-and intercrystalline swelling and of the glycosidic bonds' weakness caused by the electron-attracting carboxymethyl group on the C-6 position. 相似文献
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The aim of the presented work was the investigation of thermal oxidation of ilmenite in static air atmosphere. The investigations
were carried out by use of a derivatograph (MOM, Hungary). The changes of crystallographic structure of investigated samples
were identified by X-ray diffractometry on Philips PW-1710 diffractometer. In temperature above 500°C appears structure of
hematite Fe2O3. On the basis of the thermogravimetric measurements, the contracting area and contracting volume models were found as the
best fitting experimental data.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
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Cyclopropyl derivative of 2,6-di-tert-butylphenol is synthesized as a probe to investigate the mechanism of base-catalyzed autooxidation of phenol derivatives. Our study indicates that one electron reduction of molecular oxygen from phenolate gives phenoxyl radical 3, a key intermediate of autooxidation. The coupling of phenoxyl radical and superoxide radical gives peroxylate anion 4 and produces the final epoxy alcohol adduct 6. 相似文献
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微量钙的测定方法研究进展 总被引:5,自引:0,他引:5
介绍了1995-2006年期间测定微量和痕量钙的方法,如电感耦合等离子体-原子发射光谱法、原子吸收光谱法以及离子色谱法等的工作原理和特点,并说明了其测定微量钙的应用领域。并对微量钙的测定技术进行了展望(引用文献55篇)。 相似文献
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Thermal behaviour of sodium oxo-salts of sulphur: Na2SO4, Na2S2O7, Na2S2O6, Na2SO3, Na2S2O5, Na2S2O4, Na2S2O3, Na2S3O6 and of sulphides Na2S and Na2S2 was studied on heating up to 1000°C. The experiments were performed with anhydrous compounds obtained from commercial products
by recrystallisation and dehydration. The stage mechanisms of decomposition of anionic sub-lattices of the salts have been
proposed basing on the Górski’s morphological classification of simple species. The thermal stability and the stage decomposition
mechanisms were correlated with the structure and the potential chemical properties of the salt anions. The thermal decomposition
processes were studied by means of thermal analysis, and the decomposition products were identified by means of X-ray phase
analysis. 相似文献