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流动注射化学发光抑制法测定维生素E   总被引:4,自引:0,他引:4  
实验发现,H2SO4-KMnO4-甲醛在丙酮存在下发光信号大大增强,据此建立了H2SO4-KMnO4-甲醛-丙酮新体系。同时发现维生素E(VE)对H2SO4-KMnO4-甲醛-丙酮化学发光体系有强烈的抑制作用,建立了维生素E的流动注射化学发光抑制法的新体系。化学发光信号的降低值与VE的浓度在1.0×10-5~1.0×10-3mol/L的范围内呈良好的线性关系,方法的检出限为3.0×10-6mol/L。对1.0×10-4mol/L的VE进行11次平行测定,其相对标准偏差为1.5%。该法已用于VE片剂中VE的测定。  相似文献   
2.
采用高效液相色谱法测定了辅酶Q10(CoQ10)的含量,并探讨了CoQ10的防晒性能.色谱柱为Kromasil 5-C18柱(150×4.6 mm,5μm);流动相为甲醇-无水乙醇(体积比30:70),流速为1.0 mL/min;检测波长275 nm.实验考察了不同含量CoQ10在3个紫外区的防晒性能,及与维生素C或维...  相似文献   
3.
基于灰色关联的虚拟企业伙伴选择   总被引:2,自引:0,他引:2  
虚拟企业组建时,面对网络上众多且又处于分散无序状态的潜在合作资源,往往难以找到合适的合作伙伴.研究了虚拟企业选择伙伴的指标体系,应用层次分析法计算出各指标的权重,并借鉴灰色关联度理论较好地解决虚拟企业网络化资源伙伴的选择问题.  相似文献   
4.
The density and viscosity of propane mixed with 66/34 trans/cis-decahydronaphthalene were measured over a wide range of temperatures (323-423 K), pressures (2.5-208 bar), and compositions (0-65 mol% propane). For conditions giving two phases, the composition of the dense phase was measured in addition to the density and viscosity. The modified Sanchez-Lacombe Equation of State (MSLEOS) was used with a single linearly temperature-dependent pseudo-binary interaction parameter to correlate the phase compositions and densities. The compositions and densities of the mixtures were captured well with absolute average deviations between the model and the data of 5.3% and 2.3%, respectively. The mixture viscosities were computed from a free volume model (FVM) by using a single constant binary interaction parameter. Density predictions from the MSLEOS were used as input mixture density values required for the FVM. The FVM was found to correlate well with the mixture viscosity data with an absolute average deviation between the model and the data of 5.7%.  相似文献   
5.
工程项目招标评标应当遵循公平、公开、公正、科学、择优的原则,基于熵值法,运用价值工程(VE),提出了一个对工程投标人的商务标、技术标进行定量评价的分析模型,并从实例的角度,以验证其可行性和可操作性。  相似文献   
6.
Novel unsaturated poly(ester-amide)s (UPEAs) were prepared by the reaction of Bisphenol-F based epoxy resin with bisamic acids. Acrylation of UPEAs were carried out using acryloyl chloride and the products are called Acrylated unsaturated poly(ester-amide)s (AUPEAs). These UPEAs were then treated with acrylol chloride to afford acrylated UPEAs resin (i.e., AUPEAs). Interacting blends of equal proportional AUPEAs and vinyl ester epoxy (VE) resin were prepared. APEAs and AUPEAs were characterized by elemental analysis, molecular weight determined by vapor pressure osmometer, IR spectral study and thermogravimetry. Curing of interacting blends was monitored on differential scanning calorimeter (DSC). Based on DSC data ‘in situ’ glass reinforced composites of the resultant blends have been prepared and characterized for mechanical, electrical and chemical properties. Unreinforced blends were characterized by thermogravimetry (TGA).  相似文献   
7.
虚拟企业是个开放性的复杂系统,其本质是协调成员企业的管理,提高和协调其有序性以达到协调增值的目的.基于现金流,通过黑箱理论与投入产出模型分别建立了成员企业、虚拟企业以及信息共享下的虚拟企业价值评估模型,通过比较三者的差值评估虚拟企业的协同增值效应.  相似文献   
8.
Unsaturated bisamic acids were prepared by reaction between maleic anhydride and different aromatic diamines. Unsaturated poly(ester-amide) resin (UPEAs) was prepared by reaction of diglycidylether of bisphenol-A (DGEBA) with unsaturated bisamic acids. Acrylation of Unsaturated poly(ester-amide)s (UPEAs) was carried out to afford acrylated UPEAs resin (i.e., AUPEAs). Interacting blends of Acrylated unsaturated poly(ester-amide)s (AUPEAs) with vinyl ester epoxy (VE) resin were prepared. APEAs and AUPEAs were characterized by elemental analysis, molecular weight determined by vapor pressure osmometer and by IR spectral study and by thermogravimetry. The curing of interacting blends was monitored on differential scanning calorimeter (DSC). Based on DSC data in situ glass reinforced composites of the resultant blends have been prepared and characterized for mechanical, electrical and chemical properties. Unreinforced blends were characterized thermo-gravimetrically (TGA).  相似文献   
9.
紫外光谱法对维生素E油酸酯、维生素E与油酸的同时测定   总被引:1,自引:0,他引:1  
建立了混合体系中维生素E、油酸和维生素E油酸酯同时测定的方法,用光纤光谱仪获取混合体系紫外-可见透射光谱.实验按均匀设计建立校正集和预测集,在255 ~315 nm波段采用偏最小二乘法建立了同时定量测定该3组分的校正模型,并用间隔区间偏最小二乘法(iPLS)通过优选建模区间改进油酸的预测模型.采用iPLS能够显著提高模型准确度,尤其对光谱弱响应的物质,最大相对误差从PLS直接建模的54.7%降至iPLS的8.98%,建立的模型可满足动力学研究的原位分析需要.  相似文献   
10.
郑熠斌  黄百芬  任一平 《色谱》2016,34(7):692-696
建立了正相高效液相色谱测定食物中8种维生素E异构体及维生素A的方法。样品中的维生素E异构体和维生素A经皂化和液液萃取,Waters ACQUITYTM UPLC BEH Amide色谱柱(150 mm×3.0 mm, 1.7 μm)分离,体积比为90 : 10的正己烷与叔丁基甲基醚-四氢呋喃-甲醇(20:10:1, v/v/v)为流动相,荧光检测器和紫外检测器串联检测。4种生育酚在5.0~60.0 mg/L(r2≥0.9999)、维生素A和4种三烯生育酚在0.5~6.0 mg/L(r2≥0.9996)范围内具有良好的线性,各基质中目标物的检出限在20~60 μg/kg之间;9个组分在各基质中的加标回收率为79.2%~114.2%,相对标准偏差(RSD)为1%~12%。该方法简便、灵敏、可靠、环保,可用于食物中8种维生素E异构体以及维生素A含量的同时测定。  相似文献   
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