Effect of Drying Process Parameters on Dehydrated Cabbage Enriched with Selenium

Cabbage (Brassica oleracea var. capitata L.) enriched with selenium through foliar spraying was used to study the effect of drying process on its selenium retention and other quality criteria. Parameters such as blanching, seasoning, temperature, pH, and time of treatment were studied and evaluated to obtain an optimal processing condition for dehydrated selenium-enriched cabbage. After blanching, the barrier for mass and heat transfer of cabbage cellular materials became lower so that the heat damage was high. Blanching parameters set at 95°C and 60 s retained selenium and vitamin C in cabbage best as well as inactivated enzymes present in cabbage. Seasoning reduced the water activity of cabbage and subsequently reduced the loss of selenium. Blanching and seasoning could prevent browning deterioration of cabbage and reasonably kept the fresh color. The selenium loss kinetics during drying obeyed the first-order reaction and its activation energy was 44.0 kJ mol^-1.     

Determination of selenium in garlic (Allium sativum) and onion (Allium cepa) by electro thermal atomic absorption spectrometry

A separation/enrichment procedure has been developed for the determination of selenium in garlic and onion samples by electrothermal atomic absorption spectrometry (ET-AAS) as a slurry sampling after preconcentration with 3,3-diaminobenzidine (DAB) reagent on the activated carbon. The influences of pH, time, amount of carbon and complexing reagent were outlined. The effect of acids used in the digestion of samples was also studied and compared. Selenium level was found to be 0.024 μg g⁻¹ for onion (n = 5; LOD – 0.5 μg L⁻¹; LOQ – 1.7 μg L⁻¹) and 0.015 μg g⁻¹ for garlic (n = 5; LOD – 1.3 μg L⁻¹; LOQ – 3.3 μg L⁻¹). Three different samples of garlic were analyzed by k₀-instrumental neutron activation analysis (k₀-INAA) at the Jozef Stefan Institute (JSI). The data obtained by k₀-INAA show that the content of selenium overlapped the results obtained by ET-AAS.     

Geographical,seasonal and formula-specific variations in the selenium levels of infant formulae

Fortification of infant formulae with selenium (Se) is currently under consideration by manufacturers and regulatory bodies. However, information on the endogenous Se levels of infant formulae is largely lacking. The objective of this study was to describe the seasonal-, geographic- and formula-specific variations in endogenous Se levels of infant formulae.     

真空蒸馏脱硒的研究

本文从理论上分析了真空蒸馏脱Se的影响因素时间和温度,并通过实验给予验证,提出了最佳条件,对工业采用真空蒸馏脱出含Se物料中的Se具有一定的指导性。     

Synthesis of selenium nanoparticles in the presence of silk fibroin

This paper describes a solution-phase approach to the synthesis of selenium nanoparticles by reducing selenious acid solution with ascorbic acid in the presence of silk fibroin. The monodispersed spherical selenium colloid particles obtained were very stable in silk fibroin solution and characterized by Atomic force microscopy and X-ray techniques. The influences of temperature and ultrasonication on the morphology of selenium nanoparticles were also discussed. The experiments showed that the selenium nanoparticles with various morphologies could be obtained under different temperatures and the appropriate ultrasonication time was 60 min. This result indicated that the silk fibroin molecules intimately associated with the surface of the selenium particles and controlled the growth particles.     

Diffraction efficiency change in PVA/AA photopolymer films by photosensitive inorganic compound addition

The highest diffraction efficiency (DE) value after illumination and post-curing of photopolymer films were obtained at the SeO₂/Acrylamide (AA) Ratios of AA 3.0 g, SeO₂ 1.0 g and the DE’s were stable values of over 90%. By the addition of SeO₂, the maximum DE at the initial stage of illumination was reached at 300 seconds, which suggests SeO2 slows down the photopolymerization of. DE variation curve for the optimum composition during extendedtime illumination of 9,000 seconds resembles a sine curve due to the combination of the monomer diffusion and the photopolymerization, and the photopolymer film expanded at about 8% after photopolymerization due to monomer migration.     

增效剂对油溶性茶多酚硒的抗氧化增效作用研究

在100℃恒温及黑暗条件下,采用空气自然氧化考察了维生素C、酒石酸、柠檬酸对LTP-Se在蓖麻油中抗氧化性能。结果表明m(增放剂)的添加量为0.01%、0.03%、0.05%时,对油溶性茶多酚硒抗氧化增效效果较好,m(VC)添加量为0.05%,LTP-Se添加浓度为100mg/kg的油样抗氧化生最佳。     

硒作为油脂抗氧化剂的功用探讨

硒作为人体的一种必需微量元素，其生化功能是多方面的。而其中最重要的是硒的抗氧化性，是在七十年代才引起人们的注意，本文就硒在油脂中的抗氧化机理、硒作为油脂抗氧化剂的功用、硒在油脂领域的开发与应用作一探讨。     

氢化物原子荧光法直接测定地质样品中痕量硒和碲

研究了采用氢化物原子荧光法同时对硒、碲进行直接测定的条件，拟定了适合于一般地质样品中痕量硒和碲的分析方法。     

Simultaneous photoreductive removal of copper (II) and selenium (IV) under visible light over spherical binary oxide photocatalyst

Waste water of copper mines and copper processing plant contains both copper and selenium ions with other contaminants. In this paper simultaneous photoreductive removal of copper (II) and selenium (IV) is studied for the first time using spherical binary oxide photocatalysts under visible light. All the synthesized materials are found to be mesoporous in nature with reasonably high surface area. Among a range of hole scavengers, only EDTA (ethylene diamine tetraacetic acid) and formic acid are found to be the most active for the reduction reaction. A comparative study is carried out using both the hole scavengers varying reaction time, concentration, pH etc. For a single contaminant, EDTA is found to be the best for Cu(II) reduction whereas formic acid is the best for Se(IV) reduction. In a mixed solution both EDTA and formic acid perform very well under visible light irradiation. Highest photocatalytic reduction in a mixed solution is observed at pH 3. Among all the synthesized materials, TiZr-10 performs as the best photocatalyst for both Cu(II) and Se(IV) reduction. However under UV light, Degussa P25 performs slightly better than TiZr-10. Present study shows that 100 ppm of mixed solution can be removed under visible light in 40 min of reaction using TiZr-10 as catalyst. Photodeposited material is found to be copper selenide rather than pure copper and selenium metal. This indicates that the waste water containing copper and selenium ions can be efficiently treated under visible or solar light.