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91.
92.
93.
为确定以不同硒含量的大豆为原料生产豆腐过程中硒分布特性,用石墨炉原子吸收分光光度法对该过程中各种产物的硒含量进行了分析研究。结果表明,以硒含量分别为0.692、2.561、2.801 mg/kg的大豆为原料生产得到的豆腐、黄浆水、豆渣的硒含量分别为:0.089、0.250、0.138 mg/kg,0.462、0.760、0.507 mg/kg和0.532、0.764、0.524 mg/kg。豆腐生产过程中,以低硒大豆为原料生产豆腐,硒总回收率为75.59%;采用富硒大豆为原料生产,硒的回收率分别达到87.37%、87.20%;生产过程中豆腐、黄浆水和豆渣中硒含量占总回收硒的比率分别为39.01%~49.97%、23.92%~29.89%、26.11%~30.92%。 相似文献
94.
Reinoso S Vitoria P Gutiérrez-Zorrilla JM Lezama L San Felices L Beitia JI 《Inorganic chemistry》2005,44(26):9731-9742
Reaction of in situ generated copper(II)-monosubstituted Keggin polyoxometalates and copper(II)-bipyridine-oxalate complexes in the corresponding alkaline acetate buffer led to the formation of hybrid metal organic-inorganic compounds K(2)[{SiW(11)O(39)Cu(H(2)O)}{Cu(2)(bpy)(2)(H(2)O)(2)(mu-ox)}(2)].14H(2)O (1), K(14)[{SiW(11)O(39)Cu(H(2)O)}{Cu(2)(bpy)(2)(mu-ox)}](2)[SiW(11)O(39)Cu(H(2)O)].55H(2)O (2), (NH(4))(4)[{SiW(11)O(39)Cu(H(2)O)}{Cu(2)(bpy)(2)(mu-ox)}].10H(2)O (3), and Rb(4)[{SiW(11)O(39)Cu(H(2)O)}{Cu(2)(bpy)(2)(mu-ox)}].10H(2)O (4). Their structures have been established by single-crystal X-ray diffraction. The main structural feature of these compounds is the presence of copper(II)-monosubstituted alpha-Keggin polyoxoanions as inorganic building blocks, on which the mu-oxalatodicopper metalorganic blocks are supported. Compound 1contains the discrete hybrid polyanion [{SiW(11)O(39)Cu(H(2)O)}{Cu(2)(bpy)(2)(H(2)O)(2)(mu-ox)}(2)](2)(-), whereas the polymeric hybrid polyanion [{SiW(11)O(39)Cu(H(2)O)}{Cu(2)(bpy)(2)(mu-ox)}(2)](n)(4)(n)(-) gives a monodimensional character to compounds 2-4. Magnetic and EPR results are discussed with respect to the crystal structure of the compounds. DFT calculations on both the [Cu(2)(bpy)(2)(H(2)O)(4)(mu-ox)](2+) cationic complex and the metalorganic blocks have been performed in order to determine the optimized geometry and the magnetic coupling constants, respectively. 相似文献
95.
Let G be a non-compact connected semisimple Lie group with finite center and let GK denote the centralizer of a maximal compact subgroup K of G inG, the universal enveloping algebra over of the Lie algebra of G. In [4] Lepowsky defines an injective anti-homo morphism P:G
KK
MA, where M is the centralizer in K of a Cartan subalgebraa of the symmetric pair (G,K),K andA are the universal enveloping algebras over corresponding to K anda, respectively, andK
M is the centralizer of M inK. The subalgebra P(G
K) ofK
MA has considerable significance in the infinite dimensional representation theory of G. In this paper we explicitly compute P(G
K) when G=S0o(4,1), and show how this result leads to the determination of all irreducible representations of G and its universal covering group Spin(4,1).Partially supported by CONICET (Argentina) grants. 相似文献
96.
硒素营养对麦芽质量指标的影响 总被引:1,自引:0,他引:1
大麦在制麦过程中的溶解对麦芽质量、啤酒的酿造以及成品啤酒的质量有重要的影响。本文利用生物转化技术,以微量元素硒作为制麦添加剂,以提高麦芽质量。本实验中,浸麦采用第一次浸6h以下采用浸二断四的工艺,浸水时每小时换水一次,一直通风,当浸麦度达40%~42%时,用硒溶液处理1h。发芽前两天每天补水两次,后期促进其凋萎。焙燥过程中前期低温大风量排湿,中期合理稳步升温,后期严格控制焙焦温度,使整个过程稳定。测定制得的成品麦芽的糖化力、α-AN、无水浸出率、色度等质量指标。发现硒对麦芽的质量有一定的影响。 相似文献
97.
Serrano MC Portolés MT Vallet-Regí M Izquierdo I Galletti L Comas JV Pagani R 《Macromolecular bioscience》2005,5(5):415-423
Tissue engineering offers the potential of providing vessels that can be used to replace diseased and damaged native blood vessels. The endothelization of a synthetic vascular graft minimizes the failures associated with blood clotting and platelet activation. The aim of this study was to culture vascular-derived endothelial and smooth muscle cells on both untreated and NaOH-treated poly(epsilon-caprolactone) (PCL) films, a biocompatible and bio-resorbable polymer, and to evaluate the behavior of both cell types as a preliminary study for vascular graft development. PCL films were prepared by hot pressing; characterized by DSC, IR, SEM, and scanning force microscopy; and treated with NaOH to increase the surface hydrophilicity before cell culture. Endothelial and smooth muscle cells, isolated from pig cava vein, were characterized by immunofluorescence and confocal microscopy studies of endothelial nitric oxide synthase and alpha-smooth muscle actin. Good adhesion, growth, viability and morphology of both the endothelial and smooth muscle cells on PCL films were obtained, but a light stimulation of mitochondrial activity was observed during short culture times. NaOH treatment improved the adhesion and enhanced the proliferation in both cell types. This verified the possible use of this modified polymer as a support in the preparation of a synthetic vascular graft. [Diagram: see text] SEM micrograph of smooth muscle cells cultured on NaOH-treated PCL film. (Original magnification: 1000x). 相似文献
98.
Jaime L. Matta Juan M. Ramos Roy A. Armstrong Hector D'Antoni 《Photochemistry and photobiology》2005,81(3):563-568
Apoptosis involves a highly organized and programmed series of events aimed at maintaining genomic stability by eliminating defective host cells. The purpose of this study was to determine the threshold doses and environmental UV‐A and UV‐B exposure times necessary to produce apoptosis and necrosis in the normal cells of a human fibroblast cell line. Enviromental UV‐A and UV‐B doses were measured over a 6 year period with a four‐channel UV radiometer. The fibroblasts were irradiated once using an Oriel UV Solar Simulator with six doses of environmentally‐based UV. Doses corresponded to 0,11,19,23 and 45 min of average environmental UV‐A and UV‐B radiation at solar noon in Puerto Rico. The Annexin‐V binding method was used to differentiate between normal fibroblasts and apoptotic or necrotic fibroblasts. The threshold dose from apoptosis to necrosis was found between 24–28 kJ/m2, which corresponded to 19 and 23 min of environmental UV‐A and UV‐B exposure. This study provides the first data that specify the environmental threshold doses of UV‐A and UV‐B at which human fibroblasts undergo apoptosis and necrosis. These results may provide valuable dose‐response thresholds for apoptosis and necrosis for future mechanistic studies and baseline data for skin cancer prevention programs. 相似文献
99.
ZHOU Cheng-He Juan F.Miravet M.Isabel Burguete Santiago V.Luis BAI Xue YUAN Yong 《有机化学》2004,24(Z1):380
Polynitrogen receptors such as bis-histidine peptides possess strong ability to bind metals, which play much important roles in medicinal, bioinorganic, bioorganic, biomimetic and supramolecular chemistry. In order to investigate the interaction of these hosts with a variety of neutral, cationic and anionic guests, several techniques, for example, NMR,potentiometric tirations and monocrystal X-ray diffraction have been employed. Among them NMR is a powerful technique for unraveling the structure of polynitrogen receptors as long as they are in solution where the rapid tumbling of molecules averages out the anisotropies such as chemical shift and dipole-dipole interactions. General 1H NMR approach has been widely used for the study of host-guest interaction, but it is difficult for the accurate measurement in complexes structures, particularly metal complexes structures in which how the polynitrogen receptors bind metal, and which nitrogen binds metal and so on. 相似文献
100.