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60 hz低频电磁场对α-淀粉酶催化效率的影响及作用机理

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食品工业科技 2019年第11期40卷 50-56页

作者：杨慧林日辉樊艳叶廖安平蔡杏华韦世昌廖成超广西民族大学化学化工学院广西多糖材料与改性重点实验室培育基地广西高校化学与生物转化过程新技术重点实验室广西南宁530006 广西民族大学海洋与生物技术学院广西高校微生物与植物资源利用重点实验室广西南宁530006 广西民族大学相思湖学院广西南宁530006

为了研究低频电磁场对酶促反应的影响及其作用机理,本文以α-淀粉酶催化水解玉米淀粉为酶促反应模型,使用60 hz低频电磁场(LF-EMF)进行持续辐射处理,通过分析低频电磁场辐射对酶促淀粉水解反应效率的影响,以及低频电磁场辐射对底物结构... 详细信息

为了研究低频电磁场对酶促反应的影响及其作用机理,本文以α-淀粉酶催化水解玉米淀粉为酶促反应模型,使用60 hz低频电磁场(LF-EMF)进行持续辐射处理,通过分析低频电磁场辐射对酶促淀粉水解反应效率的影响,以及低频电磁场辐射对底物结构、酶结构、及溶液体系传质等方面的影响,初步探讨了低频电磁场对酶促反应影响的作用机理。结果表明:低频电磁场可促进α-淀粉酶催化的淀粉水解反应,反应10 h时,产水解糖达14.39 mg/mL,比对照实验(12.41 mg/mL)提高了15.90%(p0.05);未发现低频电磁场引起α-淀粉酶一级结构的明显变化,也未发现低频电磁场辐射导致酶的二级结构/三级结构不可逆的改变(p>0.05);低频电磁场可降低α-淀粉酶催化反应体系的最适离子强度(0.0947 mol/L),并降低高离子强度对酶促反应的抑制作用;氯化钠的扩散实验表明低频电磁场可促进溶液体系的传质,其中,离子扩散的增强因子为1.23,表观膜厚度由1.26 cm减少到1.08 cm,降低了14.29%(p<0.05)。LF-EMF辐射提高了α-淀粉酶催化玉米淀粉水解的反应效率,原因之一是强化了反应传质,但不排除其影响α-淀粉酶的构象进而提高酶活性的可能性。

关键词：低频电磁场 α-淀粉酶酶促反应作用机理

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陶瓷物理及化学原理修订第5版修订第五版

6 - 28 Status Report of On-line Ion Sources in 2013

1975年

作者：（德）h.舒尔兹编黄照柏译

来源：汇雅图书（南通市图书馆... 评论

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IMP & hIRFL Annual Report 2013年第1期 259-260页

作者： Feng Yucheng Lu Wang ZhangWenhui Ma hongyi Ma Baohua Wang hui Li Jiaqing Lin shuhao Cao Yun sh-a shan Wu Qi Guo Junwei Fang Xing Yang Yao Qian Cheng Zhang-J unjie Li Xixia Zhang hengjuan Zhao huanyu Zhang Xuezhen Sun Liangting Zhao hongwei

Study on the Reaction Behavior of Some Trinuclear Complexes of Transition Metals: [Fe_2M(μ_3-O) (μ-O_2CCh_3)_6(h_2O)_3]·xh_2O by the Method of Probe Reaction of Acetic Acid

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Chinese Journal of Structural Chemistry 1998年第5期17卷 365-371页

作者： hE Ling-Jie ChEN Bo CAI Su-hua WANG Yan-Ming ZhOU Wen-Bo ZhANG Lin-Na (Fujnin Institute of Research on the Structure of Matter,the Chinese Academy of Sciences, Fuzhou, Fujian 350002, China)XIE Qing-shan (Present address:shishi Organizing Committee ,sh 中科院福建物质结构所福建福州

The reaction behaviors of the title complexes have been studied in the system of dinitrogen gas by means of in situ IR. It has been found that some active fragments created at some stage of the thermal decomposition process of the complexes enable the acetic acid both obtained from the ligand of the complexes and introduced from outside to convert to acetone by decarboxylation. Their optimum reaction temperatures are of 240-270 °C for [Fe 2MnO(O 2CCh 2) 6(h 2O) 3], 290-320 °C for [Fe 3O-(O 2CCh 3) 6(h 2O) 3D, 300-330 °C for [Fe 2CoO(O 2CCh 3) 6(h 2O) 3] and 320-350 °C for [Fe 2NiO(O 2CCh 3) 6(h 2O) 3], indicating the lowering sequence of the activity of active species. At the same time it has been shown that this activity may come from the joined contributions of both the coordinating capability of the hetero-metals in the complexes and their structural factors. On the basis of the TGA, DTA and EI-MS data, the composition of the active fragments has been tentatively inferred as [Fe 2MnO-(0 2CCh 3) 3-2].

关键词：三元配合物过渡金属配合物乙酸探测反应铁锰钴镍

Dietary fibre enrichment of supplemental feed modulates the development of the intestinal tract in suckling piglets

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Journal of Animal Science and Biotechnology 2020年第1期11卷 183-193页

作者： h.M.J.Van hees M.Davids D.Maes S.Millet S.Possemiers L.A.den hartog T.A.T.G.van Kempen G.P.J.Janssens Department of Nutrition Genetics and EthologyGhent UniversityMerelbekeBelgium Research and Development Trouw NutritionAmersfoortThe Netherlands Department of Internal and Vascular Medicine Amsterdam University Medical CentreAmsterdamThe Netherlands Department of Reproduction Obstetrics and Herd HealthGhent UniversityMerelbekeBelgium ILVO Eenheid DierMelleBelgium BioActor MaastrichtThe Netherlands Animal Nutrition Wageningen University and ResearchWageningenThe Netherlands North Carolina State University RaleighNCUSA.

Background:Commercial pre-weaning diets are formulated to be highly digestible and nutrient-dense and contain low levels of dietary *** contrast,pigs in a natural setting are manipulating fibre-rich plant material from a young ***,dietary fibre affects gastrointestinal tract(GIT)development and health in older *** hypothesised that supplemental diets that contain vegetal fibres are accelerating GIT development in suckling piglets in terms of size and *** d 2 of life,sow-suckled piglets had access to a low fibre diet(CON),a diet with a fermentable long-chain arabinoxylan(lc-AXOS),a diet with a largely non-fermentable purified cellulose(CELL),or a diet containing both *** the initial 2 weeks,the control diet was a high-density milk replacer,followed by a dry and highly digestible creep *** weaning at 25 d,15 piglets from each treatment group,identified as eaters and originating from six or seven litters,were sacrificed for post-mortem examination of GIT morphology,small intestinal permeability and metabolic profile of the *** microbiota composition of the mid-colon was evaluated in a sub-set of ten ***:No major statistical interactions between the fibre sources were *** consumed the fibrecontaining milk supplements and creep diets *** size and small intestinal permeability was not *** intestinal fill was increased with lc-AXOS only,while relative large intestinal weight was increased with both fibre sources(Ph and tended to increase ileal DM content compared to CON(Phe concentration of volatile fatty acids was increased in the caecum(Phe microbiota composition showed a high individual variation and limited dietary ***,CELL induced minor shifts in specific genera,with notable reductions of Escherichia-sh

关键词： Dietary fibre Gut maturation Gut microbiota Suckling piglets

植物蛋白质的初步研究[I] 向日葵种子蛋白质和棉子蛋白质的氨基酸组成

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东北人民大学自然科学学报 1957年第2期 107-114页

作者：陶慰孙沈雨生张惠祥孔成喆

从本世纪初Osborne开始注意到植物蛋白貭的重要性之后,到现在这许多年来对它们的研究还是不太多的.近年来***(1945)用酵母的酶水解的方法研究过向日葵粕中的氨基酸,他分析出十二种氨基酸并测出它的含量。***(1948)用鹼提取酸沉淀的方法... 详细信息

从本世纪初Osborne开始注意到植物蛋白貭的重要性之后,到现在这许多年来对它们的研究还是不太多的.近年来***(1945)用酵母的酶水解的方法研究过向日葵粕中的氨基酸,他分析出十二种氨基酸并测出它的含量。***(1948)用鹼提取酸沉淀的方法分出向日葵种子蛋白貭,同时研究过这种蛋

关键词：向日葵种子初步研究棉子氨基酸氨基羧酸蛋白质

Src homology 2 domain-containing inositol-5-phosphatase 1 （shIP1） negatively regulates TLR4-mediated LPS response primarily through a phosphatase activity- and PI-3K-independent mechanism

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第二军医大学学报 2006年第1期27卷 45-45页

作者： An h Xu h Zhang M Zhou J Feng T Qian C Qi R Cao X Institute of Immunology Second Military Medical Universlty Shanghai 200433 China

Src homology 2 (sh2) domain containing inositol 5 phosphatase 1 (shIP1) plays important roles in negatively regulating the activation of immune cells primarily via the phosphoinositide 3 kinase (PI-3K) pathway by catalyzing the PI-3K product Ptdlns-3,4,5P3 (phosphatidylinositol 3,4,5-triphosphate) into Ptdlns-3,4P2. however, the role of shIP1 in Toll-like receptor 4 (T1.R4)-mediated lipopolysaccharide (LPS) response remains unclear. here we demonstrate that shIP1 negatively regulates ***-induced inflammatory response via both phosphatase activity-dependent and -independent mechanisms in macrophages. shIP1 becomes tyrosine phosphorylated and up-regulated upon LPS stimulation in RAW264. 7 macrophages. shIPl- specific RNA-interfering and shIP1 overexpression experiments demonstrate that shIP1 inhibits ***-induced tumor necrosis factor alpha (TNF-alpha) and interleukin 6 (IL-6) production by negatively regulating the LPS-induced combination between T1.R4 and myeloid differentiation factor 88 (MyD88) ; activation of Ras (p21^ras protein), PI-3K, extracellular signal-regulated kinase 1/2 (ERK1/2), p38, and c-Jun Nh2-terminal klnase (JNK) ; and degradation of lkappaB-alpha. shIP1 also significantly inhibits *** induced mitogen-activated protein kinase (MAPK) activation in TLR4-reconstitited COS7 cells. Although shIPl-mediated inhibition of PI-3K is dependent on its phosphatase activity, phosphatase activity-disrupted mutant shIP1 remains inhibitory to LPS-induced TNF-alpha production. Neither disrupting phosphatase activity nor using the PI-3K pathway inhibitor I.Y294002 or wortmannin could significantly block sh1P1-mediated inhibition of LPS-induced ERK1/2, p38, and JNK activation and TNF-alpha production, demonstrating that shIP1 inhibits LPS-induced activation of MAPKs and cytokine production primarily by a phosphatase activity- and PI-3K-independent mechanism.

关键词：同源关系肌醇-5-磷酸酶1 酶活性生物学

Removal of Nitrogen Dioxide and Sulfur Dioxide from Air Streams by Absorption in Urea Solution

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Journal of Environmental Protection 2011年第2期2卷 175-185页

作者： Mahmood M. Barbooti Neran K. Ibraheem Awni h. Ankosh 不详

The study focuses on the absorption rates of NO2, SO2 and a mixture of these two acid gases into urea solution in packed bed column. The absorption rate was studied as a function of absorbent temperature, urea concentration and acid gas concentration. The influence of liquid temperature between 10 - 40?C, urea concentration between 0.1 - 0.5 M and acid gas concentration NO2 between 100 - 1000 ppm (191 - 1910 mg/m3), SO2 between 500 - 2500 ppm (1310 - 6530 mg/m3) were investigated. The mass gas flow rate of 20.646 (kg/***) at 25?C and the absorption rate were determined by measuring the NO2 and SO2 concentrations in the inlet and outlet streams of the absorptioncolumn. The absorption rate of SO2 increases with the decrease of temperature of absorbent (urea solution) and with the increase of the urea concentration. The presence of NO2 in the effluent gas stream lowers the absorption rate of SO2 in urea solution due to the fast reaction of NO2 with urea as compared with SO2. The absorption rate of NO2 decreases as the urea concentration exceeds 0.4 mol/l and for NO2 gas concentration of 100 ppm due to the decrease the diffusivity of the gas. The experimental data were analyzed using dimensionless analysis to find the correlation of mass transfer coefficient in the packed column sh (h / dp)1.2 = 4.19*10–2 *(G' dp / μg)0.87 (μg / ρg DAB)0.60 The results confirmed the hypothesis that the absorption is accompanied with chemical reaction. Also it is found the increasing the temperature of absorbent solution the absorption rate of two gases is decreases. The mass transfer coefficient models are in good agreements with the Kramer’s equation.

关键词： Sulfur Dioxide Removal Nitrogen Dioxide Removal Column Absorption Removal of Acid Gases Air Pollution Prevention

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干热处理对心里美萝卜种子活力的影响

中国蔬菜 1999年第3期3卷 20-22页

作者：孟淑春孔祥辉北京市农林科学院蔬菜研究中心

对不同基础含水量的心里美萝卜种子进行７６℃干热处理，结果表明其发芽势、发芽率、苗长和活力指数之间均有显著性差异，含水量高的种子受到的不利影响明显大于含水量低的种子，且这种影响随干热处理时间的延长而加重。７６℃干热处理... 详细信息

对不同基础含水量的心里美萝卜种子进行７６℃干热处理，结果表明其发芽势、发芽率、苗长和活力指数之间均有显著性差异，含水量高的种子受到的不利影响明显大于含水量低的种子，且这种影响随干热处理时间的延长而加重。７６℃干热处理心里美萝卜种子安全的含水量为６．９％（湿基，下同），安全的处理时间为１２ｈ（小时）。若含水量低到２．９％时，安全的处理时间可延长到４８ｈ（小时）。

关键词：心里美萝卜种子含水量干热处理种子活力