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1.
原煤中腐植酸的活化处理研究   总被引:1,自引:0,他引:1  
实验研究原煤中腐植酸各种活化处理方法并进行分析比较,提出可应用于肥料领域的腐植酸活化处理优化方案是碳铵+氨水处理,处理后水溶性腐植酸占游离腐植酸比例达~70%,处理成本仅为260元/t.  相似文献   

2.
氮磷钾追施对夏大豆产量的影响   总被引:1,自引:0,他引:1  
氮肥运筹和磷钾肥初花期追施试验表明:适量的氮磷钾肥后移不仅能提高大豆产量,且有一定的经济效益。增产幅度和效益是氮肥后移>磷肥后移>钾肥后移。氮肥追施适宜比例为50%左右,宜初花期一次追施或初花期、鼓粒期二次追施;30%以上的磷钾肥可后移至初花期追施。生产上应提倡氮肥后移,在基施磷钾肥不足时还应追施磷钾肥。  相似文献   

3.
Characterization of soybean protein isolates The effect of calcium presence   总被引:1,自引:0,他引:1  
Results of a study of the effect of calcium addition on polypeptide composition, hydrophobicity, sulfhydryl content, thermal stability, enthalpy of denaturation, and water solubility of soybean protein isolates suggest that the addition of small amounts of calcium (1.23–5.0 mg/g protein) induced the formation of α, α′ soluble aggregates, whereas large amounts (5.0–9.73 mg/g protein) induced the selective insolubilization of the glycinin fraction. The addition of this ion also produced thermal stabilization of the soybean proteins, mainly the glycinin fraction, and increased the enthalpy of denaturation. A decrease in the surface hydrophobicity of proteins with increasing calcium content was also observed. The results obtained suggested the existence of specific calcium-soy protein interactions, especially with the glycinin fraction.  相似文献   

4.
The stability parameters of 22 samples of soybean oil produced in Mexico were determined. Samples were analyzed for moisture, color, free fatty acids, peroxide value, p-anisidine value, fatty acid profile, metals, flavor, and Rancimat test for oxidative stability. Results obtained were compared with the stability parameters of soybean oil sproduced in the United States and Costa Rica. The fatty acid profile in all samples analyzed corresponded to the expected profile for a 100% soybean oil. Sixty-four percent of the oils had oxidative stabilities similar to those reported for soybean oils from the United States and Costa Rica. This suggests that in spite of the good quality, the soybean oil production process in Mexico needs further improvement. Especially important is maintaining appropriate control during the degumming and bleaching steps. Special consideration should be given to preserving the natural antioxidants present in the oil.  相似文献   

5.
Raw glycerol, the main by‐product of the bio‐diesel production process, was converted to 1,3‐propanediol by Clostridium butyricum F2b. In batch cultures, 47.1 g dm?3 of 1,3‐propanediol were produced. Continuous cultures were conducted at a constant dilution rate (= 0.04 h?1) and various inlet glycerol concentrations with 1,3‐propanediol produced at levels up to 44.0 g dm?3. At increasing glycerol concentrations in the inlet medium, biomass yield decreased. This decrease was attributed to the microbial metabolism being directed towards the biosynthesis of organic acids (and hence carbon losses as CO2) instead of biochemical anabolic reactions. An autonomous analytical model was developed, and quantified the effect of inlet glycerol concentration on the production of biomass and metabolites. Indeed, high inlet substrate concentrations positively affected the biosynthesis, principally of butyric acid and to a lesser extent that of acetic acid. In contrast, at increased glycerol concentrations, the relative increase of 1,3‐propanediol production per unit of substrate consumed was lower as compared with that of acetic and, mainly, butyric acid. This could be explained by the fact that the butyric acid pathway represents an alternative and competitive one to that of 1,3‐propanediol for re‐generation of NADH2 equivalents in the microbial cell. Copyright © 2004 Society of Chemical Industry  相似文献   

6.
生漆改性研究及漆酚金属高聚物   总被引:12,自引:6,他引:6  
本文综述了生漆改性研究的概况 ,总结了漆酚金属高聚物的合成方法、结构特征及其主要性能 ,提出了今后生漆改性研究的发展方向和重点内容  相似文献   

7.
陈旭峰 《水泥》2003,(12):37-39
介绍了生料成分在线控制对提高生料均化效果的作用、各类在线控制系统的特点及国产在线钙铁仪的实际应用效果,尤其是针对无原料预均化和生料均化库能力不足的水泥生产线,给出了提高生料均化效果较为经济有效的解决途径。  相似文献   

8.
我国橡胶工业原材料进展   总被引:1,自引:0,他引:1  
许春华 《弹性体》2001,11(5):51-56
概述了我国橡胶工业原材料-天然橡胶,合成橡胶,骨架材料,碳黑和橡胶助剂的现状及发展趋势。  相似文献   

9.
The oxidative stability of soybean oil triacylglycerols was studied with respect to composition and structure. Crude soybean oils of various fatty acid and triacylglycerol composition, hexane-extracted from ground beans, were chromatographed to remove non-triacylglycerol components. Purified triacylglycerols were oxidized at 60°C, in air, in the dark. The oxidative stability or resistance of the substrate to reaction with oxygen was measured by determination of peroxide value and headspace analysis of volatiles of the oxidized triacylglycerols (at less than 1% oxidation). The correlation coefficients (r) for rates of peroxide formation (r=0.85) and total headspace volatiles (r=0.87) were related positively to oxidizability. Rate of peroxide formation showed a positive correlation with average number of double bonds (r=0.81), linoleic acid (r=0.63), linolenic acid (r=0.85). Rate of peroxide formation also showed a positive correlation with linoleic acid (r=0.72) at the 2-position of the glycerol moiety. A negative correlation was observed between rate of peroxide formation and oleic acid (r=−0.82). Resistance of soybean triacylglycerols to reaction with oxygen was decreased by linolenic (r=0.87) and increased by oleic acid (r=−0.76)-containing triacylglycerols. Volatile formation was increased by increased concentration of linolenic acid at exterior glycerol carbons 1,3 and by linoleic acid at the interior carbon 2. Headspace analysis of voltiles and high-performance liquid chromatography of hydroperoxides indicated that as oxidation proceeded there was a slight decrease in the linolenic acid-derived hydroperoxides and an increase in the linoleic acid-derived hydroperoxides. The oxidative stability of soybean oil triacylclycerols with respect to composition and structure is of interest to the development of soybean varieties with oils of improved odor and flavor stability. Presented at the 81st Annual American Oil Chemists' Society Meeting, Baltimore, MD, April 18–21, 1990.  相似文献   

10.
我公司不断探寻新型低成本可替代原料。粉煤灰为粉状物料且水分较高,容易堵下料口,造成下料困难,经过多次实验发现,煤矸石与湿粉煤灰成分相近,其为块状物料,易于输送,价格较湿粉煤灰更为低廉,具有较高的资源替代性。煤矸石可替代现有的铝质校正材料湿粉煤灰进行生料配料。使用煤矸石配料能减少煤的配入量,使系统实物煤耗降低约0.5 kg/t;煤矸石到厂价格较湿粉煤灰价格便宜20元/t左右,可有效降低生料配料成本,具有较好的经济效益。煤矸石中硫含量较高且波动较大,可能造成烧成系统结皮、尾气硫超标等,使用时应加强煅烧工艺控制,并做好硫排放控制措施。  相似文献   

11.
王继勇 《水泥工程》2017,30(6):21-23
福建省泉州美岭水泥有限公司二线生料立磨因超产幅度较大,运行风量较高,立磨进出口压差偏高,导致循环风机、立磨选粉机运行负荷也偏高。为优化立磨运行技术经济指标,该公司对立磨选粉机结构、立磨风环调风板以及立磨下壳体风道等进行了技术改造。原料立磨减阻改造后,立磨压差下降,单位生料循环风机电耗降低0.82 kWh/t,经济效益明显。  相似文献   

12.
大力发展优质合成耐火原料   总被引:16,自引:9,他引:7  
进入新世纪,应根据我国耐火原料资源丰富的优势,加快发展有自己特色的矾土基和镁砂基的优质合成耐火原料.它们可分为均质料、改性料、转型料三种类型.  相似文献   

13.
The present study was undertaken to evaluate the effect of oxidative damage due to excessive protein diet on pancreas function in mice. For this purpose, thirty male (C57BL/6J) mice were randomly divided into three groups and fed on different diets as follows: group 1 was fed on a normal diet, group 2 was fed on an excessive protein diet and group 3 was fed on an excessive protein diet supplemented with 0.06 g/kg cysteamine. Each group was fed for 2 weeks, and then pancreas samples were collected to examine oxidative and antioxidant parameters and pancreas function. The results showed that ingestion of an excessive protein diet markedly increased contents of malondialdehyde (MDA) and decreased T-AOC and activities of antioxidants SOD and GSH-Px, compared with a normal diet (P < 0.05). Pancreas weight and concentration of protein, DNA and RNA were significantly higher (P < 0.05), digestive enzyme activities were significantly lower and levels of somatostatin and insulin were higher in mice fed with an excessive protein diet than those fed with a normal protein diet. In the group fed with excessive protein diet supplemented with cysteamine, oxidative stress was mitigated and pancreas function was improved. These data demonstrate that excessive protein ingestion could increase oxidative damage of free radicals on pancreas function through destroying the balance of oxidants and antioxidants.  相似文献   

14.
李小斌  唐时健  刘桂华 《化学工程》2006,34(7):17-20,37
为了降低烧结法氧化铝生产中烧结过程的能耗,从流变学角度测量生料浆在6个不同剪切速率下的剪切应力,通过其流变曲线,研究了生料浆的触变性及水分质量分数、温度、表面活性剂对生料浆流变性的影响。结果表明:含水质量分数为35%的生料浆具有触变性;随着生料浆含水质量分数从34.7%增加到39.7%、温度从40℃升高到80℃,添加适当表面活性剂R—COONa,可降低生料浆的屈服应力和表观粘度,使生料浆的流动性得到一定改善。  相似文献   

15.
罗毅  李瑞金  孙永强 《日用化学工业》2012,42(2):101-103,128
为探讨椰子油乙氧基化物-36EO(COE-36)和大豆油乙氧基化物-42EO(SOE-42)对小鼠肝脏的脂质过氧化作用,采用腹腔注射技术,测定COE-36处理组、SOE-42处理组、氯化镉阳性对照组(小鼠单位体质量的氯化镉用量为2.5μg.g-1)和生理盐水阴性对照组小鼠肝脏超氧化物歧化酶(SOD)、过氧化氢酶(CAT)活性和丙二醛(MDA)生成量。结果表明,氯化镉显著抑制了小鼠肝脏SOD和CAT活性,增加了MDA生成量;在所测3个指标中,COE-36和SOE-42的3个用量组(以小鼠单位体质量的用药量计)与生理盐水阴性对照组相比均无显著性差异;与氯化镉阳性对照组相比,不同用量COE-36作用下SOD和CAT活性变化、不同用量SOE-42作用下CAT活性变化以及低用量(3 mg.g-1)COE-36或SOE-42作用下MDA生成量变化均有显著性差异,说明在所试用量(3~5 mg.g-1)下,这2种表面活性剂不会引起小鼠肝细胞的脂质过氧化。  相似文献   

16.
The purpose of this study was to evaluate the antioxidant nature of tea polyphenol on S180 cells induced liver cancer in mice. In the present study, hepatocellular carcinoma was induced by tumor transplantation of liver in situ. The antitumor activity of tea polyphenol has been determined in vivo in hepatocellular carcinoma mice after treatment of drug (50, 100, 150 mg/kg body weight) by gavage for 20 days. Results showed that a significant increase in serum aspartate transaminase (AST), alkaline phosphatase (ALP), alanine aminotransfere (ALT), malondialdehyde (MDA) level, decrease in serum white blood cells (WBC), serum total protein (TP), albumin (ALB), A/G, tumor necrosis factor-α (TNF-α) and interferon-gamma (IFN-γ), liver reduced glutathione (GSH) levels were observed. In addition, the levels of enzymic and non-enzymic antioxidants were decreased when subjected to S180 cells induction. These altered enzyme levels were ameliorated significantly by administration of tea polyphenol at the concentration of 50, 100, 150 mg/kg body weight in drug-treated animals. These results indicate that the protective effect of tea polyphenol was associated with inhibition of MDA induced by S180 cells and to maintain the antioxidant enzyme levels.  相似文献   

17.
对玻璃原料的水分含量测定方法进行了试验,用数理统计法对试验误差进行了分析,提出了合理的分析误差标准,对于原料生产、商务贸易以及玻璃配料控制均具有指导意义.  相似文献   

18.
β-Conglycinin is a trimeric protein consisting of three subunits, α,α′,and β, which are N-glycosylated. The α and α′ subunits contain extension regions in addition to core regions common to all subunits. We purified homogeneous trimers consisting of only α, α′, or β from mutant soybean cultivars containing β-conglycinin lacking one or two subunits: α homotrimers from an α′-lacking mutant, α′ homotrimers from an α-lacking mutant, and β homotrimers from an α-and α′-lacking mutant. Structural features and physicochemical functions of the three homotrimers were examined and compared with those of recombinant homotrimers having no N-linked glycans. The native homotrimers have secondary structures very similar to those of the recombinant ones. In analogy with the recombinant homotrimers, the native ones exhibit different thermal stabilities from one another (β>α′>α), and the native α and α′ homotrimers exhibit better solubility, emulsifying ability, and heat-induced association than the native β homotrimer. Further, the N-linked glycans contribute to solubilities of the three subunits at low ionic strength (μ=0.08) and to the emulsifying ability of the native β homotrimer. N-Linked glycans also prevent heat-induced associations of the native α and α′ homotrimers but do not contribute to the secondary structure and the thermal stability of β-conglycinin.  相似文献   

19.
Guangbo Qu  Yi Zhang  Weidong Zhang 《Carbon》2009,47(8):2060-495
Purified carboxylated multiwalled carbon nanotubes (MWCNTs) with different agglomeration propensities were evaluated in mice following a single dose intravenous injection. Both agglomerated and the well suspended MWCNTs were taken up by mononuclear phagocyte system organs. MWCNTs with higher degree of agglomeration were retained in lungs and later in the liver and were not eliminated completely in 28 days, while the well-dispersed ones remained well dispersed and formed fewer aggregates in the lungs and liver, and seemed to be easily eliminated. Persistent accumulation of agglomerated MWCNTs in the lungs caused inflammatory responses while the well-suspended ones did not. Although the elimination of MWCNTs is still to be evaluated quantitatively, the formation of a stable suspension is one of the key requirements for safe applications in medicine.  相似文献   

20.
Bleached and unbleached forms of a rosemary oleoresin (RO) in stripped and nonstripped soybean oil behave both as antioxidant and prooxidant in a light-induced oxidative system. At 0.02 and 0.05% levels, RO had the greatest antioxidant activity, while at 0.01 and 0.5% levels it had the highest prooxidant activity in both stripped and nonstripped soybean oil. Treatment of both soybean oil systems with tertiary butylhydroquinone controlled light-induced oxidation of the oil better than did the oleoresin treatments. The prooxidant activity of the 0.5% RO level was probably due to an excess of prooxidant components being carried into the oil at that level, whereas the reduced antioxidant activity at 0.01% was probably due to the low initial level of active antioxidant components being added to the oil. Published as Journal Series No. 10072, Nebraska Agricultural Research Division, Department of Food Science and Technology, University of Nebraska, Lincoln, NE 68583-0919.  相似文献   

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