沙果不溶性膳食纤维提取工艺的研究

以沙果为原料,采用酶-化学法研究了原料中不溶性膳食纤维的制备工艺.采用单因素试验分别从糖化酶加酶量、酶解时间、碱解pH、碱解温度和碱解时间筛选出影响显著的因素,通过正交试验确定了沙果中不溶性膳食纤维(insoluble dietary fiber,IDF)提取工艺的最佳条件.研究结果表明,沙果中IDF提取的最佳工艺条件为:糖化酶加酶量为0.6%(g/g),酶解温度为60℃,酶解时间为90 min,碱解pH为10,碱解温度为50℃,碱解时间为90 min.     

基于大豆膳食纤维的高黏度样品细菌总数检测方法研究

[目的]研究基于大豆膳食纤维的高黏度样品的细菌总数检测方法.[方法]对大豆膳食纤维样品的前处理过程和培养基选择进行了研究.[结果]在大豆膳食纤维样品的前处理过程中,与普通方法相比,采用称重法和RAININ Pos-D外置活塞式微量移液器量取稀释液所测得的细菌总数较高.3种计数培养基中,采用3M Petriflim<'TM>菌落总数测试片的菌落总数测定结果最好,其次是采用平板计数琼脂,最差是采用TTC营养琼脂;3M测试片和TTC营养琼脂的测定结果的精密度较好、人员计数偏差较小,而平板计数琼脂相对较差.[结论]为检测具有颗粒、高吸水性及高黏度等性质的样品提供了参考.     

粉煤灰中稀土元素提取利用研究进展

稀土元素在现代工业中的作用与日俱增,随着未来需求的日益增长以及传统矿床的逐渐消耗,寻找稀土资源新的来源是全球关注的焦点。近年来,粉煤灰被认为是未来能够提供稀土元素的可替代原料之一,同时,稀土元素提取也被认为是粉煤灰高附加值利用的一个重要方向。要实现粉煤灰中稀土元素的综合利用,提取技术是关键。本文总结了国内外粉煤灰中稀土元素赋存状态、物理富集以及化学提取的最新研究进展,探讨了粉煤灰中稀土元素提取要综合考虑的各种因素,可为从粉煤灰中提取利用稀土元素提供参考,促进粉煤灰的高效循环利用。     

济钢高炉冲渣水余热利用

在济钢1750m3高炉冲渣水池边空地处新建换热站,将高炉冲渣水经渣浆泵提升,送至高效纤维束过滤器过滤,过滤后的冲渣水作为一次水进入高效全焊接板式换热器换热,换热器后的水（洁净的自来水）用于采暖。该方案将二次循环水与冲渣水由板片隔开,保证了二次水的清洁,成功解决了用户暖气片腐蚀、堵塞的难题;回收期较短,为企业节资、节电、节水,并达到了环保的要求;提高了生产工艺效率,降低了生产成本;同时带来显著的社会经济效益。     

磁性高铬铁素体纤维的热稳定性研究

由Cu-11?-4%Cr原位复合丝材硝酸法提取得到高铬铁素体纤维.研究了热处理对高铬铁素体纤维样品结构和磁性的影响.采用X射线衍射和扫描电镜观察分析了样品的结构和形貌,采用振动样品磁强计测试了样品的磁性,利用热重-差热分析比较了不同变形量的高铬铁素体纤维在空气中的热稳定性.结果表明,高铬铁素体纤维的比饱和磁化强度约为114A·m2·kg-1,高铬铁素体纤维在空气中经600℃以上加热1h后,逐渐由铁磁性的α-(Fe,Cr) (BCC结构)固溶体转变为顺磁性的(Fe,Cr)2O3(六方晶系),比饱和磁化强度显著下降;微米级、亚微米级高铬铁素体纤维的热稳定性显著高于微米级多晶铁纤维.     

微生物利用木质纤维原料产木聚糖酶研究现状

木聚糖酶在食品、饲料、造纸等领域具有重要的应用价值,而生产成本是决定微生物木聚糖酶能否实现工业应用的关键因素之一.木质纤维原料富含木聚糖,许多能够利用廉价的木质纤维原料诱导产生木聚糖酶的微生物得到了分离,有效地降低了酶制剂的生产成本.综述了微生物利用木质纤维原料产木聚糖酶的研究现状,重点关注了微生物木聚糖酶的产生、特性及发展前景.     

八钢热电厂化水站高效纤维过滤器的改进

八钢能源中心热电分厂化水站投运前期，高效纤维过滤器产水不能满足后续设备反渗透装置的进水水质要求，给制水设备的正常运转带来了不利影响。在生产实践中逐步积累经验对所存在的问题进行了分析，并介绍了改进措施。     

利用纤维型碳源制备高性能磷酸铁锂

介绍了一种利用新型纤维型碳源制备锂离子电池磷酸铁锂正极材料的方法,与常规碳源相比,纤维型碳源可以在较低的温度下、较短的时间内有效地对磷酸铁锂粉体进行碳包覆,提高电子电导率,从而提高整体电化学性能.该方法具有碳源来源广泛,成本较低;烧结温度较低及烧结时间缩短,节省能源;所制备正极材料性能优异,适用于大规模工业化生产.     

煤及其副产物中锗的提取利用研究进展

锗作为高科技新兴产业的高价值稀散元素,已被众多国家列为战略性关键矿产资源,而煤及其副产物中锗资源的提取利用也已成为了行业研究的热点。总结了煤中锗的富集模式与赋存状态,系统分析了煤及其副产物中锗资源的提取利用技术的现状,对比了现有技术的优势与不足,并初步分析了目前研究的难点和未来的发展方向,以期为煤及其副产物中锗的高效提取利用和综合利用奠定基础。     

高炉水淬渣处理及利用技术

钢铁联合企业在生产过程中会产生大量废渣 ,这些废渣如不合理地开发利用 ,将对大气、环境等造成巨大的污染 ,如何合理开发、利用这些二次资源已成为国内外各钢铁企业研究的重点及难点课题。介绍了目前高炉水淬渣的几种处理工艺及特点。     

Soluble and insoluble fiber contents of some Cameroonian foodstuffs

As a result of the lack of reliable data on the fiber content of African foodstuffs, a study to determine the dietary fiber contents (soluble, insoluble and total) on a dry weight basis of a selected variety of major Cameroonian foods was conducted. The influence of processing and preparation methods on the fiber content was also assessed. Vegetables were found to be the richest source of total dietary fiber (57%), followed by legumes and seeds (30%) and fruits (16.5%). Okro (Hibiscus esculenta), plantain (Musa paradisiaca) and beans (Phaseolus spp) showed varietal differences in their soluble and insoluble fiber content, while methods of processing and preparation significantly influenced the fiber content of cassava (Manihot esculenta), corn (Zea mays) and beans.     

废轮胎热解炭黑灰渣中锌提取工艺

废轮胎经煤油预处理后, 经热解生成炭黑, 之后煅烧生成灰渣, 针对废轮胎热解炭黑煅烧后灰渣中锌的提取进行了相关研究, 采用酸溶-分步沉淀法, 最终锌以氧化锌产品回收。分别采用4种无机酸(HCl、HNO₃、H₂SO₄及醋酸)对灰渣进行酸溶处理, 得出盐酸对灰渣酸溶效果最佳; 在此基础上, 考察了酸浓度、液固比(酸体积/炭黑质量)、浸出时间、酸解温度等因素对锌离子浸出效果的影响, 得到锌浸出的优化工艺条件为:酸浓度2 mo1/L、温度20 ℃、浸出时间60 min和液固比6:1 (mL/g), 在此条件下浸出锌离子的浸出率约为91.4%。经分步沉淀法对滤液进行沉淀、煅烧后, 得到纯度约为98.2%氧化锌产品, 灰渣中锌提取率达到81.4%左右。      

Fractionation of human erythrocyte membranes. Presence of the nucleoside transport complex in an insoluble residue

(1) Human erythrocyte membranes, when dialysed against water at pH 9.5, were partly solubilized, losing 80% of the membrane proteins and 65% of the membrane lipids. Sodium dodecyl sulphate gel electrophoresis of the particulate material revealed selective removal of proteins from the membrane. (2) The lipid-rich particulate material remaining retained the ability to bind specifically the nucleoside transport inhibitor, nitrobenzylthioinosine, previously shown to bind selectively to the nucleoside transport mechanism of whole erythrocytes and erythrocyte ghosts.     

Extraction of vanadium from V-Cr bearing reduced residue by selective oxidation combined with alkaline leaching

The extraction of vanadium from the V-Cr-bearing reduced residue formed from the waste water by reduction and neutralization in the process of extracting vanadium from vanadium slag was investigated by selective oxidation combined with alkaline leaching. Vanadium pentoxide is used as the selective oxidant. The effects of leaching temperature, leaching time, solution pH and vanadium pentoxide addition were studied. Under the most suitable conditions including a leaching temperature of 95°C, leaching time of 3?h, solution pH 13.0 and vanadium pentoxide addition of 4.55?wt-%, the leaching of vanadium reached 93.4% and the leaching of chromium was 17.1%.     

The effect of dietary fiber in tube-fed elderly patients

Diarrhea is a common problem with potentially serious consequences for elderly tube-fed patients. A review of the literature indicates that diarrhea has been associated with the use of antibiotics, low blood albumin concentration, and a lack of fiber in the diet. This study documents the observed effect of dietary fiber on the incidence of diarrhea in 50 tube-fed patients. Over a 3-week period, patients who received fiber-containing formula had fewer liquid/loose stools than patients who received fiber-free formula. Nurses who care for elderly, tube-fed patients can help to improve outcomes by advocacy and interdisciplinary collaboration with registered dietitians and primary providers and by teaching assistive staff the importance of accurate recording of bowel function.     

Insoluble dietary fiber of grain food legumes and protein digestibility

The present work aimed to verify the digestibility of cooked whole food grain legumes. Samples of beans (Phaseolus vulgaris and Vigna sinensis), chickpeas (Cicer arietinum) and lentils (Lens culinaris) were used in the experiment. The interrelationship between the insoluble dietary fiber presented in the food grain legumes and the low protein digestibility was studied. The insoluble dietary fiber and the proteic nitrogen presented in the neutral detergent fiber (NDF) were determined. "In vivo" digestibility was performed in rats fed with diets containing cooked grain legumes, casein and protein free diet. The experiments were performed on rats over a period of 21 days. High excretion of nitrogen was observed by rats fed with cooked food grain legumes compared to casein diet. "In vitro" digestibility was performed by enzymatic hydrolysis with pepsin and trypsin. No significant differences was found between "in vivo" and "in vitro" digestibility. The heat treatment caused increased in the values of insoluble dietary fiber by the complexation of its components with protein and aminoacids. The results obtained showed the increased of the insoluble dietary fiber, in the cooked samples compared with raw samples. Significant values of protein nitrogen were found in the NDF, suggested that it was originated by complexation with proteins and aminoacids. This fact contributed to become proteic nitrogen nonavailability decreasing consequently the digestibility of the proteins.     

Simple method for determination of dietary fiber in frozen foods

A simple method was developed for the determination of dietary fiber in multicomponent foods. The method involves dispersing the sample into pH 7.4 phosphate buffer and adding bile and pancreatic enzyme as described. Results were comparable to AOAC methods with correlation coefficients of 86% for multicomponent dinners and 89% for breakfast foods. Coefficients of variation ranged from 7.4 to 20.0% for multicomponent foods and 1.0 to 3.6% for single component foods. In addition, blind duplicate samples had a correlation of 0.99. The described method required less time, labor, and manipulation than AOAC methods.     

Effects of amount and type of dietary fibre (soluble and insoluble) on short-term control of appetite

OBJECTIVE: The calcium (Ca) pump of cardiac sarcoplasmic reticulum (SR) membranes is vulnerable to oxidation and hence likely to be damaged by chlorinated compounds, specifically hypochlorite (NaOCl) and monochloramine (NH2Cl), the most potent oxidants produced upon neutrophil activation. This could occur during prolonged ischemia or myocardial infarction when tissue levels of catecholamines are high. Phospholamban (PLN), the phosphorylatable regulator of the Ca pump, plays a central role in the effects of beta-adrenergic agonists on the heart. The purpose of this study was to investigate a possible role of PLN in determining the pump's sensitivity to NaOCl and NH2Cl. METHODS: Ca-uptake and Ca(2+)-ATPase activities in purified phosphorylated and control canine cardiac microsomes, incubated at increasing concentrations of NaOCl or NH2Cl, were related to the extent of PLN phosphorylation by protein kinase A, which was quantitated by PhosphorImager analysis. RESULTS AND CONCLUSIONS: Our data indicate that microsomal phosphorylation protects the Ca pump fully against 10 microM NaOCl or NH2Cl, which inhibit Ca-uptake by 21-41% when assayed at 25 or 37 degrees C and saturating Ca2+ in unphosphorylated microsomes, and protects partially at higher oxidant concentrations. The protective effect of protein kinase A on Ca-uptake is proportional to the amount of phosphorylated PLN. No comparable protection against similar oxidative damage of the Ca pump is observed when light fast skeletal muscle microsomes, which lack PLN, are incubated under conditions favorable for phosphorylation nor when PLN's inhibition of the cardiac Ca pump is relieved by proteolytic cleavage of its cytoplasmic domain. Our findings contribute toward an understanding of possible endogenous protective mechanisms that may promote calcium homeostasis in myocardial cells in inflammatory states associated with neutrophil activation and may suggest an approach toward development of protective strategies against oxidative damage in the heart.