铜离子和镍离子对绿泥石的抑制作用及机理

通过浮选实验、动电位测量、ICP离子浓度测试及溶液化学计算,研究铜离子和镍离子对绿泥石浮选的影响,并考察其作用机理.结果表明,绿泥石具有一定的天然可浮性,一定pH值条件下铜离子和镍离子能够水解生成亲水的氢氧化物沉淀,通过静电作用吸附在绿泥石表面,抑制绿泥石的浮选;在较高pH条件下,生成的氢氧化物沉淀与绿泥石表面电性相同,吸附量较少,抑制效果较弱.     

东营凹陷砂岩储层自生高岭石发育特征与成因机制

通过大量薄片鉴定、岩心观察以及扫描电镜、粘土矿物粉晶衍射等分析测试手段,对东营凹陷砂岩储层中发育的高岭石的分布、产状以及镜下特征等进行了分析。结果表明,研究区砂岩储层中高岭石有自生和陆源两种成因。自生高岭石在储层中较为常见,其微观特征表现为结晶形态完整,呈典型的书页或蠕虫状充填于粒间孔和长石颗粒溶孔内,在铸体薄片中可见自生高岭石集合体呈“斑状”的聚集充填特征。陆源高岭石在研究区较为少见,一般在浅层出现,是在沉积过程中与碎屑颗粒等非粘土矿物同时形成。在上述研究的基础上,对自生高岭石成因机制进行了讨论,认为东营凹陷砂岩储层中长石类矿物的溶蚀作用是自生高岭石形成的主要物质来源。研究区粒度大、分选好的砂岩储层中高岭石含量较高,说明除酸性的流体环境和一定的物质供应外,流体动力条件也是自生高岭石形成的重要控制因素。     

Ultrasound Enhanced Sanitizer Efficacy in Reduction of Escherichia coli O157 : H7 Population on Spinach Leaves

ABSTRACT:  The use of ultrasound to enhance the efficacy of selected sanitizers in reduction of  Escherichia coli  O157 : H7 populations on spinach was investigated. Spot-inoculated spinach samples were treated with water, chlorine, acidified sodium chlorite (ASC), peroxyacetic acid (POAA), and acidic electrolyzed water with and without ultrasound (21.2 kHz) for 2 min at room temperature. The effects of ultrasound treatment time and acoustic energy density (AED) were evaluated at an ASC concentration of 200 mg/L. The effect of ASC concentration, with a fixed AED of 200 W/L, was also examined. Microbial analysis indicated that ASC reduced  E. coli  O157 : H7 population by 2.2 log cycles over that of water wash, while the reduction from other sanitizers was about 1 log cycle. Ultrasonication significantly enhanced the reduction of  E. coli  cells on spinach for all treatments by 0.7 to 1.1 log cycle over that of washes with sanitizer alone. An increase in the ASC concentration enhanced the efficacy of the combined treatment of ASC and ultrasonication, especially at ASC concentrations of < 300 mg/L. Increasing the ultrasound treatment time from 0 to 4 min and AED from 0 to 500 W/L were both effective in increasing the effectiveness of the ASC and ultrasound combined treatments. In addition,  E. coli  O157 : H7 inoculated on the underside of spinach leaves (rough side) were more difficult to remove than those inoculated on the upper side (smooth side).     

济阳坳陷古近系深层自生矿物及其与孔隙发育的关系

通过岩石薄片鉴定、粘土矿物X-衍射分析、镜质体反射率和油层物性分析等手段,结合区域油气地质研究成果,对济阳坳陷古近系沙河街组三段—四段深部碎屑岩储层自生矿物演化特征与次生孔隙发育带的关系进行了研究。结果表明,沙三段深部储层埋深3150～3600m处次生孔隙主要与碳酸盐类等酸溶性组分的溶蚀有关,埋深4250～4500m处的次生孔隙主要成因于碱性溶蚀作用。沙四段次生孔隙发育带（埋深3350～3600,3950～4200和4500～4900m）主要与还原条件下酸溶性矿物的溶蚀有关;埋深5600～5700m处次生孔隙的发育主要与碱溶性组分的溶蚀有关。车镇凹陷埋深4400～4700m处的高岭石低值带、伊利石含量高值带与次生孔隙发育带对应。东营凹陷北带和渤南洼陷深层绿泥石高值带与孔隙带发育有较好的一致性,且与伊利石含量呈消长关系。渤南洼陷在埋深3500～4800m处存在明显的粘土矿物转化异常带,且伊/蒙混层比高值带与绿泥石激增带及次生孔隙带具有较好的一致性。     

南芬露天矿绿泥角闪岩吸水及强度软化规律

研究表明降雨是诱发矿山边坡失稳变形破坏的重要因素,主要通过降低潜在滑动面(带)岩体强度诱发滑坡。国内外学者对南芬露天铁矿下盘滑坡机理和稳定性评价开展了大量研究,取得了丰富的研究成果。然而,所有研究成果证明该边坡潜在滑动面(带)岩体吸水性较弱,水通过何种途径影响边坡稳定性机理不清晰。采用自主研发的"软岩气态水吸附智能测试系统",对潜在滑动面(带)上分布的绿泥角闪岩进行吸水软化实验,揭示岩石的吸水特性及吸水后的强度衰减规律;运用Image-Pro Plus专业图像处理技术,分析其SEM微观图像;结合绿泥角闪岩的压汞实验结果,揭示其微观孔隙结构特征与岩石吸水特性之间的相互关系。分析结果表明:(1)绿泥角闪岩吸水特性是一个在短时间内快速上升而后下降达到均匀饱和的过程;(2)影响绿泥角闪岩吸水特性的主要因素是岩石样品的孔隙结构特征而非黏土矿物含量;(3)岩石的孔隙累计体积与其吸水特性之间存在正相关关系;(4)集中分布的孔隙直径越小,占据的比例越大,则岩石的吸水能力越差;(5)绿泥角闪岩的吸水率与单轴压缩强度以及弹性模量呈负相关关系。上述研究结果可为南芬露天矿降雨诱发顺层石质滑坡的防治提供理论依据。     

致密砂岩气储层微观孔隙及成岩作用特征—— 以川西新场地区须五段为例

为了更加准确地在川西新场地区三叠系须家河组五段中寻找有效储集体,利用岩石薄片、铸体薄 片、扫描电镜和微米 CT 扫描等资料,结合储层物性资料,对川西新场地区须家河组五段致密砂岩储层的 岩石学、微孔隙空间分布、成岩作用和储层物性等特征及储集空间类型进行了研究。 结果表明：须五段致 密砂岩储层岩石类型为岩屑砂岩和岩屑石英砂岩,储层超致密,储集空间为纳米级晶间孔、微米级溶蚀 孔及成因不同的微裂缝,其中晶间孔为储集空间的主体;综合岩心微米 CT 扫描结果发现,有机质丰度在 一定程度上控制了孔隙的发育和分布,孔隙度随有机质丰度的增大而增大;微孔隙的形态和分布影响了 储层的连通性,其集中连片分布优于分散孤立分布。 压实、交代和胶结等成岩作用是导致砂岩致密化的 重要因素,溶蚀作用对改善储层物性有一定的作用,但对砂岩孔隙度改变不大。     

鄂尔多斯盆地三叠系延长组伊利石包膜成因及其地质意义

通过系统分析延长组伊利石包膜的成因及其地质意义,开展了薄片分析、扫描电镜观测及能谱分析,对伊利石包膜的产状、成分、分布及其与绿泥石包膜的关系进行了研究.研究结果表明:①鄂尔多斯盆地三叠系延长组伊利石包膜与自生蒙脱石包膜具有相似的特征,是自生蒙脱石包膜伊利石化的产物;②研究区自生蒙脱石和绿泥石包膜均是火山物质溶蚀的产物,...     

Microbiological and organoleptic characteristics of beef trim and ground beef treated with acetic acid, lactic acid, acidified sodium chlorite, or sterile water in a simulated commercial processing environment to reduce Escherichia coli O157:H7 and Salmonella

The objective of this study was to validate the effectiveness of acetic and lactic acids (2% and 5%), acidified sodium chlorite (1000 ppm), and sterile water in reducing Escherichia coli O157:H7 and Salmonella Typhimurium in inoculated beef trim in a simulated processing environment. Samples were collected to assess microbial characteristics at three processing points. Results from this study indicate that all treatments, including sterile water, reduced pathogen concentrations (P < 0.05) of both E. coli O157:H7 and Salmonella Typhimurium in ground beef up to 0.5 and 0.6 log by 24 h, respectively. In some cases, there were no significant differences between the antimicrobial treatments and the sterile water using this application method. Triangle sensory test results of non-inoculated beef indicated there were no differences (P < 0.05) in the means of correct responses between controls or antimicrobial treatments at 6 or 24 h. While interventions are important for beef trim, use of the interventions must be validated under industry conditions to ensure proper effectiveness.     

Non-starch polysaccharides from sunflower (Helianthus annuus) meal and palm kernel (Elaeis guineenis) meal—preparation of cell wall material and extraction of polysaccharide fractions

Two different chemical methods, sequential extraction with alkali and sodium chlorite and treatment with 4-methylmorpholine N-oxide (MMNO), were applied to the extraction of non-starch polysaccharides (NSP) from the enzymically deproteinated, water-insoluble cell wall materials of sunflower (Helianthus annuus L) meal and palm kernel (Elaeis guineensis Jacq) meal. The NSP content accounted for 550 g kg^?1 (sunflower meal) and 750 g kg^?1 (palm kernel meal) of the cell wall materials. Neither of the treatments alone was capable of solubilising more than about half of the original NSP. Combined treatment using alkali/chlorite followed by MMNO completely dissolved cell wall material from palm kernel meal, whereas a small residue (40 g kg^?1 of original NSP) was left in sunflower meal. Loss of NSP occurred with both methods (total NSP recovery ranging from 88% for alkali/chlorite extraction of sunflower to 64% for MMNO extraction of palm kernel). Due to differences in solubility revealed upon acidification and/or dialysis, extracts became subdivided into precipitates and soulble fractions. The sugar composition of the resulting fractions enabled a tentative identification of teh major non-starch polysaccharides; sunflower meal was found to contain cellulose, (acidic) xylans, polyuronide-containing fractions and xyloglucan; palm kernel meal was found to contain mannans, cellulose and xylans, with the major part of the mannans originating from the endosperm and the xylans being almost exclusively located in the endocarp.     

Effect of partial delignification of kenaf bast fibers for radiation graft copolymerization

Malaysian kenaf bast fiber was treated by acidic chlorite to be applied for a trunk polymer radiation‐induced graft copolymerization. The delignification conditions such as temperature, reaction time, and sodium chlorite (NaClO₂) loading were optimized from the viewpoints of density, tensile strength, and reactivity of grafting. It was found that delignification condition at 80°C for 6 h with 0.5% NaClO₂ gave 91% of lignin removal from the kenaf bast fibers. In this case, the density, fineness, and tensile strength of the kenaf fiber decreased about 46, 44, and 87%, respectively. Reactivity of grafting was evaluated using 4‐chloromethyl styrene to obtain widely available precursor materials. The partial delignified kenaf with residual lignin less than 2% resulted in degree of grafting of 134%, which is enough for precursor materials. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013