致密砂岩储层黏土矿物特征及敏感性分析—以鄂尔多斯盆地吴起油田寨子河地区长6油层为例

致密砂岩储层孔喉结构复杂、比表面积大,岩石颗粒表面附着大量的黏土矿物,容易受到外来流体的影响,发生颗粒膨胀、迁移、离子沉淀等反应伤害储层,从而影响生产效率。本文以鄂尔多斯盆地吴起油田寨子河地区延长组6段油层为例,通过岩石薄片观察、扫描电镜、X射线衍射仪(X-RD)实验、压汞实验和储层敏感性实验等方法,对研究区储层物性、孔喉结构、黏土矿物特征和储层敏感性类型、伤害程度及敏感性影响因素进行分析。岩心分析实验表明,储层黏土矿物由绿泥石、高岭石、伊利石和伊蒙混层4种矿物组成,影响储层渗透性的敏感性伤害强弱依次为酸敏、水敏、碱敏、盐敏和速敏。并结合实际生产中存在的问题,提出绿泥石富集区域尽量避免储层酸化等改造措施;对伊利石及伊蒙混层含量高、易水敏的地区,压裂改造过程需要提高压裂液砂比,减小压裂液量,从而降低储层损害。     

铝硅酸盐矿物浮选中捕收剂的设计合成及浮选机理的研究

铝土矿中脉石主要为高岭石、伊利石和叶蜡石等铝硅酸盐矿物,可以采用反浮选脱硅即通过选用合适的捕收剂将这些脉石矿物浮出.本文针对某铝土矿,结合Curis2软件中的高岭石晶体模型分析,从亲矿物基和非极性基两方面设计合成多胺类捕收剂DN12.通过浮选实验、浮选溶液化学计算、动电位测定和红外光谱测定研究该新型药剂对铝硅酸盐矿物的浮选作用及其机理.该捕收剂相对于常规捕收剂对铝硅酸盐矿物有更好的捕收效果,有效浮选pH区间为4～10.该捕收剂与铝硅酸盐矿物的作用以静电作用为主,同时也有氢键作用,从而增强了对矿物的捕收能力。     

南票煤田热变煤中粘土矿物变化特征的研究

本文采用X射线分析方法，研究了南票煤田热变煤中粘土矿物的变化特征，由此得出该处岩石浆侵入时对煤层的影响范围和天然焦的形成温度。     

The physiological and nutritional importance of dietary fibre

Summary Fibrous material is an integral part of the daily diet, and it exerts direct physiological effects throughout the gastrointestinal tract, in addition to affecting metabolic activities more indirectly. The interplay of these effects is responsible for the presumed desirable influence of fibre on weight regulation, carbohydrate and lipid metabolism, and on colon function. Numerous mechanisms of action have been identified which are related to the type and the physicochemical nature of the fibre. This review concentrates mainly on the serum cholesterol-lowering effect of dietary fibre, its colonic fermentation, and finally on some possible adverse effects that one should be aware of when consuming high amounts of dietary fibre.     

矿物分形生长的动力学模型与数值模拟

本文通过考虑离子电位、环境温度以及噪声等的影响,建立了一个矿物分形生长的DLA模型.在300×300的正方格子中心处放置一个种子构成生长中心,吸引域设置为菱形,主要考虑了三个参数的影响,其中总体的表面粘附几率为Pg,范围为0~99%,用来消除噪声的影响,模拟矿物的结晶生长速度与矿物结构的关系;吸附距离d变化范围为0~9单元距离,用来模拟离子电位对矿物生长的影响;填充间隔s的变化范围为0.00~5.00单元距离,表现为环境温度对矿物生长体系的影响.进行了三组模拟,分别是固定其中2个参数,改变另一个参数.结果表明,DLA集团的分维值随模拟参数成规律性的变化,分形维数在一定的条件下随着Pg的降低、d和s的增大而增大,矿物的结构也随之从浸染状、星散状或放射状逐渐过渡到团块状.该模型只是对三维分形生长的二维平面模拟,不能完全反映整个矿物在三维受限空间中聚集生长的复杂动力学.     

斜环永磁高梯度磁选机的原理及应用

介绍新型斜环永磁高梯度磁选机的基本结构,分析磁性矿粒在复合力场中的受力和捕获机理,测试该设备对某铁矿尾矿的磁选效果。该磁选机为永磁磁系,分选环为倾斜配置且分选环倾斜角度和转速可调;分选时,磁介质在底部磁场区捕收磁性矿粒,旋转到顶部非磁场区冲洗卸矿。研究结果表明:调节分选环的倾斜角度可改变磁性矿粒所受各作用力的大小,从而调节磁选粒度的下限和磁选作业的回收率;当原矿铁品位为17.81%时,经一次磁选可获得回收率为65.05%、全铁品位为29.53%的磁选精矿。该磁选机设计合理、节能,可实现连续给矿、分选和排矿。     

Oleophobic modification of clay minerals to improve encapsulation ratios of shape-stabilized phase change materials: A universal method

Liquid-solid phase change materials (PCMs) show reversible storage and release of latent heat, which has attracted extensive interests in applications for thermal energy storage. However, stubborn leakage issue may cause corrosion and extra thermal resistance. The non-wettability of melted paraffin on the oleophobic surface of diatomite has been reported by authors earlier, and the result showed that the encapsulation ratio (84.5%) of diatomite@paraffin shape-stabilized PCM greatly increased. Here, in order to prove this method equally applicable to other PCMs and porous natural clay minerals, diatomite and sepiolite were oleophobically modified to encapsulate melted stearic acid and paraffin, to form shape-stabilized PCMs. The results showed that the encapsulation ratios of 67.8% and 56.6% for diatomite@stearic acid and sepiolite@paraffin were higher than that reported in the references (28.9% and 36.8%). In addition, the encapsulation ratios of diatomite-based shape-stabilized PCMs can be also increased using different PCMs, such as n-octadecane and polyethylene glycol via the same approach. Therefore, this is a universal method for improving encapsulation ratios of shape-stabilized PCMs.     

A high-resolution clay mineralogical record in the northern South China Sea since the Last Glacial Maximum,and its time series provenance analysis

High-resolution clay mineralogical analysis of Core MD05-2904 in the northern South China Sea (SCS) covering the period since the Last Glacial Maximum shows that illite (29%–48%), smectite (14%–45%), chlorite (17%–28%), and minor kaolinite (6%–14%) comprise the clay mineral assemblage, and that time series variation does not present glacial-interglacial cyclicity. Provenance analysis indicates three end-member sources: almost all smectite derives from Luzon, all kaolinite is sourced from the Pearl River, and illite and chlorite originate from both the Pearl River and Taiwan. By comparing clay mineral compositions in surface sediments from the three major source areas and of the SCS, we reconstructed a time series of clay mineral contribution from the major provenances to the northern slope of the SCS using the linear separation method for illite crystallinity. There were three stages of provenance change. (1) During 24.1–17.5 ka BP, contributions from Taiwan and Luzon were similar (30%–40%), while that from the Pearl River was only 25%. (2) During 17.5–14.0 ka BP, the contribution from Luzon decreased rapidly to 20%–25%, while that from Taiwan increased to 35% from an average of 25% at 18 ka BP, and that from the Pearl River increased largely to 40%. (3) During the Holocene, differences in contributions from the three major provenances increased: the contribution from Luzon increased slightly and then remained at 27%–35%, that from Taiwan increased rapidly and then remained at 55%–60%, and that from the Pearl River decreased to 15%. The change in clay mineral contributions from different provenances is influenced mainly by clay mineral production, monsoon rainfall denudation, oceanic current transport, and sea-level change.     

W油藏粘土矿物特征及油层低阻成因

W油藏Z1油组为高孔低渗低阻油藏,低阻油层的地质成因复杂多样。依据Z1油组储层发育特征,研究了储层粘土矿物的类型、颗粒的分布形式和泥质含量,以及上述粘土矿物特征对Z1油组低阻的影响。研究发现,Z1油组低阻层段的粘土类型以伊蒙混层为主,其相对含量高;粘土颗粒较均匀地成薄膜状、絮状分布;平均泥质含量高。粘土矿物组构产生的附加导电性和高泥质含量是影响Z1油组低电阻率的重要因素之一。