弱凝胶钻井液成胶剂AM/AMPS/OA_8的合成与表征

针对水平井、大斜度井钻井过程中井眼润滑性、岩屑携带以及钻井速度的影响等问题,通过合理的分子设计,以丙烯酰胺(AM)、2-丙烯酰胺-2-甲基丙磺酸(AMPS)和实验室自制疏水单体丙烯酸正辛醇OA_8为原料,利用胶束聚合法,制备了一种弱凝胶成胶剂AMAMPSOA_8,其结构经1H NMR和IR表征。以AMAMPSOA_8在低剪切速率下的表观粘度为指标设计正交试验,确定最优反应条件为:AM与AMPS摩尔配比为4.8∶1,引发剂用量为单体总质量的0.04%,疏水单体浓度为0.75%,于70℃反应9 h。该条件下,0.5%AMAMPS0A_8聚合物溶液在低剪切速率3 r·min^(-1)下表观粘度可达23 680 mPa·s。利用热分析仪、高温滚子炉、高温高压流变仪对产物性能进行了研究。研究表明:AMAMPSOA_8的抗温性能可达160℃;聚合物溶液体系有明显的触变性,在40 min后溶液切力增加幅度变缓。

煤层注射成胶型抑尘剂影响因素及抑尘效果研究

为解决煤层注水降抑尘技术中水分易流失,开采时注水抑尘效果较差等问题,提出一种既能增加煤层保水率又能改善煤层脆性的抑尘方法:研制出以海藻酸钠(SA)为基质的成胶型抑尘剂,并开展比表面积试验、氮气吸附试验、扫描电镜试验和产尘率试验,研究表面活性剂、黏度及注射压力对成胶型抑尘剂的影响。结果表明:表面活性剂有利于煤层润湿,但对抑尘效果影响较小;抑尘剂黏度增大有利于保水,可使保水时间由10 h提升至30 h,但会导致材料难以进入煤层内部;注射压力对于抑尘剂的抑尘效果具有较大影响,当煤层注射压力较小时,抑尘剂难以快速渗入煤的内部孔隙中,随着压力的增大,抑尘剂逐渐渗入煤孔隙中。当注射压力升至3 MPa后,抑尘效果不再随压力的增加而增加,产尘率由4%降低至2.3%,相对降幅达50%,有效降低了产尘。

成胶型抑尘剂对煤体协同增润效应研究

为从源头控制煤矿开采过程中粉尘的产生,采用文献分析和试验的方法,筛选出润湿和保水性能较好的海藻酸钠单组分抑尘材料,并以此为基础制备出一种以海藻酸钠为主的煤层成胶增润型抑尘剂,其主要成分构成是质量分数为0.25%的海藻酸钠、0.15%的葡萄糖酸内酯、0.15%的乙二胺四乙酸二钠钙和0.1%的十二烷基硫酸钠,同时对制备的成胶型抑尘剂进行含水量、保水率、扫描电镜和比表面积及孔径测定。结果表明:该抑尘剂能够提高煤层的含水量和保水率,含水量比水为抑尘剂处理后的煤高近4倍,保水率比水处理的煤时间延长2倍以上;扫描电镜测试和比表面积和孔径测试表明,成胶型抑尘剂可增强材料对煤体的胶粘作用,且能够进入煤的内部孔隙在煤内外表面均成胶,有效地提高了保湿效果,实现从根本上控制煤体产尘。

水基压裂液的化学添加剂

本文概述了水基压裂液中各种化学添加剂的作用及其在国外的应用和研究情况。指出水溶性的天然聚合物仍是目前主要应用的成胶剂,而合成聚合物成胶剂则正在迅速发展之中。从制备工艺来看,通过使用高温交联剂或 pH 值控制剂的方法实现延缓交联以达到连续混配的目的,是当前发展的重要方向。

超低渗裂缝油藏深部调剖堵剂体系适应性研究

针对长庆油田吴410区超低渗透、裂缝性油藏,评价了甲叉基聚丙烯酰胺类化学成胶堵剂及体膨凝胶颗粒堵剂对裂缝的封堵性能。甲叉基聚丙烯酰胺类化学成胶堵剂具有地面粘度低(≤34mPa·s,泵注性能好)、成胶时间可控(16～72h,60℃)、堵水选择性好(油相岩心封堵率≤40.7%,水相岩心封堵率≥97.6%;油相岩心突破压力≤0.91MPa/m,水相岩心突破压力≥1.75MPa/m)、封堵率高等特点;体膨凝胶颗粒堵剂具有淡水中膨胀率高、盐水中膨胀率低、膨胀后的凝胶颗粒具有变形通过性能等特点。确定了针对吴410区长6超低渗裂缝性油藏调剖工艺的"前置甲叉基聚丙烯酰胺类化学成胶堵剂+体膨凝胶颗粒堵剂+柔性胶粉堵剂封口"的调剖剂体系及"大剂量、小排量、多段塞、控压力"调剖工艺,并进行了现场工艺试验。统计2012年吴410区3口典型调剖井,平均注水压力上升1.5MPa,至目前,单井组内油井平均增油已超200t,调剖增油效果良好。同时对调剖失败井进行对比总结分析,为以后堵水工艺提供参考意见。

高温低伤害压裂液性能优化与应用

中原油田应用的压裂液存在着残渣含量高、表面活性差、地层损害程度严重等问题。针对深井高温地层压裂改造的要求,采取了降低成胶剂残渣含量、提高液体表面活性、稳定地层粘土矿物、改善交联体系以及实行分段破胶等技术措施,使压裂液具有良好的高温稳定性与地层保护能力。新的压裂液体系主要由低残渣羟丙基胍胶、HY-605和HF-605高活性复合表面活性剂体系、新型油溶性树脂、复合型粘土稳定剂和高温延迟交联剂OB-99组成。高温低伤害压裂液体系在现场3井次应用表明,该压裂液保证了高砂比、大排量和复杂工艺条件下的压裂施工顺利进行,取得了显著的增产效果,压后初期日增油量为51.3 t,累计增油量为4900 t;日增天然气量为8300 m^3,累计增气量为124.5×10~4m^3。

金属交联羧甲基羟丙基纤维素的性质

研究了几种多价金属离子交联的羧甲基羟丙基纤维素(CMHPG)的流变性质以及作为水基压裂液的一些基本性能如热稳定性、滤失量、悬砂能力、破胶水化残渣、与盐的配伍性等。用热分析方法测定了交联产物的玻璃化温度、热分解温度和分解速率。实验研究结果表明,金属交联CMHPC 具备油井压裂液成胶剂所要求的性质。

氧对交联聚合物体系黏度长期稳定性的影响

在45℃、曝氧和缺氧条件下，考察了铬交联、铝交联、有机交联聚合物成胶体系配制后60天内黏度的变化。3种成胶体系中聚合物浓度分别为600、600、2400mg／L，用经净化处理、矿化度4013mg／L、SRB菌容易生长繁殖的采油污水配液。有机交联剂为可生成酚醛树脂的有机物混合物。铬交联成胶体系的黏度在5～10天时达到峰值，此后迅速减小并丧失；曝氧条件下的黏度普遍高于缺氧条件下的相应黏度；加入杀菌剂使曝氧、缺氧条件下的黏度均有所增大。铝交联成胶体系的黏度变化可划分为：维持低而稳定的值（1～20天）、缓慢增大（30～50天）、迅速降低（60天）3个阶段；FR和FRR测定表明在第一阶段聚合物分子线团内部发生交联，第二阶段被认定为聚合物分子线团间发生交联；铝交联成胶体系在曝氧条件下的黏度普遍高于缺氧条件下的黏度；加入杀菌剂使曝氧和缺氧条件下的黏度均增大，并且使第二阶段至少扩展到60天以后。有机交联成胶体系10天时形成强凝胶，曝氧条件下1～5天的黏度值高于缺氧条件下的相应值，加入杀菌剂使曝氧、缺氧条件下的黏度值均有所增大。曝氧和使用杀菌荆可改善污水配制的各种交联聚合物体系黏度的长期稳定性。表6参12。

Nonfoaming Bubble Separation for Recovery of Butyl Acetate from Discharged Wastewater During Penicillin Production

Two nonfoaming bubble separation techniques, air stripping and solvent sublation, are presented and discussed in order to recover butyl acetate (BA) from discharged wastewater after solvent extraction of penicillin. Results show air stripping is not suitable for the recovery of BA from the wastewater. Axial concentration of BA had a noted maximum point along the column. In contrast, solvent sublation is very effective to recover BA from the wastewater. In solvent sublation experiments, axial concentration of BA along the column first increased and then decreased from the bottom to the top because of two primary mass transport processes. One is the transport by adsorption or attachment to ascending bubbles, and the other is by dispersion at water-solvent interface and by water film in organic solvent layer. In order to elucidate the high removal efficiency in solvent sublation, the microstructure of the wastewater was studied with optic microscope, which was showed to be an emulsion of BA in water at large concentration of BA. Solvent sublation can be successfully used in the removal of BA from its emulsion in the wastewater. The surface tension of simulated solution composed of lysozyme and BA was studied to understand mutual effect of biological materials and BA. Results show that lysozyme affects the adsorption of BA at air-water interface and they may form a complex between BA and lysozyme molecules.

Lead Removal from Aqueous Solutions Using Novel Gel Adsorbent Synthesized from Natural Condensed Tannin

Lead has caused serious environmental pollution due to its toxicity, accumulation in food chains and persistence in nature. In this paper, removal of lead from aqueous solutions is investigated using a novel gel adsorbent synthesized from natural condensed tannin. The novel adsorbent performs in aqueous solutions as a weak base with valid basic groups of 1.2mmol·g-1 tannin gel particles and therefore results in the elevation of pH value of aqueous solutions. Even when initial pH is 3.6, final pH at equilibrium can climb up to 6.5 that is above the pH value for Pb(OH)2 precipitation formation and then lead can be removed from wastewater by this so-called surface precipitation. The adsorption isotherm can be expressed by the Langmuir equation and the maximum capacity for adsorption of Pb is up to 92 mg·g-1 (based on dry adsorbent) when initial pH value is 3.6. Hence, the adsorbent does offer favorable properties in lead removal with respect to its high adsorption capacity at low initial pH value, which is advantageous to lead removal from acidic wastewater. A model is put forward to describe the individual adsorption phenomenon of the tannin gel adsorbent.

Herbal compound 861 regulates mRNA expression of collagen synthesis- and degradation-related genes in human hepatic stellate cells

AIM： To identify the role of herbal compound 861 （Cpd 861） in the regulation of mRNA expression of collagen synthesis- and degradation-related genes in human hepatic stellate cells （HSCs）. METHODS： mRNA levels of collagen types I and III, matrix metalloproteinase 1 （MMP-1）, matrix metalloproteinase 2 （MMP-2）, membrane type-1 matrix metalloproteinase （MT1-MMP）, tissue inhibitor of metalloproteinase 1 （TIMP-1）, and transforming growth factor β1 （TGF-β1） in cultured-activated HSCs treated with Cpd 861 or interferon-γ, （IFN-γ,） were determined by real-time PCR. RESULTS： Both Cpd 861 and IFN-γ reduced the mRNA levels of collagen type Ⅲ, MMP-2 and TGF-β1. Moreover, Cpd 861 significantly enhanced the MMP-1 mRNA levels while down-regulated the TIMP-1 mRNA expression, increasing the ratio of MMP-1 to TIMP-1 to （6.3 ＋ 0.3）- fold compared to the control group. CONCLUSION： The anti-fibrosis function of Cpd 861 may be mediated by both decreased interstitial collagen sythesis by inhibiting the transcription of collagen type Ⅲ and TGF-β1 and increased degradation of these collagens by up-regulating MMP-1 and down-regulating TIMP-1 mRNA levels.

Recent Advances in Colloidal Lubricant Detergents

Overbased lubricant detergents are important components in lubricating oil. Recently, a lot of papers about the synthesis mechanism, colloidal structure, acid neutralization and antifrictiorL properties of overbased detergents have been published with the development of experimental techniques, which can help us better understand the process of preparation and application of overbased detergents and propound new strategies for improving various performances of overbased detergents. In the future, the synthesis of environmentally friendly and multi-functional lubricant detergent using biodegradable vegetable oil instead of mineral oil as raw materials will be a primary objective for the colloidal lubricant detergent industry.This paper mainly presents the latest advances in the investigation of colloidal lubricant detergents.

THE FABRICATION OF CARBON AEROGELS BY GELATION IN ISOPROPANOL WITH BASIC CATALYST

A new method for the fabrication of carbon aerogels is reported in this paper. Resorcinol and furfural were gelated in isopropanol with basic catalysts and then dried directly under isopropanol supercritical condition, followed by carbonization under nitrogen atmosphere. The bulk densities of carbon aerogels obtained are in the range of 0.21g/cm3~0.27g/cm3 and the sizes of the interconnected carbon nano-particles are in the range of 20nm^30nm. All of the aerogel samples exhibit high BET surface areas in the range of 730m2/g^900m2/g. The bulk density, micro-pore volume, meso-pore volume and meso-pore diameter can be controlled by gelation conditions such as R/I ratio and R/C ratio.

Synthesis and Gel Properties of Sorbitol Derivative Gelators

1,3:2,4-di-p-methylbenzylidene-D-sorbitol(MDBS)is known to be an efficient sorbitol derivative gelator.Two new sorbitol derivative gelators were designed and synthesized in contrast to MDBS in order to study the gel properties of gelators with different structures.Their gelation behavior to 30 solvents was investigated.It was found that the gelation behavior was related to the molecular structure of gelators.Compared with MDBS,the gelator with more hydroxyl in the molecular structure could gel water and that with more aromatic ring could gel aromatic solvent.The fibrous and three-dimensional network of the gels was obtained by scanning electron microscopy(SEM).Ultraviolet-visible(UV-Vis)spectroscopy revealed thatπ-πinteraction was one of the main driving forces for the formation of gels.Theπ-πstacking of gelation increases with the number of aromatic rings in the molecular structure of gelator.Fourier transform infrared(FT-IR)spectroscopy revealed that the hydrogen bonding was also the main driving force for the formation of gels.The layered structure of the gels was studied by X-ray diffraction(XRD).

Verification of Applicability of the Polyurethane Adhesive Based on Castor Oil in the Manufacture of Glued Laminated Bamboo

The current concern with the environment promotes the development of new technologies for production with use of alternative materials, from renewable resources, and changes in production processes, having as main objective the reduction of environmental impact. One of the alternatives for cleaner production is the use of castor oil derivatives instead of non-renewable sources, such as adhesives based on PVA （polyvinyl acetate）, applied in the manufacturing process of glued laminated bamboo. Based on the versatility of the bamboo laminate and the castor oil, and from the perspective of sustainability, this study aims to contribute to the application of new materials and processes, used in the manufacturing industry, by proposing the use of the polyurethane adhesive based on castor oil for glued laminated bamboo manufacturing, which can later be used in the manufacture of several products. To verify the applicability of the polyurethane adhesive based on castor oil in the glued laminated bamboo manufacture, mechanical tests of traction and shearing of the glue sheet were performed in specimens of the said material, and the results were compared with the Cascorez 2590 and Waterbond adhesives. The results showed that the polyurethane adhesive based on castor oil, in the traction test, has superior performance than the Waterbond adhesive and slightly below than the Cascorez 2590 adhesive, but in the shear test, the polyurethane adhesive based on castor oil presented a slightly inferior performance than the other two adhesives used in the comparison.

The impact of solvent and modifier on ZnO thin-film transistors fabricated by sol-gel process

Techniques for fabricating solution-processed zinc oxide(ZnO)-based thin-film transistors(TFTs)are feasible with solution using various routes.Here,ZnO TFTs were fabricated via sol-gel method using zinc acetate as the starting reagent with different modifiers and solvents.The ZnO thin-film semiconductors with well-controlled,preferential crystal orientation and densely packed ZnO crystals can be prepared with the optimized fabrication conditions,exhibiting excellent field-effect far exceeding those of hydrogenated amorphous silicon(a-Si:H).However,the field-effect characteristics of ZnO TFTs were different for different precursor systems which were constituted by zinc acetate,modifiers and solvents.The co-modification of acetoin and monoethanolamine for the precursor system exhibited higher extent of crystal orientation and field-effect.The maximum mobility of 7.65 cm2V-1s-1 and current on-to-off ratio of^105–106 have been obtained.

Intra-individual comparison of different gadolinium-based contrast agents in the quantitative evaluation of C6 glioma with dynamic contrast-enhanced magnetic resonance imaging

This experiment aimed to compare the ionic （Gadodiamide, Gd-DTPA-BMA） and non-ionic （Gadopentetate dimeglumine, Gd-DTPA） gadolinium-based contrast agents （GBCA） in the quantitative evaluation of C6 glioma with dynamic contrast-enhanced magnetic resonance imaging （DCE-MRI）. A C6 glioma model was established in 12 Wistar rats, and magnetic resonance （MR） scans were performed six days after tumor implantation. Imaging was performed using a 3.0-T MR scanner with a 7-inch handmade circular coil. Pre-contrast T1 mapping and dynamic contrast-enhanced T1WI after a bolus injection （0.2 mL s 1） of GBCA at 0.4 mmol kg-1 were performed. Each rat received two DCE-MRI scans, 24 h apart. The first and second scans were performed using Gd-DTPA-BMA and Gd-DTPA, respectively. Image data were processed using the Patlak model. Both Kns and Vp maps were generated. Tumors were manually segmented on all 3D K and Vp maps. Pixel counts and mean values were recorded for use in a paired t-test. Three radiologists independently performed the tumor segmentation and value calculation. The agreements from different observers were subjective to the intra-class correlation coefficient （ICC）. Readers demonstrated that the pixel counts of tumors in/Crns maps were higher with Gd-DTPA-BMA than with Gd-DTPA （P〈0.001, all readers）. Although the/（r,,s values were higher with Gd-DTPA-BMA than with Gd-DTPA, there was no statistical significance （P〉0.05, all readers）. The pixel counts of tumors in Vp maps, as well as Vp values, showed no obvious difference between the two agents （P〉0.05, all readers）. Excellent interobserver measurement reproducibility and reliability were demonstrated in the ICC tests. The Gd-DTPA-BMA contrast agent had significantly higher pixel counts of glioma in the maps, and an increased tendency for average/Us values, indicating that DCE-MRI with Gd-DTPA-BMA may be more suitable and sensitive for the evaluation of glioma.

Solvent-induced molecular gel formation at room temperature and the preparation of related gel-emulsions

The gelation behaviors of four recently reported amphiphilic cholesteryl derivatives (1, 2, 3 and 4) have been evaluated. It was found that the gel formation process can be controlled by introduction of water at room temperature. Addition of water to an acetone solution of 4 immediately results in the system becoming turbid, and a gel subsequently forms within a few minutes. Interestingly, 4 is a super-gelator for a mixed solvent of acetone and water at room temperature, in particular when their volume ratio is close to 1:1 at which the critical gelation concentration (CGC) is 0.06% (w/v). It was found that the introduction of water favors the formation of gel networks, and the gel possesses smart and reversible thixotropic properties. FTIR and 1H NMR spectroscopy confirmed that hydrogen bonding is one of the main driving forces for the gelation of the solvents. XRD demonstrated that 4 self-assembled into a layered structure within the acetone-water mixed solvent gel. Furthermore, 1 and 2 can be used as excellent stabilizers for gel emulsions of alkanes and water. The maximum of the dispersed phase, water, in one of the gel-emulsions can be as high as 97% (v/v).

In situ forming chitosan-based hydrogel as a lung sealant for biological lung volume reduction

Biological lung volume reduction （BLVR） using lung sealant has received more attention recently as a new non-surgical approach to emphysema treatment. Many tissue sealants have been studied but only a few have been proposed for BLVR. In this work, we prepared in situ forming chitosan-based hydrogels （CSG） using covalent cross-linking of chitosan and genipin in the cooperation of ionic interaction between chitosan and sodium orthophosphate hydrate （Na3PO4.12H20） and characterized by Fourier transform infrared spectroscopy, scanning electron microscopy and rheological methods. CSG showed short gelation time （8 min）, high swelling ratio （〉100 %） and non-toxicity （3T3 mouse fibroblast cell viability 〉80 %） under physiological conditions. The application of lung sealant for BLVR was tested in a Chinese dog and evaluated by chest computed tomography. After 3 weeks of the installation of CSG in bronchopulmonary segment, the gel formation was detected at a localized region of bronchi and the local atelectasis occurred. Our findings indicate that this chitosan-based hydrogel is a promising new candidate for use as a lung sealant for BLVR.