Expansion Performance and Microstructure of High-performance Concrete using Differently Scaled MgO Agents and Mineral Powder

To investigate the assumptions proposed in this paper,the evolution law governing the strength and expansion performance of MgO and nano-MgO micro-expansive concrete in the environment of mineral powder was firstly observed in this study.Secondly,SEM,XRD,and TG-DSC microscopic tests were conducted to reveal the effects of the active mineral-powder admixture on the hydration degree and expansion performance of MgO and nano-MgO in HPC.Our experimental results successfully verified our hypothesis,which indicated that the expansion performance of macro-MgO and nano-MgO was indeed depressed by the addition of active mineral power admixtures,even though the mechanical property of concrete composites was effectively improved.Furthermore,the hydration test also demonstrated the negative interference on the mineral powders,which was induced by the expansion agents.It is found the amounts of hydrates tend to decrease because the mineral powder ratio reaches and exceeds 40%.Moreover,it is also concluded the effect of expansion agents is governed by the alkalinity cement paste,especially for the nano-MgO.In other words,the expansion performance of nano-MgO will vary more obviously with the hydration process,than MgO.The results of this study provide that effective experimental and theoretical data support the hydration-inhibition mechanism of magnesium expansive agents.

EFFECT OF SILANE ON THE SURFACE OF SEALING GLASS

This paper, through XPS and IR analyses on the surface of sealing glass, identifies that the surface treatment of sealing glass by silane is a chemical process. On the basis of the analyses, the authors suggest an ideal chemical bonding status between silane and glass surface.

Seal & Protect封闭剂治疗牙本质过敏症的疗效评价

目的 观察Seal＆Protect封闭剂治疗牙本质过敏症的作用,通过扫描电镜观察Seal＆Protect封闭人离体牙牙本质小管的效果。方法 牙本质过敏患牙180颗,实验组90颗,用Seal＆Protect治疗,对照组90颗用30％草酸钾治疗。取离体牙30颗,于颈部制备洞型,分3组(第1组涂布Seal＆Protect,第2组涂布30％草酸钾,第3组未经任何处理作空白对照)扫描电镜观察表面形态。结果 实验组治疗后的即刻疼痛缓解有效率100％,3个月复查有效率97.78％,而用30％草酸钾即刻疼痛缓解有效率为96.67％,3个月复查有效率87.78％,两者有显著差异(P<0.05)。SEM观察显示经Seal＆Protect和草酸钾处理,大部分牙本质小管被封闭。结论 Seal＆Protect能有效地封闭牙本质小管,是一种有效的治疗牙本质过敏症的脱敏剂。

SEAL-80型透水混凝土抗堵塞性能提升试验研究

为提升透水混凝土的抗堵塞性能,在对人行道堵塞物分析的基础上,采用室内材料试验方法将性能优异的SEAL-80憎水剂内掺于透水混凝土中,然后对SEAL-80型透水混凝土进行抗压强度试验、有效孔隙率试验以及堵塞试验,综合评价SEAL-80型透水混凝土的抗堵塞性能。试验结果表明:在透水混凝土加入SEAL-80憎水剂可以有效提升其抗堵塞性能;SEAL-80憎水剂的最佳推荐掺量为干态用量的0.2%。

双端硅改性SSBR合成及其在胎面胶中的应用研究

通过以自合成的硅锂为引发剂,二乙烯基苯DVB为偶联剂,氯代硅烷为封端剂合成双端含有硅烷改性的溶聚丁苯橡胶,并研究其性能特点。结果表明,自合成的官能化硅锂引发剂,可以稳定获得90%以上收率,储存稳定性好、活性高;合成的双端含有硅改性的SSBR,与以n-BuLi为引发剂的SSBR性能对比,耐磨性提高6.5%,压缩生热降低4℃,滚动阻力降低21.5%,体现出优异的燃油经济性。

改性硅溶胶封孔剂对多孔Al_(2)O_(3)陶瓷绝缘性能和微观结构的影响

采用甲基三甲氧基硅烷和二甲基二甲氧基硅烷对硅溶胶进行改性制得有机硅改性硅溶胶封孔剂,并通过浸渍和加热固化的方法对多孔Al_(2)O_(3)陶瓷片进行封孔处理。研究了固化温度和固化时间对封孔Al_(2)O_(3)陶瓷片绝缘性能的影响,并对多孔Al_(2)O_(3)陶瓷片封孔前后的微观结构进行了表征。结果表明,较佳封孔条件为固化温度120℃、固化时间60 min,此时封孔Al_(2)O_(3)陶瓷片的直流和交流击穿电压分别达到最大值10.76 kV和6.01 kV,1000 V绝缘电阻不低于9999 MΩ。封孔Al_(2)O_(3)陶瓷片表面为改性硅溶胶涂层,呈致密无孔隙状态且与基体结合紧密,涂层厚度约为25μm,表面水接触角提高到86.93°,封孔层深度约为10μm。

塔河耐温抗盐凝胶堵剂的制备及性能评价

以两种类型的聚丙烯酰胺(Q-9、Q-7)为主剂,刺槐豆胶作为增强剂,硫脲作为除氧剂,对苯二酚、乌洛托品作为交联剂,制备了一种具有耐温抗盐的凝胶堵剂;以基液黏度、成胶时间、成胶强度和脱水量为依据优选最佳配方,考察了该凝胶堵剂的成胶强度、耐温性能和封堵效果。结果表明,最佳配方1%聚合物Q-9+0.5%聚合物Q-7+0.3%刺槐豆胶+0.25%硫脲+0.6%乌洛托品+0.6%对苯二酚,基液黏度为854.4 mPa·s,在130℃条件下,成胶时间3.4 h,成胶强度34~37 Pa, 30 d内脱水量为0.443 9 mL;注入1 PV凝胶基液时,突破压力达36 MPa,封堵率为99.63%。

水基钻井液复合纳米成膜封堵剂的制备及性能

以改性纳米SiO_(2)为刚性粒子,丙烯酰胺、2-丙烯酰胺基-2-甲基丙磺酸、苯乙烯和醋酸乙烯酯为聚合单体,壬基酚聚氧乙烯醚(10)和十二烷基磺酸钠为乳化剂,过硫酸铵和亚硫酸氢钠为引发剂,合成了一种有机/无机复合纳米成膜封堵剂。采用FTIR、SEM、动态光散射(DLS)和TGA对产物进行了表征和测试。考察了不同质量分数复合纳米成膜封堵剂对水基钻井液的流变性、滤失性及封堵性能的影响。结果表明,复合纳米成膜封堵剂呈球形,并保持纳米级分布,中值粒径为325 nm;340℃时的质量损失率为14%;120℃、16 h老化后较老化前表观黏度和塑性黏度均明显增加。当复合纳米成膜封堵剂质量分数为3%时,水基钻井液的静滤失量为10 mL;当质量分数≥2%后,砂床滤失量为0;当质量分数从0增至4%时,高温高压滤失量从104 mL减至29 mL,渗透性为1.56×10^(–2)mD,封堵率为90.7%。

Evaluation of the injection and plugging ability of a novel epoxy resin in cement cracks

Sustained casing pressure(SCP)is a crucial issue in the oil and gas production lifecycle.Epoxy resins,exhibiting exceptional compressive strength,ductility,and shear bonding strength,have the potential to form reliable barriers.The injectivity and sealing capacity of the epoxy resin is crucial parameters for the success of shallow remediation operations.This study aimed to develop and assess a novel solid-free resin sealant as an alternative to Portland cement for mitigating fluid leakage.The investigation evaluated the viscosity,compressive strength,and brittleness index of the epoxy resin sealant,as well as its tangential and normal shear strengths in conjunction with casing steel.The flow characteristics and sealing abilities of conventional cement and epoxy resin were comparatively analyzed in cracks.The results showed that the application of a viscosity reducer facilitated control over the curing time of the epoxy resin,ranging from 1.5 to 6 h,and reduced the initial viscosity from 865.53 to 118.71 m Pa,s.The mechanical properties of the epoxy resin initially increased with a rise in curing agent content before experiencing a minor decrease.The epoxy resin containing 30%curing agent exhibited optimal mechanical properties.After a 14-day curing period,the epoxy resin's compressive strength reached81.37 MPa,2.12 times higher than that of cement,whereas the elastic modulus of cement was 2.99 times greater than that of the epoxy resin.The brittleness index of epoxy resin is only 3.42,demonstrating high flexibility and toughness.The tangential and normal shear strengths of the epoxy resin exceeded those of cement by 3.17 and 2.82 times,respectively.In a 0.5 mm-wide crack,the injection pressure of the epoxy resin remained below 0.075 MPa,indicating superior injection and flow capabilities.Conversely,the injection pressure of cement surged dramatically to 2.61 MPa within 5 min.The breakthrough pressure of0.5 PV epoxy resin reached 7.53 MPa,decreasing the crack's permeability to 0.02 D,a mere 9.49%of the permeability observed following cement plugging.Upon sealing a 2 mm-wide crack using epoxy resin,the maximum breakthrough pressure attained 5.47 MPa,3.48 times of cement.These results suggest that epoxy resin sealant can be employed safely and effectively to seal cracks in the cement.

码垛和拆垛机器人在封尘剂智能加药系统中的应用

目前选煤厂固化封尘剂智能加药过程自动化程度低,码垛与拆垛过程需要大量的人工参与,人工效率低,容易出现错误,直接关系选煤厂的经济效益。介绍了码垛拆垛机器人技术原理与系统架构,将先进的自动码垛与拆垛技术引进固化封尘剂智能加药系统,研发的自动码垛和拆垛系统包含:胶带输送单元、振平单元、机器人及地轨单元、滚筒输送单元、拆包称重单元和废袋收集单元,为选煤厂固化封尘剂智能加药系统提供了一种全自动技术方案。

金属防腐用高分子封闭涂层的制备及性能

[目的]提出一种操作简单、防腐效率高、耐摩擦性能强的金属表面防腐涂层的制备方法。[方法]以环氧树脂、氨乙基氨丙基三甲氧基硅烷、微米级纤维素颗粒、纳米级二氧化硅颗粒、正硅酸四乙酯、丙烯酸六氟丁酯等原料制备了一种封闭剂,采用空气喷涂法在铜基体上得到封闭涂层。[结果]丙烯酸六氟丁酯单体和修饰剂三氟丙醇的引入使涂层拥有较低表面能的同时又具有优异的粘附性。涂有封闭剂的铜片经历6000 h的盐雾试验后质量仅减少了7.4%左右,在王水中被完全腐蚀掉的时间比空白铜片延后了至少350 min。[结论]该封闭涂层具有优异的耐腐蚀和耐摩擦性能。

页岩储层的高性能水基钻井液体系分析

页岩储层黏土矿物含量高,易发生水化膨胀、分散现象,造成钻井施工井壁高摩阻使卡钻事故频发。因此,针对性地优选钻井液用抑制剂、封堵剂、润滑剂等关键处理剂,优化出适合X区块页岩储层钻井施工技术难点的高性能水基钻井液体系质量分数:3%土浆、2%JS-2a、2%NBG-2、3%FCZ、5%ZN、1%G1140、1%KPS-1、1%KPS-2、7%KCl、重晶石等组合。结果表明:该体系可有效维持页岩储层井壁稳定,具有良好的润滑作用,较好地解决钻井过程中的井壁失稳和易卡钻等问题,缩短了钻井周期。优化后的页岩储层的高性能水基钻井液体系具有良好的抑制性、疏水性,极压润滑系数由0.112下降至0.082,接触角范围从26.00°增加到93.95°,抗温能力由100℃提高至120℃,密度由1.5 g·cm^(-3)提高至1.8 g·cm^(-3),具有较好的推广应用前景。

一种油气田用耐高温凝胶调堵剂制备及性能研究

为解决油气田开发中的油田水淹、低渗透区出油率低等问题,试验以稻壳灰为主要材料,结合表面活性剂,制备一种耐高温凝胶调堵剂,并对其性能和应用效果进行研究。结果表明,当A剂中含有8%稻壳灰粉末和8%表面活性剂,B剂(表面活性剂)浓度为1%时,配制的凝胶调堵剂耐盐性、耐高温性良好,呈碱性。其中,当凝胶调堵剂中的水溶液为10×104 mg/L矿化度盐水时,成胶率达到72%。该凝胶调堵剂在100℃温度下保温100 d时,凝胶黏度达到74.3 MPa·s。另外,该凝胶调堵剂在空气渗透率为1000~8000 mD时,人造岩心的封堵率达到91%以上,封堵性能良好。

封端型水性聚氨酯固化剂的合成及应用

封端型水性聚氨酯固化剂是现阶段汽车工业的重要研究内容,其在汽车滤纸中的应用,能够有效提高滤纸的硬挺度和耐水性。基于此,文章研究了以甲苯二异氰酸酯、聚丙二醇作为反应原料,NaHSO_(3)作为封端剂,结合乳化剂的使用所制备成的新型封端型水性聚氨酯固化剂,凭借其简单的合成方法和低成本优势,提高滤纸品质。

福山油田绳结暂堵转向压裂工艺

海南福山油田储层主要特点薄互层发育,油层厚度小,隔层泥质含量高,使用可溶球和颗粒暂堵剂实现层间暂堵转向,存在暂堵压力响应不明显,颗粒暂堵剂堵塞压裂泵车柱塞阀的问题。通过对暂堵材料、暂堵工艺的改进,使用新型绳结暂堵球,取代了以往的可溶球和颗粒暂堵剂;同时在室内开展了薄互层射孔优化、携砂液对孔眼冲蚀规律分析、绳结暂堵球直径大小和数量与射孔孔眼的匹配研究,形成了适应福山油田储层特征的绳结暂堵转向压裂工艺。经福山油田应用17口井27层,暂堵转向有效率82%,单井平均日增油4.28 t/d,取得较好增产效果。该工艺进一步提高了薄互层压裂改造效率,具有良好的推广应用价值。

钻井液用封堵剂的评价方法及影响因素

井塌、井漏、油气层保护是当前制约钻井工程顺利进行的3大技术难题。为了解决此难题,要求钻井液具有强的封堵性能。通过对钻井液封堵剂的评价方法及影响因素进行研讨,提出采用42型或71型高温高压滤失量测定仪,测定钻井液HTHP滤失量、HTHP渗透失水、HTHP砂床滤失量和HTHP砂床渗透失水4个指标来评价钻井液的封堵效果;并对钻井液封堵剂种类、加量、膨润土和加重剂含量、钻井液中固相粒级分布、含油量、温度、压差、地层裂隙大小等因素对钻井液封堵效果的影响进行了研讨。得出,复配使用降滤失剂、沥青类产品、成膜封堵剂等可以有效实现对地层裂隙的封堵,随温度与压差增加,封堵剂的品种与加量必须进行调整。

水基钻井液用防塌封堵剂封堵效果实验研究

采用高温高压静失水评价方法,开展了沥青类封堵剂、刚性颗粒封堵剂以及其它封堵剂等单剂的评价与优选,并开展了复配封堵剂优化的实验。结果表明,乳化沥青在沥青类封堵剂中封堵效果最优,超细碳酸钙(1 000目)在刚性颗粒封堵剂中封堵效果最优,乳化石蜡在其它封堵剂中封堵效果最优。在常用封堵剂的组合中,3%超细碳酸钙(1 000目)+2%乳化沥青为水基钻井液用最佳封堵配方。

改性淀粉-丙烯酰胺接枝共聚调堵剂的动态成胶性能

深部封堵技术是改善窜流型油藏开发效果的关键技术之一。改性淀粉-丙烯酰胺接枝共聚体系是新型的聚合物凝胶调堵剂。采用30m超长填砂管,模拟了吉林扶余油田的基质和高渗透条带,研究了这种调堵剂在油藏运移过程中的动态成胶性能。研究结果表明,该调堵剂在运移过程中仍能形成凝胶,其初始成胶时间与在静态条件下基本相同,但完全成胶时间比在静态条件下长;调堵剂完全成胶后,具有很强的封堵能力,封堵系数高达30000。

低密度膨胀型堵漏技术在塔深1井的应用

塔深1井设计井深为8000m,在同一裸眼井段中存在多套压力系统,易发生井漏、井涌;而且地层特殊,存在地下水,纵向及横向裂缝交错,大小溶洞直径差别大,非均质性严重,漏失通道存在着进口小、出口大的裂缝形态,增加了堵漏施工难度。采用低密度膨胀型堵漏浆在塔深1井6237~6650m井段进行了堵漏,并分为两段进行。第一段为潜在漏失段(6650~6350m),采用低稠化度堵漏浆。第二段为确定的严重漏失段(6350~6235m),采取中稠化度堵漏浆,其配方为:5m3井浆+25m3井场水+(0.5%~2%)密度调节剂SD-D+(2%~3%)低密度油层保护剂SD-A+(1%~2%)流型调节剂SD-R+(1%~2%)低密度提粘剂SD-V+(1%~2%)高效提粘剂SD-HV+(1%~2%)填充加固剂MF-1+(5%~6%)填充加固剂MF-2+(60%~80%)悬浮稳定剂SF-1+(1%~2%)棉子皮+(2%~3%)锯末+(3%~4%)云母。该堵漏技术取得了理想的堵漏效果,实现了一次固井。