聚羧酸类增稠剂在锦纶/羊毛地毯喷墨印花中的应用

使用自制的聚羧酸类增稠剂与酸性染料配制成色浆,应用在锦纶/羊毛地毯喷墨印花工艺中。对印花锦纶/羊毛地毯的脱糊率、得色量及色牢度等进行测试,并与现用的进口增稠剂进行对比。实验结果表明:自制聚羧酸类增稠剂脱糊率为96.75%,得色量及得色均匀度较好,耐摩擦牢度和耐皂洗牢度均高于4级,可替代工厂现有的进口增稠剂用于锦纶/羊毛地毯喷墨印花工艺。

聚硼硅氧烷剪切增稠凝胶的制备影响因素及其在不同温度下的流变性能研究

聚硼硅氧烷剪切增稠凝胶(Polyborodimethylsiloxanes shear thickening gel,PBS-STG)在防护材料领域具有良好的应用前景,但是关于PBS-STG的制备条件和自然环境下的稳定性研究少有报道。本工作系统研究了原料配比、反应时间、反应温度、二甲基硅油黏度对制备PBS-STG的影响以及不同温度下PBS-STG的流变性。PBS-STG的制备条件:二甲基硅油黏度为350 Pa·s,硼酸和二甲基硅油配比趋近为1∶10(B、Si物质的量比),缓慢升温至240℃,反应时间6 h以上。变温实验结果表明:PBS-STG在-40~40℃均具有剪切增稠特性并且性质稳定,在温度为10℃时具有最佳剪切增稠特性,这对PBS-STG在防护领域的应用具有重要指导意义。

两亲聚合物活化剂对稠油的拆解-聚并作用及其动态调驱机理

采用扫描电镜、黏度计、激光共聚焦显微镜、稳定性分析仪、岩心驱替等手段,考察了两亲聚合物稠油活化剂(简称活化剂)对渤海S3稠油拆解降黏、聚并增阻作用及其动态调剖与驱油机理。结果表明:活化剂在水溶液中能形成含有许多空腔的致密空间网络结构,显示较强的增黏能力;活化剂可将油-水界面张力由37.8 mN/m降低至1.4 mN/m,在油膜上接触角由102°降低至30°,将油的连续相拆解至微米级甚至更小的分散相,在油/水质量比1/1时活化剂对渤海S3稠油的降黏率达91.1%;活化剂溶液-稠油分散体系静置60 min后,油滴发生聚并,其粒径由初始的81μm增大到294μm,体系黏度由73 mPa·s升至226 mPa·s;当聚并后的分散体系/模拟水质量比为1/1时,混合体系降黏率达到95.4%,吸附在油-水界面上的活化剂持续发挥作用。单管岩心模型中,与黏度相似的聚合物相比,活化剂的驱替压力更高,含水率下降漏斗分布更宽,采收率增幅(R_(EO))达到20.4百分点,比聚合物增加了10.6百分点;双管岩心模型中,低浓度低黏度活化剂溶液表现出比聚合物更强的调剖和驱油能力。

海上油田普通稠油聚合物驱效果分级评价研究

根据海上油田开发特点和典型聚合物驱油藏的开发实践,建立包括驱替效率、降水效果和增油效果评价指标等三方面的聚合物驱效果评价指标集;考虑油田在聚合物驱投入、产出过程中经济因素的影响,研究了经济极限吨聚增油量与原油价格的关系,提出以吨聚增油量为基础的效果分级评价方法,并建立相应的各个效果评价指标的四级评价标准。实际油田应用表明,建立的方法可以比较全面地评价海上油田聚合物驱的效果,定性半定量地确定聚合物驱的开发水平,对海上油田聚合物驱的开发具有一定的指导作用。

文东油田特低渗储层酸化增注体系的研究与应用

针对传统酸液体系反应速度快、酸化半径小和酸化有效期短等缺点,结合文东油田实际情况,研制了高温缓速、深部穿透的缓速酸主体酸配方,并优化筛选得到酸化液添加剂配方。岩心流动试验表明,该缓速酸使天然岩心的渗透率由0.26×10^(-3)μm^2提高至0.47×10^(-3)μm^2。与纳米聚硅体系复合制备HS-L/WFS复合降压增注体系,解决注水过程中黏土水化膨胀问题,大幅延长酸化有效期。已成功实施16井次,施工工艺成功率100%,累计增油量1 395.4 t,取得了良好的酸化增注效果。

含水回升后期控制聚合物利用效率下降方法研究

2012年大庆油田工业化聚驱含水回升区块有22个,区块进入含水回升期后,随着聚合物用量增加,吨聚产油、吨聚增油明显降低,同时面临吸入剖面反转,平面上聚驱效果差异大等问题,为"改善开发效果、降低三采成本、提高聚合物驱效率",在6个聚合物驱含水回升后期区块,认真剖析了区块开发动态,总结了含水回升后期控制聚合物利用率下降方法,指导以后聚合物驱区块开发调整工作。

特殊结构增稠剂在水溶性涂料中的性能研究

传统聚酰胺类增稠剂虽然在水溶性涂料体系中有一定的增稠效果,但其使用时需要进行预分散,且其在低温环境下容易析出,给涂料的贮存及使用带来了诸多不便。重点研究了特殊结构聚酰胺类增稠剂在水溶性涂料体系中的增稠效果、对抗流挂性能的影响,以及在铝粉烤漆体系中对铝粉排列的影响等,并简述了此类特殊结构增稠剂的增稠机理和铝粉的排列机理。

念好“六字诀”提振“四种气”汇聚“大流量”——济南报业创新方式掀起学习宣传贯彻党的二十大精神热潮

中国共产党第二十次全国代表大会于10月16日至22日胜利召开,这是在全党全国各族人民迈上全面建设社会主义现代化国家新征程、向第二个百年奋斗目标进军的关键时刻召开的一次十分重要的大会。学习宣传贯彻党的二十大精神,是当前和今后一个时期全党全国的首要政治任务。如何创新方式、助力掀起学习宣传贯彻党的二十大精神的“全民热潮”,是党媒必须扛实的责任、普遍思考并发力探索的一项重要议题。山东济南日报报业集团着力念好“高、稳、新、融、近、拓”六字诀,做好“增喜气、扬正气、聚人气、接地气”文章,在举全集团之力、倾各媒体之能做好党的二十大精神新闻宣传工作的基础上,积极举办《领航》——济南市学习宣传贯彻党的二十大精神巨报展等活动,蹚出了一条“让正能量形成大流量、让主旋律发出最强音”的创新路径,助力济南市掀起深入学习宣传贯彻党的二十大精神的“全民热潮”,让党的二十大精神在泉城大地迅速落地生根。

Compressive performance of innovative reinforced pillars in closed/abandoned mines

Pillar is closely related to the stability and reliability of underground spaces in closed/abandoned mines.The present research introduced a new technique to strengthen square cement mortar columns via fiber-reinforced polymer(FRP)strips to verify the strengthening effect of FRP on pillars.Compared to a fully wrapped FRP jacket,the advantages of FRP strip are cost-effective and easy-to-construct.A series of compression tests as well as theoretical analysis were carried out to explore the mechanical behavior of square cement mortar specimens partially strengthened with FRP strips.The results verified the effectiveness of FRP strips in enhancing the stress and strain of cement mortar.Different from unconfined cement mortar specimens,these FRP-strengthened cement mortar specimens are featured with the double-peaked behaviors,mainly attributed to the stress state transformation from a one-dimensional to a three-dimensional stress state.It also indicated that the enhancement of stress increased with the FRP strip width.Moreover,the brittle-ductile transition ductile failure characteristics were also observed in FRP-confined cement mortar specimens.The ultimate ductility of the cement mortar specimen decreases gradually with the growth of the FRP strip width.The main contribution of this research is to enrich the strengthening techniques for residual pillars.

Durability of concrete beams reinforced with CFRP sheet under wet-dry cycles and loading

The test results of eight concrete beams reinforced with carbon fiber reinforced polymer （CFRP） sheets subjected to an aggressive environment under a sustained load are presented. The beams are 1 700 mm long with a rectangular cross-section of 120- mm width and 200-mm depth. The beams are precracked with a four-point flexural load, bonded CFRP sheets, and placed into wet-dry saline water（ NaCl） either in an unstressed state or loaded to about 30% or 60% of the initial ultimate load. The individual and coupled effects of wet-dry saline water and sustained bending stresses on the long term behaviour of concrete beams reinforced with the CFRP are investigated. The test results show that the coupled action of wet-dry saline water and sustained bending stresses appears to significantly affect the load capacity and the failure mode of beam strengthened with CFRP, mainly due to the degradation of the bond between CFRP and concrete. However, the stiffness is not affected by the coupled action of wet-dry cycles and a sustained load.

Shear Thickening Fluids Based on Additives with Different Concentrations and Molecular Chain Lengths

Shear thickening fluids （STFs） based on additives with different concentrations and molecular chain lengths were investigated. STF samples were prepared with silica and additive dispersed in polyethylene glycol （PEG） 400, where three types of additives with different molecular chain lengths of PEG4000, PEG6000, and PEG10000 were used. For PEG10000, different concentrations, including 0, 1%, 3%, and 5%, were selected to study the influences of additive concentrations. Rheological properties of the samples were measured with a rheometer. The results show that the shear thickening effect was significantly enhanced with the increase of the concentration and the molecular chain length of additives. The mechanism of enhancement was quantitatively explained with the formation of large particles clusters.

In-situ reactive compatibilization of HDPE/GTR blends by dicumyl peroxide and phenolic resin without catalyst

In-situ reactive compatibilization of high-density polyethylene （HDPE）/ground tire rubber （GTR） blends by dicumyl peroxide （DCP） and HY-2045 - a kind of thermoplastic phenolic resin without catalyst was investigated by studying the mor-phology, stress and strain behavior, dynamic mechanical properties and crystallization performance of the blends. Scanning e-lectron microscopy （SEM） results show that there are a lot of fibrous materials distributing in the interface, which connects the dispersed phase with the matrix and obtains better interfacial strength for prominent mechanical properties. The addition of compatibilizers results in the decrease of crystallinity of the blends and the disappearance of an obvious yield phenomenon, which was proved by the differential scanning calorimeter （DSC） test and X-ray diffraction （XRD） characterization Although the crystallinity of the blends decreases,the tensile strength and tensile strain of the blends significantly increases, especially for the HDPE/GTR/DCP/HY-2045 blends, which is possibly attributed to the good compatibility of the blends owing to the in-situ interface crosslinking. In addition, it is found that the compatibilizing HDPE/GTR blends shows a higher tan^ peak temperature and a broaden transition peak for GTR phase.

INTERFACE DAMAGE ANALYSIS OF FIBER REINFORCED COMPOSITES WITH DUCTILE MATRIX

A cohesive zone model is employed to simulate the fiber/matrix interface damage of composites with ductile matrix. The study is carried out to investigate the dependence of the interface damage and the composite tensile strength on the micro parameters of the composite. These parameters contain fiber packing pattern, fiber volume fraction, and the modulus ratio of the fiber to the matrix. The investigation reveals that though the high fiber vo lume fraction, the high fiber′s modulus and the square fiber packing can supply strong reinforcement to the composite, the interface damage is susceptible in these cases. The tensile strength of the composite is dominated by the interface strength when the interface debonding occurs.

Bond strength improvement of GFRP rebars with different rib geometries

Based on the Canadian Standards Association (CSA) criteria,105 pullout specimens were tested to investigate the effect of different rib geometries on bond strength of glass fiber reinforced polymer (GFRP) rebars embedded in concrete. Two kinds of conventional reinforcing rebars were also studied for comparison. Each rebar was embedded in a 150 mm concrete cube,with the embedded length being four times the rebar diameter. The experimental parameters were the rebar type,rebar component,rebar diameter,rebar surface texture,rib height,rib spacing and rib width. Theoretical analysis was also carried out to explain the experimental phenomena and results. The experimental and theoretical results indicated that the bond strength of GFRP rebars was about 13%～35% lower than that of steel rebars. The bond strength and bond-slip behavior of the specially machined rebars varied with the rebar type,rebar diameter,rebar surface texture,rib height,rib spacing and rib width. Using the results,design recom-mendations were made concerning optimum rib geometries of GFRP ribbed rebars with superior bond-slip characteristics,which concluded that the optimal rib spacing of ribbed rebars is the same as the rebar diameter,and that the optimal rib height is 6% of the rebar diameter.

Strengthening reinforced concrete beams using prestressed glass fiber-reinforced polymer-Part I: Experimental study

This work is aimed at studying the strengthening of reinforced concrete (R. C.) beams using prestressed glass fi- ber-reinforced polymer (PGFRP). Carbon fiber-reinforced polymer (CFRP) has recently become popular for use as repair or rehabilitation material for deteriorated R. C. structures, but because CFRP material is very stiff, the difference in CFRP sheet and concrete material properties is not favorable for transferring the prestress from CFRP sheets to R. C. members. Glass fi- ber-reinforced polymer (GFRP) sheets with Modulus of Elasticity quite close to that of concrete was chosen in this study. The load-carrying capacities (ultimate loads) and the deflections of strengthened R. C. beams using GFRP and PGFRP sheets were tested and compared. T- and ⊥-shaped beams were used as the under-strengthened and over-strengthened beams. The GFRP sheets were prestressed to one-half their tensile capacities before being bonded to the T- and ⊥-shaped R. C. beams. The prestressed tension in the PGFRP sheets caused cambers in the R. C. beams without cracks on the tensile faces. The PGFRP sheets also enhanced the load-carrying capacity. The test results indicated that T-shaped beams with GFRP sheets increased in load-carrying capacity by 55% while the same beams with PGFRP sheets could increase load-carrying capacity by 100%. The ⊥-shaped beams with GFRP sheets could increase load-carrying capacity by 97% while the same beams with PGFRP sheets could increase the loading-carrying capacity by 117%. Under the same external loads, beams with GFRP sheets underwent larger deflections than beams with PGFRP sheets. While GFRP sheets strengthen R. C. beams, PGFRP sheets decrease the beams’ ductility, especially for the over-strengthened beams (⊥-shaped beams).

Modified imperialist competitive algorithm-based neural network to determine shear strength of concrete beams reinforced with FRP

Fiber reinforced polymers (FRPs), unlike steel, are corrosion-resistant and therefore are of interest;however, their use is hindered because their brittle shear is formulated in most specifications using limited data available at the time. We aimed to predict the shear strength of concrete beams reinforced with FRP bars and without stirrups by compiling a relatively large database of 198 previously published test results (available in appendix). To model shear strength, an artificial neural network was trained by an ensemble of Levenberg-Marquardt and imperialist competitive algorithms. The results suggested superior accuracy of model compared to equations available in specifications and literature.

Thermal-mechanical properties of short carbon fiber reinforced geopolymer matrix composites subjected to thermal load

Short carbon fiber preform reinforced geopolymer composites containing different contents of α-Al2O3 filler （Cr（a-Al2O3）/geopolymer composites） were fabricated, and the effects of heat treatment temperatures up to 1 200 ℃ on the thermal-mechanical properties were studied. The results show that the thermal shrinkage in the direction perpendicular to the lamination of the composites gradually increases with the increase of the heat treatment temperatures from room temperature （25 ℃ ） to 1000 ℃. However, the composites in the direction parallel to the lamination show an expansion behavior. Beyond 1 000℃, in the two directions the composites exhibit a larger degree of shrinkage due to the densification and crystallization. The mechanical properties of the composites show the minimum values in the temperature range from 600 to 800 ℃ as the hydration water of geopolymer matrix is lost. The addition of α-Al2O3 particle filler into the composites clearly increases the onset crystalline temperature of leucite （KAlSi2O6） from the amorphous geopolymer matrix. In addition, the addition of α-Al2O3 particles into the composites can not only help to keep volume stable at high temperatures but also effectively improve the mechanical properties of the composites subjected to thermal load to a certain extent. The main toughening mechanisms of the composites subjected to thermal load are attributed to fiber pulling-out.

Experimental study on bond behavior between BFRP bars and seawater sea-sand concrete

Combining fiber reinforced polymer(FRP)with seawater sea-sand concrete(SSC)can solve the shortage of river sand that will be used for marine engineering construction.The bond performance of BFRP bars and SSC specimens is researched by pull-out test in this paper.The effects of the parameters,such as bar type,bar diameter,concrete type and stirrup restraint,are considered.It is beneficial to the bonding performance by the reduction of bar diameter.The utilization of seawater sea-sand has a low influence on the bond properties of concrete.The bond strength of BFRP is slightly lower than the steel rebar,but the difference is relatively small.The failure mode of the specimen can be changed and the interfacial bond stress can be improved by stirrups restraint.The bond-slip curves of BFRP ribbed rebar include micro slip stage,slip stage,descent stage and residual stage.The bond stress shows the cycle attenuation pattern of sine in the residual stage.In addition,the bond-slip model of BFRP and SSC is obtained according to the experimental results and related literature,while the predicted curve is also consistent well with the measured curve.

“Cutting effect” of organoclay platelets in compatibilizing immiscible polypropylene/polystyrene blends

In this work, polypropylene (PP)/polystyrene (PS) blends with different organoclay concentrations were prepared via melt compounding. Differing from the results of previous reports, the organoclay platelets are mostly located in the dispersed PS phase instead of the interface. The dimensions of the dispersed PS droplets are greatly reduced and apparent compatibilization effect still exists, which cannot be explained by the traditional compatibilization mechanism. A novel compatibilization mecha- nism, "cutting" to apparently compatibilize the immiscible PP/PS blends was proposed. The organoclay platelets tend to form a special "knife-like structure" in the PS domain under the shear stress of the continuous PP phase during compounding. The "clay knife" can split the dispersed PS domain apart and lead to the dramatic reduction of the dispersed domain size.