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排序方式: 共有44条查询结果,搜索用时 31 毫秒
1.
In order to find efficient cold flow improvers for diesel fuels, a series of copolymers (C14MC-MCNR2) derivated from long chain alkyl (i.e., tetradecyl) methacrylate C14MC and methacrylamide (MCNR2) were prepared, and a series of terpolymers (C14MC-MA-MCNR2) derivated from tetradecyl methacrylate C14MC, maleic anhydride (MA), and methacrylamide (MCNR2) were also prepared. These copolymers and terpolymers were purified, and their structures were characterized by IR, 1HNMR, and GPC. Their low temperature fluidities and filterability, such as solid point depression (ΔSP) and cold filter plugging point depression (ΔCFPP), used as cold flow improvers in two diesel fuels were evaluated. The results indicate that: (1) The C14MC-MCNR2 copolymers possess good solid point depressing performance. (2) The C14MC-MA-MCNR2 terpolymers exhibit dual function both as wax dispersants and flow improvers simultaneously, and they all possess very excellent solid point depressing performance, and can attain optimum effectiveness of CFPP depression when NR2 is morpholine.  相似文献   
2.
通过响应面法的Box-behnken试验设计方法构建二次多项式回归方程,对氯乙烯、乙烯和乙烯醚三元聚合物砂浆配合比进行优化,并结合宏观性能与微观形貌进行机理分析.结果 表明:所建模型在试验范围内能较准确地预测结果,响应面法用于三元聚合物砂浆配合比优化具有准确性与科学性;对28 d抗压强度影响强弱顺序依次为水灰比、减水剂掺量、聚合物掺量;对28 d抗折强度和黏结强度影响强弱顺序为聚合物掺量、水灰比、减水剂掺量;将28 d黏结强度最大值、抗折强度最大值和抗压强度最小值(折压比最大)作为目标优化值,得出三元聚合物砂浆的最优配合比为:聚合物掺量为12%,水灰比为0.42,减水剂掺量为1.12%.  相似文献   
3.
AM/AA/DMDAAC三元共聚物的合成及其在泥浆中的性能   总被引:5,自引:1,他引:4  
在室内合成了AM/AA/DMDAAC三元共聚物,考察了合成因素对共聚物作为泥浆处理剂的性能的影响,对所得共聚物作了初步的室内性能评阶,结果表明它具有显著的降虑失作用和较好的防塌效果。  相似文献   
4.
Optimal control policies for emulsion terpolymerisation of styrene, methyl methacrylate (MMA) and methyl acrylate (MA) were determined in a semi-batch reactor using the multi-objective dynamic optimisation method. A comprehensive dynamic model was used for the design of optimal control. The control vector parameterisation (CVP) approach was implemented for constrained optimisation for emulsion terpolymerisation reactors. The feed rates of styrene, MMA, MA, surfactant and initiator, and the temperature of the reactor were used as manipulating variables to produce terpolymers of desired composition, molecular weight distribution (MWD) and particle size distribution (PSD). The particle size polydispersity index (PSPI), molecular weight polydispersity index (MWPI) and the overall terpolymer composition ratios were incorporated in the objective functions to optimise the PSD, MWD and terpolymer composition, respectively. The optimised operational policies were validated with experiments via one stirred tank polymerisation reactor.  相似文献   
5.
采用MM-2000型摩擦磨损试验机评价了PA/TLCP二元共混物的摩擦学性能;同时考察了马来酸酐接枝三元乙丙共聚物对PA/TLCP二元共混物摩擦学性能的影响.分析测试结果表明:引入马来酸酐接枝三元乙丙共聚物为相容剂能够有效地提高界面增容作用,材料力学性能提高;同时,相容剂的加入,改善TLCP与基体PA66的结合强度,提高了共混物的耐磨性,也有利于转移膜的形成.  相似文献   
6.
采用本体聚合的方法,以苯乙烯、丙烯腈、马来酸酐为反应单体,加入引发剂、链转移剂合成了苯乙烯-丙烯腈-马来酸酐(SAM)三元共聚物.研究了引发剂种类、用量及链转移剂用量对三元共聚物摩尔质量的影响,寻求最优的合成条件;并以自制的SAM来增容聚碳酸酯(PC)/丙烯腈-丁二烯-苯乙烯(ABS)共混物,探讨了SAM对共混物性能的影响.通过红外(FTIR)、核磁(1H-NMR)、差示扫描量热仪(DSC)对三元聚合物结构进行了分析.研究表明:引发剂偶氮二异丁腈(AIBN)效果优于过氧化苯甲酰(BPO),苯乙烯、丙烯腈、马来酸酐物质的量之比为60:38:2,链转移剂十二硫醇(TDM)和引发剂偶氮二异丁腈(AIBN)的用量均为单体总质量的0.1%时,可获得摩尔质量为80 000g/mol左右的三元共聚物SAM;SAM对PC/ABS共混物起到了增容作用.  相似文献   
7.
Abstract

In order to find efficient cold flow improvers for diesel fuels, a series of copolymers (C14MC-MCNR2) derivated from long chain alkyl (i.e., tetradecyl) methacrylate C14MC and methacrylamide (MCNR2) were prepared, and a series of terpolymers (C14MC-MA-MCNR2) derivated from tetradecyl methacrylate C14MC, maleic anhydride (MA), and methacrylamide (MCNR2) were also prepared. These copolymers and terpolymers were purified, and their structures were characterized by IR, 1HNMR, and GPC. Their low temperature fluidities and filterability, such as solid point depression (ΔSP) and cold filter plugging point depression (ΔCFPP), used as cold flow improvers in two diesel fuels were evaluated. The results indicate that: (1) The C14MC-MCNR2 copolymers possess good solid point depressing performance. (2) The C14MC-MA-MCNR2 terpolymers exhibit dual function both as wax dispersants and flow improvers simultaneously, and they all possess very excellent solid point depressing performance, and can attain optimum effectiveness of CFPP depression when NR2 is morpholine.  相似文献   
8.
大庆油田聚合物驱采出水配制的聚合物溶液驱油效果研究   总被引:4,自引:0,他引:4  
卢祥国  高振环 《油田化学》1996,13(4):361-363
收集了大庆油田北一区断西聚合物驱工业试验区采出水,用于配制聚合物溶液并在非均质人造油层物理模型上进行了驱油试验,其结果表明采出水直接回注或用于配制聚合物驱油溶液都是可行的  相似文献   
9.
A novel chelating resin was synthesized and characterized by elemental, physico-chemical, GPC, NMR, and SEM analyses. Batch separation was adopted to study the recovery of selected metal ions with respect to the pH, time, concentrations, and electrolytes. From the results, it was observed that the order of the rate of metal ion uptake by the resin was Fe3+ > Cu2+ > Zn2+ > Ni2+ > Co2+ > Pb2+ ions. The adsorption kinetics follows first order, and isotherm models were also found to fit each other. The resin showed three-step thermal degradation, and its kinetic and thermodynamic parameters were also evaluated.  相似文献   
10.
The nonisothermal crystallization kinetics of a polyolefin terpolymer (poly(propylene-co-ethylene-co-1-butene) and its expanded foam was investigated by differential scanning calorimetry. A kinetic equation for nonisothermal crystallization was employed to analyze the crystallization characteristics of the terpolymer and its foam. The Avrami exponent, n, can be reasonably well determined from the nonisothermal crystallization exotherm. The polarized optical microscopy showed that pristine terpolymer had a well-developed spherulite morphology whereas the foamed terpolymer consisted of elongated entities that subsequently developed as more bundle-like entities. The latter morphology is typical one of the γ phase. The difference in crystallization behavior observed for the pristine and foamed terpolymer samples is attributed to the formation of different morphologies during the foam expansion process.  相似文献   
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