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101.
用于测定钢液低氧含量的双层固体电解质研究 总被引:1,自引:0,他引:1
采用“毛坯浆料法”在ZrO2(9%摩尔含量MgO)管状固体电解质基体表面制备了厚度为1-4μm的ZrO2(10%摩尔含量Y2O3)固体电解质涂层,并分别对此在本实验室和美国LeedsandNorthrup公司进行了钢液低氧含量测试,结果表明:涂层没有破坏基体的抗热震性:氧浓差电池电动势的重现性偏差由原来的±2mV;电动势的绝对值提高10mV左右;而比日本Toray公司的同类产品提高35mV,这说明 相似文献
102.
103.
Matthias Berger Kurt Laumen Manfred P. Schneider 《Journal of the American Oil Chemists' Society》1992,69(10):955-960
Regioisomerically pure 1,3-sn-diacylglycerols are conveniently prepared in high yields (>80%) and in large quantities by enzymatic esterification of glycerol
in the presence of various 1,3-selective lipases(Chromobacterium viscosum, Rhizopus delemar, Rhizomucor miehei) and a variety of different acyl donors like free fatty acids, fatty acid alkyl esters and vinyl esters. All reactions are
carried out in aprotic organic solvents of low water content, namelyn-hexane, diethyl ether or tBuOMe. The creation of an artificial interphase between the solvent-immiscible hydrophilic glycerol
and the hydrophobic reaction media by the adsorption of glycerol onto a solid support prior to use was essential for the success
of these transformations. The effects of reaction conditions and the regioselectivities of the lipases on the product yields
are described in detail. 相似文献
104.
105.
Silvana?Martini Constantin?Bertoli Maria?Lidia?Herrera Ian?Neeson Alejandro?MarangoniEmail author 《Journal of the American Oil Chemists' Society》2005,82(5):305-312
An ultrasonic technique was developed to study the crystallization process of edible fats on-line. A chirp wave was used instead
of the conventional pulser signal, thus achieving a higher signal-to-noise ratio. This enabled measurements to be made in
concentrated systems [≈20% solid fat content (SFC)] through a 8.11-cm thick sample without significant signal loss. Fat samples
were crystallized at 20, 25, and 30°C at a constant agitation rate of 400 rpm for 90 min. The crystallization process was
followed by ultrasonic spectroscopy and a low-resolution pulsed nuclear magnetic resonance spectrometer. Specific relationships
were found between ultrasonic parameters [integrated response, time of flight (TF), and full width half maximum] and SFC.
TF, which is an indirect measurement of the ultrasonic velocity (v), was highly correlated to SFC (r
2>0.9) in a linear fashion (v=2.601 SFC+1433.0). 相似文献
106.
废弃木粉与短切玻璃纤维组合增强聚丙烯的力学性能 总被引:1,自引:0,他引:1
用废弃木粉与短切玻璃纤维作为增强材料,制得了组合增强的聚丙烯复合材料,研究了制备工艺及设备、材料配方及界面改性方法等对材料力学性能的影响。结果表明,用单螺杆挤出机制备组合增强材料,可减少对玻璃纤维的损伤,保持较长的玻璃纤维,有利于其增强作用的发挥;随着玻璃纤维含量的增加,体系的力学性能提高,而木粉含量对材料力学性能的影响与玻璃纤维的含量相关;采用硅烷偶联剂对木粉进行表面处理,在基体中添加接枝极性基团的改性聚丙烯,可改善体系的界面结合,提高力学性能。 相似文献
107.
低粘度高固含量醋酸乙烯-丙烯酸酯共聚乳液胶粘剂的研制 总被引:3,自引:4,他引:3
介绍了一种低粘度、高固体含量的醋酸乙烯-丙烯酸丁酯-丙烯酸异辛酯共聚乳液胶粘剂的合成工艺及性能。该乳液粘度低于2500mPa.s,固体含量≥52%,较低的玻璃化温度和良好的耐水性能,应用于卷烟和防水涂料的生产。 相似文献
108.
We state and analyse one-shot methods in function space for the optimal control of nonlinear partial differential equations (PDEs) that can be formulated in terms of a fixed-point operator. A general convergence theorem is proved by generalizing the previously obtained results in finite dimensions. As application examples we consider two nonlinear elliptic model problems: the stationary solid fuel ignition model and the stationary viscous Burgers equation. For these problems we present a more detailed convergence analysis of the method. The resulting algorithms are computationally implemented in combination with an adaptive mesh refinement strategy, which leads to an improvement in the performance of the one-shot approach. 相似文献
109.
110.
The axial dispersion-sedimentation model is commonly used to describe the axial concentrations of solids in three phase bubble columns at low liquid velocities. When the two parameters of this model, the particle settling velocity and the solids axial dispersion coefficient, are uncoupled by the use of various assumptions, physically unrealistic values of these parameters often result. Direct experimental measurements of solids settling rates in bubbly gas-liquid mixtures were carried out. The measured mean settling velocities decreased slightly with gas flow rate and were equal to or slightly less than the single particle free settling velocity in the liquid alone. Solids axial dispersion coefficients were also obtained from the solids settling rate distribution data, and gave values considerably less than the experimental liquid axial dispersion coefficient. 相似文献