Measurement of minimum angle of resolution (MAR) in the stereoscopic display using the optotype of stereoscopic stimuli

In stereoscopic images, the crossing point of the viewing directions of the two eyes determines the perceived depth. Assuming that accommodation is affected by the positions of the crossing point, the effect of crossing point on minimum angle of resolution (MAR) was investigated. For 40 participants, MAR was measured by two‐alternative forced choice where Snellen optotype E of up and down directions were used as two kinds of stimuli. As the crossing point of the viewing direction of the left and right eyes moves farther from the sample display, the ability to identify the direction of letter E decreases at the optotype of the same line thickness. The change of MAR shows linear trends with respect to the optical power change that are the reciprocal of the distance from the participant to the crossing points located out of screen and on screen.     

Moisture adsorption characteristics of a thin bed of polycrystalline potash pellets: Part I. Experimental study

This study is an experimental investigation of heat and moisture transfer within a packed bed of polycrystalline, porous potash pellets. Experiments were first performed to determine the moisture uptake characteristics on individual pellets subject to a step-change in relative humidity. Then a bed of pellets was subjected to flows of humid air on the upper boundary and a cold impermeable surface on the lower boundary resulting in a temperature gradient across the bed. Temperature and moisture content were measured within the bed. It was found that moisture uptake is less for potash pellets and they are less likely to cake than granular and standard potash when subjected to the same ambient air conditions. This is due to the porous nature of the pellet and its nearly uniform size and spherical shape.     

Preparation and properties of magnetorheological elastomers based on silicon rubber/polystyrene blend matrix

Magnetorheological (MR) elastomers, which are mainly composed of magnetic particles and elastic polymer, are a new kind of smart materials whose modulus can be controlled by changing the strength of magnetic fields. In this article, MR elastomers based on immiscible silicon rubber/polystyrene (SR/PS) blend matrix were fabricated successfully via cosolvent method and the MR effect, electric and mechanical properties, and the microstructures of the corresponding materials were studied. SEM studies showed that the dispersion of iron particles in blend matrix were different from that in single polymer, which could be further proved by the different electric conductivity. The MR effect of MR elastomers based on blend matrix varied with the different ratios of SR and PS, which was discussed in detail from the special dispersion of iron particles and of zero‐modulus of MR elastomers. In addition, the MR elastomers based on SR/PS blend matrix had enhanced mechanical properties, which made them more hopeful to be applied in practice. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 103: 3143–3149, 2007     

Injectable hydrogels of poly(?-caprolactone-co-glycolide)-poly(ethylene glycol)-poly(?-caprolactone-co-glycolide) triblock copolymer aqueous solutions

Thermogelling triblock copolymers of poly(?-caprolactone-co-glycolide)-poly(ethylene glycol)-poly(?-caprolactone-co-glycolide) [P(CL-GA)-PEG-P(CL-GA)] were successfully prepared by control of the hydrophilicity/hydrophobicity balance and chemical compositions of the copolymers. The aqueous solutions of the copolymers underwent sol-gel transition as the temperature was increased from 20 to 60 °C. The amphiphilic copolymer formed micelles in water and a gel was formed by aggregation of micelles. The structure parameters played a critical role in determining sol-gel transition behavior. Either increasing [GA]/[CL] ratio or decreasing P(CL-GA) block length could induce the increase of the lower sol-gel transition temperature. Glycolide (GA) was incorporated into the polymer chain to increase the polymer degradation rate. Sustained release of rifampicin for approximately 32 days was obtained from the gel. It is believed to have potential applications in drug delivery and tissue engineering.     

超支化含苯基聚硅氧烷亲二氧化碳特性及其分子模拟

通过水解缩聚法制备含有不同苯基含量的超支化聚硅氧烷，探究苯基的引入对超支化聚合物在CO2中溶解性能的影响。浊点压力测试得出苯基的引入在超支化结构中对聚合物在CO2中的溶解度影响不大，超支化聚合物中苯基含量的增加没有导致浊点压力的明显升高，有望实现作为CO2增稠剂兼具较好的溶解度和增稠性能。分子模拟计算分析了超支化聚硅氧烷和直链聚硅氧烷与CO2分子间的相互作用以及超支化聚硅氧烷分子间的相互作用，发现含苯基的超支化聚硅氧烷具有更低的内聚能密度（CED）和溶解度参数（δ），表现出更弱的聚合物分子间相互作用，有利于超支化有机硅氧烷在CO2体系中的溶解。     

高吸水性树脂与PVC共混的研究

用高吸水性树脂与PVC共混制备了吸水膨胀性PVC共混物。实验证明,部分水解丙烯酸甲酯—醋酸乙烯酯HP(MA—VAC)和丙烯酸甲酯—醋酸乙烯酯—甲基丙烯酸甲酯HP(MA—VAC—MMA)共聚物与PVC共混效果更好。研究了影响共混物吸水率和力学性质的各种因素。结果表明,随高吸水性树脂用量增加,共混物吸水率显著增加。当吸水树脂用量大于40%时,共混物的拉伸强度和断裂仲长率下降。共混物最大吸水率达22.17克水/克共混物,最大膨胀度为15倍。     

积层多层板用UV油墨的合成研究

采用丙烯酸改性环氧树脂E－44的方法，合成了环氧丙烯酸酯预聚物，并将其用在UV光固化油墨的配方中。在树脂合成过程中，研究了反应温度，催化剂，阻聚剂等因素对合 产品的影响。通过L9(3^4)正交试验，得到了优化的工艺参数：反应温度为90℃，催化剂为N，N－二甲苯胺，用量1％；阻聚剂对苯二酚，用量0．5％，投料环氧树脂和丙烯酸的摩尔比为1：1．08。     

防止氟化铝母液脱硅工艺中铝、氟消耗方法研究

在氟化铝母液中添加氯化铝等可溶性铝盐,可有效地阻止钠,氟,铝间冰晶石固体物质的形成,从而达到防止氟化铝脱硅工艺中铝,氟的损耗,确保氟硅酸钠的产品质量,同时提高母液利用的经济效益。     

从精苯酸焦油废液中提取水泥减水剂的研究

研究了从精苯焦油废液中提取水泥减水剂的工艺过程．系统地分析了提取产品的各项物性指标．应用试验表明．对水泥的减水率达２０％．同时水泥的抗折强度和抗压强度均有所提高．由此可以看出该提取物是一种优良的水泥减水剂．     

N-十六烷基乙二胺二乙酸钠的合成及性能研究

采用大量无水乙二胺与1－Br－十六烷反应合成N－十六烷基乙二胺，然后与过量氯乙酸作用制备N－十六烷基乙二胺二乙酸，用NaOH中和，即得N－十六烷基乙二胺二乙酸钠。该产物在硬水中的差示稳定性为333，优于LAS。在相同测试条件下，产物的去污力高于LAS，发泡力明显低于LAS。