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31.
安阳化学工业集团有限责任公司“8·13”系统自1999年初投产以来,采用了3套PGC302型气相色谱仪分别对合成循环气、新鲜气、气柜出口半水煤气进行在线分析。但从2004年1月起,循环氢色谱仪对循环气中氢含量的分析值频繁波动,其测定准确度直接影响着系统氢氮比的调节效果以及合成氨产量的高低。为确保系统高负荷稳定生产,通过对影响色谱仪分析结果的因素进行分析,找到了引起分析值波动的主要原因,实施了切实可行的解决方案,提高了循环氢色谱仪的分析准确度。1循环氢色谱仪的配置和相关参数分析仪型号PGC302;检测器热导检测器;进样、反吹、柱… 相似文献
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介绍了国内外石油树脂的生产和技术发展状况,并对加氢催化剂的最新进展了作了较详细的论述,提出了发展我国加氢石油树脂的建议。 相似文献
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Biodegradable plastics (GSD) based on soy dreg (SD) were prepared by compression‐molding, with glycerol as the plasticizer and glutaraldehyde (GA) as the cross‐linker. The structure and properties of the GSD sheets were investigated by Fourier‐transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), scanning electron microscope (SEM), and tensile test methods. The results indicate that when GA content was 6.8%, the tensile strength (σb) of the sheet reached the maximum value of 14.5 MPa. Moreover, the strength and water resistance of the sheets coated with castor‐oil‐based polyurethane/nitrochitosan interpenetrating network (IPN) coating were significantly enhanced to 24.6 MPa in the dry state and 9.8 MPa in the wet state. Simultaneously, the test of biodegradability of the GSD sheet in a mineral salts medium containing microorganisms and agar proved that GSD could be fully biodegradable. This work has provided a novel way to utilize low‐cost SD to prepare biodegradable plastics. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 422–427, 2003 相似文献
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Xipeng Pu Xuejian Liu † Fagui Qiu Liping Huang 《Journal of the American Ceramic Society》2004,87(7):1392-1394
A novel method has been developed for the fabrication of silicon nitride reticulated porous ceramics (RPCs) with regulated structure, using polyurethane sponge as the template. This technique includes two centrifuging steps. In the first stage, the polyurethane sponges are coated with thin slurry through high-speed centrifuging. After the slurry on sponges dried, a high-strength green body without filled cells is obtained. In the second stage, because of improved adhesion between the body and the slurry after the first coating, the body with uniformly thick strut is produced by recoating the as-prepared green body with thixotropic slurry and centrifuging again. The loading content of slurry and the pore diameter of the RPCs body greatly depend on the slurry viscosity in the process of recoating. The strut diameter and pore diameter of the RPCs are effectively optimized by modulating the slurry viscosity. 相似文献
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Xiangming He Weihua Pu Jianguo Ren Li Wang Jiulin Wang Changyin Jiang Chunrong Wan 《Electrochimica acta》2007,52(25):7372-7376
The charge and discharge characteristics of lithium batteries with sulfur composite cathodes have been investigated. The sulfur composites showed novel electrochemical characteristics. The analysis of the differential capacity indicated that the discharge process showed two voltage plateaus of 2.10 V and 1.88 V, and the charge process also presented two voltage plateaus of 2.22 V and 2.36 V. The overcharge test showed that the composite cannot be charged over 4.0 V, the voltage always stopped at about 3.9 V during charging, indicating that the composite presented the intrinsic safety for the overcharge of lithium batteries. The overcharge can cause serious safety problem for the conventional Li-ion batteries. The overcharge test also showed that the batteries with sulfur composite were destroyed when the upper cut-off voltage was over 3.6 V. However, the composite presented good reversible capacity after it was deep discharged even to 0 V. It showed stable cycleability and high cycling capacity of 1000 mAh g−1 when cycling between 0.1 V and 3.0 V, indicative of the different characteristic from the conventional oxide cathode materials. The prototype polymer battery with the composite cathode material presented the energy density of 246 Wh kg−1 and 401 Wh L−1. 相似文献