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91.
为研究双热源联合循环的热力性能极限,构建了两介质热功转换系统理想热力学模型,并提出了驱热力过程的基本概念。通过分析热机循环区间与热泵循环区间过程功量之间的关系,对驱热力过程进行分类,并通过输出功量占比进行定量分析。构建并求解了顺流型和逆流型驱热力过程函数。分析了不同类型驱热力过程在理想条件下的热力特性与性能极限。研究结果表明:顺流型驱热力过程的最大过程功量大于逆流型,且放热介质与吸热介质间的温度交叉现象更为明显。吸热介质等效温升可用于判断驱热力过程类型,其最大值表征了输出功量极限。实际系统的评价研究指出,串联型联合循环的总换热量是基本型ORC的1.97倍,更适用于同时具有热电需求的场合。但其净输出功效率(6.55%)、效率(26.61%)、热力完善度(36.38%)均显著低于基本型有机朗肯循环。双热源联合循环实际系统的热力性能提高方法值得研究。本研究可为不同类型两介质热功转换系统的热力性能极限与评价提供理论指导。 相似文献
92.
Wensen Liu Na Xu Hongyan Yuan Songyan Li Linna Liu Zhaoyang Pu Jiayu Wan Huiwen Wang Yaping Chang Ruisheng Li 《International journal of molecular sciences》2013,14(6):12401-12410
Ricin toxin binding subunit B (RTB) is one of the subunits of the ricin protein. RTB has been used as adjuvant, but little is known about its mechanism. In this study, we found that RTB increased not only nitric oxide (NO) release, but also tumor necrosis factor (TNF)-α and interleukin (IL)-6 production in mouse macrophage cell line RAW264.7 cells. They subsequently exhibited enhanced ConA-induced T-cell and LPS-induced B-cell proliferative responses. We also examined the cytokines that were produced from splenocytes following in vitro RTB administration. Increased levels of IL-2, interferon (IFN)-γ and TNF-α were observed, while IL-4 and IL-5 were unaffected. These results demonstrate that recombinant RTB can act on the immune system and activate T-cells by introducing a Th1 immune response. Th1 cells might be the primary cellular target affected by RTB. Our results suggest that the recombinant RTB can promote the activation of macrophages and has a beneficial effect on immunomodulatory activity. 相似文献
93.
Song Xinrong Song Kunyang Ding Sha Chen Yaping Lin Yuanbin 《Journal of Industrial and Engineering Chemistry》2013,19(2):416-420
Poly[N,N′-(2-amino-5-carboxybutyl-1,3-phenylenedimethylene)-2,2′-diamino-4,4′-bithiazole] was synthesized and characterized with Fourier transform infrared spectroscopy (FT-IR) and scanning electron microscopy (SEM). Anhydrous electrorheological (ER) fluids were prepared using the polymer particles as disperse phase and bromodiphenylmethane as a disperse medium. Rheological measurements were carried out via a rotational rheometer to investigate the effects of electric field strength and the polymer particle content on the ER properties. Results indicate that suspensions of the polymer particles containing amino and carboxybutyl groups in bromodiphenylmethane exhibit a substantial ER effect. 相似文献
94.
通过对倾斜角35°首尾相连的三分螺旋折流板换热器的数值模拟,展示了其壳侧通道内流体在典型切面上的流场和流线分布,以及典型切面上典型直线的流动和换热参数分布,并与性能测试结果进行了对比。结果表明,数值模拟结果与实验结果是吻合的。螺旋折流板形成的近似螺旋通道,使换热器壳侧流体受离心力和向心力共同作用形成了迪恩涡二次流,且在每个螺旋周期内都存在;二次流增强了主流区域流体与靠近壁面流体的掺混,使得壳侧典型切面上中心线和折流板外缘直线的轴向速度较大;除主流中心区域外,壳侧流体在二次流的作用下具有均匀的湍流动能;二次流所在区域内,壳侧同心柱面内典型直线上换热系数相差不大,但由于二次流能使其附近区域传热面上的流体得到不断卷吸掺混,由此强化传热。 相似文献
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97.
高炉煤气脱硫是实现钢铁行业多工序全流程超低排放的关键。高炉煤气中主要有机硫组分是羰基硫(COS),常用γ-Al2O3基催化剂水解脱除,但是其抗氧性能有待提高。采用共沉淀法制备了Ti0.5Al和K0.2Ti0.5Al催化剂,考察了催化剂在含氧气氛下的COS水解催化性能,并分析了氧体积分数对COS转化率和H2S产率的影响规律。活性测试结果表明,Ti0.5Al催化剂的初始COS转化率接近90%,随着反应时间增长效率逐渐降低至60%以下;K0.2Ti0.5Al催化剂在0.5% (体积分数) O2的气氛下持续反应22 h后,其COS转化率仍可保持在93.44%。表征结果显示,催化剂失活后比表面积大幅减小,表面碱性显著减弱。此外,活性中心Al原子硫酸化是导致催化剂失活的主要原因,而硫酸盐的沉积为次要原因。原位红外结果表明,K的引入可显著减弱O2在催化剂表面的吸附,并且阻断中间过渡物种的氧化,这是K提高催化剂抗氧性能的关键。 相似文献
98.
A puffed food using salted duck egg white and starch as ingredients was produced by using a novel pulsed-spouted microwave vacuum drying (PSMVD) technique. In this study, three types of samples (ratios of salted duck egg white to starch 1:10, 3:10, and 5:10) were prepared and the moisture content of these samples was dehydrated to about 12% in a PSMVD dryer, then the samples were under different microwave powers (1.34 kW, 2.01 kW, and 2.68 kW) for puffing. The product volume expansion ratio, textural crispness (breaking forces), color parameters (L*, a* and b*), and sensory scores were determined. It was observed that microwave power and different ratios of salted duck egg white to starch had a significant effect on the expansion effect of the samples. The results indicated that the best product quality was obtained under the ratio of salted duck egg white to starch at 3:10 and microwave power at 2.01 kW. 相似文献
99.
Masood Jan Zhixin Liu Chenxi Guo Yaping Zhou Xuwu Sun 《International journal of molecular sciences》2022,23(9)
Cotton refers to species in the genus Gossypium that bear spinnable seed coat fibers. A total of 50 species in the genus Gossypium have been described to date. Of these, only four species, viz. Gossypium, hirsutum, G. barbadense, G. arboretum, and G. herbaceum are cultivated; the rest are wild. The black dot-like structures on the surfaces of cotton organs or tissues, such as the leaves, stem, calyx, bracts, and boll surface, are called gossypol glands or pigment glands, which store terpenoid aldehydes, including gossypol. The cotton (Gossypium hirsutum) pigment gland is a distinctive structure that stores gossypol and its derivatives. It provides an ideal system for studying cell differentiation and organogenesis. However, only a few genes involved in the process of gland formation have been identified to date, and the molecular mechanisms underlying gland initiation remain unclear. The terpenoid aldehydes in the lysigenous glands of Gossypium species are important secondary phytoalexins (with gossypol being the most important) and one of the main defenses of plants against pests and diseases. Here, we review recent research on the development of gossypol glands in Gossypium species, the regulation of the terpenoid aldehyde biosynthesis pathway, discoveries from genetic engineering studies, and future research directions. 相似文献
100.
田庄选煤厂分选产品燃烧过程中汞的释放规律 总被引:1,自引:0,他引:1
通常煤中含有0.1×10-6~0.15×10-6的汞,在燃烧和气化过程中被排放到空气中.由于其高挥发性和毒性,特别是会对神经系统造成影响,所以成为人们关注的一种重要的重金属元素.对河南省田庄选煤厂的一种T煤进行了分选,根据分选产品的TGA和DTG曲线分析了煤样的燃烧特性,通过对不同温度段元素汞和氧化态汞的采集和测定,研究了不同分选产品的汞释放行为.结果表明,末原煤、末中煤和末精煤具有相似的燃烧和汞释放行为.烟气中元素汞的含量大于氧化态汞的含量.通过物理分选,煤样中部分无机汞可以被富集到重产品中. 相似文献