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91.
目的:顶空加热提取北柴胡茎叶的低温挥发性成分,建立其GC-MS快速分析方法,实现老药工采药感官经验的客观阐明。方法:选择北柴胡的茎叶,顶空提取结合气相色谱-质谱分析,确定低温挥发性成分的结构和相对含量。结果:顶空加热提取结合GC-MS分析,鉴定柴胡茎叶中24个挥发性化学成分。结论:顶空提取与GC-MS联用可以快速建立柴胡茎叶的低温易挥发性成分表征体系,初步实现了老药工采药经验"气味"的物质基础的阐明。 相似文献
92.
The depletion of fossil fuels and increasing demand leads to research in alternate fuels. The alternate fuels are bio-degradable, renewable and non-toxic. Many types of oils are re-used in biodiesel production, considering their availability, among which linseed oil is the most significant one. Injection timing plays a major role among various injection parameters which affects its performance and emission characteristics. This paper focuses on experimental investigation on a single cylinder, four-stroke direct injection diesel engine with output of 5.2?kW at 1500?rpm at various injection timings, 20, 23, 26 degree BTDC for observing the performance and emission characteristics of direct injection diesel engine using methyl esters of linseed oil and its blends. The blends are B10, B20, and fuel characteristics are observed. The results show that when compared with diesel it gives an increase in BTHE and reduction in SFC. Both the biodiesel blends give lesser NOx. Slightly higher CO and HC emission were found. The performance and emissions were increased in when injection increased. 相似文献
93.
Electro-osmosis is an established method of dewatering fine soils, sediments, and sludge (SSS). The efficiency of electro-osmotic treatment is controlled by the electrical resistance of the system. Due to an increase in SSS resistance during treatment, its cost efficiency is reduced, limiting the widespread use of this technique. The aim of this paper is to discuss the main reasons for the increase in SSS resistance during treatment and then to analyze the most recent and widely spread modifications to classical electro-osmotic treatment that attempt to combat these issues and improve the efficiency of the technique. These modifications to electro-osmotic treatment are polarity reversal, an intermittent current, the injection of chemical solutions at the electrodes, and the use of geo-synthetics. The paper discusses the relevant research on the above adaptations, and the advantages and disadvantages of each are evaluated and compared using the available laboratory and field tests in the literature on electro-osmotic dewatering research. All four methods of modification are shown to provide significant improvements and can be successfully translated to the field for greater use. However, the improvements they bring about may not be sufficient to warrant their general use in geotechnical applications. 相似文献
94.
An experimental study is conducted to evaluate the use of rubber seed oil with diesel at a proportion of 20% by volume (RSO20) in a constant speed (1500?rpm) direct injected four-stroke air-cooled single-cylinder compression ignition engine at different injection timings (24°, 27°, 30°, 33° bTDC (before top dead centre)). A series of tests were conducted at various engine load conditions at the rated power of 5.9?kW. The injection pressure was maintained at 200?bar. As a result of investigations, at the full load condition, the brake thermal efficiency of RSO20 at 30° bTDC is high compared with other injection timings and brake energy fuel consumption is increased when advancing injection timing. There is a significant reduction in unburned hydrocarbon emission and carbon monoxide emission, and the oxides of nitrogen emission (NOx) is increased when advancing the injection timing. 相似文献
95.
功能化注塑机是特种具有注塑功能的复合型成型加工设备,驱动注塑技术的科学发展。提出了功能化注塑机的内涵,分析了功能化注塑机科学发展十个方面存在的理念问题,简述了功能化注塑机的科学发展的八个特点,研究了十类功能化注塑机的技术发展现状及科学发展要点,介绍了功能化塑料件引领创新创造功能化注塑机的实例及一种自主创新的功能化的工具箱包注吹机。 相似文献
96.
注塑机绿色设计是实现保护环境质量、尽量减少能源与其他自然资源的消耗、用更清洁和更有效的技术、支持生态环境完整性的可持续发展的基础。分析了注塑机绿色设计的属性,阐述了注塑机的机构、动力驱动系统、控制系统、清洁技术等绿色设计存在的问题及研发重点,探讨了注塑机的柔性模块化的绿色设计,研究了绿色设计技术的科学发展及绿色设计服务于绿色注塑工程的发展领域,指出绿色设计服务于绿色注塑工程技术发展才有市场价值。文中以绿色设计为准则,列举并分析了较多的设计中常见缺陷及其产生的原因,并提出了解决的建议和措施,对于注塑机绿色设计具有一定的借鉴意义。 相似文献
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