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101.
A study of conversion of organic matter of brown coal in supercritical water (SCW) at 30 MPa, 400−760 °C and continuous supply of coal-water slurry (CWS) into a tubular reactor is presented. It was found that 48−63% (depending on the SCW temperature) of coal organic matter (COM) is ejected from CWS coal particles as liquid and gaseous products when they move through the reactor. We termed this stage of SCW conversion as dynamic conversion (DC) of coal. It turns out that the particles which underwent the DC stage did not aggregate in the reactor during static conversion (SC) within a coal layer due to continuous pumping through this layer. The experimental data on the composition of DC and SC products, degree of coal conversion, and the data on the degree of combustion of carbon in the presence of oxygen are given.  相似文献   
102.
In this paper we present the results of the Working Group on Design Synthesis and Measurement. This group explored the issues that separate and bind software engineering and VLSI design. The issues on which we comment are design views and tradeoff, levels of abstraction and their importance, and design methodologies and their effect on decisions. We also examine the support environments needed to facilitate design in VLSI and software engineering, state-of-the-art of silicon compilation today, and the types of problems that are best suited to silicon compilation.  相似文献   
103.
A membrane-based process to produce protein isolates from seeds of oriental mustard (Brassica juncea) was developed by modifying a method originally developed for rapeseed. The optimized process consisted of extraction at pH 11, ultrafiltration with concentration factor 4, diafiltration with diavolume 3, and precipitation at pH 5. The process, based on defatted oriental mustard seed containing 45–50% protein, recovered 81% of the protein in useful products: 47.3% in precipitated protein isolate (PPI), 3.8% in soluble protein isolate (SPI), and 13% in meal residue. Mass yields were 21.9% in PPI, 2.8% in SPI, and 38.4% in meal residue. The losses in the system included ∼10% loss of nonprotein nitrogen, and <9% into permeate and transfer losses. The PPI compared favorably with soy protein isolate in typical meat products in terms of color, texture, and flavor. The work confirms that oriental mustard is a potentially useful source of edible protein.  相似文献   
104.
This paper describes the results of a study on use of the adsorption–regeneration technique for recovery of dissolved allyl isothiocyanate(AITC) which is present in significant quantities in steam distillation condensate of mustard essential oil (MEO). Equilibrium and dynamic breakthrough studies were carried out. The adsorbents used were polymeric adsorbents: Amberlite XAD‐2, Amberlite XAD‐4, Amberlite XAD‐7, NPA‐1 and NPA‐2. The results obtained indicate that Amberlite XAD‐4 is the best amongst these various adsorbents. AITC recoveries in excess of 95% were obtained, indicating the feasibility of this approach. Further, since no chemical reactions are involved the recovered AITC retains its ‘natural’ origin. © 2000 Society of Chemical Industry  相似文献   
105.
Influence of sulphur mustard (SM), a chemical warfare agent, on mechanical and transport properties of poly(ethyleneterephthalate) (PET) films was investigated. The objective of the study was to assess the agent–substrate interaction. SM induces changes in PET in that the elongation as well as strength of SM-exposed films decreases considerably. The reduction in percentage elongation at break is very significant, perhaps because of the antiplasticizing effect of SM on PET. The breakthrough time (BTT) of SM is higher for the film, which showed greater resistance to amine etching. The critical dissolution time measurement substantiates the data on mechanical behaviour of SM-exposed films. © of SCI.  相似文献   
106.
Three methods of quantifying total phenolic compounds in marine brown algae were compared for their ability to measure accurately known concentrations of phloroglucinol in the presence of a protein, bovine serum albumin (BSA). These methods were: (1) a Folin-Ciocalteu assay for compounds dissolved in 80% methanol, (2) a Folin-Ciocalteu assay for compounds dissolved in 75% methanol-25% trichloroacetic acid, and (3) an assay in which polyvinylpolypyrrolidone (PVPP) was used to remove phenolic compounds in order to quantify nonphenolic, Folin-Ciocalteu-reactive materials. The Folin-Ciocalteu assay used with compounds dissolved in 80% methanol was the method that produced the most consistent results. It was also the assay in which the presence of proteins interfered least with the measurements of phloroglucinol and the assay that was easiest to conduct. The presence of TCA decreased the pH of the extracting solution and increased the amounts of proteins in solution. These proteins later interfered with the Folin-Ciocalteu reaction. TCA effectively bound proteins when protein concentrations were low but not when protein concentrations were high. The amount of phloroglucinol removed by PVPP varied widely and was dependent on phloroglucinol concentration, making this an unreliable method for quantifying phenolic concentrations. The Folin-Ciocalteu assay will measure some nonphenolic substances when brown algae are extracted in 80% methanol; however, inFucus gardneri, nonphenolic substances were at most 5% of the material quantified by the assay.  相似文献   
107.
为分析我国煤矿死亡事故发生的规律和准确判断未来我国煤矿的整体安全生产形势,根据2009—2018年我国煤矿死亡事故统计数据,从煤矿事故发生级别、事故类型2个维度对我国的煤矿生产安全事故进行了研究。通过SPSS 25.0软件建立Brown线性趋势模型,并对我国2009—2018年煤矿百万吨死亡率进行验证,最后预测2019—2021年我国煤矿百万吨死亡率。结果表明2009—2018年煤矿事故起数和死亡人数处于持续下降趋势,我国煤矿安全形势持续稳定向好;在事故发生级别上,一般事故发生的事故起数最多,累计造成的人员死亡也是最高,其次是较大事故和重大事故,特别重大事故发生起数在2016年出现了回升,造成了大量人员伤亡,但是2017年出现回落,没有发生特大事故;在事故类型中,顶板事故发生频率最高,瓦斯事故是一次伤害造成死亡人数最多的;Brown线性趋势模型对2009—2018年煤矿百万吨死亡率验证表明,相对误差基本上都在30%以内,R^2=0.931,接近于1,均方根误差(RMSE)和正态化的BIC均较小,表明Brown线性趋势模型模型的拟合效果比较好,预测精度较高。对我国煤矿事故发生规律的研究和煤矿百万吨死亡率的预测验证分析,使煤矿企业制定完备的安全管理措施和避免煤矿事故的发生具有重要意义。  相似文献   
108.
In the last thirty or so years, architects have embraced all manner of computer softwares and hardwares. This has often resulted in convoluted forms and a concentration on the part of architects to solve fabrication complexities at the expense of dexterous design explorations. Artist, designer and educator Andrew Kudless reminds us of the messy, illogical and contradictory aspects of design development, and that we have yet to develop something as multivalent in its evocative suggestions as the old-fashioned ‘hairy’ sketch.  相似文献   
109.
A closed-form solution is presented in this paper for the prediction of displacements around circular openings in a brittle rock mass subject to a hydrostatic stress field. The rock mass is assumed to be governed by Hoek–Brown yield criterion and a non-associated flow rule is used. For the elastic–brittle–plastic analysis of circular openings in an infinite Hoek–Brown medium, the existing analytical solutions were found to be incorrect. The present closed-form solution is based on a theoretically consistent method and the solution does not require the use of any numerical method.The present closed-form solution was validated by using the finite element method. In the finite element analysis, the infinite boundary was simulated “exactly” by using the newly developed elastic support method. Several cases were analyzed and the present closed-form solutions for stresses and displacements were found to be in an excellent agreement with those obtained by using the finite element method.  相似文献   
110.
本文通过工艺试验,研究使用CO2饱充结合磷浮清净技术,对碳酸法糖厂本榨季赤砂糖及陈旧赤砂糖(存放时间6个月以上)回溶糖浆进行澄清脱色处理。试验结果表明,CO2饱充结合磷浮清净技术对陈旧赤砂糖回溶糖浆具有优异的脱色效果,脱色率达60%以上,但对榨季赤砂糖回溶糖浆脱色效果不明显,总脱色率仅为30%左右。主要原因是CO2饱充对贮存不同时间赤砂糖的脱色作用具有明显的选择性,对碳酸法糖厂刚生产的赤砂糖几乎没有脱色作用。  相似文献   
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