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81.
薛恒新 《南京理工大学学报(自然科学版)》1984,(Z2)
本文是某机床制造企业研制销售信息系统这一实际工作的阶段性结果。文章从机床制造企业对销售信息系统的迫切需要出发,在分析人工销售信息系统弊病的基础上,通过系统分析、系统设计,制定了一个具体方案。 本方案从销售信息系统的特点考虑,在代码制定及校验、分析数据关系、输入数据纠错、文件记录格式和组织形式设计等方面作了较为深入的讨论。 相似文献
82.
Hans Niederprüm 《Angewandte Chemie (International ed. in English)》1975,14(9):614-620
Metal layers can be deposited from aqueous solutions not only by electric current as in electroplating but also by strong reducing agents. Chemical deposition of nickel on metallic and nonmetallic substrates, together with the long-known silvering of glass, are the most widespread examples. This remarkable reaction has recently found a variety of industrial applications mainly in the preparation of corrosion-resistant, hard, and wear-resistant protective layers, in the metallizing of plastics, and in electronics. 相似文献
83.
K. Zosel 《Angewandte Chemie (International ed. in English)》1978,17(10):702-709
Extraction with supercritical gases combines, to a certain extent, the characteristics of both distillation and extraction; the term “destraction” is therefore proposed for this method of separation. The principles of the method are illustrated in this article by a series of color photographs comparing extraction and destraction. Of the practical uses of this new method may be mentioned the separation of cod-liver oil into 50 fractions, each differing in saponification value and iodine number, by means of supercritical ethane and, in particular, the decaffeination of raw coffee with supercritical carbon dioxide. 相似文献
84.
R. Eggers 《Angewandte Chemie (International ed. in English)》1978,17(10):751-754
Criteria for the design and construction of plant for obtaining carrier material or extracts are discussed for the example of the extraction of natural products with supercritical carbon dioxide. The parameters to be established and the course of the process in a large-scale plant are indicated. Plant engineering and optimization must be attuned to specific process-technological and construction problems. 相似文献
85.
K. I. Sakodynskii S. A. Volkov K. F. Khalilov V. I. Reznikov V. Yu. Zel'venskii 《Chromatographia》1985,20(9):538-542
Summary Chromatography is carried out under the conditions of fluidization, in long, straight tubes under organized and non-organized
conditions. Under non-organized conditions the column is filled only with a sorbent. In organized conditions, either metal
coils are added into the column or a segmented column is utilized with metal grids. The results obtained are compared to those
obtained under fixed-bed conditions when the column is completely filled with the sorbent. Organized fluidized beds provide
a significant decrease in longitudinal bandspreading. 相似文献
86.
不同马尾松无性系测定林生物量及养分积累的比较 总被引:1,自引:0,他引:1
选择福建漳平五一国有林场7年生马尾松无性系测定林为研究对象,通过对参试40个马尾松无性系不同器官生物量及N、P、K含量的测定,进行不同无性系生物量及养分积累量的比较,结果表明:参试无性系全株生物积累量平均为15.94 kg.株-1,其中M7号无性系的生物量最大,但养分消耗量也较大。M18号无性系的生物产量较高,而N积累量小于平均值的20%,初步判断为N营养利用效率较高基因型。M4、M5、M7、M9、M13、M14、M18、M22、M23、M26和M30无性系的干材生物量大于平均值20%,但P和K营养积累量均小于平均值的20%,属于对林地养分消耗较小的高产无性系。 相似文献
87.
88.
针对当前工业锅炉炉水协调过程中,加磷酸盐主要以人工为主,成本高、劳动强度大、存在很多人为因素,导致控制不连续的问题,提出一种新的炉水协调磷酸盐PLC智能控制方法,给出PLC智能控制系统的总体结构,主要包括被控对象、变频器、可编程序控制器(PLC)、pH表、磷酸根表等。两台变频器用于控制两台加药泵,PLC 智能控制器用于实现R值计算、加药品种选择和加药泵转速控制。介绍了R值计算的详细过程,通过加药品种选择算法和加药泵转速控制算法,实现PLC控制器对炉水协调磷酸盐的控制功能。实验结果表明,所提方法不仅能够将水质控制在合理范围内,而且控制精度高,所需时间少。 相似文献
89.
Industrial hazardous waste management involves the collection, transportation, treatment, recycling and disposal of industrial hazardous materials that pose risk to their surroundings. In this paper, a new multi-objective location-routing model is developed, and implemented in the Marmara region of Turkey. The aim of the model is to help decision makers decide on locations of treatment centers utilizing different technologies, routing different types of industrial hazardous wastes to compatible treatment centers, locations of recycling centers and routing hazardous waste and waste residues to those centers, and locations of disposal centers and routing waste residues there. In the mathematical model, three criteria are considered: minimizing total cost, which includes total transportation cost of hazardous materials and waste residues and fixed cost of establishing treatment, disposal and recycling centers; minimizing total transportation risk related to the population exposure along transportation routes of hazardous materials and waste residues; and minimizing total risk for the population around treatment and disposal centers, also called site risk. A lexicographic weighted Tchebycheff formulation is developed and computed with CPLEX software to find representative efficient solutions to the problem. Data related to the Marmara region is obtained by utilizing Arcview 9.3 GIS software and Marmara region geographical database. 相似文献
90.
Heracleum sphondylium L. subsp. ternatum (Velen.) Brummitt. commonly known as “hogweed” is traditionally used to manage several human ailments. This investigation assessed, for the first time, the enzyme inhibitory properties, antioxidant activity, phytochemical profile, antimutagenic, and antimicrobial potential of the ethyl acetate, methanol, and water extracts of H. sphondylium. We also established the possible interactions of identified phenolic compounds with cholinesterases, amylase, glucosidase, and tyrosinase using in silico docking studies. Chlorogenic acid was found in high amounts in the methanol extract of H. sphondylium. The methanol extract was an effective inhibitor of acetylcholinesterase (1.70 mg galantamine equivalent (GALAE)/g extract) while the ethyl acetate extract showed pronounced inhibitory action against butyrylcholinesterase (1.77 mg GALAE/g extract). The extracts exhibited low inhibition against amylase (0.12-0.84 mmol acarbose equivalent (ACAE)/g extract) and a more pronounced inhibition against glucosidase (2.29–3.65 mmol ACAE/g extract). In silico results showed that rutin and quercetin (-70.4 and -72.2 Kcal/mol, for rutin and quercetin respectively) docked to the enzymatic cavity of acetylcholinesterase but these phenolic compounds showed less affinity with butyrylcholinesterase (-15.0 and -5.2 Kcal/mol, for rutin and quercetin respectively). The extracts did not induce any mutations on the bacterial strains, while they have excellent antimutagenic capacity against well-known mutagens (inhibition values 98%, 97% and 96%). The methanol extract (0.78 mg/ml) showed moderate antifungal activity while the ethyl acetate extract (0.78–3.12 mg/ml) showed weak to moderate antimicrobial activity. This study provides valuable baseline data which might serve for the development of future pharmacophores for the management of human ailments. 相似文献