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1.
In the testing of mine monitoring systems, a software package was developed for the mine monitoring test facility designed at West Virginia University. The software establishes delay times of sensor input to annunciation for single alarms and multiple simultaneous alarms. The alarm measurement techniques for the test fixture are described, as is the software developed to analyze and graph monitoring system response data. Also included is the analysis capability of the facility, the criteria for evaluating mine monitoring systems, and typical test data from a sample system.  相似文献   
2.
Sintered Halon G-80, a polytetrafluoroethylene (PTFE) resin available commercially in powdered form, is a superb diffuse reflector. Sintered Halon has 96% absolute reflectance at wavelengths between 300 nm and 380 nm, and about 98% absolute reflectance above 380 nm. It is chemically inert, is mechanically strong, does not fluoresce, and the high reflectance is easy to maintain over time. We have used sintered Halon as a lining in light integration boxes of water Cherenkov detectors. Preparation involves packing Halon powder into a mold to a specific density, then heating the material almost to the melting point (sintering). A method of preparing sintered Halon is presented. Physical properties of sintered Halon have been measured and we present those results here as well.  相似文献   
3.
Summary The inviscid separated flow past slender rhombic cones at incidence is considered. A complex potential is constructed, in a suitable cross-flow plane, which satisfies the conditions on the wing, at infinity, and on the vortex system which models the separated flow. The results obtained both extend earlier results to small incidence, and explain an anomaly within those results.  相似文献   
4.
Privett OS  Nutter LJ 《Lipids》1967,2(2):149-154
A detailed procedure for quantitative determinations of molecular species of lecithins is described and applied to several lecithins isolated from natural sources. The method is based on the conversion of lecithin to acetylated 1,2-diglycerides and analysis of these compounds by methodology used for the determination of triglyceride structure. The preparation of the acetylated 1,2-diglycerides was carried out via hydrolysis with phospholipase C and acetylation of the resultant, 1,2-diglycerides with pyridine-acetic anhydride. Preparation of acetylated 1,2-diglycerides from lecithin by acetolysis with acetic acid-acetic anhydride was shown to be accompanied by intermolecular as well as intramolecular rearrangement of the fatty acids. The structure of the acetylated 1,2-diglycerides was determined by a combination of argentation-TLC and pancreatic lipase hydrolysis using internal standards for quantification. The method was applied to lecithins isolated from milk serum, egg, soybean, safflower seed and wheat germ lipids.  相似文献   
5.
Computer simulation is a useful tool for benchmarking electrical and fuel energy consumption and water use in a fluid milk plant. In this study, a computer simulation model of the fluid milk process based on high temperature, short time (HTST) pasteurization was extended to include models for processes for shelf-stable milk and extended shelf-life milk that may help prevent the loss or waste of milk that leads to increases in the greenhouse gas (GHG) emissions for fluid milk. The models were for UHT processing, crossflow microfiltration (MF) without HTST pasteurization, crossflow MF followed by HTST pasteurization (MF/HTST), crossflow MF/HTST with partial homogenization, and pulsed electric field (PEF) processing, and were incorporated into the existing model for the fluid milk process. Simulation trials were conducted assuming a production rate for the plants of 113.6 million liters of milk per year to produce only whole milk (3.25%) and 40% cream. Results showed that GHG emissions in the form of process-related CO2 emissions, defined as CO2 equivalents (e)/kg of raw milk processed (RMP), and specific energy consumptions (SEC) for electricity and natural gas use for the HTST process alone were 37.6 g of CO2e/kg of RMP, 0.14 MJ/kg of RMP, and 0.13 MJ/kg of RMP, respectively. Emissions of CO2 and SEC for electricity and natural gas use were highest for the PEF process, with values of 99.1 g of CO2e/kg of RMP, 0.44 MJ/kg of RMP, and 0.10 MJ/kg of RMP, respectively, and lowest for the UHT process at 31.4 g of CO2e/kg of RMP, 0.10 MJ/kg of RMP, and 0.17 MJ/kg of RMP. Estimated unit production costs associated with the various processes were lowest for the HTST process and MF/HTST with partial homogenization at $0.507/L and highest for the UHT process at $0.60/L. The increase in shelf life associated with the UHT and MF processes may eliminate some of the supply chain product and consumer losses and waste of milk and compensate for the small increases in GHG emissions or total SEC noted for these processes compared with HTST pasteurization alone. The water use calculated for the HTST and PEF processes were both 0.245 kg of water/kg of RMP. The highest water use was associated with the MF/HTST process, which required 0.333 kg of water/kg of RMP, with the additional water required for membrane cleaning. The simulation model is a benchmarking framework for current plant operations and a tool for evaluating the costs of process upgrades and new technologies that improve energy efficiency and water savings.  相似文献   
6.
The objective of this review is to summarize research efforts and case studies to date of the environmental impacts from dairy processing. The pervasiveness of greenhouse gas emission, water use, consumer waste, and other environmental impacts of dairy are described. An outline of the method of choice, the life cycle assessment, for conducting research and deciding appropriate allocation of the impacts is provided. Specific research examples in dairy processing highlight how the representative final product is associated with environmental impacts to air, water, and land. The primary conclusion from the study was the usefulness of life cycle assessment methodology and the need for further research due to limited studies, variable data, and the magnitude of environmental impact.  相似文献   
7.
Field evaluation of coal mine monitoring and control systems yields data on installation and maintenance, but does not provide a full evaluation of these systems under all possible conditions. Also, the differences in installations and configurations do not allow the performance of different systems to be measured and compared. Under contract of the United States Bureau of Mines (USBM), the West Virginia University (WVU) Department of Electrical Engineering has designed criteria for evaluation of monitoring systems, and a test facility for simulation of mine conditions. This facility provides evaluation of monitoring and control systems under both normal and abnormal conditions. This paper describes the test criteria chosen, the design of the test facility, and the experiences of tests performed on mine monitoring systems to date.  相似文献   
8.
Metallurgical and Materials Transactions A - The current study reports the detailed analysis of an observation of the local pinning of a slowly moving austenite-ferrite interface by a single...  相似文献   
9.
Kwok  T. W. J.  Gong  P.  Xu  X.  Nutter  J.  Rainforth  W. M.  Dye  D. 《Metallurgical and Materials Transactions A》2022,53(2):597-609
Metallurgical and Materials Transactions A - A novel medium manganese steel with composition Fe–8.3Mn–3.8Al–1.8Si–0.5C–0.06V–0.05Sn was developed and...  相似文献   
10.
Summary Several chemical constants have been determined on the depot fats taken from four strains of chickens and four strains of turkeys. Similar analyses have been run on depot fat from cold storage turkey and on “commercial” samples of chicken and turkey fat obtained from the wholesale market. There is no significant difference in the constants of fats from various breeds of chicken. The fats from various breeds of turkey are also similar. Furthermore, there is no outstanding difference between the constants of turkey and chicken fats, though turkey fats tend to have higher fatty acid and acetyl values and lower iodine and thiocyanogen values, and a somewhat greater instability. Thus it is not easily possible to distinguish between turkey and chicken fats by the usual analytical procedures. From the Department of Biology and Biological Engineering, Massachusetts Institute of Technology, Cambridge, Mass. This research has been supported by a grant from Continental Foods, Inc., Hoboken, New Jersey. Presented before the Division of Biological Chemistry, at the 105th meeting of the American Chemical Society, Detroit, Michigan.  相似文献   
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