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81.
Beef spleens were freed of undesirable capsular and internal connective tissue by passage through a Beehive Model AU 4171 deboner fitted with a desinewing head. The resulting product (called mechanically separated spleen or MSS) was recovered at a 79% yield and contained 17.0% protein, 2.9% fat and 762 ppm iron. The effect of mechanical separation on protein quality was determined by protein efficiency ratio (PER). Rats fed MSS and whole spleen diets exhibited significantly greater weight gains than those fed casein. PER values for whole spleen (2.4) and MSS (2.3) were not significantly different. The PER value for casein (2.5) was significantly higher than that of MSS but not whole spleen.  相似文献   
82.
Nicotinamide hemochrome has been reported as one of the potential pigments involved in the pinking defect of cooked, uncured turkey. Reflectance spectroscopy has been the principle method used to identify this pigment. However, a reliable, easy method to quantify its presence is needed. Cooked turkey samples (containing 0, 0.25, 0.50, 1.0, or 2.0% nicotinamide or 0, 75, or 150 ppm sodium nitrite) were treated with potassium ferricyanide, hydrogen peroxide, sodium dithionite and light (1076 lux; 0 and 2 min). Treated samples were analyzed with a reflectance spectrophotometer in the visible range. Analysis of reflectance wavelength ratios of the nicotinamide pigment and correlations of those values, indicated that the ratio of 537/553 nm best represented the relative quantity of nicotinamide hemochrome (r=0.933) with minimal interference from nitrosylhemochrome (r=0.029).  相似文献   
83.
Differential Scanning Calorimetry (DSC) has been used to study the thermal properties of fish muscle proteins and to measure the extent of their denaturation under various processing conditions. Fish myosin was susceptible to denaturation by frozen storage and dehydration. Denaturation of certain fish proteins was partially reversible. Although fish myosin was very unstable, its thermal stability was found to increase in species adapted, to higher environmental temperatures.  相似文献   
84.
The precepts behind the macroscopic and microscopic quantizations of the electromagnetic field in a dielectric are discussed. Using the correspondence principle, it is demonstrated that the macroscopic quantization procedure leads to incorrect equations of motion of embedded two-level atoms. The fundamental nature of the Lorentz viewpoint of electrodynamics is discussed.  相似文献   
85.
An experimental protocol (workflow) has been developed for time‐lapse x‐ray nanotomography (nano‐CT) imaging of environmentally driven morphological changes to materials. Two case studies are presented. First, the leaching of nanoparticle corrosion inhibitor pigment from a polymer coating was followed over 14 days, while in the second case the corrosion damage to an AA2099 aluminium alloy was imaged over 12 hours. The protocol includes several novel aspects relevant to nano‐CT with the use of a combination of x‐ray absorption and phase contrast data to provide enhanced morphological and composition information, and hence reveal the best information to provide new insights into the changes of different phases over time. For the pigmented polymer coating containing nominally strontium aluminium polyphosphate, the strontium‐rich components within the materials are observed to leach extensively whereas the aluminium‐rich components are more resistant to dissolution. In the case of AA2099 it is found that the initial grain boundary corrosion is driven by the presence of copper‐rich phases and is then followed by the corrosion of grains of specific orientation.  相似文献   
86.
Optimization-based planning for the stochastic lot-scheduling problem   总被引:3,自引:0,他引:3  
We describe a finite-horizon stochastic optimization model for the stochastic lot-scheduling problem and procedures for finding near-optimal solutions. Several different products are produced by a single-stage process with significant changeover times and costs, and the demand for these products is random. The deterministic version of this problem, the economic lot-scheduling problem, is the subject of a great deal of research. However, the problem with random demand for the products is commonly found in practice but is not as well researched. The models developed in this paper address the problem of dynamically planning the timing and size of production runs in this kind of production environment. We also report some computational results that indicate the quality of the resulting production schedules.  相似文献   
87.
Deregulation of the electricity industry aims for creating a competitive market to trade electricity, which generates a host of new technical challenges among market participants and power system researchers. One of the major challenges is to establish a cost for system services on a non-discriminatory basis. In this paper, the evaluation of transmission cost is proposed based on sensitivity factor method like AC Power Transfer Distribution Factor (ACPTDF) method for bilateral and multilateral transactions. The transacted power is estimated by ACPTDF method for each transaction. The advantages of the proposed methodology are demonstrated on a sample 6 bus, IEEE 30 bus and Indian Utility 69 bus systems. The solution provides a better pricing approach that can impact a more reasonable economic indicator for transmission cost.  相似文献   
88.
ABSTRACT

Previous flow visualizations and laser Doppler anemometer velocity measurements have shown that clean engine air filters are presented with very non-uniform velocity distributions when tested in the SAE universal panel Filter test housing. Experiments were conducted to measure the changes that occur in the velocity distribution in the plane 12.7 mm upstream of the filter as it is loaded with dust. Laser Doppler anemometer measurements of velocity profiles were performed for a production engine air Filter in the SAE universal panel filter test housing. Test conditions corresponded to a clean Filter, and dust-loaded Filters at additional pressure drops corresponding to 50 percent, 100 percent, and 150 percent of the design terminating pressure value. The results show that dust loading does make the velocity profiles less non-uniform, but that the changes are not dramatic. The inlet velocity profiles for the design capacity Filter remain very non-uniform.  相似文献   
89.
On many machine tools the set-up times are sequence dependent; that is, the time to set-up for the new part is dependent upon the part for -which the machine is currently set-up. In scheduling lots on the machine, the set-up time is often a significant component of the total time required to complete each lot. Set-up times are frequently not available to the production scheduler, and when they are, they frequently are only averages which conceal the sequence dependency of the set-up times. In this paper, we first develop a procedure that classifies set-up operations and predicts the set-up times and we then develop a method for sequencing the jobs so as to minimize the total set-up time. An example using real world data is used to illustrate these procedures  相似文献   
90.
The Helical Screw Rheometer (HSR) consists of a helical screw enclosed in a tight fitting cylinder. When the screw is rotated with the system closed it generates a linearly increasing pressure differential along the axis of the screw. The pressure is proportional to the viscosity of a Newtonian fluid. Viscosity of standard Newtonian fluids measured using the HSR correlated well with measurements on a rotational rheometer with cone and plate fixtures. HSR data on non-Newtonian suspensions analyzed with a power law model (σ= mγa) did not agree as well with results from cone and plate fiiures on the rotational rheometer.  相似文献   
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