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91.
Memory span was measured for lists of verbal items constructed such that the items in the 1st half of the list were of one category and those of the 2nd half were of another. In Exp 1, the lists consisted of digits and words (e.g., 2, 8, 77, horse, cow, sheep or horse, cow, sheep, 2, 8, 7); in Exp 2, they consisted of words from the same semantic domain and words from different semantic domains; in Exps 3 and 4, they consisted of words that rhymed and words that did not rhyme. A category-order effect occurred in each experiment: Span was larger when the digits, same-domain words, or rhyming words occurred in the 1st half of the list than when they occurred in the 2nd half. These findings suggest that memory span is more complex than is generally assumed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
92.
Measurement methods are being developed to provide values for the density, viscosity, heat capacity, enthalpy, fraction solid, surface tension, and thermal diffusivity and conductivity of commercial alloys in the liquid and mushy states. These data are needed for the mathematical modeling of heat and fluid flow in solidification processes. This paper briefly describes the present state of development of apparatus for the measurement of density by the levitated drop and hydrostatic probe methods and viscosity by the oscillating viscometer in our laboratory. Paper presented at the Fourth Asian Thermophysical Properties Conference, September 5–8, 1995, Tokyo, Japan.  相似文献   
93.
The CLAS forward electromagnetic calorimeter   总被引:1,自引:0,他引:1  
The CEBAF Large Acceptance Spectrometer (CLAS) at Jefferson Lab utilizes six iron-free superconducting coils to provide an approximately toroidal magnetic field. The six sectors are instrumented individually to form six independent spectrometers. The forward region (8°<θ<45°) of each sector is equipped with a lead–scintillator electromagnetic sampling calorimeter (EC), 16 radiation lengths thick, using a novel triangular geometry with stereo readout. With its good energy and position resolution, the EC is used to provide the primary electron trigger for CLAS. It is also used to reject pions, reconstruct π° and η decays and detect neutrons. This paper treats the design, construction and performance of the calorimeter.  相似文献   
94.
95.
In Experiment 1, 12 lactating Holstein cows were provided drinking water of either 10.6 or 27.0 degrees C for 24 h/d in a changeover design to examine the effects of water temperature on feed intake, water intake, respiration rate, rectal temperature, plasma thyroid hormone concentration, and milk yield. The 1st wk of each 3-wk treatment period was for adjustment and the next 2 wk were comparison periods. Least squares means for DM intake as a percentage of body weight were 3.68 and 3.57 for 10.6 and 27.0 degrees C treatment groups. Water intakes in liters per kilogram of dry feed consumed as a percentage of body weight were 21.3 and 20.3. Respiration rates were 70.5 and 81.0 breaths per minute; rectal temperatures were 39.7 and 39.9 degrees C, Triiodothyronine averaged .88 and .75 ng/ml; thyroxine, 42.4 and 39.2 ng/ml; cortisol, 3.03 and 2.06 ng/ml; and progesterone in milk, 4.58 and 3.15 ng/ml for the 10.6 and 27.0 degrees C treatment groups. Milk yield averaged 25.9 and 24.7 kg/d and FCM averaged 25.6 and 23.6 kg/d, respectively. In Experiment 2, 24 cows given a choice of chilled or warm water showed a clear preference (about 98%) for the warm water. If cows are given chilled water of 10 degrees C continuously, no warm drinking water should be available. Chilled drinking water lowered respiration rates and body temperatures and increased feed intake and milk yield.  相似文献   
96.
The vast majority of polymers used in modern prosthetic dentistry are acrylic. They may be homopolymers or copolymers. A technique is described which involves the pyrolysis (thermal degradation) and subsequent analysis by gas chromatography of these polymers. Sample introduction is by means of a ferromagnetic wire which supports a film of the polymer obtained from a solution of the polymer in chloroform. Quantitative determinations can be achieved with the use of relevant standard copolymer compositions.  相似文献   
97.
This paper reports the combination of Holographic Mapping (HM) and Artificial Neural Networks (ANNs) in order to provide a benchmark visualization of a multi-dimensional space in two-dimensional forms. In this approach each matrix point in HM represents virtual catalytic data generated by means of ANNs in order to visualize the given multi-dimensional experimental space. A 12-dimensional experimental space related to the composition of catalysts designed for the water gas shift reaction (WGSR) from 12 possible components supported on ZrO2 is visualized. Catalytic data obtained in an earlier combinatorial screening process at 300 °C were used for training of the ANNs. The results show that the visualization of large experimental spaces having more than half a million virtual experimental points can be accomplished. The analysis of synergistic effects between different components revealed that the key components of water gas shift catalysts at 300 °C were Pt, Fe, Eu and V, while Co, Ru, Sb, Ge and Mo had a pronounced negative effect on the activity.  相似文献   
98.
A potentially Listeria-specific 28 base oligonucleotide probe was designed from 16S rRNA sequence data. Using either 32P or non-radioactive (alkaline phosphatase) labels, the probe was shown to be highly specific as it hybridised to RNA extracted from all of the species of Listeria but not to any of the other bacteria tested. Both probe methods were highly sensitive and ca 10(2) cfu/ml Listeria could be detected in pure cultures. A rapid procedure for extracting RNA from milk, Camembert and cottage cheese was developed. This allowed the direct application of the probe to these foods and gave a rapid and specific method of detecting > 10(2) cfu/g or ml Listeria in these foods.  相似文献   
99.
Comments on the argument of L. T. Hoshmand and D. E. Polkinghorn (see record 1992-21300-001) that psychological practice should inform science to the same degree that science informs practice. Based on a survey of 121 faculty members in programs accredited by the American Psychological Association, 65% reported practice activity. The authors agree that the problem involves a much more complex integrative task that goes beyond simply recognizing knowledge gained in practice settings as valid. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
100.
In this study a MADYMO (mathematical dynamic modelling) model has been used to identify the influence of leg fracture on the injuries sustained by the pedestrian during front end impact with a vehicle. A factorial study of a MADYMO pedestrian and vehicle model are used to investigate the effect of different leg fracture tolerances, geometry, and vehicle compliance on the criteria measured in the European Enhanced Vehicle-safety Committee (EEVC) pedestrian safety tests. These criteria include knee bending, knee shear response, and lower leg bone (tibia) acceleration. The main study examines the spread of typical values of lower limb tolerance based on reported literature and contrasts the response of weaker, low-strength bones, normal tolerance, and limbs which do not fracture. Results show that knee bending angles and therefore ligament strains are significantly increased when fracture does not occur, and are decreased in bones exhibiting a low-strength response. Bone fracture tolerance is shown to be a significant parameter influencing knee bending. The parameters are compared to show that knee shear is significantly influenced by vehicle bumper compliance and that both criteria are heavily influenced by bumper height. Vehicles with more aggressive geometry, higher bumpers, and larger bumper lead were considered for comparative purposes.  相似文献   
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