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101.
Aggregation pheromones were isolated fromCryptolestes pusillus (Schönherr), a coleopteran pest of stored products. Porapak Q-captured beetle and frass volatiles were fractionated by preparative gas-liquid chromatography. The fractions were bioassayed with an arena olfactometer and/or with a two-choice, pitfall olfactometer. Three biologically active, male-produced compounds eliciting aggregation behavior from adultC. pusillus were isolated and identified by spectroscopic methods as (Z)-3-dodecenolide (I), (Z)-5-tetradecen-13-olide (II), and (Z,Z)-3,6-dodecadienolide (III). Compound I was the major volatile produced and was active alone. Compound II was not active alone, but synergized the response to I. Compound III was active alone at higher concentrations, but did not significantly increase the response when added to the most active mixture of I and II, and so it is probably not part of the aggregation pheromone. Pheromone production increased dramatically when the insects were aerated on a food source.Research supported in part by the Natural Sciences and Engineering Research Council of Canada, Operating Grants A3881 and A3785, Strategic Grant 60958, and a Graduate Scholarship to J. G. Millar.  相似文献   
102.
Biodegradation of 1,4-Dioxane Using Trickling Filter   总被引:1,自引:0,他引:1  
The ability of a laboratory-scale trickling filter to biodegrade cyclic ethers was investigated and a simple kinetic model was developed to predict ether biodegradation. The trickling filter received a feed solution designed to mimic ether concentrations typically encountered in contaminated groundwater. The reactor was operated for approximately 1 year and was capable of biodegrading 93–97% of 1,4-dioxane at various loading rates in the obligate presence of tetrahydrofuran (THF) as the growth substrate. A simple tanks-in-series hydraulic model combined with a kinetic model that incorporated cometabolism was utilized to simulate removal of THF and 1,4-dioxane. Model simulations of THF removal were satisfactory for all loading rates analyzed. However, the model somewhat over predicted 1,4-dioxane removal. This research demonstrates the ability to treat groundwater contaminated with low concentrations of ethers in attached growth reactors.  相似文献   
103.
The introduction of robots into any organization forms part of a considerable investment in new technology over a range of applications in the search for efficiency and increased productivity. The greater consistency and quality associated with robot operations, compared with that of the human operator, is regarded as an advantage both in relation to the manufacturing process and to the product. However, in order to make the most efficient use of robots, the ability to generate good robot programs must be developed. Traditional robot programming techniques are extremely slow and laborious. Off-line programming by textual input alone is an equally tedious process. In this paper, existing and potential problems associated with off-line programming are examined. Various commercial and experimental robot languages and their relative important features are described. Opinions of manufacturers of CNC (Computer Numerically Controlled) machines and robots concerning both user interfaces and potential candidate users are discussed. Both the training and the abilities of the candidate robot programmers are important aspects of any robot programming system, although obviously much will depend on the sophistication of the particular application. Recommendations are made concerning issues that should be taken into account when developing future off-line programming systems.  相似文献   
104.
105.
Small radar detection and tracking systems, in particular radar guided missile systems, are of great utility because of their all-weather performance and their long range capabilities. A major drawback with these systems results from the relatively simple data that they collect and the difficulty in using these data for target classification and identification purposes. The authors examine a technique which employs the statistics of the tracking data used by many missile seekers and which creates a cross-range target structure map that can be expressed as a function of the target's down-range extent. These data consist of ordinary azimuth-elevation angle-of-arrival measurements collected from a small set of (unknown) aspects presented by the target as it maneuvers. The method requires a minimal computational burden and may hold the potential to be used for automatic (machine-based) target classification in realistic (time and data limited) environments  相似文献   
106.
107.
An analysis is presented to predict the strength of glass after subsurface cracking is produced by drawing a lightly loaded angular particle across the surface. It is shown that the presence of subsurface cracks combined with the residual stresses introduced by such scratches under very small loads greatly lowers the strength of glass. The predicted ranges of tensile strength for soda–lime glass in dry and moist environments are in agreement with typical values in the literature.  相似文献   
108.
We establish the existence of liftings into discrete subspaces of \(\varvec{H}({{\mathrm{div}}})\) of piecewise polynomial data on locally refined simplicial partitions of polygonal/polyhedral domains. Our liftings are robust with respect to the polynomial degree. This result has important applications in the a posteriori error analysis of parabolic problems, where it permits the removal of so-called transition conditions that link two consecutive meshes. It can also be used in the a posteriori error analysis of elliptic problems, where it allows the treatment of meshes with arbitrary numbers of hanging nodes between elements. We present a constructive proof based on the a posteriori error analysis of an auxiliary elliptic problem with \(H^{-1}\) source terms, thereby yielding results of independent interest. In particular, for such problems, we obtain guaranteed upper bounds on the error along with polynomial-degree robust local efficiency of the estimators.  相似文献   
109.
Image‐based lighting has allowed the creation of photo‐realistic computer‐generated content. However, it requires the accurate capture of the illumination conditions, a task neither easy nor intuitive, especially to the average digital photography enthusiast. This paper presents an approach to directly estimate an HDR light probe from a single LDR photograph, shot outdoors with a consumer camera, without specialized calibration targets or equipment. Our insight is to use a person's face as an outdoor light probe. To estimate HDR light probes from LDR faces we use an inverse rendering approach which employs data‐driven priors to guide the estimation of realistic, HDR lighting. We build compact, realistic representations of outdoor lighting both parametrically and in a data‐driven way, by training a deep convolutional autoencoder on a large dataset of HDR sky environment maps. Our approach can recover high‐frequency, extremely high dynamic range lighting environments. For quantitative evaluation of lighting estimation accuracy and relighting accuracy, we also contribute a new database of face photographs with corresponding HDR light probes. We show that relighting objects with HDR light probes estimated by our method yields realistic results in a wide variety of settings.  相似文献   
110.
The use of intravenous procaine in the treatment of hyperpyrexia in a patient with hyperparathyroidism has not been previously reported. A case of metastatic malignant melanoma precipitating the syndrome of hypertonicity of muscle, hyperpyrexia, acidemia, hypercalcemia and elevated serum parathormone levels is presented. Mithramycin was used in an attempt to reduce elevated serum calcium concentrations. The use of intravenous procaine in "caffeine rigor" and malignant hyperthermia due to succinylcholine and halothane formed the basis for its trial in this case. The relationship between cyclic AMP and calcium ions is discussed in postulating mechanism of procaine action.  相似文献   
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