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181.
A mathematical model able to deal with high temperature gas effects in hypersonic flow fields is presented. In order to assess this model, four typical hypersonic applications are considered. The numerical results are presented and compared with experimental data. The effects of the catalyticity of the materials on the heat fluxes are also highlighted. 相似文献
182.
Erasmo Viola Claudia Belmonte Giuseppe Viola 《International Journal of Fracture》2009,157(1-2):175-192
In this paper the elastostatic solution of an inclined crack problem has been analyzed. The approach is analogous to the one proposed over the past years for orthotropic materials by Piva andViola (1988) (Eng Fract Mech, 29: 535–548), and it may be considered an alternative to the mathematical formalisms currently used. A general expression of the stress field is determined in terms of complex potentials. The stress distribution and the displacement field in the proximity of the crack tip are finally obtained. An expression of the energy release rate is provided in terms of the field intensity factors. Numerical results are presented and discussed under different remote electro-mechanical loading conditions and varying the crack inclination. Particular attention has been focused on the effect of the lateral load on the fracture quantities and on the direction of the incipient branching angle. 相似文献
183.
The paper is the introduction to the special issue Water Engineering and Management in a Changing Environment which presents a set of the most innovative contributions at the EWRA Symposium, held in Catania, Italy on 2011. 相似文献
184.
185.
Giuseppe Genova Patrizia Iacopini Massimiliano Baldi Annamaria Ranieri Paolo Storchi Luca Sebastiani 《International Journal of Food Science & Technology》2012,47(1):13-23
The effect of temperature and storage time on the phenolic composition and on the antioxidant activity of grape (Vitis vinifera L.) juices made using a red (Sangiovese, SG) and a white (Muscat of Alexandria, MA) variety was studied. Total phenolics, flavonoids, flavan‐3‐ols and hydroxycinnamoyl‐tartrates (HCT) were determined on grape extracts (GE) and juices. Total anthocyanins and anthocyanins composition were measured on GE. The antioxidant activity was assessed by means of two different in vitro tests: scavenging of the stable 2,2‐diphenyl‐1‐picrylhydrazyl radical and the inhibition of tyrosine nitration mediated by authentic peroxynitrite (ONOO?). All the juices were analysed after 24 h and 2 weeks of storage by means of two‐way anova (factors being cultivar and temperature). Anthocyanins were not detected in MA extract, whereas in SG their content was 534 mg malvidin‐equivalent per 100 g of dry matter (d.m.) and malvidin derivatives (glycosylated and coumaroylated) were the most represented (respectively 169 and 41 malvidin‐equivalent per 100 g of d.m.). HCT content of the extracts was higher in SG (overall +33%). Also in grape juices, HCT were lower in MA and in this variety, the trans‐fertaric and cis‐coutaric acids were also undetectable. Cultivar effect proved to be highly significant, while no significant differences in the phenolic composition were observed for storage temperatures (4 and ?20 °C) and cultivar × temperature interaction. However, when statistical analysis was focused on each cultivar, MA was found to be more sensible to storage conditions and a significant reduction in total phenolics (?20%) and flavonoids (?53%) content and in the ONOO? scavenging potential (?32%) was evident after 2 weeks at 4 °C (when compared with the same storage temperature after 24 h). On the contrary, SG juices did not show significant differences among the four storage treatments investigated. These results could be explained suggesting that anthocyanins presence in red grape plays a key role in juice stability. 相似文献
186.
Giada La Scalia Giuseppe Aiello Cristiana Rastellini Rosa Micale Luca Cicalese 《Expert systems with applications》2011,38(4):3091-3097
Pancreatic islet transplantation consists of replacing insulin-producing cells to restore normal glycemia in diabetic patients. This is a minimal invasive procedure that has been proved successful. Unfortunately unpredictability of islet transplant outcome remains a frustrating and costly issue limiting the clinical implementation of this procedure. Multiple variables are involved in the procedure and assessment is subjective to individual operators. The aim of this study was to generate a system expressing the probability of transplant success in relation to four classes of identified variables (donor, organ, isolation and recipient). We have proposed the utilization of Multi-Criteria Decision Making methods (MCDM) as a powerful tool for evaluating pancreatic islet transplant-related information with the goal to achieve optimal decision. Technique Ordered Preference by Similarity to the Ideal Solution (TOPSIS), one of the most widely used MCDM methods in decision support systems, was here utilized with modification to fit better in a medical system. In our modified method, we have utilized fuzzy logic in order to consider uncertain and vague data. 相似文献
187.
We show three linear-time algorithms for constructing planar straight-line grid drawings of outerplanar graphs. The first
and the second algorithm are for balanced outerplanar graphs. Both require linear area. The drawings produced by the first
algorithm are not outerplanar while those produced by the second algorithm are. On the other hand, the first algorithm constructs
drawings with better angular resolution. The third algorithm constructs outerplanar drawings of general outerplanar graphs
with O(n
1.48) area. Further, we study the interplay between the area requirements of the drawings of an outerplanar graph and the area
requirements of a special class of drawings of its dual tree.
Work partially supported by MUR under Project MAINSTREAM Algorithms for Massive Information Structures and Data Streams. 相似文献
188.
Parts 1 and 2 of this work outlined the background and the general terms of assuring compliance of food contact materials (FCM) with European legislation by good manufacturing practice (GMP) and compliance declaration (CD). All stages of the manufacturing process are engaged in GMP defined as the process to achieve compliance of the final product with Article 3 of the Framework Regulation 1935/2004 and the specific legislation derived there from. For each relevant aspect, either compliance is concluded (explicitly stating compliance if this is required) or compliance work is delegated to later stages of manufacturing by corresponding instructions in the documentation accompanying the product. A compliance box (CB) is proposed to structure the process and the documentation. Here it is applied to metal closures for glass jars, which are internally coated and contain a gasket of plasticized PVC. A specific composition is assumed and possible compliance work discussed to illustrate how the system is conceived. The system is tested by the problems and issues concerning these lids during the last 10 years: indeed, most of them would have been avoided. 相似文献
189.
Detection and recognition of the level of congestion at an intersection is a very important problem and a valuable source of information in traffic management. Although it is just one of all the aspects that make up a traffic management system, it seems to be a crucial point for gathering information. In this paper, we present a technique based on a k-means clustering algorithm for classification, which has been already successfully used in a number of pattern recognition problems, namely: as an algorithm for face recognition problems and in a number of medical diagnosis problems and it compares very well with the state of the art techniques. 相似文献
190.