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181.
The complexation of poly(pyridylthioether) incorporating a Fe2(CO)6 cluster core with palladium derivatives in different oxidation states afforded novel hetero-polymetallic complexes.  相似文献   
182.
183.
OBJECTIVE: To assess the influence of passive and light active smoking on the reduction of intrauterine growth of the foetus and on modifications in the body composition of the newborn. DESIGN: Random. SETTING: Full term newborn infants at the Department of the Pediatric and Gynaecological Divisions of the City Major Hospital, Chair of Paediatrics, Verona University. SUBJECTS: One hundred and twelve mothers selected after having completed a questionnaire on smoking habits during pregnancy. One hundred and twelve newborn infants were divided into three groups: Group 1: non-smoking and non-exposed mothers; Group 2: non-smoking but exposed mothers; Group 3: light smoking mothers (under 10 cigarettes/d, whether or not also exposed to passive smoking). Examination within 24 h of birth established the anthropometric measurements and estimates of body composition through indices or equations. RESULTS: Newborns of groups 2 and 3 had a statistically significant reduction of fat mass and most anthropometric measurements: fat mass according to Dauncey (P < 0.001), birth-weight (P < 0.013), crownheel length (P < 0.000), upper- and lower-arm length (P < 0.000) and circumference (P < 0.002), triceps skinfold and sum of all skinfolds (P < 0.004). Student t-test, between groups 2 and 3, did not evidence intergroup differences. CONCLUSIONS: Exposure of the foetus to passive and/or light active smoking involves a reduction of most auxiological parameters and not only weight. As regards body composition, smoking appears to reduce fat mass. The prevention of smoking during pregnancy is therefore extremely important, as intrauterine growth seems to be negatively influenced not only by active smoking, but also by passive and light active smoking.  相似文献   
184.
This letter presents a binary Hough transform (BHT) derived from the conventional Hough transform with slope/ intercept parameterization and a systolic architecture for its efficient implementation using only adders and delay-elements.  相似文献   
185.
Targets of this work have been: testing of duplex stainless steel in field (into a geothermal well) and in laboratory NACE environment in presence of crevices and sharp defects; development of testing based on fracture mechanics and comparsion with traditional testing approach. The following types of specimens have been used: smooth specimens for tensile tests at constant load with artificial crevices, U-bend specimens and 1/2″ WOL-modified fracture mechanics specimens. The results are only in partial accordance with available literature data and suggest to be very careful in extending laboratory results to real conditions, where, for instance, crevices and sharp defects always exist.  相似文献   
186.
The present work aimed at studying risk factor that affect people with back pain, identifying them and implementing an intervention proposal of a health education program based on self-care teaching, existential humanist philosophical projects and stress equalization approach line, skeletal-muscle reintegration activities, basic techniques on stress equalization and massage. It has been developed for a population of 42 (forty-two) clients. Two instruments which integrate nursing consultation protocol have been used in data collection. The results showed the existence of associated risk factors which are changeable according to health education programs. The assessment process has contributed for therapeutic measures focus, using non-conventional care methods for this approach providing an improvement to these clients life quality.  相似文献   
187.
Contextualizing ontologies   总被引:2,自引:0,他引:2  
Ontologies are shared models of a domain that encode a view which is common to a set of different parties. Contexts are local models that encode a party’s subjective view of a domain. In this paper, we show how ontologies can be contextualized, thus acquiring certain useful properties that a pure shared approach cannot provide. We say that an ontology is contextualized or, also, that it is a contextual ontology, when its contents are kept local, and therefore not shared with other ontologies, and mapped with the contents of other ontologies via explicit (context) mappings. The result is Context OWL (C-OWL), a language whose syntax and semantics have been obtained by extending the OWL syntax and semantics to allow for the representation of contextual ontologies.  相似文献   
188.
A simple two-node axisymmetric shell element with shallowly curved meridian assumptions and the inclusion of shear deformation and rotary inertia is presented. The principal developments include: (a) consistent resolution of the membrane and shear related excessive stiffening (locking) via anisoparametric interpolations of the displacement variables; (b) further upgrading of strain energy by means of a shear relaxation (correction) parameter. The resulting element possesses an improved condition of the stiffness matrix, increased efficiency in explicit time integration and enhanced accuracy in coarse discretizations. Comprehensive vibration examples are carried out to assess the element performance. The numerical results demonstrate a wide applicability range with respect to element slenderness and curvature properties.  相似文献   
189.
A dinuclear gadolinium(III) chelate containing two moieties of diethylenetriaminepentaacetic acid (DTPA), covalently conjugated to an analogue of deoxycholic acid, was synthesized and thoroughly characterized. A full relaxometric analysis was carried out, consisting of 1) the acquisition of nuclear magnetic resonance dispersion (NMRD) profiles in various media; 2) the study of binding affinity to serum albumin; 3) the measurement of 17O transverse relaxation rate versus temperature, and 4) a transmetallation assay. In vivo biodistribution MRI studies at 1 T and blood pharmacokinetics assays were carried out in comparison with Gd‐DTPA (Magnevist) and gadocoletic acid trisodium salt (B22956/1), two well‐known Gd complexes that share the same chelating cage and the same deoxycholic acid residue of the Gd complex investigated herein ((GdDTPA)2‐Chol). High affinity for plasma protein and, in particular, the availability of more than one binding site, allows the complex to reach a fairly high relaxivity value in plasma (~20 mm ?1 s?1, 20 MHz, 310 K) as well as to show unexpectedly enhanced properties of blood pooling, with an elimination half‐life in rats approximately seven times longer than that of B22956/1.  相似文献   
190.
This paper presents PLCTOOLS, a formal environment for designing and simulating programmable controllers. Control models are specified with IEC FED (Function Block Diagram), and translated into functionally equivalent HLTPNs (High-Level Timed Petri Nets), through MetaEnv, for analysis and simulation and obtained results are presented in terms of suitable animations of FED blocks.The peculiarity with FBD is that it does not come with a fixed set of syntactic elements; it allows users to add as many new blocks as they want. Consequently, each time users want to add a new FBD block with PLCTOOLS, they must provide the concrete syntax, to add it to the library of available blocks, but also the associated HLTPN, to allow MetaEnv to build the formal representation.  相似文献   
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