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141.
142.
The objective of this study was to analyse the perception of the practical value of their training experience for 4 groups of alumni graduated between 1986 and 1989 at the Faculty of Odontology, University Paris 5. The 240 participants (45% response rate) perceived their training to have been adequate with respect to procedural activities. On the other hand, the graduates expressed a desire for more emphasis in emergencies, interpersonal relationship, office management and such clinical topics as fixed prosthodontics, surgery and periodontics. Surveys aimed at alumni may be useful for the evaluation of programme results and to determine which items should be added or deleted according to either health criteria or the conditions of dental practice.  相似文献   
143.
The iron storage protein bacterioferritin (BFR) consists of 24 identical subunits, each containing a dinuclear metal binding site called the ferroxidase center, which is essential for fast iron core formation. Cobalt(II) binding to wild-type and site-directed variants of Escherichia coli BFR was studied by optical and magnetic techniques. Data from absorption spectroscopy demonstrate the binding of two cobalt(II) ions per subunit of wild-type and heme-free BFR, each with a pseudotetrahedral or pentacoordinate geometry, and EPR studies show that the two cobalt(II) ions are weakly magnetically coupled. Studies of variants of BFR in which a single glutamic acid residue at the ferroxidase center is replaced by alanine confirm that this is the site of cobalt(II) binding, since the altered centers bind only one cobalt(II) ion. This work shows that the electroneutrality of the ferroxidase center is preserved on binding a pair of divalent metal ions. Optical and EPR data show that cobalt(II) binding to BFR exhibits positive cooperativity, with an average Kd of approximately 1 x 10(-5) M. The favored filling of the ferroxidase center with pairs of metal ions may have mechanistic implications for the iron(II) binding process. Discrimination against oxidation of single iron(II) ions avoids odd electron reduction products of oxygen.  相似文献   
144.
145.
Serum zinc was measured in 20 adolescent gymnasts (9 boys, 11 girls, age 12-15 yr) explored for detecting possible adverse effects of intense training on pubertal maturation and growth. They had low serum zinc (0.599 +/- 0.026 mg/L) when compared to matched control sedentary children (n = 118 mean 0.81 +/- 0.014 p < 0.001). Girls had lower zinc than boys (0.557 +/- 0.023 vs 0.651 +/- 0.044 p < 0.001). Zinc was correlated to isometric adductor strength (r = 0.468 p < 0.05). Children with serum zinc < 0.6 mg/L had lower insulin-like growth factor binding protein 3 than others (2.326 +/- 0.264 vs 2.699 +/- 0.12 p < 0.01). Thus, zinc is lowered in trained adolescent gymnasts and even lower in females. This reduction could play some role in abnormalities of puberty, growth, or muscular performance.  相似文献   
146.
To assess whether androgen excess per se might impair insulin action, insulin sensitivity was measured by a two-step (20 and 80 mU/m2.min) hyperinsulinemic euglycemic clamp combined with indirect calorimetry and tracer glucose infusion in 43 women (13 obese and 30 nonobese) with normal glucose tolerance and clinical evidence of increased androgen action (hirsutism and/or polycystic ovary syndrome) as well as 12 age- and body mass index-matched healthy controls. Hyperandrogenic women were studied basally and after 3-4 months of antiandrogen treatment with 3 different drugs: spironolactone (n = 23), flutamide (n = 10), or the GnRH agonist buserelin (n = 10). Six women given spironolactone were also reexamined after 1 yr of therapy. At baseline, insulin-mediated glucose uptake was lower in hyperandrogenic women than in controls (by ANOVA, F = 14.3; P < 0.001). Insulin resistance was observed in both ovarian and nonovarian hyperandrogenism, as distinguished by acute GnRH agonist testing. After antiandrogen therapy, insulin action on glucose metabolism significantly increased for both the patients as a whole (F = 7.4; P < 0.01) and each treatment group separately. However, insulin action remained lower than in controls and showed no further improvement in patients reevaluated after I yr of treatment. Increases in both oxidative and nonoxidative glucose metabolism accounted for the improvement in substrate disposal induced by antiandrogen drugs. The increase in the effectiveness of insulin was greater in the lean subjects, whereas the change was small and not statistically significant in the obese women. Response to treatment was more pronounced in women with nonovarian hyperandrogenism, particularly at the low insulin infusion rate. Endogenous glucose production in hyperandrogenic patients was similar to that in healthy women and was unaffected by therapy. In conclusion, antiandrogen treatment partially reversed the peripheral insulin resistance associated with hyperandrogenism regardless of which antiandrogen was used. These data strongly suggest that in women, androgen excess per se contributes to impairment of insulin action.  相似文献   
147.
This paper describes various new experiments fulfilled in order to reach a better understanding on the mechanisms by which the low stratosphere pollutants are transported up to a higher altitude.  相似文献   
148.
Conclusion Rapid heating in the production and final heat treatment of semiproducts made of titanium alloys can ensure a lamellar structure with stipulated size of -grains, refinement of the initial coarse-grained structure, various gradient structural compositons; all this is important in solving problems of improving the quality of semiproducts and enhancing the durability of parts made from them. Rapid heating can be effected with the use of molten salts, slags, liquid metals, electrocontact and induction devices.The main limitations in the use of such heating are connected with the dimensions and shape of the blanks and semiproducts, the most complex problems are due to the necessity of designing specialized equipment. Nevertheless, on account of the positive effect it is imperative to continue work on and to extend the fields of application of rapid heating in the production of semiproducts of titanium alloys.Translated from Metallovedenie i Termicheskaya Obrabotka Metallov, No. 12, pp. 33–37, December, 1991.  相似文献   
149.
A new stable version (“production version”) v5.28.00 of ROOT [1] has been published [2]. It features several major improvements in many areas, most noteworthy data storage performance as well as statistics and graphics features. Some of these improvements have already been predicted in the original publication Antcheva et al. (2009) [3]. This version will be maintained for at least 6 months; new minor revisions (“patch releases”) will be published [4] to solve problems reported with this version.

New version program summary

Program title: ROOTCatalogue identifier: AEFA_v2_0Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AEFA_v2_0.htmlProgram obtainable from: CPC Program Library, Queen?s University, Belfast, N. IrelandLicensing provisions: GNU Lesser Public License v.2.1No. of lines in distributed program, including test data, etc.: 2 934 693No. of bytes in distributed program, including test data, etc.: 1009Distribution format: tar.gzProgramming language: C++Computer: Intel i386, Intel x86-64, Motorola PPC, Sun Sparc, HP PA-RISCOperating system: GNU/Linux, Windows XP/Vista/7, Mac OS X, FreeBSD, OpenBSD, Solaris, HP-UX, AIXHas the code been vectorized or parallelized?: YesRAM: > 55 MbytesClassification: 4, 9, 11.9, 14Catalogue identifier of previous version: AEFA_v1_0Journal reference of previous version: Comput. Phys. Commun. 180 (2009) 2499Does the new version supersede the previous version?: YesNature of problem: Storage, analysis and visualization of scientific dataSolution method: Object store, wide range of analysis algorithms and visualization methodsReasons for new version: Added features and corrections of deficienciesSummary of revisions: The release notes at http://root.cern.ch/root/v528/Version528.news.html give a module-oriented overview of the changes in v5.28.00. Highlights include
  • • 
    File format Reading of TTrees has been improved dramatically with respect to CPU time (30%) and notably with respect to disk space.
  • • 
    Histograms A new TEfficiency class has been provided to handle the calculation of efficiencies and their uncertainties, TH2Poly for polygon-shaped bins (e.g. maps), TKDE for kernel density estimation, and TSVDUnfold for singular value decomposition.
  • • 
    Graphics Kerning is now supported in TLatex, PostScript and PDF; a table of contents can be added to PDF files. A new font provides italic symbols. A TPad containing GL can be stored in a binary (i.e. non-vector) image file; add support for full-scene anti-aliasing. Usability enhancements to EVE.
  • • 
    Math New interfaces for generating random number according to a given distribution, goodness of fit tests of unbinned data, binning multidimensional data, and several advanced statistical functions were added.
  • • 
    RooFit Introduction of HistFactory; major additions to RooStats.
  • • 
    TMVA Updated to version 4.1.0, adding e.g. the support for simultaneous classification of multiple output classes for several multivariate methods.
  • • 
    PROOF Many new features, adding to PROOF?s usability, plus improvements and fixes.
  • • 
    PyROOT Support of Python 3 has been added.
  • • 
    Tutorials Several new tutorials were provided for above new features (notably RooStats).
A detailed list of all the changes is available at http://root.cern.ch/root/htmldoc/examples/V5.Additional comments: For an up-to-date author list see: http://root.cern.ch/drupal/content/root-development-team and http://root.cern.ch/drupal/content/former-root-developers.The distribution file for this program is over 30 Mbytes and therefore is not delivered directly when download or E-mail is requested. Instead a html file giving details of how the program can be obtained is sent.Running time: Depending on the data size and complexity of analysis algorithms.References:
  • [1] 
    http://root.cern.ch.
  • [2] 
    http://root.cern.ch/drupal/content/production-version-528.
  • [3] 
    I. Antcheva, M. Ballintijn, B. Bellenot, M. Biskup, R. Brun, N. Buncic, Ph. Canal, D. Casadei, O. Couet, V. Fine, L. Franco, G. Ganis, A. Gheata, D. Gonzalez Maline, M. Goto, J. Iwaszkiewicz, A. Kreshuk, D. Marcos Segura, R. Maunder, L. Moneta, A. Naumann, E. Offermann, V. Onuchin, S. Panacek, F. Rademakers, P. Russo, M. Tadel, ROOT — A C++ framework for petabyte data storage, statistical analysis and visualization, Comput. Phys. Commun. 180 (2009) 2499.
  • [4] 
    http://root.cern.ch/drupal/content/root-version-v5-28-00-patch-release-notes.
  相似文献   
150.
Signing avatars are increasingly used as an interface for communication to the deaf community. In recent years, an emerging approach uses captured data to edit and generate sign language (SL) gestures. Thanks to motion editing operations (e.g., concatenation, mixing), this method offers the possibility to compose new utterances, thus facilitating the enrichment of the original corpus, enhancing the natural look of the animation, and promoting the avatar’s acceptability. However, designing such an editing system raises many questions. In particular, manipulating existing movements does not guarantee the semantic consistency of the reconstructed actions. A solution is to insert the human operator in a loop for constructing new utterances and to incorporate within the utterance’s structure constraints that are derived from linguistic patterns. This article discusses the main requirements for the whole pipeline design of interactive virtual signers, including: (1) the creation of corpora, (2) the needed resources for motion recording, (3) the annotation process as the heart of the SL editing process, (4) the building, indexing, and querying of a motion database, (5) the virtual avatar animation by editing and composing motion segments, and (6) the conception of a dedicated user interface according to user’ knowledge and abilities. Each step is illustrated by the authors’ recent work and results from the project Sign3D, i.e., an editing system of French Sign Language (LSF) content (http://sign3d.websourd.org/sltat).  相似文献   
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