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101.
102.
The authenticity of 91 wines produced in Cyprus from both indigenous and other vine varieties were investigated by a holistic approach, using, advanced technology such as SNIF-NMR (site-specific natural isotopic fractionation-nuclear magnetic resonance) and 1R-MS (isotope ratio-mass spectrometry) for the determination of the stable isotopes and ICP (inductively coupled plasma spectroscopy) for some heavy metals. The spectroscopic characteristics were evaluated statistically using different chemometric methods. The dependency of the D/H (deuterium/hydrogen) ratio of the methylene site in the ethanol molecule (D/H)ll and also theδ ^18O values of the wine water, were the most useful discriminators. Isotopic results allow us to have a complete idea about the regional variability of the isotopes. Among the metals, Ni followed by Pb was the ones with the highest discrimination value. The determined concentrations of Pb, Ni, Cr and Cd that are related to the safety of wines were within the acceptable limits that have been established by the OIV (international organization of vine and wine) or comparable with the results of the wines of other European countries. The study of the correlation between the load of heavy metals and isotopes in wines showed a dependence on the grape variety but not the geographical location of the vineyard. This is probably due to the close proximity of wine regions in Cyprus.  相似文献   
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UMLDiff is a heuristic algorithm for automatically detecting the changes that the logical design of an object-oriented software system has gone through, as the subject system evolved from one version to the next. UMLDiff requires as input two models of the logical design of the system, corresponding to two of its versions. It produces as output a set of change facts, reporting the differences between the two logical-design versions in terms of (a) additions, removals, moves, renamings of model elements, i.e., subsystems, packages, classes, interfaces, attributes and operations, (b) changes to their attributes, and (c) changes to the relations among these model elements. In this paper, we detail the underlying metamodel, the UMLDiff algorithm and its heuristics for establishing lexical and structural similarity. We report on our experimental evaluation of the correctness and robustness of UMLDiff through a real-world case study.  相似文献   
105.
This paper provides evidence that it is possible to migrate structured system designs to UML models. Legacy structured designs can be converted to object-oriented systems without losing data or functionality. The reason for choosing UML is that it is the new standard notation, which tries to build on and integrate object-oriented notations. Extracts from a case study are presented together with the proposed guidelines for the re-engineering process.  相似文献   
106.
The application of fluorescence confocal laser scanning microscopy (CLSM) to quantify three-dimensional pH gradients near electrode surfaces is described. The methodology utilizes a trace quantity of a fluorescent dye, fluorescein, in solution, which fluoresces strongly above pH 6.5, to map the pH adjacent to various ultramicroelectrodes undergoing electrochemical processes that lead to pH changes. The experimental fluorescence profiles, determined by CLSM, have been compared to models by solving the underlying mass transport equations, including the effect of natural convection, using the finite element method. The methodology has been validated through studies of the galvanostatic reduction of water at both disk and ring ultramicroelectrodes. The fluorescence profiles were found to be highly sensitive to both the initial bulk solution pH and applied current in a predictable fashion. The potentiostatic reduction of oxygen has been investigated at 25- and 10-microm-diameter platinum electrodes to confirm the effective number of electrons transferred in the reaction. Finally, the application of this methodology to observe defects in microelectrode arrays, particularly those that cannot be seen by optical microscopy, is described.  相似文献   
107.
Electrospray ionization (ESI) is extensively used in the analysis of biological compounds; yet some fundamental properties of this technique are not completely understood. It is widely recognized that care should be exercised when noncovalent complexes are being studied by ESI, since weak noncovalent binding can be broken or formed during the desolvation process. In the present work, spectra from the noncovalent complex, vancomycin/diacetyl-L-lysyl-D-alanyl-D-alanine, obtained from ESI and from nanoelectrospray ionization (nanoESI), have been compared. The results indicated that the milder desolvation conditions arising as a result of the smaller sizes of droplets produced in the nanoESI source attenuated effects upon weak bonds in the desolvation process. The association constant values calculated from the relative peak intensities suggest that, when using ESI, the analyzed noncovalent complex dissociated in the condensed phase during the spraying process. The influences of experimental parameters such as tip diameter and coating for nanoESI needles were investigated. Principal component analysis, a multivariate analysis method, was applied to achieve a better evaluation of the spectra obtained using different needle diameters and coatings for the analysis of the noncovalent complex vancomycin/diacetyl-L-lysyl-D-alanyl-D-alanine. It was found that 2-microm tip diameter resulted in more reproducible spectra than the larger tip diameters tested (6-20 microm).  相似文献   
108.
The aims of this work were to examine the attitudes of individuals with visual impairments towards distance education (DE) and the relationships between attitudes and participants’ personal characteristics. Forty-one adults with visual impairments, who ranged in age from 20 to 40, participated in this study. A self-constructed questionnaire measuring the attitudes towards DE was employed. The participants’ answers revealed slightly positive emotions towards DE according to the affective component of attitudes, slightly positive attitudes when DE is compared with traditional education, and positive attitudes as far as the cognitive component of attitudes and participants’ intention to participate in a DE programme were concerned. The elder participants seem to have more positive attitudes towards DE compared with younger participants. Furthermore, the greater the level of education, the more positive were the attitudes towards DE, and the greater the frequency of computer usage, the more positive were the attitudes towards DE. The analysis of the data collected revealed that the sample of individuals with visual impairments had slightly positive attitudes towards DE. Age, level of education, and frequency of computer usage were found to be significant predictors of the participants’ attitudes.  相似文献   
109.
The purpose of this work is the study of surface characteristics of four dental light-cured dimethacrylate-based resin nanocomposites after immersion in water or an ethanol/water solution, using scanning electron microscopy and atomic force microscopy. Water and ethanol treatment affected the morphology and component distribution on the surface of samples. Scanning electron microscopy revealed changes on a large scale in the surface morphology of treated samples caused by immersion in water while the ethanol/water solution treatment influenced sample integrity too. It was proven that the use of atomic force microscopy in the phase-imaging mode is crucial in revealing subtle changes in component distribution on the polymer composite surface which are not accompanied by significant morphological changes.  相似文献   
110.
The increased operational tempo associated with current deployments to Operation Iraqi Freedom (OIF) and Operation Enduring Freedom (OEF) is placing considerable strain on military families. Among other sequelae of OIF and OEF deployment, findings from recent studies suggest high rates of depression in spouses of service members. This review presents a rationale for targeting depression among military spouses. It examines how stressors relating to the deployment cycle may contribute to depression in spouses and outlines the effects of spousal depression on the mental health of service members and their children. Mental health services currently available to military spouses as well as barriers to their care are also described. Considerations for the adaptation of treatment to their unique circumstances and needs are discussed. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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