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991.
The anodic behavior of gold has been investigated in presence of chloride and/or water in 1-butyl-3-methylimidazolium methanesulfonate (BMI CH3SO3) ionic liquid (IL). The cyclic voltammetry (CVs) in presence of chloride ions shows two waves attributed to the oxidation of the gold electrode which occurs under two steps: the first one is attributed to the electrochemical dissolution of gold into to gold(I), while the second one is attributed to an overlap of the chloride oxidation step as well as the oxidation of Au(I) to Au(III). Furthermore the determination of water and chloride content in IL allowed observing that the passive layer induced by water could be removed under chloride. Thanks to those results we were able to clarify the conditions of gold recovering in this kind of electrolyte. 相似文献
992.
Geffken Gary R.; Lehmkuhl Heather; Walker Kelly N.; Storch Eric A.; Heidgerken Amanda D.; Lewin Adam; Williams Laura B.; Silverstein Janet 《Canadian Metallurgical Quarterly》2008,53(2):231
Purpose/Objective: To examine relations between episodes of diabetic ketoacidosis (DKA) and parental warmth, parental negativity, and lack of responsibility for diabetes-related tasks in a sample of youths with Type 1 diabetes (T1D). Research Method/Design: 100 youths with T1D and their caregivers, recruited from an inpatient diabetes unit and an outpatient diabetes clinic, participated. Participants completed disease-specific measures of family functioning (e.g., parental warmth, parent and child perceptions of negativity, family responsibility for diabetes regimen), and medical information (e.g., glycosylated hemoglobin and incidences of DKA) was obtained from medical records. Results: Results showed that higher child perceptions of parental warmth and caring related to the regimen were associated with decreased odds of experiencing a DKA episode. Child reports of higher parental negativity about the regimen were associated with increased odds of experiencing a DKA episode. Reports of who in the family was responsible for the diabetes regimen were not related to episodes of DKA. Conclusions/Implications: Findings suggested that family factors play a significant role in the occurrence or absence of DKA in children's long-term management of diabetes. Future intervention efforts should focus on warmth, caring, and negativity when children and their parents are problem solving and communicating about the diabetes regimen. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
993.
Kate Dunning Adeline Martz Francisco Andrs Peralta Federico Cevoli Eric Bou-Grabot Vincent Compan Fanny Gautherat Patrick Wolf Thierry Chataigneau Thomas Grutter 《International journal of molecular sciences》2021,22(12)
P2X7 receptors (P2X7) are cationic channels involved in many diseases. Following their activation by extracellular ATP, distinct signaling pathways are triggered, which lead to various physiological responses such as the secretion of pro-inflammatory cytokines or the modulation of cell death. P2X7 also exhibit unique behaviors, such as “macropore” formation, which corresponds to enhanced large molecule cell membrane permeability and current facilitation, which is caused by prolonged activation. These two phenomena have often been confounded but, thus far, no clear mechanisms have been resolved. Here, by combining different approaches including whole-cell and single-channel recordings, pharmacological and biochemical assays, CRISPR/Cas9 technology and cell imaging, we provide evidence that current facilitation and macropore formation involve functional complexes comprised of P2X7 and TMEM16, a family of Ca2+-activated ion channel/scramblases. We found that current facilitation results in an increase of functional complex-embedded P2X7 open probability, a result that is recapitulated by plasma membrane cholesterol depletion. We further show that macropore formation entails two distinct large molecule permeation components, one of which requires functional complexes featuring TMEM16F subtype, the other likely being direct permeation through the P2X7 pore itself. Such functional complexes can be considered to represent a regulatory hub that may orchestrate distinct P2X7 functionalities. 相似文献
994.
Eric J.E. Molin Harmen Oppewal Harry J.P. Timmermans 《Journal of Housing and the Built Environment》2001,16(3-4):267-284
Conjoint estimates of residential preferencesare typically based on aggregate responses. Forreasons of segmentation or to differentiatebetween non-significant housing attributes andattributes that are characterized byconflicting preferences, further analysis isrequired. In this paper, the heterogeneity inthe conjoint estimates of residentialpreferences of families is analyzed. It isexamined how the estimated part-worth utilitiesof the housing attributes are related to thesocio-economic variables and current housingattributes by applying regression analysis.Although the explained variance was rather low,suggesting that residential preferences offamilies are highly idiosyncratic, therelationships that were significant could beinterpreted well. 相似文献
995.
Geert Jan Thijssen Dingena L. Schott Ernst W. Demmink Gabriel Lodewijks 《Energy Efficiency》2011,4(2):223-233
In the field of bulk solids, handling knowledge on moisture behaviour in aggregate stockpiles can be useful for process optimisation
in terms of energy consumption. In the asphalt industry, an increase in moisture content leads to a significant increase in
energy consumption. To determine the characteristics of moisture behaviour, correlations are investigated between theory on
soil–water movements and moisture in aggregates. With column drainage experiments with porous bottom, similarities between
theory and practice are found. This allows the use of theoretical hydrologic models to determine and predict the moisture
behaviour in drained piles. The effect of process alterations within the system of piles on energy consumption was investigated,
and a significant reduction of energy consumption was found. 相似文献
996.
Boutelle Kerri N.; Hannan Peter; Fulkerson Jayne A.; Crow Scott J.; Stice Eric 《Canadian Metallurgical Quarterly》2010,29(3):293
Objective: Both obesity and depression are prominent during adolescence, and it is possible that obesity is a trigger for adolescent depression. The purpose of this paper is to evaluate whether overweight or obese status contributes to the development of depression in adolescent girls. Design: Participants were 496 adolescent girls who completed interview based measures of depression and had their height and weight measured at four yearly assessments. Repeated measures logistic regressions with generalized estimating equations were used to evaluate whether overweight or obese status were associated with major depression or an increase in depressive symptoms the following year. Main Outcome Measures: Major depression and depressive symptoms were evaluating using a modified version of the K-SADS interview. Overweight and obese status was determined by using standardized protocols to measure height and weight. Results: Results showed that obese status, not overweight status, was associated with future depressive symptoms, but not major depression. This study demonstrated that obesity is a risk factor for depressive symptoms, but not for clinical depression. Conclusions: As depressive symptoms are considered along the spectrum of depression with clinical depression at the high end, these results suggest that weight status could be considered a factor along the pathway of development of depression in some adolescent females. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
997.
Anna A. Stec Peter FardellPer Blomqvist Lucas Bustamante-ValenciaLaurent Saragoza Eric Guillaume 《Fire Safety Journal》2011,46(5):225-233
Gaseous fire effluents contain a mixture of components, some of which are present in toxicologically significant proportions, together with water vapour and particulate matter, representing a significant challenge to the analyst. The most useful information is obtained from fire gases at about 180 °C where water and most organic species are volatile. Despite this, it is often necessary to sample and measure fire effluents for prediction of fire toxicity, estimation of the environmental impact of fires, and to understand their behaviour.Gas phase Fourier Transform Infrared (FTIR) spectroscopy has the potential to measure almost all volatiles on a continuous basis during fire. This paper considers the key parameters, which must be carefully measured and controlled in order to obtain reliable calibration data. It evaluates a number of techniques designed for calibrating an FTIR spectrometer for use in fire gas analysis with conclusions on the best system for use for each species and for specific fire tests or experimental scenarios.As few molecules in the gas phase infrared spectrum obey the Beer-Lambert law, a full set of infrared spectra at different concentrations must be obtained for each target analyte, for the actual spectrophotometer—gas cell configuration in use. In some cases, stable standard mixtures are available, and these only have to be quantitatively diluted. In other cases reactive gases such as hydrogen halides must be generated quantitatively in situ, or vapours must be generated from volatile liquids under controlled conditions, in order to obtain calibration spectra. In each case, care must be taken in the design of the sampling line and calibration system, paying particular attention to the temperature, pressure and gas flow.Gas phase FTIR is a powerful analytical tool, but requires a significant investment in time and equipment before quantitative analysis can be undertaken. Unless care is taken to ensure constant temperature and pressure in the sample lines and gas cell, significant errors will result. 相似文献
998.
Frenette Eric; Gendron Martin; Hébert Marie-Hélène; Royer égide; Morand Céline 《Canadian Metallurgical Quarterly》2010,42(4):284
Behaviour difficulties (BD) in school-age children and adolescent constitute an increasingly important concern for all participants in the Quebec and foreign education systems. The risk factors that can contribute to the development of BD are numerous (Kauffman, 2005). Amongst these appears a whole set of skills related to social competence (Bowen, Desbiens, Martin, & Hamel, 2001). The present study aims to test, by means of Generalisability theory, the reliability of the evaluation process developed to measure the level of teenage social skills according to various indicators (cooperation, self-control, assertion), various sources of information (adolescent, parent, and teacher), and various times (pretest, posttest 1, posttest 2). The coefficient of relative generalisability was found to be higher than the limit considered satisfactory, indicating that the evaluation process is reliable enough to allow differentiation of social skills for adolescent with BD. To develop intervention guidelines for BD students, a review of the sources of variation that may influence the accuracy of the measurement provided by the evaluation process is conducted through an analysis of facets (Bertrand & Blais, 2004) and a study of the most important variances components (Bain & Pini, 1996). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
999.
1000.