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151.
Andrea Ciancone Mauro Luigi Drago Antonio Filieri Vincenzo Grassi Heiko Koziolek Raffaela Mirandola 《Software and Systems Modeling》2014,13(4):1269-1290
Automatic prediction tools play a key role in enabling the application of non-functional requirements analysis, to simplify the selection and the assembly of components for component-based software systems, and in reducing the need for strong mathematical skills for software designers. By exploiting the paradigm of Model-Driven Engineering (MDE), it is possible to automatically transform design models into analytical models, thus enabling formal property verification. MDE is the core paradigm of the KlaperSuite framework presented in this paper, which exploits the KLAPER pivot language to fill the gap between design and analysis of component-based systems for reliability properties. KlaperSuite is a family of tools empowering designers with the ability to capture and analyze quality of service views of their systems, by building a one-click bridge towards a number of established verification instruments. In this article, we concentrate on the reliability-prediction capabilities of KlaperSuite and we evaluate them with respect to several case studies from literature and industry. 相似文献
152.
Kuo-Chung Liu † Gareth Thomas Angel Caballero Jose S. Moya Salvador de Aza 《Journal of the American Ceramic Society》1994,77(6):1545-1552
The C-shaped time-temperature-transformation curves (T-T-T curves) of cristobalite formation and the L-shaped T-T-T curves of α-alumina reaction were established for a high-purity kaolinite-α-alumina mixture during heating. The results revealed that cristobalite formation in kaolinite was retarded by the presence of α-alumina between 1250° and 1350°C and was totally prohibited above 1380°C due to the reaction of kaolinite with α-alumina to form secondary mullite. The reaction of α-alumina with kaolinite was initiated at about 1250°C. It became quite extensive above 1380°C and was extremely fast at 1600°C and above, indicating the strong effect of the eutectic liquid formation at ∼1587°C in silica-alumina. The effectiveness of the established T-T-T curves was demonstrated and discussed. 相似文献
153.
Antonio G. González Ignacio A. Jiménez Mercedes P. Núñez Angel G. Ravelo Isabel L. Bazzocchi Orlando M. Muñoz Marcelino A. Aguilar 《Journal of chemical ecology》1994,20(4):823-830
Three new dihydro--agarofuran sesquiterpenes from two species ofMaytenus were isolated and their structures were elucidated by means of1H and13C NMR studies. The differences and similarities noted in the chemical content of the dihydro--agarofuran sesquiterpenes from the fourMaytenus species from Chile are in line with the taxonomic characterization of these species; their geographical distribution is also given. 相似文献
154.
Antonio Romero-Serrano Carlos Gomez-Yañez Manuel Hallen-Lopez Jorge Araujo-Osorio 《Journal of the American Ceramic Society》2005,88(1):141-145
The evaluation of the thermodynamic properties as well as the phase diagrams for the binary Na2 O–SiO2 , K2 O–SiO2 , and Li2 O–SiO2 systems are carried out with a structural model for silicate melts and glasses. This thermodynamic model is based on the assumption that each metallic oxide produces the depolymerization reaction of silica network with a characteristic free-energy change. A least squares optimization program permits all available thermodynamic and phase diagram data to be optimized simultaneously. In this manner, data for these binary systems have been analyzed and represented with a small number of parameters. The resulting equations represent the thermodynamic and phase diagram data for these alkali metal oxide–silica systems within experimental error limits. In particular, the measured limiting liquidus slope at is well reproduced. 相似文献
155.
Mirela Rada Ángeles Guinda Jose Cayuela 《European Journal of Lipid Science and Technology》2007,109(11):1071-1076
Molecular distillation, or short‐path distillation (SPD), is particularly appropriate for processing of low‐volatility compounds, which are easily altered at high temperature. Olea europaea L. leaves constitute an olive tree by‐product very interesting for their natural antioxidants content. In this research, molecular distillation technology has been applied to obtain high‐value‐added compounds by the SPD fractionation of an olive tree leaf extract. The process consists of two stages: (a) ethanolic extraction of the olive leaves, followed by incorporation of the extract into glycerine and (b) molecular distillation of the glycerine enriched in olive leaf extract compounds (terpenic and phenolic compounds). Four molecular distillation tests under different conditions were carried out. Results showed that 80.9% 3,4‐dihydroxy‐phenylethanol (hydroxytyrosol) was recovered from the glycerine admixture under a pressure of 1.50–2.00 mbar, a temperature of 190 °C and a feed rate of 15 mL/min. 相似文献
156.
Jose E. Herrera Ja Hun Kwak Jian Zhi Hu Yong Wang Charles H. F. Peden 《Topics in Catalysis》2006,39(3-4):245-255
The advantages of the atomic layer deposition (ALD) method for preparation of tungsten, vanadium, titanium, and molybdenum
oxide catalyst supported on mesoporous silica are discussed, with emphasis on the importance of synthesis conditions on dispersion,
structure and activity of the resulting materials. A suite of complementary techniques such as DRS-UV/Vis, BET, 1H-NMR, XRD, and TEM were used to study the structural properties of the supported metal oxides, and probe reactions such as
2-butanol dehydration and ethanol partial oxidation were used to demonstrate the potential advantages of the ALD-prepared
catalysts. Specifically, highly dispersed oxides of titanium, molybdenum, and tungsten oxide on mesoporous silica were synthesized
using the ALD method. It is also demonstrated that attainment of high dispersions of vanadium oxide on mesoporous silica requires
the presence of at least a single layer of titanium oxide due to the well-known poor interaction between vanadia and silica.
The highly dispersed catalysts prepared here by ALD methods exhibited superior catalytic performance relative to those prepared
using conventional incipient wetness impregnation. 相似文献
157.
de Almeida Jhony Luiz Comunello Eros Sobieranski Antonio da Rocha Fernandes Anita Maria Cardoso Gabriel Schade 《Pattern Analysis & Applications》2021,24(3):907-914
Pattern Analysis and Applications - Digital holography is an imaging process able to recreate three-dimensional representations of objects from recording pattern interference among distinct waves.... 相似文献
158.
Gabriele Pisano Antonio Bonati Gianni Royer Carfagni 《Journal of the American Ceramic Society》2021,104(1):383-403
The probability of breakage in service lifetime of heat-tempered glass panes contaminated by nickel sulfide inclusions is estimated with a multiscale micromechanically motivated statistical theory, which considers the effects of the heat soak test (HST). Short and long HSTs differently affect the phase transformation of NiS of diverse chemical composition, whose increase in volume can break the glass. The main hypothesis, corroborated by experiments, is that there is a lower limit for the size of NiS stones below which no crack can be initiated from the volumetric expansion. The catastrophic propagation of nucleated fractures in the long term is modeled through a rescaled critical stress intensity factor, which accounts for the subcritical crack propagation and the slow phase transformation of NiS. A parametric analysis evidences how the failure probability is strongly affected by these parameters, depending on the holding time in the HST. Tailored experimental activity is suggested for the proper calibration of the model. 相似文献
159.
Kaio C. S. Rodrigues Ivan I. K. Veloso Marcelo P. A. Ribeiro Antonio J. G. Cruz Alberto C. Badino 《加拿大化工杂志》2021,99(1):401-409
Fast, simple, accurate, and inexpensive methods for obtaining analyte concentration data are desirable in the industrial sector. In the present study, the use of Fourier transform mid‐infrared (FT‐MIR) spectroscopy, combined with partial least squares (PLS) regression, was investigated as a tool for real‐time monitoring of processes of ethanol absorption in glycols. Calibration was performed using simple synthetic samples containing ethanol, water, and monoethylene glycol (MEG) or diethylene glycol (DEG). The PLS models presented excellent performance, with correlation coefficients (R2) close to unity and root‐mean‐square errors of cross‐validation (RMSECV) and prediction (RMSEP) lower than 2% of the calibration data ranges for both analytes (ethanol and water) in both absorbents (MEG and DEG). The monitoring technique developed has potential to be applied in absorption processes and could also be used in other large‐scale unit operations, providing information in real time and enhancing process control. 相似文献
160.
Milton Jimenez-Francisco Jose Gonzalo Carrillo Luis Alfonso Garcia-Cerda 《应用聚合物科学杂志》2021,138(1):49628
Mechanochemical degradation by planetary ball milling (PM) is used for postpolymerization modification of styrene homopolymers (PS). A complete factorial design was chosen to study the effect of radical scavengers, milling time, initial molecular weight, and revolution radius (Rp), on the shape of molecular weight distributions (MWDs) of PS. Size-exclusion chromatography analysis shows the feasibility of fine-tuning MWD of PS at up to 40% conversion. Distributions ranged from unimodal to bimodal in a PM with Rp = 150 mm at different stage of milling, whereas in a PM with Rp of 60.8 mm the adjustment of unimodal distributions is achieved. Initial polydispersity is more important to develop bimodal distributions when compared with initial molecular weight. Fourier transform infrared and X-ray electron spectrometry analysis show some suppression of PS degradation and complete oxidation inhibition of macromolecular radicals with the incorporation of radical scavengers, which we considered as additional aids when adjusting the MWDs. 相似文献