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991.
Susane Moreira Machado Anderson Oliveira Lobo Ariel Bueno Loureiro Sapucahy Fernanda Roberta Marciano Evaldo Jose Corat Newton Soares da Silva 《Materials science & engineering. C, Materials for biological applications》2011,31(7):1614-1617
For the first time, we show that Tritrichomonas foetus can adhere on superhydrophilic vertically aligned carbon nanotubes (VACNT) films. Scanning electron microscopy shows an unusual adhesion with a higher membrane filopodium projection in all directions, directly attached to superhydrophilic VACNT tips. 相似文献
992.
Fabrícia M.S. Silva Luciano B. Oliveira Claudio F. Mahler João P. Bassin 《International Journal of Hydrogen Energy》2017,42(36):22720-22729
Hydrogen production from mesophilic anaerobic co-digestion of food waste (FW) and crude glycerol (GLC) was investigated in this study. Batch experiments were carried out at 35 °C for 36 h to assess the effect of supplementation of different glycerol concentrations (1%, 3% and 5% (v/v)) on dark fermentation of FW. The maximum hydrogen yield (180 mLH2/gVS) was obtained at 5% GLC while the maximum specific production rate (around 13 mLH2/(gVS.h)) was similar for all experiments with glycerol addition. Besides contributing to increase H2 productivity, the presence of glycerol reduced the microorganisms acclimation time (Lag phase) in comparison to the control tests conducted without this co-substrate. In addition, the increment of glycerol concentration also enhanced volatile fatty acids generation and favoured the production of 1,3-propanediol (1,3-PDO). In the experimental conditions studied (i.e., 1–5% (v/v) of GLC), the results revealed that co-digestion of FW and GLC is promising and can be potentially used to maximize energy production while contributing to the management and treatment of these wastes. 相似文献
993.
Nuno Lopes Paulo Vila Real Luís Simões da Silva Jean-Marc Franssen 《Fire Technology》2010,46(1):91-108
In this paper, the structural response of stainless steel thin-walled elements submitted to fire is analysed numerically by
means of the geometrically and materially non-linear Finite Element program SAFIR, including imperfections. In order to make
these simulations, two main changes in the program were made: (i) the code was changed in order to deal with the stainless
steel 2D material constitutive law to be used with shell elements and (ii) the possibility of the program to take into account
residual stresses with shell finite elements was introduced. The stainless steel stress–strain relationship at high temperatures
was based on the one presented in part 1.2 of Eurocode 3. To model the strain hardening exhibited by the stainless steels,
using the shell element formulation, an approximation to the Eurocode 3 constitutive law was needed. Local and global geometrical
imperfections were considered in the simulations. The paper shows the influence of the residual stresses on the ultimate load-carrying
capacity of thin-walled stainless steel structural elements in case of fire. 相似文献
994.
Sixty compounds of Lavandula angustifolia L. cultivated in Friuli Venezia Giulia (North-East Italy) were identified and quantified by GC-MS and GC-FID from essential oils obtained by means of hydrodistillation, and from extracts obtained by supercritical CO2 extraction (SFE) and ultrasound-assisted extraction (US). Using absolute calibration, a true quantification of 1-8 cineol, camphor, linalool, linalyl acetate and β-caryophyllene was carried out. The best extracts, in terms of amount of isolated compounds, flavour quality and stability were those obtained with SFE. Sonication performed at low amplitude for 5 min offered respect to high amplitude a promising alternative to hydrodistillation as a source of lavender flavouring ready to use for alcoholic beverages or/and confectionery products. 相似文献
995.
Eduardo Gomes Salgado Carlos Eduardo Sanches da Silva Carlos Henrique Pereira Mello Monique Samaan 《Engineering Management Journal; EMJ》2017,29(3):140-153
The development of new products has become increasingly critical for the competitiveness of companies, due to increased diversity and variety of products, the reduction of product life cycles, and, primarily, globalization of markets. Thus, the identification and prioritization of critical success factors for developing new products is important, particularly for the high degree of risk and uncertainty involved. The main objective of this article is the identification and prioritization of critical success factors in new product development projects in biotechnology companies in the state of Minas Gerais, Brazil. The research method used was a survey questionnaire, which was sent to a sample of 31 biotechnology companies in Minas Gerais state. The principal findings of this research are that interpersonal skills/relationships of the project leader and technical skills are the most critical factors for successful new product development in this industry. The implications for the biotechnology industry in general, as well as for those responsible for managing new product development, are discussed. 相似文献
996.
Geraldo Lúcio Tiago Filho Camila Rocha Galhardo Adriana de Cássia Barbosa Regina Mambeli Barros Fernando das Graças Braga da Silva 《Energy Policy》2011
This article presents the main regulatory changes that occurred in the Brazilian power sector in 2009, along with the impacts these changes caused on the market, especially related to small hydropower (<30 MW). This study addresses regulatory issues based on inventory studies and records of basic projects, changes related to the compensation of the assured energy of SHPs in the Brazilian energy reallocation market, the socio-economic impact resulting from the construction of SHPs, SHPs in alternative resource auctions and finally the general outlook for the growth scenario for SHPs in Brazil according to the ten-year plan (2010–2019). The overall conclusions of this investigation were that the 2008/2009 biennium was a period of great changes in the regulation of small hydropower plants in Brazil, and the SHP market has shown maturity. Additionally, despite SHP being a type of technology that is completely dominated by domestic industry, in recent years, they have experienced policy disincentives caused by changes to rules that inhibit their growth. 相似文献
997.
Ludovina R. Galego José P. Da Silva Valentim R. Almeida Maria R. Bronze Luís V. Boas 《International Journal of Food Science & Technology》2011,46(1):67-73
This work describes the preparation of aromatised liquors using deodorised and concentrated fruit distillates. The raw spirits were improved by making a partial deodorisation, using activated charcoal, followed by concentration, using a distiller. The liquors were prepared by a maceration process. The procedure is exemplified using fig distillates to prepare myrtle berry liquors. The acidity, copper, polyphenol and anthocyanin indexes and volatile and anthocyanin profiles were monitored in each preparation step. The concentration process increased the ethanol proof to 75% v/v and decreased the acidity and the copper content. The partial deodorisation decreased the levels of high molecular weight volatiles, while the content of lower molecular weight compounds that contribute to flavour was maintained. Delphinidin‐3‐O‐glucoside, cyanidin‐3‐O‐glucoside, petunidin‐3‐O‐glucoside and malvidin‐3‐O‐glucoside were the major anthocyanins. 相似文献
998.
Ruthiano Simioni Munaretti Taisy Silva Weber Sérgio Luis Cechin Bruno Coswig Fiss 《Journal of Electronic Testing》2011,27(4):531-539
In an operational environment, the identification and reproduction of faults may be hard to be done, specially in complex
systems. Use of fault injection accelerates this process, improving the test of fault tolerance mechanisms. However, there
are a significant amount of fault injectors available, using several different approaches. This diversity of tools, each one
with different methods to describe faultloads for fault injection campaigns, imposes severe obstacles to the efficient use
of such fault injectors. In this context, this paper presents jFaultload, which applies Java for the specification of faultloads and translates them to specific formats that are appropriate to each
available fault injector. Fault injectors for communication systems were integrated in the environment and completes the test
scenario. The service under test used to demonstrate the usability and expressiveness of our solution is a video streaming
session using RTP Protocol. 相似文献
999.
R.C. Carbonari P.A. Muñoz-Rojas E.Q. Andrade G.H. Paulino K. Nishimoto E.C.N. Silva 《International Journal of Pressure Vessels and Piping》2011,88(5-7):198-212
Previous papers related to the optimization of pressure vessels have considered the optimization of the nozzle independently from the dished end. This approach generates problems such as thickness variation from nozzle to dished end (coupling cylindrical region) and, as a consequence, it reduces the optimality of the final result which may also be influenced by the boundary conditions. Thus, this work discusses shape optimization of axisymmetric pressure vessels considering an integrated approach in which the entire pressure vessel model is used in conjunction with a multi-objective function that aims to minimize the von-Mises mechanical stress from nozzle to head. Representative examples are examined and solutions obtained for the entire vessel considering temperature and pressure loading. It is noteworthy that different shapes from the usual ones are obtained. Even though such different shapes may not be profitable considering present manufacturing processes, they may be competitive for future manufacturing technologies, and contribute to a better understanding of the actual influence of shape in the behavior of pressure vessels. 相似文献
1000.
Sturtevant B. Davulis P. Da Cunha M. 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2009,56(4):788-797
This work reports on the determination of langatate elastic and piezoelectric constants and their associated temperature coefficients employing 2 independent methods, the pulse echo overlap (PEO) and a combined resonance technique (CRT) to measure bulk acoustic wave (BAW) phase velocities. Details on the measurement techniques are provided and discussed, including the analysis of the couplant material in the PEO technique used to couple signal to the sample, which showed to be an order of magnitude more relevant than the experimental errors involved in the data extraction. At room temperature, elastic and piezoelectric constants were extracted by the PEO and the CRT methods and showed results consistent to within a few percent for the elastic constants. Both raw acquired data and optimized constants, based on minimization routines applied to all the modes involved in the measurements, are provided and discussed. Comparison between the elastic constants and their temperature behavior with the literature reveals the recent efforts toward the consistent growth and characterization of LGT, in spite of significant variations (between 1 and 30%) among the constants extracted by different groups at room temperature. The density, dielectric permittivity constants, and respective temperature coefficients used in this work have also been independently determined based on samples from the same crystal boule. The temperature behavior of the BAW modes was extracted using the CRT technique, which has the advantage of not relying on temperature dependent acoustic couplants. Finally, the extracted temperature coefficients for the elastic and piezoelectric constants between room temperature and 120degC are reported and discussed in this work. 相似文献