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991.
992.
Cleonardo Augusto Silva Arthur Ribeiro-dos-Santos Wanderson Gonalves Gonalves Pablo Pinto Rafael Pompeu Pantoja Tatiana Vinasco-Sandoval Andr Maurício Ribeiro-dos-Santos Mara Helena Hutz Amanda Ferreira Vidal Gilderlanio Santana Araújo ndrea Ribeiro-dos-Santos Sidney Santos 《International journal of molecular sciences》2021,22(7)
Simple SummaryTuberculosis is the leading cause of mortality from a single infectious agent and is among the top 10 causes of death worldwide. Despite that, few studies focus on regulatory elements such as small non-coding RNAs in tuberculosis. This pilot work applied Next Generation Sequencing techniques to evaluate the global miRNA expression profile of patients with active tuberculosis; their respective healthy physicians, who are at constant risk of infection; and a second group of healthy controls. In addition, we observed miRNA–gene interactions affected by exposure to the bacteria. Our findings indicate a list of miRNAs that could be used as potential biomarkers to improve treatment strategies at early stages. We also observed modified pathways related to the immune response due to differential miRNA expression profiles. Finally, we alert and encourage the development of new strategies to avoid long-term exposure of healthy physicians, considering how closely related their miRNA profile was to tuberculosis patients using current safety protocols.AbstractThe role of regulatory elements such as small ncRNAs and their mechanisms are poorly understood in infectious diseases. Tuberculosis is one of the oldest infectious diseases of humans and it is still a challenge to prevent and treat. Control of the infection, as well as its diagnosis, are still complex and current treatments used are linked to several side effects. This study aimed to identify possible biomarkers for tuberculosis by applying NGS techniques to obtain global miRNA expression profiles from 22 blood samples of infected patients with tuberculosis (n = 9), their respective healthy physicians (n = 6) and external healthy individuals as controls (n = 7). Samples were run through a pipeline consisting of differential expression, target genes, gene set enrichment and miRNA–gene network analyses. We observed 153 altered miRNAs, among which only three DEmiRNAs (hsa-let-7g-5p, hsa-miR-486-3p and hsa-miR-4732-5p) were found between the investigated patients and their respective physicians. These DEmiRNAs are suggested to play an important role in granuloma regulation and their immune physiopathology. Our results indicate that miRNAs may be involved in immune modulation by regulating gene expression in cells of the immune system. Our findings encourage the application of miRNAs as potential biomarkers for tuberculosis. 相似文献
993.
João Victor Barbosa Moura Antonio Amison Gomes de Souza Paulo de Tarso Cavalcante Freire Cleanio da Luz Lima Thiago Mielle Brito Ferreira Oliveira 《International Journal of Applied Ceramic Technology》2021,18(3):615-621
We report the structural, morphological, and optical characterization, and the application of sodium-cerium molybdate (NaCe(MoO4)2) as a promising photoelectroactive material for water splitting. Information on these several properties was obtained by X-ray diffraction, Raman spectroscopy, scanning electron microscopy, and UV–Vis–NIR diffuse reflectance. For the photoelectrochemical tests, NaCe(MoO4)2 microcrystals were deposited on conductive indium-tin oxide (ITO) glass substrate by drop coating, and the activity of the as-prepared photoanode toward oxygen evolution reaction was investigated in the absence and presence of blue light-emitting diode irradiation. Studies carried out by linear sweep voltammetry, chronoamperometry, and electrochemical impedance spectroscopy attested to a significant photoelectroactivity of molybdate associated with the fast electron-hole pairs generation. The steady-state photocurrent density recorded under irradiation achieved a remarkable increase, varying from 1.5 µA cm−2 (light off) to 44.1 µA cm−2 (light on), in addition, it presents high stability after on–off cycles, what proves the proper performance of NaCe(MoO4)2/ITO as photoanode for water splitting. 相似文献
994.
The paper aims at analysing the performance of Polyester Polymer Concrete (PPC) reinforced with steel and FRP rebars. The PPC is also compared with conventional cement concrete.
On the one hand, the effect of the polymer matrix microstructure on the mechanical performance (compression and flexural strength, deformability and Young’s modulus) is discussed.
On the other hand, static and dynamic bond behaviour under pure pull-out forces between the PPC and different rebars is tackled. It is analysed the behaviour of metallic and non-metallic rebars embedded in a PPC matrix when they are subjected to both monotonic and cyclic loads. Likewise, analogous tests were performed on cement concrete specimens in order to be able to compare the bonding performance in both types of concrete. 相似文献
995.
Given a set S of radio stations located on a line and an integer h ≥ 1 , the MIN ASSIGNMENT problem consists in finding a range assignment of minimum power consumption provided that any pair of stations can communicate in at most h hops. Previous positive results for this problem are only known when h=|S|-1 or in the uniform chain case (i.e., when the stations are equally spaced). As for the first case, Kirousis et al. [7] provided a polynomial-time algorithm while, for the second case, they derive a polynomial-time approximation algorithm. This paper presents the first polynomial-time, approximation algorithm for the MIN ASSIGNMENT problem. The algorithm guarantees a 2-approximation ratio and runs in O(hn 3 ) time. We also prove that, for fixed h and for ``well spaced'' instances (a broad generalization of the uniform chain case), the problem admits a polynomial-time approximation scheme . This result significantly improves over the approximability result given by Kirousis {et al}. Both our approximation results are obtained via new algorithms that exactly solve two natural variants of the MIN ASSIGNMENT problem: the problem in which every station must reach a fixed one in at most h hops and the problem in which the goal is to select a subset of bases such that all the other stations must reach one base in at most h-1 hops. Finally, we show that for h=2 the MIN ASSIGNMENT problem can be exactly solved in O(n 3 ) time. 相似文献
996.
Wavelet shrinkage estimation has become an attractive and efficient method for signal denoising and compression. Despite the ample variety of methods which have been used in the wavelet denoising context, it has proven elusive to construct threshold estimators with good adaptive properties. Recently, empirical Bayes selection criteria have been proposed to derive adaptive shrinkage estimators. We consider the application of empirical Bayes variable selection criteria to each level of the wavelet transform to obtain adaptive threshold estimates. A set of level-dependent hyperparameters has to be estimated to derive nonlinear data-dependent thresholding rules. We propose the use of an evolutionary algorithm to calibrate the multilevel parameters, in order to automate parameter selection and enhance adaptivity of the threshold estimators. Comparative simulations on a set of standard model functions show good performance. Applications to data drawn from various fields of application are used to explore the practical performance of the proposed approach. 相似文献
997.
van Dijk E. Ferreira J.A. van Gelder P. 《Industry Applications, IEEE Transactions on》2002,38(6):1600-1605
The layout of a capacitor bank with clamping diodes is investigated based on an experimental 5.5-kJ energy storage unit for pulsed power applications. While the current sharing between parallel-connected capacitors is good, it is not the case with parallel-connected clamping diodes. Despite a very-low-inductance busbar and attention to symmetrical layout, unequal current sharing results. Good agreement was obtained between measured waveforms and a detailed simulation model. The simulation model indicated that the unequal current sharing is due to small differences between the coupling factors of the parasitic busbar inductances near the capacitors at the ends and at the middle of the bank. It is concluded that the best solution is to place the parallel diodes as close as possible to each other at a position where best averaged coupling is achieved with the individual capacitors of the bank. 相似文献
998.
Z. J. Pei P. M. Ferreira S. G. Kapoor M. Haselkorn 《International Journal of Machine Tools and Manufacture》1995,35(7)
Among the various material removal processes applicable to ceramic materials, rotary ultrasonic machining has the potential for high material removal rate while maintaining low machining pressure and resulting in less surface damage. The limitation of rotary ultrasonic machining is that only circular holes or cavities can be machined due to the rotary motion of the tool. Attempts have been made by other researchers to extend rotary ultrasonic machining process to machining flat surfaces or milling slots. However, these extensions either changed the material removal mechanisms or had some severe drawbacks. One of the reasons for this might be an insufficient understanding of the material removal mechanisms involved. In this paper, a new approach to extend rotary ultrasonic machining to face milling of ceramics is proposed, which keeps all the material removal mechanisms of rotary ultrasonic machining. The development of the experimental apparatus and the design of the cutting tool are described. Preliminary experimental results are presented and discussed. 相似文献
999.
The present work aims at evaluating the anti-corrosion behaviour of a novel pre-treatment based on bis-[triethoxysilylpropyl] tetrasulfide (BTESPT) doped with cerium nitrate for application on hot dip galvanised steel and AA2024-T3 substrates. The corrosion resistance was evaluated by electrochemical impedance spectroscopy (EIS) and by the scanning vibrating electrode technique (SVET), during immersion in NaCl solutions. The electrochemical results showed that the pre-treatment provides excellent corrosion protection to the substrates. Furthermore, the results evidenced improved protection comparatively to the use of undoped BTESPT pre-treatments, both for galvanised steel and AA2024-T3. This improvement is most likely due to enhanced barrier properties of the film and additional active corrosion protection originated from the inhibiting action of the cerium-based inhibitor impregnated in the silane matrix. 相似文献
1000.
Sara Monteiro Maria A Piarra‐Pereira Maria Conceio Tanganho Jos Pedro Rente Virgílio B Loureiro Artur R Teixeira Ricardo B Ferreira 《Journal of the science of food and agriculture》1999,79(5):772-778
Immunology is an expanding area of research with potentially important applications in the analysis of many biological molecules. Polyclonal antibodies were raised in rabbits against specific proteins as well as against the total protein from a Portuguese wine. FPLC cation exchange chromatography was used to isolate the total protein fraction and, when in combination with denaturing electrophoresis, to purify individual wine polypeptides. To obtain a high titre, an injection of each antigen followed by three boosters were given in the immunisation of each rabbit. The titre of the antisera was measured by the ELISA technique and the specificity of the antibodies detected by immunoblotting. The antibodies produced were shown to be highly specific for the corresponding antigens. However, antibodies obtained specifically against a highly purified wine polypeptide seem to recognize the other major wine polypeptides, raising the possibility of structure similarity between different wine proteins. Neither the anti‐total wine protein antibodies not the anti‐specific wine protein antibodies originated a signal when used to probe thaumatin or chitinase. © 1999 Society of Chemical Industry 相似文献