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61.
We report the detailed temperature dependence of the electrical resistivity of EuMo6S8 as a function of pressure up to 70 kbar under quasihydrostatic pressure conditions. The effect of an external magnetic field on the electrical resistivity has been studied at selected temperatures and pressures. Our results, which are qualitatively different from those reported under hydrostatic pressure conditions, can be explained on the basis of a proposed coexistence of the untransformed rhombohedral phase and the transformed triclinic phase of EuMo6S8.  相似文献   
62.
Kraft black liquor/green liquor was continuously recirculated in a column (diameter 100 mm, height 450 mm) packed with 16-mm polypropylene Pall rings countercurrent to a gas stream containing N2 and O2 (O2–3.7%). The concentration of sulphide in the green liquor was not affected by oxygen in the gas; the latter, however, completely oxidised the sulphide in kraft black liquor over an 8 h recirculation period.  相似文献   
63.
In designing an implantable sensor for perfusion monitoring of transplant organs the ability of the sensor to gather perfusion information with limited power consumption and in near real time is paramount. The following work was performed to provide a processing method that is able to predict perfusion and oxygenation change within the blood flowing through a transplanted organ. For this application, an autocorrelation-based algorithm was used to reduce the acquisition time required for fast Fourier transform (FFT) analysis while retaining the accuracy inherent to FFT analysis. In order to provide data proving that the developed method is able to predict perfusion as accurately as FFT two experiments were developed isolating both periodic and quasi-periodic cardiac frequencies. It was shown that the autocorrelation-based method was able to perform comparably with FFT (limited to a sampling frequency of 300 Hz) and maintain accuracy down to acquisition times as low as 4 s in length.  相似文献   
64.
We investigate ambient services, which we define as services that are related to the surrounding physical environment of the user, are locally useful and can be considered a form of location-based services. We introduce the notion of service domain which refers to the geographical area of relevance and utility for ambient services. We also consider a stereotypical case where a user might be within multiple service domains at the same time (when the service domains containing the user overlap) and so, can utilize a collection of services comprising services selected from each of the service domains containing the user. A language of operators is given for defining such a collection of services in terms of constituent services from the overlapping service-domains. Moreover, we describe and evaluate a prototype system that shows how to compute the services for a user in multiple service domains. The result is a framework for reasoning about ambient services for filtering or proactively suggesting mobile services based on geographical boundaries. Seng Wai Loke is a Faculty of Information Technology Research Fellow at Monash University. He is author and co-author of more than 90 research papers published in journals, books, conferences, and workshops. His research interests are intelligent and mobile agents, service-oriented computing, and pervasive computing including device ecologies, context-aware systems, mobile services, and ubiquitous e-commerce. He has been on the program committee of more than ten conferences and workshops in the area of mobile computing and agents. Shonali Krishnaswamy received a PhD in Computer Science from Monash University (Australia) in 2003. She currently holds the position of a Research Fellow in the School of Computer Science and Software Engineering at Monash University. Her research interests include Service Oriented Systems, Software Agents and Distributed/Ubiquitous Data Mining. She is a member of ACM and IEEE Computer Societies. Thin Thin Naing has completed her Masters by Information Technology (MIT by Minor Thesis) from the School of Computer Science and Software Engineering at Monash University, Australia. Her research interests include Mobile Services, Location-based Services and Ambient services.This revised version was published online in August 2005 with a corrected cover date.  相似文献   
65.
A method using Hermite polynomials is utilized for analyzing the outputs of νth-law devices for inputs of modulated Gaussian signals and zero-mean Gaussian noise. New results are developed for the output correlation functions, and techniques for obtaining closed-form expressions are pointed out. Output signal-to-noise ratios for various input carrier-to-noise-power ratios are calculated, and plots are shown for a single sinusoidal modulating signal. Results are derived to show the existence of a theoretical maximum for the output signal-to-noise ratio. The method can be directly applied for the case of general Fourier expandable signals modulating a Gaussian carrier.  相似文献   
66.
Applied a random effects linear model to personality data (e.g., the Eysenck Personality Questionnaire and the Comrey Personality Scales) gathered from 138 adult Swedish twins and their families. The multiple relationships surrounding the twins allowed for the estimation of variance fractions due to several genetic and environmental factors. A striking pattern of similarity among personality traits emerged. All variables were characterized by having near-zero additive genetic, small–moderate nonadditive genetic, negligible prenatal, small postnatal familial, and quite large postnatal extrafamilial effects. Personality traits were influenced primarily by the environment, especially those outside the home. Genetic influences were confounded by cultural factors. It is suggested that temporal instability, genetic epistasis, or both could be underlying factors that unify the results for personality variables. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
67.
68.
The present work studies an aerogel/epoxy composite that was dip coated onto a carbon fibre substrate by adding the aerogel at the 1?h and the 1.5 mark of the epoxy cure. Both coatings show decrease in thermal conductivity values (39% and 47% respectively) when compared to a pure epoxy coating. The coatings’ reflectance spectra also provided further evidence for the existence of the nano-pores within the aerogel particles. The aerogel coating was modelled using material properties from literature and solved using finite element methods. The model, which validated using experimental data, was then used to predict the coating’s performance in cyclic thermal loads. Additionally, coatings on a single surface- top and bottom; were also modelled and compared with the double coating system wherein it was seen that the double coating system had the lowest rate of temperature change and fluctuations at steady-state in contrast to the bottom coating which, showed the fastest drop in temperature as well as the highest fluctuations at steady state conditions. The performance of the top coating was in the middle.  相似文献   
69.
70.
Phytomediated synthesis of metal oxide nanoparticles has become a key research area in nanotechnology due to its wide applicability in various biomedical fields. The present work explores the biosynthesis of zinc oxide nanoparticles(ZnO-NPs) using Leucaena leucocephala leaf extract. The synthesised ZnO-NPs were characterised by ultraviolet-visible(UV-Vis) spectroscopy, scanning electron microscopy(SEM), energydispersive X-ray spectroscopy(EDX), Fourier transform infrared spectroscopy(FTIR), X-ray diffraction(XRD),transmission electron microscopy(TEM) and selected area electron diffraction(SAED) studies. Biosynthesised ZnONPs are found to have wurtzite hexagonal structure with particles distributed in the range of 50-200 nm as confirmed by TEM studies. The anticancer activity of ZnONPs against MCF-7(breast cancer) and PC-3(human prostate cancer) cell lines was evaluated using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide(MTT) assay. From the assay, biosynthesised ZnO-NPs have better cytotoxic activity on PC-3 cell lines than MCF-7 cell lines. The in vitro cytotoxicity studies of biosynthesised ZnO-NPs against Dalton lymphoma ascites(DLA)cells reveal better antitumor activity of 92% inhibition with concentration of 200 μg·ml~(-1) of ZnO-NPs,and as the concentration increases, the anticancer efficiency as well increases, and also, it has excellent photocatalytic activity to degrade crystal violet dye in aqueous solution after irradiation of 90 min. The result suggests that the green synthesis of ZnO-NPs could be easily recovered and reused several times without any significant loss of the catalytic activity. The advantage of this technique lies in its low cost, easily climb able and non-use of toxic agents.  相似文献   
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