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61.
Identifying file systems metadata changes such as which files have been added, modified or removed from the file system has many usages. In this paper we present a framework we developed for identifying those changes in increasing speeds. Our framework which is composed of crawling, hashing, and scheduling components, allows to scale the crawl to multiple client workstations that operate in parallel on the same file system in a non-overlapping fashion. Experiments carried using real-world data indicate performance improvement (speedup) of up to 36X using our framework compared to legacy crawling utilities such as Linux’s ‘find’. 相似文献
62.
Predicting phase behavior in aqueous systems without fitting binary parameters II: Gases and non‐aromatic hydrocarbons 下载免费PDF全文
Ilya Polishuk Helena Lubarsky Dong NguyenHuynh 《American Institute of Chemical Engineers》2017,63(11):5064-5075
This investigation continues a series of studies evaluating the capability of the recently proposed CP‐PC‐SAFT and sPC‐SAFT of Liang et al. to estimate the thermodynamic properties of aqueous systems in the entirely predictive manner. Similarly to the previously considered systems, CP‐PC‐SAFT remains a realistic estimator of the available data on critical loci, high pressure‐high temperature phase equilibria and volumetric properties also in the cases of non‐polar gases and non‐aromatic hydrocarbons from argon and nitrogen till n‐eicosane and squalene while keeping zero values of binary parameters. Nevertheless, such application of the model poses certain unavoidable compromises on its accuracy. Inter alia, CP‐PC‐SAFT is a particularly inaccurate estimator of the water‐rich liquid phases away from the critical points. sPC‐SAFT predicts these data in a more reliable manner. Moreover, its predictive capability goes beyond the liquid phases and it exhibits a remarkable accuracy in forecasting various phase equilibria below the critical point of water. © 2017 American Institute of Chemical Engineers AIChE J, 2017 相似文献
63.
Kinetics of phase formation in the Ln–O–S (Ln=La,Gd, Y) systems during oxide sulfidation in ammonium thiocyanate vapor 下载免费PDF全文
Vladimir V. Bakovets Aleksandr V. Sotnikov Ilya V. Korolkov 《Journal of the American Ceramic Society》2017,100(4):1320-1329
Kinetics and mechanism of phase formation in the Ln–O–S (Ln=La, Gd, Y) systems during Ln2O3 sulfidation in ammonium thiocyanate vapor and the identified sequence of transformations of obtained phases in the temperature range 873‐1273 K have been studied. The kinetic dependencies for the reactions involved were fitted by the Jander equation for topochemical heterogeneous reactions with a squared correlation coefficient R2=.99. The reaction rate constants, pre‐exponential factors, and effective activation energies for the reaction formation of compounds have been calculated, and approximate times and low temperatures for the formation of particular phases have been found. 相似文献
64.
Ilya Chukhman Yang Jiao Haifa Ben Salem Shuvra S. Bhattacharyya 《Journal of Signal Processing Systems》2016,84(3):383-397
Dataflow modeling offers a myriad of tools for designing and optimizing signal processing systems. A designer is able to take advantage of dataflow properties to effectively tune the system in connection with functionality and different performance metrics. However, a disparity in the specification of dataflow properties and the final implementation can lead to incorrect behavior that is difficult to detect. This motivates the problem of ensuring consistency between dataflow properties that are declared or otherwise assumed as part of dataflow-based application models, and the dataflow behavior that is exhibited by implementations that are derived from the models. In this paper, we address this problem by introducing a novel dataflow validation framework (DVF) that is able to identify disparities between an application’s formal dataflow representation and its implementation. DVF works by instrumenting the implementation of an application and monitoring the instrumentation data as the application executes. This monitoring process is streamlined so that DVF achieves validation without major overhead. We demonstrate the utility of our DVF through design and implementation case studies involving an automatic speech recognition application, a JPEG encoder, and an acoustic tracking application. 相似文献
65.
Triacetone triperoxide (C(9)H(18)O(6), molecular mass of 222.24 g/mol) (TATP) is a powerful explosive that is easy to synthesize using commonly available household chemicals, acetone, and hydrogen peroxide 1 2. Because of the simplicity of its synthesis, TATP is often the explosive of choice for terrorists, including suicide bombers. For providing safety to the population, early detection of TATP and isolation of such individuals are essential. We report unambiguous, high-sensitivity detection of TATP and its precursor, acetone, using room-temperature quantum cascade laser photoacoustic spectroscopy (QCL-PAS). The available sensitivity is such that TATP, carried on a person (at a nominal body temperature of 37 degrees C), should be detectable at some distance. The combination of demonstrated detection of TATP and acetone should be ideal for screening at airports and other public places for providing increased public safety. 相似文献
66.
Grigory Kovtun Tatiana Kameneva Serhy Hladyi Mykhailo Starchevsky Yury Pazdersky Igor Stolarov Michael Vargaftik Ilya Moiseev 《Advanced Synthesis \u0026amp; Catalysis》2002,344(9):957-964
Redox disproportionation of benzyl alcohol to benzaldehyde and toluene catalysed by the Pd561phen60(OAc)180 (phen=1,10‐phenanthroline) giant cluster 1 under anaerobic conditions was found, whereas in an O2 atmosphere cluster 1 catalyses the oxidation of benzyl alcohol to benzaldehyde and inhibits further oxidation of the latter. A study of the AIBN‐initiated and non‐initiated oxidation of benzyl alcohol, sec‐butyl alcohol and styrene in the presence of cluster 1 revealed that cluster 1 performs three functions in the oxidation reactions: 1) catalysis of polar oxidation of the substrates with O2, 2) termination of the chains of radical oxidation, and 3) catalysis of redox disproportionation. 相似文献
67.
Pettit Jeremy W.; Roberts Robert E.; Lewinsohn Peter M.; Seeley John R.; Yaroslavsky Ilya 《Canadian Metallurgical Quarterly》2011,25(1):127
Longitudinal trajectories of depressive symptoms, perceived support from family, and perceived support from friends were examined among 816 emerging adults (480 women; 59%). In the context of a larger longitudinal investigation on the predictors and course of depression, data were drawn from eight self-report questionnaire assessments that roughly spanned the third decade of life. An age-based scaling approach was used to model trajectories of depressive symptoms and perceived social support between the ages of 21 and 30. Associative models of the relations between depressive symptoms and perceived social support from family and friends were tested. Results indicated that depressive symptoms decreased and perceived social support increased during the study period. Associative models suggested that among women, higher initial levels of perceived support from family predicted slower decreases in depressive symptoms (b = .34, p 相似文献
68.
Ilya B. Simanovskii Antonio Viviani Frank Dubois Jean-Claude Legros 《Microgravity science and technology》2013,25(3):141-151
The influence of the horizontal component of the temperature gradient on nonlinear oscillatory convective flows, developed under the joint action of buoyant and thermocapillary effects in the 47 v2 silicone oil - water system, is investigated. The layers of equal thicknesses are considered. Transitions between nonlinear regimes of convection, have been studied. It is shown that under the action of the horizontal component of the temperature gradient, the asymmetric oscillatory flow takes place in the system. 相似文献
69.
Water distribution systems are spatially diverse. As such, they are inherently vulnerable to accidental or deliberate physical, chemical, or biological threats. Efficient water quality monitoring is one of the most important tools to guarantee a reliable potable water supply. A methodology and two example applications for finding the optimal layout of a detection system, taking explicitly into account the dilution and decay properties of the water quality constituents as distributed with flow, as well as the ability of the monitoring equipment to detect contaminant concentrations, are formulated and demonstrated. The detection system outcome is aimed at capturing contaminant entries within a pre-specified level of service (LOS) defined as the maximum volume of polluted water exposure to the public at a concentration higher than a minimum hazard level. The proposed methodology couples hydraulic simulations with graph theory techniques to identify a minimum set of monitoring stations that ‘covers’ the entire network for a given LOS, at a maximum degree of system invulnerability. The model developed extends a previous work of the authors through explicitly considering the deterioration and dilution of water quality as distributed with flow, and by taking into account the monitoring equipment capabilities to detect pollutant concentrations. The methodology is demonstrated using two example applications. 相似文献
70.
Buz A. McCain Anna G. Stefanopoulou Ilya V. Kolmanovsky 《Chemical engineering science》2008,63(17):4418-4432
We provide a semi-analytic solution to simplify an experimentally validated numeric realization of a two-phase, reaction-diffusion, distributed parameter model of the through-plane water distributions as they evolve inside polymer electrolyte membrane (PEM) fuel cell gas diffusion layers. The semi-analytic solution is then analyzed for stability and to gain insight into the dynamics of the equilibrium (steady-state) water distributions. Candidate distributions for vapor and liquid water are then identified which allow maximum membrane hydration while simultaneously avoiding voltage degradation that results from anode liquid water accumulation (flooding). The desired anode water distributions could be maintained via control of the anode channel conditions (boundary value control) with the ultimate goal to maximize the hydrogen utilization and prolong fuel cell life. 相似文献