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61.
An analogue of disubstituted 3,4‐propylenedioxythiophenes, namely 3,3‐bis(cyclohexylmethyl)‐3,4‐dihydro‐2H‐thieno[3,4‐b][1,4]dioxepin (ProDOT‐CycHex2), was synthesized and its electrochemical polymerization was carried out successfully in an electrolyte solution of 0.1 M tetrabutylammonium hexafluorophosphate dissolved in a mixture of acetonitrile and dichloromethane (3/1: v/v). The corresponding polymer called PProDOT‐CycHex2 has a reduced band gap of 1.85 eV and an electrochromic property: blue/violet when neutralized and highly transparent when oxidized. Also, PProDOT‐CycHex2 film exhibited faster response time (0.7 s) and higher coloration efficiency (769 cm2/C) during oxidation when compared to its benzyl substituted analogue. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46214.  相似文献   
62.
The purpose of this paper is to introduce a novel UV‐cured interpenetrating polymer networked phase change materials (IPN‐PCMs), on which no article has been found in the so far published research. Maleated castor oil (MCO) was synthesized via maleinization reaction of castor oil with maleic anhydride. Organic–inorganic hybrid interpenetrating polymer networked (IPN) materials containing both cationic and radical sections and IPN‐PCMs containing tetradecanol, hexadecanol, and octadecanol were prepared. The chemical structure of MCO and organic–inorganic hybrid IPN‐PCMs were determined by using Fourier Transform Infrared Spectroscopy (FT‐IR). Differential scanning calorimetry (DSC) was used for examining the phase‐change behaviors of the materials. Thermal stability was investigated by thermogravimetric analysis (TGA). Moreover, the surface formation of the specimen was investigated by scanning electron microscopy (SEM). In conclusion, our study proved that because of their high latent heat storage scope and high thermal stability, the obtained organic–inorganic hybrid IPN‐PCMs could be used as thermal energy storage materials. POLYM. ENG. SCI., 58:870–875, 2018. © 2017 Society of Plastics Engineers  相似文献   
63.
This study aims to explore the ways of involving children with autism in participatory product design processes. Due to the impaired skills of children with autism, a key aspect of the process is to gain an understanding of the nature of the disorder and how these children interact with their social and material surroundings as well as their daily life problems. Considering this, a case study was conducted with children with autism, their parents and teachers, and also industrial design students in a public special education centre in ?zmir, Turkey. The design task was to reconsider the conventional trampoline design with respect to the needs of the sample group and the special education centre as well as the benefits it provides. The task was based on the patterns of behaviours, actions and movement. Observations, interviews and questionnaires were carried out, as well as collaborative meetings and discussion meetings. Through the case study, the findings provided insights into conducting a participatory process with children with autism, the roles of the participants, and the interaction and communication among them. Furthermore, participants’ attitude towards participatory design, the potential benefits of the design process, and innovations to benefit children with autism were explained.  相似文献   
64.
The molecule of azocalix[n]arene is a macrocyclic used effectively in the complexation of the heavy metal pollutants (like silver and mercury). In this work, our main aim is to prepare new chromogenic azocalix[n]arene molecules to elaborate an extractant with high extractant selectivity for metal ions able to detect this type of pollutant. The solvent extraction properties of four acetyls, four methyl ketones and four benzoyls derivatives from azocalix[4]arenes which were prepared by linking 4-ethyl, 4-n-butyl, 4-acetamid anilin and 2-aminothiazol to calix[4]arene through a diazo-coupling reaction, the alkaline earth (Sr2+) and the transition (Ag+, Hg2+, Co2+, Ni2+, Cu2+, Zn2+, Cd2+, Cr3+) metal cations have been determined by extraction studies with metal picrates. Both ketones are better extractants than esters, and show a strong preference for Ag+, while Cu2+ and Cr3+ are the most extracted cation with the esters. Both acetyl and benzoyl esters are good carriers for Ag+ and Hg2+.  相似文献   
65.
Single-molecule methods have matured into powerful and popular tools to probe the complex behaviour of biological molecules, due to their unique abilities to probe molecular structure, dynamics and function, unhindered by the averaging inherent in ensemble experiments. This review presents an overview of the burgeoning field of single-molecule biophysics, discussing key highlights and selected examples from its genesis to our projections for its future. Following brief introductions to a few popular single-molecule fluorescence and manipulation methods, we discuss novel insights gained from single-molecule studies in key biological areas ranging from biological folding to experiments performed in vivo.  相似文献   
66.
We propose the information regularization principle for fusing information from sets of identical sensors observing a target phenomenon. The principle basically proposes an importance-weighting scheme for each sensor measurement based on the mutual information based pairwise statistical similarity matrix between sensors. The principle is applied to maximum likelihood estimation and particle filter based state estimation. A demonstration of the proposed regularization scheme in centralized data fusion of dense motion detector networks for target tracking is provided. Simulations confirm that the introduction of information regularization significantly improves localization accuracy of both maximum likelihood and particle filter approaches compared to their baseline implementations. Outlier detection and sensor failure detection capabilities, as well as possible extensions of the principle to decentralized sensor fusion with communication constraints are briefly discussed.
Umut OzertemEmail:
  相似文献   
67.
The objective of this research paper is to assess the biosorption potential of almond shell residues for methyl orange dye. The pseudo-second-order kinetic model described the dye biosorption process with a good fitting. The relationship between the pseudo-second-order model constants and the biosorption performance was also evaluated. The equilibrium data fit well with the Langmuir isotherm model presenting that the biosorption was the monolayer coverage of dye on the biosorbent and the homogeneity of active sites for dye binding on the biosorbent surface. Based on the Langmuir model, a single-stage batch biosorber was also designed to predict the biosorbent mass for certain percentage dye removal. Besides, the standard Gibbs free energy change was also calculated to define the nature of biosorption process. These results revealed that the utilization of almond shell residues as dye biosorbent could be an interesting option from both environmental and economic point of view.  相似文献   
68.
In this study we consider the operational fixed job scheduling problem under working time limitations. The problem has several practical implications in both production and service operations; however the relevant research is scarce. We analyse pre-emptive and non pre-emptive versions of the problem and its special cases. We provide polynomial-time algorithms for some special cases. We show that the non pre-emptive jobs problem is strongly NP-hard, and propose a branch-and-bound algorithm that employs efficient bounding procedures and dominance properties. We conduct a numerical experiment to observe the effects of parameters on the quality of the solution. The results of our computational tests for the branch-and-bound algorithm reveal that our algorithm can solve the instances with up to 100 jobs in reasonable times. To the best of our knowledge our branch-and-bound algorithm is the first optimisation attempt to solve the problem.  相似文献   
69.
In this study, an integrated manufacturing system for technology-related companies whose products are experiencing continuous price decrease during the life cycle is studied for optimal procurement, production and delivery schedules over a finite planning horizon. The model considers the inventory cost both at manufacturing and at delivery from supplier. Since the price is continuously decreasing, a manufacturing firm delivers the finished goods in small quantities frequently. Frequent deliveries in small lots are effective to reduce the total cost of the supply chain. The key for high-tech industries is to reduce the inventory holding time since the component prices are continuously decreasing, and this can only be achieved by implementing an efficient supply chain. Therefore, the main purpose of this paper is to develop an integrated inventory model for high-tech industries in JIT environment under continuous price decrease over finite planning horizon while effectively and successfully accomplishing supply chain integration so that the total cost of the system is minimal. An efficient algorithm is developed to determine the optimal or near-optimal lot sizes for raw material procurement, and manufacturing batch under a finite planning horizon. Finally, the solution technique developed for the model is illustrated with numerical examples.  相似文献   
70.
9Ni–2Mg–Y alloy powders were prepared by arc melting, induction melting, mechanical alloying, solid state reaction and subsequent ball milling processes. The results showed that melting processes are not suitable for preparation of 9Ni–2Mg–Y alloy due to high losses of Mg and Y. Therefore, 9Ni–2Mg–Y alloy powder was prepared by three methods including: 1) mechanical alloying, 2) mechanical alloying + solid state reaction + ball milling, and 3) mixing + solid state reaction + ball milling. The prepared 9Ni–2Mg–Y alloy powders were compared for their catalytic effects on hydrogen desorption of MgH2. It is found that 9Ni–2Mg–Y alloy powder prepared by mechanical alloying + solid state reaction + ball milling method has a smaller particle size (1–5 μm) and higher surface area (1.7 m2 g−1) than that of other methods. H2 desorption tests revealed that addition of 9Ni–2Mg–Y alloy prepared by mechanical alloying + solid state reaction + ball milling to MgH2 decreases the hydrogen desorption temperature of MgH2 from 425 to 210 °C and improves the hydrogen desorption capacity from 0 to 3.5 wt.% at 350 °C during 8 min.  相似文献   
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