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1.
Passivated single damascene copper SiO2 damascene lines were evaluated in combination with TiSiN and Ta(N)/Ta diffusion barriers. Leakage current, breakdown and time-dependent dielectric breakdown properties were investigated on a wafer level basis for temperatures ranging between room temperature and 150 °C. It is found that the leakage performance of the wafers with a TiSiN barrier is better at room temperature, but at 150 °C the performance levels out with Ta(N)/Ta. Time-dependent dielectric breakdown measurements at 150 °C show that the lifetime of the interconnect is higher with the selected Ta(N)/Ta barrier than for TiSiN.  相似文献   
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The conditions of the preparation of formaldehyde/urea (F/U) resins have been supervised with the aim to reduce formaldehyde emission by influencing the ratio of methylene/dimethylene-ether-bridge linkages in the product. The most crucial point of this task is to keep the pH values of the reacting mixtures on the required level. The effect of formic acid, unevitably present in industrial formaldehyde solutions, was neutralized by applying a new buffer system, containing boric acid and ethylene glycol.  相似文献   
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Search engines are some of the most popular destinations on the Web—understandably so, given the vast amounts of information available to users and the need for help in sifting through online content. While the results of significant technical achievements, search engines are also embedded in social processes and institutions that influence how they function and how they are used. This special theme section of the Journal of Computer-Mediated Communication explores these non-technical aspects of search engines and their uses.  相似文献   
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Summary The hydrolytic degradation of Kevlar 49 fibers when dissolved in H2SO4 is characterized from (i) Fourier transform infrared (FTIR), CNH analyses and optical microscopy studies of insoluble crystals formed in the PPTA-H2SO4 dope and (ii) the rates of H2SO4-catalyzed hydrolysis of model compound aromatic amides. After hydrolysis of a PPTA amide linkage, the amide linkage adjacent to the freshly formed-COOH macromolecular end group rapidly hydrolyses resulting in the formation of terephthalic acid which then forms insoluble crystals in the PPTA-H2SO4 dope.Dedicated to Professor Dragutin Fle on the occasion of his 70th birthdaySupported in part by U.S. Department of Energy, LL National Laboratory under Contract W-7405-Eng-48  相似文献   
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Pellets containing metronidazole were produced in a centrifugal granulator, with hydroxypropylcellulose (Klucel LF®) as binding agent, and corn starch, microcrystalline cellulose (Vivapur 101®) and lactose as excipients. The wettability of the pharmaceutical powders was assessed by means of contact angle measurements, and the dispersive and polar surface energies were determined. The spreading coefficients, the work of adhesion and the work of cohesion were calculated and correlated with the pellet properties (friability, bulk and tapped density, and porosity). The aim was to investigate the role of the surface free energy of one- and two-component powder compositions in pellet production. The interactions between the particles were found to be connected with the measured pellet parameters. It was concluded that, in the course of the growth of the pellets, the particle sizes of the pharmaceutical powders and the interactions between them are important. If the work of cohesion of the binder is lower than the work of cohesion of the substrate and the work of adhesion, then the optimal amount of the binding agent is that which coats the particles uniformly in minimal quantity and in continuous layer.  相似文献   
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One of the major survival challenges of premature birth is production of lung surfactant. The lipid component of surfactant, dipalmitoyl PC (DPPC), increases in concentration in the period before normal term birth via a net shift in FA composition away from unsaturates. We investigated the influence of dietary DHA and arachidonic acid (AA) on lung FA composition and DPPC concentration in term and preterm baboons. Pregnant animals/neonates were randomized to one of four groups: breast-fed (B), term formula-fed (T), preterm formulafed (P), and preterm fed formula supplemented with DHA-AA (P+). Breast milk contained 0.68%wt DHA and the P+ group formula contained 0.61%wt DHA. In the preterm groups (P and P+), pregnant females received a course of antenatal corticosteroids. At the adjusted age of 4 wk, neonate lung tissue was harvested, and FA composition and DPPC were analyzed. Palmitate was ∼28%wt of lung total FA and no significant differences were found among the four treatment groups. In contrast, DPPC in the B group lung tissue was significantly greater than DPPC in the unsupplemented groups, but not compared with the P+ group. The B and P+ groups were not significantly different in DHA and AA, but were different compared with the unsupplemented (T, P) groups. These results indicate that LCP supplementation increases lung DHA and AA, without compromising overall lung 16∶0 or DPPC. The shift in FA composition toward greater unsaturation in the groups consuming LCP supported improved surfactant lipid concentration in preterm neonate lungs.  相似文献   
8.
In this paper, a methodology based on the combination of time series modeling and soft computational methods is presented to model and forecast bathtub‐shaped failure rate data of newly marketed consumer electronics. The time‐dependent functions of historical failure rates are typified by parameters of an analytic model that grabs the most important characteristics of these curves. The proposed approach is also verified by the presentation of an industrial application brought along at an electrical repair service provider company. The prediction capability of the introduced methodology is compared with moving average‐based and exponential smoothing‐based forecasting methods. According to the results of comparison, the presented method can be considered as a viable alternative reliability prediction technique. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
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In this paper we present Turk-2, a hybrid multi-modal chess player with a robot arm and a screen-based talking head. Turk-2 can not only play chess, but can see and hear the opponent, can talk to him and display emotions. We were interested to find out if a simple embodiment with human-like communication capabilities enhances the experience of playing chess against a computer. First, give an overview of the development road to multi-modal communication with computers. Then we motivate our research with a hybrid system, we introduce the architecture of Turk-2, we describe the human experiments and its evaluation. The results justify that multi-modal interaction makes game playing more engaging, enjoyable – and even more effective. These findings for a specific game situation provide yet another evidence of the power of human-like interaction in turning computer systems more attractive and easier to use.  相似文献   
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Controlled surface modification of the PDMS (polydimethylsiloxane) was developed and studied in this work to develop autonomous capillary-driven microfluidic system to be applied in bioanalytical devices. The characteristics of the PDMS surfaces were modified by embedding adequate surfactant molecules in the polymer matrix to be moved onto the free surface by diffusion. The change of the surface characteristics was studied considering the expected performance in autonomous biomicrofluidic applications and the influence on non-specific human blood protein binding also. The method was evaluated from technological aspects also, as the integrability of the microfluidic system, considering the previously published results critically. Compositions were defined to be adequate for fabrication autonomous capillary system with enhanced transport efficiency and moderated non-specific protein adsorption.  相似文献   
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