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731.
The effects of pH and ionic strength on the thermal gelation of brown trout myofibrils from white and red muscles were analysed by thermal scanning rheometry. The highest gelation ability was obtained at low pH (around 5.6) whatever the ionic strength. No effect of ionic strength was observed at pH 5.6; however, at pH 6.0, lowering the salt (KCl) concentration to 0.3 M or less improved the characteristics of the gels formed. The effects of pH and ionic strength on myofibrils from both muscle types appeared to be similar, but red muscle proteins were less sensitive to changes in their physicochemical environment. Consequently, the differences between muscle types appeared to be dependent on pH and ionic strength. Solubility measurements revealed large differences between muscle types and between different pH values. Ultrastructural observations confirmed that different kinds of gels were formed depending on the physicochemical conditions and muscle type origin. © 2002 Society of Chemical Industry  相似文献   
732.
733.
The design of science‐based products (SBP) combines three main issues: exploring a functional space, producing scientific knowledge about key phenomena related to the concept and ensuring manageability of the project. Literature on the subject generally considers the three issues to be irreconcilable, on the grounds that a project involving functional exploration and phenomenological exploration is unmanageable. However, based on two SBP cases, we show that this apparent unmanageability is mainly a result of the lack of a relevant managerial model for the interpretation of the observations. We introduce the notion of ‘design space’ as a collective working place where designers can act to learn about what they want to learn (for their overall design process). We show that the design of an SBP is managed as a sequence of design spaces.  相似文献   
734.
Two experiments examined the structure of individual differences in mice by means of tasks that produced significant acquisition within 1 session. In Experiment 1, 5 cognitive tasks-detour, winshift, olfactory discrimination, fear conditioning, and operant acquisition-were used in conjunction with two control procedures: an open field and a light- dark test. In Experiment 2, some modifications were made to the tasks used in the 1st experiment, and 3 new tasks were used in conjunction with the same control procedures. The battery consisted of 5 learning tasks: detour, Hebb-Williams, radial maze, olfactory foraging, and fear conditioning. Results of both experiments indicate that when cognitive tasks and control procedures were included in principal-components analyses most of the variance attached principally to individual tasks rather than to a general component as is found typically in human cognitive batteries. When control procedures were eliminated, there was better evidence for the presence of a general cognitive factor, particularly in Experiment 2. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
735.
A method to determine the wall thickness and conductivity of non-magnetic tubes using eddy-current measurements is presented. The equivalent circuit impedance formulae for an infinitely long solenoid with a conductive tube inside are derived. This simplified theoretical model is applied to calculate the tube wall thickness using the measured resistance and inductance of a real long coil with a long tube inside. In order to take into account the coil's finite length, an apparent fill factor is introduced. The last parameter is determined experimentally and used as the fill factor in the theoretical model. We report experimental tests for brass and copper tubes of nominal diameters in the range 12–20 mm and nominal thickness from 0.9 to 2.5 mm. An uncertainty of the wall thickness measurements typically within 2% is obtained.  相似文献   
736.
The purpose of this research was the investigation of the ozonation of sludge as a method to improve anaerobic digestion performance in a chemically enhanced primary treatment facility. Batch tests were conducted to evaluate the effect of ozonation on the physicochemical characteristics of both primary and digested sludge. Then, the performance of semi-continuous anaerobic digesters in combination with ozone treatment was investigated (pre-ozonation and post-ozonation). Ozonation of primary sludge did not increase the soluble COD nor the biodegradable COD, but resulted in the mineralization of a fraction of the organic matter into CO2. However, the ozonation of anaerobic digested sludge resulted in an increase in soluble COD and biodegradable COD and in a small level of mineralization at the dose of 90 mg O3/g COD. Pre-ozonation of primary sludge was not effective in enhancing the performance of the anaerobic digester. The coupling of ozonation and anaerobic digestion by means of the post-ozonation of digested sludge was found to be effective in improving methane production (+16%), for COD removal efficiency and for the dewaterability of anaerobic digesters compared to the control digester.  相似文献   
737.
For semicrystalline thermoplastic parts it is well known that increasing isothermal holding temperature can affect inner component properties, respectively, crystalline structure (e.g., morphology, degree of crystallization, crystal modification, etc.) and, therefore, resulting global component properties such as hardness and wear. Nevertheless, in literature there is no explicit focus on the effect of isothermal holding time during dynamically tempered injection molding process. In this article, semicrystalline microcomponents have been injection molded by varying isothermal holding time within the material's crystallization temperature area. As materials, POM‐C, as a material with relatively high crystallization kinetic, and PA 12, as a material with medium crystallization kinetic, were used. To evaluate the effects on hardness and wear, nanoindentation measurements as well as pin‐on‐disc wear tests were performed. Results show that for fast crystallizing POM‐C an isothermal holding step has no significant influence on inner component and resulting global component properties. For slower crystallizing PA 12, however, the morphology and the degree of crystallization could be influenced and, as a result, hardness could be increased by 21% while wear could be reduced by 30%. POLYM. ENG. SCI., 57:121–128, 2017. © 2016 Society of Plastics Engineers  相似文献   
738.
The laser heated pedestal growth (LHPG) technique has been applied to grow undoped and doped Lu2SiO5:Ce3+ (LSO:Ce) single crystals fibers with stable diameter. The starting cerium concentration in the melt was [0.05–1] at.%. The thermal and growth conditions allowing pulling transparent single crystals fiber’s were optimised. The fibers have been grown under N2 + 1% O2 atmosphere (1 bar). The Ce3+ segregation coefficient is 0.28 greater than the crystal grown by Czochralski technique. The as grown fibers demonstrated scintillating properties.  相似文献   
739.
A universal accelerated test for both alkali-silica and alkali-carbonate reactivity was proposed based on extensive comparative studies on existed Accelerated Mortar Bar Test (AMBT), (e.g., ASTM C1260, CSA A23. 2–25A, RILEM TC191-ARP-AAR02) and Chinese accelerated procedures. A single size fraction of 2.5–5.0 mm aggregate particles is used in the test instead of five-graded requirements in the AMBT, and 0.15–0.80 mm fine particles for ASR, 5–10 mm particles for ACR in existed Chinese accelerated tests. Three short-fat bars, 40 × 40 × 160 mm, made at fixed cement-aggregate ratio of 1:1, and water-cement ratio of 0.33 are used and the length change of the bars is monitored till 28 days in 1 M NaOH solution at 80°C after being soaked in 80°C water for 24 h. Over 40 kinds of aggregates from various origins, which include both ASR and ACR aggregates and show a broad range of reactivity levels in the concrete prism test (CPT), were used to evaluate the reliability of the new test in this study. Experimental results indicate that, for ASR aggregates, the new test gives a better indication than the AMBT does of both the reactive/nonreactive characteristic and reactive levels of almost all tested aggregates based on an acceptance criteria of 0.093% at 14 days, although some very highly reactive aggregates show low expansions relative to the CPT. The “abnormal” low expansion of some highly reactive aggregate in the test is mainly due to the rapid formation and loss of fair amount of low viscosity ASR product into the soaking alkali solution. The results on some typical ACR aggregates usually undetected by the AMBT show that the new test gives the same outcome as using 5–10 mm particles in the Chinese Accelerated Concrete Microbar Test for ACR aggregates and is in agreement with the CPT, which suggests that it has good potentials to be used for ACR aggregate when an expansion criteria of 0.1% after 28 days is used.  相似文献   
740.
浪漫玫瑰梦     
本文所称"玫瑰",译自原作法文中的rose,实则为国内统称的月季。作者Benoit Hochart先生是一位十足的玫瑰迷,当知道法国招聘世博玫瑰园艺师的消息后,积极申请,经过层层筛选,得以成为上海世博会法国玫瑰园的"主人"。在世博会城市最佳实践区的法国罗阿大区内,玫瑰园和城市照明、美食一起,并列为展区三大亮点,以视觉、嗅觉和味觉为世博献上饕餮盛宴。  相似文献   
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