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1.
Extracellular vesicles (EVs) are membranous structures, which are secreted by almost every cell type analyzed so far. In addition to their importance for cell-cell communication under physiological conditions, EVs are also released during pathogenesis and mechanistically contribute to this process. Here we summarize their functional relevance in asthma, one of the most common chronic non-communicable diseases. Asthma is a complex persistent inflammatory disorder of the airways characterized by reversible airflow obstruction and, from a long-term perspective, airway remodeling. Overall, mechanistic studies summarized here indicate the importance of different subtypes of EVs and their variable cargoes in the functioning of the pathways underlying asthma, and show some interesting potential for the development of future therapeutic interventions. Association studies in turn demonstrate a good diagnostic potential of EVs in asthma.  相似文献   
2.
Transition metal oxyhydroxides have been used as promising electrocatalysts for water splitting however, their catalytic activity is restricted due to low surface area and poor conductivity. Herein, we report novel composite FeOOH@ZIF-12/graphene composite as electrocatalyst for water oxidation, whereby ZIF-12 provide extra surface for the FeOOH dispersion whilst graphene act as excellent electron mediator. The composite shows a low overpotential value of 291 mV to attain a current density of 10 mA cm?2 and a low Tafel slope value of 78 mV dec?1. The catalyst offers a maximum current density of 101 mA cm?2, while it gives a turnover frequency (TOF) value of 0.031 s?1 at an overpotential of 291 mV only. The excellent activity and remarkable stability of composite is attributed to highly conductive and porous support.  相似文献   
3.
1. Intracerebroventricular (i.c.v.) injection of choline (25-150 micrograms) increased blood pressure in rats made acutely hypotensive by haemorrhage. Intraperitoneal administration of choline (60 mg kg-1) also increased blood pressure, but to a lesser extent. Following i.c.v. injection of 25 micrograms or 50 micrograms of choline, heart rate did not change, while 100 micrograms or 150 micrograms i.c.v. choline produced a slight and short lasting bradycardia. Choline (150 micrograms) failed to alter the circulating residual volume of blood in haemorrhaged rats. 2. The pressor response to i.c.v. choline (50 micrograms) in haemorrhaged rats was abolished by pretreatment with mecamylamine (50 micrograms, i.c.v.) but not atropine (10 micrograms, i.c.v.). The pressor response to choline was blocked by pretreatment with hemicholinium-3 (20 micrograms, i.c.v.). 3. The pressor response to i.c.v. choline (150 micrograms) was associated with a several fold increase in plasma levels of vasopressin and adrenaline but not of noradrenaline and plasma renin. 4. The pressor response to i.c.v. choline (150 micrograms) was not altered by bilateral adrenalectomy, but was attenuated by systemic administration of either phentolamine (10 mg kg-1) or the vasopressin antagonist [beta-mercapto-beta,beta-cyclopenta-methylenepropionyl1, O-Me-Tyr2,Arg8]-vasopressin (10 micrograms kg-1). 5. It is concluded that the precursor of acetylcholine, choline, can increase and restore blood pressure in acutely haemorrhaged rats by increasing central cholinergic neurotransmission. Nicotinic receptor activation and an increase in plasma vasopressin and adrenaline level appear to be involved in this effect of choline.  相似文献   
4.
Expressions for the calculation of the parameters of self-diffusion in a crystal of simple substance at temperatures close to absolute zero are derived. It is established that, in “loose” crystal structures (with the first coordination number below 12), the amount of atoms involved in diffusion motion exceeds the number of vacant sites in the crystal lattice at T=0 K. The results of calculations of the vacancy and diffusion parameters at T=0 K for ten cryocrystals show that the phenomenon of “nonvacancy self-diffusion at T=0 K” can take place only in bcc helium.  相似文献   
5.
Enhanced Image Detection on an ARM based Embedded System   总被引:2,自引:0,他引:2  
This paper presents a new technique for thedetection of Integrated Circuits within images of Printed Circuit Boards autonomouslyand without the need to be assisted by CAD data. The technique is a key partof a suite of algorithms targeted for an embedded System On Chip architecturebased on the ARM7 platform for real time detection of PCB images for diagnosticpurposes. The technique has a significant reduction in complexity when comparedto conventional approaches such as the Hough Transform. The reduction in complexitymakes the approach ideal for an embedded vision application suchas the one described in this paper. This paper presents the technique, thetarget embedded architecture and results showing the reduction in complexitywhen compared to a Hough Transform.  相似文献   
6.
. A knowledge-based expert system was developed to aid in the selection of the type of dam. The dam type selector expert system (DTSA ES) was designed to determine the type of dam on the alluvium foundations. Detailed expert knowledge is required to estimate the type of dam and to develop an expert system. The DTSA ES utilizes rules of thumb used by an expert for determining the selection of the type of dam. The DTSA ES was developed using a shell program. The expert system was tested on several dam sites in order to validate the decision obtained. The use of this expert system, containing knowledge about the selection of dam type, can be helpful to students, potential owners or contractors in selecting dam types. The current prototype always needs additional parameters for more detailed analyses of new developments. However, the current DTSA ES is designed to include existing information about dam types.  相似文献   
7.
Neural Computing and Applications - Lung cancer is a deadly disease if not diagnosed in its early stages. However, early detection of lung cancer is a challenging task due to the shape and size of...  相似文献   
8.
1.  Intense passage of the sediment deposits washed from the upstream stretches of the reservoir through the cut was observed. In the cut itself or in the immediate vicinity of its outlet, 13,000 m3 of sediments was deposited, the remainder was discharged by the through-flow into the downstream pool.
2.  The cut made was not curvilinear in plan as was intended, and therefore its expected intensive erosion by the flow did not occur. The exception was the inlet stretch of the cut, where its erosion and widening by about 10 m occurred.
3.  An increase of the cross-sectional area of the reservoir due to the cut leads to some decrease of the level of the flushing flow in the main channel and increases its slope on the upstream stretch of the reservoir, increasing the flow velocity and effectiveness of erosion of the sediments. Furthermore, the directions of the flow velocities partially changed in the region of the cut, which intensified the effect of erosion of the sediments.
4.  Gradual erosion of the island of sediment deposits cut off by the cut from the left-bank mass of sediments was observed during flushing and subsequent operation of the reservoir.
5.  It is better to use diesel dredges for making cuts, which, with their self-contained power supply makes it possible to operate on any stretch of the reservoir at a sufficient distance from the bank.
6.  The cost effectiveness of combined removal of sediments can be estimated by comparing the cost of conducting it with the cost of removing sediments by hydraulicking as the cheapest of the presently known methods. For conditions of the Chiryurt reservoir the effectiveness was 0.9 ruble/m3 of sediments being removed for the particular flushing under consideration.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 8, pp. 34–37, August, 1989.  相似文献   
9.
Turkish lignite can be used as a new adsorption material for removing some toxic metals from aqueous solution. The adsorption of lignite (brown young coals) to remove copper (Cu2+), lead (Pb2+), and nickel (Ni2+) from aqueous solutions was studied as a function of pH, contact time, metal concentration and temperature. Adsorption equilibrium was achieved between 40 and 70 min for all studied cations except Pb2+, which is between 10 and 30 min. The adsorption capacities are 17.8 mg/g for Cu2+, 56.7 mg/g for Pb2+, 13.0 mg/g for Ni2+ for BC1 (Ilg?n lignite) and 18.9 mg/g for Cu2+, 68.5 mg/g for Pb2+, 12.0 mg/g for Ni2+ for BC2 (Beysehir lignite) and 7.2 mg/g for Cu2+, 62.3 mg/g for Pb2+, 5.4 mg/g for Ni2+ for AC (activated carbon). More than 67% of studied cations were removed by BC1 and 60% BC2, respectively from aqueous solution in single step. Whereas about 30% of studied cations except Pb2+, which is 90%, were removed by activated carbon. Effective removal of metal ions was demonstrated at pH values of 3.8–5.5. The adsorption isotherms were measured at 20 °C, using adsorptive solutions at the optimum pH value to determine the adsorption capacity. The Langmuir adsorption isotherm was used to describe observed sorption phenomena. The rise in temperature caused a slight decrease in the value of the equilibrium constant (Kc) for the sorption of metal ions. The mechanism for cations removal by the lignite includes ion exchange, complexation and sorption. The process is very efficient especially in the case of low concentrations of pollutants in aqueous solution, where common methods are either economically unfavorable or technically complicated.  相似文献   
10.
This paper presents a new adaptive algorithm that aims to control the exploration/exploitation trade-off dynamically. The algorithm is designed based on three-dimensional cellular genetic algorithms (3D-cGAs). In this study, our methodology is based on the change in the global selection pressure induced by dynamic tuning of the local selection rate. The parameter tuning of the local selection method is a way to define the global selection pressure. A diversity speed measure is used to guide the algorithm. Therefore, the integration of existing techniques helps in achieving our aims. A benchmark of well-known continuous test functions and real world problems was selected to investigate the effectiveness of the algorithm proposed. In addition, we provide a comparison between the proposed algorithm and other static and dynamic algorithms in order to study the different effects on the performance of the algorithms. Overall, the results show that the proposed algorithm provides the most desirable performance in terms of efficiency, efficacy, and speed for most problems considered. The results also confirm that problems of various characteristics require different selection pressures, which are difficult to be identified.  相似文献   
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