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311.
In this study, synthesis of insoluble polymeric ligand (L) and its transition metal complexes [Cu(L)Cl2]·2H2O (1), [Co(L)Cl2(H2O)2] (2) and [Ni(L)Cl2(H2O)2] (3), having the azomethine groups, were synthesized by the condensation reactions of the diamines and dialdehydes. The structural properties were characterized by the analytical and spectroscopic methods using by elemental analysis, Fourier Transform Infrared, Thermo Gravimetric Analysis, Powder X-ray Diffraction, magnetic susceptibility and Inductively Coupled Plasma. The solubilities of the synthesized polymeric materials were also investigated and found as insoluble some organic and inorganic solvents. Additionally, their catalytic performance was carried out for the esterification reaction of acetic acid and butyl acetate. The highest conversion rate is 75.75% by using catalyst 1. The esterification of butanol gave butyl acetate with 100% selectivity.  相似文献   
312.
Answer set programming (ASP) is a knowledge representation and reasoning paradigm with high-level expressive logic-based formalism, and efficient solvers; it is applied to solve hard problems in various domains, such as systems biology, wire routing, and space shuttle control. In this paper, we present an application of ASP to housekeeping robotics. We show how the following problems are addressed using computational methods/tools of ASP: (1) embedding commonsense knowledge automatically extracted from the commonsense knowledge base ConceptNet, into high-level representation, and (2) embedding (continuous) geometric reasoning and temporal reasoning about durations of actions, into (discrete) high-level reasoning. We introduce a planning and monitoring algorithm for safe execution of plans, so that robots can recover from plan failures due to collision with movable objects whose presence and location are not known in advance or due to heavy objects that cannot be lifted alone. Some of the recoveries require collaboration of robots. We illustrate the applicability of ASP on several housekeeping robotics problems, and report on the computational efficiency in terms of CPU time and memory.  相似文献   
313.
Solution blowing (SB) is a promising and scalable approach for the production of nanofibers. Air pressure, solution flow‐rate, and nozzle‐collector distance were determined as effective process parameters, while solution concentration was also reported as a material parameter. Here we performed a parametric study on thermoplastic polyurethane/dimethyl formamide (TPU/DMF) solutions to examine the effect of such parameters on the resultant properties such as fiber diameter, diameter distribution, porosity, and air permeability of the nanofibrous webs. The obtained solution blown thermoplastic polyurethane (TPU) nanofibers had average diameter down to 170 ± 112 nm, which is similar to that observed in electrospinning. However, the production rate per nozzle can be 20 times larger, which is primarily dependent on air pressure and solution flow rate (20 mL/h). Moreover, it was even possible to produce nanofibers polymer concentrations of 20%; however, this increased the average nanofiber diameter. The fibers produced from the TPU/DMF solutions at concentrations of 20% and 10% had average diameters of 671 ± 136 nm and 170 ± 112 nm, respectively. SB can potentially be used for the industrial‐scale production of products such as nanofibrous filters, protective textiles, scaffolds, wound dressings, and battery components. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43025.  相似文献   
314.
Anonymity technologies enable Internet users to maintain a level of privacy that prevents the collection of identifying information such as the IP address. Understanding the deployment of anonymity technologies on the Internet is important to analyze the current and future trends. In this paper, we provide a tutorial survey and a measurement study to understand the anonymity technology usage on the Internet from multiple perspectives and platforms. First, we review currently utilized anonymity technologies and assess their usage levels. For this, we cover deployed contemporary anonymity technologies including proxy servers, remailers, JAP, I2P, and Tor with the geo-location of deployed servers. Among these systems, proxy servers, Tor and I2P are actively used, while remailers and JAP have minimal usage. Then, we analyze application-level protocol usage and anonymity technology usage with different applications. For this, we preform a measurement study by collecting data from a Tor exit node, a P2P client, a large campus network, a departmental email server, and publicly available data on spam sources to assess the utilization of anonymizer technologies from various perspectives. Our results confirm previous findings regarding application usage and server geo-location distribution where certain countries utilize anonymity networks significantly more than others. Moreover, our application analysis reveals that Tor and proxy servers are used more than other anonymity techniques.  相似文献   
315.
Electrical and electronic equipments (EEE) have already begun to be accumulated at the garbage dumps. This garbage accumulation brings big danger to the environment and human health. That’s why one should look for exploring the ways to dispose of these wastes and emphasize the waste treatment strategies. Waste treatment strategies also contribute either to local or global economies by creating a new sector and employment opportunities, and by reducing use of scarce resources. In this paper, a linear programming technique for multidimensional analysis of preference (LINMAP) method for solving multi-attribute group decision making (MAGDM) problems with preference information on alternatives in fuzzy environment is developed. The aim is to develop a fuzzy LINMAP model for evaluation and select of a waste treatment strategy for EEE. Thus, three treatment strategy alternatives and eight criteria are determined. The best strategy is selected and the key criterion is found accordingly. The best alternative is found to be treating waste electrical and electronic equipments (WEEE) by reuse and recycling methods.  相似文献   
316.
317.
To acquire a competitive advantage in the expanding market, manufacturing companies should be able to manage their supply chain as much effective as possible. Measuring the supply chain performance is one of the main indicators of business success. Supply chain management (SCM) involves managing the flow of materials from suppliers to manufacturing units. This paper proposes a SCM model with performance measurement capabilities. The model is designed in such a way that it well suits to multi agent systems and related implementations. This paper highlights the components of the model especially pointing out the key parameters of performance indicators.  相似文献   
318.
S. Karaca  R. Bayrak 《Fuel》2003,82(8):1013-1019
In considering with morphological physicochemical transformations of the coal samples pyrolysed in CO2 atmosphere at different temperatures, the change of their adsorptive capacities have been investigated. It was seen that the change occurred in the monolayer adsorption capacities as parallel to morphological transformations of the coal surface is particularly connected with the amount of organic sulfur present in the coal matrix. Adsorption capacity is not affected from the contents of pyritic sulfur and ash of coal samples. The measurements of zeta potential of the pyrolysed coal samples also showed that pyrolysis modified the functional groups on surface of the coal, depending on the pyrolysis temperature.  相似文献   
319.
The effect of magnesium source on the fabrication of kotoite, Mg3B2O6, ceramic has been investigated by high temperature solid‐state reaction route based on the calcination of different magnesium sources, containing magnesium oxide, magnesium carbonate, magnesium sulfate, and magnesium nitrate with boric acid. The X‐ray powder diffraction results showed that single‐phase kotoite, Mg3B2O6, was synthesized using MgNO3.6H2O and 5 wt.% excess of H3BO3 powders as starting materials at 900°C for 48 hours. Mg3B2O6 obtained, is well crystallized, in orhorhombic crystal structure with lattice parameters of a = 5.399(9), b = 8.424(6), and c = 4.506(5) Å. Jana2006 refinement of this product shows excellent fit of the experimental data with software data, GOF= 1.33. The crystallite size of the product was calculated as 40.50 nm using Debye‐Scherrer's equation. The existence of BO3 triangles were detected by FTIR measurements of Mg3B2O6. The thermal properties were studied in the temperature range of 20°C to 1400°C by TG/DTA. The results showed that thermal stability of Mg3B2O6 is detected about 1380°C. Scanning electron microscopy was employed for observation of microstructure. The microstucture of obtained ceramic samples strongly depended on the magnesium source on the fabrication of Mg3B2O6 ceramic.  相似文献   
320.
In this study, temperature-concentration related rheological behavior of sour lemon juice concentrate (SLJC) were investigated. Lemons were squeezed, and lemon juices were obtained. SLJC samples were produced by two methods: atmospheric and vacuum conditions. The rheological properties of SLJC at 10, 20, 30, 40, and 50°C for each 31, 36, 41, 46, 51 °Bx were measured with rheometer. Firstly, it was determined that the SLJC showed Newtonian flow behavior at measured concentrations and temperatures. Then, viscosity of SLJC produced under vacuum conditions was determined higher than SLJC produced under atmospheric conditions. This difference was calculated statistically significant (p < .05). Furthermore, activation energy values of samples produced under atmospheric and vacuum conditions ranged between 13.6–24.0 kJ/mol and 9.0–17.9 kJ/mol, respectively. Finally, temperature-concentration dependent viscosity variations were modeled by surface equations, and the data predicted were transformed into images to provide visual analysis. It was determined by images that the viscosity change is proportional to concentration while inversely proportional to temperature. Ascorbic acid value was found higher under vacuum conditions than atmospheric conditions. In contrast, the HMF value was detected in low quantities under vacuum conditions.  相似文献   
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