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31.
In the fast-changing and multi-disciplinary practice of artful information visualization, the act of translating data into an image can be fraught with peril. There is considerable debate around modes of visualization and their relationships with the underlying data. This paper outlines the debate between the opposing ideologies through assessment of design considerations and comparisons of creative practice and visual analytics. The authors summarise the current nexus of influences and circumstances and proceed to formulate a set of guidelines for creative practitioners developing visualizations for Non-Expert Users (NEUVis).  相似文献   
32.
Air is filled in a cubic enclosure whose one vertical wall is isothermally heated and the opposite one is cooled while the other four walls are thermally insulated. A large coil is placed outside of this enclosure with the coil center coinciding with the cube center. An electric current in the coil generates a magnetic field to affect the convection of air, because the air contains oxygen whose magnetic susceptibility is exceptionally large among gases. The coil is further inclined around the X axis, which is horizontal and perpendicular to the hot and cold walls through the wall center. The heat transfer rate changes depending on the inclination angle. This system is studied numerically for convection for the following combination of parameters: Ra = 1.51 × 104, 9.06 × 104; Pr = 0.71; γ = 0 ? 100; xEuler = 0–π/2, where γ represents the strength of magnetic field and xEuler is the angle of inclination of the coil. For example, at Ra = 1.51 × 104 and γ = 30, the average Nusselt number 2.535 at xEuler = 0 increased to 2.823 at xEuler = π/2. This study suggests that the coil inclination affects the heat transfer rate extensively.  相似文献   
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34.
Itaconic acid (IA)–choline chloride (CC) deep eutectic solvents (DES) were prepared and characterized by NMR, TGA, and DSC. Poly(itaconic acid–co–bisacrylamide) hydrogels were synthesized by in situ polymerization‐crosslinking of the DES. For comparison, the hydrogels were also prepared in water under the same process conditions, that is, temperature, time, initial concentration of the monomer, the initiator, and N,N′‐methylenebisacrylamide (BAA) as the cross‐linking agent. Chemical structure of the polymers was proved by elemental analysis and FTIR. The values of insoluble gel fraction and water swelling of obtained hydrogels suggest that polymers prepared in DES have higher cross‐link density. Preliminary comparative studies of polymerization of IA in water and in DES medium indicated higher polymerization rate resulting from the presence of the choline salt, what might explain properties of the hydrogels prepared in DES. This study shows that DES can be used both as a solvent and catalyst in free‐radical polymerization processes. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40608.  相似文献   
35.
The present numerical investigation is concerned with the transient flow response in a reservoir model to periodic heating and cooling at the water surface. The numerical modelling reveals a stable stratification of the water body during the heating phase and an unsteady mixing flow in the reservoir during the cooling phase. It is shown that thermal instabilities play an important role in breaking up the residual circulation and initiating a reverse flow circulation in deep waters when the thermal conditions switch from heating to cooling. Further, if cooling is sufficiently strong, a clear undercurrent is formed, bringing cold water to the deep region of the reservoir. Moreover, heating from the water surface results in a stable large-scale convective roll which is clearly observed in the simulations. Understanding of the flow mechanisms pertinent to this problem is important for predicting the transport of nutrients and pollutants across reservoirs.  相似文献   
36.
Donor-acceptor (D-A) conjugated polymers are promising materials in optoelectronic applications, especially those forming ordered thin films. The processability of such conjugated macromolecules is typically enhanced by introducing bulky side chains, but it may affect their ordering and/or photophysical properties of the films. We show here the synthesis of surface-grafted D-A polymer brushes using alternating attachment of tailored monomers serving as electron donors (D) and acceptors (A) via coupling reactions. In such a stepwise procedure, alternating copolymer brushes consisting of thiophene and benzothiadiazole-based moieties with precisely tailored thickness and no bulky substituents were formed. The utilization of Sonogashira coupling was shown to produce densely packed molecular wires of tailored thickness, while Stille coupling and Huisgen cycloaddition were less efficient, likely because of the higher flexibility of D-A bridging groups. The D-A brushes exhibit reduced bandgaps, semiconducting properties and can form aggregates, which can be adjusted by changing the grafting density of the chains.  相似文献   
37.
Polymer brushes are classically defined and are to date employed as assemblies of macromolecules tethered at one end to a surface. The concept of preparing surface‐grafted gels by crosslinking such brushes is attractive since it gives rise to new opportunities related to the constraints present in this type of structure. Aiming at the development of nanostructured films possessing precisely adjustable chemical, mechanical, and optical properties, the present article describes the preparation of novel grafted layers based on gel‐brush/metal nanoparticle hybrids. These films were synthesized by surface‐initiated atom transfer radical polymerization of hydroxyethyl methacrylate with a small percentage of a crosslinker. The swelling, morphological, and mechanical properties of the gel‐brushes are shown to be highly dependent on the relative amount of crosslinker used. The gel‐brushes are subsequently used as matrixes for the controlled synthesis of silver nanoparticles with overall characteristics that are specifically tunable as a function of the macromolecular structure of the brush template.  相似文献   
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39.
The accuracy of proton therapy is partially limited by uncertainties that result from changing pathological conditions in the patient such as tumor motion and shrinkage. These uncertainties can be minimized with the help of a time-resolved range telescope. Monte Carlo methods can help improve the performance of range telescopes by tracking proton interactions on a particle-by-particle basis thus broadening our understanding on the behavior of protons within the patient and the detector. This paper compared the proton multiple coulomb scattering algorithms in the Monte Carlo codes MCNPX and Geant4 to well-established scattering theories. We focus only on beam energies associated with proton imaging. Despite slight discrepancies between scattering algorithms, both codes appear to be capable of providing useful particle-tracking information for applications such as the proton range telescope.  相似文献   
40.
We report herein a series of water-soluble analogues of previously described anticonvulsants and their detailed in vivo and in vitro characterization. The majority of these compounds demonstrated broad-spectrum anticonvulsant properties in animal seizure models, including the maximal electroshock (MES) test, the pentylenetetrazole-induced seizure model (scPTZ), and the psychomotor 6 Hz (32 mA) seizure model in mice. Compound 14 showed the most robust anticonvulsant activity (ED50 MES = 49.6 mg/kg, ED50 6 Hz (32 mA) = 31.3 mg/kg, ED50 scPTZ = 67.4 mg/kg). Notably, it was also effective in the 6 Hz (44 mA) model of drug-resistant epilepsy (ED50 = 63.2 mg/kg). Apart from favorable anticonvulsant properties, compound 14 revealed a high efficacy against pain responses in the formalin-induced tonic pain, the capsaicin-induced neurogenic pain, as well as in the oxaliplatin-induced neuropathic pain in mice. Moreover, compound 14 showed distinct anti-inflammatory activity in the model of carrageenan-induced aseptic inflammation. The mechanism of action of compound 14 is likely complex and may result from the inhibition of peripheral and central sodium and calcium currents, as well as the TRPV1 receptor antagonism as observed in the in vitro studies. This lead compound also revealed beneficial in vitro ADME-Tox properties and an in vivo pharmacokinetic profile, making it a potential candidate for future preclinical development. Interestingly, the in vitro studies also showed a favorable induction effect of compound 14 on the viability of neuroblastoma SH-SY5Y cells.  相似文献   
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