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101.
International Journal of Speech Technology - The task of detecting and recognizing the state of emotion when dealing with textual data in the machine learning domain is not a straightforward path....  相似文献   
102.
Differential scanning calorimetry was used to detect adulteration of pure ghee with caprine body fat when added singly (at 5, 10 and 15%) and in combination with groundnut oil (GNO) (at 5, 10 and 15%). Samples were analysed for transition behaviour in terms of crystallising and melting curves. When compared to pure ghee, adulterated ghee samples showed a shift in the midrange temperature of thermal curves, indicating the presence of foreign fats. The results revealed that the detection of adulteration was possible at the lowest level of the study (5%), irrespective of the nature of the adulterants.  相似文献   
103.
Novel dihydroxy functional 3-arm star polymers were synthesized using a combination of atom transfer radical polymerization, ring opening polymerization, and click chemistry. The diols were characterized using gel permeation chromatography, Fourier transform infrared spectroscopy, and 1H NMR spectroscopy. The diols were incorporated into polyurethane coatings, which were characterized using differential scanning calorimetry, thermogravimetric analysis, pendulum hardness, water contact angle, and methyl ethyl ketone double rubs. The coatings showed an increase in the water contact angle values as the percentage of the polystyrene-based diol was increased. Similarly, the coatings with the poly(tert-butyl acrylate)-based diols showed a decrease in the glass transition temperature values with an increase in the diol content. It is expected that the use of controlled radical polymerization would allow for the synthesis of novel tailor-made functional polymers to achieve tunable coatings properties.  相似文献   
104.
105.
One of the main concerns of wireless sensor networks (WSNs) is to deliver useful information from data sources to users at a minimum power consumption due to constraints that sensor nodes must operate on limited power sources for extended time. In particular, achieving power-efficiency and multihop communication in WSN applications is a major issue. This paper continues on the investigation of a recently proposed Minimum-power Multiresolution Data Dissemination (MMDD) problem for WSNs (whose solution is considered here as a benchmark). We propose an ant-inspired solution to this problem. To the best of our knowledge, no attempts have been made so far in this direction. We have evaluated the performance of our proposed solution by conducting a variety of experiments and have found our solution to be promising in terms of total energy consumption in data dissemination.  相似文献   
106.
This paper presents a global-local (GL) method to simulate the interaction of ultrasonic guided waves with structural defects in isotropic and multilayered composite platelike structures. The GL method uses a full finite-element (FE) discretization of the defected region to properly represent wave diffraction phenomena and a suitable set of wave functions to simulate regions away from the joint. Displacement and stress continuity conditions are imposed at the boundary between the global and the local regions. The radiated wave field can be then calculated by using standard techniques (least-squares method). The novelty of the proposed approach over previous GL techniques is the use of semianalytical FE (SAFE) modeling for the “global” simulation. The SAFE method, which only requires the discretization of the waveguide’s cross section, allows handling complex structures (multilayered composites, arbitrary cross sections, etc.) in a computationally efficient manner. Applications of the GL method to damage quantification will be shown for the cases of notches in aluminum plates and delaminationlike defects in aircraft composite panels.  相似文献   
107.
Re-entry space vehicle necessities sharp leading edges for better aerodynamic performance and, hence, require advanced thermal protection materials with improved safety for crew members. Material possessing high thermal conductivity and oxidation resistance are desirable at nose cap and wings leading edge of spacecraft. Consequently, the thermal shock resistance improves due to reduced thermal gradient and stresses. ZrB2 has drawn strong impetus for futuristic space vehicles as thermal protection materials under extreme thermal environments. This study reviews the effect of the incorporation of non-carbonaceous and carbon additives on the thermal conductivity of ZrB2 ceramics and based composites. Several factors such as the purity of starting powder, initial particle size, amount of sintering aids, processing route, porosity, the grain size of ZrB2 matrix, distribution of secondary phases in the matrix and sinter density of the final composite, controls the overall thermal conductivity of ZrB2 based composites.  相似文献   
108.
Use of bio-oils in diesel engines results in increased NOx and smoke and reduced brake thermal efficiency. Dual-fuel engines can use a wide range of fuels mainly alcohols and yet operate with high thermal efficiency and simultaneous reduction of NO and smoke emissions. The present study aims to explore the effect of methanol–waste cooking oil (WCO) dual-fuel mode on performance and emission characteristics in a single cylinder Compression ignition (CI) engine producing 3.7 kW at 1,500 rpm. WCO was injected in the conventional injection system, replacing diesel as pilot fuel. Methanol was fumigated along with intake air using a variable jet carburetor, which was installed in the inlet manifold. The methanol was fumigated, and the energy share was varied for each load till the knock limit. Performance parameters like brake thermal efficiency (BTE) and emission parameters like HC, CO, NO, and smoke emissions were tested for various energy shares of methanol with WCO as a pilot fuel. The results show that an increase in methanol fumigation reduced BTE at lower loads. At 75% and 100% load conditions, BTE was higher with methanol addition. The maximum BTE was observed for 38% methanol share, which is about 11% higher, compared to WCO at 100% load condition. Methanol fumigation aided in the simultaneous reduction of NO and smoke emission, and the maximum reduction was occurred with 51% methanol share at 100% load condition. HC and CO emissions were higher at all load conditions with methanol fumigation.  相似文献   
109.
Polymer solar cells have been shown to degrade under X‐rays. Here, in situ polymer photovoltaic performance and recombination lifetimes are measured and it is found that charge accumulation is the primary reason for degradation of solar cells. This is affected by the mixing ratio of donor and acceptor in the bulk heterojunction. Both a quantitative understanding and the physical model of the degradation mechanism are presented. Understanding of the degradation mechanism is extended in polymer donor–acceptor bulk heterojunction systems to propose a material combination for making radiation hard diodes that can find important application in fields ranging from memory arrays to organic X‐ray detectors for medical imaging.  相似文献   
110.
Context: HIV-1 associated dementia (HAD) is an evolving disease in the category of neurological disorders.

Objective: Nifedipine-loaded solid lipid nanoparticles (SLNs) were developed and coated with Tween 80 to facilitate enhanced brain drug delivery for the treatment of HAD.

Materials and methods: SLNs were prepared using solvent injection method. Lipids consisted of tristearin, hydrogenated soya phosphatidylcholine (HSPC) (1.5:1 w/w). Nifedipine was model drug in this study. Tween 80 (0.5% v/v) was taken as key modulator. SLNs were characterized for particle shape, size, zeta potential, entrapment efficiency, in vitro drug release, DNA fragmentation, cytotoxicity potential and in vivo studies.

Results: The SLNs (plain and coated) were found to be in nanometric in size (~120?nm) with more than 70% entrapment efficiency. In vitro drug release profile reflected sustained release up to 48?h. Tween 80-coated SLNs showed higher percentage of DNA fragmentation in vitro and enhanced cell viability in sulforhodamine assay (rat cortical cells) as compared to plain drug and uncoated SLNs due to facilitated uptake of SLNs and reversal of P-gp efflux by virtue of Tween 80. Biodistribution study performed on vital organs, i.e. brain, heart, liver, spleen, lungs and kidney showed increased accumulation of Tween 80-coated SLNs in the brain.

Discussion and conclusion: Tween 80 enhanced localization of SLNs in the brain as compared to uncoated SLNs. This approach can be employed effectively to transport chemotherapeutics across the BBB for management of HIV-1 associated dementia and other ailments.  相似文献   
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