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11.
The purpose of this study was to determine whether there are changes in anterior and posterior glenohumeral translation after arthroscopic, nonablative, thermal capsuloplasty with a laser. Two anteriorly and two posteriorly directed loads were sequentially applied to the humerus of nine cadaveric glenohumeral joints, and anterior and posterior translation of the humerus on the glenoid was measured. The glenoid was rigidly fixed, and the glenohumeral joint was positioned simulating 90 degrees of shoulder abduction and 90 degrees of external rotation. Using the holmium:yttrium-aluminum-garnet laser, thermal energy was then applied to the anterior capsuloligamentous structures and anterior and posterior translation measurements were then repeated. The results showed a significant reduction in anterior and posterior translation after laser anterior capsuloplasty. Anterior translation decreased from 10.9 +/- 2.0 mm (mean +/- SEM) to 6.4 +/- 1.5 mm with the 15-N load; and from 13.4 +/- 2.1 mm to 8.9 +/- 1.8 mm with the 20-N load. Posterior translation decreased from 7.2 +/- 1.2 mm to 4.4 +/- 0.6 mm with the 15-N load and from 10.4 +/- 1.4 mm to 6.5 +/- 0.9 mm with the 20-N load. These results indicate that the holmium:yttrium-aluminum-garnet laser can be used to decrease glenohumeral joint translation and may be an effective treatment for glenohumeral joint instability.  相似文献   
12.
DOT ELISA was compared with RT-PCR and tissue culture to detect RSV from nasopharyngeal aspirates. DOT ELISA had diagnostic sensitivity and specificity of 65.62% and 93.92%, respectively. The results indicate that DOT ELISA can be used for screening detection of RSV from clinical specimens and is suitable for small laboratories in the provincial areas of developing countries.  相似文献   
13.
Ag deposited TiO2 was prepared by simple chemical reduction method and its photocatalytic efficiency was evaluated for the decolorization of methylene blue dye using pilot scale slurry type falling film reactors (FFR) under sunlight. The characterization of the prepared catalysts by XRD, TEM, EDAX, DRS and PL confirmed that silver, which acts as electron trap, was deposited over the TiO2 surface. The operational parameters, such as catalyst loading, concentration of the dye solution, pH of the slurry, addition of oxidizing agents and effect of different substrates, were optimized. The photocatalytic efficiency of Ag deposited TiO2 increased two-fold times than pure TiO2 and the maximum decolorization of dye was observed under acidic conditions. The reaction rate significantly increased with the addition of oxidizing agent H2O2. The ceramic tile as well as double skin reactor have higher photocatalytic efficiency than glass as substrate. In addition, Ag-deposited TiO2 photocatalyst could be easily recovered by simple sedimentation process and reused for repeated experimental cycles with more than 95% decolorization efficiency.  相似文献   
14.
15.
The removal of fluoride from drinking water by the method of adsorption on activated alumina is found superior than other defluoridation techniques mostly due to the strong affinity between aluminium and fluoride. Dissolution of aluminium from the alumina surfaces into its free and hydroxide ions in the aqueous medium is reported to be very low, but the presence of high fluoride concentrations may increase its solubility due to the formation of monomeric aluminium fluoride and aluminium hydroxyl fluoride complexes. An Activated Alumina Defluoridation Model Simulator (AAD) has been developed to represent fluoride adsorption on the basis of the surface complexation theory incorporating aspects of aluminium solubility in presence of high fluoride concentrations and pH variations. Model validations were carried out for residual aluminium concentrations in alumina treated water, by conducting a series of batch fluoride adsorption experiments using activated alumina (grade FB101) treating fluoride concentrations of 1-10 mg/L, at varying pH conditions. The total residual aluminium in the defluoridated water is due to presence of both dissolved and precipitated Al-F complexed forms. The Freundlich adsorption isotherm was found fit for fluoride adsorption capacity versus residual fluoride concentrations for pH = 7.5, and the relationship is given by the linearised equation log (x/m) = log k + (1/n) log Ce with values of k = 0.15 mg/g and 1/n = 0.45 indicating favorable adsorption. The relationship is linear in the region of low fluoride concentrations, but as concentrations of fluoride increased, the formation of the dissolved AlF30 complexes was favored than adsorption on alumina, and hence makes the isotherm nonlinear. The AAD simulations can predict for operating fluoride uptake capacity in order to keep the residual aluminium within permissible limits in the alumina treated water.  相似文献   
16.
At present, the symmetry of the order parameter in the high temperature superconductor YBCO is quite controversial. Recent experiments using SQUIDs and Josephson junctions appear to support competing theories, with some experiments supporting a dx2–y2 pairing symmetry for the order parameter and others a s-wave pairing symmetry. We note that a number of factors such as trapped flux, magnetic field gradients and SQUID asymmetries could lead such measurements astray. We use a Scanning SQUID Microscope and a time-reversal invariance test to resolve these experimental problems. We find the order parameter in YBCO has a time-reversal invariant dx2–y2 symmetric component. We estimate the amplitude of anyimaginary s-wave symmetric component to be less than 4% and anyreal s-wave component to be less than 82%.  相似文献   
17.
Transformation of programs for fault-tolerance   总被引:2,自引:0,他引:2  
In this paper we describe how a program constructed for afault-free system can be transformed into afault-tolerant program for execution on a system which is susceptible to failures. A program is described by a set of atomic actions which perform transformations from states to states. We assume that a fault environment is represented by a programF. Interference by the fault environmentF on the execution of a programP can then be described as afault-transformation which transformsP into a program (P). This is proved to be equivalent to the programPP F , whereP F is derived fromP andF, and defines the union of the sets of actions ofP andF P . A recovery transformation transformsP into a program (P) =PR by adding a set ofrecovery actions R, called arecovery program. If the system isfailstop and faults do not affect recovery actions, we have ((P))=(P)R=PP F R We illustrate this approach to fault-tolerant programming by considering the problem of designing a protocol that guarantees reliable communication from a sender to a receiver in spite of faults in the communication channel between them.  相似文献   
18.
Nisanth  A.  Suja  K. J.  Seena  V. 《Microsystem Technologies》2021,27(1):251-261
Microsystem Technologies - Piezoelectric vibrational energy harvester (PVEH) suits best for harvesting vibrational energy from the environment due to the simplicity in design, operation, and...  相似文献   
19.
Micro electro mechanical system are usually defined as highly miniaturized devices combining both electrical and mechanical components that are fabricated using integrated circuit batch processing techniques. Silicon based stacked diaphragm structure is a combination of silicon-di-oxide and the silicon layer. This work brings out a new approach of finding the sensitivity of stacked diaphragm with respect one of the important parameters like deflection. The sensitivity is also evaluated under thermal effect and, the analytical model developed for the same closely matches with the finite element model. The doping concentration of 1017cm-3, in which single silicon shows maximum sensitivity has been selected and an increase in the sensitivity is observed on using a stacked diaphragm structure. The stacked diaphragm structure is designed, simulated and compared with existing single diaphragm design with respect to diaphragm deflection and sensor output voltage for linearity over a wider range. The effect of the buried oxide in the stacked diaphragm structure is also considered in this work. The work in this paper provides a mathematical expression for realizing the effect of boron implanted resistors on the stacked diaphragm structure. The simulation result reported in the literature evaluates the deflection at a particular temperature but the new analytical model developed in this paper evaluates the sensitivity of the diaphragm over a temperature range.  相似文献   
20.
Experimental screening of large sets of compounds against macromolecular targets is a key strategy to identify novel bioactivities. However, large-scale screening requires substantial experimental resources and is time-consuming and challenging. Therefore, small to medium-sized compound libraries with a high chance of producing genuine hits on an arbitrary protein of interest would be of great value to fields related to early drug discovery, in particular biochemical and cell research. Here, we present a computational approach that incorporates drug-likeness, predicted bioactivities, biological space coverage, and target novelty, to generate optimized compound libraries with maximized chances of producing genuine hits for a wide range of proteins. The computational approach evaluates drug-likeness with a set of established rules, predicts bioactivities with a validated, similarity-based approach, and optimizes the composition of small sets of compounds towards maximum target coverage and novelty. We found that, in comparison to the random selection of compounds for a library, our approach generates substantially improved compound sets. Quantified as the “fitness” of compound libraries, the calculated improvements ranged from +60% (for a library of 15,000 compounds) to +184% (for a library of 1000 compounds). The best of the optimized compound libraries prepared in this work are available for download as a dataset bundle (“BonMOLière”).  相似文献   
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