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91.
A simple method, supplying water with Jatropha oil, was proposed to enhance the conversion of selectivity of lower olefins over zeolite catalysts, H-ZSM-5 and SAPO-11. The yield of lower olefins was as high as 54 C mol%, and the selectivity for lower olefins reached 58 C mol%. The optimum condition on catalytic conversion of jatropha oil was 600 °C of reaction temperature, 3.0 s of contact time and 0.7 of water fraction with SAPO-11. The presence of water effectively suppressed the progress of Diels-Alder and hydrogen transfer reaction probably due to the reduced number of acid sites.  相似文献   
92.
This paper investigates people’s social acceptance of a childcare support robot system and compares it with existing childcare technologies (anesthesia during labor and baby food, i.e. processed food and formula milk) through web-based questionnaires between Japan and USA and a field study in Japan. We investigated social acceptance through four scales: intention to use, safety and trustworthiness, negative attitudes, and decreasing workload. For this paper, our participants included 400 people (200 from each country) in Japan and USA located through a web-based survey who answered questionnaires about the four scales to investigate their social acceptance of childcare support technologies. Our web-based survey results indicate that our system’s concept was evaluated lower than current childcare support technologies in both Japan and USA. We also conducted a field trial with 30 additional people in Japan and through their actual experiences investigated their evaluations of the prototype of our childcare support robot system.  相似文献   
93.
Laser range finders (LRF’s) are non-invasive sensors which can be used for high-precision and anonymous tracking of pedestrians in social environments. Such sensor networks can be used in robotics to assist in navigation and human–robot interaction. Typically, multiple LRF’s are used together for such tasks, and the relative positions of these sensors must be precisely calibrated. We propose a technique for estimating relative LRF positions using observations of social groups in the pedestrian flow as keypoint features for determining coarse estimates of relative sensor offsets. The most likely offset is estimated using a generalized Hough transform and used to identify sets of possible shared observations of individual pedestrians between pairs of sensors. Outliers are rejected using the RANSAC technique, and the resulting shared observations from each sensor pair are combined into a constraint matrix for the sensor network, which is solved using least-squares minimization. Results show calibration accuracy of sensor positions within 34?mm and 0.51°, and an analysis of pedestrian data collected from ubiquitous networks in three public and commercial spaces shows that the proposed calibration technique enables pedestrian tracking within 11?cm accuracy.  相似文献   
94.
How to improve adhesion between poly(oxybenzoate‐co‐oxynaphthoate) (Vecstar OC and FA films) and copper metal by Ar, O2, N2 and NH3 plasma modification was investigated. The mechanism of adhesion improvement is discussed from the viewpoint of chemical and physical interactions at the interface between the Vecstar film and copper metal layer. The adhesion between Vecstar OC film and copper metal was improved by chemical rather than physical interactions. Polymer chain end groups that occur at Vecstar OC film surfaces contribute effectively to adhesion. This improvement in adhesion is due to interactions between copper metal and O?C groups formed by plasma modification. Aggregation of the O?C groups to the copper metal/Vecstar OC film interface is a key factor for good adhesion. From this aspect, heat treatment of plasma‐modified Vecstar OC films on glass plates is effective in the aggregation, and the peel strength for the copper metal/Vecstar OC film system reached 1.21 N (5 mm)?1. Copyright © 2009 Society of Chemical Industry  相似文献   
95.
Gluten peptides are prepared using limited hydrolysis of wheat gluten, resulting in improved solubility and physico-chemical properties. In general, the hydrolysis is performed using a batch-wise process. In this study, we developed a bioreactor system that can continuously produce gluten peptides with foaming properties. Two kinds of acid protease, pepsin and rapidase, were immobilized on porous chitosan beads. The partial deamidation of gluten in advance increased initial velocity of hydrolysis by immobilizing protease and also worked to enhance foaming properties. A packed-bed reactor filled with immobilized protease was designed, and operating parameters were optimized. The optimized conditions were as follows: pH, 3.0; temperature, 40 °C; substrate concentration, 40 mg/ml; and space velocity, 2.0 h–1. Based on these results, a bench-scale reactor was manufactured to determine the stability of continuous operation. The half-life of the reactor was approximately 45 days, and both productivity and quality were stable and excellent.  相似文献   
96.
The impact of different spallation models and parametrisation of nucleon–nucleus interactions in the particle transport code PHITS on the nuclear characteristics of an accelerator-driven system (ADS) is investigated. Cut-off neutrons below 20 MeV calculated using the default option of the current spallation model (i.e. Liège intranuclear cascade (INC) model version 4.6, INCL4.6) are found to be 14% less than those calculated by the old spallation model (i.e. Bertini INC model). This decrease increases the proton beam current that drives the 800-MW thermal power and impacts various ADS parameters, including material damage, nuclear heating of the proton beam window and the inventory of spallation products. To validate these options based on the ADS neutronics design, we conduct benchmark calculations of the total and non-elastic cross sections, thick target neutron yields and activation reaction rate distributions. The results suggest that Pearlstein–Niita systematics, which is a default option of the nucleon–nucleus interaction parametrisation, would be the best option and that Bertini INC is better suited for cut-off neutrons than INCL4.6. However, because of the difficulty in making a definite conclusion on the spallation models, we conclude that relatively large uncertainty in the cut-off neutrons, which is the difference between the two spallation models (i.e. 14%), should be considered.  相似文献   
97.
In this paper, we present a robust 3D human-head tracking method. 3D head positions are essential for robots interacting with people. Natural interaction behaviors such as making eye contacts require head positions. Past researches with laser range finder (LRF) have been successful in tracking 2D human position with high accuracy in real time. However, LRF trackers cannot track multiple 3D head positions. On the other hand, trackers with multi-viewpoint images can obtain 3D head position. However, vision-based trackers generally lack robustness and scalability, especially in open environments where lightening conditions vary by time. To achieve 3D robust real-time tracking, here we propose a new method that combines LRF tracker and multi-camera tracker. We combine the results from trackers using the LRF results as maintenance information toward multi-camera tracker. Through an experiment in a real environment, we show that our method outperforms toward existing methods, both in its robustness and scalability.  相似文献   
98.
The authors are studying a diagnostic method of a PV power generating system. We consider that the change of IV characteristics can be utilized for the diagnosis. However, the report on the change of IV characteristics is very little. In this paper, we investigate the relation between the output lowering due to shaded PV cells and the change of IV characteristics, utilizing the computer simulation. It was proven from the simulation that IV characteristics are changed by the condition of the shadow, which covered the module. The change of IV characteristics of a PV module with shaded PV cells is discussed by the shift of the avalanche breakdown voltage of shaded PV cells.  相似文献   
99.
In this study, we prepared injectable collagen microspheres for the sustained delivery of recombinant human vascular endothelial growth factor (rhVEGF) for tissue engineering. Collagen solution was formed into microspheres under a water-in-oil emulsion condition, followed by crosslinking with water-soluble carbodiimide. Various sizes of collagen microspheres in the range of 1–30 μm diameters could be obtained by controlling the surfactant concentration and rotating speed of the emulsified mixture. Particle size proportionally decreased with increasing the rotating speed (1.8 μm per 100 rpm increase in the range of 300–1,200 rpm) and surfactant concentration (3.1 μm per 0.1% increase in the range of 0.1–0.5%). The collagen microspheres showed a slight positive charge of 8.86 and 3.15 mV in phosphate-buffered saline and culture medium, respectively. Release study showed the sustained release of rhVEGF for 4 weeks. Released rhVEGF was able to induce capillary formation of human umbilical vein endothelial cells, indicating the maintenance of rhVEGF bioactivity after release. In conclusion, the results suggest that the collagen microspheres have potential for sustained release of rhVEGF.  相似文献   
100.
Seventeen limonoids (tetranortriterpenoids 1-17) were isolated from the n-hexane extract of Azadirachta indica (neem) seeds. The previously unidentified compound 16 was established by spectroscopy to be 17-defurano-17-oxosalannin. The effects of six compounds, 6 and 11-15, on melanogenesis in B16 melanoma cells was evaluated; 2 compounds, salannin (13) and 3-deacetylsalannin (15), exhibited marked inhibitory effects (70-74% reduction of melanin content at 25 μg/mL) with only minor cytotoxicity (79-85% of cell viability). Eleven compounds, 2, 3, 5, 6, and 9-15, were evaluated for inhibitory activity against 12-O-tetradecanoylphorbol-13-acetate (TPA)-induced inflammation (1.7 nmol/ear) in mice; all exhibited marked anti-inflammatory activity (ID(50) values 0.22-0.57 μmol/ear). In addition, compounds 6 and 11-16 exerted moderate inhibition (IC(50) values of 410-471 mol ratio/32 pmol TPA) of TPA-induced Epstein-Barr virus early antigen (EBV-EA) activation in Raji cells. The triacylglycerol fraction of the n-hexane extract contained oleic acid (50.2%) as the most predominant fatty acid constituent.  相似文献   
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