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61.
The incidence of aplastic anemia appears to be relatively high in some parts of the world, including Pakistan. Since some of the etiological factors are shared by aplastic anemia and the preleukemic syndrome, there is a strong possibility that a proportion of cases of aplastic anemia may in fact be preleukemia. The study of chromosomes offers a relatively easy method of detecting cases of preleukemia, because some chromosomal abnormalities are frequently observed in this condition. Chromosomal studies were carried out in peripheral blood cell cultures of 31 patients with otherwise typical aplastic anemia. Chromosomal abnormalities were detected in 7 (22.5%) cases. The most common chromosomal abnormality detected was trisomy 8, seen in four cases. Other abnormalities detected were 22q-, t(14;22) and t(15;21), in one case each. These abnormalities have been found to be associated with AML, MDS, ALL, and NHL as well. We hypothesize that a proportion of cases of otherwise typical aplastic anemia may in fact be due to a leukemic process in evolution.  相似文献   
62.
The effect of different processing methods (soaking in water or solutions of sodium bicarbonate, citric acid, soaking plus cooking, and germination) on anti-nutritional factors (phytic acid, total polyphenols, tannins, and hydrocyanic acid) of red kidney bean was studied. The anti-nutritional factors were reduced significantly (P < 0.001) with processing techniques. Cyanide contents were most effectively (25%) reduced by cooking after soaking in sodium bicarbonate solution, followed by germination. The most drastic effect was noted on tannin contents. Cooking after soaking in either citric acid or sodium bicarbonate solutions almost eliminated it. However, simple soaking in water did not result in any reduction in tannin contents. Reduction in total polyphenols was 78.7% with cooking after soaking in sodium bicarbonate solution. Phytic acid contents were reduced only with germination treatment (42.6%), while the other treatments did not bring about any large reduction.  相似文献   
63.
In this work, an algorithm for the numerical solution of the generalized Hirota–Satsuma equations and Jaulent–Miodek equations based on meshless radial basis functions (RBFs) method using collocation points, called Kansa's method, is presented. Four model problems with six different initial conditions are considered for the computation. A fairly explicit scheme is used to approximate the solution. The comparison is made with the exact solutions of each problem of the generalized Hirota–Satsuma coupled Korteweg–de Vries equations. A system consisting highly nonlinear partial differential equations known as Jaulent–Miodek equations and generalized Hirota–Satsuma coupled modified-Korteweg–de Vries equations are considered for comparison with the work already published. The multiquadric RBF results are compared with homotopy perturbation method (HPM) and variational iteration method (VIM) to highlight the excellent performance of the method.  相似文献   
64.
Autonomous navigation of microaerial vehicles in environments that are simultaneously GPS‐denied and visually degraded, and especially in the dark, texture‐less and dust‐ or smoke‐filled settings, is rendered particularly hard. However, a potential solution arises if such aerial robots are equipped with long wave infrared thermal vision systems that are unaffected by darkness and can penetrate many types of obscurants. In response to this fact, this study proposes a keyframe‐based thermal–inertial odometry estimation framework tailored to the exact data and concepts of operation of thermal cameras. The front‐end component of the proposed solution utilizes full radiometric data to establish reliable correspondences between thermal images, as opposed to operating on rescaled data as previous efforts have presented. In parallel, taking advantage of a keyframe‐based optimization back‐end the proposed method is suitable for handling periods of data interruption which are commonly present in thermal cameras, while it also ensures the joint optimization of reprojection errors of 3D landmarks and inertial measurement errors. The developed framework was verified with respect to its resilience, performance, and ability to enable autonomous navigation in an extensive set of experimental studies including multiple field deployments in severely degraded, dark, and obscurants‐filled underground mines.  相似文献   
65.
A high lithium conductive MoS2/Celgard composite separator is reported as efficient polysulfides barrier in Li–S batteries. Significantly, thanks to the high density of lithium ions on MoS2 surface, this composite separator shows high lithium conductivity, fast lithium diffusion, and facile lithium transference. When used in Li–S batteries, the separator is proven to be highly efficient for depressing polysulfides shuttle, leading to high and long cycle stability. With 65% of sulfur loading, the device with MoS2/Celgard separator delivers an initial capacity of 808 mAh g?1 and a substantial capacity of 401 mAh g?1 after 600 cycles, corresponding to only 0.083% of capacity decay per cycle that is comparable to the best reported result so far. In addition, the Coulombic efficiency remains more than 99.5% during all 600 cycles, disclosing an efficient ionic sieve preventing polysulfides migration to the anode while having negligible influence on Li+ ions transfer across the separator. The strategy demonstrated in this work will open the door toward developing efficient separators with flexible 2D materials beyond graphene for energy‐storage devices.  相似文献   
66.
This paper describes a new method of safety assessment of highway stopping and passing sight distances. Topographic data were collected by flying a plane equipped with a light detection and ranging (LiDAR) system on a section of two-lane rural highway. The collected data were manipulated in a geographic information system (GIS) to obtain three-dimensional models of the various highway subsections. These models were visually analyzed to check for stopping and passing sight distances, thus narrowing the list of locations with potential safety issues. Subsequent line-of-sight analysis in a GIS indicated the presence of several obstructions, prompting a field visit for validation. Field inspection of the locations verified the presence of the obstructions detected during the analysis. Overall, this research indicated the viability of successful visualization of LiDAR data for highway sight distance evaluations and is indicative of LiDAR’s potential for highway safety-related applications. Comments on the resources needed to embrace this technology and future research improvements are part of the paper.  相似文献   
67.
68.
Phase relationships in the La1?xSrxCrO3 (0.25 ≤ x ≤ 0) system have been investigated. Substitution of Sr into LaCrO3 leads to a phase region with rhombohedral symmetry at room temperature which is oxygen-deficient under strongly reducing conditions. The orthorhombic structure of LaCrO3 and the rhombohedral structure of La0.75Sr0.25CrO3 have been refined by profile fitting of neutron powder diffraction data.  相似文献   
69.
Electron beam evaporated Sn-doped In2O3 films have been prepared from the starting material with composition of (1 − x) In2O3 − -x SnO2, where x = 0.0, 0.010, 0.025, 0.050, 0.090, and 0.120. X-ray photoelectron spectroscopy, Rutherford backscattering spectrometry, and X-ray diffraction analysis were carried out on the films. Luminous transmittance and electrical resistivity of the films, show weak dependence on x. The composition of the film ([Sn]/[In] atomic ratio) was found to differ from that of the starting material. In fact, the atomic ratio was higher in the film than in the starting material by a factor which increases with x (ranging from 1.0 to 2.6). There is a relatively broad resistivity minimum in the layer atomic ratio range Sn/In = 0.06 − -0.09. These results compare well with those reported in the literature for Sn-doped In2O3 films, prepared by pyrolitic (spray) method.  相似文献   
70.
This paper focuses on the microstructure and fracture surface morphology of neat and carbon nanofibers (CNF) modified asphalts and hot mix asphalt (HMA) mixtures using scanning electron microscopy (SEM). Asphalt binder was modified with 1.5 % of CNF by weight of binder. The modified asphalt was used to construct HMA mixtures at various CNF dosages, mixed with aggregate, using the Superpave Gyratory compactor. Small rectangular specimens extracted from the center of large HMA samples were tested under direct tension and the fracture surface was examined under SEM. The SEM analysis developed a fundamental understanding of the role that the CNF modification plays in the performance enhancement of asphalt and HMA mixtures. It was found that CNF not only possess good adhesion characteristics but also exhibits high connectivity and were evenly distribution throughout the binder. The fracture surface morphology also revealed that CNF exhibited crack bridging at micro/nano scale which may enhance the resistance to cracking due to repeated traffic loads.  相似文献   
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