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61.
Spondyloepiphyseal dysplasia congenita (SEDC) can be accompanied by hypoplasia of the odontoid and/or lax ligaments which may lead to spinal cord compression. Since an early diagnosis of myelopathy is essential for rational treatment, identification of the high-risk factors is imperative. Sixteen patients were retrospectively reviewed, 10 male and 6 female, and their average age at the time of examination was 18 (range 3-37) years. Myelopathy was seen in 6 individuals. Five were associated with atlantoaxial subluxation, and the critical value of space available for the spinal cord at the level of the atlas was 10 mm or less. Their height was less than -7SD of average Japanese of the same age, and all were associated with severe coxa vara. Although SEDC itself is a risk factor, marked short stature of less than -7SD and severe coxa vara are particularly high-risk factors for cord compression at the level of the atlas.  相似文献   
62.
Backscattering yields in the <001> axial channeling mode using D+ ions have been measured for YBa2Cu3O7–y single crystals with Tc=59K. 68K and 91K at temperatures between 40K and 295K. In 60 K-class YBa2Cu3O7–y with significant anomalies associated with the spin gap, it is found that the channeling anomalies are observed at 130–140 K(Tpa) in addition to anomalies at Tc. The channeling anomalies at Tc follow to the shift of Tc, suggesting the phonon anomalies induced by the superconducting-gap opening. On the other hand, Tpa is found to be almost unchanged for varying Tc, although Tpa appears near the temperature where the spin gap is opened. This leads a question whether the channeling anomalies at Tpa is directly related to the phonon anomalies induced by the spin-gap opening. The existence of lattice instability is suggested as one of possible explanations for the anomalies at Tpa.  相似文献   
63.
A hardware method for functional unit assignment is presented, based on the principle that a functional unit's power consumption is approximated by the switching activity of its inputs. Since computing the Hamming distance of the inputs in hardware is expensive, only a portion of the inputs are examined. Integers often have many identical top bits, due to sign extension, and floating points often have many zeros in the least significant digits, due to the casting of integer values into floating point, and other reasons. The accuracy of these approximations is studied and the results are used to develop a simple, but effective, hardware scheme.  相似文献   
64.
The current study was undertaken to investigate the effect of swimming training on the antioxidant enzyme system in kidney of young and old mice. Both young and old mice, aged 2 and 26 months old, respectively, were divided into the sedentary and swimming-trained groups. The trained mice underwent a 6-week swimming program (1 h/day, 5 days/week) in water at 35-36 degrees C. Cu,Zn-superoxide dismutase (Cu,Zn-SOD) activity was significantly decreased with aging but was not influenced by swimming training, such changes being similar to those noted for catalase activity rather than for glutathione peroxidase activity. After swimming training Mn-SOD activity increased significantly only in old mice but was unaffected by aging. Although neither aging nor swimming training had overt effect on the expression of Cu,Zn-SOD mRNA, the immunoreactive Cu,Zn-SOD content in young mice decreased significantly after the training. Meanwhile, Mn-SOD mRNA expression in old mice was reduced by half after swimming training, accompanied by a significant decrease in its immunoreactive content; unexpectedly, however, Mn-SOD content in young mice did not parallel its mRNA expression. These findings suggest that the antioxidant enzyme system in mouse kidney trends to be down-regulated with aging, and that swimming training fails to attenuate such reduced levels of the antioxidant enzymes.  相似文献   
65.
66.
Cotton fibers mercerized under the relaxed state were hydrolyzed with crude cellulase. The mercerization treatment examined included ammonia treatment, sodium hydroxide treatment, and two combined treatments using ammonia and sodium hydroxide. Crystalline regions of the mercerized fibers were hydrolyzed in the first step of hydrolysis. In this step, ammonia treatment decreased the crystallite size to a great extent due to the hydrolysis of the cellulose III crystalline phase. Cellulase treatment rendered the crystallite surface highly accessible to water molecules. The crystalline phase was closely related to water sorption of cellulase‐treated fibers. The sequence of treatment had an influence on the fiber structure in the case of the combined mercerization treatment with ammonia and sodium hydroxide. © 2000 John Wiley & Sons, Inc. J Appl Polym Sci 78: 364–370, 2000  相似文献   
67.
The first step in the hydrolysis of cuprammonium rayon with endocellulases was examined and the results were compared with those of hydrolysis with a cellulase complex. Mechanical agitation during endocellulase treatment was effective for the separation of the oligomers from the substrate. The endocellulases removed the intermediately ordered regions in the disordered matrix. The crystalline regions were negligibly affected by the endocellulases, while the cellulase complex considerably deaggregated the surface of the crystallite. The endocellulases enhanced the brittleness of the fabric more than did the cellulase complex. It was assumed that the hydrolysis with the endocellulases proceeded without molecular deaggregation of the fiber. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 79: 2543–2547, 2001  相似文献   
68.
Reactive dye dyeing was performed on cellulose fibers in combination with cellulase treatment. First, polynosic and cupra fibers were selected to discuss the saturation dye uptake of the previously cellulase-treated fibers. Cupra fiber exhibited a similar saturation dyeuptake dependence on weight loss, irrespective of dye species and the substantivity of the dyes. In the polynosic fiber, the saturation dye-uptake dependence on weight loss exhibited a minimum using a lower substantive dye and a maximum using a higher substantive dye. Comparative discussions of the saturation dye uptake based on X-ray and infrared measurements led to the assumption that a region dyeable with the higher substantive dye is created by the cellulase treatment of the polynosic fiber. This region is assumed to have some degree of order as shown by infrared spectroscopy. Next, cotton fiber, which is important from a practical viewpoint, is dyed and then hydrolyzed. It was found that the hydrolysis of cotton fiber dyed with a reactive monofunctional dye was retarded almost in the same manner as that dyed with Congo Red. The hydrolysis of cotton fiber dyed with dyes of higher substantivity and more bifunctional property was probably retarded to a greater extent compared to dyes of lower substantivity and less bifunctional property. © 1996 John Wiley & Sons, Inc.  相似文献   
69.
An 8 Mb embedded DRAM has been developed. The salient feature of this embedded DRAM is page fault tolerance. Accessing across different pages can be performed using a minimum column cycle. This feature is achieved by placing a data latch and a transfer gate between the bit line sense amplifier and the column select gate. This DRAM can be reconfigured as separated 2 Mb units when it is embedded as a macro cell of an ASIC library  相似文献   
70.
The topography and elasticity of living and fixed astrocytes cultured from the rat cerebra were studied quantitatively by atomic force microscopy (AFM). Ridge-like structures reflecting F-actin beneath the cell membrane were prominent in the contact-mode images of living astrocytes. Many of these ridges became unclear after fixation (2% glutaraldehyde). In addition, the ridge-like structures were invisible in the topography of living cells observed at zero-loading force in the force mapping mode, which is considered to show the real cell surface not pressed down by an AFM tip. The topography of fixed cells observed both in the contact mode and at zero-loading force in the force mapping mode was similar to that of living cells observed at zero-loading force in the force mapping mode, although some deformed areas were detected in the fixed cells. The elasticity map images of living astrocytes showed that the cell membrane above the nucleus was softer (2-3 kPa) than the surroundings, and that the cell membrane above F-actin was stiffer (10-20 kPa) than the surroundings. In the elasticity map images of fixed astrocytes, on the other hand, the elasticity of the cells was found to be relatively uniform (200-700 kPa) irrespective of the inner structures of cells. These results show that images observed by AFM should be carefully examined in consideration of the force introduced to specimens and the elasticity of specimens to find out the real surface topography.  相似文献   
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