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91.
We discuss the elementary vortex pinning in type-II superconductors in connection with the Anderson's theorem for nonmagnetic impurities. We address the following two issues. One is an enhancement of the vortex pinning energy in the unconventional superconductors. This enhancement comes from the pair-breaking effect of a nonmagnetic defect as the pinning center far away from the vortex core (i.e., the pair-breaking effect due to the non-applicability of the Anderson's theorem in the unconventional superconductors). The other is an effect of the chirality on the vortex pinning energy in a chiral p-wave superconductor. The vortex pinning energy depends on the chirality. This is related to the cancellation of the angular momentum between the vorticity and chirality in a chiral p-wave vortex core, resulting in local applicability of the Anderson's theorem (or local recovery of the Anderson's theorem) inside the vortex core.  相似文献   
92.
Ando  H. Oohashi  H. Iwamura  H. Kanbe  H. 《Electronics letters》1989,25(18):1212-1214
Experiments demonstrate that the optical nonlinear response in a GaAs/AlGaAs nipi-MQW structure can be improved by introducing ohmic contacts, which electrically connect n- and p-layers. The response time is reduced by more than two orders of magnitude because of the enhanced recombination rate of photoexcited carriers, whereas the figure of merit for absorptive nonlinearity sigma /sub eh/ is kept constant and is an order of magnitude larger than that in a conventional GaAs/AlGaAs MQW structure.<>  相似文献   
93.
94.
The authors report a case of entrapment neuropathy of the deep peroneal nerve associated with the extensor hallucis brevis. This entrapment neuropathy was found distal to the inferior retinaculum that causes the anterior tarsal tunnel syndrome. Surgical decompression of the deep peroneal nerve that was entrapped by the extensor hallucis brevis relieved the symptoms. This condition, like the anterior tarsal tunnel syndrome, deserves attention.  相似文献   
95.
To determine the diagnostic implications of measuring the serum thyroglobulin level in patients with a solitary follicular thyroid tumor, a retrospective study was conducted on 122 consecutive patients with a solitary follicular thyroid nodule who underwent thyroidectomy. Data for eight variables were collected: the serum thyroglobulin (Tg) level (microgram/l), age, maximum diameter of the nodule, gender, histopathologic type, presence or absence of metastases, macroscopic characteristics of the cut surface of the resected tumor, and smoking habit. Multiple regression analyses were used to investigate the relationships between the serum Tg level and the seven other variables. The diagnostic value of serum Tg was examined by means of receiver operating characteristic (ROC) curves. There were significant correlations between the serum Tg level and the maximum diameter of the nodule, the macroscopic characteristics, and the smoking habit. The sensitivity and specificity of the serum Tg level with a cut-off value of 1,000 micrograms/l were 57% and 86%, respectively. The likelihood ratio favouring follicular carcinoma associated with the serum Tg > 1,000 micrograms/l was 4.41. Measuring the level of serum Tg may be useful in discriminating follicular carcinoma from follicular adenoma, but since there may be some biases in this retrospective study, the results are less definitive. Further research activities are mandatory to obtain valid evidence.  相似文献   
96.
To determine the major antigenic component of Candida albicans against immunoglobulin E (IgE) antibodies in the sera of patients with allergies who were positive for IgE antibodies to C. albicans crude antigen in a CAP system, phosphomannoproteins (CAMP/A or CAMP/B for serotype A or B strain, respectively) and their acid-stable portions (CAMP-S/A or CAMP-S/B) were isolated from beta-mercaptoethanol (2-ME) extracts of C. albicans cells of serotypes A and B, and IgE antibodies against these components were compared with those against protein complex and enolase (CAE) fractions isolated from C. albicans cells. The dot blot test, which was used to detect IgE antibodies to the C. albicans antigens, showed that IgE antibodies to the 2-ME extract and phosphomannoprotein fractions were present in the sera of 98.0% (2-ME extract), 96.8% (CAMP/A), 93.2% (CAMP-S/A), 97.2% (CAMP/B), and 81.5% (CAMP-S/B) of the patients, whereas IgE antibodies to the protein complex and CAE fractions were found in the sera of 73.6 and 48.8% of the patients, respectively. The extent of IgE binding to the 2-ME extract and phosphomannoproteins was well correlated with the fluorescence intensities estimated with the CAP system. Furthermore, the results obtained from the inhibition experiment with the CAP system indicated that the binding of IgE antibodies to Candida antigens is strongly inhibited by the phosphomannoprotein fraction and is an indication that the serum of the patients contained IgE antibodies specific to the cell wall phosphomannoproteins of C. albicans. Finally, an initial chemical analysis indicated that the epitopes for IgE antibodies on the phosphomannoproteins is a carbohydrate portion, since the ability of CAMP/A to inhibit the binding of IgE antibodies to the homologous CAMP/A was destroyed after oxidation by sodium periodate but not after digestion with proteinase K.  相似文献   
97.
Absorptive nonlinearity in a GaAs/AlGaAs n-i-p-i-MQW (multiple quantum well) structure consisting of alternating n-AlGaAs, i-GaAs/AlGaAs MQW, and p-AlGaAs layers is investigated. A change in the absorption coefficient of more than 4000/cm is obtained in the i-MQW layer with an extremely low excitation intensity on the order of 1 mW/cm 2. The figure of merit for absorptive nonlinearity, σ ch, defined as the change in the absorption coefficient induced by excitation of an electron-hole pair per unit volume, is experimentally evaluated to be 7×10-13 cm2, which is an order of magnitude larger than that for saturation of excitonic absorption in a conventional MQW structure. This experimental value agrees well with the theoretical estimation, which is calculated assuming an optical nonlinear process  相似文献   
98.
Mycobacterium sp. G3 was reported as a dibenzothiophene (DBT)-degrading microorganism and the first strain to have the ability to degrade high-molecular-weight alkyl DBTs, such as 4,6-dibutyl DBT and 4,6-dipentyl DBT, by the C-S bond cleavage pathway. Three genes (mdsA, mdsB, and mdsC) for desulfurization, which form a cluster, were cloned from Mycobacterium sp. G3. The expression of each gene in Escherichia coli JM109 showed that MdsC oxidized DBT to DBT sulfone, MdsA transformed DBT sulfone into 2-(2'-hydroxyphenyl)benzene sulfinate (HPBS), and MdsB desulfinated HPBS into 2-hydroxybiphenyl (HBP), indicating that the gene products of mdsABC are functional in the recombinant. MdsC oxidized 4,6-dimethyl DBT, 4,6-diethyl DBT, 4,6-dipropyl DBT and 4,6-dibutyl DBT to each sulfone form, suggesting that MdsC covers a broad specificity for alkyl DBTs.  相似文献   
99.
Abstract— A new driving method for an advanced‐CEL‐structure panel has been developed. Picture qualities have been upgraded. Discharge time lags are drastically shortened by priming electron emission from magnesium oxide (MgO) single‐crystal powder, refered to as a crystal emissive layer (CEL). The advanced‐CEL‐structure panel has CEL material on the surface of not only the surface‐discharge‐electrode side but also on the address‐electrode side. This panel structure enables a stable opposed discharge when the address electrode functions as a cathode. By utilizing the opposed discharges in the reset and LSB‐SF sustain periods, the dark‐room contrast ratio has been drastically increased to over 20,000:1, which is higher than five times that of the conventional method, and the luminance of the least‐significant‐bit sub‐field (LSB‐SF) is as low as 0.1 cd/m2, which is one‐fourth that of the conventional method. The high‐picture‐quality PDP TVs refered to as “KURO” that employs these technologies have been introduced into the marketplace.  相似文献   
100.
The wavelength of Raman-scattered light depends on the molecular composition of the substance. This is the first attempt to acquire Raman spectra of a mouse eyeball removed from a living mouse, in which the eyeball was preserved using the "in vivo cryotechnique" followed by freeze-drying. Eyeballs were cryofixed using a rapid freezing cryotechnique, and then sliced in the cryostat machine. The slices were sandwiched between glass slides, freeze-dried, and analyzed with confocal Raman microscopy. Important areas including various eyeball tissue layers were selected using bright-field microscopy, and then the Raman spectra were obtained at 240 locations. Four typical patterns of Raman spectra were electronically mapped on the specimen images obtained by the bright-field microscopy. Tissue organization was confirmed by embedding the same eyeball slice used for Raman spectra into epoxy resin and the thick sections were prepared with the inverted capsule method. Each Raman spectral pattern represents a different histological layer in the eyeball which was mapped by comparing the images of toluidine blue staining and Raman mapping with different colors. In the choroid and pigment cell layer, the Raman spectrum had two peaks, corresponding to melanin. Some of the peaks of the Raman spectra obtained from the blood vessels in sclera and the photoreceptor layer were similar to those obtained from the purified hemoglobin and rhodopsin proteins, respectively. Our experimental protocol can distinguish different tissue components with Raman microscopy; therefore, this method can be very useful for examining the distribution of a biological structures and/or chemical components in rapidly frozen freeze-dried tissue.  相似文献   
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