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151.
152.
We describe a 51 year-old man with calcified early gastric cancer. The calcification was not displayed by abdominal X-ray, CT, or conventional ultrasound. Only endoscopic ultrasonography displayed the distribution of calcification in vivo. Endoscopic ultrasonography revealed a slightly hypoechoic lesion with a high echoic line, without involvement of the fourth layer. Histopathologically, it was a IIc type early gastric cancer. The depth of cancer invasion was limited to the mucosa and a mucin pool was not observed. Psammomatous calcification was observed in the lumen of the carcinomatous glands. This seems to be the first case reported in which psammoma bodies were observed in early gastric cancer.  相似文献   
153.
This paper describes an evaluation of the proton irradiation effects on the thermal characteristics of a pyrolytic graphite sheet (PGS), which has characteristics of high thermal conductivity, light weight, and flexibility, in order to apply this material to an advanced spacecraft thermal control device, the reversible thermal panel (RTP). The results show slight changes in the in-plane thermal diffusivity and total hemispherical emittance of the PGS for 2.0 MeV proton irradiation. An RTP prototype model based on the PGS was designed and fabricated, and its thermal performance was evaluated. The effects of changes in thermal characteristics of the PGS on the thermal performance of the RTP were also discussed.Paper presented at the Seventh Asian Thermophysical Properties Conference, August 23–26, 2004, Hefei and Huangshan, Anhui, P. R. China.  相似文献   
154.
Measurements of the thermal conductivity of HFC-32, HFC-125, and HFC-134a were carried out for the first time in both solid and liquid phases at the saturation pressure at room temperature and in the temperature ranges from 120 to 263, from 140 to 213, and from 130 to 295 K, respectively. A transient hot-wire instrument using one bare platinum wire was employed for measurements, with an uncertainty of less than ±2%. The experimental results demonstrated that the thermal conductivity of HFC-32, HFC-125, and HFC-134a in the solid phase showed a positive temperature dependence. For HFC-32 and HFC-125, there were big jumps between the solid and the liquid thermal conductivity at the melting point. But for HFC-134a, the solid and liquid thermal conductivity at the melting point is almost-continuous.  相似文献   
155.
hCDC47 is a human member of the MCM family, which has been implicated to be concerned with the regulatory machinery causing DNA to replicate once per cell cycle. In a previous paper, we described hCDC47 expression as being localized in the proliferative component of normal tissues, and showed greater expression in squamous cell skin carcinomas than in seborrheic keratosis. In the present study, we compared its expression in another type of skin tumor and various non-neoplastic cutaneous proliferative diseases. Two patterns of distribution of hCDC47-positive cells were observed. Keratoacanthomas showed a peripheral pattern in which only the cells located the basal cell layers were positive. Psoriasis vulgaris also showed this peripheral type of location, with the cells in the suprabasal layers also occasionally expressing hCDC47. Verruca vulgaris demonstrated a diffuse pattern, with positive epithelial cells distributed throughout the layers. Basal cell carcinomas also showed a similar pattern. The keratoacanthomas showed the highest hCDC47 positive cell rate (43.1%), followed by verruca vulgaris (42.5%), psoriasis vulgaris (23.4%), and basal cell carcinoma (17.3%). Our results suggest participation of hCDC47 in these proliferative disorders involving keratinocytes.  相似文献   
156.
The first objective of this study is to determine the theoretical potential of solar irradiation in Indonesia by using artificial neural networks (ANNs) method. The second objective is to visualize the solar irradiation by province as solar map for the entire of Indonesia. The geographical and meteorological data of 25 locations that were obtained from NASA database are used for training the neural networks and the data from 5 locations were used for testing the estimated values. The testing data were not used in the training of the network in order to give an indication of the performance of the system at unknown locations. In this study, the multi layer perceptron ANNs model, with 9 inputs variables i.e. average temperature, average relative humidity, average sunshine duration, average wind speed, average precipitation, longitude, latitude, latitude, and month of the year were proposed to estimate the monthly solar irradiation as the output. Statistical error analysis in terms of mean absolute percentage error (MAPE) was conducted for testing data to evaluate the performance of ANN model. The best result of MAPE was found to be 3.4% when 9 neurons were set up in the hidden layer. As developing country and wide islands area, Indonesia has the limitation on the number of meteorological station to record the solar irradiation availability; this study shows the ANN method can be an alternative option to estimate solar irradiation data. Monthly solar mapping by province for the entire of Indonesia are developed in GIS environment by putting the location and solar irradiation value in polygon format. Solar irradiation map can provide useful information about the profile of solar energy resource as the input for the solar energy system implementation.  相似文献   
157.
OBJECTIVE: This study was performed to assess the usefulness of preoperative thin-section CT alone and in combination with physiologic measurements in emphysema patients being evaluated for lung volume reduction surgery. SUBJECTS AND METHODS: Six 1-mm collimation sections through the chest were obtained in 20 patients being evaluated for lung volume reduction surgery. Extent and severity of emphysema were assessed by visually scoring the images. CT scores ranged from 0 to 144. Inspiratory resistance was measured in 12 of 20 patients and was also used to discriminate between responders (change in forced expiratory volume in 1 sec, > or = 150 ml after surgery) and nonresponders (change in forced expiratory volume in 1 sec, < 150 ml after surgery). RESULTS: Four of 20 patients with mild emphysema as revealed by thin-section CT (scores of < 50) did not improve lung function after lung volume reduction surgery. Eight of the remaining 16 patients with moderate to severe emphysema as revealed by thin-section CT (scores of > 50) underwent inspiratory resistance measurement. Those seven patients whose inspiratory resistance measurement exceeded 8.5 cm H2O/l per second did not respond favorably to lung volume reduction surgery (change in forced expiratory volume in 1 sec, < 150 ml). The remaining five patients whose inspiratory resistance measurement was less than 8.5 cm H2O/l per second responded favorably to lung volume reduction surgery. Thus, only five of the 20 patients showed improvement in forced expiratory volume in 1 sec after surgery. CONCLUSION: Our data suggest that among patients with moderate to severe emphysema who are being examined for lung volume reduction surgery, the combination of radiologic and physiologic assessment is more accurate for predicting a favorable response to lung volume reduction surgery than radiologic assessment alone. However, in patients with chronic obstructive pulmonary disease by the American Thoracic Society criteria, mild emphysema as revealed on thin-section CT virtually precludes further workup because these patients are unlikely to respond favorably to lung volume reduction surgery.  相似文献   
158.
The thermal conductivity of four pure normal paraffin hydrocarbons (C11, C14, C15, C16) and binary and ternary mixtures of three n-paraffin hydrocarbons (C7, C11, C16) have been measured in the temperature range from about 20 to 90°C at atmospheric pressure. Measurements have been performed with the aid of a fully automated transient hot-wire instrument. The accuracy of the reported data is estimated to be ±1.0 to ±1.5%. A new simple and practical equation, which can calculate the thermal conductivity of pure n-paraffin hydrocarbons (4n 16) with the uncertainty of ±1%, has been correlated in terms of temperature and number of carbon atoms based on the present results including some other reliable data. Also, a mixing rule for the mixtures of n-paraffin hydrocarbons was proposed and was adequately confirmed by the present results within the experimental error.  相似文献   
159.
The principle of corresponding states has been applied to the thermal-conductivity data for molten alkali halides which have been obtained by recent forced Rayleigh scattering measurements. The theory, which was developed by Harada et al. for the transport properties of uni-univalent molten salts, is based on the fluctuation-dissipation theorem with the pair interaction between ions composed of core repulsive and Coulombic potentials. Four characteristic parameters specific to each salt have been used to reduce the thermal conductivity and temperature. It has been found that the thermal conductivity of molten alkali halides is adequately correlated by the corresponding-states correlation ( * 1/T *) within experimental accuracy. By employing the correlation, the thermal conductivity of molten alkali fluorides, which could not be measured by the forced Rayleigh scattering method, is predicted.Paper dedicated to Professor Joseph Kestin.  相似文献   
160.
To apply annular output beams emitted from an unstable resonator to a multiple-pass cell (MPC) for Raman conversion, we studied the mode-matching condition of non-Gaussian beams to a MPC using beam propagation analysis based on Laguerre-Gaussian functions. During transits of the MPC, the radial profile of an annular beam changes between annular and Airy patterns. Although such behavior indicates that it is impossible to achieve complete mode matching of an annular beam, we found a quasi-mode-matching condition under which the variation of beam size was minimized. The above theoretical analysis was verified experimentally using a CO(2) laser beam prepared for a para-hydrogen Raman laser.  相似文献   
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