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51.
The behavior of oxide film on pure iron passivated in a borate buffer solution and subsequently radiated by infrared light (IR) was investigated in comparing to that by just IR annealing without passivation, and was evaluated by film structure, etc. The effect of thermal annealing over 250 degrees C was observed with gamma-Fe2O3 grain growth and sharp increase in surface roughness, film thickness and oxygen content. An ellipsometric parameter of tan psi was sensitively reflected by annealing effect, and tan psi curve had a shoulder at 150 degrees C for 5 min and a peak of tan psi was shifted from 350 nm to 450 nm in wavelength. This shift was also caused by the formation of gamma-Fe2O3, because the peak was also observed in tan psi of the bulk Fe2O3 family. Passivation effects at 800 mV prior to IR annealing on thickness and oxygen content changed at 150 degrees C, and decreased tan psi at 350 nm and excessive film growth over 250 degrees C, and increased oxygen content under 100 degrees C and surface roughness at 50-250 degrees C. The terrace width with atomic scale flatness was slightly increase by passivation prior to IR annealing at 50-250 degrees C, and the maximum terrace width reached larger than 10 nm by passivation and IR annealing at 100 degrees C for 30 min.  相似文献   
52.
The global and systematic demonstration for the practical usage of a direct three-dimensional in vivo measurement system (PRIMOS) to evaluate wrinkles was investigated. Ten repetitive measurements of the corner of the eye of a subject showed that the coefficient of variation (CV)% value was 7.0% in a typical line-length roughness parameter R(a) (the arithmetic mean of roughness), and that the CV% value in a typical surface area roughness parameter S(a) was 2.4%. The relationships between the roughness values obtained from the corners of the eye and the age or wrinkle scores of Japanese women aged 10-70 years was examined. The values of several roughness parameters within the evaluation line length or surface area increased with age and showed a good correlation coefficient (r > 0.743). Similar relationships between the wrinkle scores and the values of roughness parameters were observed (r > 0.699). The roughness values were widely distributed even in the same wrinkle score because the measurement areas were limited and the values of skin roughness, including the microreliefs and/or small warts, were included in the calculation. However, changes in roughness values are considerable following treatment with potent active ingredients such as retinoic acid, so that this in vivo evaluation method is sufficient to objectively evaluate wrinkles. We conclude that the direct three-dimensional analysis of wrinkles in vivo should become a popular method to objectively evaluate wrinkles in clinical tests of wrinkle-smoothing ingredients or following cosmetic surgery to provide evidence of quantitative results.  相似文献   
53.
In this study, we attempted to classify the methylotrophic yeasts based on diversities of alcohol oxidase (AOD), i.e. zymogram patterns and partial amino acid sequences. According to zymogram patterns for AOD, members of the methylotrophic yeasts separate into two major lineages, one group involving strains having a single AOD and the other group, including Pichia methanolica, Candida pignaliae and C. sonorensis, showing nine AOD isozymes. Based on partial amino acid sequences of AOD, the methylotrophic yeasts could be divided into five groups, and this classification agrees mostly with grouping based on 26S domain D1/D2 rDNA nucleotide sequences, except for some strains. Moreover, the strains having AOD isozymes constitute one group with P. trehalophila, P. glucozyma and Pichia sp. strain BZ159, although these strains are divided into two types, based on amino acid sequences of second AODs. On the other hand, these AOD isozymes consist of two subunits; the first subunits are induced not only by methanol but also by glycerol and pectin, although the second subunits are mainly induced by methanol. These data indicate that AOD isozymes and second AOD genes distribute widely in several methylotrophic yeasts in the natural environment, and second AOD genes may have evolved as methylotrophic genes that can adapt to the environmental conditions of higher methanol concentrations.  相似文献   
54.
We present reverse bias current (dark current) characteristics of a two-dimensional monolithic pixel-type nuclear radiation detector array fabricated using metalorganic vapor-phase epitaxy (MOVPE)-grown thick CdTe epitaxial layers on Si substrate. The (14?×?8) pixel array was formed by cutting deep vertical trenches using a dicing saw, where each pixel possesses a p-CdTe/ n-CdTe/n +-Si heterojunction diode structure. The dark currents showed pixel-to-pixel variations when measured at higher applied biases exceeding 100?V. The dark current had a dependence on the pixel thickness, where pixels with lower CdTe thickness exhibited higher currents. Moreover, the temperature dependence of the dark current revealed that a deep level with activation energy of around 0.6?eV is responsible for the observed dark currents and their pixel-to-pixel variation. We discuss that the effective ratio of Te to Cd at the growth surface is a major factor that controls the thickness variation, and is also responsible for the formation of 0.6?eV deep levels.  相似文献   
55.
To enhance photocatalytic water splitting, various oxidizing sacrifice agents (OSA) have been added to the system in order to scavenge the coproduced O2, and, thus, to hinder the reverse reactions. In the aim of achieving carbon‐neutral photocatalytic water splitting, nonfood hydrocarbons of castor‐ and jojoba‐oils were evaluated as OSA. Moreover, various surfactants were tested as emulsifiers for W/O binary solution for promoting photocatalytic water splitting rate. Among the OSA used, the castor‐oil was found to be more suitable candidate compared to jojoba‐oil, which was attributed to its smaller carbon chain numbers of mainly 18. Without surfactants, around 20 vol %‐castor‐oil aqueous binary solution with TiO2/Pt(0.10 wt %) provided the highest water splitting rate of about 30 mL‐H2/(m2·h). Among tested surfactants, liquid‐detergent was the best due to its optical transparency. 40 vol %‐ or 60 vol %‐castor‐oil emulsion with a drop of liquid‐detergent resulted in a water splitting rate of 125 mL‐H2/(m2·h), which was four times greater that the aforementioned highest value. © 2010 American Institute of Chemical Engineers AIChE J, 2011  相似文献   
56.
Membrane proteins play important roles in biological functions, with accompanying allosteric structure changes. Understanding intramolecular dynamics helps elucidate catalytic mechanisms and develop new drugs. In contrast to the various technologies for structural analysis, methods for analyzing intramolecular dynamics are limited. Single-molecule measurements using optical microscopy have been widely used for kinetic analysis. Recently, improvements in detectors and image analysis technology have made it possible to use single-molecule determination methods using X-rays and electron beams, such as diffracted X-ray tracking (DXT), X-ray free electron laser (XFEL) imaging, and cryo-electron microscopy (cryo-EM). High-speed atomic force microscopy (HS-AFM) is a scanning probe microscope that can capture the structural dynamics of biomolecules in real time at the single-molecule level. Time-resolved techniques also facilitate an understanding of real-time intramolecular processes during chemical reactions. In this review, recent advances in membrane protein dynamics visualization techniques were presented.  相似文献   
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To determine the usefulness of transvaginal ultrasonographic cervical assessment for the prediction of preterm delivery in an apparently normal population, 729 pregnant women (between 15 and 34 weeks' gestation) were randomly enrolled in the study in ten tertiary perinatal centers in Japan. Cervical parameters, including cervical length, internal os dilatation, and funneling depth, were measured by transvaginal ultrasound. The predictive values of these measurements for preterm delivery were investigated in a prospective fashion. Among various cervical parameters, cervical length showed the best correlation with pregnancy outcome. Cervical length (mm) was gradually decreased as the gestational age progressed, the regression line being y = 41.21-0.22x. When the mean cervical length minus 1 standard deviation at each gestational age was chosen as a cut-off value, the group with a shortened cervix showed a significantly high preterm delivery rate exclusively in the primigravidae (odds ratio: 4.86, 95% CI: 1.85-12.72). Internal os dilatation, in contrast, was a useful predictor in multiparous women (odds ratio: 6.00, 95% CI: 1.65-21.71). It was concluded that tranvaginal ultrasonographic cervical assessment, especially the measurement of cervical length, was effective for the prediction of preterm delivery in the primigravidae.  相似文献   
60.
Case 1, a 9-year-old woman, was admitted to our hospital because of nausea, vomiting, and epigastralgia. Diagnosis of Bochdalek hernia was made by the unusual course of naso-gastric tube. At surgery through the left posterorateral thoracotomy, the herniation of the stomach, small intestine, and colon to the thoracic cavity through the dorsolateral defect of the diaphragm were revealed. Case 2, a 35-year-old man, was admitted to our hospital because of dyspnea. Similar diagnosis was made by the examination of upper G1 series and barium enema, which demonstrated the presence of multiple loops of the small intestine and colon in the left thoracic cavity. Their postoperative courses were uneventful. Most of Bochdalek hernia is observed in infancy, and adolescent or adult case is is rarely reported (approximately 10% of all cases). Since this often misdiagnosed as pleuritis or pulmonary tuberculosis, a cautious examination is necessary for the establishment of the correct diagnosis.  相似文献   
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