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1.
To develop the molecular differentiation analysis of dermatophytes, we carried out RAPD and Southern hybridization analyses using genomic DNAs of six Arthroderma species, including A. fulvum, A. grubyi, A. gypseum, A. incurvatum, A. otae and A. racemosum. The RAPD analysis gave different band patterns specific to each of the six Arthroderma fungi. However, minor differences in the banding patterns were observed between the strains of plus (+) and minus (-) mating types of A. gypseum, A. fulvum and A. incurvatum. Southern blot analysis using a probe (1S) obtained from A. grubyi DNA gave specific bands only in the DNA samples of A. grubyi and A. incurvatum. On the other hand, Southern blot analysis using a probe (C3) obtained from A. otae DNA gave specific bands in all six Arthroderma species examined, and the size of the bands were specific to each species. These findings indicate that RAPD and Southern hybridization analyses are useful in the differentiation of these Arthroderma species.  相似文献   
2.
After the liberalization of the Japanese telecommunications market in 1985, the market went through a first phase of competition, which focused on domestic telephony services, in both the long distance (domestic and international) and mobile segments. However, the growth of the Internet and the full digitalization of NTT's telecommunications network are ushering in a digital era and a second phase of competition. This article describes the current Japanese telecommunications market and the direction it is taking by referring to key statistical indicators  相似文献   
3.
Hydroliquefaction of low-sulfur Australian coals (Wandoan and Yallourn) was studied using iron carbonyl complexes as catalyst. The addition of Fe(CO)5 (2.8 wt% Fe of coal) increased coal conversion from 48.6 to 85.2% for Wandoan coal, and from 36.7 to 69.7% for Yallourn coal in 1-methylnaphthalene at 425°C under an initial hydrogen pressure of 50 kg cm?2. When molecular sulfur was added to iron carbonyls (Fe(CO)5, Fe2(CO)9 and Fe3(CO)12), higher coal converions ( > 92%) and higher oil yields (>46%) were obtained, along with an increase in the amount of hydrogen transferred to coal from the gas phase (0.2 to 2.8%, d.a.f. coal basis). In the liquefaction studies using a hydrogen donor solvent, tetralin, Fe(CO)5S catalyst increased the amount of hydrogen absorbed from the gaseous phase and decreased the amount of naphthalene dehydrogenated from tetralin. The direct hydrogen transfer reaction from molecular hydrogen to coal fragment radicals seems to be a major reaction pathway. Organic sulfur compounds, dimethyldisulfide and benzothiophene, and inorganic FeS2 and NiS were found to be good sulfur sources to Fe(CO)5. From X-ray diffraction analyses of liquefaction residues, it is concluded that Fe(CO)5 was converted into pyrrhotite (Fe1?xS) when sulfur was present, but into Fe3O4 in the absence of sulfur.  相似文献   
4.
The objective of this work is to discuss the concept of back‐to‐back interconnection systems with energy storage, especially with a Superconducting Magnetic Energy Storage (SMES) incorporated into a back‐to‐back DC link. In this case, each converter of the back‐to‐back system is used as a power conditioning system for the SMES coils. Since the AC–DC converter can be designed independently of the frequency of the power system, a two‐way switch is connected to the AC side of each converter. This two‐way switch can select the interconnected power systems. By using the two‐way switches, this system can provide the stored energy in the SMES system to each interconnected power system through two AC–DC converters. For instance, lower‐cost power of each power network can be stored through two converters during the off‐peak hours and made available for dispatch to each power network during periods of demand peak. Then this system increases the reliability of electric power networks and enables the economical operations depending on the power demand. This paper describes the unique operations of the back‐to‐back interconnection with SMES and discuses the optimal SMES configuration for a 300‐MW‐class back‐to‐back interconnection. © 2008 Wiley Periodicals, Inc. Electr Eng Jpn, 164(2): 37–43, 2008; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20482  相似文献   
5.
Ligand binding to neurotransmitter and hormone receptors which couple to the Gq subclass of GTP-binding protein leads to the activation of phospholipase Cbeta (PLCbeta) which hydrolyses phosphatidyl-inositol 4,5-bisphosphate, yielding a pair of second messengers, diacylglycerol and inositol 1,4,5-trisphosphate (IP3). The expression of PLCbeta1-4 mRNAs was comparatively examined by in situ hybridization in the mouse brain. In adults, PLCbeta1 mRNA was expressed predominantly in the telencephalon, including the cerebral cortex, hippocampus, amygdala, lateral septum and olfactory bulb, with little expression in most thalamic nuclei. PLCbeta2 mRNA was distributed in the white matter, suggesting its expression in non-neuronal cells, most likely oligodendrocytes. PLCbeta3 mRNA was specifically expressed in cerebellar Purkinje cells. The highest levels of PLCbeta4 mRNA were detected in Purkinje cells. High levels of PLCbeta4 mRNA were also found in the thalamus and medial septum, whereas weak signals were detected in most telencephalic regions, thus showing an expression pattern almost reciprocal to that of PLCbeta1 mRNA. During development, such characteristic regional expression of PLCbeta1 and PLCbeta4 were observed starting in late foetal stages, while specific expression of PLCbeta2 and PLCbeta3 appeared in early postnatal stages. We conclude that despite the existence of four PLCbeta isoforms, only one or two of them is expressed in individual neurons and glial cells. The distinct expression of PLCbetas provides a molecular basis for analysing the nature of the specific signal transduction pathway leading to the production of diacylglycerol and IP3 in distinct cell types and in different regions of the brain.  相似文献   
6.
Porous ZrO2 ceramics were fabricated by compacting a fine ZrO2 powder, followed by pressureless sintering. Two unidirectional pressures of 30 and 75 MPa were used to prepare the green compacts. The strength and the fracture toughness of porous ZrO2 specimens sintered from the compacts prepared by 75 MPa were substantially higher than those by 30 MPa, especially for the specimens with low porosity. However, the corresponding Young's moduli were identical. This caused the strain to failure of these porous bodies to increase significantly with increasing compaction pressure. Microstructural analyses showed that a number of voids and small flaws existed in the green compacts prepared by the lower pressure, due to the agglomeration of fine ZrO2 grains. It was revealed that the ZrO2 agglomeration resulted in a localized nonuniform shrinkage and degraded the mechanical properties of porous ZrO2 ceramics.  相似文献   
7.
Abstract— The display used in current cell phones has an air gap between the cover glass and the liquid‐crystal‐display (LCD) module to prevent the LCD glass from being damaged. Reflections at the boundaries of the air gap cause a reduction in the LCD luminance and contrast. To address this problem, a newly proposed LCD structure has been investigated. The “Super View Resin (SVR),” a transparent elastic resin which improves the shock resistance and visibility of the LCD, has been developed. Filling the air gap between the cover glass and LCD module with a refractive‐index‐matching resin solves the light‐reflection problem inherent in the use of a reinforced cover‐glass lens. Moreover, the elastic filler works as a damper, reducing any external shock, which prevents not only the cover glass and LCD module from being damaged, but also the glass from being shattered when it is broken.  相似文献   
8.

Epilepsy is a neurological disorder that may affect the autonomic nervous system (ANS) from 15 to 20 min before seizure onset, and disturbances of ANS affect R–R intervals (RRI) on an electrocardiogram (ECG). This study aims to develop a machine learning algorithm for predicting focal epileptic seizures by monitoring R–R interval (RRI) data in real time. The developed algorithm adopts a self-attentive autoencoder (SA-AE), which is a neural network for time-series data. The results of applying the developed seizure prediction algorithm to clinical data demonstrated that it functioned well in most patients; however, false positives (FPs) occurred in specific participants. In a future work, we will investigate the causes of FPs and optimize the developing seizure prediction algorithm to further improve performance using newly added clinical data.

  相似文献   
9.
Softsensors or virtual sensors are key technologies in industry because important variables such as product quality are not always measured on-line. In the present work, two-stage subspace identification (SSID) is proposed to develop highly accurate softsensors that can take into account the influence of unmeasured disturbances on estimated key variables explicitly. The proposed two-stage SSID method can estimate unmeasured disturbances without the assumptions that the conventional Kalman filtering technique must make. Therefore, it can outperform the Kalman filtering technique when innovations are not Gaussian white noises or the characteristics of disturbances do not stay constant with time. The superiority of the proposed method over the conventional methods is demonstrated through numerical examples and application to an industrial ethylene fractionator.  相似文献   
10.
In this study, the correlation between the stress–strain behavior of a carbon fiber-reinforced plastic (CFRP) and the temperature at which the heat-affected zone (HAZ) is generated is investigated. First, CFRP ([?45/45]2s laminate) specimens were heated at several temperatures to induce thermal damage, i.e. a HAZ. Subsequently, tensile tests were conducted on the specimens with thermal damage. Then, microscopy and X-ray measurements were carried out to discuss the stress–strain responses from a microscopic viewpoint. The results of strain measurement during thermal treatment indicated that the strain increases with increasing temperature. The tensile tests showed that the CFRP specimens subjected to thermal damage during heating at a high temperature fractured in the ductile mode, whereas the fracture mode of the CFRP specimens with low-temperature thermal damage was discontinuous. Microstructure observation using X-ray tomography showed that the debonding between the carbon fibers and the resin matrix induced by heating to above the glass transition temperature was responsible for the continuous fracture mode.  相似文献   
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