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131.
Between 1974 and 1995 we encountered 19 cases of bronchial stricture or obliteration caused by endobronchial tuberculous lesions. In 11 the involvements were located at the right bronchus (including involvements of segmental and middle lobe bronchi) and in 8 at the left bronchus. On bronchoscopic biopsy of the stenosed bronchus, 7 patients showed histopathologic findings of tuberculous bronchitis, but 12 patients showed nonspecific inflammatory granular tissue. Five patients were kept under conservative observation because of mild subjective symptoms or refusal to undergo operation. Two patients underwent stent procedures but had poor outcomes. Twelve patients underwent operation. As the bronchial lesions in four of them were confined to the lobar or segmental bronchus, lobectomy was performed. One patient with a history of infantile tuberculosis had developed complete obliteration of the left main bronchus and cystic bronchiectasis in the entire lung parenchyma; pneumonectomy was essential. Seven patients who had strictures involving the main bronchus underwent bronchoplastic surgery with right (n = 4) or left (n = 3) upper sleeve lobectomy. None of the patients treated surgically showed any postoperative complication or recurrence of the tuberculosis. These surgical results for endobronchial tuberculosis indicate the need for early detection and operation. Bronchoscopy and computed tomography are the methods of choice for accurate diagnosis of bronchial involvement and assessment of the surgical indications. It is emphasized that bronchoplastic surgery is the best treatment for bronchial stricture involving bilateral main bronchi.  相似文献   
132.
The intrinsic contact angle between liquid metal and a solid substrate is important for interpreting the contact interaction between them. However, the apparent contact angle revealed in a wetting test does not always coincide with the intrinsic angle. In this study, the intrinsic contact angle of liquid silver on monocrystalline and polycrytalline graphite substrates was investigated by means of a sessile drop method under a 10%H2−Ar atmosphere at 1273 K. The intrinsic contact angles were estimated to be 124° for the monocrystalline (C surface) and 127° for the polycrystalline.  相似文献   
133.
A novel method for preparing and characterizing super-hydrophobic and oleophobic surface is presented. Aluminum (Al) substrate was roughened by sandblasting and electrolytic etching to obtain micro- and nano-sized complex morphologies. Then, its substrate was covered by a chemically adsorbed monolayer (CAM) containing a fluorocarbon group. The surface of Al substrate roughened and covered with CAM was observed by scanning electron microscope and atomic force microscope. The roughnesses of the surface were ca. 100 μm and ca. 30–60 nm, respectively. The surface of the wettability was characterized by contact angle measurements and its surface indicated super-hydrophobicity and oleophobicity: the water contact angle (WCA) and oil contact angle (OCA) of hexadecane was 158.9° and 139.6°, respectively. The wettability was also characterized by solid surface energy. The solid surface energy of each solvent was obtained from the equation by Neumann et al. These values were extremely low, ranging from 0.31 to 1.29 mN/m. The total solid surface energy was obtained from the equation by Kaelble et al. The value was 0.3 mN/m. Their values indicated that the hydrophobicity and oleophobicity of our sample reached the highest level possible. In addition, our research demonstrates that it is easy to compare many different surfaces with super-hydrophobicity and oleophobicity using the solid surface energy.  相似文献   
134.
135.
To simulate the effects of burnable poison doping in nuclear fuel UO2,Er2O3(or Gd2O3)-doped CeO2 pellets were prepared. Changes in lattice constant and atomic disordering for CeO2 due to the Er2O3 and Gd2O3 doping were measured by means of XRD and XAFS. By the Er2O3 doping,the lattice constant decreased,and a disordering of lattice structure was induced in the samples. The doping with Er2O3 also induced the disordering of atomic arrangement around Er atoms,which was observed through the change in XAFS spectra. In contrast,the effect of Gd2O3 doping was smaller than that of Er2O3 doping. The result was discussed in terms of ionic size of dopants in CeO2 crystal.  相似文献   
136.
This article describes a study of how a cable TV channel, run by a small rural town in Japan, influences the awareness and behaviour of its residents. The study is based on a postal survey. Results indicate that the TV programmes increase residents interests in the community, communication among residents, and resident participation in public activities. They also show that such effects on the community are influenced by the usefulness of the programmes, viewing frequency, amount of community participation, and certain personal attributes of residents, such as gender, age and household type.Received: 2 May 2001, Accepted: 26 February 2003, JEL Classification: L82, R29, R58Kazufumi Ueno: I would like to thank 21st Century Research Organization for Human Care, formally the 21st Century Hyogo Project Association, for permission to use the survey data for this study.  相似文献   
137.
An optimal microscope is useful for observing various kinds of samples. However, precise observation of an extended region in depth is difficult, because of the narrow range of depth of focus. To overcome this problem, this paper proposes a method of obtaining a pan-focused stereoscopic image. By using image processing, in-focus areas are extracted from multiple images focused on slightly different depths, and a stereoscopic image is composed with these in-focus areas. The proposed method is applied to the observation of three-dimensional distributions of soil particles, a common problem in the field of civil engineering, and the usefulness of the proposed method is demonstrated.  相似文献   
138.
Displaying objects with high accuracy is necessary for CAGD (computer-aided geometric design) and for the synthesis of photo-realistic images. Traditionally, polygonal approximation methods have been employed to display free-form surfaces. They bring on low accuracy of display not only in shape, but also in intensity of objects. In this paper, a scanline algorithm to directly display parametric surface patches, expressed by trimmed Bézier surfaces, without polygonal approximation is proposed. In the method proposed here, curved surfaces are subdivided into subpatches with curved edges intersecting with a scanline, and the intersections of every subpatch and the scanline are calculated. This method is extremely robust for calculating the intersections, which can be obtained with only a few iterations; the Bézier clipping method is used for the iteration. Anti-aliased images with shadows and texture mapping are given to show the effectiveness of the method proposed.  相似文献   
139.
A case of bilateral congenital aplasia of the carpal scaphoid bone is presented. In contrast to previously reported cases of congenital hypoplasia of the scaphoid, this case was not associated with hypoplasia or absence of thenar and forearm muscles, absence of the sesamoid bones of the thumb, abnormalities of the skeleton of the thumb ray or hypoplasia of the forearm bones.  相似文献   
140.
Abstract

A correlation between ferroelectric properties of the PLZT capacitors and amount of H2 and H2O gasses desorbed from interlayer dielectrics were investigated quantitatively. H2 and H2O gasses desorbed from interlayer dioxides were analyzed using thermal desorption spectroscopy. Polarization charges and its aging characteristics of memory array capacitors with area of 2 μm squares did not depend on amount of desorbed H2 explicitly, but strongly on H2O desorption. It is considered that silanol and hydroxyalkyl groups worked as hydrogen donor with catalytic activities of Pt top electrodes. As a result, hydrogen atoms should work as a major degradation agent for the imprint phenomena of memory array capacitors. Precise control of hydroxyl groups contained in the interlayer dielectrics and passivation films resulted in very small retention degradation caused by imprint phenomena, and realized high reliability and high density FRAM technologies.  相似文献   
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