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131.
Pavlov  G. Liotta  A. Abbi  P. Ceri  S. 《IEEE network》1998,12(5):10-20
CMIS/P is the OSI systems management service and protocol used as the base technology for the telecommunications management network. It is a generic object oriented protocol that provides multiple object access capabilities to managed object clusters administered by agent applications. Its navigation and object selection capabilities rely on traversing containment relationships. This is restrictive because information models for emerging broadband technologies (SDH/SONET, ATM) exhibit various other relationships. We present extensions to the CMIS service that provide a richer access language and show how these extensions can be supported by corresponding extensions to the CMIP protocol. These extensions allow traversal of any object relationship and filtering out objects at any stage of the selection process. CMIS++ provides much greater expressive power than CMIS, while CMIP++ supports the remote evaluation of the corresponding expressions, minimizing the management traffic required for complex management information retrieval. These extensions follow an incremental approach, starting from a version compatible with the current standard and gradually adding sophisticated features. The applicability and importance of the proposed concepts is demonstrated through an example from SDH management, while we also discuss implementation considerations  相似文献   
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133.
Inflammatory fibroid polyp (IFP) is a rare lesion of the gastroenteric tract more frequently occurring at the level of the stomach. The etiopathogenesis of IFP as well as the nature of the cells constituting these lesions remain unknown. Abdominal pain and anaemia due to chronic blood loss are the most common presenting features but neither radiology and CT scanning nor endoscopy are capable to achieve any conclusive diagnostic information. Histologic examination of the specimen obtained by endoscopic or surgical excision is considered to be the only way for the definitive exclusion of a neoplastic nature. A case of IFP treated by means of total gastrectomy is presented.  相似文献   
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135.
In this paper we deal with the problem of computing upward two-page book embeddings of Two Terminal Series-Parallel (TTSP) digraphs, which are a subclass of series-parallel digraphs. An optimal O(n) time and space algorithm to compute an upward two-page book embedding of a TTSP-digraph with n vertices is presented. A previous algorithm of Alzohairi and Rival [1] runs in O(n3) time and assumes that the input series-parallel digraph does not have transitive edges. An application of this result to a computational geometry problem is also discussed. More precisely, upward two-page book embeddings are used to deal with the upward point-set embeddability problem, i.e., the problem of mapping planar digraphs onto a given set of points in the plane so that all edges are monotonically increasing in a common direction. The equivalence between upward two-page book embeddability and upward point-set embeddability with at most one bend per edge on any given set of points is proved. An O(n log n)-time algorithm for computing an upward point-set embedding with at most one bend per edge for TTSP-digraphs is presented.  相似文献   
136.
Ni catalysts with nominal loadings ranging between 2.5 and 20 wt% were synthesized over perlite by wet impregnation, then filtered, washed and calcined at 500 °C. Chemical analyses performed by MP-AES revealed that the maximum Ni content loaded over perlite corresponded to ~15 wt%. Therefore, for comparison reasons, a Ni(20 wt%)/perlite catalyst was prepared by wetness impregnation without performing any washing treatment. The so prepared catalysts were tested in methane dry reforming without performing any pre-treatment reduction. The catalytic performances were compared by increasing the temperature from 500 up to 800 °C under the reaction mixture composed of 15 vol% CH4 + 15 vol% CO2/N2. Ni(15 wt%)/perlite was the most active catalyst among the series of monometallic samples. The effect of co-impregnating perlite with Ni and Zr or Ni and Ce precursors in order to obtain catalysts with final composition, Ni(15 wt%), 10 and 20 wt% as Zr or Ce, perlite (75 or 65 wt%) was, then, investigated. Characterizations performed by XRD, BET, DRS and H2-TPR evidenced that the physico-chemical and reduction properties are influenced by the Ni content and by the presence of zirconia and ceria oxides. It is worth of noting the increased reducibility of NiO species promoted by zirconia and ceria addition. The catalytic activity in the dry reforming of methane was also affected by the presence of doping oxides, in terms of enhanced CH4 and CO2 conversions and higher H2/CO atomic ratios. Runs tests at 700 °C for 12 h were carried out and the spent catalysts were analysed by TGA and TEM. Over Ni(15 wt%)/perlite large amount of amorphous carbon grows on the surface blocking the active centres, while zirconia and ceria doping improved the resistance to carbon poisoning favouring growing of filamentous carbon residues in small amount.  相似文献   
137.
Multiple endocrine neoplasia type 1 (MEN1) consists of benign, and sometimes malignant, tumors (often multiple in a tissue) of the parathyroids, enteropancreatic neuroendocrine system, anterior pituitary, and other tissues. Skin angiofibromas and skin collagenomas are common. Typically, MEN1 tumors begin two decades earlier than sporadic tumors. Because of tumor multiplicity and the tendency for postoperative tumor recurrence, specialized methods have been developed for preoperative and intraoperative localization of many MEN1-associated tumors. The MEN1 gene was recently isolated by positional cloning. This strategy progressively narrows the size of the candidate MEN1 gene interval on the chromosome and then finds and tests many or, if needed, all genes within that interval. The MEN1 gene was finally identified because it was the one gene that contained mutations in most DNAs from a test panel of MEN1 cases. It has been suggested that MEN1, like many hereditary cancer syndromes, is caused by mutation in a tumor suppressor gene that contributes to neoplasia when both gene copies in a tumor precursor cell have been sequentially inactivated ("two-hit" oncogenesis mechanism). Germline MEN1 mutations were found in most families with MEN1 and in most cases of sporadic MEN1. In addition, the MEN1 gene was the gene most likely to show acquired mutation in several sporadic or nonhereditary tumors-parathyroid adenomas, gastrinomas, insulinomas, and bronchial carcinoids. Most germline or acquired MEN1 mutations predicted truncation (and thus likely inactivation) of the encoded protein, supporting expectations for the "first hit" to a tumor suppressor gene. Testing for MEN1 germline mutation is possible in a research setting. Candidates for MEN1 mutation testing include patients with MEN1 or its phenocopies and first-degree relatives of persons with MEN1.  相似文献   
138.
La0.6Sr0.4Co0.2Fe0.8O3?δ (LSCF08), La0.6Sr0.4Co0.2Fe0.79Ni0.01O3?δ (LSCF08-Ni) and La0.6Sr0.4Co0.2Fe0.79Pd0.01O3?δ (LSCF08-Pd) perovskites were synthesized by Citrate-EDTA method, by using NiCl2 or PdCl2 as metal precursors, and their physicochemical properties were characterized by XRD, TGA, TPD and TPR. XRD data evidenced an expansion of the lattice parameters of LSCF08-Pd, while a contraction of the lattice occurred for LSCF08-Ni, with respect to the undoped LSCF, suggesting different oxygen vacancies content in the perovskite (confirmed by TGA) likely due to a different oxidation state of Ni and Pd species stabilized in the structure.TEM analyses performed over LSCF08-Pd revealed the presence of metallic Pd nanoparticles well dispersed in the matrix that accounts for the increased reducibility of the Co and Fe species with respect to LSCF08-Ni and undoped perovskite. AC impedance measurements that were carried out on symmetric cells consisting of LSCF-based materials deposited onto Ce0.8Gd0.2O2?δ (GDC) electrolyte proved the enhanced electrochemical performances of Ni/Pd doped LSCF.The electrochemical characterization of LSCF08, LSCF08-Ni and LSCF08-Pd electrodes was completed by performing cyclic voltammetry experiments in the range of temperature 600–800?°C, varying the potential (U) between 0.3?V and ?1?V, at scan rates in the range 1–50?mV?s?1 and working under flow of 0.7?vol% O2 in He (30?ml/min).  相似文献   
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