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51.
Healthy cattle are considered as reservoirs for a variety of Campylobacter species. To control the bacterial contamination in meat products, quantitative assessment of campylobacters in liver and gallbladder was carried out at an abattoir. Liver and bile samples were collected from 108 healthy beef cattle after evisceration and viable counts of campylobacters were determined by a direct-plating technique using modified Cefoperazone Charcoal Deoxycholate agar (mCCDA). The suspected colonies on the highest dilution plates were subjected to biochemical tests and PCR for identification. Campylobacter species were isolated from 49 (45%) bile and 6 (5%) liver specimens examined. Numbers of campylobacters in bile and liver ranged from log(10)3 to 7 (median 5) and log(10) 1 to 2 (median 1) cfu per ml and per g, respectively. These Campylobacter species were identified as C. fetus, C. jejuni, and C. coli. Multiple infections involving two species were observed in 16 cattle. C. fetus and C. jejuni were the predominant species in bile. Growth of C. fetus, C. jejuni, and C. coli in spiked bile samples revealed an initial exponential growth phase followed by a period with no apparent increase in colony count for 28 days. It appeared that these campylobacters can survive in bile for a long period. To determine transfer route of bacterial cells to the gallbladder, C. jejuni, C. fetus, or C. coli was inoculated intravenously in mice. The inoculated cells were recovered from bile, suggesting that the organism was transferred from the blood stream to bile duct in the liver. From these results, bile in cattle is considered to be an important contamination source of Campylobacter species in processing plants.  相似文献   
52.
Lithium non-stoichiometric Li[Lix(Ni1/3Co1/3Mn1/3)1−x]O2 materials (0 ≤ x ≤ 0.17) were synthesized using a spray drying method. The electrochemical properties and structural stabilities of the synthesized materials were investigated. The synthesized materials exhibited a hexagonal structure in all the x-value and the lattice parameters of the materials were gradually decreased with increasing x-value due to an increasing amount of Ni3+ ions for charge compensation. The capacity retention ability and rate capability of the stoichiometric Li(Ni1/3Co1/3Mn1/3)O2 material were improved by increasing x-value, the so-called overlithiation. We found that the overlithiated materials could keep more structural integrity than the stoichiometric one during electrochemical cyclings, which could be one of reasons for a better electrochemical properties of the overlithiated materials.  相似文献   
53.
In this paper, we re-examine the analysis on multinational firms and the theory of international trade and investment in the set-up with urban unemployment. A great majority of the recipient (host) countries are developing economies that are characterized by rural–urban migration in the face of urban unemployment. Thus, they have relatively developed urban sectors and less developed rural sectors. In this context we explore the implications of tariffs and taxes on the urban unemployment rate and national income.  相似文献   
54.
Aiming to distinguish sources and loads for the rapid scaling of renewable power sources, a novel power packet dispatching system has been proposed with a structure similar to those of communication systems. Accurate clock synchronization is necessary to achieve the exchange of information attached in a power packet. At the same time, the clock synchronization is an interesting topic for developing power packet dispatching between multi‐sender and a receiver. This work outlines the implementation of second‐order autonomously controlled clock synchronization into the power packet dispatching system. At first, we derive the second‐order controlled model of a digital clock synchronization method and analyze the stability of the developed model. Secondly, through experiments, it is shown that the information of power packets can be recognized correctly and the power can be distributed to directed loads. This paper demonstrates the validity of the asynchronous power packet dispatching based on our derived model. Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
55.
56.
Engineering and technology play an important role in strengthening the competitive power of a company and in surviving a severe competition in the world. About 70% of the total R&D investment in Japan comes from the private sector. It is the most important to decide which research projects have to be adopted for a future research out of proposals from divisions and sections in a company. The objective of this paper is to analyze the results of experts’ evaluation in selecting submitted proposals for R&D and to model the experts’ evaluation. This paper analyzes a research and development of a certain manufacturing company in a heavy metallurgy industry.We employed a principal component model, dual scaling, AHP and fuzzy regression analysis to analyze the results that experts evaluated proposed research projects for single or plural of fiscal years. The experts’ evaluation was pursued on the basis of (1) the objective of a research project, (2) its background, (3) its research contents, (4) the expected effect, (5) the possibility of obtaining patents, (6) project schedule, (7) developing cost, etc. The obtained model results in the same selection of projects as the experts did.  相似文献   
57.
Intramolecular cross-linking coupled with mass spectrometric identification of cross-linked amino acids is a rapid method for elucidating low-resolution protein tertiary structures or fold families. However, previous cross-linking studies on model proteins, such as cytochrome c and ribonuclease A, identified a limited number of peptide cross-links that are biased toward only a few of the potentially reactive lysine residues. Here, we report an approach to improve the diversity of intramolecular protein cross-linking starting with a systematic quantitation of the reactivity of lysine residues of a model protein, bovine cytochrome c. Relative lysine reactivities among the 18 lysine residues of cytochrome c were determined by the ratio of d0 and acetyl-d3 groups at each lysine after partial acetylation with sulfosuccinimidyl acetate followed by denaturation and quantitative acetylation of remaining unmodified lysines with acetic-d6 anhydride. These lysine reactivities were then compared with theoretically derived pKa and relative solvent accessibility surface values. To ascertain if partial N-acetylation of the most reactive lysine residues prior to cross-linking can redirect and increase the observable Lys-Lys cross-links, partially acetylated bovine cytochrome c was cross-linked with the amine-specific, bis-functional reagent, bis(sulfosuccinimidyl)suberate. After proteolysis and mass spectrometry analysis, partial acetylation was shown to significantly increase the number of observable peptides containing Lys-Lys cross-links, shifting the pattern from the most reactive lysine residues to less reactive ones. More importantly, these additional cross-linked peptides contained novel Lys-Lys cross-link information not seen in the non-acetylated protein and provided additional distance constraints that were consistent with the crystal structure and facilitated the identification of the proper protein fold.  相似文献   
58.
Telecommunication Systems - This paper proposes a Hadoop system that considers both slave server’s processing capacity and network delay for wide area networks to reduce the job processing...  相似文献   
59.
To realize the development of rechargeable sodium batteries, new positive electrode materials without less abundant elements are explored. Enrichment of sodium contents in host structures is required to increase the theoretical capacity as electrode materials, and therefore Na‐excess compounds are systematically examined in a binary system of Na2TiO3–NaMnO2. After several trials, synthesis of Na‐excess compounds with a cation disordered rocksalt structure is successful by adapting a mechanical milling method. Among the tested electrode materials, Na1.14Mn0.57Ti0.29O2 in this binary system delivers a large reversible capacity of ≈200 mA h g?1, originating from reversible redox reactions of cationic Mn3+/Mn4+ and anionic O2?/On? redox confirmed by X‐ray absorption spectroscopy. Holes in oxygen 2p orbitals, which are formed by electrochemical oxidation, are energetically stabilized by electron donation from Mn ions. Moreover, reversibility of anionic redox is significantly improved compared with a former study on a binary system of Na3NbO3–NaMnO2 tested as model electrode materials.  相似文献   
60.
In attempts to prepare layered Li[Ni1/3Co1/3Mn1/3]O2, hydrothermal method was employed. The hydrothermal precursor, [Ni1/3Co1/3Mn1/3](OH)2, was synthesized via a coprecipitation route. The sphere-shaped powder precursor was hydrothermally reacted with LiOH aqueous solution at 170 °C for 4 days in autoclave. From X-ray diffraction and scanning electron microscopic studies, it was found that the as-hydrothermally prepared powders were crystallized to layered α-NaFeO2 structure and the particles had spherical shape. The as-prepared Li[Ni1/3Co1/3Mn1/3]O2 delivered an initial discharge of about 110 mA h g−1 due to lower crystallinity. Heat treatment of the hydrothermal product at 800 °C was significantly effective to improve the structural integrity, which consequently affected the increase in the discharge capacity to 157 (4.3 V cut-off) and 182 mA h g−1 (4.6 V cut-off) at 25 °C with good reversibility.  相似文献   
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