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81.
In the present study, a composite made of conducting polymer, poly(3,4-ethylenedioxythiophene) (PEDOT), and a biodegradable hydrogel of poly(aspartic acid) (PASP) were electrochemically interpenetrated with poly(hydroxymethyl-3,4-ethylenedioxythiophene) (PHMeDOT) to prepare a new interpenetrated polymer network (IPN). Different cross-linker and PEDOT MPs contents, as well as different electropolymerization times, were studied to optimize the structural and electrochemical properties. The properties of the new material, being electrically conductive, biocompatible, bioactive, and biodegradable, make it suitable for possible uses in biomedical applications.  相似文献   
82.
Near infra‐red reflectance spectroscopy (NIRS) was used to develop calibration equations to measure nitrogen and ash contents in grassland samples. Four populations of samples were collected or prepared: total herbage, with a heterogeneous and complex botanical composition, and its botanical components (grasses, legumes and forbs). A set of samples from each population was selected to develop the specific calibration equations using three mathematical data treatments (log 1/R, first and second derivative). Six and seven wavelengths were selected by multiple regression to predict nitrogen and ash contents, respectively. Calibration equations were evaluated by comparing the values obtained by reference methods (Kjeldahl test and dry ashing measurements) with those predicted by NIRS. The three data treatments generally provided similar results as regards estimations of nitrogen contents. The correlation coefficients varied from 0.94 to 0.98, and the standard errors of prediction ranged from 1.10 to 1.49 g kg−1 (total herbage), from 0.73 to 0.98 g kg−1 (grasses), from 0.99 to 1.30 g kg−1 (legumes) and from 0.76 to 0.80 g kg−1 (forbs). The most suitable treatments to predict ash contents were log 1/R and the first derivative. The best performance was obtained for legumes, using log 1/R, with a correlation coefficient of 0.95 and a standard error of prediction of 3.54 g kg−1. The calibration equations became more accurate as the components of the sets of samples became botanically simpler. Prediction accuracy was greater when the specific calibration equations for each population of samples were used. © 1999 Society of Chemical Industry  相似文献   
83.
This paper introduces RuleSIM, a toolkit comprising different simulation tools specifically designed to aid researchers concerned about spam‐filtering throughput. RuleSIM allows easily designing, developing, simulating and comparing new scheduling heuristics using different filters and sets of e‐mails. Simulation results can be both graphically analysed, by using different complementary views, and quantitatively compared through several measures. Moreover, the underlying RuleSIM API can be easily integrated with third‐party Java optimization platforms to facilitate debugging and achieve better configurations for rule scheduling. RuleSIM is free software distributed under the terms of GNU Lesser General Public License, and both source code and documentation are publicly available at https://github.com/rulesim/v2.0 . Copyright © 2015 John Wiley & Sons, Ltd.  相似文献   
84.
We investigated the possible association between delta and gamma2 subunits in native GABA(A) receptors, from different rat brain regions, using subunit-specific anti-delta and anti-gamma2 antibodies. Previous reports have provided somewhat controversial results, indicating both the presence and the absence of association between these two subunits in native receptors. Our results indicate the absence of co-localization between delta and gamma2 subunits. In immunoprecipitation experiments, anti-delta antibody consistently immunoprecipitated [3H]muscimol binding activity (GABA binding sites) from all brain areas tested (10-20% of the total binding). However, under the same conditions, no significant [3H]flumazenil or [3H]ethyl 8-azido-6-dihydro-5-methyl-6-oxo-4H-imidazol[1,5-a]-[1,4]benzodiazepine- 3-carboxylate (Ro15-4513) binding (benzodiazepine binding sites) activity was detected in the immunopellets. These results indicate the absence of association between delta and gamma2 subunits. This question was directly addressed by immunopurification and Western blot experiments. As expected, no gamma2 subunits were detected in anti-delta immunoaffinity purified receptors. Conversely, no delta subunits were identified in anti-gamma2 immunopurified receptors. Thus, these results demonstrate the absence of association between delta and gamma2 subunits in native GABA(A) receptors. Finally, our results also indicate the relevance of the solubilization conditions on the apparent association between different subunits of the native GABA(A) receptor complex.  相似文献   
85.
The aim of this study was to analyze factors affecting mobilization and engraftment in 40 children undergoing autologous peripheral blood progenitor cell transplantation for different malignancies: 19 patients with haematological malignancies and 21 patients with solid tumors. Patients received 4-5 days of rhG-CSF (12 micrograms/kg/day) subcutaneously. Apheresis was performed by continuous flow blood cell separation beginning on the fifth day of rhG-CSF. For patients weighing < or = 25 kg, the extracorporeal line was primed with irradiated red blood cells. After myeloablative conditioning regimens, patients were grafted with 7.21 +/- 7.8 x 10(6)/kg CD34+ cells. Days to achieve an absolute neutrophil count > 0.5 x 10(9)/1 and a platelet count > 20 x 10(9)/1 without platelet support were 9.50 +/- 1.2 (range 7-13) and 18.1 +/- 8.3 (range 9-37), respectively. The number of CD34+ cells infused was highly correlated with engraftment kinetics (P = 0.0001). The patient's body weight and the number of previous chemotherapy courses had a negative influence on CD34+ cells collected.  相似文献   
86.
In this work we address the issue of parameter subset selection within the scope of activated sludge model calibration. To this end, we evaluate two approaches: (i) systems analysis and (ii) experience-based approach. The evaluation has been carried out using a dynamic model (ASM2d) calibrated to describe nitrogen and phosphorus removal in the Haaren WWTP (The Netherlands). The parameter significance ranking shows that the temperature correction coefficients are among the most influential parameters on the model output. This outcome confronts the previous identifiability studies and the experience based approaches which excluded them from their analysis. Systems analysis reveals that parameter significance ranking and size of the identifiable parameter subset depend on the information content of data available for calibration. However, it suffers from heavy computational demand. In contrast, although the experience-based approach is computationally affordable, it is unable to take into account the information content issue and therefore can be either too optimistic (giving poorly identifiable sets) or pessimistic (small size of sets while much more can be estimated from the data). An appropriate combinations of both approaches is proposed which offers a realistic (doable) and sound approach for parameter subset selection in activated sludge modelling.  相似文献   
87.
Estuaries are among the most productive ecosystems and simultaneously among the most threatened by conflicting human activities which damage their ecological functions, namely their nursery role for many fish species. A thorough assessment of the anthropogenic pressures in Portuguese estuarine systems (Douro, Ria de Aveiro, Mondego, Tejo, Sado, Mira, Ria Formosa and Guadiana) was made applying an aggregating multi-metric index, which quantitatively evaluates influences from key components: dams, population and industry, port activities and resource exploitation. Estuaries were ranked from most (Tejo) to least pressured (Mira), and the most influential types of pressure identified. In most estuaries overall pressure was generated by a dominant group of pressure components, with several systems being afflicted by similar problematic sources. An evaluation of the influence of anthropogenic pressures on the most important sparidae, soleidae, pleuronectidae, moronidae and clupeidae species that use these estuaries as nurseries was also performed. To consolidate information and promote management an ecological conceptual model was built to identify potential problems for the nursery function played by these estuaries, identifying pressure agents, ecological impacts and endpoints for the anthropogenic sources quantified in the assessment. This will be important baseline information to safeguard these vital areas, articulating information and forecasting the potential efficacy of future management options.  相似文献   
88.
Hearts of newborn mice were cut into small pieces, the fragments transplanted under the ear skin of adult recipients, and the graft survival followed visually (pulsating fragments were considered viable). Donor-recipient combinations were chosen from H-2 congenic (recombinant and mutant) strains in such a way as to provide differences in the entire H-2 complex or in only a small portion of it. The data obtained indicate that a difference between the donor and the recipient in either K, D, or I regions suffices for the rejection of the heart fragments. The rejection is often accompanied by the production of antibodies against classical H-2 antigens (in the case of K- or D-region disparities) or Ia antigens (in the case of I region disparities). In some instances, the antibodies persist in the recipient for more than 50 days. We conclude from these experiments that the same loci that cause acute skin graft rejection (H-2K, H-2D, and H-2I) are responsible for heart graft rejection. Furthermore, we also conclude that serologically Ia-negative tissues may carry Ia antigens in sufficient quantities to stimulate the production of Ia antibodies.  相似文献   
89.
The high-temperature deformation behavior of two ultrahigh boron steels containing 2.2 pct and 4.9 pct B was investigated. Both alloys were processedvia powder metallurgy involving gas atomization and hot isostatic pressing (hipping) at various temperatures. After hipping at 700 °C, the Fe-2.2 pct B alloy showed a fine microstructure consisting of l-μm grains and small elongated borides (less than 1μm) . At 1100 °C, a coarser microstructure with rounded borides was formed. This alloy was superplastic at 850 °C with stress exponents of about two and tensile elongations as high as 435 pct. The microstructure of the Fe-4.9 pct B alloy was similar to that of the Fe-2.2 pct B alloy showing, in addition, coarse borides. This alloy also showed low stress exponent values but lacked high tensile elongation (less than 65 pct), which was attributed to the presence of stress accumulation at the interface between the matrix and the large borides. A change in the activation energy value at theα-γ transformation temperature was seen in the Fe-2.2 pct B alloy. The plastic flow data were in agreement with grain boundary sliding and slip creep models. J.A. JIMéNEZ, Postdoctoral Fellow, formerly with Centro Nacional de Investigaciones Metalurgicas, C.S.I.C.  相似文献   
90.
It is shown that densification of white cast iron powders under stress can be enhanced by multiple phase transformations through thermal cycling. This enhancement occurs by accelerated creep flow during phase changes (transformation superplasticity). The approximate stress range where transformation-assisted densification can occur is shown to be between 1.7 MPa (250 psi) and 34.5 MPa (5000 psi). Below 1.7 MPa insufficient strain occurs during phase transformation to cause significant densification even after many transformation cycles. Above 34.5 MPa, densification occurs principally by normal slip creep. Transformation warm pressing of white cast iron powders leads to dense compacts at low pressures and short times. In addition, because the transformation temperature is low, the ultrafine structures existing in the original powders are retained in the densified compacts. formerly with the Department of Materials Science and Engineering, Stanford University,  相似文献   
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