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31.
During the excavation of different segments of the Variante de Pajares tunnels by means of single shield TBMs (tunnel boring machines), methane has been found. The analysis of the recorded data has allowed to prove that the natural gas emission in a tunnel excavating through Carboniferous strata is similar to that which occurs in an underground coal mine. In this paper, two mining parameters for the characterisation of methane emission, the methane emission rate (volume of methane emitted per ton of excavated rock) and average methane flow rate (volume of methane emitted per day), are introduced. Following, using the measurements of TBM advancing rate, quantity air flow and methane concentration carried out during the tunnel excavation through San Emiliano geological formation these two parameters have been determined for the tunnel. The results were very similar to those observed in coal mines, which means that mining experience can be used in order to predict the methane inflow into a tunnel excavated through a Carboniferous rockmass which is very useful for the design of the ventilation system, something very significant for safety.  相似文献   
32.
BACKGROUND: In Mediterranean countries, olive tree pruning provides a widely available renewable agricultural residue with, currently, no industrial application. This residue could provide feedstock for the bioethanol industry. In the present study, olive tree pruning biomass pretreated with both ‘liquid hot water’ and ‘dilute‐sulfuric acid’ was tested as a substrate for ethanol production. Three different process configurations, separate hydrolysis and fermentation (SHF), simultaneous saccharification, fermentation and prehydrolysis (PSSF), and simultaneous saccharification and fermentation (SSF), were compared at different water‐insoluble solids concentrations. RESULTS: High ethanol concentration of about 3.7% (v/v) was obtained by separate hydrolysis and fermentation or prehydrolysis and simultaneous saccharification and fermentation of liquid hot water pretreated at 23% (w/w) substrate loading. CONCLUSION: The nature of the pretreated residue allows high substrate concentration (≥17% w/w) to be used in the enzymatic hydrolysis step. Substrate loading of 17% DM has been shown to provide a compromise between hydrolysis efficiency and glucose concentrations for the same enzyme/substrate ratio. Prehydrolysis prior to simultaneous saccharification and fermentation facilitated SSF performance at high substrate loading on liquid hot water pretreated olive pruning residue. This effect was not observed with dilute‐acid pretreated substrate. Copyright © 2011 Society of Chemical Industry  相似文献   
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Resumen Se calculan las distribuciones menos informativas cuando se utilizan como medidas de información la entropía informacional de Onicescu, tanto si el espacio de estados Θ es continuo (intervalo deR) como si es discreto y suponiendo que el decisor posee información acerca de algunas características de la distribución a priori (monotonías de la función de densidad, probabilidades de subconjuntos de Θ, monotonías o cotas de la razón de fallo).
The less informative distributions are calculated when we use as measure of information the useful entropy and the informational energy of Onicescu whether the espace of states is continuos (interval ofR) or it is discrete, and suppossing that the decider possesses information about some characteristics of the a priori distribution (mononies of the probability density function, probabilities of subsets, monotonies or boundaries on failures ratio).
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35.
The polyesterification reaction of maleic anhydride and 1,4-butylene glycol was carried out, using p-toluensulphonic acid as catalyst. The resulting material was characterized by IR and H1-NMR spectroscopy, end group analysis, and gel permeation chromatography. It is shown that there is a relationship between maleate to fumarate isomerization and steric interaction among condensed groups on the one hand and the tendency of the reacting system to crosslink or gel.  相似文献   
36.
The polycondensation reaction between maleic anhydride and 1,6-hexanediol, with p-toluenesulfonic acid as catalyst has been carried out. The product has been analyzed spectroscopically and the molecular weight determined by endgroup analysis and gel permeation chromatography. The influence of spatial interactions between condensed groups on the isomerization of maleate into fumarate is discussed, as well as the effects of even- and odd- numbered carbon atom glycols. © 1993 John Wiley & Sons, Inc.  相似文献   
37.
The stochastic dynamic programming approach outlined here, makes use of the scenario tree in a back-to-front scheme. The multi-period stochastic problems, related to the subtrees whose root nodes are the starting nodes (i.e., scenario groups), are solved at each given stage along the time horizon. Each subproblem considers the effect of the stochasticity of the uncertain parameters from the periods of the given stage, by using curves that estimate the expected future value (EFV) of the objective function. Each subproblem is solved for a set of reference levels of the variables that also have nonzero elements in any of the previous stages besides the given stage. An appropriate sensitivity analysis of the objective function for each reference level of the linking variables allows us to estimate the EFV curves applicable to the scenario groups from the previous stages, until the curves for the first stage have been computed. An application of the scheme to the problem of production planning with logical constraints is presented. The aim of the problem consists of obtaining the planning of tactical production over the scenarios along the time horizon. The expected total cost is minimized to satisfy the product demand. Some computational experience is reported. The proposed approach compares favorably with a state-of-the-art optimization engine in instances on a very large scale.  相似文献   
38.
Systemic lupus erythematosus (SLE) is a complex autoimmune disease that has heterogeneous clinical manifestation with diverse patterns of organ involvement, autoantibody profiles and varying degrees of severity of disease. Research and clinical experience indicate that different subtypes of SLE patients will likely benefit from more tailored treatment regimes, but we currently lack a fast and objective test with high enough sensitivity to enable us to perform such sub-grouping for clinical use. In this article, we review how proteomic technologies could be used as such an objective test. In particular, we extensively review many leukocyte surface markers that are known to have an association with the pathogenesis of SLE, and we discuss how these markers can be used in the further development of a novel SLE-specific antibody leukocyte capture microarray. In addition, we review some bioinformatics challenges and current methods for using the data generated by these cell-capture microarrays in clinical use. In a broader context, we hope our experience in developing a disease specific cell-capture microarray for clinical application can be a guide to other proteomic practitioners who intend to extend their technologies to develop clinical diagnostic and prognostic tests for complex diseases.  相似文献   
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Mesothelial cells form the mesothelium, a simple epithelium lining the walls of serous cavities and the surface of visceral organs. Although mesothelial cells are phenotypically well characterized, their immunoregulatory properties remain largely unknown, with only two studies reporting their capacity to inhibit T cells through TGF-β and their consumption of L-arginine by arginase-1. Whether human mesothelial cells can suppress other immune cells and possess additional leukosuppressive mechanisms, remain to be addressed to better delineate their therapeutic potential for cell therapy. Herein, we generated secretomes from omental mesothelial cells (OMC) and assess their capacity to inhibit lymphocytes proliferation, suppress activated T and B cells, as well as to modify macrophage activation markers. The secretome from mesenchymal stromal cells (MSC) served as a control of immuno-suppression. Although OMC and MSC were phenotypically divergent, their cytokine secretion patterns as well as expression of inflammatory and immunomodulary genes were similar. As such, OMC- and MSC-derived secretomes (OMC-S and MSC-S) both polarized RAW 264.7 macrophages towards a M2-like anti-inflammatory phenotype and suppressed mouse and human lymphocytes proliferation. OMC-S displayed a strong ability to suppress mouse- and human-activated CD19+/CD25+ B cells as compared to MSC-S. The lymphosuppressive activity of the OMC-S could be significantly counteracted either by SB-431542, an inhibitor of TGFβ and activin signaling pathways, or with a monoclonal antibody against the TGFβ1, β2, and β3 isoforms. A strong blockade of the OMC-S-mediated lymphosuppressive activity was achieved using L-NMMA, a specific inhibitor of nitric oxide synthase (NOS). Taken together, our results suggest that OMC are potent immunomodulators.  相似文献   
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