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61.
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Performance optimization of integrated gas and power within microgrids using hybrid PSO–PS algorithm
In this paper, a hybrid algorithm consisting of particle swarm optimization and pattern search algorithm is proposed to evaluate and optimize the design and operation of microgrids (MGs) in combined gas and power networks. Key performance indicators (KPIs) are modeled and proposed to evaluate and assess MGs. The paper begins by proposing a comprehensive study to define KPIs, which are used to evaluate the following MG parameters: economical efficiency, reliability, environmental conservation, and power quality. Multi‐objective evaluation functions are then developed by building a relationship matrix of MG and KPI components. The results are then displayed as optimized power generation percentages for each technology with values for four KPI categories: cost, quality, reliability and environmental friendliness. Two case studies are examined in this paper; both the province of Ontario and Toronto regional zone under all system parameters with varying percentage of generation via gas technology. Results indicated that the optimal scenario for both Ontario and Toronto was achieved at hybrid PSO–patern search percentage generation via gas technology with improved cost KPI and other KPIs remaining approximately constant. Copyright © 2016 John Wiley & Sons, Ltd. 相似文献
63.
研制了一种新型的与可伐熔封的ZnO-Al_2O_3-B_2O_3-SiO_2系微晶玻璃,研究了不同工艺条件下微晶玻璃与可伐合金间的润湿角大小,结果表明,熔封气氛和熔封温度对润湿性能影响很大,熔封时间影响最小.采用最佳的工艺条件,其润湿性能与现有的其它玻璃润湿性能相似.同时发现玻璃与可伐合金间的润湿角保持在10°~30°之间能得到质量良好的熔封产品.在基本不改变传统工艺制度的条件下,可完成锌铝硼硅系微晶玻璃与可伐合金的熔封,即利用排蜡过程同时完成微晶玻璃的形核,熔封后在稍低温度保温或减慢冷却速度可以完成微晶玻璃的结晶过程.锌铝硼硅系微晶玻璃与预氧化可伐合金的封接依靠玻璃中的SiO_2与FeO或Fe_3O4发生界面反应形成牢固的结合. 相似文献
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Geologic materials are an important source of airborne particulate matter less than 10 microm aerodynamic diameter (PM10), but the contribution of contaminated soil to concentrations of Pb and other trace elements in air has not been documented. To examine the potential significance of this mechanism, surface soil samples with a range of bulk soil Pb concentrations were obtained near five industrial facilities and along roadsides and were resuspended in a specially designed laboratory chamber. The concentration of Pb and other trace elements was measured in the bulk soil, in soil size fractions, and in PM10 generated during resuspension of soils and fractions. Average yields of PM10 from dry soils ranged from 0.169 to 0.869 mg of PM10/g of soil. Yields declined approximately linearly with increasing geometric mean particle size of the bulk soil. The resulting PM10 had average Pb concentrations as high as 2283 mg/kg for samples from a secondary Pb smelter. Pb was enriched in PM10 by 5.36-88.7 times as compared with uncontaminated California soils. Total production of PM10 bound Pb from the soil samples varied between 0.012 and 1.2 mg of Pb/kg of bulk soil. During a relatively large erosion event, a contaminated site might contribute approximately 300 ng/m3 of PM10-bound Pb to air. Contribution of soil from contaminated sites to airborne element balances thus deserves consideration when constructing receptor models for source apportionment or attempting to control airborne Pb emissions. 相似文献
66.
Pharmacological studies have revealed a non-beta1, beta2 or beta3 adrenergic receptor that mediates tachycardia in rat and human atria. The present studies utilized transgenic mice that lack the rodent beta3 receptor to explore, in a more definitive fashion, whether a non-beta1, beta2 or beta3 receptor can mediate atrial tachycardia. Insofar as the rat stomach fundus possesses a beta3 receptor mediating relaxation, we examined the stomach fundus from beta3 receptor knockout mice for the presence or absence of the beta3 relaxant receptor. Contractile responses to carbamylcholine were similar in potency and magnitude between mouse stomach fundus from wild type and beta3 receptor knockout animals. However, the classical beta3 receptor agonist CL316243, (10(-8)-10(-6)M) relaxed stomach fundus from wild type mice, but not from the beta3 receptor knockout animals. These data provide functional evidence for the absence of the beta3 receptor in beta3 receptor knockout animals and support the role of beta3 receptors mediating relaxation in mouse stomach fundus. Atria from mice lacking the beta3 receptor responded similarly (in potency and maximal increase in heart rate) to isoproterenol (10(-9)-10(-6)M) as atria from wild type mice. Furthermore, propranolol (3 x 10(-7) M) produced a dextral shift in the concentration response to isoproterenol in atria from both the beta3 receptor knockout and wild type mice with negative log K(B) values of 8.03 and 8.09, respectively. Thus, beta receptors mediating tachycardia to isoproterenol are intact and respond similarly in atria from both knockout and wild type mice. Furthermore, CGP12177, a prototypic 'atypical' beta receptor agonist produced tachycardia with a similar EC50 and maximal response in atria from both the wild type and beta3 receptor knockout mice. Cyanopindolol was a partial agonist relative to CGP12177 in both wild type and beta3 receptor knockout mice. Tachycardia to CGP12177 and cyanopindolol was not blocked by propranolol (3 x 10(-7) M) in atria from either group. These data provide definitive evidence that the receptor mediating tachycardia to CGP12177 and to cyanopindolol in atria from the transgenic beta3 receptor knockout mice is neither the beta1, beta2, nor beta3 adrenergic receptor. 相似文献
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68.
We examined whether timeline icons improved older and younger adults' comprehension of medication information. In Experiment 1, comprehension of instructions with the icon (icon/text format) and without the icon (text-only format) was assessed by questions about information that was (a) implicit in the text but depicted explicitly by the icon (total dose in a 24 hour period), (b) stated and depicted in the icon/text condition (medication dose and times), and (c) stated but not depicted by the icon (e.g., side effects). In a separate task, participants also recalled medication instructions (with or without the icon) after a study period. We found that questions about dose and time information were answered more quickly and accurately when the icon was present in the instructions. Notably, icon benefits were greater for information that was implicit rather than stated in the text. This finding suggests that icons can improve older and younger adults' comprehension by reducing the need to draw some inferences. The icon also reduced effective study time (study time per item recalled). In Experiment 2, icon benefits did not occur for a less integrated version of the timeline icon that, like the text, required participants to integrate dose and time information in order to identify the total daily dose. The integrated version of the icon again improved comprehension, as in Experiment 1, as well as drawing inferences from memory. These findings show that integrated timeline icons improved comprehension primarily by aiding the integration of dose and time information. These findings are discussed in terms of a situation model approach to comprehension. 相似文献
69.
70.
HS Hiemstra PA van Veelen NC Schloot A Geluk KE van Meijgaarden SJ Willemen JA Leunissen WE Benckhuijsen R Amons RR de Vries BO Roep TH Ottenhoff JW Drijfhout 《Canadian Metallurgical Quarterly》1998,161(8):4078-4082
Progress has recently been made in the use of synthetic peptide libraries for the identification of T cell-stimulating ligands. T cell epitopes identified from synthetic libraries are mimics of natural epitopes. Here we show how the mimicry epitopes obtained from synthetic peptide libraries enable unambiguous identification of natural T cell Ags. Synthetic peptide libraries were screened with Mycobacterium tuberculosis-reactive and -autoreactive T cell clones. In two cases, database homology searches with mimicry epitopes isolated from a dedicated synthetic peptide library allowed immediate identification of the natural antigenic protein. In two other cases, an amino acid pattern that reflected the epitope requirements of the T cell was determined by substitution and omission mixture analysis. Subsequently, the natural Ag was identified from databases using this refined pattern. This approach opens new perspectives for rapid and reliable Ag definition, representing a feasible alternative to the biochemical and genetic approaches described thus far. 相似文献