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51.
M. Bäcker S. Beging M. Biselli J. Wang W. Zang M.J. Schöning 《Electrochimica acta》2009,54(25):6107-9678
In this study, a concept for a silicon-based modular solid-state sensor system for inline multi-parameter monitoring of cell-culture fermentation processes is presented. The envisaged multi-parameter sensor system consists of two identical sensor modules and is intended for continuous quantification of up to five (bio-)chemical and physical parameters, namely, glucose and glutamine concentration, pH value, electrolyte conductivity and temperature by applying different transducer principles and/or different operation modes. Experimental results for the field-effect electrolyte-insulator-semiconductor (EIS) sterilisable pH sensor and electrolyte conductivity sensor based on interdigitated electrodes are presented. The ongoing autoclaving does not have any significant impact on the pH-sensitive properties of a Ta2O5-gate EIS sensor. Even after 30 autoclaving cycles, the pH sensors show a clear pH response and nearly linear calibration curve with a slope of 57 ± 1 mV/pH. Additional scanning electron microscopy and ellipsometric investigations do not show any visible surface degradation or changes in the thickness of the pH-sensitive Ta2O5 layer. The preliminary results demonstrate the suitability of the developed EIS sensor for an inline pH measurement during a fermentation process. In addition, interdigitated electrodes of different geometries serving as electrolyte conductivity sensor have been tested for measurements in relatively high ionic-strength solutions. 相似文献
52.
镉镍电池电解液中锂含量的测定 总被引:2,自引:0,他引:2
研究与应用氧化亚氮———乙炔火焰原子吸收法测定镉镍电池电解液中的锂含量。介绍了锂的最佳测定条件及呈良好线性范围的浓度 ,该方法具有很高的灵敏度 ,选择性和重现性好、干扰小 ,并具有操作简便、易掌握、分析周期短等特点。相对标准偏差RSD<1.00 %(n=10) ,标准加入回收率均在97.00 %~102.00 %(n=4)范围内(回收率要求符合课题指标)。方法的精确度和准确度均能满足镉镍电池研制工作的要求 ,结果令人满意。 相似文献
53.
James P. Coleman Anne T. Lynch Puttanachetty Madhukar John H. Wagenknecht 《Solar Energy Materials & Solar Cells》1999,56(3-4)
We describe herein some of our initial studies in pursuit of a simple, economical method of mass producing electrochromic displays. The approach we have taken is to print the display on polymer film utilizing commercially available conductive inks in an interdigitated electrode structure with a conductive metal oxide powder, dispersed in a polymer binder, as the electrode surface. A range of electrochromic materials suitable for use with an aqueous gel electrolyte have been explored and examples presented. 相似文献
54.
55.
Performance of carbon-carbon supercapacitors based on organic, aqueous and ionic liquid electrolytes 总被引:1,自引:0,他引:1
Andrzej Lewandowski Angelika Olejniczak Maciej Galinski Izabela Stepniak 《Journal of power sources》2010,195(17):5814-159
Properties of capacitors working with the same carbon electrodes (activated carbon cloth) and three types of electrolytes: aqueous, organic and ionic liquids were compared. Capacitors filled with ionic liquids worked at a potential difference of 3.5 V, their solutions in AN and PC were charged up to the potential difference of 3 V, classical organic systems to 2.5 V and aqueous to 1 V. Cyclic voltammetry, galvanostatic charging/discharging and impedance spectroscopy were used to characterize these capacitors. The highest specific energy was recorded for the device working with ionic liquids, while the highest power is characteristic for the device filled with aqueous H2SO4 electrolyte. Aqueous electrolytes led to energy density an order of magnitude lower in comparison to that characteristic of ionic liquids. 相似文献
56.
ZhenLan Li Hary Devianto Sung Pil Yoon Jonghee Han Tae-Hoon Lim Ho-In Lee 《International Journal of Hydrogen Energy》2010
An active and tolerant Ni-based catalyst for methane steam reforming in direct internal reforming molten carbonate fuel cells (DIR-MCFCs) was developed. Deactivation of reforming catalysts by alkali metals from the electrolyte composed of Li2CO3 and K2CO3 is one of the major obstacles to be overcome in commercialization of DIR-MCFCs. Newly developed Ni/MgSiO3 and Ni/Mg2SiO4 reforming catalysts show activities of ca. 80% methane conversion. Subsequent to electrolyte addition to the catalyst, however, the activity of Ni/Mg2SiO4 decreases to ca. 50% of its initial value, whereas Ni/MgSiO3 catalyst retains its initial activity. Results obtained from temperature-programmed reduction and X-ray photoelectron spectroscopy identify unreduced Ni3+ as a decisive factor in keeping catalytic activity from the electrolyte. 相似文献
57.
Xiaoyan Ji 《Chemical engineering science》2008,63(1):131-140
Ion-based SAFT2 is extended to the properties of aqueous multiple-salt solutions at ambient and elevated temperatures and pressures. The short-range interactions between two different cations are allowed to obtain better representations of the solution properties. The adjustable parameter used in the mixing rule for the segment energy is fitted to the experimental osmotic coefficients of two-salt solutions containing one common anion at various temperatures and low pressures. The predictions of the osmotic coefficients, densities, and activity coefficients of multiple-salt solutions including brine/seawater are found to agree with experimental data. 相似文献
58.
Ionic liquid electrolytes based on 1-vinyl-3-alkylimidazolium iodides for dye-sensitized solar cells 总被引:1,自引:1,他引:0
Five new ionic liquids of 1-vinyl-3-alkylimidazolium iodide were synthesized to develop novel electrolytes for dye-sensitized solar cells. The effects of photovoltaic characteristics of the cell and the ionic liquid features such as viscosity and ionic conductivity were described. The 1-vinyl-3-alkylimidazolium cation volume was calculated by quantum chemistry method. The linear dependence of photon-to-current conversion efficiency on the non-solvated cation volume was revealed. After lithium iodide was added to 1-vinyl-3-alkylimidazolium salts as electrolytes, except the photovoltage, the photocurrent, fill factor and photon-to-current efficiency were improved correspondingly. 相似文献
59.
A polymerizable monomer, diphenylamine (DPAn), is reported to act as a safety electrolyte additive for overcharge protection of 3.6 V-class lithium ion batteries. The experimental results demonstrated that the DPAn monomer could be electro-polymerized to form a conductive polymer bridging between the cathode and anode of the battery, and to produce an internal current bypass to prevent the batteries from voltage runaway during overcharge. The charge–discharge tests of practical LiFePO4/C batteries indicated that the DPAn additive could clamp the cell's voltage at the safe value less than 3.7 V even at the high rate overcharge of 3 C current, meanwhile, this monomer molecule has no significant impact on the charge–discharge performance of the batteries at normal charge–discharge condition. 相似文献