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11.
从计划角度重点分析了钢铁生产中炼钢、连铸、热轧三者之间联接的较高模式-直接热装轧制计划系统的实现方式,并给出了较为具体的方案。 相似文献
12.
F. M. Tukhtaboeva K. S. Davronov I. Zh. Kurbonbaev K. K. Kuchkarov 《Chemistry of Natural Compounds》2006,42(4):477-478
The protein composition of seeds treated with a suspension of ultradisperse iron was studied using electrophoresis on PAAG.
Changes were noted in the fractions with relative electrophoretic mobility (REM) 0.11 of water-soluble and REM 0.37 of buffer-soluble
An-9 cotton seed proteins.
__________
Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 384–385, July–August, 2006. 相似文献
13.
Iron oxide catalyst with spinel structure used for dehydrogenation of ethylbenzene is one kind of important catalyst in petrochemical industry. In this work several series of industrial catalyst were prepared with different components and different manufacturing processes. Mössbauer Spectroscopy has been used to determine the optimal components and the better manufacturing process for spinel structure formation. The results may prove useful for producing the industrial dehydrogenation catalyst with better catalytic property. 相似文献
14.
Michael Grätzel 《Journal of Sol-Gel Science and Technology》1994,2(1-3):673-677
Transparent nanocrystalline films of oxide semiconductors such as TiO2 and Fe2O3 have been prepared on a conducting glass support employing a sol-gel procedure. The films are composed of nanometer-sized particles sintered together to allow for percolative charge carrier transport. The internal surface of these films is very high, roughness factors of the order of 1000 being readily obtained. Electric polarization was applied for forward and reverse biasing of the films and the resulting optical changes have been analyzed to derive their flat band potential. Band gap excitation of such nanocrystalline semiconductors produces electron-hole pairs which migrate through the film to be collected as electric current. Steady state photolysis and time resolved laser techniques have been applied to scrutinize the mechanism of light induced charge separation within the nanostructure. When derivatized with a suitable chromophore, TiO2 films give extraordinary efficiencies for the conversion of incident photons into electric current, exceeding 90% for certain transition metal complexes within the wavelength range of their absorption band. The underlying physical principles of these astonishing findings will be discussed. Exploiting this discovery, we have developed a new type of photovoltaic device whose overall light to electric energy conversion yield is 10% under simulated AM 1.5 solar radiation. 相似文献
15.
采用低合金化、合锑多元复合孕育剂、扫描电镜、200h台架试验、以及l000h耐久试验等方法对新型薄壁柴油机缸体铸件进行了研制与应用试验.试验结果表明:碳当量控制在3.9%--4.1%时(与菲亚特缸体的碳当量大体相当),采用低合金化及合锑复合孕育剂,可稳定获得高强度铸件,抗拉强度σb>270MPa,硬度HB>210,白口倾向小,硬度差小于35HB,其性能均达到菲亚特缸体的性能要求.对无缸套缸体的缸壁表面进行激光处理,比传统缸套的耐磨性提高一倍以上.由于采用了无缸套缸体生产技术,简化了柴油机的结构,降低了柴油机的生产成本,提高了柴油机使用性能和技术含量. 相似文献
16.
微分脉冲溶出伏安法同时测定食品中的锌铁锰 总被引:7,自引:4,他引:3
在1%乙二胺-0.1mol/L酒石酸钠-pH11.82 Britton—Robinson缓冲溶液体系中用微分脉冲溶出伏安法同时测定锌、铁、锰三种微量元素。它们的峰电位分别为-1184,-1392和-1456mV(vs.Ag/AgCl);线性范围分别为:0.001—0.015,0.005—0.05和0.04—0.7μg/mL,最低检出浓度分别为0.0007,0.0014和0.0193μg/mL。本法操作简便、准确、灵敏度较高,用于食品中这三种元素的分析,结果令人满意。 相似文献
17.
崔新军 《济南大学学报(自然科学版)》2003,17(2):163-164
提出了利用电感耦合等离子发射光谱ICP -AES法测定原油中铁、钙元素含量的方法 ,考察了雾化压力、RF功率等对被测元素分析线强度的影响 ,确定了仪器的最佳使用条件。试验表明 ,该方法简便、快速、精密度和准确度均令人满意 ,能满足实际应用的要求 相似文献
18.
Benedict Ita P. Murugavel V. Ponnambalam A. R. Raju 《Journal of Chemical Sciences》2003,115(5-6):519-524
Fine powders of lanthanum iron oxide, LaFeO3, have been prepared by solid state reaction as well as sol-gel synthesis and nebulized spray pyrolysis. Structures, morphologies
and magnetic susceptibility measurements of these powders have been examined. The powders prepared by all the three low-temperature
routes contain nearly spherical particles with an average diameter of 40 nm. These samples show a lower Neel temperature than
the powder prepared by solid state reaction besides showing much lower magnetic susceptibility at low temperatures.
Dedicated to Professor C N R Rao on his 70th birthday 相似文献
19.
A. Paesano Jr. S. C. Zanatta S. N. De Medeiros L. F. CÓtica J. B. M. Da Cunha 《Hyperfine Interactions》2005,161(1-4):211-220
We have investigated the mechanosynthesis of gadolinium and yttrium iron garnets by high-energy ball-milling of α-Fe2O3 and Gd2O3 or α-Fe2O3 and Y2O3, respectively, followed by short thermal annealings conducted at moderate temperatures. The samples were characterized by X-ray diffraction and Mössbauer spectroscopy, in order to determine the influence of the milling time and annealing conditions on the final products. For as-milled samples of each rare-earth system, the results revealed the formation of perovskite phases, in relative amounts that depend on the milling time. The formation of garnet phases was observed in as-annealed samples treated at 1000°C for 2 h or 1100°C for 3 h, i.e., at very modest annealing requirements when compared with ordinary solid-state-reaction processes performed without previous high-energy milling. Also, the occurrence was verified of a milling time for which the relative amount of garnet phases formed by annealing was maximized. This time depends on the rare-earth composing the garnet phase and on the annealing temperature. 相似文献
20.
已有熔铁氨合成催化剂中添加稀土的报道.我们通过添加稀土得到了几种活性较高的催化剂,经进一步改进制备工艺(水浸处理后),活性又有所提高.本文利用XRD和AES等,对经水浸前后的含稀土催化剂的结构进行了测试,探讨了水浸后活性提高的原因. 相似文献