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通过在铅锑精矿焙烧时加入一定量的氧化锌或氧化钙,使铅锑精矿在灼烧过程中的单质硫、有机质、硫化物、碳充分焙烧,然后采用王水分解矿样,活性炭动态吸附富集金,灰化除碳,王水溶解,原子吸收光度法测定铅锑精矿中金含量,方法快速、准确,同时适用于含碳、硫较高焙烧时易结块的精矿样品。 相似文献
93.
The Turkish wind energy industry is one of the most competitive and fastest growing industries in the energy sector. Industrial energy demands, Kyoto agreement and carbon trade are shown as probable causes. Currently, Turkey has a total installed capacity of about 48.5 GW for electricity from all energy sources. High energy prices and unstable suppliers have stimulated Turkey's growing interest in wind business and wind power. This paper analyzes Turkey's wind energy future perspective and power generation strategy with a view to explaining Delphi approach to wind energy development. In this study, the two‐round Delphi survey was conducted by experts to determine and measure the expectations of the sector representatives through online surveys where a total of 70 experts responded from 24 different locations. The majority of the Delphi survey respondents were from 23 different universities (60%), electricity generation industries (21%), two different governmental organizations (11%), nongovernmental organizations (6%) and other institutions (2%). The article discusses not only the expert sights on wind energy technology but also all bibliometrical approaches. The results showed that Turkey's wind power installed capacity is expected to exceed 40 GW by the end of the 2020 s and in the middle of the 2030 s, and Turkey would be the European leading country in the field of electricity generation from the wind. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
94.
通过半动态淋滤试验,研究淋滤液初始pH=2,4,7时水泥固化铅污染土的强度、微观和钙溶出特性。无侧限抗压强度试验及钙溶出率(CFRCa)结果表明:半动态淋滤试验使试样无侧限抗压强度(qu)较标准养护39 d试样降低了1%~42%;淋滤液初始pH=2时,CFRCa为pH=4或7时的2~7倍,而pH=4与7时qu及CFRCa差别均不明显;水泥掺量由12%提高到18%时,qu增大了35%~98%,CFRCa降低了40%~58%;固化铅污染土较固化未污染土,其qu小50%~68%,而CFRCa大29%~175%。试样无侧限抗压强度比qr(淋滤后试样qu/标准养护39 d试样qu)与CFRCa在双对数坐标下呈现良好线性关系:随CFRCa增大,qr减小,说明钙的溶出是控制固化污染土/未污染土强度的主要因素之一。X射线衍射、扫描电镜及压汞试验结果表明,高浓度铅抑制水泥水化/火山灰反应,固化铅污染土与固化未污染土孔隙分布分别呈单峰和双峰特征,固化铅污染土中铅形成Si-O-Pb结合体、PbAl2O4、CaPbO3等沉淀是铅固化稳定化的主要机理之一。 相似文献
95.
An efficient red phosphorescent organic light emitting diode (PhOLED) has been realized by utilizing a composite hole transporting layer comprised of all-inorganic cesium lead halide perovskite CsPbBr3 via spin-coating and 1,3-bis(9-carbazolyl) benzene (mCP) by vacuum depositing, in which CsPbBr3 film is used as a hole transporting layer and mCP plays a dominant role in electron and exciton blocking. And this PhOLED shows a saturated red emission coordinated at CIE (0.65, 0.33) driven at 7.5 V, a maximum brightness of 20,750 cd/m2, and a maximum current efficiency of 10.64 cd/A, which is as 1.87 times as that 5.68 cd/A of the reference PhOLEDs based on traditional small organic molecular hole transporting material N,N′-bis(naphthalen-1-yl)-N,N′-bis(phenyl)-benzi (NPB). The electroluminescent (EL) spectra and the energy level alignment of different PhOLEDs are investigated. The enhanced EL performances are ascribed to improved hole injecting and transporting behaviors, and better electron and exciton confinements by introducing the composite hole transporting layer CsPbBr3/mCP. 相似文献
96.
Structural study of a lead (II) organic complex – a key precursor in a green recovery route for spent lead‐acid battery paste 下载免费PDF全文
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This work proposes a novel design method for generalized order lead/lag compensators. With respect to the traditional lead/lag compensator, it introduces a new parameter, β, which is a non-integer number. A new design method of the compensator is introduced in order to quantify its design parameters. Compared to its integer order counterpart, the generalized order lead compensator facilitates with the unique solution of desired design specifications with maximum phase at the desired gain cross-over frequency to achieve reshaping of the loop frequency domain characteristics. On the other hand, generalized order lag compensator is designed so as to allow minimum phase lag at the new gain crossover frequency. Examples with simulation and real-time results are presented to validate the efficacy of the proposed approach. 相似文献
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