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41.
42.
苏里格气田是中国典型的致密砂岩气藏,构造简单、平缓,横向非均质性强,有效储层与围岩声学特征差别小,地震响应不明显,常规地震监测方法预测难度大,但气田含气砂岩泊松比低,是地震气藏检测的有效参数。利用弹性全波形反演精度高和能处理复杂非均质介质的优势,反演地层拉梅常数、剪切模量和密度,并计算泊松比,从而进行气藏预测。重点阐述了苏里格气田多分量数据全波形反演初始模型建模、先验模型建模和地震数据预处理3个关键问题的处理方法。二维三分量数据反演和"甜点"预测结果表明:①对于具有强非均质性的苏里格气田,利用全波形反演获得精度较高的地层弹性参数能显著提高气藏预测的准确度;②苏里格地区构造简单、平缓,利用常规叠加速度并结合构造解释可以建立比较好的初始模型,从而有效地解决了周波跳跃和局部极小的难题;③先验知识的约束和地震数据的预处理是全波形反演成功应用于苏里格气田气藏检测的关键。 相似文献
43.
铝灰是铝工业生产过程中产生的有害固体废物,每年的产生量达到上百万吨。铝灰的大量堆积会引起严重的环境与公共安全问题。铝灰中含有较多的金属铝及其氧化物、氮化物,综合回收利用铝灰对减少环境压力、提升铝行业的经济效益具有重要意义。阐述了铝灰的火法和湿法处理工艺,通过比较得出无盐火法工艺和湿法工艺是值得开发的工艺。介绍了铝灰在耐火材料、陶瓷产品、氢气制备以及工程材料等领域的综合利用现状及研究进展。指出在进一步巩固和发展铝灰原有的高附加值资源化利用的同时,应加强对铝灰处理过程中产生的气体的利用。建议根据铝灰的特性进一步开发新的资源化利用方向。 相似文献
44.
Zhuo Shi Ningning Dong Dingfeng Zhang Xiaofang Jiang Guanxin Du Shichao Lv Jiejie Chen Jun Wang Shifeng Zhou 《Journal of the American Ceramic Society》2019,102(7):3965-3971
The construction of nonlinear optical materials featuring asymmetric transmission of light is of great technological importance for various applications, including optical switching and optical power limiting. A significant challenge is the scalable fabrication of material candidates with good photochemical stability, high optical transmittance, and excellent optical limiting performance. Here, we present a nanocrystallization avenue for constructing hybrid optical limiting materials that exhibit ultrafast and robust optical limiting performance. The experimental results show that the controllable relaxation of a niobate glass may lead to the clustering of Nb-O units and contracting of the bandgap. It results in the notable improvement in nonlinear optical properties, including the enhanced saturation irradiance (380 GW/cm2), doubly increased nonlinear coefficient, and decreased limiting threshold (200 GW/cm2). Our results suggest a promising material that exhibits promising applications for protecting eyes and sensitive components from laser-induced damage. 相似文献
45.
Fei Xu Xiangli Shi Qingzhu Zhang Wenxing Wang 《International journal of molecular sciences》2015,16(8):18714-18731
The chlorothiophenoxy radicals (CTPRs) are key intermediate species in the formation of polychlorinated dibenzothiophenes/thianthrenes (PCDT/TAs). In this work, the formation of CTPRs from the complete series reactions of 19 chlorothiophenol (CTP) congeners with H and OH radicals were investigated theoretically by using the density functional theory (DFT) method. The profiles of the potential energy surface were constructed at the MPWB1K/6-311+G(3df,2p)//MPWB1K/6-31+G(d,p) level. The rate constants were evaluated by the canonical variational transition-state (CVT) theory with the small curvature tunneling (SCT) contribution at 600–1200 K. The present study indicates that the structural parameters, thermal data, and rate constants as well as the formation potential of CTPRs from CTPs are strongly dominated by the chlorine substitution at the ortho-position of CTPs. Comparison with the study of formation of chlorophenoxy radicals (CPRs) from chlorophenols (CPs) clearly shows that the thiophenoxyl-hydrogen abstraction from CTPs by H is more efficient than the phenoxyl-hydrogen abstraction from CPs by H, whereas the thiophenoxyl-hydrogen abstraction from CTPs by OH is less impactful than the phenoxyl-hydrogen abstraction from CPs by OH. Reactions of CTPs with H can occur more readily than that of CTPs with OH, which is opposite to the reactivity comparison of CPs with H and OH. 相似文献
46.
Yanlong Shi Xiaojuan Feng Haiyu Guan Jiahua Zhang Zhongai Hu 《International Journal of Hydrogen Energy》2021,46(12):8557-8566
Constructing high-efficient and nonprecious electrocatalysts is of primary importance for improving the efficiency of water splitting. Herein, a novel sunflower plate-like NiFe2O4/CoNi–S nanosheet heterostructure was fabricated via facile hydrothermal and electrodeposition methods. The as-fabricated NiFe2O4/CoNi–S heterostructure array exhibits remarkable bifunctional catalytic activity and stability toward oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) in alkaline media. It presents a small overpotential of 219 mV and 149 mV for OER and HER, respectively, to produce a current density of 10 mA cm?2. More significantly, when the obtained electrodes are used as both the cathode and anode in an electrolyzer, a voltage of 1.57 V is gained at 10 mA cm?2, with superior stability for 72 h. Such outstanding properties are ascribed to: the 3D porous network structure, which exposes more active sites and accelerates mass transfer and gas bubble emission; the high conductivity of CoNi–S, which provides faster charge transport and thus promotes the electrocatalytic reaction of the composites; and the effective interface engineering between NiFe2O4 (excellent performance for OER) and CoNi–S (high activity for HER), which leads to a shorter transport pathway and thus expedites electron transfer. This work provides a new strategy for designing efficient and inexpensive electrocatalysts for water splitting. 相似文献
47.
汾西矿务局水峪矿部分工作面现已面临带压开采问题,受下伏奥陶系灰岩水害影响,工作面安全回采过程中的防治水工作难度增加,尤其是带压开采工作面底板灰岩水的有效探测变得异常紧迫与重要。为了解决底板带压开采工作面富水区的探测问题,水峪矿引入了并行电透视技术,并对相应工作面进行了探测应用。并行电透视技术相对于传统音频电透视技术具有仪器智能化控制发射接收切换、一发射点并行对应多接收点、仪器智能快速高效跑极施工的3项技术优势,可体现应用现场施工高效、实际探测效果可靠的技术特点。经过对并行电透视技术及探测应用效果分析研究,证明该方法技术领先,现场施工高效,实际探测结果可靠,实用性强。 相似文献
48.
49.
Xueli Du Yuelong Wang Rongna Shi Zhiyong Mao Zhihao Yuan 《Journal of the European Ceramic Society》2018,38(10):3512-3517
The PbClxS1-x and Pb1-xBixS (x? =?0–0.05) bulks were fabricated with a facile method of hydrothermal synthesis and microwave sintering, and the effect of anionic and cationic donors on the thermoelectric performance of PbS was investigated. Although Cl? and Bi3+ both effectively improved the thermoelectric properties of n-type PbS, more excellent thermoelectric performance was obtained from Cl? doped samples because of higher electrical property and lower thermal conductivity at higher temperature (T? >?600?K). The thermoelectric figure of merit (ZT) reaches 1.04 for PbCl0.015S0.985 at 800?K and increases with temperature increasing without sign of saturation, which is probably the highest value ever reported for single-phase polycrystalline n-type PbS. The results also indicate that the hydrothermal synthesis and microwave sintering can realize anion doping as well as cation doping for n-type PbS at low cost, and PbS should be a robust alternative for PbTe thermoelectric materials. 相似文献