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Preparation of hydro-sodalite from fly ash using a hydrothermal method with a submolten salt system and study of the phase transition process

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International Journal of Minerals,Metallurgy and Materials 2020年第1期27卷 55-62页

作者： Yan-bing Zong Cheng-yu Zhao Wen-hui Chen Zhao-bo Liu Da-qiang Cang School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China China Nonferrous Engineering and Research Institute(China ENFI Engineering corporation) Beijing 100038China

Hydro-sodalites are zeolitic materials with a wide variety of *** ash is an abundant industrial solid waste,rich in silicon and aluminum,from which hydro-sodalite can be ***,traditional hydrothermal synthesis methods are complex and cannot produce high-purity ***,there is a demand for processing routes to obtain high-purity *** the present study,high-purity hydro-sodalite(90.2 wt%)was prepared from fly ash by applying a hydrothermal method to a submolten salt *** were characterized by powder X-ray diffraction(XRD),scanning electron microscopy(SEM),thermogravimetry and differential thermal analysis(TG–DTA),and Fourier transform infrared spectroscopy(FTIR)to confirm and quantify conversion of the raw material into the product *** of the samples prepared with an H2O/Na OH mass ratio of 1.5 and an H2O/fly ash mass ratio of 10 was calculated and the conversion process of the product phase was *** of the product was influenced more by the Na OH concentration,less by the H2O/fly ash mass *** main reaction process of the system is that the Si O ions produced by dissolution of the vitreous body in the fly ash and Na+ions in the solution reacted on the destroyed mullite skeleton to produce *** processing route could help mitigate processing difficulties,while producing high-purity hydro-sodalite from fly ash.

关键词： fly ash submolten salt system hydrothermal method hydro-sodalite

The deposition of asphaltenes under high-temperature and highpressure (HTHP) conditions

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Petroleum Science 2023年第1期20卷 611-618页

作者： Rui-Ying Xiong Ji-Xiang Guo Wyclif Kiyingi Hai-Xia Xu Xin-Peng Wu Unconventional Petroleum Research Institute China University of PetroleumBeijing102249China Petroleum Engineering Research Institute of Tarim Oilfield China National Petroleum CorporationXinjiang84100China

In this work,the factors affecting asphaltenes deposition in high-temperature and high-pressure wells were studied using backscattered light and PVT equipment customized to suit the well *** an examination of the intensity of backscattered light,it was revealed that there exists a linear relationship between temperature and asphaltene precipitation within a specific temperature *** this range,a decrease in temperature tends to accelerate asphaltene ***,the impacts of pressure and gas-oil ratio are more *** pressure depletion induces the asphaltenes to precipitate out of the solution,followed by the formation of flocs below the bubble *** addition,an increase in the gas-oil ratio causes a more severe asphaltene deposition,shifting the location of asphaltenes to deep well sections.

关键词： HTHP reservoir Asphaltene Aggregation Gas-oil ratio HTHP PVT cell Back-scattered light

Effects of loading transition metal(Mn,Cr,Fe,Cu) oxides on oxygen storage/release properties of CeO2-ZrO2 solid solution

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Journal of Rare Earths 2020年第3期38卷 274-280页

作者： Zhizhe Zhai Dali Cui Yongqi Zhang Yongke Hou Meisheng Cui He Zhang Jianhui Song Hao Wang National Engineering Research Center for Rare Earth Materials GRINM Group Corporation LimitedBeijing 100088China Grirem Advanced Materials Co.Ltd. Beijing 100088China

Cerium zirconium-based(CZ) oxygen storage materials(OSMs) play a crucial role in three-way catalysts(TWCs),while CZ needs to be modified to satisfy more rigorous emission *** this study,transition metal(TMs=Mn,Cr,Fe,Cu) oxides modified CZ were prepared by incipient wetness impregnation method to improve the oxygen storage capacity of CZ-based *** clearly illustrate the influence of TM oxides,N2 adsorption-desorption,X-ray diffraction(XRD),oxygen storage capacity(OSC),temperature programmed reduction by H2(H2-TPR) and X-ray photoelectron spectroscopy(XPS) were used to characterize the physical and chemical properties of *** is found that,all modified CZ have higher OSC,lower reduction temperatures than those of pristine *** between TMOs and CZ take precedence over specific surface to influence ***,FeOx/CZ has the highest OSC,which is about 1.9 times that of CZ and it could be attributed to synergistic effect between FeOx and CZ;CuOx/CZ has the lowest reduction temperature which is 168℃lower than that of CZ,and it can be explained by hydrogen spillover effect.

关键词： Transition metals Ceria-Zirconia Incipient wetness impregnation OSC

A post-synthesis modification method of molecular sieve 13X for enriching hopanoids in petroleum

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Petroleum Research 2021年第3期6卷 257-263页

作者： Yu Fang Ling Huang Yanhua Shuai Bin Zhang Honggang Nie Jin Li Caiyun Wei Huajian Wang Wenlong Zhang Key Laboratory of Petroleum Geochemistry Research Institute of Petroleum Exploration and DevelopmentChina National Petroleum CorporationBeijing100083China College of Chemistry and Molecular Engineering Peking UniversityBeijing100871China Department of Gas Geology Research Institute of Petroleum Exploration and DevelopmentChina National Petroleum CorporationBeijing100083China

In this study,alkali/acid treatment and ion exchange post-synthesis modification methods to modify the pore diameter and structure of molecular sieve 13X(MS13X)were applied to obtain products,which could then be implemented to improve the enrichment recovery of hopanoids in *** modification products were analyzed by SEM with EDS,XRD and nitrogen *** results indicated that the product which had been prepared in the oxalic acid ethanol solution formed some mesopores,and also retained the initial framework of *** was revealed that this product was able to remarkably increase the recovery rate of hopanoids in petroleum without leading to a significant isotope fractionation *** is thus shown that this modification method of non-aqueous oxalic acid solution for MS13X can be used as an effective pretreatment tool in the application of compoundspecific isotope analysis of hopanes with low concentration.

关键词： Molecular sieve Modification Enrich Hopanoids Petroleum

Preparation and Magnetic Properties of Mn-Zn Ferrites by the Co-precipitation Method

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Journal of Wuhan University of Technology(Materials Science) 2009年第6期24卷 875-878页

作者：李雪张俊喜 School of Environmental and Chemical Engineering Shanghai University Electrochemical Research Group Shanghai University of Electric PowerKey Laboratory of State Power Corporation of China

Mn-Zn ferrites （Mn1-xZnxFe2O4） with different compositions were prepared by the coprecipitation method, and the influences of such synthesis conditions as pH value, composition and volume ratio （R） of the mixed solution and NH4HCO3 solution on their microstructures and magnetic properties were discussed. The samples were characterized by X-ray diffraction （XRD） and magnetization measurement instrument. Lattice parameters and average crystalline size of the synthesized materials were calculated from the corresponding XRD patterns with the related software Jade.5. For samples of different pH values, only one phase was found when pH values were 7.0, 8.0 and 9.0. The sample with pH value of 7.0 exhibited the highest saturation magnetic induction, the lowest coercive force, and crystallized best. For samples of different R values with pH value of 7.0, only one phase was observed in all samples, and the sample with R value of 2.3 exhibited the highest saturation magnetic induction and the lowest coercive force. The composition has mainly afected the magnetic properties, and the saturation magnetic induction increases with the increase of the content of Zn （x）, but decreases when x is beyond 0.6. The trend of coercive force is on the contrary. However, no magnetism is exhibited when the x value is up to 0.8.

关键词： co-precipitation method microstructure magnetic property Mn-Zn ferrite

Improved Unit Commitment with Accurate Dynamic Scenarios Clustering Based on Multi-Parametric Programming and Benders Decomposition

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Energy Engineering 2024年第6期121卷 1557-1576页

作者： Zhang Zhi Haiyu Huang Wei Xiong Yijia Zhou Mingyu Yan Shaolian Xia Baofeng Jiang Renbin Su Xichen Tian State Grid corporation of China Beijing100031China Central China Branch State Grid Corporation of ChinaWuhan430077China School of Electric and Electronic Engineering Huazhong University of Science and TechnologyWuhan430074China China Electric Power Research Institute Co. Ltd.Beijing100192China

Stochastic unit commitment is one of the most powerful methods to address uncertainty. However, the existingscenario clustering technique for stochastic unit commitment cannot accurately select representative scenarios,which threatens the robustness of stochastic unit commitment and hinders its application. This paper providesa stochastic unit commitment with dynamic scenario clustering based on multi-parametric programming andBenders decomposition. The stochastic unit commitment is solved via the Benders decomposition, which decouplesthe primal problem into the master problem and two types of subproblems. In the master problem, the committedgenerator is determined, while the feasibility and optimality of generator output are checked in these twosubproblems. Scenarios are dynamically clustered during the subproblem solution process through the multiparametric programming with respect to the solution of the master problem. In other words, multiple scenariosare clustered into several representative scenarios after the subproblem is solved, and the Benders cut obtainedby the representative scenario is generated for the master problem. Different from the conventional stochasticunit commitment, the proposed approach integrates scenario clustering into the Benders decomposition solutionprocess. Such a clustering approach could accurately cluster representative scenarios that have impacts on theunit commitment. The proposed method is tested on a 6-bus system and the modified IEEE 118-bus *** results illustrate the effectiveness of the proposed method in clustering scenarios. Compared withthe conventional clustering method, the proposed method can accurately select representative scenarios whilemitigating computational burden, thus guaranteeing the robustness of unit commitment.

关键词： Stochastic programming unit commitment scenarios clustering Benders decomposition multi-parametric programming

Pharmaceutical salts: Theory, use in solid dosage forms and in situ preparation in an aerosol

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Asian Journal of Pharmaceutical Sciences 2016年第6期11卷 722-734页

作者： Timothy Scott Wiedmanna Amir Naqwib Department of Pharmaceutics University of Minnesota308 Harvard St SEMinneapolisMN 55455USA MSP corporation ShoreviewMN 55126USA

In this article, the theoretical foundation for salts is given with an emphasis on the amount of drug in solution. Consideration is given for the solubility of the non-ionized form, acid dissociation constant and solubility product, which are the limiting constraints. For dissolution of nonionized drugs, the surface pH differs from the bulk pH, giving rise to a lower than expected rate. For salts, theoretical considerations are relatively complex, and an experimental approach to estimating the surface pH is more likely to be of value in predicting the dissolution rate. General guidelines are described for screening, preparing and characterizing drugs as salts, which critically depend on the goal of the product ***, our work involving the preparation of salts as a means to generate aerosols from a solution is provided. The solubility of six structurally related compounds was determined in four acids. Thereafter, the amount of the compound in solution was determined as a function of pH, using the acid that provided the highest solubility. Because the pH required to achieve the needed concentration for aerosol generation was low, ammonia vapor was introduced into the air stream to neutralize aerosol droplets. Solvent was then removed from the aerosol by a silica column. The resulting aerosol had a concentration of 96 μg/l and a mass median particle size of 1.8 μm. The reported pharmacokinetic study substantiated the feasibility of evaluating its safety and efficacy of inhalation administration in the rat model.

关键词： Solubility Salt Aerosol Inhalation Solubility product

Robust flutter analysis based on genetic algorithm

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Science China(Technological Sciences) 2012年第9期55卷 2474-2481页

作者： GU YingSong ZHANG XinPing YANG ZhiChun Institute of Structural Dynamics and Control Northwestern Polytechnical UniversityXi'an 710072China A VIC Shaanxi Aircraft Industry(Group)corporation LTD. Hanzhong 723213China

Robust flutter analysis considering model uncertain parameters is very important in theory and engineering *** robust flutter solution based on structured singular value subject to real parametric uncertainties may become difficult because the discontinuity and increasing complexity in real mu *** is crucial to solve the worst-case flutter speed accurately and efficiently for real parametric *** this paper,robust flutter analysis is formulated as a nonlinear programming *** proper nonlinear programming technique and classical flutter analysis method,the worst-case parametric perturbations and the robust flutter solution will be captured by optimization *** the derived nonlinear programming problem,the parametric uncertainties are taken as design variables bounded with perturbed intervals,while the flutter speed is selected as the objective *** model is optimized by the genetic algorithm with promising global optimum *** present approach avoids calculating purely real mu and makes robust flutter analysis a plain *** is illustrated by a special test case that the robust flutter results coincide well with the exhaustive *** is also demonstrated that the present method can solve the match-point robust flutter solution under constant Mach number accurately and *** method is implemented in problem with more uncertain parameters and asymmetric perturbation interval.

关键词： Flutter genetic algorithm robust flutter analysis match-point solution nonmatch-point solution

Distributed processing based fault location,isolation,and service restoration method for active distribution network

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Journal of Modern Power Systems and Clean Energy 2015年第4期3卷 494-503页

作者： Jiaming WENG Dong LIU Ning LUO Xueyong TANG Electrical Department of Shanghai Jiao Tong University ShanghaiChina Grid Planning&Research Center Guizhou Power Grid CorporationCSGGuiyang 55002China

Active distribution network(ADN)is a solution for power system with interconnection of distributed energy resources(DER),which may change the network operation and power flow of traditional power distribution ***,in some circumstances the malfunction of protection and feeder automation in distribution network occurs due to the uncertain bidirectional power ***,a novel method of fault location,isolation,and service restoration(FLISR)for ADN based on distributed processing is proposed in this *** differential-activated algorithm based on synchronous sampling for feeder fault location and isolation is studied,and a framework of fault restoration is established for ***,the effectiveness of the proposed algorithm is verified via computer simulation of a case study for active distributed power system.

关键词： Active distribution network Fault location isolation and service restoration Distributed processing method