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magnesium-containing pellet regulating blast furnace ferrous burden interaction:softening-melting behavior and mechanism

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Journal of Iron and Steel Research International 2024年第7期31卷 1623-1635页

作者： Li-ming ma jian-liang Zhang Yao-zu Wang Xiao-yong ma Gui-lin Wang Zhuo Li Hui-qing jiang Zheng-jian Liu School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Intelligence Science and Technology University of Science and Technology BeijingBeijing 100083China Lingyuan Iron and Steel Group Co. Lingyuan 122500LiaoningChina

MgO participates in all stages of sintering,pelletizing,and blast furnace ironmaking,and synergistically optimizing the distribution of MgO in ferrous burden can effectively enhance the interaction within the ferrous burdens and optimize the softening-melting properties of the mixed ***-containing pellets mixed with low-MgO sinter or mixed with high-MgO sinter in the blast furnace ferrous burden structure have opposite softening-melting performance *** the structure of the ferrous burden is magnesium-containing pellets mixed with low-MgO sinter,the magnesium-containing pellets can enhance the interaction of the ferrous burden in the process of softening-melting,which can optimize the composition of the slag phase and improve the slag *** the structure of the ferrous burden is magnesium-containing pellets mixed with high-MgO sinter,the magnesium-containing pellets weaken the interaction of the ferrous burden in the process of softening-melting,increase the content of the high melting point solid-phase particles in the slag,lead to an increase in the viscosity of the slag and difficult separation of the slag and iron,and decrease the permeability of the charge ***,to ensure good permeability of the mixed burden,the following measures are suggested:optimizing the MgO distribution of the ferrous burden,reducing the MgO content of the sinter to 1.96 wt.%,increasing the MgO content of the pellets to 1.03-1.30 wt.%,controlling the MgO/Al_(2)O_(3) ratio of the mixed burden within 1.15-1.32,narrowing the position of the cohesive zone,and maintaining an S value(permeability index)of approximately 150 kPa℃.

关键词： Ironmaking Ferrous burden Softening-melting property Interaction Permeability Slag

Preliminary techno-economic analysis of three typical decentralized composting technologies treating rural kitchen waste:a case study in China

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Frontiers of Environmental Science & Engineering 2023年第4期17卷 97-108页

作者： Haoshu Wang yong Qin Liqing Xin Changxun Zhao Zhuang ma jian Hu Weixiang Wu Institute of Environment Science and Technology College of Environmental and Resource SciencesZhejiang UniversityHangzhou 310058China Zhejiang Province Key Laboratory for Water Pollution Control and Environmental Safety Technology Hangzhou 310058China Zhejiang Transper Environmental Protection Technology Co. Ltd.Hangzhou 310058China

This study was designed to evaluate whether the decentralized rural kitchen waste(KW)composting technologies used in China can be widely *** this end,we completed a techno-economic analysis of three typical types of KW compositing,namely solar-assisted(SAC),bio-enhanced(BEC),and heat-dewatering composting(HDC).These evaluations revealed that all three technologies produce composting products that meet China’s organic fertilizer standard and that both SAC and BEC are economically self-sustaining and generate net profits(18824.94 and 17791.52 US$/a)and positive net present values(32133.11 and 25035.93 US$).Subsequent sensitivity analysis demonstrated that the KW-handling subsidy plays a critical role in making decentralized composting economically *** on these analyses,we believe that reducing the coverage area of SAC,reducing the operating cost of BEC and HDC,upgrading composting products,and strengthening secondary pollution control would aid in supporting the technological improvement of these ***,providing appropriate subsidies and promulgating specific standards and policies for KW fertilizer are key strategies for decentralized rural KW composting management.

关键词： Techno-economic analysis Sensitivity analysis Rural kitchen waste Decentralized composting Organic fertilizer

Experimental investigation of wall-bounded turbulence drag reduction by active control of double piezoelectric vibrator

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Journal of Hydrodynamics 2020年第4期32卷 747-757页

作者： jian-xia Bai yong-xiang Huang Nan jiang Xing-yu ma Zhan-qi Tang Department of Mechanics School of Mechanical EngineeringTianjin UniversityTianjin 300354China Department of mathematics Tianjin University Renai CollegeTianjin 301636China State Key Laboratory of marine Environmental Science College of Ocean and Earth SciencesXiamen UniversityXiamen 361102China Tianjin Key Laboratory of Modern Engineering Mechanics Tianjin 300354China

In order to manipulate the large-scale coherent structures in the wall-bounded turbulence and reduce the skin-friction,an active-control experimental investigation is performed by using the synchronous and asynchronous vibrations of double piezoelectric vibrators embedded spanwisely on a smooth flat plate surface.A TSI-IFA300 hot-wire anemometer and a TSI-1621 A-Tl.5 hot-wire probe are used to measure the time series of the instantaneous velocity at different *** influences of the vibrations on the wall-bounded turbulence are compared in a multi-scale point of view.A disturbance Reynolds Number Red=pd2 f/μis introduced to represent the disturbance.A probability density functions(PDFs)of the multi-scale components of the turbulence velocity and the multi-scale conditional phase-averaged waveform are studied in detail using the wavelet *** results show that the maximum drag reduction rate 18.54%is obtained at 100 V/160 Hz and Red=0.54 in the asynchronous vibration *** disturbances generated by the vibrators have a significant influence on the sweep events of the *** asynchronous vibration model is more effective than the synchronous vibration one.A possible physical mechanism is suggested to explain why the disturbance frequency of 160 Hz leads to an optimal parameter set for the drag reduction.

关键词： Wall-bounded turbulence active control drag reduction piezoelectric vibrator multi-scale analysis conditional phase-averaged wavefonns coherent structure

Glass-forming ability and corrosion performance of Mn-doped Mg-Zn-Ca amorphous alloys for biomedical applications

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Rare Metals 2018年第7期37卷 579-586页

作者： jian-Li Wang Yin Wan Zhi-Jun ma yong-Chun Guo Zhong Yang Ping Wang jian-Ping Li School of materials and Chemical Engineering Xi'an Technological University

In the present work, ribbon and 2-mm rod samples of Mg-Zn-Ca-Mn alloys were prepared by meltspinning and copper mold injection methods, respectively. Effects of Mn doping on glass-forming ability and corrosion performance in simulated body fluid of Mg65Zn30Ca5 alloy were studied through X-ray diffraction, scanning electron microscopy, differential scanning calorimeter, and electrochemical and immersion tests. Results show that with the Mn addition increasing, all the ribbon samples are completely in amorphous state. However, the microstructure of 2-mm rod samples transfers from fully amorphous for the Mn-free alloy to almost polycrystalline state with precipitated Mg, Mn, and MgZn phases. Glass-forming ability of Mg65Zn30Ca5 alloy is decreased by Mn addition. Results of electrochemical and immersion tests demon- strate that the Mn-doped samples exhibit more negative corrosion potential and larger corrosion current density, suggesting that the corrosion resistance decreases with doping amount of Mn element increasing.

关键词： Mg-Zn-Ca amorphous alloys Mn doping Glass-forming ability Corrosion performance

Modal Parameter Identification Method of Jacket Platform Structure Based on AFDD and Optimized FBFFT

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China Ocean Engineering 2023年第3期37卷 393-407页

作者： LENG jian-cheng ma Jin-yong FAN Zong-heng QIAN Wan-dong FENG Hui-yu School of Mechanical Science and Engineering Northeast Petroleum UniversityDaqing 163318China

Offshore platforms are susceptible to structural damage due to prolonged exposure to random loads,such as wind,waves,and *** is particularly true for platforms that have been in service for an extended *** the modal parameters of offshore platforms is crucial for damage diagno sis,as it serves as a prerequisite and foundation for the ***,it holds great significance to prioritize the identification of these *** at the shortcomings of the traditional Fast Bayesian Fast Fourier Transform(FBFFT) method,this paper proposes a modal parameter identification method based on Automatic Frequency Domain Decomposition(AFDD) and optimized *** introducing the AFDD method and Powell optimization algorithm,this method can automatically identify the initial value of natural frequency and solve the objective function efficiently and *** order to verify the feasibility and effectiveness of the proposed method,it is used to identify the modal parameters of the IASC-ASCE benchmark model and the j acket platform structure model,and the Most Probable Value(MPV) of the modal parameters and their respective posterior uncertainties are successfully *** identification results of the IASC-ASCE benc hmark model are compared with the identification re sults of the MODE-ID method,which verifies the effectivene ss and accuracy of the proposed method for identifying modal *** provides a simple and feasible method for quantifying the influence of uncertain factors such as environmental parameters on the identification results,and also provide s a reference for modal parameter identification of other large structures.

关键词： jacket platform uncertain modal parameter identification FBFFT method environmental excitation AFDD method Powell optimization

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微量荧光法在苯丙酮尿症诊治中的应用

实用医技杂志 2002年第4期9卷 245-247页

作者：简永建马英杰马志军胡锦春李艳霞卢丽红北京市儿童保健所北京100045

目的 :探讨微量荧光法定量苯丙氨酸在苯丙酮尿症 (PKU)诊治中的应用。方法 :对芬兰 L absystem s公司生产的新生儿苯丙氨酸定量试剂盒及设备进行方法学鉴定 ,并测定 194 7例新生儿和 2 8例经典苯丙酮尿症患儿及 8例持续性高苯丙氨酸血... 详细信息

目的 :探讨微量荧光法定量苯丙氨酸在苯丙酮尿症 (PKU)诊治中的应用。方法 :对芬兰 L absystem s公司生产的新生儿苯丙氨酸定量试剂盒及设备进行方法学鉴定 ,并测定 194 7例新生儿和 2 8例经典苯丙酮尿症患儿及 8例持续性高苯丙氨酸血症患儿末梢血中苯丙氨酸 (Phe)水平观察其实用性。结果 :经实验方法学鉴定 ,本法高、中、低各浓度批内平均变异系数 (CV)为0 .0 36 ,0 .0 6 9,0 .0 6 8,批间平均变异系数 (CV)为 0 .12 4 ;最低检测极限为 31μmol/ L ;平均重现率为 98.4 %。新生儿血苯丙氨酸水平正常参考范围 :31～ 12 0 μmol/ L。 2 8例经典苯丙酮尿症和 8例持续性高苯丙氨酸血症患儿血苯丙氨酸平均含量分别为 186 7μmol/ L(s=4 0 9.8)和 76 9μmol/ L(s=2 2 6 .2 ) ,三者间有显著性差异 P<0 .0 0 1。患儿治疗前后苯丙氨酸平均含量有明显差异 P<0 .0 0 1。结论 :微量荧光法定量准确操作简便适于

关键词：微量荧光法苯丙酮尿症 PKU 苯丙氨酸 Phe 论断治疗儿童血

Parameter estimation for rigid body after micro-Doppler removal based on L-statistics in the radar analysis

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Journal of Systems Engineering and Electronics 2015年第3期26卷 457-467页

作者： yong Wang jian Kang School of Electronics and Information Engineering Harbin Institute of Technology

In traditional inverse synthetic aperture radar （ISAR） imaging of moving targets with rotational parts, the micro-Doppler （m-D） effects caused by the rotational parts influence the quality of the radar images. Recently, L. Stankovic proposed an m-D removal method based on L-statistics, which has been proved effective and simple. The algorithm can extract the m-D effects according to different behaviors of signals induced by rotational parts and rigid bodies in time-frequency （T-F） domain. However, by removing m-D effects, some useful short time Fourier transform （STFT） samples of rigid bodies are also extracted, which induces the side lobe problem of rigid bodies. A parameter estimation method for rigid bodies after m-D removal is proposed, which can accurately re- cover rigid bodies and avoid the side lobe problem by only using m-D removal. Simulations are given to validate the effectiveness of the proposed method.

关键词： parameter estimation L-statistics micro-Doppler (m-D) radar imaging.

Theoretical studies of insertion reactions of singlet germylene into aryl C-C1 bond of 1-chlorobenzene

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Chinese Chemical Letters 2009年第3期20卷 374-377页

作者： Chuan Lu Wan yong ma Yu Zhen Fang jian Hua Zhou School of Chemical Engineering Shandong Institute of Light Industry Jinan 250353 China

The insertion reactions of germylene into C-Cl bond of 1-chorobenzene have been explored using density functional theory. Five germylene species have been chosen for systematically studying. All the stationary points were determined at the B3LYP/ 6-311＋G （d, p） level of the theory. The results show that, the smaller the AEsT of germylene, the lower the barrier height, and the electropositive substituents on the germylene can increase the reaction activity and exothermicity of insertion into C-Cl bond of 1- chorobenzene.

关键词： Germylene Insertion reactions Density functional theory 1-Chorobenzene

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Chinese Journal of Chemical Physics 2009年第1期22卷 13-18页

作者： jian Li Yan-qing Ni yong-qing Li Wei-li Wang Feng-cai ma Department of Science Shenyang Institute of Aeronautical Engineering Shenyang 110036 China Department of Physics Liaoning University Shenyang 110036 China Department of chemistry University of Coimbra 3004-535 Coimbra Portugal School of Science Liaoning Technical University Fuxin 123000 China

To study theoretically the relationship between the integral interference angle and the scat- tering angle in collisional quantum interference, the integral interference angle of atom- ^2П[case（a）] diatomic molecules system is described. To simulate the experiment theoretically, the theoretical model on collision-induced rotational energy transfer in an atom- ^2П[case（a）]diatom system is presented based on the first order Born approximation taking into account of the long-range interaction potential. For the ^2П electronic state in the Hund＇s case（a） diatom, the degree of the interference is discussed. The interference angles of collision-induced rotational energy transfer of CN（A^2П） in Hund＇s case（a） with He, Ne, and Ar are calculated quantitatively. The key parameters in the determination of integral interference angles are obtained.

关键词： Collisional quantum interference Rotational energy transfer Interference angle