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高炉炼铁炉料中硫的迁移规律

钢铁 2024年第4期59卷 34-41页

作者：华建明郑壮游洋吕学伟宝钢股份炼铁厂上海200941 重庆大学材料科学与工程学院重庆400044

钢铁行业的二氧化硫排放量占全国工业总排放量的13.9%,而高炉炼铁过程是钢铁生产中硫排放的重要环节。随着环保要求的日益严格,降低高炉煤气中硫化物的含量显得尤为重要。为了探明高炉冶炼过程炉料中硫化物的演变机理,采用化学分析和XP... 详细信息

钢铁行业的二氧化硫排放量占全国工业总排放量的13.9%,而高炉炼铁过程是钢铁生产中硫排放的重要环节。随着环保要求的日益严格,降低高炉煤气中硫化物的含量显得尤为重要。为了探明高炉冶炼过程炉料中硫化物的演变机理,采用化学分析和XPS方法对高炉炉料中硫的赋存形态及含量进行表征,计算得到高炉硫负荷;并采用热力学平衡计算方法对高炉不同区域硫在渣-金-气三相的分配机制进行研究。结果表明,高炉原料中硫的最大来源为焦炭,占全部硫收入的72.3%,其次煤粉占19.7%,而含铁原料(烧结矿、球团矿和块矿)合计硫质量分数小于10%。焦炭和煤粉中的硫主要以砜类硫、亚砜类硫、噻吩类硫等有机硫和硫化物硫、硫酸盐硫等无机硫形式存在,且焦炭中硫含量高于煤粉。高炉块状带煤气中硫的来源主要是炉料中无机硫的热解、炉料与还原性气氛反应生成的气态H_(2)S和COS,以及软熔带以下区域反应产生的气态硫化物经过炉料吸收后剩余的COS。此外,高炉煤气中COS含量通常高于H_(2)S。高炉软熔带炉料具有良好的吸硫条件,硫主要存在于刚形成的初渣中。炉缸区域硫元素主要存在于炉渣中,其次为铁水,最后才是煤气。随着温度的升高,炉渣的脱硫能力提高,更多的硫从铁水向渣中转移。

关键词：高炉硫化物演变机理热力学计算硫平衡

Effects of process parameters on the growth behavior and granule size distribution of iron ore mixtures in a novel high-shear granulator

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International Journal of Minerals,Metallurgy and Materials 2022年第12期29卷 2152-2161页

作者： Yang You Jiabao Guo Gang Li zhuang zheng Yong Li Xuewei Lü College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium–Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China

This work proposes a novel horizontal high-shear granulator for iron ore granulation before sintering *** granulation behavior such as growth process and structure of granules were firstly analyzed,followed by the effects of operation conditions such as water content,initial particle size distribution,and the concentrate *** results show that the granule size increased significantly with increasing the granulation time,and the structure of granule can be divided into three types:non-nuclei,single-nuclei,and *** promotes the coalescence and growth of particles,and a better granulation performance was obtained at the water content of 8.8wt%under the current raw material *** the nuclei particle ratio led to an increase in average size of granules and permeability of the granules bed,but a decrease in growth ***,with increasing of concentrate ratio,granulation performance such as granule size,bed permeability,and uniformity became worse.

关键词： horizontal high-shear granulation iron ore granule structure granulation performance size distribution

基于VMD方法的混凝土缺陷超声成像噪声处理研究

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计算机测量与控制 2024年第3期32卷 247-252页

作者：庄政任宏伟田博文郑元成路乾济南大学自动化与电气工程学院济南250024

时间反演多信号分类(TR-MUSIC)算法进行混凝土结构缺陷超声成像,能够在激励超声频率不改变,保证探测深度的情况下,打破衍射限制,实现超分辨率成像;但此方法的缺点是极易受到噪声的干扰,在成像划分信号子空间与噪声子空间过程,产生附加... 详细信息

时间反演多信号分类(TR-MUSIC)算法进行混凝土结构缺陷超声成像,能够在激励超声频率不改变,保证探测深度的情况下,打破衍射限制,实现超分辨率成像;但此方法的缺点是极易受到噪声的干扰,在成像划分信号子空间与噪声子空间过程,产生附加奇异值,影响超声成像的精度和准确性;为进一步提高TR-MUSIC超声成像的质量和稳定性,抑制噪声对成像的干扰,提出一种基于变模态分解(VMD)的噪声处理方式,该方法首先对VMD分解后的变模态分量采用能量熵和重心熵结合的方式来确定信号频谱形态发散和能量分布不均的噪声分量,对噪声分量采用小波阈值降噪方法处理,然后将降噪后的噪声分量和其他分量进行最小二乘平滑滤波并重构;改善后的信号进行反演成像,提高了信号子空间和噪声子空间对应奇异值大小的区分度,再通过设定阈值方式进行划分,提高了成像分辨率,抑制了由噪声引起的伪像问题。

关键词：超声成像变模态分解混凝土降噪奇异值重心熵能量熵

Investigation on the granulation behavior of iron ore fine in a horizontal high-shear granulator

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Particuology 2022年第9期20卷 57-64页

作者： Yang You Jiabao Guo Gang Li zhuang zheng Yong Li Yaowei Yu Xuewei Lv College of Materials Science and Engineering Chongqing UniversityChongqing 400044China Chongqing Key Laboratory of Vanadium-Titanium Metallurgy and New Materials Chongqing UniversityChongqing 400044China State Key Laboratory of Advanced Special Steel Shanghai Key Laboratory of Advanced FerrometallurgySchool of Materials Science and EngineeringShanghai UniversityShanghai 200444China State Key Laboratory of Mechanical Transmissions Chongqing UniversityChongqing 400044China

High-shear granulation is widely used in many particulate industries for its good capability to improve the size,strength and composition uniformity of powder *** work conducted an experimental study to investigate the granulation behavior of iron ore fine in a horizontal high-shear granulator,such as granules size distribution,granules growth rate,and permeability of the granules *** results show that the granule size and permeability of packed granules bed increase gradually with increasing the granulation time,and the growth of granules can be divided into three stages:the rapid growth stage,the slow growth stage and the relatively stable *** the higher rotational speed and larger number of impellers increase the kinetic energy and collision frequency of the particles,which causes the increase of average granule size,growth rate and permeability of granules packed *** the other hand,the shear damage effect of the impellers on the granules is also enhanced with the increase of rotational speed and impeller number,resulting in significant granule size segregation.

关键词： High shear granulation Iron ore Particle Size distribution

Effects of acupuncture on hypothalamic–pituitary–adrenal axis:Current status and future perspectives

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Journal of Integrative Medicine 2024年第4期22卷 445-458页

作者： Jia-yuan zheng Jing Zhu Yu Wang Zhan-zhuang Tian Department of Integrative Medicine and Neurobiology School of Basic Medical SciencesState Key Laboratory of Medical Neurobiology and Ministry of Education Frontiers Center for Brain ScienceInstitutes of Brain ScienceInstitute of Acupuncture ResearchAcademy of Integrative MedicineShanghai Key Laboratory for Acupuncture Mechanism and Acupoint FunctionShanghai Medical CollegeFudan UniversityShanghai 200032China Department of Human Anatomy School of Integrative MedicineShanghai University of Traditional Chinese MedicineShanghai 201203China

The hypothalamic–pituitary–adrenal(HPA) axis is a critical component of the neuroendocrine system,playing a central role in regulating the body's stress response and modulating various physiological processes. Dysregulation of HPA axis function disrupts the neuroendocrine equilibrium, resulting in impaired physiological functions. Acupuncture is recognized as a non-pharmacological type of therapy which has been confirmed to play an important role in modulating the HPA axis and thus favorably targets diseases with abnormal activation of the HPA axis. With numerous studies reporting the promising efficacy of acupuncture for neuroendocrine disorders, a comprehensive review in terms of the underlying molecular mechanism for acupuncture, especially in regulating the HPA axis, is currently in need. This review fills the need and summarizes recent breakthroughs, from the basic principles and the pathological changes of HPA axis dysfunction, to the molecular mechanisms by which acupuncture regulates the HPA axis. These mechanisms include the modulation of multiple neurotransmitters and their receptors, neuropeptides and their receptors, and microRNAs in the paraventricular nucleus,hippocampus, amygdala and pituitary gland, which alleviate the hyperfunctioning of the HPA *** review comprehensively summarizes the mechanism of acupuncture in regulating HPA axis dysfunction for the first time, providing new targets and prospects for further exploration of acupuncture.

关键词： Acupuncture Electroacupuncture Hypothalamic-pituitary-adrenal axis Mechanism Neurotransmitter microRNA

Enhancement of liquid-liquid micromixing performance in curved capillary microreactor by generation of Dean vortices

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Chinese Journal of Chemical Engineering 2024年第4期68卷 76-82页

作者： Shaoyun Wu zhuang Ma Zichi Yang Suying Zhao Caijin Zhou Huidong zheng Fujian Engineering Research Center of Advanced Manufacturing Technology for Fine Chemicals College of Chemical EngineeringFuzhou UniversityFuzhou 350108China Qingyuan Innovation Laboratory Quanzhou362114China

Micromixing efficiency is an important parameter for evaluating the multiphase mass transfer performance and reaction efficiency of *** this work,the novel curved capillary reactor with different shapes was designed to generate Dean flow,which was used to enhance the liquid-liquid micromixing *** Villermaux-Dushman probe reaction was employed to characterize the micromixing performance in different curved capillary *** effects of experiment parameters such as liquid flow rate,inner diameter,tube length,and curve diameter on micromixing performance were systematically *** the optimal conditions,the minimum value of the segmentation factor XS was *** was worth noting that at the low Reynolds number(Re<30),the change of curved shape on the capillary microreactor can significantly improve the micromixing performance with XS reduced by 37.5%.Further,the correlations of segment index XS with dimensionless factor such as Reynolds number or Dean number were developed,which can be used to predict the liquid-liquid micromixing performance in capillary microreactors.

关键词： Microreactor Process intensification Micromixing performance Dean flow

GS-orthogonalization OMP method for space target detection via bistatic space-based radar

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Chinese Journal of Aeronautics 2024年第7期37卷 333-351页

作者： Shuyu zheng Libing JIANG Qingwei YANG Yingjian ZHAO zhuang WANG National Key Laboratory of Science and Technology on Automatic Target Recognition College of Electronic Science and TechnologyNational University of Defense TechnologyChangsha 410073China

A space-based bistatic radar system composed of two space-based radars as the transmitter and the receiver respectively has a wider surveillance region and a better early warning capability for high-speed targets,and it can detect focused space targets more flexibly than the monostatic radar system or the ground-based radar ***,the target echo signal is more difficult to process due to the high-speed motion of both space-based radars and space *** be specific,it will encounter the problems of Range Cell Migration(RCM)and Doppler Frequency Migration(DFM),which degrade the long-time coherent integration performance for target detection and localization *** solve this problem,a novel target detection method based on an improved Gram Schmidt(GS)-orthogonalization Orthogonal Matching Pursuit(OMP)algorithm is proposed in this ***,the echo model for bistatic space-based radar is constructed and the conditions for RCM and DFM are ***,the proposed GS-orthogonalization OMP method is applied to estimate the equivalent motion parameters of space ***,the RCM and DFM are corrected by the compensation function correlated with the estimated motion ***,coherent integration can be achieved by performing the Fast Fourier Transform(FFT)operation along the slow time direction on compensated echo *** simulations and real raw data results validate that the proposed GS-orthogonalization OMP algorithm achieves better motion parameter estimation performance and higher detection probability for space targets detection.

关键词： Bistatic space-based radar High-speed maneuvering space targets detection Range Cell Migration(RCM) Doppler Frequency Migration(DFM) Gram Schmidt(GS)-orthogonalization Orthogonal Matching Pursuit(OMP)algorithm

Analysis of RNA Recognition and Binding Characteristics of OsCPPR1 Protein in Rice

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Rice science 2024年第2期31卷 215-225,I0032-I0035页

作者： zheng Shaoyan CHEN Junyu LI Huatian LIU Zhenlan LI Jing zhuang Chuxiong State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources/Guangdong Laboratory for Lingnan Modern Agriculture/College of Life Sciences South China Agricultural UniversityGuangzhou 510642China

Pentatricopeptide repeat(PPR)proteins represent one of the largest protein families in plants and typically localize to organelles like mitochondria and *** contrast,CYTOPLASMLOCALIZED PPR1(OsCPPR1)is a cytoplasm-localized PPR protein that can degrade OsGOLDENLIKE1(OsGLK1)mRNA in the tapetum of rice ***,the mechanism,by which OsCPPR1 recognizes and binds to OsGLK1 transcripts,remains *** protein structure prediction and macromolecular docking experiments,we observed that distinct PPR motif structures of OsCPPR1 exhibited varying binding efficiencies to OsGLK1 ***,RNA-electrophoretic mobility shift assay experiment demonstrated that the recombinant OsCPPR1 can directly recognize and bind to OsGLK1 mRNA in *** further confirmed that the mutations in the conserved amino acids in each PPR motif resulted in loss of activity,while truncation of OsCPPR1 decreased its binding *** findings collectively suggest that it may require some co-factors to assist in cleavage,a facet that warrants further exploration in subsequent studies.

关键词： OsCPPR1 RNA recognition and binding pentatricopeptide repeat rice

Mitochondrial dysfunction and quality control lie at the heart of subarachnoid hemorrhage

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Neural Regeneration Research 2024年第4期19卷 825-832页

作者： Jiatong Zhang Qi Zhu Jie Wang zheng Peng Zong zhuang Chunhua Hang Wei Li Department of Neurosurgery Nanjing Drum Tower HospitalAffiliated Hospital of Medical SchoolNanjing University Department of Neurosurgery Nanjing Drum Tower HospitalClinical College of Nanjing Medical University

The dramatic increase in intracranial pressure after subarachnoid hemorrhage leads to a decrease in cerebral perfusion pressure and a reduction in cerebral blood *** are directly affected by direct factors such as ischemia,hypoxia,excitotoxicity,and toxicity of free hemoglobin and its degradation products,which trigger mitochondrial *** mitochondria release large amounts of reactive oxygen species,inflammatory mediators,and apoptotic proteins that activate apoptotic pathways,further damaging *** response to this array of damage,cells have adopted multiple mitochondrial quality control mechanisms through evolution,including mitochondrial protein quality control,mitochondrial dynamics,mitophagy,mitochondrial biogenesis,and intercellular mitochondrial transfer,to maintain mitochondrial homeostasis under pathological *** interventions targeting mitochondrial quality control mechanisms have emerged as promising therapeutic strategies for subarachnoid *** review provides an overview of recent research advances in mitochondrial pathophysiological processes after subarachnoid hemorrhage,particularly mitochondrial quality control *** also presents potential therapeutic strategies to target mitochondrial quality control in subarachnoid hemorrhage.

关键词： mitochondrial biogenesis mitochondrial dynamics mitochondrial dysfunction mitochondrial fission and fusion mitochondrial quality control mitophagy subarachnoid hemorrhage