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微震非线性优化定位方法研究与应用

Applied Geophysics 2024年第2期21卷 331-342,420,421页

作者：刘伟建肖扬王浩楠侯梦杰田光辉董森森中原工学院建筑工程学院河南郑州451100 郑州安岩智能科技有限公司河南郑州451100

针对在实际工程应用中,考虑到震动波传播以及各项异性介质等因素的影响,传统线性定位求解过程极易出现发散问题,于是采用数学算法结合微震定位原理,推导得到一种微震非线性优化定位算法;新算法通过引入下山因子,增强了算法的稳定性和收... 详细信息

针对在实际工程应用中,考虑到震动波传播以及各项异性介质等因素的影响,传统线性定位求解过程极易出现发散问题,于是采用数学算法结合微震定位原理,推导得到一种微震非线性优化定位算法;新算法通过引入下山因子,增强了算法的稳定性和收敛性,达到全局收敛的目的;并提出一种多方向迭代的思路,可以使定位结果更加科学和精确,能够有效地降低定位结果中各个方向上的误差;通过长方体煤块声发射震源试验和传统线性定位算法进行比较,使算法的稳定性和震源结果的准确性得到了验证;工程现场应用也证明了它能够有效地降低微震台网布设带来的影响。

关键词：微震定位线性非线性优化定位

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多场耦合的冲击地压防治研究

Applied Geophysics 2024年第1期21卷 119-132,205页

作者：刘伟建侯梦杰董森森肖扬邓志刚王浩楠张志增中原工学院建筑工程学院郑州451100 郑州安岩智能科技有限公司郑州450000 煤炭科学技术研究院有限公司北京100013

研究煤岩体中断层、采空区、陷落柱等异常地质体的活化规律,对煤矿开采过程中可能发生的冲击地压、煤与瓦斯突出、突水等地质灾害进行及时预警,对回采过程中长壁工作面斜交正断层围岩应力场和位移场演变特征进行数值模拟,同时采用高精... 详细信息

研究煤岩体中断层、采空区、陷落柱等异常地质体的活化规律,对煤矿开采过程中可能发生的冲击地压、煤与瓦斯突出、突水等地质灾害进行及时预警,对回采过程中长壁工作面斜交正断层围岩应力场和位移场演变特征进行数值模拟,同时采用高精度微地震监测系统对其活化孕灾过程进行监测,将数值模拟结果和微震监测结果进行耦合分析。结果表明:断层和采空区附近的煤岩体属于高应力区,发生微震事件频次高,能量大,工作面推采至断层处顶板的位移变化更加显著。本文采用微地震监测和数值模拟耦合分析方法,能够有效地揭示煤岩中异常地质体活化过程,对冲击地压灾害进行预警,该方法为具有相同类型地质特点的工作面安全回采提供了参考。

关键词：微地震监测数值模拟断层耦合分析

Control of aluminum distribution in ZSM-5 zeolite for enhancement of its catalytic performance for propane aromatization

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Frontiers of Chemical Science and Engineering 2024年第8期18卷 15-24页

作者： Zhao Ma Dezhi Shi sen Wang Mei dong Weibin Fan State Key Laboratory of Coal Conversion Institute of Coal ChemistryChinese Academy of SciencesTaiyuan 030001China University of Chinese Academy of Sciences Beijing 100049China

Regulation of aluminum distribution in zeolite framework is an effective method for improving its catalytic performance for propane ***,we found that recrystallization and post-realuminization of ZSM-5 cannot only create hollow structures to enhance the diffusion ability,but also adjust the content and position of paired aluminum species in its *** characterizations results confirmed that increase of paired aluminum content and inducement of more aluminum atoms sited in the intersection cavity are beneficial to the formation of aromatic products in propane *** a result,the hollow-structured ZSM-5 zeolite with more paired aluminum(H-200-hollow)showed higher propane conversion and aromatics selectivity than other samples at the same *** catalytic performance of H-200-hollow can be further improved by ion-exchanging with a small amount of Ga(III)*** propane conversion and aromatics selectivity of Ga-200-hollow reached as high as 95%and 70%,respectively,at 540°C and 1 atm.

关键词： propane aromatization zeolite aluminum distribution recrystallization and post-realuminization

Robust Carbon-Carbon Cleavage in Lignin to Produce Phenol and Cyclohexanone

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Chemical Research in Chinese Universities 2024年第1期40卷 29-35页

作者： WANG Lulin CHENG Xiaomeng dong Minghua LUAN sen WU Yuxuan HAN Buxing LIU Huizhen Beijing National Laboratory for Molecular Sciences CAS Laboratory of Colloid and Interface and ThermodynamicsCAS Research/Education Center for Excellence in Molecular SciencesCenter for Carbon Neutral ChemistryInstitute of ChemistryChinese Academy of SciencesBeijing 100190P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China

The challenge of breaking 5-5'bonds in lignin,attributed to their high bonding energy,has prompted the development of a new transformation ***,an important model compound for lignin,contains these 5-5'bonds,making it crucial to devise a strategy for their cleavage in lignin *** study introduces a novel method for transforming biphenyl,involving selective hydrogenation to cyclohexylbenzene by Ni/SiO2 catalyst,followed by its oxidation to phenol and cyclohexanone through a radical *** demonstrate that the catalysts with small particles have strong catalytic activity,while there is little difference in *** reason for the high selectivity of cyclohexylbenzene is due to the limited adsorption of cyclohexylbenzene on Ni/*** work presents a fresh approach to breaking resilient C-C bonds in lignin.

关键词： Lignin 5-5'Bond Ni/SiO_(2) Phenol

Cuproptosis mediates copper-induced testicular spermatogenic cell death

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Asian Journal of Andrology 2024年第3期26卷 295-301页

作者： Jing-Yi Zhang Xu-Jun Yu Jun-Jun Li Yao Xiao Guang-sen Li Fang Yang Liang dong Chengdu University of Traditional Chinese Medicine Chengdu 611137China Chengdu Fifth People’s Hospital The Fifth People’s Hospital of Chengdu University of Traditional Chinese MedicineChengdu 611130China TCM Regulating Metabolic Diseases Key Laboratory of Sichuan Province Hospital of Chengdu University of Traditional Chinese MedicineChengdu 610072China Department of Surgery The Reproductive and Women-Children HospitalChengdu University of Traditional Chinese MedicineChengdu 610041China

Cuproptosis,a novel mechanism of programmed cell death,has not been fully explored in the context of spermatogenic *** investigated the potential involvement of cuproptosis in spermatogenic cell death using a mouse model of copper *** male Institute of Cancer Research(ICR)mice were randomly divided into four groups that received daily oral gavage withsodium chloride(control)or copper sulfate(CuSO_(4))at 50 mg kg^(−1),100 mg kg^(−1),or 200 mg kg^(−1),for 42 consecutive *** to copper overload exhibited a disruption in copper ***,significant upregulated expression of keycuproptosis factors was accompanied by a significant rise in the rates of testicular tissue cell *** revealed the presence of ferredoxin 1(Fdx1)in Sertoli cells,Leydig cells,and spermatogenic cells at various stages oftesticular development,and the Fdx1-positive staining area was significantly increased in copper-overloaded *** and decreased adenosine triphosphate levels were also observed,further implicating mitochondrial damage *** analyses revealed pathological lesions and blood−testis barrier destruction in the testicular tissue,accompaniedby decreased sperm concentration and motility,in copper-overloaded *** summary,our results indicate that copper-overloadedmice exhibit copper homeostasis disorder in the testicular tissue and that cuproptosis participates in spermatogenic cell *** findings provide novel insights into the pathogenic mechanisms underlying spermatogenic cell death and provide initialexperimental evidence for the occurrence of cuproptosis in the testis.

关键词： blood−testis barrier cuproptosis ferredoxin 1 spermatogenic cell death

Novel variants in DNAH6 cause male infertility associated with multiple morphological abnormalities of the sperm flagella(MMAF)and ICSI outcomes

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Asian Journal of Andrology 2024年第1期26卷 91-98页

作者： Zhong-Mei Shao Yu-Tong Zhu Meng Gu sen-Chao Guo Hui Yu Kuo-Kuo Li dong-dong Tang Yu-Ping Xu Ming-Rong Lv Reproductive Medicine Center Department of Obstetrics and Gynecologythe First Affiliated Hospital of Anhui Medical UniversityHefei 230022China Department of Obstetrics and Gynecology Fuyang Hospital of Anhui Medical UniversityFuyang 236112China NHC Key Laboratory of Study on Abnormal Gametes and Reproductive Tract(Anhui Medical University) Hefei 230032China Key Laboratory of Population Health Across Life Cycle(Anhui Medical University) Ministry of Education of the People'sRepublicof ChinaHefei 230032China

Variations in the dynein axonemal heavy chain gene,dynein axonemal heavy chain 6(DNAH6),lead to multiple morphological abnormalities of the *** studies have reported that these deficiencies may result in sperm head ***,whether DNAH6 is also involved in human acrosome biogenesis remains *** purpose of this study was to investigate DNAH6 gene variants and their potential functions in the formation of defective sperm heads and ***-exome sequencing was performed on a cohort of 375 patients with asthenoteratozoospermia from the First Affiliated Hospital of Anhui Medical University(Hefei,China).Hematoxylin and eosin staining,scanning electron microscopy,and transmission electron microscopy were performed to analyze the sperm morphology and *** staining and Western blot analysis were conducted to examine the effects of genetic *** identified three novel deleterious variants in DNAH6 among three unrelated *** absence of inner dynein arms and radial spokes was observed in the sperm of patients with DNAH6 ***,deficiencies in the acrosome,abnormal chromatin compaction,and vacuole-containing sperm heads were observed in these patients with DNAH6 *** decreased levels of the component proteins in these defective structures were further confirmed in sperm from patients with DNAH6 variants using Western *** intracytoplasmic sperm injection(ICSl)treatment,the partner of one patient with a DNAH6 variant achieved successful ***,novel variants in DNAH6 genes that contribute to defects in the sperm head and flagella were identified,and the findings indicated Icsl as an effective clinical treatment for such patients.

关键词： asthenoteratospermia DNAH6 intracytoplasmic sperm injection male infertility

Recent advances in COhydrogenation to higher alcohols

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Science China Chemistry 2024年

作者： Qian Zhang sen Wang Mei dong Jianguo Wang Weibin Fan State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

CO2hydrogenation to higher alcohols(C2+OH) is an effective way to realize carbon recycling, which can not only reduce the CO2amounts in atmosphere and mitigate the greenhouse effect, but also provides a new route to synthesize important ***, this process is a challenge because the inert CO2molecule is difficult to be activated and undergo C–C coupling. The key to achieve selective conversion of CO2to C2+OH is to design high-performance catalytic systems and unravel the reaction mechanism. In this review, we report several typical CO2hydrogenation-to-C2+OH catalyst materials, including noble-metal catalysts, Cu-based catalysts, Co-based catalysts and Mo-based catalysts, and evaluate the effects of various promoters on the catalytic performance and reaction mechanism. It will provide not only fundamental insights into the CO2hydrogenation-toC2+OH reaction mechanism, but also guidance for the development of related high-performance catalysts.

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Recent progress in the deactivation mechanism of zeolite catalysts in methanol to olefins

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Science China Chemistry 2024年

作者： Sheng Fan Han Wang sen Wang Mei dong Weibin Fan State Key Laboratory of Coal Conversion Institute of Coal Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

Methanol to olefins(MTO) as an important reaction in C1 chemistry can effectively transform non-petroleum carbon resources into value-added chemicals. Zeolites have been widely used as MTO catalysts. However, they usually suffer from a rapid deactivation due to bulky coke species production, and thus require continuous regenerations in industrial application. The key to design and develop highly stable zeolite catalysts for MTO process is to unravel the deactivation mechanism and clarify the structure–performance relationship of catalysts. Here, in this mini-review, we investigate the critical intermediate species inducing zeolite deactivation and analyze the formation and evolution pathways of polycyclic aromatic hydrocarbons(PAHs)that are the precursors of carbonaceous deposits. In addition, some methods to alleviate the coking mainly including acid regulation, morphology modification and process optimization, are also summarized.

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The hard X-ray nanoprobe beamline at the SSRF

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Nuclear Science and Techniques 2024年第7期35卷 79-88页

作者： Yan He Hui Jiang dong-Xu Liang Zhi-sen Jiang Huai-Na Yu Hua Wang Cheng-Wen Mao Jia-Nan Xie Ai-Guo Li Shanghai Advanced Research Institute Chinese Academy of SciencesShanghai201210China

The hard X-ray nanoprobe beamline BL13U is a phase-Ⅱ beamline project at the Shanghai Synchrotron Radiation *** beamline aims to enable comprehensive experiments at high spatial resolutions ranging from 50 to 10 nm. The X-ray energy range of the beamline, 5–25 keV, can detect most elements in the periodic table. Two operating modes were designed to accommodate the experimental requirements of high-energy resolution or high photon flux, respectively. X-ray nanofluorescence, nanodiffraction, and coherent diffraction imaging are developed as the main experimental techniques for BL13U. This paper describes the beamline optics, end station configurations, experimental methods under development, and preliminary test results. This comprehensive overview aims to provide a clear understanding of the beamline capabilities and potential applications.

关键词： Shanghai synchrotron radiation facility Hard X-ray nanoprobe X-ray nanofocusing

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