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Trace Element Geochemistry of Magnetite from the Fe(-Cu) Deposits in the Hami Region, Eastern Tianshan Orogenic Belt, NW China

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Acta Geologica Sinica(English Edition) 2014年第1期88卷 176-195页

作者： HUANG Xiaowen QI Liang meng yumiao State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

Laser ablation–inductively coupled plasma–mass spectrometry（LA–ICP–MS） was used to determine the trace element concentrations of magnetite from the Heifengshan, Shuangfengshan, and Shaquanzi Fe（–Cu） deposits in the Eastern Tianshan Orogenic Belt. The magnetite from these deposits typically contains detectable Mg, Al, Ti, V, Cr, Mn, Co, Ni, Zn and Ga. The trace element contents in magnetite generally vary less than one order of magnitude. The subtle variations of trace element concentrations within a magnetite grain and between the magnetite grains in the same sample probably indicate local inhomogeneity of ore–forming fluids. The variations of Co in magnetite between samples are probably due to the mineral proportion of magnetite and pyrite. Factor analysis has discriminated three types of magnetite： Ni–Mn–V–Ti（Factor 1）, Mg–Al–Zn（Factor 2）, and Ga– Co（Factor 3） magnetite. Magnetite from the Heifengshan and Shuangfengshan Fe deposits has similar normalized trace element spider patterns and cannot be discriminated according to these factors. However, magnetite from the Shaquanzi Fe–Cu deposit has affinity to Factor 2 with lower Mg and Al but higher Zn concentrations, indicating that the ore–forming fluids responsible for the Fe–Cu deposit are different from those for Fe deposits. Chemical composition of magnetite indicates that magnetite from these Fe（–Cu） deposits was formed by hydrothermal processes rather than magmatic differentiation. The formation of these Fe（–Cu） deposits may be related to felsic magmatism.

关键词： trace elements,magnetite,LA–ICP–MS,Fe（–Cu） deposits,Eastern Tianshan Orogenic Belt,Xinjiang

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Germanium in Magnetite:A Preliminary Review

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Acta Geologica Sinica(English Edition) 2017年第2期91卷 711-726页

作者： meng yumiao HU Ruizhong HUANG Xiaowen GAO Jianfeng State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China

Magnetite is a very common mineral in various types of iron deposits and some sulfide deposits. Recent studies have focused on the use of trace elements in magnetite to discriminate ore types or trace ore-forming process. Germanium is a disperse element in the crust, but sometimes is not rare in magnetite. Germanium in magnetite can be determined by laser ablation ICP-MS due to its low detection limit（0.0X ppm）. In this study, we summary the Ge data of magnetite from magmatic deposits, iron formations, skarn deposits, iron oxide copper-gold deposits, and igneous derived hydrothermal deposits. Magnetite from iron formations contains relatively high Ge（up to ~250 ppm）, whereas those from all other deposits mostly contains Ge less than 10 ppm, indicating that iron formations can be discriminated from other Fe deposits by Ge contents. Germanium in magmatic/hydrothermal magnetite is controlled by a few factors. Primary magma/fluid composition may be the major control of Ge in magnetite. Higher oxygen fugacity may be beneficial to Ge partition into magnetite. Sulfur fugacity and temperature may have little effect on Ge in magnetite. The enrichment mechanism of Ge in magnetite from iron formations remains unknown due to the complex ore genesis. Germanium along with other elements（Mn, Ni, Ga） and element ratios（Ge/Ga and Ge/Si raios） can distinguish different types of deposits, indicating that Ge can be used as a discriminate factor like Ti and V. Because of the availability of in situ analytical technique like laser ablation ICP-MS, in situ Ge/Si ratio of magnetite can serve as a geochemical tracer and may provide new constraints on the genesis of banded iron formations.

关键词： germanium magnetite controlling factor iron deposits discriminate factor

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Trace element and sulfur isotope compositions of pyrite from the Tianqiao Zn–Pb–Ag deposit in Guizhou province,SW China:implication for the origin of ore-forming fluids

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Acta Geochimica 2022年第2期41卷 226-243页

作者： yumiao meng Xiaowen Huang Chunxia Xu Songning meng State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550081China School of Hydraulic and Ecological Engineering Nanchang Institute of TechnologyNanchang 330099China Applied Nuclear Technology in Geosciences Key Laboratory of Sichuan Province Chengdu University of TechnologyChengdu 610059SichuanChina

The Tianqiao Zn–Pb–Ag deposit in SW China,hosted by Devonian and Carboniferous limestone and clay rocks,is composed of sulfides such as sphalerite,galena,and pyrite.Pyrite is present in different paragenetic stages and can be divided into four types based on textures and mineral assemblages.Pyrite from the adjacent Shanshulin deposit(Py-SSL)is also used for comparison.Py1 shows framboid texture with grain diameter up to 1 mm and was commonly replaced by sphalerite.Py2 is characterized by overgrowth texture and displays inner oscillatory zoning.Py2 is associated with abundant sphalerite and galena.Py3 shows replacement relics textures where galena fills the fractures of pyrite.Py4 is a euhedral to subhedral crystal disseminated in dolomite and is characterized by deformation and fragmentation textures.Minor sphalerite and galena are associated with Py4.Py-SSL is subhedral and disseminated in dolomite,similar to Py4.Py1 was formed by a diagenetic or sedimentary process,whereas Py2 and Py3 were formed by multiple stages of ore fluids.Py4 and Py-SSL were formed at the carbonate-sulfide stage,but Py4 suffered from deformation after its formation.Py1,Py2,and Py3 are characterized by relative enrichment of Sb,Cu,and As,in contrast to Py4 and Py-SSL with higher Cr,W,Ge,Sn,Tl,Ni,and Ga contents.However,critical metals such as Ge,Ga,and In in pyrite are generally lower than10 ppm,which are not economically important.The trace element variation in Tianqiao pyrite with paragenesis results from fluid evolution in the Pb–Zn ore system and competition with co-precipitating minerals.Diagenetic and ore-forming hydrothermal fluids are responsible for the formation of different types of pyrite.Ore-related pyrite from the Tianqiao and Shanshulin deposits has Co and Ni distribution features similar to pyrite from sedimentary pyrite and submarine hydrothermal vents,different from those in volcanogenic massive sulfide,iron oxide-copper–gold,and porphyry Cu deposits,indicating their derivation of relatively low-temperature(<~250°C)hydro

关键词： Trace elements Pyrite Sulfur isotopes Tianqiao and Shanshulin Zn-Pb-Ag Origin of oreforming fluids

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Ionic liquid-trimetallic electrocatalytic system for C–O bond cleavage in lignin model compounds and lignin under ambient conditions

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Nano Research 2024年第4期17卷 2420-2428页

作者： Guangyong Liu yumiao Lu JunFeng Lu Yanlei Wang Shijing Liang Hongyan He Lilong Jiang National Engineering Research Center of Chemical Fertilizer Catalyst Fuzhou UniversityFuzhou 350002China CAS Key Laboratory of Green Process and Engineering State Key Laboratory of Multiphase Complex SystemsBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190China Longzihu New Energy Laboratory Zhengzhou Institute of Emerging Industrial TechnologyZhengzhou 450000China

Electrocatalytic depolymerization of lignin into value-added chemicals offers a promising technique to make biorefining sustainable.Herein,we report a robust trimetallic PdNiBi electrocatalyst for reductive C–O bond cleavage of different lignin model dimers and oxidized lignin under mild conditions.The reduction reaction proceeds with complete substrate conversion and excellent yields toward monomers of phenols(80%–99%)and acetophenones(75%–96%)in the presence of an ionic liquid electrolyte with operational stability.Systematic experimental investigations together with density functional theory(DFT)calculations reveal that the outstanding performance of the catalyst results from the synergistic effect of the metal elements,which facilitates the easier formation of a key Cαradical intermediate and the facile desorption of the as-formed products at the electrode.The results open up new opportunities for lignin valorization through the green electrocatalytic approach.

关键词： electrocatalytic depolymerization lignin Ionic liquids density functional theory(DFT)calculation

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Recent Advances in Biomass-derived Porous Carbon Materials:Synthesis,Composition and Applications

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Chemical Research in Chinese Universities 2024年第1期40卷 3-19页

作者： ZHAI Ziqi LU yumiao LIU Guangyong DING Wei-Lu CAO Bobo HE Hongyan CAS Key Laboratory of Green Process and Engineering State Key Laboratory of Mesoscience and EngineeringBeijing Key Laboratory of Ionic Liquids Clean ProcessInstitute of Process EngineeringChinese Academy of SciencesBeijing 100190P.R.China University of Chinese Academy of Sciences Beijing 100049P.R.China Longzihu New Energy Laboratory Zhengzhou Institute of Emerging Industrial TechnologyZhengzhou 450000P.R.China

Porous carbon materials(PCMs)play a pivotal role in diverse applications,such as energy storage,adsorption,catalysis,environmental remediation,and microwave adsorption.The selection of carbon precursors,in particular,is crucial for tailoring porous structures with specific functionalities.Biomass,with its rich carbon feedstock,abundant availability,renewability,and versatile structures,has emerged as a promising precursor for porous carbon material synthesis.This review comprehensively summarizes the recent advances in biomass-derived porous carbon materials(BPCMs)encompassing synthetic strategy,morphology,structural composition,and multiple applications.We first review synthetic approaches aiming at regulating porosity,followed by morphological and composition features of BPCMs,with a special emphasis on elucidating the dimensional clarification and heteroatom doping effects.The discussion then extends to the wide-ranging applications of BPCMs,covering energy-related applications and CO_(2) adsorption to environmental remediation.Finally,the review outlines the existing challenges and prospects in the field.In summary,this review systematically describes BPCMs and provides valuable guidance for researchers to select and synthesize BPCMs that meet specific functional requirements.

关键词： Biomass Porous carbon Pyrolysis Heteroatom-doping Supercapacitor CO_(2)adsorption

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Multiscale causes of the 2022 Yangtze mega-flash drought under climate change

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Science China Earth Sciences 2024年第8期67卷 2649-2660页

作者： Xing YUAN yumiao WANG Shiyu ZHOU Hua LI Chenyuan LI School of Hydrology and Water Resources Nanjing University of Information Science and Technology Institute of Atmospheric Physics Chinese Academy of Sciences Key Laboratory of Hydrometeorological Disaster Mechanism and Warning of Ministry of Water Resources Nanjing University of Information Science and Technology

The 2022 Yangtze mega-flash drought is characterized by strong intensity and rapid development both in time and space, accompanied by a persistent anticyclonic circulation anomaly. However, the causes of the extreme event remain elusive given the multiscale nature of drought. Here we presented a brief overview for the oceanic and terrestrial causes of the megaflash drought during the summer of 2022, and estimated the risk in a changing climate. Using the soil moisture percentile as the drought index, it was found that the drought expanded to the entire Yangtze River basin within two months, with 80% of basin under severe drought conditions at the end of August. Both the intensity and onset speed of the 2022 mega-flash drought were ranked as the first during the past 62 years, with return periods of 86 and 259 years, respectively. The results of composite analysis showed that the spring La Ni?a can facilitate the abrupt change from a wet/normal condition in May–June to drought in July–August over the Yangtze River basin, which was beneficial for the increase of flash drought intensity and onset speed in2022. The analysis through the linear regression also indicated that the unprecedented intensity was associated with the negative phase of the Pacific Decadal Oscillation. Quantified by a coupling strength index for soil moisture and vapor pressure deficit, it was found that there was a strong land-atmosphere coupling over the Yangtze River basin during July–August 2022. The attribution by using CMIP6 climate models suggested that land-atmosphere coupling increased the risks of flash drought intensity and onset speed like 2022 by 61%±6% and 64%±7% under natural climate forcings, and the synergy of coupling and anthropogenic climate change would increase the risks by 75%±22% and 85%±12%. Our findings emphasized the role of landatmosphere coupling combined with anthropogenic climate change in intensifying flash droughts.

关键词： Flash drought Yangtze River basin Land-atmosphere coupling Climate change Attribution

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Effectiveness of Comprehensive Nursing Management in Enhancing Blood Donation Outcomes and Donor Experience: A Comparative Study

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Journal of Clinical and Nursing Research 2024年第5期8卷 277-282页

作者： yumiao Zhang Suzhou Wujiang Blood Station Suzhou 215200Jiangsu ProvinceChina

Objective:To assess the management effect of comprehensive nursing management on blood donation services in blood stations.Methods:Sixty-four individuals who donated blood at a blood station between September 2021 and September 2023 were selected and randomly assigned into two groups of 32 each.The first group received comprehensive nursing management,while the second group received routine nursing management.Blood donation indexes and observational indexes such as adverse reactions were compared between the groups.Results:The total blood donation volume and qualified blood donation volume were higher in the first group than in the second group.The amount of discarded blood and the rate of blood discards were lower in the first group compared to the second group(P<0.05).Additionally,the adverse reaction rate in the first group was lower,the blood donation comfort scores were higher,the psychological state scores were lower,and the quality of care scores were higher than those in the second group(P<0.05).Conclusion:Comprehensive nursing management can improve the efficiency of blood donation,reduce the rate of blood discards,decrease the incidence of adverse reactions,alleviate negative psychological states of blood donors,and enhance both the comfort level of blood donation and the quality of care provided.

关键词： Comprehensive nursing management Blood donation service at blood stations Adverse reactions Comfort Quality of care

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磷灰石化学组成研究进展:成岩成矿过程示踪及对矿产勘查的指示

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岩石学报 2022年第10期38卷 3067-3084,I0013-I0015页

作者：谭侯铭睿黄小文漆亮高剑峰孟郁苗谢欢中国科学院地球化学研究所矿床地球化学国家重点实验室贵阳550081 中国科学院大学北京100049

磷灰石广泛分布于各类岩石和矿床中,根据其F、OH以及Cl阴离子种类可分为氟磷灰石、氯磷灰石和羟基磷灰石。磷灰石对其自身结构的变形以及化学取代有良好的耐受性,一系列元素可以替代磷灰石中的Ca、P、F、Cl和OH,因此其化学组成复杂。磷... 详细信息

磷灰石广泛分布于各类岩石和矿床中,根据其F、OH以及Cl阴离子种类可分为氟磷灰石、氯磷灰石和羟基磷灰石。磷灰石对其自身结构的变形以及化学取代有良好的耐受性,一系列元素可以替代磷灰石中的Ca、P、F、Cl和OH,因此其化学组成复杂。磷灰石中Ca位存在两种不同的阳离子位置,影响不同元素在这两种位置取代的因素包括离子半径、价态以及磷灰石的种类等。岩浆过程中,稀土(REE)、Y、Sr是磷灰石中的相容元素,而F、Cl、OH的相容性随物理化学条件不同而变化。相较于元素在磷灰石与熔体相间的分配研究,目前对于元素在磷灰石与流体相间的分配研究较少。磷灰石化学组成可以判别母岩类型:如F、Cl、As、V含量可以区分I型与S型花岗岩;REE、Sr、Y、Mn、As、Th的含量、轻稀土(LREE)的富集程度和球粒陨石标准化稀土元素配分模式可以用于判别碳酸岩、二辉橄榄岩、镁铁质岩石等岩石类型。利用磷灰石的F、Cl和CO等挥发分的含量,并结合Sr-Nd同位素组成,可以识别地幔源区及其流体交代作用。磷灰石Sr/Th与La/Sm的变化可用于指示岩浆来自脱水板块或熔融沉积物。磷灰石的主微量元素(Mn、Eu)含量或元素比值(F/Cl)能够反映岩浆的分异程度,而且Ce/Pb和Th/U比值可以反映岩浆形成过程中流体参与程度。磷灰石中的变价元素如Eu、Ce、Ga和S含量及δEu和δCe可用于推断岩浆的氧化还原状态。由于磷灰石对热液交代作用非常敏感,所以磷灰石的结构和化学组成已广泛用于成矿过程研究。在与花岗岩有关的关键金属矿床中,磷灰石的主、微量元素含量和Sr-Nd同位素比值常常用于区分不同花岗质岩浆的源区特征,δCe、δEu也可以用于指示花岗质侵入体的氧化还原状态;斑岩有关的多金属矿床F、Cl、S、Mn含量以及F/Cl比值能够指示成矿岩浆-热液的来源及演化,δCe、δEu可以用于指示岩浆热液的氧逸度;铁氧化物-铜-金和铁氧化物-磷灰石矿床中磷灰石结构、共生稀土矿物结合Na、F、Cl以及REE含量能够反映与成矿有关的岩浆-流体作用以及流体性质。磷灰石中Mn、Fe、REE、Y、F、Cl、SO_(3)的含量或比值的差异可用于判别矿化与未矿化的岩石或者蚀变类型,并用于区分不同矿床类型等,对矿产勘查具有一定指示意义。磷灰石化学组成结合机器学习方法,可以更好地识别磷灰石的来源。综上所述,磷灰石作为一种新兴的指示矿物,除了在成岩和成矿过程示踪方面体现出独特优势,在矿产勘查应用方面也具有重要的应用前景。

关键词：磷灰石结晶结构分配系数岩石成因成矿示踪矿产勘查

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Predictive value of T cell receptor repertoire profiling for immunosuppressive therapy in severe aplastic anemia

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Genes & Diseases 2024年第1期11卷 95-98页

作者： Cunte Chen Yuling Zhang Dongpei Lu Zelong Zhang Jun Yang Xiaowei Chen Ming Zhou Wenjian Mo Caixia Wang Qinghua Cai yumiao Li Ruiqing Zhou Shilin Xu Wei Zhou Tingfen Deng Shiyi Pan Yanli Xu Shunqing Wang Yuping Zhang Department of Hematology Guangzhou First People's HospitalSouth China University of TechnologyGuangzhouGuangdong 510180China Guangzhou Junruikang Biotechnology Co. LtdGuangzhouGuangdong 510700China

Increasing evidence supports the hypothesis of autologous immune attack in severe aplastic anemia(SAA):the predominant role of activated cytotoxic T cells(CTL)expressing-interferon in inhibiting the growth of bone marrow(BM)cells,putative autoantigens,and oligoclonal expansion of CD8+T cells.1 For SAA patients,the definitive therapies are immunosuppressive therapy(IST)or hematopoietic stem transplantation(HSCT).

关键词： anemia aplastic interferon

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CFO变更与企业财务报告质量

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南京审计大学学报 2024年第3期21卷 34-49页

作者：余玉苗章志卓武汉大学经济与管理学院湖北武汉430072

在现代风险导向审计模式下,审计师会关注CFO变更这一信号以识别和评估财务报表重大错报风险,但鲜有文献探究财务报告质量是否因此而下降。以2010—2020年沪深两市A股上市公司为对象,研究CFO变更对企业财务报告质量的影响。研究表明,CFO... 详细信息

在现代风险导向审计模式下,审计师会关注CFO变更这一信号以识别和评估财务报表重大错报风险,但鲜有文献探究财务报告质量是否因此而下降。以2010—2020年沪深两市A股上市公司为对象,研究CFO变更对企业财务报告质量的影响。研究表明,CFO变更提高了企业应计盈余管理的程度,增加了企业报告小额盈余、进行财务重述以及被出具非标审计意见的可能性,进而导致财务报告质量显著下降;当CFO未兼任内部董事、发生外部继任或非正常变更、任职于非央企时,上述负向作用更加明显。进一步研究表明,CFO变更通过提高企业的代理成本与信息不对称程度从而降低财务报告质量,并最终使企业面临更大的融资约束。

关键词： CFO变更财务报告质量异常应计小额盈余财务重述审计意见融资约束

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