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Atacamite and Nantokite in Kaerqueka Copper Deposit of Qimantag Area:Evidence for Cenozoic Climate Evolution of the Qaidam Basin

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Journal of Earth Science 2017年第3期28卷 492-499页

作者： liwen yi Xiangping Gu Anhuai Lu Xiangyu Li Dexian Zhang Zhiling Wang Jianping Liu Shuai Li Zhengxiang Shu Cui Yu Hongyan Zuo Can Shen College of Resources and Environmental Sciences Hunan Normal UniversityChangsha 410081China Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitor Ministry of EducationChangsha 410083China School of Geosciences and Info-Physics Central South UniversityChangsha 410083China Hunan Institute of Geological Survey Changsha 410116China

Using a mineralogy method to reflect climate evolution is a new approach to research Cenozoic environmental progression of the Qaidam Basin. In this paper, we present the chemical composition and crystallographic parameter of atacamite, nantokite, and tenorite in cryptocrystalline aggregates from the Kaerqueka copper deposit of Qimantag metallogenic belt by means of electron microprobe and in-situ X-ray diffraction analyses. Atacamite and nantokite occur in an intimate intergrowth as the secondary precipitation of chalcopyrite and bornite filling in the interstitial space of andradite in the Kaerqueka copper deposit, with an average composition of Cl： 12.38 wt.%, Cu： 63.76 wt.%, O： 21.46 wt.%. X-ray microdiffraction shows that the intergrowth contains nantokite with a cubic unit cell a=5.403（2）？ and atacamite with an orthorhombic unit cell a=6.030（3）, b=6.883（2）, c=9.114（1）？. XRD quantitative calculation shows that the nanometric aggregate contains 36.07 wt.% tenorite, 18.41 wt.% atacamite, and 45.52 wt.% nantokite. The presence of nantokite and atacamite requires saline solutions for their formation and hyper-arid climate conditions for their preservation. Combined with the data of salt lakes and the pollen sequence of western China, we suggest that during the uplift of the Tibetan Plateau and the retreat of the Paratethys, saline water was forced to the surface through a basal fracture zone. In the hyper-arid climate of the Qaidam Basin, the recharge of groundwater by direct precipitation is negligible, and groundwater is derived from inflow from the salt lakes. Thus, atacamite is preserved. In addition, spertiniite in the edge and fractures of atacamite and nantokite may represent wetter climate after the formation of atacamite and nantokite.

关键词： atacamite nantokite climate evolution Qaidam Basin

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Determination of Fe^(2+)/Fe^(3+)Ratios of Magnetite using Different Methods:A Case Study from the Qimantag Metallogenic Belt

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Acta Geologica Sinica(English Edition) 2022年第6期96卷 2135-2147页

作者： yi liwen LI Qiuping LU Anhuai GU Xiangping CHI Guoxiang School of Geographical Sciences Hunan Normal UniversityChangsha 410081China School of Geosciences and Info-Physics Central South UniversityChangsha 410083China School of Earth and Space Sciences Peking UniversityBeijing 100871China Department of Geology University of ReginaReginaSaskatchewan S4S 0A2Canada

Determination of Fe^(2+)/Fe^(3+) ratios from metallogenic belts to explore controlling physical and chemical conditions of rock formation is of great significance.In order to explore magnetite Fe^(2+)/Fe^(3+) ratios of the Qimantag metallogenic belt,part of the Eastern Kunlun orogenic belt in the northeastern margin of the Qinghai–Tibetan plateau,western Central Orogenic Belt of China,and overcome the limitation of the traditional electronic probe,five different measurement methods are proposed and their respective advantages and disadvantages evaluated,with the composition data of the magnetite obtained using electron probe microanalysis(EPMA).The direct oxygen measurement method has a significant impact on the determination results of FeO and Fe2O3,but the accuracy and uniformity of the results are low.The valence method(Flank method)based on the spectral intensity ratio of Lαto Lβfor iron is also unreliable for FeO and Fe_(2)O^(3) measurements because it is difficult to establish a relationship between Lβ/Lα,the spectral intensity ratio,and the Fe^(2+)/Fe^(3+) content ratio.In comparison,the charge difference method,the surplus-oxygen method and the Mössbauer spectrum method are still the most favorable.Mössbauer spectroscopy,with its isomer movement particularly sensitive to the oxidation state of iron,yields results closer to 0.5,which is relatively reliable.Earlier magnetite deposits are located in intrusions or contact zones and formed by magmatic fluids with high Fe2+/Fe3+ratios,whereas later magnetite deposits are farther away from intrusions and have low Fe^(2+)/Fe^(3+) ratios.The transformation mechanism of hematite and magnetite in the Qimantage metallogenic belt is also studied.No large volume changes,such as pore filling and shrinkage fracture,were detected in the metallogenic belt,and the transformation mechanism is more similar to a reoxidation and reduction mechanism.

关键词： iron magnetite direct oxygen measurement flank-charge difference-surplus-oxygen methods Mössbauer spectra Qimantage

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Re-Os Isotopic Age of Molybdenite of the Jingren Deposit and its Mineralogical Significance of Magnetite,Pyrite and Chalcopyrite

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Acta Geologica Sinica(English Edition) 2021年第4期95卷 1236-1248页

作者： CAO Li yi liwen DAI Wei XIE Binggeng LI Xiaoqing LU Anhuai GU Xiangping College of Geographic Sciences Hunan Normal UniversityChangsha 410081China Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitoring(Central South University) Ministry of EducationChangsha 410083China The Third of Qinghai Geological and Mineral Exploration Institute Xining 810012China College of Geosciences and Info-Physics Central South UniversityChangsha 410083China

The Jingren deposit is part of the Qimantage metallogenic belt within the eastern Kunlun orogenic belt,the largest metallogenic belt in Qinghai Province,northwestern China.Exploration data show that the metal resources of the Jingren deposit are greater than 93000 t in a mining area of 76.15 km2,which indicates significant exploration potential in the near future.Three W–E-trending faults,F1-3,dominate the extension of the mineralization zone,which consists of chalcopyrite,pyrite,magnetite,galena,sphalerite,and molybdenite as well as bismuth-bearing minerals.The deposit contains a large amount of late Triassic intrusive rocks,however,previous research did not reach a consensus on the timing or the origin of the mineralization owing to a lack of geochronological data and poor exposure conditions.In the present study,Re-Os isotopic dating from six molybdenite samples collected from a borehole of the granodiorite in the Jingren deposit using negative thermal ionization mass spectrometry(NTIMS)showed 187 Re and 187 Os concentrations of 0.26–4.40 ppm and 1.03–16.46 ppb,respectively,with an initial 187 Os/188 Os value of 0.06±0.19.This proves that the Jingren deposit has a metallogenic age of(225±4)Ma and is the product of united mineralization of the Qimantage metallogenic belt and that the Jingren deposit might actually be an Indosinian metallogeny.In addition,the Re content of these samples,at 0.42 ppm to 7.00 ppm shows that the mineralization was derived mainly from a crustal source.Furthermore,electron probe microanalysis(EPMA)conducted on chalcopyrite obtained from 22 metallic mineral samples revealed(Fe+Cu)/S ratios of 1.801–1.947 with an average of 1.852,which is lower than the ideal value(1.875).Besides,the main ore body formed in a relatively higher temperature environment than the surrounding rocks in the Jingren deposit.These data indicate that the Jingren deposit formed in a metallogenic environment at lower temperature.Moreover,according to the TiO_(2)-Al_(2)O_(3)-(MgO+MnO)and TiO_(2)-Al_(2)O_(3)-MgO gene

关键词： mineralogy Re-Os isotopic dating molybdenite skarn Indosinian Jingren deposit Qimantage metallogenic belt

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High-performance piezoresistive sensors based on transfer-free large-area PdSe_(2) films for human motion and health care monitoring

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InfoMat 2024年第1期6卷 139-149页

作者： Rui Zhang Jie Lin Tao He Jiafang Wu Zhuojun Yang liwen Liu Shaofeng Wen yimin Gong Haifeng Lv Jing Zhang yi yin Fangjia Li Changyong Lan Chun Li State Key Laboratory of Electronic Thin Films and Integrated Devices School of Optoelectronic Science and EngineeringUniversity of Electronic Science and Technology of ChinaChengduthe People's Republic of China School of Physics University of Electronic Science and Technology of ChinaChengduthe People's Republic of China Sichuan Academy of Medical Sciences and Sichuan People's Hospital Chengduthe People's Republic of China School of Medicine University of Electronic Science and Technology of ChinaChengduthe People's Republic of China

Two-dimensional transition metal dichalcogenides(TMDs)are needed in highperformance piezoresistive sensors due to their strong strain-induced bandgap modification and thereby large gauge factors.However,integrating a conventional high-temperature chemical vapor deposition(CVD)-grown TMD with a flexible substrate necessitates a transfer process that inevitably degrades the sensing properties of the TMDs and increases the overall fabrication complexity.We present a high-performance piezoresistive strain sensor that employs largearea PdSe_(2) films grown directly on polyimide(PI)substrates via plasma-assisted selenization of a sputtered Pd film.The reliable strain transfer from the substrate to the PdSe_(2) film ensures an outstanding strain-sensing capability of the sensor.Specifically,the sensors have a gauge factor of up to315±2.1,a response time under 25 ms,a detection limit of 8×10^(-6),and an exceptional stability of over 104 loadingunloading cycles.By attaching the sensors to the skin surface,we demonstrate their application for measuring physiological parameters in health care monitoring,including motion,voice,and arterial pulse vibration.Furthermore,using the PdSe_(2) film sensor combined with deep learning technology,we achieved intelligent recognition of artery temperature from arterial pulse signals with only a 2%difference between predicted and actual temperatures.The excellent sensing performance,together with the advantages of low-temperature fabrication and simple device structure,make the PdSe_(2) film sensor promising for wearable electronics and health care sensing systems.

关键词： layered crystal PdSe_(2) piezoresistive effect strain sensor

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Major and Trace Elements of Magnetite from the Qimantag Metallogenic Belt: Insights into Evolution of Ore–forming Fluids

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Acta Geologica Sinica(English Edition) 2015年第4期89卷 1226-1243页

作者： yi liwen GU Xiangping LU Anhuai LIU Jianping LEI Hao WANG Zhiling CUI Yu ZUO Hongyan SHEN Can Key Laboratory of Metallogenic Prediction of Nonferrous Metals and Geological Environment Monitor Ministry of Education School of Geosciences and Info–Physics Central South University

Magnetite, as a genetic indicator of ores, has been studied in various deposits in the world. In this paper, we present textural and compositional data of magnetite from the Qimantag metallogenic belt of the Kunlun Orogenic Belt in China, to provide a better understanding of the formation mechanism and genesis of the metallogenic belt and to shed light on analytical protocols for the in situ chemical analysis of magnetite. Magnetite samples from various occurrences, including the ore-related granitoid pluton, mineralised endoskarn and vein-type iron ores hosted in marine carbonate intruded by the pluton, were examined using scanning electron microscopy and analysed for major and trace elements using electron microprobe and laser ablation-inductively coupled plasma-mass spectrometry. The field and microscope observation reveals that early-stage magnetite from the Hutouya and Kendekeke deposits occurs as massive or banded assemblages, whereas late- stage magnetite is disseminated or scattered in the ores. Early-stage magnetite contains high contents of Ti, V, Ga, AI and low in Mg and Mn. In contrast, late-stage magnetite is high in Mg, Mn and low in Ti, V, Ga, AI. Most magnetite grains from the Qimantag metallogenic belt deposits except the Kendekeke deposit plot in the ＂ Skarn ＂ field in the Ca＋AI＋Mn vs Ti＋V diagram, far from typical magmatic Fe deposits such as the Damiao and Panzhihua deposits. According to the （MgO＋MnO）- TiO^-AI203 diagram, magnetite grains from the Kaerqueka and Galingge deposits and the No.7 ore body of the Hutouya deposit show typical characteristics of skarn magnetite, whereas magnetite grains from the Kendekeke deposit and the No.2 ore body of the Hutouya deposit show continuous elemental variation from magmatic type to skarn type. This compositional contrast indicates that chemical composition of magnetite is largely controlled by the compositions of magmatic fluids and host rocks of the ores that have reacted with the fluids. Moreover, a combination of petrography and magnetite geochemis

关键词： Magnetite trace element LA-ICP-MS ore genesis Qimantag metallogenic belt

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The Genesis Mechanism of the Mantle Fluid Action and Evolution in the Ore-Forming Process: A Case Study of the Laowangzhai Gold Deposit in Yunnan, China

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Acta Geologica Sinica(English Edition) 2012年第3期86卷 608-618页

作者： LIU Xianfan LI Chunhui LU Qiuxia DENG Biping SONG Xiangfeng ZHAO Fufeng CHU Yating XIAO Jixiong yi liwen HUANG Yupeng Institute of Earth Science Chengdu University of TechnologyChengdu 610059China State Key Laboratories for Mineral Deposits Research Nanjing UniversityNanjing 210093China

Based on petrological studies of the wall rocks, mineralizing rocks, ores and veins from the Laowangzhai gold deposit, it is discovered that along with the development of silication, carbonation and sulfidation, a kind of black opaque ultra-microlite material runs through the spaces between grains, fissures and cleavages. Under observations of the electron microprobe, scanning electronic microscopy and energy spectrum, this kind of ultra-microlite material is confirmed to consist of ultra microcrystalline quartz, silicate, sulfides and carbonates, as well as rutile, scheelite and specularite （magnetite）, showing characters of liquation by the analyses of SEM and energy spectrum. The coexistence of immiscibility and precipitating co-crystallization strongly suggests that the mineralizing fluid changed from the melt to the hydrothermal fluid. Combined with the element geochemical researches, it is realized that the ultra-microlite aggregate is the direct relics of the mantle fluid behaving like a melt and supercritical fluid, which goes along with the mantle-derived magma and will escape from the magma body at a proper time. During the alteration process, the nature of the mantle fluid changed and it is mixed with the crustal fluid, which are favorable for mineralization in the Loawangzhai gold deposit.

关键词： micro-petrography black opaque material ultra-microlite aggregate mantle fluid process and evolution the Laowangzhai gold deposit

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Odorant-binding protein 19 in Monochamus alternatus involved in the recognition of a volatile strongly emitted from ovipositing host pines

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Insect Science 2024年第1期31卷 134-146页

作者： Ruinan Yang Dongzhen Li Shancheng yi yi Wei Manqun Wang Hubei Insect Resources Utilization and Sustainable Pest Management Key Laboratory College of Plant Science and TechnologyHuazhong Agricultural UniversityWuhanChina Key Laboratory of Forest Protection of National Forestry and Grassland Administration Ecology and Nature Conservation InstituteChinese Academy of ForestryBeijingChina

Monochamus alternatus is the primary carrier of pine wood nematodes,which pose a serious threat to Pinus spp.in many countries.Newly emerging M.alternatus adults feed on heathy host pines,while matured adults transfer to stressed host pines for mating and oviposition.Several odorant-binding proteins(OBPs)of M.alternatus have been proved to aid in the complex process of host location.To clarify the corresponding relations between OBPs and pine volatiles,more OBPs need to be studied.In this research,MaltOBP19 showed a specific expression in the antennae and mouthparts of M.alternatus,and it was marked in 4 types of antenna sensilla by immunolocalization.Fluorescence binding assays demonstrated the high binding affinity of MaltOBP19 with camphene and myrcene in vitro.In Y-tube olfactory experiments,M.alternatus adults were attracted by camphene and RNAi of OBP19 via microinjection significantly decreased their attraction index.Myrcene induced phobotaxis,but RNAi had no significant effect on this behavior.Further,we found that ingesting dsOBP19 produced by a bacteria-expressed system with a newly constructed vector could lead to the knockdown of MaltOBP19.These results suggest that MaltOBP19 may play a role in the process of host conversion via the recognition of camphene,which has been identified to be strongly released in stressed host pines.In addition,it is proved that knockdown of OBP can be achieved by oral administration of bacteria-expressed double-stranded RNA in M.alternatus adults,providing a new perspective in the control of M.alternatus.

关键词： bacteria-expressed dsRNA camphene Japanese pine sawyer beetle MaltOBP19 RNAi stressed host pines

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Regulation of rhizosphere microenvironment by rice husk ash for reducing the accumulation of cadmium and arsenic in rice

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Journal of Environmental Sciences 2024年第2期136卷 1-10页

作者： yi Jiang Ya Liu Xuantao yi Peng Zeng Bohan Liao Hang Zhou Jiaofeng Gu College of Environmental Science and Engineering Central South University of Forestry and TechnologyChangsha 410004China Hunan Engineering Laboratory for Control of Rice Quality and Safety Changsha 410004China

It is important to reduce Cd and As content in brown rice in contaminated paddy soils.We conducted research on the effects of rice husk ash (RHA) on the Cd and As in the rhizosphere microenvironment (soil,porewater,and iron plaque) and measured the Cd,As,and Si content in rice plants.The main elements in RHA were Si (29.64%) and O (69.17%),which had the maximum adsorption capacity for Cd was 42.49 mg/kg and for As was 18.62 mg/kg.Soil pH and available Si content increased,while soil available Cd and As decreased following application of 0.5%–2%RHA.RHA promote the transformation of Cd to insoluble fraction,while As was transformed from a poorly soluble form to a more active one.RHA reduced Cd content and increased Si content in porewater,and reduced As only at the later rice growth stages.RHA increased the amount of iron plaque,thereby decreasing the Cd content in iron plaque,while increased the As content in it.Cd and inorganic As content in brown rice were decreased,to 0.31 mg/kg and 0.18 mg/kg,respectively.The decrease of Cd in brown rice was due to the decrease of Cd mobility in soil,thereby reducing root accumulation,while the decrease of As in brown rice was affected by the transport from roots to stems.Therefore,RHA can be considered as a safe and efficient in-situ remediation amendment for Cd and As co-contaminated paddy soil.

关键词： Rice husk ash(rha) Cadmium Arsenic Silicon Rice Soil

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NADPH oxidase 4(NOX4)as a biomarker and therapeutic target in neurodegenerative diseases

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Neural Regeneration Research 2024年第9期19卷 1961-1966页

作者： Napissara Boonpraman Sun Shin yi BK21 four Program Department of Medical SciencesSoonchunhyang UniversityAsanSouth Korea Department of Biomedical Laboratory Science Soonchunhyang UniversityAsanSouth Korea iConnectome Co.Ltd.CheonanSouth Korea

Diseases like Alzheimer’s and Parkinson’s diseases are defined by inflammation and the damage neurons undergo due to oxidative stress. A primary reactive oxygen species contributor in the central nervous system, NADPH oxidase 4, is viewed as a potential therapeutic touchstone and indicative marker for these ailments. This in-depth review brings to light distinct features of NADPH oxidase 4, responsible for generating superoxide and hydrogen peroxide, emphasizing its pivotal role in activating glial cells, inciting inflammation, and disturbing neuronal functions. Significantly, malfunctioning astrocytes, forming the majority in the central nervous system, play a part in advancing neurodegenerative diseases, due to their reactive oxygen species and inflammatory factor secretion. Our study reveals that aiming at NADPH oxidase 4 within astrocytes could be a viable treatment pathway to reduce oxidative damage and halt neurodegenerative processes. Adjusting NADPH oxidase 4 activity might influence the neuroinflammatory cytokine levels, including myeloperoxidase and osteopontin, offering better prospects for conditions like Alzheimer’s disease and Parkinson’s disease. This review sheds light on the role of NADPH oxidase 4 in neural degeneration, emphasizing its drug target potential, and paving the path for novel treatment approaches to combat these severe conditions.

关键词： Alzheimer’s disease astrocytes mitochondrial dysfunction myeloperoxidase NADPH oxidase 4 NADPH oxidase 4 inhibitors neurodegenerative diseases osteopontin Parkinson’s disease reactive oxygen species

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Dysfunction of synaptic endocytic trafficking in Parkinson's disease

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Neural Regeneration Research 2024年第12期19卷 2649-2660页

作者： Xin yi Ng Mian Cao Programme in Neuroscience and Behavioural Disorders Duke-NUS Medical SchoolSingaporeSingapore Department of Physiology National University of SingaporeSingaporeSingapore

Parkinson's disease is characterized by the selective degeneration of dopamine neurons in the nigrostriatal pathway and dopamine deficiency in the striatum.The precise reasons behind the specific degeneration of these dopamine neurons remain largely elusive.Genetic investigations have identified over 20 causative PARK genes and 90 genomic risk loci associated with both familial and sporadic Parkinson's disease.Notably,several of these genes are linked to the synaptic vesicle recycling process,particularly the clathrinmediated endocytosis pathway.This suggests that impaired synaptic vesicle recycling might represent an early feature of Parkinson's disease,followed by axonal degeneration and the eventual loss of dopamine cell bodies in the midbrain via a"dying back"mechanism.Recently,several new animal and cellular models with Parkinson's disease-linked mutations affecting the endocytic pathway have been created and extensively characterized.These models faithfully recapitulate certain Parkinson's disease-like features at the animal,circuit,and cellular levels,and exhibit defects in synaptic membrane trafficking,further supporting the findings from human genetics and clinical studies.In this review,we will first summarize the cellular and molecular findings from the models of two Parkinson's disease-linked clathrin uncoating proteins:auxilin(DNAJC6/PARK19)and synaptojanin 1(SYNJ1/PARK20).The mouse models carrying these two PARK gene mutations phenocopy each other with specific dopamine terminal pathology and display a potent synergistic effect.Subsequently,we will delve into the involvement of several clathrin-mediated endocytosis-related proteins(GAK,endophilin A1,SAC2/INPP5 F,synaptotagmin-11),identified as Parkinson's disease risk factors through genome-wide association studies,in Parkinson's disease pathogenesis.We will also explore the direct or indirect roles of some common Parkinson's disease-linked proteins(alpha-synuclein(PARK1/4),Parkin(PARK2),and LRRK2(PARK8))in synaptic endocytic trafficking.Additionall

关键词： autophagy auxilin/PARK19 clathrin-mediated endocytosis dopamine neurons neurodegeneration nigrostriatal pathway Parkinson's disease synaptic vesicle recycling synaptojanin1/PARK20

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