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云南墨江金矿区内凝灰岩的成因及对金成矿作用的意义

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岩石学报 2024年第8期40卷 2503-2518页

作者：郭娜欣刘善宝李万平王成辉赵晨辉中国地质科学院矿产资源研究所自然资源部成矿作用与资源评价重点实验室北京100037 墨江县矿业有限责任公司普洱654899

云南墨江金厂金矿是哀牢山金矿带内的一个大型金矿床,矿床受剪切带控制,矿体赋存于古生代浅变质岩中,其成矿物质来源一直是争论的焦点。为进一步精确约束赋矿地层的形成时代和大地构造背景,探讨其与金成矿物质来源和成矿作用之间的关系... 详细信息

云南墨江金厂金矿是哀牢山金矿带内的一个大型金矿床,矿床受剪切带控制,矿体赋存于古生代浅变质岩中,其成矿物质来源一直是争论的焦点。为进一步精确约束赋矿地层的形成时代和大地构造背景,探讨其与金成矿物质来源和成矿作用之间的关系,本文对古生代浅变质岩中的凝灰岩开展了年代学、地球化学、黄铁矿成分和同位素特征研究。LA-ICP-MS锆石U-Pb定年结果(256.6±2.3Ma)表明墨江金矿区内存在晚二叠世火山碎屑岩。锆石稀土元素含量较高,Ce正异常(δCe=2.02~32.98)和Eu负异常明显(δEu=0.06~0.38)。岩石具有低钛(TiO_(2)=0.47%~0.71%)、较高铝(Al_(2)O_(3)=10.96%~16.33%)、富铁(Fe_(2)O_(3)T=3.21%~9.12%)和硫(S=0.95%~3.92%)等特征,属于英安质-流纹质凝灰岩;此外,所有样品轻重稀土元素分馏显著((La/Yb)_(N)=7.50~15.7),Eu异常明显(δEu=0.54~0.68),亏损Nb、Ta、Ti、Sr、Ba,富集K、Pb,显示出弧火山岩的地球化学特征。Nd同位素(ε_(Nd)=-9.24~-9.61)显示富集特征,二阶段钕模式年龄为1.61~1.79ga。凝灰岩中富含黄铁矿,黄铁矿属铁亏损型(S/Fe=2.00~2.09),存在ni对Fe、As对S的类质同象置换;S主要来自地壳(δ^(34)SV-CDT=-8.8‰~-9.7‰);Co、ni含量高但没有相关性,指示其为火山成因,后期受到了富ni流体交代;黄铁矿的Au含量偏高,但未发现独立金矿物,推测可能存在纳米金。全岩地球化学特征、Nd同位素特征和锆石微量元素特征指示墨江金矿区凝灰岩形成于陆缘弧构造背景,为古特提斯洋俯冲消减过程中玄武质岩浆底侵导致古元古代变质基底重熔的产物,岩浆形成过程中伴有地幔物质的加入,同时存在金的初始富集,形成含金黄铁矿,并在随后的区域变质作用及构造热事件中发生金的活化迁移,为金矿床的最终形成提供成矿物质。晚二叠世弧岩浆作用对于墨江金矿的形成具有重要意义。

关键词：凝灰岩晚二叠世陆缘弧墨江金矿区哀牢山金矿带

Cytotoxicity and binding profiles of activated CrylAc and Cry2Ab to three insect cell lines

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Insect Science 2018年第4期25卷 655-666页

作者： Jizhen Wei Gemei Liang Kongming Wu Shaohua Gu Yuyuan guo Xinzhi ni Xianchun Li State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing China Department of Entomology and BIO5 Institute University of Arizona Tucson AZ USA USDA-ARS Crop Genetics and Breeding Research Unit Tifton GA USA

While CrylAc has been known to bind with larval midgut proteins cad- herin, APN （amino peptidase N）, ALP （alkaline phosphatase） and ABCC2 （adenosine triphosphate-binding cassette transporter subfamily C2）, little is known about the recep- tors of Cry2Ab. To provide a clue to the receptors of Cry2Ab, we tested the baseline cytotoxicity of activated Cry 1Ac and Cry2Ab against the midgut and fat body cell lines of Helicoverpa zea and the ovary cell line ofSpodopterafrugiperda （SFg）. As expected, the descending order of cytotoxicity of CrylAc against the three cell lines in terms of 50% lethal concetration （LC50） was midgut （31.0μg/mL）〉 fat body （59.0μg/mL） and SF9 cell （99.6μg/mL）. By contrast, the fat body cell line （LC50 = 7.55μg/mL） was about twice more susceptible to Cry2Ab than the midgut cell line （16.0/xg/mL）, the susceptibility of which was not significantly greater than that of SF9 cells （27.0μg/mL）. Further, ligand blot showed the binding differences between CrylAc and Cry2Ab in the three cell lines. These results indicated that the receptors of Cry2Ab were enriched in fat body cells and thus largely different from the receptors of CrylAc, which were enriched in midgut cells.

关键词： Bt cell toxicity receptors midgut cell fat body cell SF9 cell

Q420qENH钢及其焊接接头在模拟含PM_(2.5)的工业大气介质中干湿循环腐蚀行为研究

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表面技术 2024年第2期53卷 97-109页

作者：张利帅郭铁明武维宏胡焱文刘晓倩南雪丽周贵易易维斌兰州理工大学有色金属先进加工与再利用国家重点实验室兰州730050 甘肃省交通规划勘察设计院股份有限公司兰州730050 甘肃省精密加工技术及装备工程研究中心兰州730050

目的研究桥梁耐候钢板材及其焊接接头在模拟含PM_(2.5)的西北工业大气环境中腐蚀行为的区别。方法采用NaHSO_(3)+SiO_(2)的腐蚀介质进行干湿交替加速腐蚀实验,并采用腐蚀动力学、X射线衍射、扫描电镜+能谱、电化学测试等方法,分析了Q4... 详细信息

目的研究桥梁耐候钢板材及其焊接接头在模拟含PM_(2.5)的西北工业大气环境中腐蚀行为的区别。方法采用NaHSO_(3)+SiO_(2)的腐蚀介质进行干湿交替加速腐蚀实验,并采用腐蚀动力学、X射线衍射、扫描电镜+能谱、电化学测试等方法,分析了Q420qENH钢板材、焊缝及热影响区试样的腐蚀趋势、腐蚀类型及锈层的保护性,以及SiO_(2)对腐蚀的影响。结果 Q420qENH板材试样初期腐蚀速率大于焊接试样,中后期2种试样腐蚀速率逐渐下降并趋于一致。3种试样腐蚀类型均为不均匀的全面腐蚀,外锈层均疏松易脱落,但焊缝、热影响区内锈层比板材致密且与钢基体结合紧密,锈层中Cu、ni元素含量明显高于板材试样。3种试样腐蚀30d的自腐蚀电流密度由大到小的顺序为板材>焊缝>热影响区,自腐蚀电位由大到小的顺序为热影响区>焊缝>板材,焊缝及热影响区试样的锈层电阻分别为板材试样的1.28倍、1.68倍。结论 PM_(2.5)中的主要成分SiO_(2)易在缺陷处沉积,成为腐蚀产物的形核基底,促进了腐蚀产物的非均匀形核,不利于锈层的致密性。热影响区和焊缝形成锈层的保护性、耐蚀性能优于板材试样。

关键词： Q420qE桥梁耐候钢焊接接头西北工业大气环境 PM_(2.5) SiO_(2) 干湿循环腐蚀

Risk stratification of hemodynamically significant patent ductus arteriosus by clinical and genetic factors

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World Journal of Pediatrics 2023年第12期19卷 1192-1202页

作者： Yu-Xi Chen Tian-Tian Xiao Hui-Yao Chen Xiang Chen Ya-Qiong Wang Qi ni Bing-Bing Wu Hui-Jun Wang Yu-Lan Lu Li-Yuan Hu Yun Cao guo-qiang Cheng Lai-Shuan Wang Fei-Fan Xiao Lin Yang Xin-Ran Dong Wen-Hao Zhou Center for Molecular Medicine of Children’s Hospital of Fudan University Institutes of Biomedical SciencesFudan University138 Yi Xue Yuan RoadShanghaiChina Department of Neonatology Children’s Hospital of Fudan UniversityNational Children’s Medical CenterShanghaiChina Center for Molecular Medicine Children’s Hospital of Fudan University399 Wanyuan RoadShanghai201102China

Background Hemodynamically significant patent ductus arteriosus(hsPDA)is associated with increased comorbidities in *** evaluation of hsPDA risk is critical to implement individualized *** aim of the study was to provide a powerful reference for the early identification of high-risk hsPDA population and early treatment *** We enrolled infants who were diagnosed with PDA and performed exome *** collapsing analyses were used to find the risk gene set(RGS)of hsPDA for model *** credibility of RGS was proven by RNA *** logistic regression was performed to establish models combining clinical and genetic *** models were evaluated by area under the receiver operating curve(AUC)and decision curve analysis(DCA).Results In this retrospective cohort study of 2199 PDA patients,549(25.0%)infants were diagnosed with *** model[all clinical characteristics selected by least absolute shrinkage and selection operator regression(all CCs)]based on six clinical variables was acquired within three days of life,including gestational age(ga),respiratory distress syndrome(RDS),the lowest platelet count,invasive mechanical ventilation,and positive inotropic and vasoactive *** has an AUC of 0.790[95%confidence interval(CI)=0.749–0.832],while the simplified model(basic clinical characteristic model)including ga and RDS has an AUC of 0.753(95%CI=0.706–0.799).There was a certain consistency between RGS and differentially expressed genes of the ductus arteriosus in *** AUC of the models was improved by RGS,and the improvement was significant(all CCs *** CCs+RGS:0.790 vs.0.817,Pnically *** Models based on clinical factors were developed to accurately stratify the risk of hsPDA in the first three days of *** features might further improve the model performance.

关键词： Exome sequencing-Hemodynamically significant patent ductus arteriosus Multivariate logistic regression Neonates Risk stratification

Self-assembled semiconductor quantum dots decorating the facets of gaAs nanowire for single-photon emission

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National Science Review 2017年第2期4卷 196-209页

作者： Ying Yu guo-Wei Zha Xiang-Jun Shang Shuang Yang Ban-Quan Sun Hai-qiao ni Zhi-Chuan niu State Key laboratory for Superlattice and Microstructures Institute of SemiconductorsChinese Academy of Sciences State Key Laboratory of Optoelectronic Materials and Technologies School of electronics and information technologySun Yat-sen University College of Materials Science and Opto-Electronic Technology University of Chinese Academy of Sciences Synergetic Innovation Center of Quantum Information& Quantum Physics University of Science and Technology of China

In this chapter, we discuss the epitaxial growth of self-assembled quantum dots(QDs) in gaAs nanowires(NWs) and the characteristics of their single-photon emissions. We demonstrate ga droplet-induced gold-free vapor-liquid-solid growth of hexagonal gaAs/Al gaAs core–shell NWs, branched gaAs NWs and tailored nanostructured morphologies on the NW facets. Particularly, we show two new types of QD-in-NW systems: one is a single InAs QD formed at the corner of a branched gaAs NW, and the other is a single gaAs QD formed on the NW facet. Sharp excitonic emission spectral lines are observed with vanishing two-photon emission probability. Furthermore, a single gaAs QD is achieved at the site of a single Al gaAs quantum ring(QR) on the NW facet. In addition, these NW-based single QDs are in-situ probed and integrated with single-mode optical ibers to achieve all-iber-output single-photon sources for potential application in quantum integrated networks.

关键词： self-assembled nanowires quantum dots single photon emitters molecular beam epitaxy

A natural variation in Ribonuclease H-like gene underlies Rht8 to confer“Green Revolution”trait in wheat

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Molecular Plant 2022年第3期15卷 377-380页

作者： Lingling Chai Mingming Xin Chaoqun Dong Zhaoyan Chen Huijie Zhai Junhong Zhuang Xuejiao Cheng Naijiao Wang Jia Geng Xiaobo Wang Ruolin Bian Yingyin Yao Weilong guo Zhaorong Hu Huiru Peng Guihua Bai Qixin Sun Zhenqi Su Jie Liu Zhongfu ni State Key Laboratory for Agrobiotechnology and Key Laboratory of Crop Heterosis and Utilization(MOE)and Beijing Key Laboratory of Crop Genetic Improvement China Agricultural UniversityBeijingChina School of Life Science and Technology Henan Institute of Science and TechnologyXinxiangChina Center for Crop Functional Genomics and Molecular Breeding China Agricultural UniversityBeijingChina State Key Laboratory for Crop Genetics and Germplasm Enhancement Nanjing Agricultural UniversityNanjingChina USDA–ARS Hard Winter Wheat Genetics Research UnitManhattanKSUSA

Dear Editor,Introduction of gibberellin(ga)-insensitive Reduced height(Rht)genes,Rht-B1b and Rht-D1b,has resulted in the“Green Revolution”in modern wheat cultivars(Triticum aestivum)that has skyrocketed wheat grain yields worldwide since the 1960s(Peng et al.,1999;Velde et al.,2021).However,Rht-B1b/D1b also reduce coleoptiles,which is undesired in dryland regions where deep planting is essential for seedling establishment(Rebetzke et al.,1999,Rebetzke et al.,2001;Ellis et al.,2004).

关键词： aestivum seedling cultivar

Detrital Zircon of 4100 Ma in Quartzite in Burang,Tibet

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Acta Geologica Sinica(English Edition) 2006年第6期80卷 954-956页

作者： DUO Ji WEN Chunqi FAN Xiaoping guo Jianci ni Zhiyao LI Xiaowen SHI Yuruo WEN Quan Bureau of Geology and Mineral Resources of Tibet Autonomous Region Lhasa Tibet 850000 Chengdu University of Technology Chengdu Sichuan 610059 Beijing SHRIMP Center Beijing 100037

A detrital zircon aged 4.1 ga is discovered by the SHRIMP U-Pb method in a quartzite in Burang County, western Tibet. This is presently the oldest single-grain detrital zircon in China. The Th-U ratios of the two testing points of the 〉4.0 ga zircon are between 0.76 and 0.86, indicating their magmatic origin. This discovery has offered an important age for investigating the geological evolution of the Qinghai-Tibet Plateau.

关键词： SHRIMP detrital zircon 4.1 ga Tibet

镓状态对原位合成高硅ga-ZSM-5的甲醇制芳烃反应性能影响

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石油学报(石油加工) 2023年第6期39卷 1242-1250页

作者：倪婉萍刘民郭新闻大连理工大学化工学院PSU-DUT联合能源研究中心精细化工国家重点实验室辽宁大连116024

为解决ZSM-5催化剂上甲醇转化生成芳烃选择性较低的问题,采用乙二胺络合镓离子的方法原位合成了高硅ga-ZSM-5沸石催化剂。通过XRD、SEM、物理吸附-脱附、XPS、ICP等手段对其进行表征,并采用固定床反应器进行催化甲醇制芳烃反应性能评价... 详细信息

为解决ZSM-5催化剂上甲醇转化生成芳烃选择性较低的问题,采用乙二胺络合镓离子的方法原位合成了高硅ga-ZSM-5沸石催化剂。通过XRD、SEM、物理吸附-脱附、XPS、ICP等手段对其进行表征,并采用固定床反应器进行催化甲醇制芳烃反应性能评价。结果表明:原位合成引入ga对ZSM-5孔结构影响较小,对酸性质影响较大;催化剂表面的镓物种由相对摩尔分数为44%~56%的骨架ga、26%~34%的非骨架ga和少量游离态ga_(2)O_(3)组成;ga的引入显著提升了ZSM-5催化剂的甲醇芳构化反应活性和苯、甲苯选择性;在压力0.1 MPa、温度450℃、质量空速2 h^(-1)的条件下,ga质量分数0.5%制备的ga-ZSM-5催化剂在反应时间380 h内甲醇转化率均高于99.9%,具有高稳定性和高芳烃选择性,甲醇制芳烃反应催化性能最佳。

关键词： ga-ZSM-5催化剂甲醇芳烃原位合成芳构化反应骨架ga

New class of high-entropy pseudobrookite titanate with excellent thermal stability,low thermal expansion coefficient,and low thermal conductivity

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Journal of Advanced Ceramics 2022年第10期11卷 1654-1670页

作者： Jinyu WU Xiaohui MA Xiaoxia HU Liwen YAN Feng HOU Jiachen LIU Anran guo School of Materials Science and Engineering Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of EducationTianjin UniversityTianjin 300072China

As a type of titanate,the pseudobrookite(MTi_(2)O_(5)/M_(2)TiO_(5))exhibits a low thermal expansion coefficient and thermal conductivity,as well as excellent dielectric and solar spectrum absorption ***,the pseudobrookite is unstable and prone to decomposing below 1200℃,which limits the practical application of the *** this paper,the high-entropy pseudobrookite ceramic is synthesized for the first *** pure high-entropy(Mg,Co,ni,Zn)Ti_(2)O_(5) with the pseudobrookite structure and the biphasic high-entropy ceramic composed of the highentropy pseudobrookite(Cr,Mn,Fe,Al,ga)_(2)TiO_(5) and the high-entropy spinel(Cr,Mn,Fe,Al,ga,Ti)_(3)O_(4) are successfully prepared by the in-situ solid-phase reaction *** comparison between the theoretical crystal structure of the pseudobrookite and the aberration-corrected scanning transmission electron microscopy(AC-STEM)images of high-entropy(Mg,Co,ni,Zn)Ti_(2)O_(5) shows that the metal ions(M and Ti ions)are disorderly distributed at the A site and the B site in high-entropy(Mg,Co,ni,Zn)Ti_(2)O_(5),leading to an unprecedentedly high configurational entropy of high-entropy(Mg,Co,ni,Zn)Ti_(2)O_(5).The bulk high-entropy(Mg,Co,ni,Zn)Ti_(2)O_(5) ceramics exhibit a low thermal expansion coefficient of 6.35×10^(−6) K^(−1) in the temperature range of 25-1400℃ and thermal conductivity of 1.840 W·m^(−1)·K^(−1) at room temperature,as well as the excellent thermal stability at 200,600,and 1400℃.Owing to these outstanding properties,high-entropy(Mg,Co,ni,Zn)Ti_(2)O_(5) is expected to be the promising candidate for high-temperature thermal *** work has further extended the family of different crystal structures of high-entropy ceramics reported to date.

关键词： high-entropy pseudobrookite (Mg,Co,ni,Zn)Ti_(2)O_(5) (Cr,Mn,Fe,Al,ga)_(2)TiO_(5) high conformational entropy thermal expansion coefficient thermal conductivity