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Formation mechanisms and sequence response of authigenic grain-coating chlorite: evidence from the Upper Triassic Xujiahe Formation in the southern Sichuan Basin, China

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Petroleum Science 2016年第4期13卷 657-668页

作者： yu yu liang-Biao lin Jian Gao State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation Chengdu University of Technology Institute of Sedimentary Geology Chengdu University of Technology

Authigenic grain-coating chlorite is widely distributed in the clastic rocks of many sedimentary basins around the world. These iron minerals were mainly derived from flocculent precipitates formed when rivers flow into the ocean, especially in deltaic environments with high hydrodynamic conditions. At the same time, sandstone sequences with grain-coating chlorites also tend to have relatively high glauconite and pyrite content. EPMA composition analysis shows that glauconites with ‘‘high Al and low Fe’’ content indicate slightly to semi-saline marine environments with weak alkaline and weakly reducing conditions. By analyzing the chlorite-containing sandstone bodies of the southern Sichuan Xujiahe Formation, this study found that chlorite was mainly distributed in sedimentary microfacies, including underwater distributary channels, distributary channels, shallow lake sandstone dams, and mouth bars. Chlorite had a tendency to form in the upper parts of sandstone bodies with signs of increased base level, representing the influence of marine（lacustrine）transgression. This is believed to be influenced by megamonsoons in the Middle and Upper Yangtze Region during the Late Triassic Epoch. During periods of abundant precipitation, river discharges increased and more Fe particulates flowed into the ocean（lake）. In the meantime,increases or decreases in lake level were only affected byprecipitation for short periods of time. The sedimentary environment shifted from weakly oxidizing to weak alkaline, weakly reducing conditions as sea level increased, and Fe-rich minerals as authigenic chlorite and glauconite began to form and deposit.

关键词： Sichuan Basin Xujiahe Formation Graincoating chlorite Glauconite Pyrite

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Heat Transfer Characteristics of a Microchannel Heat Sink with Highly-Dense Micro-Jet Arrays

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Journal of Thermal Science 2024年第3期33卷 1148-1160页

作者： ZHANG yu CHEN Xiaoyan MIAO lin CHEN liang HOU yu State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049China Beijing Aerospace Technology Institute Beijing100083China

This paper proposed a new structure of highly-dense micro-jet arrays for hybrid jet-impingement/microchannel heat sinks(~120 jet per cm^(2) with jet width of 0.35 mm).Parametric study is performed to investigate the influence of structure and flow parameters on the convective heat transfer of water jet cooling in confined *** simulation results show that the optimal jet width,jet spacing and impingement distance are around 0.2 mm,0.2 mm and 0.3 mm,respectively,which can achieve a low thermal resistance as well as a relatively low pressure *** analysis of the heat transfer pathways shows that the micro-fin jet structures can extend the impinging heat transfer area and conduct a considerable proportion of heat,which can reach up to 38.9%with the Reynolds number ranging from 797.1 to *** heat transfer characteristics in the heat sink will shift from impingement dominated heat transfer to the channel-convection dominated heat transfer as the jet impingement distance increases.A correlation is proposed to predict the average Nusselt number on the stagnation area for the heat sink with different structure parameters,and the deviations of predictions from the numerical results are less than 10%.

关键词： hybrid heat sink impingement microchannel thermal management high heat flux

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Synthesis of chiral phosphine derivatives through a copper（I）-catalyzed desymmetric SNAr reaction

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Science China Chemistry 2025年

作者： Shuai Zhang Pei-Zhi Liu Yan-Bo Li Qi Zhang Jun-Zhao Xiao Yi-Fan Wang Tian-yu Wei Jia-Wei Jiang Ye Wang Qian Peng liang Yin Key Laboratory of Fluorine and Nitrogen Chemistry and Advanced Materials Shanghai Institute of Organic Chemistry University of Chinese Academy of Sciences Chinese Academy of Sciences State Key Laboratory of Elemento-Organic Chemistry and Tianjin Key Laboratory of Biosensing and Molecular Recognition College of Chemistry Frontiers Science Center for New Organic Matter Nankai University Haihe Laboratory of Sustainable Chemical Transformations

Axially chiral phosphines are a class of extremely important ligands in asymmetric catalysis. Herein, an unprecedented copper（I）-catalyzed asymmetric SNAr reaction with HP（S）R2is uncovered, which delivers a series of axially chiral phosphine derivatives in high yields with excellent enantioselectivity. Furthermore, the diastereoselective reaction with the kinetic resolution of racemic HP（S）ArR proceeds smoothly, providing the products with moderate diastereoselectivity and excellent enantioselectivity. Control experiments indicate that HP（S）Ph2is much more active than HPPh2and HP（O）Ph2as the pronucleophile in the present reaction. It is found that the SNAr reaction （the first SNAr） proceeds in a desymmetric manner, providing the desired chiral products while a continued SNAr reaction （the second SNAr） slightly occurs in a kinetic resolution manner in the present catalytic system, which enhances the ee of the desired chiral products. DFTcalculations support a concerted reaction pathway rather than a step-wise mechanism. Finally, axially chiral olefin-phosphines produced by the present method work as suitable ligands in Pdcatalyzed asymmetric allylic substitution with C-, N-, and O-nucleophiles and Rh-catalyzed asymmetric addition of arylboronic acid to benzil.

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Coseismic surface ruptures of MW7.8 and MW7.5 earthquakes occurred on February 6, 2023, and seismic hazard assessment of the East Anatolian Fault Zone, Southeastern Türkiye

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Science China Earth Sciences 2025年

作者： Peng liang yueren XU Xiaocheng ZHOU Ying LI Qinjian TIAN Huiping ZHANG Zhikun REN Jingxing yu Chuanyou LI Zheng GONG Shiguang WANG Aixia DOU Zifa MA Junjie LI Key Laboratory of Earthquake Prediction Institute of Earthquake ForecastingChina Earthquake Administration China Earthquake Disaster Prevention Center State Key Laboratory of Earthquake Dynamics Institute of GeologyChina Earthquake Administration Institute of Geophysics China Earthquake Administration

On February 6, 2023, southeastern Türkiye experienced a devastating earthquake doublet along the East Anatolian Fault（EAF）, with moment magnitude（MW） values of 7.8 and 7.5. These strong earthquakes resulted in at least 50,000 deaths and severe economic losses. Systematic research on coseismic surface ruptures induced by these events is vital for assessing the cascade rupture behaviors of plate boundary faults and future seismic hazards in the region. Interpretation of high-resolution post-earthquake satellite images and field investigations yielded the following results:（1） the two strong earthquakes had separate rupture zones. The first earthquake generated an approximately 280 km coseismic surface rupture along the southwestern segment of the main EAF, with 241 left-lateral displacements reaching up to 6.8±0.68 m, particularly 40 km northeast of the epicenter. The second earthquake produced a roughly 110 km surface rupture on an east-west branch of the EAF, with maximum displacements of 7.2±0.72 m.（2） The MW7.8 earthquake resulted in a cascading rupture across multiple segments of the southwestern section of the main EAF, with significantly variable displacements. The northeastern and southwestern parts of the main EAF and Malatya Fault remain at risk of strong earthquakes in the future.（3） The EAF rupture zone is densely populated, and due to the site amplification effect of loose sediments on foreland alluvial fans, foundation failures of buildings in the populated areas are common. Therefore, it is crucial to enhance the future seismic fortification capabilities in urban and rural areas along the EAF.

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绵羊IGF-Ⅰ和IGF-Ⅰ R基因特征分析及其在肌肉组织中的表达差异

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甘肃农业大学学报 2015年第2期50卷 6-15页

作者：王冬李发弟王维民马友记李冲梁育林甘肃农业大学动物科学与技术学院甘肃兰州730000 甘肃省肉羊繁育生物技术工程实验室甘肃民勤733300 甘肃省畜牧技术推广站甘肃天祝733200

为了比较IGF-Ⅰ和IGF-ⅠR基因在绵羊肌肉中的表达差异,根据GenBank公布的绵羊IGF-Ⅰ和IGF-ⅠR基因mRNA序列设计特异性引物,采用实时定量PCR方法检测其在甘肃‘高山细毛羊’及其与南非肉用‘美利奴’杂交F1代（南甘F1代）羔羊肌肉组织中... 详细信息

为了比较IGF-Ⅰ和IGF-ⅠR基因在绵羊肌肉中的表达差异,根据GenBank公布的绵羊IGF-Ⅰ和IGF-ⅠR基因mRNA序列设计特异性引物,采用实时定量PCR方法检测其在甘肃‘高山细毛羊’及其与南非肉用‘美利奴’杂交F1代（南甘F1代）羔羊肌肉组织中的表达量.利用生物信息学软件分析了绵羊IGF-Ⅰ和IGF-ⅠR基因结构,并构建系统进化树,探讨了其生物学功能.结果表明：南甘F1代羔羊肌肉组织中IGF-Ⅰ基因的表达量显著高于‘甘肃高山细毛羊’（P〈0.05）,而IGF-ⅠR基因的表达量在南甘F1代羔羊和‘甘肃高山细毛羊’肌肉组织中没有显著变化（P〉0.05）.绵羊IGF-Ⅰ和IGF-ⅠR基因分别含有465bp和4 518bp的完整开放阅读框,编码154个和1 505个氨基酸;其蛋白质分子量分别为17 011.71U和169 267.26U,等电点分别为9.36和6.70;IGF-Ⅰ基因信号肽切割点分别位于49～50位氨基酸之间,而IGF-ⅠR基因不含信号肽;IGF-Ⅰ基因编码产物的二级结构主要以无规则卷曲和α-螺旋为主,位于细胞核的可能性最高（62.5%）;IGF-ⅠR基因编码产物的二级结构主要以无规则卷曲为主,位于细胞质的可能性最高（34.8%）;IGF-Ⅰ和IGF-ⅠR基因分别作为激素和信号传感器参与机体生物学过程.

关键词：绵羊 IGF-Ⅰ基因 IGF-ⅠR基因生物信息学分析 RT-qPCR

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敦煌三危山出产多色颜料的矿物学及谱学特征研究

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光谱学与光谱分析 2025年第1期45卷 152-159页

作者：李林筱谭宇辰先怡衡铁付德孙满利艾昊梁云孙凤西北大学文化遗产学院陕西西安710127 中国国家博物馆北京100006

敦煌三危山火焰沟发现一处古代多色颜料开采遗址,该遗址的发现对研究我国西北地区古代矿物颜料的来源有着一定的学术意义。为判断三危山出产颜料的矿物种属及其谱学特征,本文应用偏光显微镜、X射线衍射、激光拉曼光谱、X射线荧光光谱多... 详细信息

敦煌三危山火焰沟发现一处古代多色颜料开采遗址,该遗址的发现对研究我国西北地区古代矿物颜料的来源有着一定的学术意义。为判断三危山出产颜料的矿物种属及其谱学特征,本文应用偏光显微镜、X射线衍射、激光拉曼光谱、X射线荧光光谱多种光谱分析手段对所出产多色颜料矿物开展科学分析。结果表明,三危山古矿出产矿物颜料属天然矿物,主要化学成分为Fe_(2)O_(3)(平均含量66%)和SiO_(2)等,部分样品呈现富硅铝的特征,且均存在不同程度的烧失;主要物相以赤铁矿、针铁矿为主,少许铁矾类,脉石矿物包括石英、高岭石及少许黏土矿物。同时进一步通过拉曼光谱对矿物颜料的显色物相进行分析,2号亮黄色矿物显色物相和前述主要物相一致,均为铁矾类(黄钾铁矾和黄钠铁矾)。除4号样品外,所有呈红棕色的样品主要显色物相均为α-Fe_(2)O_(3)即赤铁矿,而4号样品显色物相为针铁矿,呈色本应为黄色,但致其呈色变为红棕色是由于和赤铁矿伴生存在,且赤铁矿显色能力远强于针铁矿,故改变了4号样品的呈色。综上,该古矿遗址所出产的红色矿物颜料主要为赤铁矿,黄色矿物颜料为黄钾铁矾和黄钠铁矾。黄钾铁矾作为优良的颜料,在岩画及壁画也多有使用,但在莫高窟目前已研究的壁画上暂未发现使用,三危山古矿实证了铁矾类颜料矿物的存在,该发现在一定程度上拓宽了对西北地区黄色矿物颜料的维度。同时也为后续研究该矿冶遗址出产颜料的流向,提供了基础性的数据支撑。

关键词：敦煌采矿遗址矿物颜料呈色拉曼光谱

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Altered 3D genome reorganization mediates precocious myeloid differentiation of aged hematopoietic stem cells in inflammation

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Science China Life Sciences 2025年

作者： Xinyu Cui yu Dong Qiang Zhan Yixin Huang Qianshu Zhu Zihao Zhang Guang Yang Liping Wang Shijun Shen Jia Zhao Zhiyi lin Jiatong Sun Zhongqu Su Yihan Xiao Chuyu Zhang yuwei liang Lu Shen Lichen Ji Xuguang Zhang Jiqing Yin Hong Wang Zhiyang Chen Zhenyu Ju Cizhong Jiang Rongrong Le Shaorong Gao Clinical and Translational Research Center of Shanghai First Maternity & Infant Hospital Frontier Science Center for Stem Cells School of Life Sciences and Technology Tongji University Key Laboratory of Spine and Spinal Cord Injury Repair and Regeneration of Ministry of Education Orthopaedic Department of Tongji Hospital School of Life Sciences and Technology Tongji University Key Laboratory of Regenerative Medicine of Ministry of Education Institute of Aging and Regenerative Medicine Department of Developmental & Regenerative Medicine College of Life Science and Technology Jinan University Shandong Key Laboratory of Animal Bioengineering and Disease Prevention College of Animal Science and Technology Shandong Agricultural University Department of Joint Surgery Shanghai East Hospital Tongji University School of Medicine Shanghai Institute of Nutrition and Health Chinese Academy of Sciences

Inflammation is a driving force of hematopoietic stem cells(HSCs) aging, causing irreversible exhaustion of functional HSCs. However, the underlying mechanism of HSCs erosion by inflammatory insult remains poorly understood. Here, we find that transient LPS exposure primes aged HSCs to undergo accelerated differentiation at the expense of self-renewal, leading to depletion of HSCs. Meanwhile, the central regulator nuclear factor kappa B(NF-κB) mediating functional impairment by inflammation insult induces differential transcriptional response in aged HSCs compared with young HSCs, with precocious activation of myeloid lineage genes. Altered compartmentalization and chromatin loop formation are associated with aging-related differential transcriptional response in HSCs upon lipopolysaccharide(LPS)stimulation. Mechanistically, enhancer and promoter regions of myeloid lineage genes in aged HSCs are more accessible and display more rapid and prominent CTCF occupancy upon LPS stimulation. Our study provides comprehensive resources for the three-dimensional(3D)genome structure of HSCs and sheds light into the ordered genome organization and the associated transcriptome signature underlying HSCs aging.

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穿透性角膜移植术后新生血管的治疗进展

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医学综述 2013年第20期19卷 3711-3714页

作者：梁毓琳李云川杨文艳李兰昆明市第一人民医院眼科昆明650034

角膜新生血管不但严重影响视力,而且导致角膜移植手术的失败。近年来,国内外对穿透性角膜移植术后新生血管的药物治疗取得迅猛发展,抗血管内皮细胞生长因子药物临床应用效果显著,也可行激光治疗仪激光、基因、高压氧及手术等治疗。但角... 详细信息

角膜新生血管不但严重影响视力,而且导致角膜移植手术的失败。近年来,国内外对穿透性角膜移植术后新生血管的药物治疗取得迅猛发展,抗血管内皮细胞生长因子药物临床应用效果显著,也可行激光治疗仪激光、基因、高压氧及手术等治疗。但角膜新生血管依然是目前最常见的致盲原因之一,制订个体化的治疗方案、采用最有效的给药方式及剂量等是今后研究的重点。

关键词：穿透性角膜移植术角膜新生血管治疗进展

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小茴香挥发油热稳定性研究及其抗氧化剂筛选

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中华中医药杂志 2019年第11期34卷 5379-5383页

作者：邰佳邹俊波史亚军张小飞王瑜梁玉琳李婧琳王晶程江雪赵重博王媚陕西中医药大学药学院陕西省中药基础与新药研究重点实验室

目的:探索小茴香挥发油成分热稳定性变化规律,并优选最佳抗氧化剂种类。方法:采用水蒸气蒸馏法提取小茴香挥发油,通过气相色谱-质谱(GC-MS)分析小茴香挥发油加热前后化学成分,筛选使挥发油成分变化最剧烈的加热温度及时间。另取7种不同... 详细信息

目的:探索小茴香挥发油成分热稳定性变化规律,并优选最佳抗氧化剂种类。方法:采用水蒸气蒸馏法提取小茴香挥发油,通过气相色谱-质谱(GC-MS)分析小茴香挥发油加热前后化学成分,筛选使挥发油成分变化最剧烈的加热温度及时间。另取7种不同抗氧化剂,于筛选的温度及时间下干预小茴香挥发油,优选对小茴香挥发油稳定性改善最明显的抗氧化剂种类。结果:本次实验共测得小茴香挥发油成分46个,热图结合特征成分变化率图结果显示加热温度为100℃且加热时间为8h时小茴香挥发油成分变化最剧烈,麝香草酚改善小茴香挥发油稳定性效果最佳。结论:小茴香挥发油成分受温度影响变化明显。抗氧化剂可有效抑制小茴香挥发油热氧化趋势,为挥发油氧化稳定性改善研究提供了参考。

关键词：小茴香挥发油热稳定性抗氧化剂气相色谱-质谱

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Improving phase transition temperature of VO_(2) via Ge doping:a combined experimental and theoretical study

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Rare Metals 2021年第5期40卷 1337-1346页

作者： lin Wang yu-Qi Hao Wei Ma Sen liang Ningxia Key Laboratory of Photovoltaic Materials Ningxia UniversityYinchuan 750021China

Enhancing the semiconductor-metal phase transition temperature(TSMT)of VO_(2) is of great consequence for further exploring the potential applications of VO_(2) at elevated *** this study,Ge^(4+)-doped VO_(2)(Ge_(x)V_(1-x)O_(2))samples were prepared by the hydrothermal and annealing approach.X-ray diffraction(XRD),high-resolution transmission electron microscopy(HRTEM),differential scanning calorimetry(DSC)and resistivity-temperature(R-T)analyses were used to investigate the influence of Ge doping on the lattice structures and phase transition properties of Ge_(x)V_(1-x)O_(2) *** found that the lattice parameter of Ge_(x)V_(1-x)O_(2) decreased with the Ge concentration increasing from 2 at%to 18 at%,which was further supported by density functional theory(DFT)-based first-principle *** firstly increased from 64.5 to 73.0℃ at 8 at% Ge and then decreased to 71.5℃ at higher Ge ***,DFT analysis revealed that the impact of lattice distortion induced by Ge doping rather than the changes in electronic structure is more pronounced on modulating TSMT of Ge_(x)V_(1-x)O_(2).The present work has pointed out the direction that the TSMT could be enhanced and illustrated the physical reason behind the regulation of TSMT in ionsdoped VO_(2) systems.

关键词： Vanadium dioxide Phase transition temperature Germanium doping Lattice distortion

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