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Hybrid structure of iron single atoms and metallic titanium for photothermal ethanol steam reforming

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Science China Chemistry 2024年第3期67卷 848-854页

作者： Dachao Yuan Guanda han Zhixuan Wang Jianguo Zhao Kailuan Li Pengfei Wang jianjun Hao Yaguang Li Jinhua Ye College of Mechanical and Electrical Engineering Technology Innovation Center of Intelligent Agricultural EquipmentHebei Agricultural UniversityBaoding 071001China Research Center for Solar Driven Carbon Neutrality The College of Physics Science and TechnologyInstitute of Life Science and Green DevelopmentHebei UniversityBaoding 071002China International Center for Materials Nanoarchitectonics(WPI-MANA) National Institute for Materials Science(NIMS)1-1 NamikiTsukubaIbaraki 305-0044Japan Graduate School of Chemical Science and Engineering Hokkaido UniversitySapporo 060-0814Japan

Photothermal ethanol steam reforming(ESR) is currently limited by low intrinsic activity and strong solar energy dissipation.Herein,we synthesized Fe single atoms supported on CeO_(2)(SA Fe-CeO_(2)) to exhibit excellent low-temperature ESR activity with a hydrogen production rate of 512 mmol g^(-1)h^(-1) at 350℃,becuase of the high oxidation state of Fe single atoms to weaken the reaction barrier of ethanol decomposition.Furthermore,a heterostructure of SA Fe-CeO_(2) and Ti foil could eliminate 66% of infrared radiation via the size effect,thus achieving a 3.5 sun-driven temperature of 347℃.Consequently,the heterostructure of SA Fe-CeO_(2) and Ti foil shows a hydrogen generation rate of 984 mmol g^(-1)h^(-1) of ESR and 11.31% of solar-to-hydrogen energy conversion efficiency,which outperforms other photothermal ethanol-hydrogen production systems.This study provides a new path for designing active catalytic sites and trapping light energy of photothermal catalysts.

关键词： photothermal catalysis single atoms heterostructure ethanol steam reforming iron

Effect of Fe_(2)O_(3)on the Structure,Physical Properties and Crystallization of CaO-Al_(2)O_(3)-SiO_(2)Glass

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Journal of Wuhan University of Technology(Materials Science) 2024年第4期39卷 954-961页

作者：张峰 XIONG Dehua 谢俊张继红 han jianjun CHEN Dequan WEN Zhongquan FAN Zhenhua CHEN Lina SUN Tengfei State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China Hepu Research Center for Silicate Materials Industry Technology Beihai 536100China Hainan Institute of Wuhan University of Technology Sanya 430079China Shenzhen Research Institute of Wuhan University of Technology Shenzhen 518000China Chongqing Polycomp Inter-national Corporation Chongqing 400400China

The calcium aluminosilicate-based glasses(CaO-Al_(2)O_(3)-SiO_(2),CAS)with different Fe_(2)O_(3)content(0.10wt%,0.50wt%,0.90wt%,and 1.30wt%)were prepared by traditional melt-quenching method.The glass network structure,thermal and mechanical properties,and crystallization behavior changes were investigated by nuclear magnetic resonance spectrometer,Fourier-transform infrared spectro-photometer,X-ray diffractometer,differential scanning calorimetry and field emission scanning electron microscope measurements.The change of Q^(n)in glass structures reveals the glass network connectivity decreases due to the increasing content of Fe_(2)O_(3)addition,resulting in the increasing of non-bridging number in glass structure.The glass densities slightly rise from 2.644 to 2.681 g/cm^(3),while Vickers’s hardness increases at first,from 6.469 to 6.901 GPa,then slightly drops to 6.745 GPa,with Fe_(2)O_(3)content increase.There is almost no thermal expansion coefficient change from different Fe_(2)O_(3)content.The glass transmittance in visible range gradually decreases with higher Fe_(2)O_(3)content,resulting from the strong absorption of Fe^(2+)and Fe^(3+)ions.The calculated activation energy from thermal analysis results first decreases from 282.70 to 231.18 kJ/mol,and then increases to 244.02 kJ/mol,with the Fe_(2)O_(3)content increasing from 0.10wt%to 1.30wt%.Meanwhile,the maximum Avrami constant of 2.33 means the CAS glasses exhibit two-dimensional crystallization.All of the CAS glass-ceramics samples contain main crystal phase of anorthite,the microstructure appears lamellar and columnar crystals.

关键词： calcium aluminosilicate glass network structure physical properties crystallization

Linkage between riverbed scouring or deposition and the evolution of central bars:Case study in the Yangzhong reach of the Yangtze River

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Journal of Geographical Sciences 2024年第7期34卷 1323-1348页

作者： YANG Yunping ZhanG Xiabo FENG Xiaoxiang han Jianqiao WANG jianjun ZHU Yude YANG Yanhua Tianjin Research Institute for Water Transport Engineering Ministry of Transport College of Harbour Coastal and Offshore Engineering Hohai University Northwest Agriculture and Forestry University

Understanding the relationship between unbalanced riverbed scouring or deposition and the evolution of central bars in natural conditions and human activity is useful for river regime control and waterway improvement projects. Toward this end, we utilized the Yangzhong reach in the lower reaches of the Yangtze River as a case study and evaluated runoff,sediment content, and topographical data measured over the past 70 years（1951–2021）.With the decrease in the amount of incoming sediment in the river basin, the Yangzhong reach exhibited a continuous state of scouring. The cumulative riverbed scouring volumes of the low-water and flood channels from 1981 to 2021 were 3.97×108 and 4.14×10～8 m3, respectively, with the riverbed scouring volume of the low-water channel accounting for 95.9%of that of the flood channel. Under quasi-natural runoff–sediment conditions, the evolution of the central bars in the Yangzhong reach was highly correlated with the amount of scouring or deposition. In particular, the Luochengzhou reach could be characterized as a meandering river with scouring on concave riverbanks and deposition on convex riverbanks. In the context of reduced incoming sediment, the beach area of the Yangzhong reach decreased by approximately 9.9%（from 2003 to 2021） and the central bars of the straight section areas decreased. Moreover, following operation of the Three Gorges Reservoir, both the Luocheng central bar and Jiangyin beach areas could be characterized as meandering rivers with convex riverbanks and beaches. In the quasi-natural period before the implementation of the waterway improvement project, the trend of high scouring intensity and increased fluid diversion ratio in the right branch of the Luocheng central bar was in accordance with the law that the short branch of the length is in a developing state under the condition of decreasing river sediment volume. With the control of riverbank protection and the construction of waterway improvement projects in the Yangzhong reach, the shapes of the riverban

关键词： riverbed scouring or deposition beach morphology linkage relationship causal analysis tidal reach Yangtze River

Laser-induced inverted patterning of nanocrystals embedded glass for micro-light-emitting diodes

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Journal of Materials Science & Technology 2023年第19期150卷 138-144页

作者： Yuzhou Hu Ying Ye Wenchao Zhang Kai Li Yao Zhou Yudong Zhang Zhao Deng jianjun han Xiujian Zhao Chao Liu State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan University of TechnologyWuhan 430070China

High resolution and full-color light-emitting diodes require precise and efficient patterning of light-emitting structures containing quantum dots or nanocrystals.We report light-induced inverted patterning of nanocrystals in glasses for micro-light-emitting diodes.Ultrafast laser pulse induces structural destruction and amorphization of nanocrystals in glasses,forming inverted luminescent patterns.High-throughput patterning of micrometer-scale,thermally stable,and highly photoluminescent structures in nanocrystals embedded glass is realized.This patterning method provides a novel way to fabricate high-performance and ultrahigh-resolution color conversion layers for micrometer-scale light-emitting diodes.

关键词： Nanocrystals Ultrafast laser Sub-micro patterning Micro-light-emitting-diodes

The high-quality sequencing of the Brassica rapa‘XiangQingCai’genome and exploration of genome evolution and genes related to volatile aroma

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Horticulture Research 2023年第10期10卷 174-184页

作者： Zhaokun Liu Yanhong Fu Huan Wang Yanping Zhang jianjun han Yingying Wang Shaoqin Shen Chunjin Li Mingmin Jiang Xuemei Yang Xiaoming Song Suzhou Academy of Agricultural Sciences SuzhouJiangsu 215155China College of Life Sciences North China University of Science and TechnologyTangshanHebei 063210China Suzhou Polytechnic Institute of Agriculture SuzhouJiangsu 215008China

‘Vanilla’(XQC,brassica variety chinensis)is an important vegetable crop in the Brassica family,named for its strong volatile fragrance.In this study,we report the high-quality chromosome-level genome sequence of XQC.The assembled genome length was determined as 466.11 Mb,with an N50 scaffold of 46.20 Mb.A total of 59.50%repetitive sequences were detected in the XQC genome,including 47570 genes.Among all examined Brassicaceae species,XQC had the closest relationship with B.rapa QGC(‘QingGengCai’)and B.rapa Pakchoi.Two whole-genome duplication(WGD)events and one recent whole-genome triplication(WGT)event occurred in the XQC genome in addition to an ancient WGT event.The recent WGT was observed to occur during 21.59-24.40 Mya(after evolution rate corrections).Our findings indicate that XQC experienced gene losses and chromosome rearrangements during the genome evolution of XQC.The results of the integrated genomic and transcriptomic analyses revealed critical genes involved in the terpenoid biosynthesis pathway and terpene synthase(TPS)family genes.In summary,we determined a chromosome-level genome of B.rapa XQC and identified the key candidate genes involved in volatile fragrance synthesis.This work can act as a basis for the comparative and functional genomic analysis and molecular breeding of B.rapa in the future.

关键词： evolution breeding correction

RNA m^(6)A reader YTHDF2 facilitates precursor miR-126 maturation to promote acute myeloid leukemia progression

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Genes & Diseases 2024年第1期11卷 382-396页

作者： Zheng Zhang Keren Zhou Li han Andrew Small Jianhuang Xue Huilin Huang Hengyou Weng Rui Su Brandon Tan Chao Shen Wei Li Zhicong Zhao Ying Qing Xi Qin Kitty Wang Keith Leung Mark Boldin Chun-Wei Chen David Ann Zhijian Qian Xiaolan Deng jianjun Chen Zhenhua Chen Department of Systems Biology Beckman Research Institute of City of HopeMonroviaCA 91016USA Irell and Manella Graduate School of Biological Sciences Beckman Research Institute of City of HopeDuarteCA 91010USA Gehr Family Center for Leukemia Research City of HopeDuarteCA 91010USA Sun Yat-sen University Cancer Center State Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer MedicineGuangzhouGuangdong 510060China Guangzhou Laboratory GuangzhouGuangdong 510005China Bioland Laboratory GuangzhouGuangdong 51005China Department of Liver Surgery Renji HospitalShanghai Jiao Tong University School of MedicineShanghai 200127China Department of Diabetes Complications and Metabolism Beckman Research Institute of City of HopeDuarteCA 91010USA Department of Biochemistry and Molecular Biology University of FloridaGainesvilleFL 32603USA Tongji Hospital Affiliated to Tongji University Frontier Science Center for Stem Cell ResearchSchool of Life Sciences and TechnologyTongji UniversityShanghai 200092China School of Pharmacy China Medical UniversityShenyangLiaoning 110001China

As the most common internal modification of mRNA,Ne-methyladenosine(m^(6)A)and its regulators modulate gene expression and play critical roles in various biological and patholog-ical processes including tumorigenesis.It was reported previously that m^(6)A methyltransferase(writer),methyltransferase-like 3(METTL3)adds m^(6)A in primary microRNAs(pri-miRNAs)and fa-cilitates its processing into precursor miRNAs(pre-miRNAs).However,it is unknown whether m^(6)A modification also plays a role in the maturation process of pre-miRNAs and(if so)whether such a function contributes to tumorigenesis.Here,we found that YTHDF2 is aberrantly overexpressed in acute myeloid leukemia(AML)patients,especially in relapsed patients,and plays an onco-genic role in AML.Moreover,YTHDF2 promotes expression of miR-126-3p(also known as miR-126,as it is the main product of precursor miR-126(pre-miR-126)),a miRNA that was reported as an oncomiRNA in AML,through facilitating the processing of pre-miR-126 into mature miR-126.Mechanistically,YTHDF2 recognizes m^(6)A modification in pre-miR-126 and recruits AGO2,a regulator of pre-miRNA processing,to promote the maturation of pre-miR-126.YTHDF2 posi-tively and negatively correlates with miR-126 and miR-126's downstream target genes,respec-tively,in AML patients,and forced expression of miR-126 could largely rescue YTHDF2/Ythdf2 depletion-mediated suppression on AML cell growth/proliferation and leukemogenesis,indi-cating that miR-126 is a functionally important target of YTHDF2 in AML.Overall,our studies not only reveal a previously unappreciated YTHDF2/miR-126 axis in AML and highlight the ther-apeutic potential of targeting this axis for AML treatment,but also suggest that m^(6)A plays a role in pre-miRNA processing that contributes to tumorigenesis.

关键词： AML miR-126 N^(6)-methyladenosine Pre-miRNA maturation YTHDF2

粮食安全与生态可持续耦合协调研究——以长江经济带为例

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生态经济 2024年第7期40卷 196-202页

作者：韩建军杨雅冰河南工业大学土木工程学院河南郑州450001

基于2006—2020年长江经济带省际面板数据,构建粮食安全与生态可持续评价指标体系,利用熵值法测算长江经济带两系统的综合发展水平,运用耦合协调度与障碍度模型分析粮食与生态的耦合协调特征及其障碍因子。结果表明:(1)2006—2020年长... 详细信息

基于2006—2020年长江经济带省际面板数据,构建粮食安全与生态可持续评价指标体系,利用熵值法测算长江经济带两系统的综合发展水平,运用耦合协调度与障碍度模型分析粮食与生态的耦合协调特征及其障碍因子。结果表明:(1)2006—2020年长江经济带粮食安全综合指数持续上升,生态可持续综合指数波动上升。(2)两系统耦合协调度呈良性增长趋势,表现为“西高东低”的空间分布特征且空间聚集性不断增强。(3)当年造林面积、城市污水日处理能力、居民人均可支配收入、地方财政环境保护支出和财政支农等是制约长江经济带粮食生态协调发展的主要障碍因子。

关键词：长江经济带粮食安全生态可持续耦合协调障碍度

南海北部扩张的地表过程响应:来自海南岛五指山的磷灰石裂变径迹年龄证据

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地质学报 2024年第2期98卷 421-432页

作者：史军华韩帅杜建军韩建恩孙东霞胡道功中国地质科学院地质力学研究所北京100081 中国地质大学北京100083

海南岛是南海地块的重要组成部分,其构造演化很大程度上能够反映整个南海的构造活动特征。新生代,海南岛在新构造运动作用下,断块差异升降比较明显,形成了大致以王五-文教断裂为界,北为沉降区,南为断隆区的构造格局。对断隆区隆升过程... 详细信息

海南岛是南海地块的重要组成部分,其构造演化很大程度上能够反映整个南海的构造活动特征。新生代,海南岛在新构造运动作用下,断块差异升降比较明显,形成了大致以王五-文教断裂为界,北为沉降区,南为断隆区的构造格局。对断隆区隆升过程的研究能够帮助揭示海南岛新构造活动历史,但至今为止,琼中南山地隆升的原因和时限仍存在争议。为了厘清海南岛中部的剥露隆升事件,本文选择琼中南地区海拔最高、高差最大的五指山为研究区,采集8组高程岩石样品,高程范围为203.55~1153.52 m。对采集的样品进行了磷灰石裂变径迹测试和热历史模拟分析,结果表明海南岛五指山地区新生代主要经历了两期快速隆升剥露。第一期为渐新世—中新世(32~17 Ma):隆升速率较快,此时期太平洋板块向欧亚板块俯冲后撤,南海正经历第二次扩张,使得海南岛拉张,活动强烈,造成琼中山地区快速隆升,直到中中新世转为缓慢隆升。第二期为中新世末期(5 Ma)的快速剥蚀隆升阶段:南海扩张已经结束,随着菲律宾板块俯冲亚洲板块,南海北部陆缘整体处于加速热沉降阶段,且全球气候变化加快,造成了海南岛广泛的隆起和加速剥蚀。

关键词：裂变径迹新生代构造运动隆升与剥露历史海南岛五指山

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纯钛TIG焊接接头的高温氧化行为

稀有金属材料与工程 2024年第2期53卷 350-356页

作者：韩礼红杨尚谕王建军雒设计李丹刘明中国石油集团工程材料研究院有限公司油气钻采输送装备全国重点实验室陕西西安710077 西安石油大学材料科学与工程学院陕西西安710065 西安交通大学材料科学与工程学院金属材料强度国家重点实验室陕西西安710049

对纯钛氩弧焊焊接接头在550℃下氧化不同时间(2,4,6,8h)以及在不同温度(650,750,850,950℃)下氧化4h的氧化动力学、氧化形态和氧化产物进行了研究。结果表明,在550℃下,氧化时间对焊接接头氧化行为的影响有限,而氧化温度对纯钛焊接接头... 详细信息

对纯钛氩弧焊焊接接头在550℃下氧化不同时间(2,4,6,8h)以及在不同温度(650,750,850,950℃)下氧化4h的氧化动力学、氧化形态和氧化产物进行了研究。结果表明,在550℃下,氧化时间对焊接接头氧化行为的影响有限,而氧化温度对纯钛焊接接头的氧化行为有显著影响,且温度越高,氧化越严重。在低温下,纯钛焊接接头的氧化动力学接近准线性定律,随着温度升高,氧化速率呈指数增长。此外,焊接接头表面产生的氧化产物是具有锐钛矿和金红石结构的TiO_(2),温度对TiO_(2)的类型没有明显影响。纯钛焊接接头的氧化过程可描述为:氧气在表面被吸收;氧化物优先在缺陷区形核;氧化物横向生长、增厚。在较高温度下,氧化膜中出现裂纹或空隙,成为O原子传输通道,导致O和Ti原子的高扩散速率和氧化速率。

关键词：焊接接头氧化处理氧化动力学氧化膜