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Miocene Bahean stratigraphy in the Longzhong Basin, northern central china and its imp{1.cations in environmental change

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Science china Earth Sciences 2006年第12期49卷 1270-1279页

作者： li Jijun1,2, ZHANG jun1, SONG Chunhui1, ZHAO Zhijun2, ZHANG Yong1, WANG Xiuxi 1, ZHANG Jianming1.& CUI Qiaoyu1 1. Key Laboratory of western china’s Environmental Systems (Ministry of Education) & college of Earth and Environment Sciences, Lanzhou university, Lanzhou 730000, china 2. Jiangsu Key Laboratory of Environmental Change and Ecological Construction & college of Geography, nanjing normal university, nanjing 210097, china 1. Key Laboratory of western {1.’s Environmental Systems (Ministry of Education) & college of Earth and Environment Sciences Lanzhou University Lanzhou 730000 China 2. Jiangsu Key Laboratory of Environmental Change and Ecological Construction & college of Geography Nanjing Normal University Nanjing 210097 China

Fossil mammal-riched Neogene strata are widely distributed in the southeast corner of the huge Longzhong Basin at Tianshui, Gansu Province, northern central china. Hipparion weihoense, a typical member of late Middle Miocene Bahean stage, was recently excavated at Yaodian along a well-exposed outcrop. Owing to the importance of the Bahean stage in the mamma{1.an evolution and its potential for environmental change, we suggested a name of Yaodian Formation for the stratigra- phy, which is correlated to the Bahe Formation at Lantian, Shaanxi. High resolution paleomagnetic dating of the section shows that the Yaodian Formation covers the period between 1..67 Ma and 7.43 Ma, with the site bearing Hipparion weihoense being estimated at about 1..54―1..30 Ma, providing first magnetostratigraphic chronology for the Bahean Stage. The Yaodian Formation consists of fluvial channel deposits (1..67―1..40 Ma) at the bottom, floodplain deposits in the middle (1..40―9.23 Ma) and shallow lake sediments at the top (9.23―7.43 Ma). This upward fining sequence suggests that the re{1.ef in nearby mountain ranges such as west Qin{1.ng to the south and Huajia {1.ng to the north was greatly reduced after long-term denudation, fluvial transport capacity was low, and finally the drainage system was disintegrated, replaced with broad-shallow lakes in which only fine sediments {1.ke mud and mar{1.te were deposited, indicating an old stage of development of a planation surface. A remarkable shift in ecology and c{1.matic environment was found at 7.4―7.7 Ma when paleoc{1.mate changed from early warm humid to late dry as indicated by sedimentary facies changed from early shallow lake sequence to late eo{1.an red clays and a former coniferous-deciduous mixed forest was replaced by grassland, leading to great growth of Hipparion Fauna of Baodean stage in the region. Therefore, it is estimated that the present high re{1.ef of Qin{1.ng and drainage pattern did not come into being until Late P{1.ocene in response

关键词： Bahean stage,magnetostratigraphy,Yaodian Formation,Neogene,Longzhong Basin.

Adsorption and adhesion of blood proteins and fibroblasts on multi-wall carbon nanotubes

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Science china({1.fe Sciences) 2009年第5期52卷 479-482页

作者： li Dejun1, YUAN li1, YANG Ying1, DENG XiangYun1, Lü XiaoYing2, huang Yan2, CAO Zheng2, liU Hao3 & SUN Xueliang3 1.college of Physics and Electronic information Science, Tianjin normal university, Tianjin 300074, china 2 State Key Laboratory of Bioelectronics, Southeast university, nanjing 210096, china 3 Department of Mechanical & Materials Engineering, university of western Ontario, London, ON, Canada college of Physics and Electronic {1. Science Tianjin Normal University Tianjin 300074 China State Key Laboratory of Bioelectronics Southeast University Nanjing 210096 China Department of Mechanical & Materials Engineering University of Western Ontario London ON Canada

This article concerns the investigation of blood protein adsorption on carbon paper and multi-wall carbon nanotubes (MWCNTs). Mouse fibroblast cell adhesion and growth on MWCNTs was also studied. The results showed that fibrinogen adsorption on carbon paper was much lower than that on MWCNTs, which means that platelets readily aggregate on the surface of MWCNTs. Mouse fibroblast cells implanted on MWCNTs tended to grow more prolifically than those implanted on carbon paper. The cell concentration observed on MWCNTs increased from 1.2×1.5/mL for a single day culture to 2×1.5/mL for a 7-day culture. No toxicity reaction was observed during the culturing period. These results indicated that MWCNTs possessed excellent tissue compatibility.

关键词： multi-wall carbon nanotubes cell adhesion protein adsorption toxicity tissue compatibility

Manipulating d-d orbital hybridization induced by Mo-doped Co_(9)S_(8) nanorod arrays for high-efficiency water electrolysis

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Journal of Energy Chemistry 2024年第6期93卷 592-600,I0015页

作者： Xue Zhou Jing li Guangyao Zhou Weiran {1. Yucan Zhang jun Yang Huan Pang Mingyi Zhang Dongmei Sun Yawen Tang lin Xu Jiangsu Key Laboratory of New Power Batteries Jiangsu Collaborative Innovation Centre of Biomedical Functional MaterialsSchool of Chemistry and Materials ScienceNanjing Normal UniversityNanjing 210023JiangsuChina 'college of Science Jinling Institute of TechnologyNanjing 211169JiangsuChina State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China nanjing IPE Institute of Green Manufacturing Industry Nanjing 211100JiangsuChina School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 225009JiangsuChina Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Physics and Electronic EngineeringHarbin Normal UniversityHarbin 150025HeilongjiangChina

Precisely refining the electronic structure of electrocatalysts represents a powerful approach to further optimize the electrocatalytic ***,we demonstrate an ingenious d-d orbital hybridization concept to construct Mo-doped Co_(9)S_(8) nanorod arrays aligned on carbon cloth(CC)substrate(abbreviated as Mo-Co_(9)S_(8)@CC hereafter)as a high-efficiency bifunctional electrocatalyst toward water *** has experimentally and theoretically validated that the 4d-3d orbital coupling between Mo dopant and Co site can effectively optimize the H_(2)O activation energy and lower H^(*)adsorption energy barrier,thereby leading to enhanced hydrogen evolution reaction(HER)and oxygen evolution reaction(OER)*** to the unique electronic and geometrical advantages,the optimized Mo-Co_(9)S_(8)@CC with appropriate Mo content exhibits outstanding bifunctional performance in alkaline solution,with the overpotentials of 75 and 234 mV for the delivery of a current density of 1. mA cm^(-2),small Tafel slopes of 53.8 and 39.9 mV dec~(-1.and long-term stabilities for at least 32 and 30 h for HER and OER,*** impressively,a water splitting electrolylzer assembled by the self-supported Mo-Co_(9)S_(8)@CC electrode requires a low cell voltage of 1.53 V at 1. mA cm^(-2)and shows excellent stability and splendid reversibility,demonstrating a huge potential for affordable and scalable electrochemical H_(2) *** innovational orbital hybridization strategy for electronic regulation herein provides an inspirable avenue for developing progressive electrocatalysts toward new energy systems.

关键词： d-d orbital hybridization Transition metal sulfides Nanorods arrays Water electrolysis

The Impact of Homework Time on Academic Performance and Its Mechanism:Optimal Homework Time under the"Double Reduction"Policy

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Frontiers of Education in china 2024年第3期19卷 251-270页

作者： li Bo WANG {1. huang Bin School of Public Administration Nanjing University of Finance and EconomicsNanjing 210023China Business School Beijing Normal UniversityBeijing 100875China School of Education NanjingUniversityNanjing 210023China

Using data from the china Education Panel Survey,this study examines the impact of homework time on academic performance among Chinese {1.ior high school *** findings show that seventh and ninth graders spend 2.28 and 2.67 hours daily on homework,respectively,exceeding the 90-minute limit stipulated by the"double reduction"*** time significantly varies by gender,grade,and *** relationship between homework time and the academic performance of {1.ior high school students follows an inverted U-shaped *** Least Squares analysis indicates that the optimal homework time for maximizing academic performance is less than 0.96 hours per *** the threshold,the positive effect diminishes,and when homework time exceeds 4.07 hours,it negatively impacts academic *** effect analysis shows that excessive homework time leads to negative emotions,such as boredom,unhappiness,frustration,and sadness while depriving students of necessary sleep for healthy *** is concluded that optimal daily homework time is about 1.hour,aligning with the"double reduction"policy guidelines.

关键词： homework time academic performance threshold model mediating effect

Strain‑Induced Surface Interface Dual Polarization Constructs PML‑Cu/Bi_(1.)O_(1.)Br_(2) High‑Density Active Sites for CO_(2) Photoreduction

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Nano-Micro Letters 2024年第5期16卷 169-183页

作者： Yi Zhang Fangyu Guo jun Di Keke Wang Molly Meng‑jung li Jiayu Dai Yuanbin She Jiexiang Xia Huaming li School of Chemistry and Chemical Engineering Institute for Energy ResearchSchool of the Environment and Safety EngineeringJiangsu UniversityZhenjiang 212013People’s Republic of China State Key Laboratory Breeding Base of Green Chemistry‑Synthesis Technology College of Chemical EngineeringZhejiang University of TechnologyHangzhou 310014People’s Republic of China college of Science and Hunan Key Laboratory of Extreme Matter and ApplicationsNational University of Defense TechnologyChangsha 410073People’s Republic of China Department of Applied Physics The Hong Kong Polytechnic UniversityHung HomHong KongPeople’s Republic of China School of Chemistry and Chemical Engineering National Special Superfine Powder Engineering Research CenterNanjing University of Science and TechnologyNanjing 210094People’s Republic of China Key Laboratory of the Ministry of Education for Advanced Catalysis Materials Zhejiang Normal UniversityJinhua 321004People’s Republic of China

The insufficient active sites and slow interfacial charge trans-fer of photocatalysts restrict the efficiency of CO_(2) *** synchronized modulation of the above key issues is demanding and ***,strain-induced strategy is developed to construct the Bi–O-bonded interface in Cu porphyrin-based monoatomic layer(PML-Cu)and Bi_(1.)O_(1.)Br_(2)(BOB),which triggers the surface interface dual polarization of PML-Cu/BOB(PBOB).In this multi-step polarization,the built-in electric field formed between the interfaces induces the electron transfer from con-duction band(CB)of BOB to CB of PML-Cu and suppresses its reverse ***,the surface polarization of PML-Cu further promotes the electron converge in Cu *** introduction of PML-Cu endows a high density of dispersed Cu active sites on the surface of PBOB,significantly promoting the adsorption and activation of CO_(2) and CO *** conversion rate of CO_(2) photoreduction to CO for PBOB can reach 584.3μmol g-1.which is 7.83 times higher than BOB and 20.01.times than *** work offers valuable insights into multi-step polarization regulation and active site design for catalysts.

关键词： Bi_(1.)O_(1.)Br_(2) Porphyrin CO_(2)photoreduction Polarization Active sites

Fractionation of Heavy Metals in Sediments from Dianchi Lake,china

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Pedosphere 2007年第2期17卷 265-272页

作者： li Ren-Ying YANG Hao ZHOU Zhi-Gao Lü {1.-Jie SHAO Xiao-Hua JIN Feng State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences Nanjing 210008 （China）. college of Geography Science Nanjing Normal University Nanjing 210097 （China） Department of Applied Meteorology Nanjing University of Information Science ＆ Technology Nanjing 210044 （China）

Fractionation of heavy metals in sediments can help in understanding potential hazards of heavy metals. The present study analyzed total concentrations and fractions of selected heavy metals （Cd, Cr, Cu, Pb, and Zn） in surface sediments from Dianchi Lake, Yunnan Province, china, as well as factors that may affect distributions of the various heavy metal fractions. Total concentrations of the heavy metals decreased in the order Zn 〉 Cu 〉 Pb 〉 Cr 〉 Cd. These heavy metals, except Cr, were much higher than their background levels, indicating that Dianchi Lake was polluted by Cd, Zn, Pb, and Cu. Cadmium occurred mainly as the non-residual fraction （sum of the HOAc-soluble, reducible, and oxidizable fractions）（97.6%）, and Zn （55.7%） was also predominantly found in the non-residual fraction. In contrast, most of the Cr （88.5%）, Pb （81.8%）, and Cu （59.2%） occurred in the residual fraction. Correlation analysis showed that total heavy metal concentrations, organic matter and reducible Fe were the main factors affecting the distributions of the various heavy metal fractions. In the Walhai section of Dianchi Lake （comprising 97% of the lake area）, the concentrations of Cd, Zn, Pb, and Cu in the non-residual fraction were significantly lower （P ≤ 0.01.or 0.05） than those of the Caohal section （3% of the lake area）. This indicated that potential heavy metal hazards in the Caohai section were greater than the Waihai section.

关键词： Dianchi Lake heavy metal fractions lake sediment organic matter reducible Fe

Does china's digital economy contribute to low-carbon transition?

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Ecological Economy 2024年第2期20卷 102-122页

作者： li {1.-{1. huang Xin-yu CHEN Mu ZHANG Meng-jiang ZHANG Zhen School of Economics Fujian Normal UniversityFuzhou 350007CHINA college of Mechanical and Electrical Engineering Wuyi UniversityNanping 354300CHINA

The digital economy,as a new emerging economic form,has become an important power for realizing Chinese-style modernization and promoting green development in *** paper measures the digital economy and low-carbon transition index based on the data of 30 provinces in {1. from 201. to 2020 and analyzes the mechanism and path of the digital economy affecting low-carbon transition using the fixed effect panel data model and the threshold effect *** is found that,(1.The digital economy and low-carbon transition in {1. are various in different regions,with characteristics of being unbalanced and insufficient.(2)The digital economy significantly promotes low-carbon transition,with the greatest influence in the Central region,followed by the Eastern region and the western *** different dimensions,the development of informatization and digital transactions promote low-carbon transition,but the development of the internet plays an inhibiting role.(3)The higher the degree of urbanization and environmental regulation,the greater the influence of the digital economy on low-carbon transition.

关键词： digital economy low-carbon transition threshold effect model instrumental variables quantile regression

Advancements of Macrophages Involvement in Pathological Progression of Colitis-Associated Colorectal Cancer and Associated Pharmacological Interventions

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Chinese Journal of Integrative Medicine 2024年第6期30卷 565-576页

作者： KE jun-yu SONG Jin-bin {1. Long HE Zhen-fan huang Zhuo-jian {1.U Zheng-{1.n CHEN Gui-rong WANG Hai-yan WEN Su-ru ZHOU Heng-{1. MA Hui-{1.n DU Qun WU Yong-qiang {1. Yan-wu CHEN Xin-{1.n School of Basic Medical Sciences Guangzhou University of Chinese MedicineGuangzhou510006China Department of Surgery II Gaozhou Hospital of Traditional Chinese Medicine Affiliated to Guangzhou University of Chinese MedicineGaozhou525200China Science and Technology Innovation Center Guangzhou University of Chinese MedicineGuangzhou510405China The First Clinical Medical {1. of Guangzhou university of Traditional Chinese Medicine Guangzhou510405China

Intestinal macrophages play crucial roles in both intestinal inflammation and immune homeostasis. They can adopt two distinct phenotypes, primarily determined by environmental cues. These phenotypes encompass the classically activated pro-inflammatory M1.phenotype, as well as the alternatively activated anti-inflammatory M2 phenotype. In regular conditions, intestinal macrophages serve to shield the gut from inflammatory harm. However, when a combination of genetic and environmental elements influences the polarization of these macrophages, it can result in an M1.M2 macrophage activation imbalance, subsequently leading to a loss of control over intestinal inflammation. This shift transforms normal inflammatory responses into pathological damage within the intestines. In patients with ulcerative co{1.tis-associated colorectal cancer (UC-CRC), disorders related to intestinal inflammation are closely correlated with an imbalance in the polarization of intestinal M1.M2 macrophages. Therefore, reinstating the equi{1.brium in M1.M2 macrophage polarization could potentially serve as an effective approach to the prevention and treatment of UC-CRC. This paper aims to scrutinize the c{1.nical evidence regarding Chinese medicine (CM) in the treatment of UC-CRC, the pivotal role of macrophage polarization in UC-CRC pathogenesis, and the potential mechanisms through which CM regulates macrophage polarization to address UC-CRC. Our objective is to offer fresh perspectives for c{1.nical app{1.cation, fundamental research, and pharmaceutical advancement in UC-CRC.

关键词： macrophage ulcerative colitis colon cancer Chinese medicine

分子串模型中空间弛豫模式的弛豫动力学的蒙特卡罗模拟

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物理学报 2011年第12期60卷 400-405页

作者：樊小辉赵兴宇王丽娜张丽丽周恒为张晋鲁黄以能伊犁师范学院物理科学与技术学院新疆凝聚态相变与微结构实验室伊宁835000 南京大学物理学院固体微结构物理国家重点实验室南京210093 新疆教育学院科研处乌鲁木齐830043

基于玻璃化转变的分子串模型的分子串弛豫方程,提出了更为精确的模拟分子串中所有空间弛豫模式(SRM)的蒙特卡罗模拟方案.模拟得出各个SRM的弛豫时间随温度和分子串长度的变化结果与分子串模型中分子串弛豫方程的预言完全一致,即理论预... 详细信息

基于玻璃化转变的分子串模型的分子串弛豫方程,提出了更为精确的模拟分子串中所有空间弛豫模式(SRM)的蒙特卡罗模拟方案.模拟得出各个SRM的弛豫时间随温度和分子串长度的变化结果与分子串模型中分子串弛豫方程的预言完全一致,即理论预期和模拟结果相互印证.应当指出,分子串能否作为液态中集体单元的必要条件是在考虑到分子串之间的不均匀随机相互作用后,分子串的所有SRM的定性特征是不能改变的,这就需要对不同分子串的SRM之间的耦合进行研究.但是迄今为止,仍未发现相关的严格解,仅有近似的自洽弛豫平均场方法.由此可知,所提出的模拟方案为研究不同分子串的SRM之间的耦合(包括上述自洽场的可行性)提供了必要的基础.

关键词：玻璃化转变弛豫动力学蒙特卡罗模拟分子串