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Quantification,morphology and source of humic acid,kerogen and black carbon in offshore marine sediments from Xiamen Gulf,China

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Journal of Environmental Sciences 2013年第2期25卷 287-294页

作者： yanting chen Jinping Zhao Liqian Yin Jinsheng chen Dongxing Yuan Key Laboratory of Urban Environment and Health Institute of Urban EnvironmentChinese Academy of Sciences Environmental Science and Engineering Department Huaqiao University Guangdong Environmental Monitoring Center State Key Laboratory of Marine Environmental Science Xiamen University

Three types of macromolecular organic matters （MOMs）, i.e. humic acid （HA）, kerogen＋black carbon （KB）, and black carbon （BC） were extracted from marine sediments of Xiamen Gulf, southeast of China. The chemical composition, morphological property and source of the three extractions were characterized by elemental analyzer/isotope ratio mass spectrometry （EA/IRMS） and scanning electron microscope （SEM）. The results showed that KB was the predominant fraction in MOMs, which accounted for 61.79%-89.15% of the total organic content （TOC）, while HA consisted less than 5%. The relative high contents of kerogen and BC, and low contents of HA in the samples indicated that anthropogenic input might be the major source of organic matter in marine sediments near the industrial regions. The characterization of SEM, not only revealed morphological properties of the three fractions, but also allowed a better understanding of the source of MOMs. The δ 13 C values of the three fractions suggested that materials from terrestrial C 3 plants were predominant. Furthermore, the anthropogenic activities, such as the discharge of sewage, coal and biomass combustion from industry nearby and agricultural practices within drainage basin of the Jiulong River, were remarkably contributed to the variations in δ 13 C values of MOMs in the offshore marine sediments.

关键词： macromolecular organic matters elemental analyzer/isotope ratio mass spectrometry scanning electron microscope offshore marine sediment Xiamen

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Excellent alkali resistance of Fe,Ce and sulfates co-modified V_(2)O_(5)-WO_(3)/TiO_(2) catalyst for selective catalytic reduction of NO_(x) with NH_(3)

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Journal of Rare Earths 2024年第9期42卷 1682-1692,I0002页

作者： Biyi Huang Xianfang Yi Jianyi Zhang Yuqiu Liu yanting chen Jinsheng chen Jinxiu Wang Center for Excellence in Regional Atmospheric Environment and Key Lab of Urban Environment and HealthInstitute of Urban EnvironmentChinese Academy of SciencesXiamen361021China College of Resources and Environment Fujian Agriculture and Forestry UniversityFuzhou350002China Fujian Key Laboratory of Atmospheric Ozone Pollution Prevention Institute of Urban EnvironmentChinese Academy of SciencesXiamen361021China University of Chinese Academy of Sciences Beijing100049China

Improving the alkali resistance of catalysts for selective catalytic reduction of NO_(x) with NH_(3) is still a *** this work,the co-modification with Fe,Ce and sulfates on V_(2)O_(5)-WO_(3)/TiO_(2) catalysts(denoted as xSFeCeVWTi) significantly enhances its alkali resistance with K element as a representative.A series of xSFeCeVWTi catalysts was synthesized by wet impregnation with designed 0.05Fe/V, 1.5Ce/V and different S/V molar ratios *** NO_(x) conversion and K resistance of xSFeCeVWTi catalysts increase with the increase of loading amounts of sulfates but no longer further increase as the sulfates load is excessive to block the pores of catalysts and hinder the adsorption of *** optimal modified catalyst in about 2.2S/V actual loading ratio,corresponding to 10.5SFeCeVWTi sample,shows over 99.0%NO_(x) conversion and N_(2) selectivity at 300-400℃ after *** interaction between Fe,Ce and V improves its redox ability but slightly weakens surface acidity,while the proper amount of sulfate species enriches surface Br?nsted acid sites but attenuates its redox ***,a balance of redox capacity and surface acidity,caused by Fe,Ce and sulfate co-modification,contributes to the excellent K resistance of 10.5SFeCeVWTi ***,the change of physicochemical properties influences the reaction mechanism which follows the Eley-Rideal mechanism on *** *** results show that the co-modification with Fe,Ce and sulfates is a good way to improve the alkali tolerance of V_(2)O_(5)-WO_(3)/TiO_(2) catalyst in industrial applications.

关键词： SCR CeO_(2) Fe_(2)O_(3) SO_(4)^(2-) K resistance K poisoning

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The COVID-19 pandemic and Alzheimer’s disease: mutual risks and mechanisms

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Translational Neurodegeneration 2022年第1期11卷 343-360页

作者： Feng chen yanting chen Yongxiang Wang Qiongwei Ke Lili Cui Guangdong Key Laboratory of Age-Related Cardiac and Cerebral Diseases Department of NeurologyAffiliated Hospital of Guangdong Medical Univer-sityZhanjiangChina Key Laboratory of Animal Models and Human Disease Mechanisms of the Chinese Academy of Sciences&Yunnan Province Kunming Institute of Zoology Chinese Academy of Sciences KunmingYunnanChina.

Coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS- CoV-2), is a life-threatening disease, especially in elderly individuals and those with comorbidities. The predominant clinical manifestation of COVID-19 is respiratory dysfunction, while neurological presentations are increasingly being recognized. SARS-CoV-2 invades host cells primarily via attachment of the spike protein to the angiotensin-converting enzyme 2 (ACE2) receptor expressed on cell membranes. Patients with Alzheimer’s disease (AD) are more susceptible to SARS-CoV-2 infection and prone to severe clinical outcomes. Recent studies have revealed some common risk fac-tors for AD and COVID-19. An understanding of the association between COVID-19 and AD and the potential related mechanisms may lead to the development of novel approaches to treating both diseases. In the present review, we first summarize the mechanisms by which SARS-CoV-2 invades the central nervous system (CNS) and then discuss the associations and potential shared key factors between COVID-19 and AD, with a focus on the ACE2 receptor, apolipo-protein E (APOE) genotype, age, and neuroinflammation.

关键词： SARS-CoV-2 COVID-19 Alzheimer’s disease ACE2 APOE Age Neuroinflammation

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Sources appointment and health risks of PM_(2.5)-bound trace elements in a coastal city of southeastern China

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Journal of Environmental Sciences 2024年第4期138卷 561-571页

作者： Ziyi Lin Xiaolong Fan Gaojie chen Youwei Hong Mengren Li Lingling Xu Baoye Hu chen Yang yanting chen Zhiqian Shao Jinsheng chen Center for Excellence in Regional Atmospheric Environment Institute of Urban EnvironmentChinese Academy of SciencesXiamen 361021China Key Lab of Urban Environment and Health Institute of Urban EnvironmentChinese Academy ofSciencesXiamen 361021China University of Chinese Academy of Sciences Beijing 100049China Minnan Normal University Zhangzhou 363000China

To gain a comprehensive understanding of sources and health risks of trace elements in an area of China with high population densities and low PM_(2.5)concentrations,15 trace elements(Al,K,Ca,Ti,V,Cr,Mn,Fe,Ni,Cu,Zn,As,Sn,Ba,Pb)in PM_(2.5)were monitored from December 2020 to November 2021 in a representative city,*** concentrations of trace elements in Xiamen displayed an obvious seasonal variation and were dominated by K,Fe,Al,Ca and *** on Positive Matrix Factorization analysis,source appointment revealed that the major sources of trace elements in Xiamen were traffic,dust,biomass and firework combustion,industrial manufacture and shipping *** to health risk assessment combined with the source appointment results,it indicated that the average noncarcinogenic risk was below the threshold and cancer risk of four hazardous metals(Cr,Ni,As,Pb)exceeded the threshold(10^(-6)).Traffic-related source had almost half amount of contribution to the health risk induced by PM_(2.5)-bound trace *** the dust transport period or Spring Festival period,the health risks exceeded an acceptable threshold even an order of magnitude higher,suggesting that the serious health risks still existed in low PM_(2.5)environment at certain *** risk assessment reminded that the health risk reduction in PM_(2.5)at southeastern China should prioritize traffic-related hazardous trace elements and highlighted the importance of controlling vehicles emissions in the future.

关键词： PM_(2.5)-bound trace elements Seasonal variations Source appointment Health risks Traffic-related source

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Sustainable curcumin-based smart tough fluorescent hydrogels for anti-counterfeiting applications

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Green Chemical Engineering 2023年第4期4卷 379-386页

作者： Xiubin Xu Chuanghong Xiao yanting chen Danfeng Yu Yu Lu Ian Wyman Xu Wu School of Chemistry and Chemical Engineering Guangzhou UniversityGuangzhou510006China Department of Chemistry Queen's UniversityKingstonOntarioK7L 3N6Canada

There is currently great interest in developing an environment-friendly,low-cost,and scalable approach for producing stimuli-responsive fluorescent hydrogels(FHs)with excellent mechanical property,rewritable fluorescence,and dual anti-counterfeiting ***,by applying natural,environment-friendly,and sustainable curcumin as a responsive agent,tough pH-responsive FHs(pH-FHs)are fabricated via a facile preparation *** materials have outstanding mechanical performances:ultimate stress of 180 kPa,an ultimate strain of~2500%,and good anti-fatigue performances against *** pH-FHs are able to sense ammonia and formaldehyde gas,resulting in both a color change and fluorescence for dual anti-counterfeiting *** sensing information is stored individually by the pH-FHs and could be externally removed using formaldehyde gas to achieve a rewritable *** study provides valuable insights that are expected to facilitate the development of smart FHs for information encryption and anti-counterfeiting applications.

关键词： Curcumin Fluorescence hydrogels Anti-counterfeiting Information storage Rewritable fluorescence

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Band alignment and polarization engineering inκ-Ga_(2)O_(3)/GaN ferroelectric heterojunction

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Science China(Physics,Mechanics & Astronomy) 2022年第7期65卷 147-152页

作者： yanting chen Hongkai Ning Yue Kuang Xing-Xing Yu He-He Gong Xuanhu chen Fang-Fang Ren Shulin Gu Rong Zhang Youdou Zheng Xinran Wang Jiandong Ye School of Electronic Science and Engineering Nanjing UniversityNanjing 210023China

Ferroelectric-semiconductor heterostructures offer an alternative strategy to manipulate polarization towards advanced devices with engineered functionality and improved *** this work,we report on the heteroepitaxial construction,band structure alignment and polarization engineering of the single-phasedκ-Ga_(2)O_(3)/GaN ferroelectric/polar heterojunction.A type-II band alignment is determined at theκ-Ga_(2)O_(3)/GaN polar hetero-interface,with a valence band offset of(1.74±0.1)eV and a conduction band offset of(0.29■0.1)*** the band edge discontinuity,charge dipoles induced by spontaneous polarization lead to the observed band bending with built-in potentials of 0.9 and 0.33 eV,respectively,at theκ-Ga_(2)O_(3)surface andκ-Ga_(2)O_(3)/GaN *** polarization switching properties of ferroelectricκ-Ga_(2)O_(3)are identified with a remanent polarization of approximately 2.7μC/cm^(2)via the direct hysteresis remanent polarization/voltage(P-V)loop *** findings allow the rational design ofκ-Ga_(2)O_(3)ferroelectric/polar heterojunction for the application of power electronic devices,advanced memories and even ultra-low loss negative capacitance transistors.

关键词： wide-bandgap semiconductors ferroelectric polarization band alignment

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120 MPa高强混凝土型钢组合构件受力性能试验研究

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建筑结构学报 2019年第S01期40卷 386-394页

作者：陈嫣婷杜咏周汇凯南京工业大学土木工程学院江苏南京211816

进行了120 MPa高强混凝土型钢组合短柱、组合梁的受压及受弯性能试验,考察箍筋间距和钢纤维掺量对高强混凝土型钢组合短柱的破坏形态、承载力和延性的影响,得到荷载-位移曲线及轴力-应变曲线。研究表明:随着双肢箍筋间距加密,组合短柱... 详细信息

进行了120 MPa高强混凝土型钢组合短柱、组合梁的受压及受弯性能试验,考察箍筋间距和钢纤维掺量对高强混凝土型钢组合短柱的破坏形态、承载力和延性的影响,得到荷载-位移曲线及轴力-应变曲线。研究表明:随着双肢箍筋间距加密,组合短柱虽然仍表现为脆性破坏,但箍筋加密增强了混凝土对型钢的约束效应;随着钢纤维掺量从0.3%增加到0.5%,试件表现为延性破坏。组合短柱在小偏压时发生截面承载力破坏,在大偏压时发生弯曲破坏;组合梁由于箍筋加密为50 mm,增强了混凝土对型钢的约束,并且0.5%钢纤维掺入提高了混凝土的抗拉强度,形成塑性铰时,型钢达到全截面屈服,端部未出现型钢推出现象。通过试验值与EC4计算值比较可得,现行EC4规范可准确估算120 MPa混凝土型钢组合短柱及组合梁在大偏心受压和纯弯状态下的承载力,但对轴心受压和小偏心受压短柱的承载力估算偏小,其N-M曲线不能直接扩展用于120 MPa混凝土型钢柱承载力验算。

关键词： 120 MPa高强混凝土型钢组合构件箍筋间距钢纤维掺量静力试验受力性能

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南音的北京传播

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中国音乐学 2021年第4期4卷 74-78页

作者：陈燕婷中国艺术研究院音乐研究所

南音北京传播可分为演出、教学、讲座、会议等多种方式。传播内容方面,考虑到观众接受能力,往往有不同程度的变化与创新。进京团体主要为新型的、现代化的南音组织,多数受高等院校及研究机构等国有单位邀请而来。南音的北京传播具有双... 详细信息

南音北京传播可分为演出、教学、讲座、会议等多种方式。传播内容方面,考虑到观众接受能力,往往有不同程度的变化与创新。进京团体主要为新型的、现代化的南音组织,多数受高等院校及研究机构等国有单位邀请而来。南音的北京传播具有双向影响,既增进人们对南音的了解,又令南音人倍感荣耀。笔者认为,南音的北京传播还应更加多样化,除了方式、曲目多样化外,进京社团组织也应该多样化。

关键词：南音北京传播

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Effect of Iodine Nutrition during Pregnancy on Physical Growth of Infants at 18-24 months

Effect of Iodine Nutrition during Pregnancy on Physical Grow...

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中国营养学会第十五届全国营养科学大会

作者： yanting chen Wanqi Zhang Wen Wu Ziyun Pan Wenxing Guo Department of Nutrition and Food Hygiene School of Public Health Tianjin Medical University Department of Epidemiology and Biostatistics School of Public Health Guangdong Medical University

Severe iodine deficiency during pregnancy can cause series of adverse effects, including irreversible harm on infants brain and physical growth. While the effect of mild iodine deficiency during pregnancy on their infants physical growth is still uncertain and further studies are needed to conform it. This study aimed to evaluate the effects of iodine nutrition during pregnancy on their infants physical growth and explore the optimal range of urinary iodine concentration(UIC) during pregnancy. Methods Pregnant women from Tanggu, Tianjin and Wuqiang, Hebei were recruited in this prospective cohort study, and their infant at 18-24 months were included. Blood and urine samples from each mother-infant pair were collected to determine thyroid function and UIC. Infants weight, length and head circumference were measured. Results From Mar 2016 to Dec 2018, 469 mother-infant pairs were enrolled totally, including 245 boys(52.2%) and 224 girls(47.8%). Maternal and infants median UIC was 161(111, 251) μg/L and 217(121, 361) μg/L, respectively, both suggesting iodine sufficiency according to WHO/UNICEF/ICCIDD-recommended criteria. Only the head circumference for age(HFA) Z-scores in infants with UIC 100-149 μg/L during pregnancy was above zero, and higher than those with UIC<100μg/L and 150-249μg/L(all P<0.05). No differences were found in Z-scores of length-for-age, weight-for-age and weight-for-length in infants with different maternal UIC during pregnancy, and no association was found between maternal thyroid function and infants physical growth. Conclusion The HFA Z-scores was higher in infants with maternal UIC 100-149 μg/L, rather than 150-249μg/L, which imply that the criteria recommended by WHO/UNICEF/ICCIDD may be a little high for Chinese pregnant women in such background of iodine nutrition.

关键词： Urinary iodine concentration Pregnant women Infants Physical growth

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三疣梭子蟹养殖技术之三三疣梭子蟹中试生产繁育技术

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中国水产 2006年第7期 45-48页

作者：陈燕婷福建省水产技术推广总站 350003

近年来,由于海洋渔业资源结构的变化,三疣梭子蟹海捕资源急剧衰退,商品价值倍增,人工养殖迅速兴起.目前,三疣梭子蟹的苗源绝大部分依靠自然海区捕捞苗种,个体大小差异很大,相互残食现象十分明显,相应地加大了养殖难度.为了促进三疣梭子... 详细信息

近年来,由于海洋渔业资源结构的变化,三疣梭子蟹海捕资源急剧衰退,商品价值倍增,人工养殖迅速兴起.目前,三疣梭子蟹的苗源绝大部分依靠自然海区捕捞苗种,个体大小差异很大,相互残食现象十分明显,相应地加大了养殖难度.为了促进三疣梭子蟹养殖产业化发展,从2002年开始,我们在福建省连江县大官坂垦区进行三疣梭子蟹池塘人工规模化育苗与养殖试验,获得成功,并取得了显著的社会效益和经济效益.

关键词：三疣梭子蟹繁育技术中试生产人工养殖资源结构产业化发展规模化育苗海洋渔业商品价值个体大小

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