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Sedimentary record of climate change in a high latitude fjord—Kongsfjord

Acta Oceanologica sinica 2023年第1期42卷 91-102页

作者： Hang wu Binbin Deng Jinlong Wang sheng Zeng Juan Du Peng Yu Qianqian Bi Jinzhou Du State Key Laboratory of Estuarine and Coastal Research East China Normal UniversityShanghai200241China Monitoring Center of Aquatic Environment of Pearl River Basin Guangzhou510611China Research Centre for Eco-Environmental Engineering Dongguan University of TechnologyDongguan523808China Big Data institute of Digital Natural Disaster Monitoring in Fujian Xiamen University of TechnologyXiamen361024China

The sedimentary record of climate change in the Arctic region is useful for understanding global *** is located in the subpolar region of the Arctic and is a suitable site for studying climate *** retreat is occurring in this region due to climate change,leading to an increase in meltwater outflow with a high debris *** August 2017,we collected a sediment Core Z3 from the central fjord near the Yellow River ***,we used the widely used chronology method of 210Pb,^(137)Cs,and other parameters to reflect the climate change record in the sedimentary environment of *** results showed that after the mid-late 1990s,the mass accumulation rate of this core increased from 0.10 g/(cm^(2)·a)to 0.34 g/(cm^(2)·a),while the flux of^(210)Pb_(ex)increased from 125 Bq/(m^(2)·a)to 316 Bq/(m^(2)·a).The higher sedimentary inventory of^(210)Pb_(ex)in Kongsfjord compared to global fallout might have been caused by sediment focusing,boundary scavenging,and riverine *** between the inventory of^(137)Cs and global fallout indicated that terrestrial particulate matter was the main source of^(137)Cs in fjord *** sedimentation rate increased after 1997,possibly due to the increased influx of glacial meltwater containing *** addition,the^(137)Cs activity,percentage of organic carbon(OC),and OC/total nitrogen concentration ratio showed increasing trends toward the top of the core since 1997,corresponding to a decrease in the mass balance of glaciers in the *** results ofδ^(13)C,δ^(15)N and OC/TN concentration ratio showed both terrestrial and marine sources contributed to the organic matter in Core *** relative contribution of terrestrial organic matter which was calculated by a two-endmember model showed an increased trend since *** these data indicate that global climate change has a significant impact on Arctic glaciers.

关键词： Kongsfjord radionuclide organic carbon/total nitrogen(OC/TN)concentration ratio δ^(13)C δ^(15)N sediment record climate change

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Composition, source, mass closure of PM_(2.5) aerosols for four forests in eastern China

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Journal of Environmental Sciences 2010年第3期22卷 405-412页

作者： Li Li wu Wang Jialiang Feng Dongping Zhang Huaijian Li Zeping Gu Bangjin Wang guoying sheng Jiamo Fu institute of Environmental Pollution and health School of Environmental and Chemical Engineering Shanghai University Shanghai 200444 China. College of Resources and Environment Sichuan Agricultural University Ya'an 625014 China State Key Laboratory of organic Geochemistry Guangzhou Institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

PM2.5 aerosols were collected in forests along north latitude in boreal-temperate, temperate, subtropical and tropical climatic zones in eastern China, i.e., Changbai Mountain Nature Reserve （CB）, Dongping National Forest Park in Chongming Island （CM）, Dinghu Mountain Nature Reserve （DH）, Jianfengling Nature Reserve in Hainan Island （HN）. The mass concentrations of PM2.5, organic carbon （OC）, elemental carbon （EC）, water soluble organic carbon （WSOC） as well as concentrations of ten inorganic ions （F？, Cl？, NO3？, SO42？, C2O42？, NH4＋, Na＋, K＋, Ca2＋, Mg2＋） were determined. Aerosol chemical mass closures were achieved. The 24-hr average concentrations of PM2.5 were 38.8, 89.2, 30.4, 18 μg/m3 at CB, CM, DH and HN, respectively. organic matter and EC accounted for 21%–33% and 1.3%–2.3% of PM2.5 mass, respectively. The sum of three dominant secondary ions （SO42-, NO3-, NH4＋） accounted for 44%, 50%, 45% and 16% of local PM2.5 mass at CB, CM, DH and HN, respectively. WSOC comprised 35%–65% of OC. The sources of PM2.5 include especially important regional anthropogenic pollutions at Chinese forest areas.

关键词： PM2.5 aerosols forests OC/EC WSOC inorganic ions

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美登素全合成的研究 Ⅰ.C1—C8片段的立体选择性合成

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化学学报 1980年第5期 502-506页

作者：潘百川张红潘纯英舒韫王照福高怡生中国科学院上海药物研究所上海第十二制药厂

美登素（Maytansine 1）系从美登木（Maytenus ovatus）中分得,极低剂量就对多种动物肿瘤有明显抑制作用。我国亦从云南美登木（Maytenus hookeri）中分得美登素。1是十九员柄型大环内酰胺,有八个手性碳原子和两个反式共轭双键,各国化... 详细信息

美登素（Maytansine 1）系从美登木（Maytenus ovatus）中分得,极低剂量就对多种动物肿瘤有明显抑制作用。我国亦从云南美登木（Maytenus hookeri）中分得美登素。1是十九员柄型大环内酰胺,有八个手性碳原子和两个反式共轭双键,各国化学家对其全合成已作了许多工作。本文报道C1—C8片段2的合成。片段中包含五个手性碳原子,由核磁共振、反应机制等推断其绝对构型与美登素一致。

关键词：全合成立体选择性二甲基二烷基 C1 美登素 OCH 绝对构型多峰沸点核磁共振核自旋共振单峰

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A Triptycene-Based Porous organic Polymer that Exhibited High Hydrogen and Carbon Dioxide Storage Capacities and Excellent CO_(2)/N_(2) Selectivity

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中国化学:英文版 2015年第5期33卷 539-544页

作者： Xi-Long Lu Tian-You Zhou Doufeng wu Qiang Wen Xin Zhao Qiaowei Li qun Xiang Jia-Qiang Xu Zhan-Ting Li Department of chemistry Shanghai UniversityShanghai 200444China Key Laboratory of Synthetic and Self-Assembly chemistry for organic Functional Molecules Shanghai Institute of Organic ChemistryChinese Academy of SciencesShanghai 200032China Department of chemistry Fudan UniversityShanghai 200433China

A novel porous organic polymer(POP)has been constructed through the condensation of triptycene tricatechol and 1,3,5-benzenetris(4-phenylboronic acid).This triptycene-based POP exhibited high H2 uptake(up to 1.84 wt%at 77 K,1 bar),large CO_(2) adsorption capacity(up to 18.1 wt%at 273K,1 bar),and excellent CO_(2)/N_(2) adsorption selectivity(up to 120/1).The influence of solvent on the gas adsorption performance of the POP has also been investigated.

关键词： porous organic polymers H_(2)/CO_(2)adsorption CO_(2)/N_(2)selectivity

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碱金属萃取化学的研究 Ⅲ.弱酸性偶氮螯合剂化学结构对萃取锂的性能影响

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化学学报 1983年第2期41卷 153-160页

作者：严金英李树森冯涵真程德凯金慕军陈燿焕盛怀禹中国科学院上海有机化学研究所

本文通过对-取代苯基偶氮-2-萘酚及邻-取代苯基偶氮-芳香酚两种类型共十一种螯合剂与TOPO（或TRPO）协草锂的性能研究及HMO计算,讨论了该类螫合剂与中性协萃剂协萃锂时的结构效应。结果表明:（1）对-取代苯基偶氮-2-萘酚类赘合剂的苯基... 详细信息

本文通过对-取代苯基偶氮-2-萘酚及邻-取代苯基偶氮-芳香酚两种类型共十一种螯合剂与TOPO（或TRPO）协草锂的性能研究及HMO计算,讨论了该类螫合剂与中性协萃剂协萃锂时的结构效应。结果表明:（1）对-取代苯基偶氮-2-萘酚类赘合剂的苯基偶氮的配键N原子的电荷密度qN与羟基氧原子的电荷密度qoH无明显变化,萃取能力只受螯合剂pKa的影响,协萃锂的表观平衡常数随整合剂pKa值的下降而上升;（2）邻苯基偶氮-芳香酚类螯合剂由HMO计算表明,它们的羟基氧原子的电荷密度qoH、配键N原子的电荷密度qN及pka值都发生明显的变化,它们与TRPO的协萃能力随配键强度的增加而上升,并随PKa值的上升而下降,其中最合适的结构是1-OH-2-（C6H5N=N）-C10H6,它的Pka值较小,qN适中,所以协萃能力最大。相反,1-（C6H5N=N）-8-OH-C10H6的qN最小,pKa居中,协萃能力最小;（3）螯合物的稳定性主要由配键控制。因此,以螯合物分子的内氢键强度ΔδoH来量度配键强度,发现螯合剂萃取锂的分配系数随其分子的ΔδOH/pka值的增大而递增。

关键词：偶氮电荷密度氧原子电性分析试剂螯合剂鳌合剂萃取能力弱酸性碱金属

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Mixing State of Particles by Single Particle Aerosol Mass Spectrometer in Urban Area of PRD

Mixing State of Particles by Single Particle Aerosol Mass Sp...

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第七届亚洲气溶胶会议

作者： Xinhui Bi 1, guohua Zhang1, Lei Li 2, Xinming Wang 1, guoying sheng 1, Jiamo Fu 1, 2 and Zhen Zhou2 1 State Key Laboratory of organic Geochemistry, Guangdong Province Key Laboratory of Utilization and Protection of Environmental Resource, Guangzhou institute of Geochemistry, Chinese Academy of Sciences, Guangzhou, 510640, P.R. China 2 School of Environmental and Chemical Engineering, shanghai University, shanghai 200444, P. R. China

Single particle aerosol mass spectrometer (SPAMS) was used to characterize the single particle size and chemical composition of submicron aerosols in the urban area of the Pearl River Delta (PRD) region, China, for the period April 30 through May 22, 2010. This is the first study for the mixing state of aerosols by direct observation in this region. 696,465 particles were sized and chemical analyzed with both positive and negative ion spectra, in which 141,338 biomass burning particles were identified representing a significant source of submicron particles ～20.3% by numbe, and carbonaceous particles accounted for as much as 5% of submicron particles by number. Up to 98% carbonaceous particles were found to internally mix with secondary inorganic species. Carbonaceous particles were clustered into three distinct particle groups, comprised of organic carbon (OC), elemental carbon (EC) and the mixture of both (OCEC). The OC specie was the most abundant, with concentrations of 43%. EC and OCEC followed with 32% and 25%, respectively. Nitrate and ammonium traces between particle groups had negligible variance, while sulfate was found to prefer to associate with OC and OCEC rather than EC. The influence of aerodynamic diameter was substantial for mixing states with nitrate and ammonium, with ratios lower in the condensation mode than droplet mode;whereas sulfate mixing ratios were nearly constant within 0.2-1.2 μm. Biomass burning particles were clustered into six distinct particle groups, comprising of Ca-rich, Na-rich, organic carbon (OC), elemental carbon (EC), the mixture of OC and EC (OCEC) and Secondary. OC was the largest contributor with a fraction of 22.9%, followed by Secondary type (21.4%) and OCEC (19.0%). Na-rich type was observed in 11.9% of the particles and 90% internally mixed with EC. The fraction of nitrate in biomass burning particles was higher 10% than in carbonaceous particles, which could be explained by the fact that the rich sodium and potassium

关键词： Biomass burning carbonaceous aerosol mixing state single particle nitrate sulfate SPAMS ATOFMS aerosol PRD.

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SAPT:a synchrotron-based proton therapy facility in shanghai

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Nuclear Science and Techniques 2023年第10期34卷 36-46页

作者： Man-Zhou Zhang De-Ming Li Li-Ren Shen Hai-Rong Zhang Zhi-Ling Chen Han-Wen Du Ming Gu Rui Li De-Kang Liu Yue-Hu Pu Jun-Feng Yu Jian-Feng Chen Chu Chen Chun-Long guo Hao guo Ge-Yang Jiang Zhi-Qiang Jiang Lin Jin Wen-Jing Li Xiu-Fang Li Ye Lin Ming Liu Yong-Hao Liu Ya-Juan Liu Ming Lv Qing-Ru Mi Lian-Hua Ouyang Wei-guo Shi Hang Shu Qi-sheng Tang Kun Wang Zhi-Shan Wang Jun wu Xiao-Bing wu Jia-Qiang Xu Wen-Zhen Xu Chong-Xian yin Cheng Yu Ren-Xian Yuan Qi-Bing Yuan Hai-qun Zhang Miao Zhang Wen-Zhi Zhang Li-ying Zhao Wei-Min Zhou Shou-Xian Fang Xi-Dong Sun Zhen-Tang Zhao shanghai institute of Applied Physics Chinese Academy of SciencesShanghai 201800China shanghai Advanced Research institute Chinese Academy of SciencesShanghai 201204China APACTRON Particle Equipment Co. Ltd.Shanghai 201815China The institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Because of its excellent dose distribution,proton therapy is becoming increasingly popular in the medical application of cancer treatment.A synchrotron-based proton therapy facility was designed and constructed in *** synchrotron,beam delivery system,and other technical systems were commissioned and reached their expected *** a clinical trial of 47 patients was finished,the proton therapy facility obtained a registration certificate from the National Medical Products *** characteristics of the accelerator and treatment systems are described in this article.

关键词： Proton therapy Synchrotron Slow extraction Gantry Beam delivery system

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常压室温等离子体(ARTP)诱变对凡纳对虾不同家系幼体发育及仔虾抗逆性状的影响

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渔业科学进展 2024年第6期45卷 144-154页

作者：周静心孟宪红傅强曹宝祥陈宝龙刘绵宇曹家旺李旭鹏强光峰代平栾生邢群李色东孔杰中国水产科学研究院黄海水产研究所、海水养殖生物育种与可持续产出全国重点实验室山东青岛266071 青岛海洋科技中心海洋渔业科学与食物产出过程功能实验室山东青岛266237 上海海洋大学水产科学国家级实验教学示范中心上海201306 邦普种业科技有限公司山东潍坊261311 广东恒兴饲料实业股份有限公司广东湛江524000

为研究物理诱变对虾类前期幼体发育及抗逆性状的影响,探讨通过诱变技术增加选育群体遗传多样性和可利用遗传变异的可行性,本研究利用常压室温等离子体(ARTP)诱变技术对4尾来自不同家系(A、B、C和D)的凡纳对虾(Penaeus vannamei)个体所... 详细信息

为研究物理诱变对虾类前期幼体发育及抗逆性状的影响,探讨通过诱变技术增加选育群体遗传多样性和可利用遗传变异的可行性,本研究利用常压室温等离子体(ARTP)诱变技术对4尾来自不同家系(A、B、C和D)的凡纳对虾(Penaeus vannamei)个体所产的受精卵(原肠胚期)分别进行相同功率(360 W)、不同时间(2、4、8和12 min)的批量诱变处理,并对孵化率、肢芽期孵化畸形率、存活率、变态率以及仔虾低氧耐受性和氨氮胁迫指标进行分析。结果显示,ARTP对凡纳对虾进行诱变处理后在不同家系间有一些共性的规律,在幼体发育前期阶段,4个家系随着诱变时间的增加,肢芽期畸形率均呈上升趋势,孵化率均呈下降趋势;与未经过诱变的对照组相比,除A和D家系诱变2 min组外,其余处理组肢芽期孵化畸形率均显著升高(P<0.05);除A家系诱变2 min组外,其余各家系处理组孵化率均显著降低(P<0.05);肢芽期孵化畸形率和孵化率与诱变时间均呈现中度或高度相关;与对照组相比,A、B、C和D4个家系在相同阶段的同一处理组存活率的表现具有不定向性,A家系诱变8min组存活率显著降低(P<0.05),而C家系诱变4和8min组存活率显著升高,D家系诱变2和4 min组存活率显著降低,而诱变8 min组则显著升高。可能是诱变的不定向性以及诱变作用于个体造成的。通过存活率和各期变态率综合分析可得,低剂量(2min组)诱变死亡高峰期多发生于幼体发育后期,高剂量(4、8和12min组)诱变幼体死亡高峰期多发生于幼体发育中前期。对A家系幼体的低氧耐受性和氨氮胁迫测试结果表明,低剂量的辐射可能会在一定程度上提高低氧耐受能力;诱变2 min组和8 min组分别在氨氮胁迫实验第4天、第7天存活率很高,诱变对该家系幼体对抗氨氮胁迫的能力有一定的影响。说明ARTP诱变凡纳对虾受精卵在不同家系中幼体发育前期具有一些共性趋势,在幼体发育后期和性状的改变上具有不定向性。研究结果对凡纳对虾新种质创制及功能研究材料的制备提出了新的方法,并为凡纳对虾诱变育种提供了基础数据和科学依据。

关键词：凡纳对虾诱变育种 ARTP 幼体发育

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β-双酮系化合物的核磁共振谱研究

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化学学报 1980年第4期 351-357页

作者：朱自莹李蓓莉袁群龙海燕叶伟贞孙桂云程德凯严亦君盛怀禹中国科学院上海有机化学研究所

本文研究了二十六种β-双酮系化合物的核磁共振谱。分析讨论了主要基团的化学位移。还讨论了中两个甲基在化学上不等性是由于结构呈晾式,而不是呈偶氮式。从3-位质子的化学位移分析表明,R1、R2和R3的电负性是影响3-位质子化学位移的主... 详细信息

本文研究了二十六种β-双酮系化合物的核磁共振谱。分析讨论了主要基团的化学位移。还讨论了中两个甲基在化学上不等性是由于结构呈晾式,而不是呈偶氮式。从3-位质子的化学位移分析表明,R1、R2和R3的电负性是影响3-位质子化学位移的主要原因,空间效应则是很小的。我们认为R1、R2和R3的电负性和空间效应对烯醇化都有显著作用。最后,讨论了实验结果与Shapet’ko计算结果的一致性和烯醇化的方向性,并用Shapet’ko的结果推算出一些化合物中R3对δOH的贡献。

关键词：化学位移 ppm CO 基团谱线位移核磁共振核自旋共振化合物低场烯醇化质子共振

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Graphene foam/hydrogel scaffolds for regeneration of peripheral nerve using ADSCs in a diabetic mouse model

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Nano Research 2022年第4期15卷 3434-3445页

作者： qun Huang Yuting Cai Xinrui Yang Weimin Li Hongji Pu Zhenjing Liu Hongwei Liu Mohsen Tamtaji Feng Xu Liyuan sheng Tae-Hyung Kim Shiqing Zhao Dazhi Sun Jinbao Qin Zhengtang Luo Xinwu Lu Department of Vascular Surgery Shanghai Ninth People’s HospitalShanghai Jiao Tong University School of MedicineShanghai 200011China Guangdong Provincial Key Laboratory of Functional Oxide Materials and Devices Department of Materials Science and EngineeringSouthern University of Science and TechnologyShenzhen 518055China Vascular Center of shanghai Jiao Tong University Shanghai 200011China Department of Chemical and Biological Engineering and William Mong Institute of Nano Science and Technologythe Hong Kong University of Science and TechnologyHong Kong 999077China Bioinspired Engineering and Biomechanics Center(BEBC) the Key Laboratory of Biomedical Information Engineering of Ministry of EducationSchool of Life Science and TechnologyXi'an Jiaotong UniversityXi'an 710049China Shenzhen institute Peking UniversityShenzhen 518057China School of Integrative Engineering Chung-Ang UniversitySeoul 06974Republic of Korea School of Biomedical Engineering Shanghai Jiao Tong UniversityShanghai 200030China

The functional recovery of peripheral nerve injury(PNI)is unsatisfactory,whereas diabetes mellitus(DM)and its related complications further attenuate the restoration of diabetic PNI(DPNI).Adipose-derived stem cells(ADSCs)are promising candidates for treatment of DPNI due to their abundant source,excellent differentiation and paracrine *** results showed that ADSCs remarkably enhanced the proliferation and migration of Schwann cells and endothelial cells,and tube ***,ADSCs could regulate Nrf2/HO-1,NF-κB and PI3K/AKT/mTOR signaling pathways,showing multiple functions in reducing oxidative stress and inflammation,and regulating cell metabolism,growth,survival,proliferation,angiogenesis,differentiation of Schwann cell and myelin *** current study,novel graphene foam(GF)/hydrogel-based scaffold was developed to deliver ADSCs for treatment of ***/hydrogel scaffold exhibited excellent mechanical strength,suitable porous network,superior electrical conductivity,and good *** vitro results revealed that GF/hydrogel scaffold could obviously accelerate proliferation of Schwann ***,in vivo experiments demonstrated that ADSCs-loaded GF/hydrogel scaffold significantly promoted the recovery of DPNI and inhibited the atrophy of targeted muscles,thus providing a novel and attractive therapeutic approach for DPNI patients.

关键词： peripheral nerve injury(PNI) diabetes mellitus(DM) adipose-derived stem cells(ADSCs) graphene hydrogel scaffold

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