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农业环境科学学报 2019年第7期38卷 1541-1549页

作者：李进芳柴延超陈顺涛单军颜晓元中国科学院南京土壤研究所土壤与农业可持续发展国家重点实验室南京210008 中国科学院大学北京100049 中国药科大学南京210009

:为了在同一体系下区分和测定水稻土反硝化、厌氧氨氧化(Anammox)和硝酸根异化还原成铵(DNRA)过程发生速率和相互关系,并获取近似原位情况下的净脱氮速率,本研究通过将15NH4^+化学氧化法测定DNRA速率和添加尿素模拟原位土柱测定净脱氮... 详细信息

:为了在同一体系下区分和测定水稻土反硝化、厌氧氨氧化(Anammox)和硝酸根异化还原成铵(DNRA)过程发生速率和相互关系,并获取近似原位情况下的净脱氮速率,本研究通过将15NH4^+化学氧化法测定DNRA速率和添加尿素模拟原位土柱测定净脱氮速率与膜进样质谱法(MIMS)进行联用,完善了一套基于膜进样质谱法(MIMS)的稻田硝态氮转化测定方法体系,利用该方法测定了5种典型的水稻土[辽宁营口(YK)、江苏宜兴(YX)、浙江金华(JH)、广西桂林(GL)和四川广安(GA)]的反硝化、Anammox、DNRA和净脱氮4种氮转化速率。结果显示:基于MIMS的方法体系可实现对水稻土中反硝化、Anammox、DNRA和净脱氮速率的测定,5种水稻土反硝化、Anammox、DNRA和净脱氮速率范围分别为(358.63±2..37)^(479.96±2..12.、(-14.81±0.2.)^(5.2.±1.2.)、(2..76±12.71)^(109.87±3.88)g N·hm^-2.h^-1和(33.33±11.16)^(72.74±14.18)g N·hm^-2.h^-1,相关结果与其他方法研究结果具有可比性。相关性分析显示:水稻土NO-3、可溶性有机碳(DOC)和土壤Fe^2.含量是反硝化过程的主要限制因素;NO3-是Anammox的关键限制因素;而土壤DOC和Fe^2.含量是DNRA过程的主要限制因素。基于MIMS的方法体系可以在短时间内(1周)测定水稻土四种厌氧氮转化速率,且所需样品量低、精确度高,在稻田或湿地土壤厌氧氮转化过程研究中有很好的应用前景。

关键词：水稻土 15N示踪反硝化厌氧氨氧化硝酸根异化还原成铵

我国典型省份小麦和玉米农田化学氮肥施用与生产运输过程的温室气体排放量估算

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农业环境科学学报 2019年第3期38卷 707-713页

作者：柴如山王擎运叶新新马超屠人凤郜红建农田生态保育与污染防控安徽省重点实验室安徽农业大学资源与环境学院合肥230036 中国农业科学院农业资源与农业区划研究所/耕地培育技术国家工程实验室北京100081

基于相关统计数据,通过文献调研方法,估算了我国河南、河北和山东3个典型省份在小麦和玉米上消费的化学氮肥产生的温室气体排放量,包括化学氮肥施用产生的土壤N_2.直接排放、通过挥发沉降和淋溶径流途径损失的氮素导致的N_2.间接排放以... 详细信息

基于相关统计数据,通过文献调研方法,估算了我国河南、河北和山东3个典型省份在小麦和玉米上消费的化学氮肥产生的温室气体排放量,包括化学氮肥施用产生的土壤N_2.直接排放、通过挥发沉降和淋溶径流途径损失的氮素导致的N_2.间接排放以及不同种类化学氮肥在生产和运输过程中的温室气体排放。结果表明:河南、河北和山东3个典型省份在小麦上消费的化学氮肥产生的温室气体排放量分别为1536万、847万、1153万t CO_2.eq·a–1,单位播种面积温室气体排放量分别为2.85、3.61、3.09 t CO_2.eq·hm–2.a–1,单位产量温室气体排放量分别为0.46、0.60、0.51 t CO_2.eq·t^(–1)·a^(–1);相应省份在玉米上消费的化学氮肥产生的温室气体排放量分别为717万、72.万、912.t CO_2.eq·a–1,单位播种面积温室气体排放量分别为2.19、2.2.、2.92.t CO_2.eq·hm–2.a–1,单位产量温室气体排放量分别为0.40、0.43、0.46 t CO_2.eq·t^(–1)·a^(–1)。研究表明,化学氮肥消费带来的温室气体排放主要来自于化学氮肥在生产过程中的温室气体排放以及化学氮肥施用导致的土壤N_2.直接排放这两部分。

关键词：小麦玉米化学氮肥 N2. 温室气体排放

Plasmon-driven reaction controlled by the number of graphene layers and localized surface plasmon distribution during optical excitation

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Light(Science & Applications) 2015年第1期4卷 137-143页

作者： Zhi-gao Dai Xiang-heng Xiao Wei Wu Yu-peng Zhang Lei Liao Shi-shang Guo Jian-jian Ying Chong-xin shan Meng-tao Sun Chang-zhong Jiang Department of physics and key {2. of Artificial Micro-and Nano-structures of the Ministry of Education Hubei Nuclear Solid Physics Key LaboratoryWuhan UniversityWuhan 430072China laboratory of Functional Nanomaterials and Printed Electronics School of Printing and PackagingWuhan UniversityWuhan 430072China State key laboratory of Luminescence and Applications Changchun Institute of OpticsFine Mechanics and PhysicsChinese Academy of SciencesChangchun 130033China School of Physical Engineering Zhengzhou UniversityZhengzhou 450052China beijing National laboratory for Condensed Matter {2. Institute of PhysicsChinese Academy of SciencesBeijing 100190China

Graphene-plasmonic hybrid platforms have attracted an enormous amount of interest in surface-enhanced Raman scattering(SERS);however,the mechanism of employing graphene is still ambiguous,so clarification about the complex interaction among molecules,graphene,and plasmon processes is urgently *** report that the number of graphene layers controlled the plasmon-driven,surface-catalyzed reaction that converts para-aminothiophenol(PATP)-to-p,p'-dimercaptoazobenzene(DMAB)on chemically inert,graphene-coated,silver bowtie nanoantenna *** catalytic reaction was monitored by SERS,which revealed that the catalytic reaction occurred on the chemical inertness monolayer graphene(1G)-coated silver *** introduction of 1G enhances the plasmon-driven surface-catalyzed reaction of the conversion of PATP-to-p,p'-*** chemical reaction is suppressed by bilayer *** the process of the catalytic reaction,the electron transfer from the PATP molecule to 1G-coated silver ***,the transferred electrons on the graphene recombine with the hot-hole produced by the localized surface plasmon resonance of silver ***,a couple of PATP molecules lost electrons are catalyzed into the p,p'-DMAB molecule on the graphene *** experimental results were further supported by the finite-difference time-domain method and quantum chemical calculations.

关键词： graphene graphene-mediated SERS plasmon-driven reaction SERS

Isolation and characterization of three pairs of verrucosidin epimers from the marine sediment‑derived fungus Penicillium cyclopium and confguration revision of penicyrone A and related analogues

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Marine Life Science & Technology 2023年第2期5卷 223-231页

作者： Yan-He Li Attila Mándi Hong-Lei Li Xiao-Ming Li Xin Li Ling-Hong Meng Sui-Qun Yang Xiao-shan Shi Tibor Kurtán Bin-Gui Wang CAS and shandong Province key {2. of Experimental Marine Biology Institute of OceanologyChinese Academy of Sciencesand Laboratory of Marine Biology and Biotechnology at the Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China School of Marine Science University of Chinese Academy of SciencesBeijing 100049China Department of Organic Chemistry University of DebrecenEgyetem Tér 1Debrecen 4032Hungary Center for Ocean Mega-Science Chinese Academy of SciencesQingdao 266071China

Verrucosidins,a methylatedα-pyrone class of polyketides rarely reported upon,have been implicated in one or more neurological *** the signifcance of verrucosidins as neurotoxins,the absolute confgurations of most of the derivatives have not been accurately characterized *** this study,three pairs of C-9 epimeric verrucosidin derivatives,including the known compounds penicyrones A and B(1a/1b)and 9-O-methylpenicyrones A and B(2./2.),the new compounds 9-O-ethylpenicyrones A and B(3a/3b),together with the related known derivative verrucosidin(4),were isolated and identifed from the culture extract of Penicillium cyclopium SD-413,which was obtained from the marine sediment collected from the East china *** structures were established based on an in-depth analysis of nuclear magnetic resonances(NMR)and mass spectroscopic *** of the absolute confgurations of these compounds was accomplished by Mosher’s method and time-dependent density functional theory(TDDFT)calculations of electronic circular dichroism(ECD)and optical rotation(OR).The confgurational assignment of penicyrone A demonstrated that the previously reported C-6 absolute confguration of verrucosidin derivatives needs to be revised from(6S)to(6R).The 9R/9S epimers of compounds 1–3 were found to exhibit growth inhibition against some pathogenic bacteria,indicating that they have potential as lead compounds for the creation of antimicrobial agents.

关键词： Marine-derived fungus Penicillium cyclopium Verrucosidin derivatives TDDFT-ECD calculations Mosher’s method Antimicrobial activity

Reevaluation of thermonuclear reaction rate of ^(50)Fe(p,γ)^(51)Co

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chinese physics C 2016年第12期40卷 113-119页

作者： Li-Ping Zhang Jian-Jun He Wan-Dong chai Su-Qing Hou Li-Yong Zhang College of physics and Electronic Information Engineering Chifeng University Chifeng 024000 China key laboratory of Optical Astronomy National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China institute of Modern physics Chinese Academy of Sciences

The thermonuclear rate of the 50Fe（p, γ）51Co reaction in the Type I X-ray bursts （XRBs） temperature range has been reevaluated based on a recent precise mass measurement at CSRe Lanzhou, where the proton separa- tion energy Sp=142.77 keV has been determined firstly for the ~1Co nucleus. Comparing to the previous theoretical predictions, the experimental Sp value has much smaller uncertainty. Based on the nuclear shell model and mirror nuclear structure information, we have calculated two sets of thermonuclear rates for the 50Fe（p, γ）51Coreaction by utilizing the experimental Sp value. It shows that the statistical-model calculations are not ideally applicable for this reaction primarily because of the low density of low-lying excited states in 51Co. In this work, we recommend that a set of new reaction rates based on the mirror structure of 51Cr should be incorporated in future astrophysical network calculations.

关键词： X-ray burst (XRB) nucleosynthesis mass measurement proton separation energy reaction rate

Elastic scattering of ^(13)C and ^(14)C isotopes on a ^(2.8)Pb target at energies of approximately five times the Coulomb barriers

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chinese physics C 2024年第3期48卷 65-71页

作者：杨过段芳芳王康杨彦云孙志宇 Valdir Guimarães 庞丹阳陈文棣金磊许世伟马军兵马朋白真汪凌昊刘泉王惠仁吕冰锋郭松 Mukhi Kumar Raju 王秀华李荣华张玉虎周小红胡正国徐瑚珊 CAS key laboratory of {2. Precision nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100080China Instituto de Física Universidade de São PauloRua do Matão1371São Paulo 05508-090SPBrazil School of physics and beijing {2. laboratory of Advanced nuclear Materials and physics Beihang UniversityBeijing 100191China School of physics Science and Engineering Tongji UniversityShanghai 200092China School of physics and Optoelectronic Engineering Anhui UniversityHefei 230601China Department of physics GITAM School of ScienceGITAM UniversityVisakhapatnam 530045India

The elastic scattering angular distributions of ^(13)C at 340 MeV and ^(14)C at 2.4 MeV and 342.MeV on a ^(2.8)Pb target,which correspond to approximately five times the Coulomb barriers,were measured at the Radioactive Ion Beam Line in *** data were analyzed within the optical model and continuum-discretized coupled-channels(CDCC)framework,and the results of both calculations could effectively account for the experimental *** differential cross sections of elastic scattering revealed no particular suppression at the Coulomb nuclear interference peak angles,suggesting that the breakup coupling effects on the elastic scattering angular distributions were negligibly small in this incident energy *** contributions from the couplings with inelastic states to the elastic cross sections were of minor importance within the angular range covered by these experiments.

关键词： elastic scattering radioactive ion beam angular distribution optical model coupling effects

Efficacious selective separation of U(Ⅵ) over Mo(Ⅵ) using novel 2.9-diamide-1,10-phenanthroline ligands: Liquid-liquid extraction and coordination chemistry

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chinese Chemical Letters 2023年第11期34卷 163-168页

作者： Taoyuan Xiu Simei Zhang Peng Ren Siyan Liu Shuai Wang Hamza Shehzad Jingyang Wang Meng Zhang Guoan Ye Caishan Jiao Qunyan Wu Liyong Yuan Zhifang chai Weiqun Shi College of nuclear Science and Technology Harbin Engineering UniversityHarbin 150001China laboratory of nuclear Energy Chemistry Institute of High Energy PhysicsChinese Academy of SciencesBeijing 100049China china institute of Atomic Energy Beijing 102413China State key laboratory of {2. Resources and Environment School of Nuclear Science and TechnologyEast China University of TechnologyNanchang 330013China School of Chemistry University of the PunjabLahore 54590Pakistan

Uranium and molybdenum are important strategic elements. The production of ^(99)Mo and the hydrometallurgical process of uranium ore face difficult problems of separation of uranium and *** this study, the four phenanthroline diamide ligands were synthesized, and extraction and stripping experiments were performed under different conditions to evaluate the potential application of these ligands for separation of U(Ⅵ) over Mo(Ⅵ). With the growth of alkyl chain, the solubility of ligands could be greatly improved, and the separation effect of U(Ⅵ) over Mo(Ⅵ) gradually increased. The SF_(U/Mo) were around 10,000 at 4 mol/L HNO3. Three stripping agents were tested with the stripping efficiency of Na_(2.CO_(3)(5%) > H_(2.O > HNO_(3)(0.01 mol/L). The stripping percentages of the three stripping agents were all close to unity, indicating that the ligands had the potential to be recycled. The chemical stoichiometry of U(Ⅵ) complexes with ligands was evaluated as 1:1 using electrospray ionization mass spectrometry,ultraviolet visible spectroscopy and single-crystal X-ray diffraction. The consistency between theoretical calculation and experimental results further explains the coordination mechanism.

关键词： Phenanthroline diamide ligand Uranium Molybdenum Solvent extraction Coordination chemistry

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低氧诱导因子-1与低氧训练的调控机制

北京体育大学学报 2005年第9期28卷 1227-1229页

作者：毛杉杉潘同斌王瑞元北京体育大学北京100084 扬州大学体育学院江苏扬州225000

低氧诱导因子-1(hypoxia inducible factor-1,HIF-1)作为低氧诱导的核转录因子,通过对低氧反应基因(hypoxia responsive genes,HRGs)的转录调控,在分子水平上介导了细胞乃至器官系统对低氧的反应。就HIF-1的结构、低氧时(在哺乳动物组织... 详细信息

低氧诱导因子-1(hypoxia inducible factor-1,HIF-1)作为低氧诱导的核转录因子,通过对低氧反应基因(hypoxia responsive genes,HRGs)的转录调控,在分子水平上介导了细胞乃至器官系统对低氧的反应。就HIF-1的结构、低氧时(在哺乳动物组织中)表达部位的广泛性和低氧反应应答中HIF-1的表达以及与低氧训练的可能的分子机制进行了综述:HIF-1可能在启动或逆转组织对各种低氧、训练的适应或适应不良反应中起重要作用。

关键词： HIF-1 低氧训练机制

Study of the decorporation efficacy and toxicity of tetradentate 3-hydroxy- 2.pyridinone ligands at the cellular level

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Radiation Medicine and Protection 2020年第4期1卷 159-165页

作者： Xiaomei Wang Cen Shi Manni Gao Ying Xu Yang Jiao Jianmei Wan Jianping Cao Zhifang chai Juan Diwu State key laboratory of Radiation Medicine and Protection School for Radiological and Interdisciplinary Sciences(RAD-X)Collaborative Innovation Center of Radiation Medicine of Jiangsu Higher Education InstitutionsSoochow UniversitySuzhou215123China beijing nuclear Industry Hospital-Fang{2. Campus Beijing102413China

Objective:A series of experiments were carried out to study the comparative decorporation efficacy and toxicity of three tetradentate hydroxypyridinone ligands(3LI-1-Cm-3,2.HOPO,5LIO-1-Cm-3,2.HOPO,and 7LIO-1-Cm-3,2.HOPO)with the variation of the linker length and the ***:Three ligands were obtained from a 4-step synthesis via the amidation of HOPO unit and different *** titrations were carried out to evaluate the formation constants of their corresponding uranyl ***-8 and colony formation assays were used to compare the cytotoxicity of the three ligands and uranyl using renal proximal tubular epithelial(NRK-52.)*** vitro uranium removal assays were performed to assess decorporation efficiencies of those ligands by co-incubating uranium and chelators with NRK-52. cells for 48 ***:Among the three ligands,5LIO-1-Cm-3,2.HOPO exhibits the highest uranyl affinity(logβ110?18.6(7))in comparison to the other two ligands(logβ110?14.9(2.for 3LI-1-Cm-3,2.HOPO and logβ110?16.7(1)for 7LIO-1-Cm-3,2.HOPO).The results of CCK-8 tests and colony formation assays further elucidate that 5LIO-1-Cm-3,2.HOPO and 7LIO-1-Cm-3,2.HOPO both show a similar level of cytotoxicity compared with ZnNa3-DTPA at relatively low ligand *** contrast,in the 3LI-1-Cm-3,2.HOPO treated group,the cell viability decreased markedly with the increase of the ligand concentrations,and the colony formation capability of NRK-52. cells was ***,the comparative decorporation efficacy of the three ligands was obtained from in vitro uranium removal assays,suggesting that these ligands could significantly inhibit the cellular uptake and prompt the cellular release of uranium from NRK-52. cells by the level of 81.9%,91.8%,and 87.1%,***:Our current results demonstrate that the linker/backbone species would significantly affect the decorporation efficacy and toxicity of the tetradentate 3-hydroxy-2.pyridinone ligands

关键词： Uranium Hydroxypyridinone Decorporation efficacy Cytotoxicity Metal complexation