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冰封-非冰封条件下达里湖TDS空间变化及影响因素

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干旱区资源与环境 2024年第8期38卷 149-158页

作者：张博尧李文宝郭鑫史玉娇杜蕾内蒙古农业大学职业技术学院包头014000 内蒙古农业大学水资源利用与保护自治区重点实验室呼和浩特010018

溶解性固体总量(TDS)是水循环过程的关键示踪剂之一。特别是寒旱区,湖泊既经历冬季冰封期,也会接受夏季集中大气降水输入,这导致不同深度湖水TDS含量对应了补给源水化学特征。基于此,文中以内蒙古达里湖为目标,持续采集了2018至2020年湖... 详细信息

溶解性固体总量(TDS)是水循环过程的关键示踪剂之一。特别是寒旱区,湖泊既经历冬季冰封期,也会接受夏季集中大气降水输入,这导致不同深度湖水TDS含量对应了补给源水化学特征。基于此,文中以内蒙古达里湖为目标,持续采集了2018至2020年湖水(冰)等样品共324个,系统分析了湖泊TDS含量的变化特征,并结合氢、氧稳定同位素(δD和δ^(18)O)变化,探讨了冰封-非冰封状态下补给源差异对TDS变化的影响。结果表明:1)冰封条件下冰中TDS含量较低(平均约213mg/L),对应冰体中δD和δ^(18)O值最富集(约-24.25‰和-1.22‰),而水体TDS含量相对较高(平均约483mg/L),但δD和δ^(18)O值相对贫化(约-33.56‰和-2.35‰);在非冰封期,TDS含量随水深增加小幅下降,而δD值和δ^(18)O值(平均值-32.375‰和-2.09‰)则比冬季水体更加富集。特别地,夏季湖水d-excess值明显偏负,显示大气降水等补给量增加。2)虽然达里湖水样中TDS与δD、δ^(18)O值变化过程相似,但是由于不同水深补给源以及外界环境条件差异导致于表层水主要受大气降水、河流输入和结冰过程等影响而深层水主要受地下水输入影响,因此造成表层水中TDS与同位素值相关性在非冰封阶段较低,而冰封条件下由于“冷冻浓缩”影响而相关性较高;而底层水受不同深度地下水补给过程差异影响,导致深水区(水深>7.0m)底层水TDS含量与同位素值的相关性在冰封-非冰封条件下均较高。特别地,达里湖TDS含量变化与d-excess值呈明显反相关系,指示蒸发和大气降水对湖泊水文化学特征的影响,进一步显示TDS含量变化受到水文循环过程的影响。

关键词： TDS 氢氧同位素补给来源冰封期达里湖

Study on the Preparation and Antileukemic Activity of New lipophilic 1-β-D-arabinofuranosylcytosine Derivatives

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Journal of Ocean University of China 2018年第2期17卷 385-391页

作者： CHU Yanyan TIAN Zhenhua HOU Yingwei li wenbao School of Medicine and Pharmacy Ocean University of ChinaQingdao 266003China Innovation Center for Marine Drug Screening and Evaluation Qingdao National Laboratory for Marine Science and TechnologyQingdao 266071China Marine Biomedical Research Institute of Qingdao Qingdao 266003China

Cytarabine(1-β-D-arabinofuranosylcytosine, Ara-C), isolated from a Caribbean sponge species Tethyacrypta, is the first antitumor drug from a marine resource. In 1980, the US Food and Drug Administration approved this drug for the treatment of different types of leukemia. This drug has a short plasma half-life, low stability, limited bioavailability, and severe side effects. To improve stability and bioavailability, we synthesized nine novel derivatives by blocking the cytarabine metabolic sites and improving lipophilicity. The c Log P values of the newly synthesized compounds were calculated. All the synthesized compounds were more lipophilic than cytarabine, resulting in membrane permeability and bioavailability improvement. The antitumor activities against leukemia cell line HL-60 were evaluated by using the MTT assay. The bioassay results revealed that the IC_(50) values of compounds 5, 8 and 9 were 0.080, 0.090 and 0.057 μmol L^(-1), respectively, which was similar with that of cytarabine(0.056 μmol L^(-1),). In comparison, compound 4 with a phosphate group at O5' was inactive. Because phosphoester bonds are easily hydrolyzed by alkaline phosphatase and are commonly used in producing prodrug strategies, compound 4 might also be metabolized in vivo and generate compound 3 or even cytarabine through a multi-step reaction. Thus, compound 4 might be a promising compound to be developed as a prodrug.

关键词： cytarabine leukemia marine drug prodrug antitumor drug

Late Quaternary ice-rafted detritus events in the Chukchi Basin, western Arctic Ocean

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Chinese Science Bulletin 2010年第4期55卷 432-440页

作者： WANG RuJian XIAO WenShen li wenbao SUN YeChen State Key Laboratory of Marine Geology Tong/i University Shanghai 200092 China Alfred Wegener Institute for Polar and Marine Research Bremerhaven 2 7517 Germany

The late Quaternary ice rafted detritus (IRD) events in the Chukchi Basin, western Arctic Ocean are indications of the provenance of the coarser detritus and ice export events, and also document the evolutionary histories of Beaufort Gyre and the North American Ice Sheet (NAIS). The sediment of core M03 from the Chukchi Basin was selected to study the regional response to the ice export events and the NAIS variability. The stratigraphic framework of M03 was established by a combination of lithological features and downcore color change cycles, AMS14C dating with foraminifera abundance and IRD events. The core was also compared with the adjacent core NWR 5 from the Northwind Ridge area. The core extends back to Marine Isotope Stage (MIS) 7. A sedimentary hiatus of 10―20 ka might occur between 16 to 20 cm core depth. Seven IRD events are distinguished from the studied core and are presented during the early MIS 1, MIS 3, MIS 5 and late MIS 7. These IRD are transported by sea ice and icebergs, which were exported to the Beaufort Sea from the M'Clure Strait Ice Stream, Canadian Arctic Archipelago, and brought to the Chukchi Basin by the Beaufort Gyre.

关键词：盆地沉积物晚第四纪北冰洋粗碎屑事件西部管理信息系统 MIS系统

Sea surface temperature and subtropical front movement in the South Tasman Sea during the last 800 ka

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Chinese Science Bulletin 2010年第29期55卷 3338-3344页

作者： li wenbao WANG RuJian XIANG Fei DING XiaoHui ZHAO MeiXun State Key Laboratory of Marine Geology Tongji University Shanghai 200092 China Institute of Marine Organic Geochemistry Ocean University of China Qingdao 266100 China

Southern Hemisphere mid-latitude westerlies contribute to the ventilation of the deep Southern Ocean(SO),and drive changes in atmospheric carbon dioxide(CO2) and the global *** the westerlies control directly oceanic fronts,the movement of the subtropical front(STF) reflects the westerlies *** it is important to understand the relationships between STF movement and the weaterlies,ventilation of the deep SO,ice volume and atmospheric *** this end,we use two new high-resolution records from early Marine Isotope Stage(MIS) 20(～800 ka) of sea surface temperature(SST) based on U k' 37 paleo-thermometer and benthic oxygen isotope(δ 18OB) at Ocean Drilling Program(ODP) Site 1170B in the southern Tasman Sea(STS),to construct linkages between the marine records and atmospheric proxies from Antarctic *** the last 800 ka,the average SST(10.2℃) at Site 1170B is 1.8℃ lower than today(annual average 12℃).The highest average SST of 11.6℃ occurred during MIS 1,and the lowest average SST of 7.8℃ occurred during MIS *** warmest and coldest records of 14.7℃ and 6.2℃ occurred in the MIS 5 and MIS 2,*** the glacial-interglacial cycles of the last 800 ka,variability of reconstructed SST shows that the STF moved northward or southward more than 3° of latitude compared with its present *** the warmest stage MIS 5,the STF shifted to its southernmost location of ～49°*** contrast,in the coldest stage MIS 2,the STF moved to its northernmost location of ～43°*** response to orbital cycles,the westerlies movement led ice volume and atmospheric CO2 changes,but it was in phase with change in Antarctic atmospheric *** volume only preceded atmospheric CO2 only a little at the 23-ka precession band,lagged the atmospheric CO2 at the 100-ka eccentricity band,and was in phase with atmospheric CO2 at the 40-ka obliquity band.

关键词：海面温度塔斯曼海亚热带运动大气CO2浓度大气二氧化碳海洋钻探计划管理信息系统

Walsh Spectrum Properties of Rotation Symmetric Boolean Function

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Wuhan University Journal of Natural Sciences 2006年第6期11卷 1862-1864页

作者： WANG Yongjuan HAN wenbao li Shiqu Institute of Information Engineering Information Engineering University Zhengzhou 450002 Henan China

Rotation symmetric function was presented by Pieprzyk. The algebraic configuration of rotation symmetric（RotS） function is special. For a Rots n variables function f（x1, x2, …, xn） we have f（ρn^k （x1, x2, …xn））=f（x1, x2, …, xn） for k=0, 1, …, n-1. In this paper, useing probability method we find that when the parameters of RotS function is under circular translation of indices, its walsh spectrum is invariant. And we prove the result is both sufficient and necessary.

关键词： rotation symmetric function rotation shift Walsh spectra

Synthesis and Pharmacokinetic Property Improvement of Deuterated Plinabulin 9

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Journal of Ocean University of China 2017年第2期16卷 305-310页

作者： ZHAO Jianchun CHENG Hejuan SUN Tianwen WANG Shixiao DING Zhongpeng DOU Guifang MENG Zhiyun GUAN Huashi li wenbao Key Laboratory of Marine Drugs of Ministry of Education of China School of Medicine and PharmacyOcean University of ChinaQingdao 266003P.R.China Marine Biomedical Research Institute of Qingdao Qingdao 266073P.R.China Institute of Transfusion Medicine Academy of Military Medical ScienceBeijing 100850P.R.China

Plinabulin,a potent microtubule-targeting agent,is derived from marine natural diketopiperazine ‘phenylahistin'.To develop novel plinabulin analogue that could display better pharmacokinetic properties and less side effects,deuterated plinabulin 9 was synthesized and evaluated in vitro and in *** comparison with plinabulin,in vivo pharmacokinetic studies indicated that the deuterated derivative 9 could alter blood circulation behavior obviously,which was proved by increased area under the plasma concentration-time curve(AUC_(0–∞)),reduced clearance(CL),and prolonged total body mean residence time(MRT).The derivative 9 also has higher inhibition rates against Bx PC-3,Jurkat and A-431 tumor cell lines as compared with its prototype ***,the deuterated compound 9 might be developed as a potential agent for different cancer treatments.

关键词： plinabulin diketopiperazine antitumor deuteration pharmacokinetics

Effects of desert plant communities on soil enzyme activities and soil organic carbon in the proluvial fan in the eastern foothills of the Helan Mountain in Ningxia,China

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Journal of Arid Land 2024年第5期16卷 725-737页

作者： SHEN Aihong SHI Yun MI wenbao YUE Shaoli SHE Jie ZHANG Fenghong GUO Rui HE Hongyuan WU Tao li Hongxia ZHAO Na College of Forestry and Prataculture of Ningxia University Yinchuan 750021China School of Geography and Planning of Ningxia University Yinchuan 750021China Ningxia Hui Autonomous Region Agricultural Comprehensive Development Center Yinchuan 750002China Ningxia Helan Mountain National Nature Reserve Administration Yinchuan 750021China Yinchuan Yinxi Ecological Protection Forest Management Center Yinchuan 750002China

It is of great significance to study the effects of desert plants on soil enzyme activities and soil organic carbon(SOC)for maintaining the stability of the desert *** this study,we studied the responses of soil enzyme activities and SOC fractions(particulate organic carbon(POC)and mineral-associated organic carbon(MAOC))to five typical desert plant communities(Convolvulus tragacanthoides,Ephedra rhytidosperma,Stipa breviflora,Stipa tianschanica ***,and Salsola laricifolia communities)in the proluvial fan in the eastern foothills of the Helan Mountain in Ningxia Hui Autonomous Region,*** recorded the plant community information mainly including the plant coverage and herb and shrub species,and obtained the aboveground biomass and plant species diversity through sample surveys in late July *** samples were also collected at depths of 0–10 cm(topsoil)and 10–20 cm(subsoil)to determine the soil physicochemical properties and enzyme *** results showed that the plant coverage and aboveground biomass of *** community were significantly higher than those of ***,***,and *** *** communities(Pline phosphatase(ALP)andβ-1,4-glucosidas(βG)were significantly higher in *** and *** *** communities than in other plant communities(P<0.05).The topsoil had higher POC and MAOC contents than the ***,the content of POC in the topsoil was 18.17%–42.73%higher than that in the *** structural equation model(SEM)indicated that plant species diversity,soil pH,and soil water content(SWC)were the main factors influencing POC and *** soil pH inhibited the formation of POC and promoted the formation of ***,SWC stimulated POC production and hindered MAOC *** study aimed to gain insight into the effects of desert plant c

关键词： proluvial fan desert plant community soil enzyme activity particulate organic carbon mineral-associated organic carbon Helan Mountain

近2 Ma BP以来地球轨道参数周期上全球海平面变化机制

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地球科学（中国地质大学学报） 2016年第5期41卷 742-756页

作者：李文宝王汝建同济大学海洋地质国家重点实验室上海020092 内蒙古农业大学水资源保护与利用自治区重点实验室内蒙古呼和浩特010018

海平面的变化往往对区域生态环境、社会经济造成严重影响.通过对全球相对海平面变化(relative sea level,简称RSL)记录的再分析结果,合成了近2 Ma BP以来的全球RSL变化记录,分析了合成RSL记录对原始RSL记录数理特征的继承性,并基于频谱... 详细信息

海平面的变化往往对区域生态环境、社会经济造成严重影响.通过对全球相对海平面变化(relative sea level,简称RSL)记录的再分析结果,合成了近2 Ma BP以来的全球RSL变化记录,分析了合成RSL记录对原始RSL记录数理特征的继承性,并基于频谱、滤波等数理分析验证了合成RSL记录的合理性.在此基础上,讨论了合成RSL与大气CO_2浓度、中高纬度海域表层海水温度(sea surface temperature,简称SST)、全球大洋底栖氧同位素(δ^(18)O_B)等参数指标间的相关性,结果显示:(1)合成RSL不仅与原始RSL记录的变化趋势基本一致,继承了原始RSL记录对全球气候变化的响应特征,而且显示出合成RSL记录对地球轨道参数周期变化响应明显;(2)近2 Ma BP以来,在冰期-间冰期旋回中,合成RSL与δ^(18)O_B变化呈良好的负相关,相关系数r平均值可以达到约0.81,高于合成RSL与大气CO_2浓度及中高纬度海域SST变化的相关系数;(3)在地球轨道参数周期上,合成RSL与极地冰盖体积(δ^(18)O_B)的变化几乎同时,在偏心率周期上,合成RSL落后于SST和大气CO_2浓度变化;在斜率周期上,合成RSL落后于SST变化而领先于大气CO_2浓度变化.推测这些变化的诱导因素可能是在太阳辐射量改变的前提下,大气CO_2浓度及大洋SST变化对极地冰盖体积产生了差异影响,进而引起海平面发生变化.

关键词：海平面极地冰盖相关性 2 Ma BP 气候变化

内蒙古高原达里诺尔湖夏季水体稳定同位素变化特征

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湖泊科学 2019年第2期31卷 539-550页

作者：李文宝刘志娇杨旭李畅游内蒙古农业大学水资源保护与利用自治区重点实验室呼和浩特010018

基于内蒙古高原寒-旱区达里诺尔湖(简称"达里湖")相对集中的夏季大气降水、强烈的蒸发作用等典型区域气候环境特征,结合湖泊水体温度、盐度等理化指标变化,对夏季达里湖湖水、入湖河水、区域大气降水等样品中稳定氢、氧同位素(δD、δ^(... 详细信息

基于内蒙古高原寒-旱区达里诺尔湖(简称"达里湖")相对集中的夏季大气降水、强烈的蒸发作用等典型区域气候环境特征,结合湖泊水体温度、盐度等理化指标变化,对夏季达里湖湖水、入湖河水、区域大气降水等样品中稳定氢、氧同位素(δD、δ^(18)O)值变化进行了对比分析.结果显示:虽然整体上达里湖夏季水体并没有形成明显的物理性质"跃层"(如温跃层、盐跃层等),水体理化指标的空间分布相对稳定,但是夏季湖水中δD、δ^(18)O值却随着水深增加逐渐偏负:δD值由表层水体(0～1 m)到底层水体(7～9 m)偏负约1.40‰,δ^(18)O值由表层水体到底层水体偏负约0.27‰.达里湖夏季"大气水线"为δD=8.22δ^(18)O+6.82,显示大气降水中δD、δ^(18)O值受季风降水效应影响的同时受到区域蒸发作用影响.特别是7、8月大气降水同位素变化受降水效应的影响比6、9月更明显,而6、9月大气降水同位素变化受蒸发作用的影响比7、8月更明显.这也导致达里湖夏季上层水体受大气降水的稀释作用影响显著;伴随水深的增加,降水效应及蒸发作用的混合影响逐渐减弱,底层水体受区域地下水补给过程等因素的影响则可能更加明显,即达里湖夏季上层水体和底层水体中稳定同位素组成变化的影响因素存在差异.

关键词：氢同位素氧同位素水文过程夏季达里诺尔湖