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Impacts of Water-Sediment Regulation Scheme on Chromophoric Dissolved Organic Matter in the Lower Yellow River

Journal of Ocean University of China 2024年第2期23卷 455-466页

作者： liU xiao JIANG Xueyan liU Qian SUI Juanjuan ZOU li Key Laboratory of Marine Chemistry Theory and Technology of Ministry of Education Ocean University of ChinaQingdao 266100China College of Chemistry and Chemical Engineering Ocean University of ChinaQingdao 266100China School of Earth Sciences University of BristolBristolBS81RJUK North China Sea Environmental Monitoring Center State Oceanic AdministrationQingdao 266033China Key Laboratory of Ecological Prewarning Protection and Restoration of Bohai SeaMinistry of Natural ResourcesQingdao 266033China Key Laboratory of Marine Environment and Ecology of Ministry of Education Ocean University of ChinaQingdao 266100China College of Environmental Science and Engineering Ocean University of ChinaQingdao 266100China

As a river with more than 3000 reservoirs in its watershed,the Yellow River has been affected by dams not only on the sediment load,but also on the water ***-sediment regulation scheme(WSRS),which has been carried out annually in the Yellow River since 2002,is a typical human activity affecting river water *** dissolved organic matter(CDOM)in river is susceptible to changes in ecological and environmental conditions as well as human ***,we report variations in dissolved organic carbon concentrations,compositions and sources of CDOM in time series samples in the lower Yellow River during *** addition,a parallel factor fluorescence analysis(PARAFAC)method is applied to identify different fluorescent components in water samples during WRSR,showing four major components including tryptophan-like component(C1),microbial humic-like component(C2),terrestrial humic-like component(C3)and tyrosine-like component(C4).In general,C1 increased after water regulation,while C2 and C3 increased after sediment regulation,indicating that the water and sediment released by the dam have different effects on CDOM *** the impacts of the dam,source of CDOM in the lower Yellow River is mainly autochthonous related to microbial activities,and is regulated by the terrestrial input during WSRS *** resuspension inhibits microbial activities and reduces the production of autochthonous ***,human activities especially WSRS,as exemplified here,significantly alter the quality and quantity of CDOM in the lower Yellow River,affecting CDOM dynamics and biogeochemical processes in the estuarine environment.

关键词： chromophoric dissolved organic matter(CDOM) water-sediment regulation scheme(WSRS) Yellow River optical properties

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Difluoroalkylation/Lactonization of Alkenes with BrCF_(2)CO_(2)K via Photoredox Catalysis:Access toα,α-Difluoro-γ-lactones

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Chinese Journal of Chemistry 2023年第21期41卷 2819-2824页

作者： Min Zhang Qiang li Jin-Hong lin Ji-Chang xiao Key Laboratory of Organofluorine Chemistry Shanghai Institute of Organic ChemistryUniversity of Chinese Academy of SciencesChinese Academy of Sciences345 Lingling RoadShanghai200032 China Department of Chemistry Innovative Drug Research CenterShanghai UniversityShanghai200444 China

Due to its unique electronic properties,the difluoromethylene group(CF2)has served as a valuable unity in the design of biologically active ***γ-lactones display a broad range of biological properties,α,α-difluoro-γ-lactones may exhibit unexpected biological activities,and thus their synthesis has received increasing *** synthetic methods suffer from tedious multi-step processes,and very few effective methods have been reported ***,we describe the difunctionalization of alkenes with BrCF_(2)CO_(2)K under photoredox catalysis with the use of a boron-Lewis acid for the access toα,α-difluoro-γ-*** this transformation,the alkene substrates and the used reagents,including BrCF_(2)CO_(2)K and the boron-Lewis acid,PhB(OH)2 or BF3·THF,are cheap and widely *** efficiency and atom economy may make this protocol attractive.

关键词： Photoredox Catalysis Fluorine Lactones Alkenes

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Entropy-Based Global and Local Weight Adaptive Image Segmentation Models

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Tsinghua Science and Technology 2020年第1期25卷 149-160页

作者： Gang li yi Zhao ling Zhang Xingwei Wang Yueqin Zhang Fayun Guo Taiyuan University of Technology Taiyuan 030024China College of Computer Science and Engineering Northeastern UniversityShengyang 110819China Shanxi Tizones Technology Co.Ltd. Taiyuan 030082China Fayun Guo is with Shanxi Taisen Technology Co.Ltd. Taiyuan 030082China

This paper proposes a parameter adaptive hybrid model for image segmentation. The hybrid model combines the global and local information in an image, and provides an automated solution for adjusting the selection of the two weight parameters. Firstly, it combines an improved local model with the global Chan-Vese(CV) model, while the image’s local entropy is used to establish the index for measuring the image’s gray-level information. Parameter adjustment is then performed by the real-time acquisition of the ratio of the different functional energy in a self-adapting model responsive to gray-scale distribution in the image segmentation *** with the traditional linear adjustment model, which is based on trial-and-error, this paper presents a more quantitative and intelligent method for achieving the dynamic nonlinear adjustment of global and local *** show that the proposed model achieves fast and accurate segmentation for different types of noisy and non-uniform grayscale images and noise images. Moreover, the method demonstrates high stability and is insensitive to the position of the initial contour.

关键词： image local entropy parameter adaption image segmentation active contour

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Thrombus straddling a patent foramen ovale and pulmonary embolism:A case report

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World Journal of Clinical Cases 2020年第20期8卷 4902-4907页

作者： yi-Xiong Huang Yu Chen yi Cao yi-Gang Qiu Jian-Yong Zheng Tian-Chang li Department of Cardiology Sixth Medical Center of PLA General HospitalBeijing 100048China

BACKGROUND Venous thromboembolism is a common vascular syndrome presenting as deep vein thrombosis and/or pulmonary *** has the possibility of migrating into the left circulation via patent foramen ovale in certain extreme *** straddling a patent foramen ovale is a direct evidence of this ***,the confirmed cases of thrombus in transit are still *** SUMMARY A 32-year-old man suffered from recurrent syncope and intermittent dyspnea for 1 *** echocardiography confirmed a thrombus straddling the patent foramen ovale,and thrombi were also found in the bilateral pulmonary artery by computed *** man underwent inferior vena cava filter placement and thrombolysis with *** showed the absence of thrombi in both the right atrium and left atrium 2 d after *** man was discharged to home on warfarin without any complications 2 wk *** Scrutinizing intracardiac thrombi provides measurable value in pulmonary embolism as closure of patent foramen ovale may be considered in certain *** intervention plays a critical role in thrombus straddling a patent foramen ovale.A sedentary lifestyle may predispose young adults to thromboembolism,even if there are no other risk factors.

关键词： Thrombus Patent foramen ovale Pulmonary embolism Case report

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Phase Transition Temperature Controllable Poly(acrylamide-co-acrylic acid) Nanocomposite Physical Hydrogels with High Strength

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Chinese Journal of Polymer Science 2016年第10期34卷 1261-1269页

作者： li-qin zhang li-wen chen ming zhong fu-kuan shi xiao-ying liu 谢续明 Laboratory of Advanced Materials (MOE) Department of Chemical Engineering Tsinghua University Beijing 100084 China

Poly（acrylamide-co-acrylic acid） nanocomposite physical （P（AAm-co-AAc）NCP） hydrogels have been prepared through the in situ free radical solution polymerization based on a ＂single network, dual cross-linkings＂ strategy. The P（AAm-co-AAc） NCP hydrogels are composed of nanobrushes of P（AAm-co-AAc） chains grafted on the surface of vinyl- hybrid silica nanoparticles （VSNPs）. In the hydrogel system, the VSNPs act as the ＂analogous chemical cross-linking points＂ once the hydrogen bonds formed between the P（AAm-co-AAc） chains of the nanobrushes, thus leading to the fabrication of high-strength P（AAm-co-AAc） NCP hydrogels. Compared with conventional thermosensitive P（AAm-co-AAc） hydrogels, the P（AAm-co-AAc） NCP hydrogels have a broader range of phase transition temperature, which can be adjusted by altering the monomer ratio, the VSNPs concentration, the addition of urea and N,N-dimethylacrylamide （DMAAm）. At the same time, the mechanical properties of the P（AAm-co-AAc） NCP hydrogels have been improved significantly by the introduction of VSNPs. Furthermore, both the phase transition and the tensile strength of the P（AAm-co-AAc） NCP hydrogels are largely influenced when Fe3＋ ions are introduced as the ionic crosslinkers into the hydrogel networks.

关键词： Poly(acrylamide-co-acrylic acid) Nanocomposite physical hydrogels Phase transition High strength.

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Controlled-Release Oxycodone Alone or Combined with Gabapentin for Management of Malignant Neuropathic Pain

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Chinese Journal of Cancer Research 2010年第1期22卷 80-86页

作者： xiao-mei li Duan-qi liu Hang-yu Wu Chun Yang li Yang Department of Medical Oncology Department of Anatomy Capital Medical University Beijing 100069 China Departement of Medical Training the Beijing Military General Hospital of PLA Beijing 100700 China

Objective： To evaluate the analgesic efficacy of controlled-release （CR） oxycodone and gabapentin in malignant neuropathic pain （NP）. Methods： Patients with malignant NP were enrolled and baseline pain intensity （PI） was recorded. They initially took one week CR oxycodone and were allocated to two different groups at day 8 by reevaluated PI. Patients with mild pain went to CR oxycodone mono-therapy group （OO group） and took another two weeks CR oxycodone. Others went to （CR oxycodone combined gabapentin group （OG group） and received additional gabapentin. Daily doses and side effects were recorded. Results： Fifty-eight （92.06%） of the 63 enrolled patients completed the initial week＇s therapy. Twenty-two （37.93%） went to OO group and PI significantly reduced at day 15 （2.00 vs. 2.62, P=0.004）, but not improved at day 22 （1.90 vs. 2.00, P=0.54）. Thirty-six （62.07%） patients went to OG group and PI was significantly reduced at day 15 （4,47 vs. 2.94, P〈0.001）, but not improved at day 22 （2.94 vs. 2.75, P=0.136）. Mean daily dose （MDD） of CR oxycodone at day 8 was 62.64 mg. It was significantly increased at days 15 and 22 （71.43 mg vs. 62.64 rag, P=0.021; 81.90 mg vs. 71.43 mg, P=0.004） in OO group. MDD of gabapentin was significantly increased at day 22 compared to day 15 （862.50 mg vs. 993.75 mg, P〈0.001）. Constipation was occurred in 13.64% of the patients in OO group and 14.26 % in OG group. Conclusion： Malignant NP may be well controlled by oxycodone mono-therapy. Early combination with gabapentin is sensible when pain is not satisfactory relieved by oxycodone alone. The side effects of them are manageable.

关键词： CR oxyeodone Gabapentin Malignant neuropathic pain Analgesic efficacy

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Hydrocarbon generation from lacustrine shales with retained oil during thermal maturation

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Petroleum Science 2020年第6期17卷 1478-1490页

作者： Xin-He Shao Xiong-Qi Pang Mao-Wen li Zhi-Ming li yi Zhao State Key Laboratory of Petroleum Resources and Prospecting China University of PetroleumBeijing 102249China College of Geosciences China University of PetroleumBeijing 102249China State Key Laboratory of Shale Oil and Shale Gas Resources and Eff ective Development SINOPEC Petroleum Exploration and Production Research InstituteBeijing 100083China SINOPEC Key Laboratory of Petroleum Accumulation Mechanisms Wuxi Institute of Petroleum GeologyWuxi 214126JiangsuChina

Thermal maturation in the shale oil/gas system is inherently complex due to the competitive interplays between hydrocarbon generation and retention *** study hydrocarbon generation characteristics from shales within different stages of thermal maturation under the influence of retained oil,we performed Micro-Scale Sealed Vessels(MSSV)pyrolysis on a set of artificially matured lacustrine shale s amples from the Shahejie Formation in the Dongpu Depression in Bohai B ay Basin,*** results show that hydrocarbon yields of shale samples with or without retained oil at various thermal maturities follow different evolution *** components(C15+)in samples crack at high temperatures and generally follow a sequence,where they first transform into C6-14 then to C2-5 and *** accounts for most of the gaseous products at high temperatures in all samples,with different *** cracking of C2-5 is the main methane-generating process in samples with retained oil,whereas the source of methane in samples without retained oil is *** the studied shales,retained oils at early-mature stage retard the transformation of liquid to gaseous hydrocarbon and prompt the cracking of C2-5 to C1 to some *** reaction related to gypsum in the studied samples is the primary reason that can explain the loss of hydrocarbon yields,especially at high *** addition,transformation of volatile hydrocarbons to gas and coke also accounts for the loss of generated hydrocarbon,as a secondary factor.

关键词： MSSV pyrolysis Hydrocarbon generation Lacustrine shales Thermal maturation Retained oil

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Visible light responsive spiropyran derivatives based on dynamic coordination bonds

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Chinese Chemical Letters 2023年第2期34卷 506-510页

作者： Xiong xiao Wei Zheng Yue Zhao Cheng-Hui li State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing National Laboratory of MicrostructuresCollaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210023China

Spiropyrans(SPs) are a well-known class of photochromic compounds and have found widespread application due to their unique properties. However, for many conventional SPs, high energy ultraviolet(UV)light is commonly essential to drive photoisomerization, leading to poor fatigue resistance. Moreover, the practical application of spiropyrans is hindered by their fast fading speed due to the instability of closed forms(SP) or open forms(MC). Herein, we disclose a novel strategy to address these challenges through introducing both electron-donating substituents to stabilize the SP and dynamic coordination bonds to stabilize the MC. The resulting new spiropyrans complexes exhibit negative photochromic properties, with fast visible light response, good stability of both SP and MC, and significantly improved fatigue resistance.

关键词： Negativephotochromic Spiropyran Visiblelightresponsive Dynamic coordination bonds Design guidelines

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Evaluation of Erythrocyte Iron Incorporation in Beijing Prepubertal Children Using a Single Stable Isotope Tracer Method

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Biomedical and Environmental Sciences 2020年第6期33卷 414-420页

作者： ZHANG Yu li Ya Jie REN Tong Xiang liU xiao Bing YANG li Chen PAO Jian Hua WANG Jurr YANG xiao Guang Key Laboratory of Trace Element Nutrition MOHChinese Center for Disease Control and PreventionBeijing 100050China Department of Preventive Medicine Changzhi Medical CollegeChangzhi 046000ShanxiChina National Institute of Metrology Beijing 100029China

Objective To analyze the rate of erythrocyte iron incorporation and provided guidance for the iron nutrition for prepubertal *** Fifty-seven prepubertal children of Beijing were involved in this study and each subject was orally administered 3 mg of 57 Fe twice daily to obtain a total of 30 mg 57 Fe after a 5-d period. The stable isotope ratios in RBCs were determined in 14 th day, 28 th day, 60 th day, and 90 th day. The erythrocyte incorporation rate in children was calculated using the stable isotope ratios, blood volume and body iron *** The percentage of erythrocyte 57 Fe incorporation increased starting 14 th day, reached a peak at 60 d(boys: 19.67% ± 0.56%, girls: 21.33% ± 0.59%) and then decreased. The erythrocyte incorporation rates of 57 Fe obtained for girls in 60 th day was significantly higher than those obtained for boys(P < 0.0001).Conclusions The oral administration of 57 Fe to children can be used to obtain erythrocyte iron incorporation within 90 d. Prepubertal girls should begin to increase the intake of iron and further studies should pay more attention to the iron status in prepubertal children.

关键词： Stable isotope tracer technique Iron Erythrocyte incorporation rate Beijing prepubertal children MC-ICP-MS

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Variation of electron density in spectral broadening process in solid thin plates at 400 nm

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Chinese Physics B 2021年第10期30卷 323-327页

作者： Si-Yuan Xu yi-Tan Gao xiao-Xian Zhu Kun Zhao Jiang-Feng Zhu Zhi-yi Wei School of Physics and Optoelectronic Engineering Xidian UniversityXi’an 710071China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China University of Chinese Academy of Sciences Beijing 100049China Songshan Lake Material Laboratory Dongguan 523808China

The generation of continuous spectrum centered at 400 nm from solid thin plates is demonstrated in this work.A continuum covering 365 nm to 445 nm is obtained when 125-µJ frequency-doubled Ti:sapphire laser pulses are applied to six thin fused silica plates at 1-kHz repetition *** generalized nonlinear Schrodinger equation simplified for forward propagation is solved numerically,the spectral broadening with the experimental parameters is simulated,and good agreement between simulated result and experimental measurement is *** variation of electron density in the thin plate and the advantage of a low electron density in the spectral broadening process are discussed.

关键词： nonlinear spectral broadening time-dependent nonlinear Schrodinger equation self-phase modu-lation electron density

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