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Photocatalytic direct oxygen-isotopic labelings of carbonyls in ketones and aldehydes with oxygen-isotopic waters

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Chinese Chemical Letters 2023年第11期34卷 131-136页

作者： Xianjin Zhu Yong Liu Lunyu ou Haijun yang Hua fu Key Laboratory of Bioorganic Phosphorus Chemistry and Chemical Biology(Ministry of Education) Department of ChemistryTsinghua UniversityBeijing 100084China

Oxygen-isotopic labelings play important roles in identifying and understanding chemical and biological *** C=O to C=^(18)O or C=^(17)O conversion in a single step leading to labeled compounds can alleviate synthetic burdens without the need for *** we describe a photocatalytic oxygenisotopic labeling protocol that can efficiently and selectively install ^(18)O and ^(17)O on carbonyls of ketones and aldehydes via oxygen isotope exchange with oxygen-isotopic waters(H_(2)^(18)O or H_(2)^(17)O)as the sources of oxygen isotopes,in which light and oxygen-enabled sodium alkanesulfinates catalyzed this *** strategy was extended to the in-situ formed ketones from the photocatalytic aerobic oxidation of alkyl arenes and secondary ***,reduction of the oxygen-isotopically labeled aldehydes with NaBH_(4) provided the corresponding oxygen-isotopically labeled primary *** believe that the oxygen-isotopically labeling method will be widely used in chemistry,biology and medicine fields.

关键词： Oxygen-isotopic labeling Photocatalysis Oxygen-isotopic waters Compounds containing carbonyls Alkanesulfinates

A Video Captioning Method by Semantic Topic-Guided Generation

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Computers, Materials & Continua 2024年第1期78卷 1071-1093页

作者： ou Ye Xinli Wei Zhenhua Yu Yan fu Ying yang College of Computer Science and Technology Xi’an University of Science and TechnologyXi’an710054China

In the video captioning methods based on an encoder-decoder,limited visual features are extracted by an encoder,and a natural sentence of the video content is generated using a ***,this kind ofmethod is dependent on a single video input source and few visual labels,and there is a problem with semantic alignment between video contents and generated natural sentences,which are not suitable for accurately comprehending and describing the video *** address this issue,this paper proposes a video captioning method by semantic topic-guided ***,a 3D convolutional neural network is utilized to extract the spatiotemporal features of videos during the ***,the semantic topics of video data are extracted using the visual labels retrieved from similar video *** the decoding,a decoder is constructed by combining a novel Enhance-TopK sampling algorithm with a Generative Pre-trained Transformer-2 deep neural network,which decreases the influence of“deviation”in the semantic mapping process between videos and texts by jointly decoding a baseline and semantic topics of video *** this process,the designed Enhance-TopK sampling algorithm can alleviate a long-tail problem by dynamically adjusting the probability distribution of the predicted ***,the experiments are conducted on two publicly used Microsoft Research Video Description andMicrosoft Research-Video to Text *** experimental results demonstrate that the proposed method outperforms several state-of-art ***,the performance indicators Bilingual Evaluation Understudy,Metric for Evaluation of Translation with Explicit Ordering,Recall Oriented Understudy for Gisting Evaluation-longest common subsequence,and Consensus-based Image Description Evaluation of the proposed method are improved by 1.2%,0.1%,0.3%,and 2.4% on the Microsoft Research Video Description dataset,and 0.1%,1.0%,0.1%,and 2.8% on the Microsoft Research-Video to Text dataset

关键词： Video captioning encoder-decoder semantic topic jointly decoding Enhance-TopK sampling

Design,synthesis and in vitro evaluation of mono(2,2,2-trifluoroethyl)esters,mono L-amino acid ester prodrugs of acyclic nucleoside phosphonates as anti-HBV agents

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Chinese Chemical Letters 2011年第12期22卷 1387-1390页

作者： Xiao Zhong fu Yu ou Jan Xin Yu She yang School of Pharmacy Guiyang Medical CollegeGuiyang 550004China Shanghai fudan-Yueda Bio-Tech Co. Ltd.Shanghai 201203China State Key Laboratory of Drug Research Shanghai Institute of Materia MedicaShanghai Institute for Biological Sciences Chinese Academy of ScienceShanghai 201203China

A series of novel mono（2,2,2-trifluoroethyl） esters,mono L-amino acid ester prodrugs of acyclic nucleoside phosphonates was synthesized and their in vitro anti-HBVactivity was evaluated in HepG 2 2.2.15 *** 1d exhibited more potent anti-HBV activity and lower cytotoxicity than those of adefovir dipivoxil and alamifovir（MCC-478） with EC_（50） and CC_（50） values of 0.01μmol/L and 8000μmol/L respectively.

关键词： Acyclic nucleoside phosphonates L-Amino acid Prodrug

A Coordination-Based Algorithm for Dedicated Destination Vehicle Routing in B2B E-Commerce

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Computer Systems Science & Engineering 2022年第3期40卷 895-911页

作者： Tsung-Yin ou Chen-yang Cheng Chun Hsiung Lai Hsin-Pin fu Department of Marketing and Distribution Management National Kaohsiung University of Science and TechnologyTaiwan Department of Industrial Engineering and Management Taipei University of TechnologyTaiwan Department of Enterprise Information and Industrial Engineering Tunghai UniversityTaiwan

This paper proposes a solution to the open vehicle routing problem with time windows(OVRPTW)considering third-party logistics(3PL).For the typical OVRPTW problem,most researchers consider time windows,capacity,routing limitations,vehicle destination,*** researchers who previously investigated this problem assumed the vehicle would not return to the depot,but did not consider its final ***,by considering 3PL in the B2B e-commerce,the vehicle is required back to the nearest 3PL location with available *** paper formulates the problem as a mixed integer linear programming(MILP)model with the objective of minimizing the total travel distance.A coordinate representation particle swarm optimization(CRPSO)algorithm is developed to obtain the best delivery sequencing and the capacity of each *** of the computational study show that the proposed method provides solution within a reasonable amount of ***,the result compared to PSO also indicates that the CRPSO is effective.

关键词： Third-party logistics open vehicle routing problem with time windows dedicated destination Notations

Luminescence property and magnetic resonance imaging of Gd_(2)O_(3):Tb^(3+) nanocrystals doped with Zn^(2+),Li^(+)

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Rare Metals 2021年第8期40卷 2049-2058页

作者： Rong fu Yan-Yan Hu Hui-Na Qiao Chun-Lin yang Hao Yin Mei-Gui ou College of Materials and Metallurgy University of GuizhouGuiyang550025China National Local Co-construction Engineering Laboratory for High Performance Metal Structure Material and Manufacture Technology Guiyang550025China College of Chemistry and Materials Engineering Guiyang UniversityGuiyang550003China Department of Neurosurgery Guizhou Provincial People’s HospitalGuiyang550002China

Gd_(2)O_(3):Tb^(3+) nanocrystal co-doped with Zn^(2+)and Li^(+) was prepared by the combination of polyol and solid-phase *** synthesized nanoparticles were characterized by X-ray diffraction(XRD),field emission scanning electron microscopy(FESEM),transmission electron microscopy(TEM),photoluminescence(PL)spectra and magnetic resonance imaging(MRI).The results revealed that both Gd_(2)O_(3):Tb^(3+)/Zn^(2+) and Gd_(2)O_(3):Tb^(3+)/Li^(+) had cubic unit structures with a spherical shape,and the fluorescence intensity of the nanoparticles reached a maximum at a doping concentration of0.050 mmol%for Zn^(2+) and 2 mol%for Li^(+),*** addition,the T_(1)/T_(2)(longitudinal/transverse relaxation time)-weighted MRI signals got enhanced due to the increased longitudinal relaxivity(r1)and transverse relaxivity(r2)after the doping by metal ***,the materials reported here can be used for fluorescence and MR bimodal imaging,as tracers and for fluorescence detections.

关键词： Gd_(2)O_(3):Tb^(3+) Zn^(2+)/Li^(+)doping Luminescent property Magnetic resonance imaging Nanomaterials

Superhigh selective capture of volatile organic compounds exploiting cigarette butts-derived engineering carbonaceous adsorbent

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Chinese Journal of Chemical Engineering 2022年第6期35卷 194-206页

作者： Wenjian Zhu Xuhua Shen Rui ou Manoj Murugesan Aihua Yuan Jianfeng Liu Xiaocai Hu Zhen yang Ming Shen fu yang School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China Marine Equipment and Technology Institute Jiangsu University of Science and TechnologyZhenjiang 212003China Shanghai Waigaoqiao Shipbuilding Co. LtdShanghai 200137China School of Chemistry and Chemical Engineering Yangzhou UniversityYangzhou 212003China Jiangsu Agricultural Hormone Engineering Technology Research Center Co.Ltd Changzhou 213022China

Herein,we develop cost-efficient superhigh-performance of engineering carbonaceous adsorbent from cigarette butts using combined wet-impregnated and re-dispersed method of KOH,which optimizes the implant approach of activator,breaking the restriction of selective capture of toluene using traditional activated *** Brunauer-Emmett-Teller(BET)surface area and pore volume of targeted adsorbent can attain 3088 m^(2)·g^(-1) and 1.61 cm^(3)·g^(-1),respectively,by optimizing the temperaturedependent synthetic factor effect of the *** adsorption capacity of resultant adsorbent for presenting volatile benzene and toluene shows a positive correlation with increasing carbonization temperature of carbon ***,we demonstrated the unsmoked and smoked butts derived adsorbents afford feeble difference in saturated adsorbed capacity of volatile organic compounds(VOCs).The highest adsorption capacity of sample CF-800 for benzene and toluene in CF group is as high as 1268.1 and 1181.6 mg·g^(-1) respectively,slightly higher than that of sample UF-800,but far outperforming reported other *** predicted adsorption selectivity of CF-800 and UF-800 for C_(7)H_(8)/H_(2)O(g)using the DIH(difference of isosteric heats)equation reach up to ca.3800 and 7500 respectively,indicating the weak adsorbability of water vapor on the developed adsorbent and greater superiority of the smoked butts derived adsorbents in selective capture of VOCs at low relative humidity in the competitive adsorption process for practical mixed VOCs.

关键词： Purification Activated carbon Benzene Toluene Adsorbents Selectivity

“Reinforced concrete”-like flexible transparent electrode for organic solar cells with high efficiency and mechanical robustness

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Science China Chemistry 2022年第6期65卷 1164-1172页

作者： yang Chen Juanyong Wan Guiying Xu Xiaoxiao Wu Xinqi Li Yunxiu Shen fu yang Xuemei ou Yaowen Li Yongfang Li Laboratory of Advanced Optoelectronic Materials Suzhou Key Laboratory of Novel Semiconductor-optoelectronics Materials and DevicesCollege of ChemistryChemical Engineering and Materials ScienceSoochow UniversitySuzhou215123China State and Local Joint Engineering Laboratory for Novel functional Polymeric Materials Jiangsu Key Laboratory of Advanced Functional Polymer Dsign and ApplicationSoochow UniversitySuzhou215123China Beijing National Laboratory for Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeijing100190China

Flexible transparent electrodes(FTEs) with robust mechanical stability are crucial for the industrial application of flexible organic solar cells(OSCs). However, their production remains challenging owing to the difficulty in balancing the conductivity,transmittance, and adhesion of FTEs to substrates. Herein, we present the so-called “reinforced concrete” strategy which finetunes the structure of silver nanowires(Ag NWs)-based FTEs with polydopamine(PDA) possessing good adhesion properties and moderate reducibility. The PDA reduces Ag+to form silver nanoparticles(Ag NPs) which grow like “rivets” at the Ag NW junction sites;PDA stabilizes the Ag NW skeleton and improves the adhesion between the Ag NWs and polyethylene terephthalate(PET) substrate and interface layer. The obtained Ag NW:PDA:Ag NP FTE exhibits excellent optoelectronic properties and high mechanical stability. The resulting flexible OSCs exhibit 17.07% efficiency, high flexibility during 10,000 bending test cycles, and robust peeling stability. In addition, this “reinforced concrete”-like FTE provides great advantages for the production of large-area flexible OSCs, thereby paving a new way toward their commercial application.

关键词： flexible organic solar cells flexible transparent electrodes silver nanowires polydopamine mechanical stability

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Corrosion risk analysis of tube-and-shell heat exchangers and design of outlet temperature control system

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Petroleum Science 2021年第4期18卷 1219-1229页

作者： Hao-Zhe Jin Yong Gu Guo-fu ou The Institute of Flow-Induced Corrosion Zhejiang Sci-tech UniversityHangzhou310000ZhejiangChina Institute of Flow Induced Corrosion and Intelligent Prevention and Control Changzhou UniversityChangzhou213000JiangsuChina

This study deals with the high-risk shell-and-tube heat exchangers in the effluent system of hydrogenation reaction of the petrochemical *** process of hydroprocessing reactor effluent system is simulated in Aspen Plus to study the distribution of corrosive medium in the three phases of oil,gas and *** least-squares method is utilized to calculate the ammonium salt crystallization ***,the heat exchanger with risk of ammonium salt crystal corrosion is *** mathematical modeling of the heat exchanger is established to determine the transfer function.A temperature control system with proportional integral derivative(PID)control of the heat exchanger outlet is designed,and fuzzy logic is used to implement self-tuning of PID *** MATLAB simulation,the results show the control system can achieve rapid control of the heat exchanger outlet temperature.

关键词： Shell-and-tube heat exchanger Corrosion risk Dynamic model fuzzy logic control PID control

Relation Between Cellular Senescence and Liver Diseases

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Chinese Medical Sciences Journal 2016年第2期31卷 121-126页

作者： Guo-wen Li Xue-feng yang Nian fu Yan ou-yang Kai Qing Department of Gastroenterology the Affiliated Nanhua Hospital of University of South China

Cellular senescence refers to a process that cellular proliferation and differentiation modulated by the multiple stimulating factors gradually decline. Aging cells present the irreversible stop of proliferation and differentiation and change in secretory function because the cell cycle of aging cells is steadily blocked at some point. It has have been shown that cellular senescence plays an important role in the occurrence and development of liver diseases. In this paper, we review the advances in relations between cellular senescence and liver diseases.

关键词： cellular senescence mechanism liver diseases liver fibrosis liver cancer