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5S-Heudelotinone alleviates experimental colitis by shaping the immune system and enhancing the intestinal barrier in a gut microbiota-dependent manner

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Acta Pharmaceutica Sinica B 2024年第5期14卷 2153-2176页

作者： Qing Meng Jianshuang Guo Ke Lv Yang liu Jin Zhang Mingyue Li Xirui Cheng Shenghua Chen Xiaoguang Huo quan Zhang Yue Chen jing Li State Key Laboratory of Medicinal Chemical Biology College of PharmacyNankai UniversityTianjin 300353China College of Chemistry and Frontiers Science Center for New Organic Matter Haihe Laboratory of Sustainable Chemical TransformationsNankai UniversityTianjin 300071China Accendatech Company Ltd.Tianjin 300193China

Aberrant changes in the gut microbiota are implicated in many diseases,including inflammatory bowel disease(IBD).Gut microbes produce diverse metabolites that can shape the immune system and impact the intestinal barrier integrity,indicating that microbe-mediated modulation may be a promising strategy for preventing and treating *** fecal microbiota transplantation and probiotic supplementation are well-established IBD therapies,novel chemical agents that are safe and exert strong effects on the gut microbiota are urgently ***,we report the total synthesis of heudelotinone and the discovery of 5S-heudelotinone(an enantiomer)as a potent agent against experimental colitis that acts by modulating the gut microbiota.5S-Heudelotinone alters the diversity and composition of the gut microbiota and increases the concentration of short-chain fatty acids(SCFAs);thus,it regulates the intestinal immune system by reducing proinflammatory immune cell numbers,and maintains intestinal mucosal integrity by modulating tight junctions(TJs).Moreover,5S-heudelotinone(2)ameliorates colitis-associated colorectal cancer(CAC)in an azoxymethane(AOM)/dextran sulfate sodium(DSS)-induced in situ carcinoma ***,these findings reveal the potential of a novel natural product,namely,5S-heudelotinone,to control intestinal inflammation and highlight that this product is a safe and effective candidate for the treatment of IBD and CAC.

关键词： 5S-heudelotinone Total synthesis Inflammatory bowel disease Gut microbiota Short-chain fatty acids Immune system Intestinal barrier Drug discovery

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On electro-acoustic characteristics of a marine broadband sparker for seismic exploration

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Journal of Oceanology and Limnology 2024年第3期42卷 760-771页

作者： jing LI Kai liu Liancheng ZHANG Chenguang liu Yanliang PEI Baohua liu Key Laboratory of Marine Geology and Metallogency First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory of Marine Geology Laoshan LaboratoryQingdao 266237China Key Laboratory of Fluid Transmission Technology of Zhejiang Province Zhejiang Sci-Tech UniversityHangzhou 310018China Key Laboratory of Submarine Acoustic Investigation and Application of Qingdao(Preparatory) Qingdao 266061China Key Laboratory of Deep Sea Mineral Resources Development Shandong(Preparatory)Qingdao 266061China

The construction of major marine infrastructure projects and the exploration and development of deep-sea mineral resources require fine imaging of seabed strata and *** highresolution marine seismic exploration based on a high broadband sparker source is an important approach to reveal seabed stratum and reservoir structure,and identify *** optimize the performance of sparker seismic source,we investigated the electro-acoustic characteristics of spark discharge under conditions of different charging voltages and electrode *** show that the sound source level increased with the increase of the charging voltage,whereas the main frequency decreased when the charging voltage *** addition,it was found that the charging capacitance had more obvious influence on the main frequency than the sound source level *** the load energy decreased with increasing electrode number,the sound source level still increased but the main frequency ***,the primary to bubble(P/B)ratio increased with the increase of the electrode *** gain a deeper insight into the electro-acoustic characteristics,we investigate the relationship between sound source level and power peak,from which a good correlation was observed.A more practical statistical analysis on the rise rate of current was processed,and a perfect logarithmic function was ***,we found that the main frequency was most possibly subjected to the electrical energy,especially the charging energy per *** results indicate that the charging energy per electrode less than 10 J could increase the main frequency to above 300 *** last,the main frequency could be reduced to 20 Hz when the charging energy of a single-electrode discharge was enhanced to over 4 *** study shall be helpful in developing a sparker seismic source and improving the performance for marine engineering exploration and geohazard assessment.

关键词： high-resolution marine seismic exploration sparker seismic source sound source level main frequency electro-acoustic characteristics

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Study of deep transportation and plugging performance of deformable gel particles in porous media

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Petroleum Science 2024年第2期21卷 962-973页

作者： Wen-jing Zhao jing Wang Zhong-Yang Qi Hui-Qing liu National Key Laboratory of Petroleum Resources and Engineering China University of PetroleumBeijing102249China MOE Key Laboratory of Petroleum Engineering China University of PetroleumBeijing102249China

Deformable gel particles(DGPs) possess the capability of deep profile control and flooding. However, the deep migration behavior and plugging mechanism along their path remain unclear. Breakage, an inevitable phenomenon during particle migration, significantly impacts the deep plugging effect. Due to the complexity of the process, few studies have been conducted on this subject. In this paper, we conducted DGP flow experiments using a physical model of a multi-point sandpack under various injection rates and particle sizes. Particle size and concentration tests were performed at each measurement point to investigate the transportation behavior of particles in the deep part of the reservoir. The residual resistance coefficient and concentration changes along the porous media were combined to analyze the plugging performance of DGPs. Furthermore, the particle breakage along their path was revealed by analyzing the changes in particle size along the way. A mathematical model of breakage and concentration changes along the path was established. The results showed that the passage after breakage is a significant migration behavior of particles in porous media. The particles were reduced to less than half of their initial size at the front of the porous media. Breakage is an essential reason for the continuous decreases in particle concentration, size, and residual resistance coefficient. However, the particles can remain in porous media after breakage and play a significant role in deep plugging. Higher injection rates or larger particle sizes resulted in faster breakage along the injection direction, higher degrees of breakage, and faster decreases in residual resistance coefficient along the path. These conditions also led to a weaker deep plugging ability. Smaller particles were more evenly retained along the path, but more particles flowed out of the porous media, resulting in a poor deep plugging effect. The particle size is a function of particle size before inject

关键词： Physical simulation Deformable gel particle Breakage Particle size Residual resistance coefficient

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Molecular investigation into the transformation of recalcitrant dissolved organic sulfur in refinery sour water during stripping process

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Petroleum Science 2024年第3期21卷 2112-2119页

作者： Yu-Guo Li Chen He Chun-Mao Chen Fan liu quan Shi State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China State Key Laboratory of Coal Mining and Clean Utilization Beijing 100013China PetroChina Ningxia Petrochemical Company Yinchuan 750021NingxiaChina

Refinery sour water primarily originates from the tops of towers in various units and coker condensate,and cannot be discharged directly to a wastewater treatment plant due to high levels of chemical oxygen demand(COD)and organic sulfur *** after the recovery of H_(2)S from the sour water by the stripping process,the effluent still contains a high concentration of dissolved organic sulfur(DOS),which can have a huge bad *** chemical composition of dissolved organic matter(DOM)in refinery wastewater has been extensively studied,the investigation of recalcitrant DOS from sour waters remains *** the present study,chemical composition of sour water DOMs(especially DOS)was investigated using fluorescence spectroscopy(excitation-emission matrix,EEM)and mass spectrometry,including gas chromatography-mass spectrometry(GC-MS)and high-resolution Orbitrap *** GC-MS and EEM results showed that volatile and low-aromaticity compounds were effectively removed during the stripping process,while compounds with high hydrophilicity and humification degree were found to be more *** Orbitrap MS results showed that weak-polar oxygenated sulfur compounds were easier to be removed than oxygenated ***,the effluent still contained significant amounts of sulfur-containing compounds with multiple sulfur atoms,particularly in the form of highly unsaturated and aromatic *** Orbitrap MS/MS results of CHOS-containing compounds from the effluent indicate that the sulfur atoms may exist as sulfonates,disulfide bonds,*** the composition and structure of sour water DOS is crucial for the development of effective treatment processes that can target polysulfide compounds and minimize their impact on the environment.

关键词： Molecular transformation Dissolved organic sulfur Stripping process Refinery sourwater Orbitrap MS

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资源约束下的时间-费用交换问题研究

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系统工程理论与实践 2002年第9期22卷 42-46页

作者：刘伟刘景泉清华大学核能技术设计研究院北京100084

传统的活动网络时间 -费用交换问题着重研究如何通过增加费用压缩活动工期以实现项目费用最小 ,而没有考虑资源的约束 .考虑资源可用量限制情况下 ,建立了资源约束下的时间 -费用交换问题模型 .采用特殊编码方式为该模型设计了启发式遗... 详细信息

传统的活动网络时间 -费用交换问题着重研究如何通过增加费用压缩活动工期以实现项目费用最小 ,而没有考虑资源的约束 .考虑资源可用量限制情况下 ,建立了资源约束下的时间 -费用交换问题模型 .采用特殊编码方式为该模型设计了启发式遗传算法并编写了 VC++5 .0程序 ,用数值实例说明了该模型的合理性和程序的有效性 .该模型对项目业主和承包商之间的合同谈判决策具有借鉴意义 .

关键词：资源约束时间-费用交换问题遗传算法 TCTP问题

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Sliced Average Variance Estimation for Tensor Data

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 630-655页

作者： Chuan-quan LI Pei-wen XIAO Chao YING Xiao-hui liu School of Statistics Jiangxi University of Finance and EconomicsNanchang 330013China Key Laboratory of Data Science in Finance and Economics Jiangxi University of Finance and EconomicsNanchang 330013China Biostatistics and Medical Informatics University of Wisconsin MadisonMadison 53726USA

Tensor data have been widely used in many fields,e.g.,modern biomedical imaging,chemometrics,and economics,but often suffer from some common issues as in high dimensional *** to find their low-dimensional latent structure has been of great interest for *** this end,we develop two efficient tensor sufficient dimension reduction methods based on the sliced average variance estimation(SAVE)to estimate the corresponding dimension reduction *** first one,entitled tensor sliced average variance estimation(TSAVE),works well when the response is discrete or takes finite values,but is not■consistent for continuous response;the second one,named bias-correction tensor sliced average variance estimation(CTSAVE),is a de-biased version of the TSAVE *** asymptotic properties of both methods are derived under mild *** and real data examples are also provided to show the superiority of the efficiency of the developed methods.

关键词： tensor data sliced average variance estimation sufficient dimension reduction central subspace

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Enhanced electrochemical oxidation of perfluorooctanoic acid on Ti/SnO_(2)-Sb electrode by surface morphology regulation

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Chinese Chemical Letters 2024年第3期35卷 140-143页

作者： Kaiqiang Hou Genwang Zhu Yujie Feng Yanming liu Xie quan Key Laboratory of Industrial Ecology and Environmental Engineering(Ministry of Education China)School of Environmental Science and TechnologyDalian University of TechnologyDalian 116024China State Key Laboratory of Urban Water Resource and Environment School of EnvironmentHarbin Institute of TechnologyHarbin 150090China

Electrochemical oxidation is an effective method to degrade persistent organic ***,due to the limited catalytic activity of traditional thin film electrodes,the anodic oxidation process is slow and usually requires high energy ***,Ti/SnO_(2)-Sb electrode with regulated surface structure was reported to enhance the performance for electrochemical oxidation of persistent organic *** electrode deposited with SnO_(2)-Sb nanoneedles(Ti/N-SnO_(2)-Sb)showed higher oxidation *** kinetic constant for perfluorooctanoic acid(PFOA)oxidation was 2.0 h^(-1)and the total organic carbon removal rate was 81.7%(4 h)at a relatively low current density of 6 mA/cm^*** with Ti/SnO_(2)-Sb thin film and nanoparticles,Ti/N-SnO_(2)-Sb significantly improved the electrochemical active area and·OH yield,and simultaneously reduced the electron transfer resistance,which enabled it to oxidize PFOA more rapidly even at a lower *** work provides a new strategy for promoting the electrochemical oxidation performance.

关键词： Electrochemical oxidation Nanoneedle SnO_(2)-Sb Perfluoroalkyl compounds Electrochemical degradation Persistent organic pollutants

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Thermal fatigue and wear of compacted graphite iron brake discs with various thermomechanical properties

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China Foundry 2024年第3期21卷 248-256页

作者： Gui-quan Wang Zhuo Xu Zhong-li liu Xiang Chen Yan-xiang Li School of Nuclear Equipment and Nuclear Engineering Yantai UniversityYantai 264005ShandongChina School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Ministry of EducationBeijing 100084China

The increase in payload capacity of trucks has heightened the demand for cost-effective yet high performance brake *** this work,the thermal fatigue and wear of compacted graphite iron brake discs were investigated,aiming to provide an experimental foundation for achieving a balance between their thermal and mechanical *** graphite iron brake discs with different tensile strengths,macrohardnesses,specific heat capacities and thermal diffusion coefficients were produced by changing the proportion and strength of *** peak temperature,pressure load and friction coefficient of compacted graphite iron brake discs were analyzed through inertia friction *** morphology of thermal cracks and 3D profiles of the worn surfaces were also *** is found that the thermal fatigue of compacted graphite iron discs is determined by their thermal properties.A compacted graphite iron with the highest specific heat capacity and thermal diffusion coefficient exhibits optimal thermal fatigue *** of the matrix at low temperatures significantly weakens the function of alloy strengthening in hindering the propagation of thermal *** the reduced hardness,increasing the ferrite proportion can mitigate wear loss resulting from low disc temperatures and the absence of abrasive wear.

关键词： compacted graphite iron brake disc thermomechanical properties thermal fatigue wear

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Ru(Ⅱ)-Catalyzed Selective C-H Alkynylation of Isoquinolones,Quinazolones and Phthalazinones with Bromoalkynes

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Chinese Journal of Chemistry 2024年第15期42卷 1686-1690页

作者： quan-Jian Luo Han-Chi Wang jing Zhang Jin-Heng Li Bo Sun State Key Laboratory Base of Eco-Chemical Engineering College of Chemical EngineeringQingdao University of Science and TechnologyQingdaoShandong 266042China State Key Laboratory of Applied Organic Chemistry Lanzhou UniversityLanzhouGansu 730000China School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan 453007China

A new,selective Ru(Ⅱ)-catalyzed alkynylation reaction of isoquinolones,quinazolones and phthalazinones with readily available bromoalkynes has been *** reaction enables the selective construction of a new C(sp^(2))-C(sp)bond through C-H activation and C-Br functionalization,and offers an effective and selective route to synthesizing highly valuable alkynylated isoquinolone,quinazolone and phthalazinonederivatives with a wide substrate scope and highselectivity.

关键词： Ru(Ⅱ) Alkynylation Isoquinolones Bromoalkynes Heterocyclic compounds C-H activation C-C coupling Synthetic methods

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Ru(II)-Catalyzed ortho C-H Allylation of N-Aryl-7-azaindoles with 2-Methylidene Cyclic Carbonate

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Chinese Journal of Chemistry 2024年第9期42卷 985-989页

作者： jing Zhang quan-Jian Luo Han-Chi Wang Jin-Heng Li Bo Sun State Key Laboratory Base of Eco-Chemical Engineering College of Chemical EngineeringQingdao University of Science and Technology QingdaoShandong266042China State key Laboratory of Applied Organic Chemistry Lanzhou University LanzhouGansu 7300ooChina School of Chemistry and Chemical Engineering Henan Normal UniversityXinxiangHenan 453007China

A Ru(II)-catalyzed ortho allylation reaction of N-aryl-7-azaindole with readily available 2-methylidene cyclic carbonate has been *** reaction is an effective pathway for synthesizing 7-azaindole derivatives with a wide scope of substrates and high *** addition,the method can be extended to the allylation of other heterocyclic compounds and several cyclic carbonates,highlighting the practicality of this strategy for synthesis.

关键词： Ru(II) Allylation N-Aryl-7-azaindoles Cyclic carbonates Heterocyclic compounds C-H activation

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