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A fast forward computational method for nuclear measurement using volumetric detection constraints

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Nuclear Science and Techniques 2024年第2期35卷 47-63页

作者： Qiong Zhang Lin-lv Lin University of Electronic Science and Technology of China Chengdu 610000China

Owing to the complex lithology of unconventional reservoirs,field interpreters usually need to provide a basis for interpretation using logging simulation *** the various detection tools that use nuclear sources,the detector response can reflect various types of information of the *** Monte Carlo method is one of the primary methods used to obtain nuclear detection responses in complex ***,this requires a computational process with extensive random sampling,consumes considerable resources,and does not provide real-time response ***,a novel fast forward computational method(FFCM)for nuclear measurement that uses volumetric detection constraints to rapidly calculate the detector response in various complex environments is ***,the data library required for the FFCM is built by collecting the detection volume,detector counts,and flux sensitivity functions through a Monte Carlo ***,based on perturbation theory and the Rytov approximation,a model for the detector response is derived using the flux sensitivity function method and a one-group diffusion *** environmental perturbation is constrained to optimize the model according to the tool structure and the impact of the formation and borehole within the effective detection ***,the method is applied to a neutron porosity tool for *** various complex simulation environments,the maximum relative error between the calculated porosity results of Monte Carlo and FFCM was 6.80%,with a rootmean-square error of 0.62 *** field well applications,the formation porosity model obtained using FFCM was in good agreement with the model obtained by interpreters,which demonstrates the validity and accuracy of the proposed method.

关键词： Nuclear measurement Fast forward computation Volumetric constraints

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制造业服务化与企业减排

经济评论 2023年第2期240卷 139-155页

作者：吕越陈泳昌华岳对外经济贸易大学国家(北京)对外开放研究院 100029 对外经济贸易大学中国WTO研究院 100029 湖南大学经济与贸易学院 410006

本文通过整合1998—2011年中国工业企业数据库和中国工业企业环境统计数据库两大微观数据库,并将其与基于世界投入产出数据库测算得到的制造业服务化数据进行合并,实证研究了制造业服务化对企业污染排放的影响。研究发现:制造业服务化... 详细信息

本文通过整合1998—2011年中国工业企业数据库和中国工业企业环境统计数据库两大微观数据库,并将其与基于世界投入产出数据库测算得到的制造业服务化数据进行合并,实证研究了制造业服务化对企业污染排放的影响。研究发现:制造业服务化水平的提高会显著降低企业的污染排放强度,这一结果在多方面的稳健性检验及内生性处理后依然显著成立。制造业服务化一方面通过优化企业的能源利用结构即降低煤炭能源依赖、提高清洁能源使用,发挥减排效应;另一方面通过显著促进企业技术进步和提升管理效率,降低污染排放强度。此外,外资企业和高能耗企业更能通过制造业服务化实现减排效果,国内上游服务市场的质量提升和成本下降也会显著降低下游制造业企业的污染排放强度。本文研究对加快我国工业企业发展方式绿色转型具有积极意义。

关键词：制造业服务化企业污染排放能源结构优化技术进步管理效率

Sclerosing angiomatoid nodular transformation of the spleen: A case report and literature review

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World Journal of Clinical Cases 2021年第1期9卷 211-217页

作者： Shu-Xuan Li Ye-Hui Fan Hao Wu Guo-yue lv Department of Hepatobiliary and Pancreatic Surgery First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina Department of The First Operation Room First Hospital of Jilin UniversityChangchun 130021Jilin ProvinceChina

BACKGROUND Sclerosing angiomatoid nodular transformation(SANT)is a rare disease of the *** has unique pathological features and mimics splenic tumor on radiological *** SUMMARY A 47-year-old woman was incidentally found to have a splenic mass on abdominal *** had a 10-cm postoperative scar in the lower abdomen due to previous cesarean *** patient had a past history of anemia of unknown etiology for 20 *** patient underwent laparoscopic *** postoperative course was uneventful,with a hospital stay of 7 *** histopathological examination of the spleen revealed *** the 6-mo followup,the patient remained *** SANT is a rare benign disease mimicking a malignant tumor.A definitive diagnosis can be made only on histopathology.

关键词： Splenic neoplasms Sclerosing angiomatoid nodular transformation Spleen Case report

Chlorajaponins A—Q,Lindenane-Related Sesquiterpenoid Dimers from Chloranthus japonicus and Their Biological Activities

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Chinese Journal of Chemistry 2024年第11期42卷 1247-1259页

作者： Wei-Jiao Feng yue Gu Pei-Zhi Huang Hong-Ying Yang Rui Zhang Yi-Lin He Ting-Hong lv Ya Li Kun Gao State Key Laboratory of Applied Organic Chemistry College of Chemistry and Chemical EngineeringLanzhou UniversityLanzhouGansu730000 China Research Institute Lanzhou Jiaotong UniversityLanzhouGansu730070 China

Seventeen undescribed lindenane-related sesquiterpenoid dimers,chlorajaponins A—Q(1—17),and 13 reported analogs(18—30)were isolated from Chloranthus japonicus *** 1 possesses an unprecedented 3/5/7/5/5/6/5/3 fused octacyclic scaffold,featuring a 6(5→4)-abeo-lindenane monomer,while 2 exhibits a 3/5/6/6/5/6/5/3 fused octacyclic *** structures were determined through a combination of spectroscopic analyses and X-ray *** 1,2,and 18 demonstrated significant inhibitory effects on lipid accumulation and effectively reduced the levels of triglycerides and total cholesterol,as well as the levels of aspartate aminotransferase and alanine aminotransferase in a HepG2 cell *** addition,compounds 1,2,and 18 significantly suppressed the protein expression of the fatty acid synthase(FASN)and the sterol regulatory element-binding protein 1(SREBP1).Moreover,the anti-inflammatory assay showed that compounds 19—22 and 25 inhibited the NO production induced by lipopolysaccharide in RAW 264.7 macrophages with IC50 values of 7.89±0.44,6.25±0.46,2.98±0.29,10.77±0.60,and 3.60±0.28μmol/L.

关键词： Chloranthus japonicus Lindenane-type sesquiterpenoid dimers Lipid-lowering activity Anti-inflammatory activity NMR spectroscopy Natural products X-ray diffraction

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上游服务业开放与制造业企业的环境污染

财贸经济 2022年第6期43卷 114-127页

作者：吕越陈泳昌对外经济贸易大学国际经济贸易学院 100029 对外经济贸易大学中国世界贸易组织研究院 100029

推动开放发展和绿色发展是贯穿“十四五”时期我国经济高质量发展和培育形成国际竞争新优势的重要发展理念。本文通过整合1998—2013年中国工业企业数据库及中国工业企业污染排放数据库获得了高度细化的微观企业数据,再将其与基于《外... 详细信息

推动开放发展和绿色发展是贯穿“十四五”时期我国经济高质量发展和培育形成国际竞争新优势的重要发展理念。本文通过整合1998—2013年中国工业企业数据库及中国工业企业污染排放数据库获得了高度细化的微观企业数据,再将其与基于《外商投资产业指导目录》和投入产出表构建的上游服务业开放指标进一步合并,实证研究了我国上游服务业开放对企业污染的影响效应及内在机制。研究发现,首先,服务业开放会显著降低企业污染水平,这一结论在多重稳健性检验及内生性处理后依然显著成立;其次,服务业开放主要通过降低投入中的能源依赖和推动生产中的技术进步两个方面来改善企业环境绩效;最后,能源消耗水平、服务依赖度更高的企业以及技术密集型行业内企业更能依托服务业开放发挥环境改善效应。本文研究结论揭示了我国扩大服务业开放进程中的生态环境效应,为进一步推动开放发展战略与绿色发展新理念的耦合与兼容提供了有益的经验证据和政策启示。

关键词：服务业开放制造业企业环境污染

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

Trade Barriers and Participation in the Global Value Chain:An Empirical Study Based on Anti-dumping toward China

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China & World Economy 2019年第2期27卷 86-106页

作者： Xiaosong Wang Zhexi Liu yue lv Chunming Zhao School of Economics Renmin University of China School of International Trade and Economics University of International Business and EconomicsChina China Institute for WTO Studies University of International Business and EconomicsChina Business School Beijing Normal UniversityChina

This paper investigates the effects of trade barriers on China s participation in the global value chain(GVC)using a thorough decomposition approach for trade volume,total exports,final exports and intermediate *** econometric results indicate that anti-dumping(AD)measures initiated by trade partners have restrained the process of China s participation in the *** 2000 to 2014,AD measures reduced the foreign value-added rate of total,final and intermediate exports by 4.5 to 28.7 percent,3.4 to 17 percent and 1.2 to 8.5 percent,*** addition,suffering the effects of AD measures,China s GVC position index declined by 8.2 percent to 28.6 percent during this ***,AD measures have increased industries'upstream index by 3.2 to 13.7 percent over the same *** results imply that both the petition and approval of AD cases has had a negative influence on the extent and position of China s GVC participation.

关键词： anti-dumping foreign value-added rate global value chain technology upgrading

Control of chiral-optical activities by magnetic field based on the transformation of achiral binary crystals into chiral ternary crystals

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Science China Chemistry 2024年第7期67卷 2300-2305页

作者： Zhiyan Chen Yan lv Wei Qin College of Physics Qingdao UniversityQingdao 266071China School of Physics State Key Laboratory of Crystal MaterialsShandong UniversityJinan 250100China Shandong Linuo Photovoltaic Hi-Tech Co. Ltd.Jinan 250100China

Multicomponent self-assembled chiral systems have attracted great attention due to their promising application in the area of spin-photonics and *** this work,through introducing an achiral third component into an achiral binary crystal,a chiral organic ternary crystal is fabricated,where both pronounced chiral-optical coupling and magnetic field dependence of chiral-optical activities are *** transformation of achiral structure into chiral structure generates a significant effect on the polarized state of light and the electron spin resonance ***,the coupling between circularly polarized photon and spin is observed in chiral ternary crystal with pronounced chiral orbit,where obvious magnetic field-transmissivity loop is ***,temperature could increase the magnitude of lattice parameters to lead to a larger helix radius to increase the chiral orbit ***,this work indicates that the further exploration of photon-chiral orbit-spin interactions in organic chiral ternary crystals is promising.

关键词： organic chiral ternary crystals chiral orbit chiral-optical activities magnetic field

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Event-triggered sliding mode control of linear repetitive processes and its application in metal rolling process

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Science China(Information Sciences) 2024年第3期67卷 167-181页

作者： Xinyu lv Yugang NIU James LAM Key Laboratory of Smart Manufacturing in Energy Chemical Process (East China University of Science and Technology) Ministry of Education Department of Mechanical Engineering The University of Hong Kong

This paper investigates the design problem of a sliding mode controller for linear repetitive processes(LRPs) with a finite pass length on each pass. Under limited communication resources, an eventtriggered mechanism is implemented from the sensors to the controller, whose triggered sequence is consistent with the evolution direction of LRPs. To periodically orchestrate communication between the controller and actuator, a round-robin scheduling mechanism is established based on the pass length. A sliding function involving the state and pass profile is constructed, and the sliding mode controller is designed using triggered states and pass profile signals. Feasible controller gains are attained to ensure the stability of the resultant closed-loop system. Finally, the proposed strategy is implemented for a multi-roll metal rolling process.

关键词： event-triggered mechanism linear repetitive processes metal rolling process round-robin scheduling sliding mode control

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