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Design and synthesis of thiol-terminated imidothioether oligomer as thermally latent hardener and modifier for high-performance epoxy/thiol thermosets

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Science China Chemistry 2024年第2期67卷 632-641页

作者： xing liu Jianjun Zhou Shumei liu Jianqing Zhao School of Materials Science and Engineering South China University of TechnologyGuangzhou510640China Key Lab Guangdong High Property&Functional Polymer Materials Key Laboratory of Polymer Processing EngineeringMinistry of EducationGuangzhou510640China

Conventional base-catalyzed epoxy/aliphatic thiol systems have a poor storage stability,and are impossible to be one-pot systems.A widely accepted solution is to use the latent catalysts,which are usually insoluble anionic initiators sensitive to impurities and moisture,and have many limitations in practical *** this work,a soluble thiol-terminated imidothioether oligomer(TPI) was synthesized and used as a latent hardener and modifier to prepare one-pot epoxy/thiol systems without the latent *** latent behavior and curing mechanism of epoxy systems(EP/TPI series),consisted of bisphenol A diglycidyl ether(DGEBA),pentaerythritol tetrakis(mercaptoacetate)(PETMP) and TPI,were *** thiol exchange reaction between TPI and PETMP preceded the curing reaction of DGEBA,and produced aromatic thiols,which were unreactive at ambient conditions and reacted with DGEBA to form the thermosets at temperatures above 130 ℃.At the loading of 24.4 wt%TPI,the epoxy system(EP/TPI-3) had a shelf life of 13 days and was completely cured within 20 min at 180 ℃.Meanwhile,the catalyst-free curing process of EP/TPI-3 system was insensitive to impurities and ***,the thermal and mechanical properties of EP/TPI-3 thermoset were simultaneously improved,thereinto,the glass transition temperature,Young's modulus and ultimate tensile strength were increased by 16.7 ℃,12.9%,and 13.6%,respectively,compared with those of the commercial DGEBA/PETMP *** work shows that TPI has the potential to be a powerful alternative to commercial latent catalysts,and EP/TPI thermosets with high performance have broad application prospects.

关键词： thiol-terminated imidothioether oligomer epoxy systems thiol exchange reaction thermal latency high performance

Pd Pt VO_(x)/CeO_(2)-ZrO_(2):Highly efficient catalysts with good sulfur dioxide-poisoning reversibility for the oxidative removal of ethylbenzene

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Journal of Environmental Sciences 2024年第4期138卷 153-166页

作者： Jia Wang yuxi liu Jiguang Deng Lin Jing Xiuqing Hao xing Zhang Xiaohui yu Hongxing Dai Beijing Key Laboratory for Green Catalysis and Separation Key Laboratory of Beijing on Regional Air Pollution ControlKey Laboratory of Advanced Functional MaterialsEducation Ministry of ChinaLaboratory of Catalysis Chemistry and NanoscienceDepartment of Chemical EngineeringFaculty of Environment and LifeBeijing University of TechnologyBeijing 100124China

The PdPtVO_(x)/CeO_(2)-ZrO_(2)(PdPtVO_(x)/CZO)catalysts were obtained by using different approaches,and their physical and chemical properties were determined by various *** activities of these materials in the presence of H_(2)O or SO_(2)were evaluated for the oxidation of ethylbenzene(EB).The PdPtVO_(x)/CZO sample exhibited high catalytic activity,good hydrothermal stability,and reversible sulfur dioxide-poisoning performance,over which the specific reaction rate at 160℃,turnover frequency at 160℃(TOF_(Pd or Pt)),and apparent activation energy were 72.6 mmol/(g_(Pt)·sec)or 124.2 mmol/(g_(Pd)·sec),14.2 sec^(-1)(TOF_(Pt))or 13.1 sec^(-1)(TOF_(Pd)),and 58 k J/mol,*** large EB adsorption capacity,good reducibility,and strong acidity contributed to the good catalytic performance of PdPtVO_(x)/*** activity of PdPtVO_(x)/CZO decreased when 50 ppm SO_(2)or(1.0 vol.%H_(2)O+50 ppm SO_(2))was added to the feedstock,but was gradually restored to its initial level after the SO_(2)was cut *** good reversible sulfur dioxide-resistant performance of PdPtVO_(x)/CZO was associated with the facts:(i)the introduction of SO_(2)leads to an increase in surface acidity;(ii)V can adsorb and activate SO_(2),thus accelerating formation of the SO_(x)^(2-)(x=3 or 4)species at the V and CZO sites,weakening the adsorption of sulfur species at the PdPt active sites,and hence protecting the PdPt active sites to be not poisoned by SO_(2).EB oxidation over PdPtVO_(x)/CZO might take place via the route of EB→styrene→phenyl methyl ketone→benzaldehyde→benzoic acid→maleic anhydride→CO_(2)and H_(2)O.

关键词： Ceria-zirconia Supported palladium-platinum-vanadium catalyst Volatile organic compound Ethylbenzene oxidation Sulfur dioxide resistance

Histone methylation in pancreatic cancer and its clinical implications

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World Journal of Gastroenterology 2021年第36期27卷 6004-6024页

作者： xing-yu liu Chuan-Hao Guo Zhi-yuan Xi Xin-Qi Xu Qing-Yang Zhao Li-Sha Li Ying Wang The First Hospital of Jilin University Jilin UniversityChangchun 130021Jilin ProvinceChina The Key Laboratory of Pathobiology Ministry of EducationCollege of Basic Medical SciencesJilin UniversityChangchun 130021Jilin ProvinceChina

Pancreatic cancer(PC)is an aggressive human *** methods for the diagnosis and treatment of PC have not been found at the genetic level,thus making epigenetics a promising research path in studies of *** methylation is one of the most complicated types of epigenetic modifications and has proved crucial in the development of *** methylation is a reversible process regulated by readers,writers,and *** writers and erasers can be recognized as potential biomarkers and candidate therapeutic targets in PC because of their unusual expression in PC cells compared with normal pancreatic *** on the impact that writers have on the development of PC,some inhibitors of writers have been ***,few inhibitors of erasers have been developed and put to clinical ***,there is not enough research on the reader ***,the study of erasers and readers is still a promising *** review focuses on the regulatory mechanism of histone methylation,and the diagnosis and chemotherapy of PC based on *** future of epigenetic modification in PC research is also discussed.

关键词： Pancreatic cancer Epigenetics Histone modification Methylation Demethylation Clinical application

A Novel Foreign Object Detection Method in Transmission Lines Based on Improved YOLOv8n

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Computers, Materials & Continua 2024年第4期79卷 1263-1279页

作者： Yakui liu xing Jiang Ruikang Xu Yihao Cui Chenhui yu Jingqi Yang Jishuai Zhou School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao266520China State Key Laboratory of Electrical Insulation and Power Equipment Xi’an Jiaotong UniversityXi’an710049China Key Lab of Industrial Fluid Energy Conservation and Pollution Control Qingdao University of TechnologyMinistry of EducationQingdao266520China

The rapid pace of urban development has resulted in the widespread presence of construction equipment andincreasingly complex conditions in transmission corridors. These conditions pose a serious threat to the safeoperation of the power *** vision technology, particularly object recognition technology, has beenwidelyemployed to identify foreign objects in transmission line images. Despite its wide application, the technique faceslimitations due to the complex environmental background and other auxiliary factors. To address these challenges,this study introduces an improved YOLOv8n. The traditional stepwise convolution and pooling layers are replacedwith a spatial-depth convolution (SPD-Conv) module, aiming to improve the algorithm’s efficacy in recognizinglow-resolution and small-size objects. The algorithm’s feature extraction network is improved by using a LargeSelective Kernel (LSK) attention mechanism, which enhances the ability to extract relevant features. Additionally,the SIoU Loss function is used instead of the Complete Intersection over Union (CIoU) Loss to facilitate fasterconvergence of the algorithm. Through experimental verification, the improved YOLOv8n model achieves adetection accuracy of 88.8% on the test set. The recognition accuracy of cranes is improved by 2.9%, which isa significant enhancement compared to the unimproved algorithm. This improvement effectively enhances theaccuracy of recognizing foreign objects on transmission lines and proves the effectiveness of the new algorithm.

关键词： YOLOv8n data enhancement attention mechanism SPD-Conv Smoothed Intersection over Union(SIoU)Loss

Enhanced Cooling Efficiency of Urban Trees on Hotter Summer Days in 70 Cities of China

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Advances in Atmospheric Sciences 2024年第11期41卷 2259-2275页

作者： Limei YANG Jun GE Yipeng CAO yu liu xing LUO Shiyao WANG Weidong GUO School of Atmospheric Sciences Nanjing UniversityNanjing 210023China Joint International Research Laboratory of Atmospheric and Earth System Sciences Nanjing UniversityNanjing 210023China Frontiers Science Center for Critical Earth Material Cycling Nanjing UniversityNanjing 210023China

Increasing the urban tree cover percentage(TCP) is widely recognized as an efficient way to mitigate the urban heat island effect. The cooling efficiency of urban trees can be either enhanced or attenuated on hotter days, depending on the physiological response of urban trees to rising ambient temperature. However, the response of urban trees' cooling efficiency to rising urban temperature remains poorly quantified for China's cities. In this study, we quantify the response of urban trees' cooling efficiency to rising urban temperature at noontime [~1330 LT(local time), LT=UTC+8] in 17summers(June, July, and August) from 2003–19 in 70 economically developed cities of China based on satellite observations. The results show that urban trees have stronger cooling efficiency with increasing temperature, suggesting additional cooling benefits provided by urban trees on hotter days. The enhanced cooling efficiency values of urban trees range from 0.002 to 0.055℃ %-1 per 1℃ increase in temperature across the selected cities, with larger values for the lowTCP-level cities. The response is also regulated by background temperature and precipitation, as the additional cooling benefit tends to be larger in warmer and wetter cities at the same TCP level. The positive response of urban trees' cooling efficiency to rising urban temperature is explained mainly by the stronger evapotranspiration of urban trees on hotter *** results have important implications for alleviating urban heat risk by utilizing urban trees, particularly considering that extreme hot days are becoming more frequent in cities under global warming.

关键词： urban trees cooling efficiency China's cities evapotranspiration summer hot days

An improved analysis method for assessing the nuclear-heating impact on the stability of toroidal field magnets in fusion reactors

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Nuclear Science and Techniques 2024年第6期35卷 163-176页

作者： yu-Dong Lu Jin-xing Zheng Xu-Feng liu Huan Wu Jian Ge Kun Xu Ming Li Hai-Yang liu Lei Zhu Fei liu Institute of Plasma Physics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China University of Science and Technology of China Hefei 230026China

The superconducting magnet system of a fusion reactor plays a vital role in plasma confinement,a process that can be dis-rupted by various operational factors.A critical parameter for evaluating the temperature margin of superconducting magnets during normal operation is the nuclear heating caused by D-T *** study investigates the impact of nuclear heat-ing on a superconducting magnet system by employing an improved analysis method that combines neutronics and thermal *** the magnet system,toroidal field(TF)magnets are positioned closest to the plasma and bear the highest nuclear-heat load,making them prime candidates for evaluating the influence of nuclear heating on *** enhance the modeling accuracy and facilitate design modifications,a parametric TF model that incorporates heterogeneity is established to expedite the optimization design process and enhance the accuracy of the computations.A comparative analysis with a homogeneous TF model reveals that the heterogeneous model improves accuracy by over 12%.Considering factors such as heat load,magnetic-field strength,and cooling conditions,the cooling circuit facing the most severe conditions is selected to calculate the temperature of the *** selection streamlines the workload associated with thermal-hydraulic *** approach enables a more efficient and precise evaluation of the temperature margin of TF ***,it offers insights that can guide the optimization of both the structure and cooling strategy of superconducting magnet systems.

关键词： Superconducting magnet Nuclear heating Neutronics Thermal hydraulics

Tumor microenvironment-responsive arsenic-loaded layered double hydroxides film with synergistic anticancer and bactericidal activity

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Rare Metals 2024年第3期43卷 1207-1221页

作者： Shun xing Dong-Hui Wang Hai-Feng Zhang Li-Dan liu Cheng-Ce Li Chao Wei Jun-yu liu Nai-Jian Ge Xuan-Yong liu State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing100049China Intervention Center Eastern Hepatobiliary Surgery HospitalThe Third Affiliated Hospital of Naval Medical UniversityShanghai200438China School of Health Sciences and Biomedical Engineering Hebei University of TechnologyTianjin300130China

Malignant obstruction makes gallbladder cancer have a high mortality ***-titanium alloy(nitinol)stents are commonly used as a local intervention to maximize patient survival time,but the stents lack antitumor and antibacterial capacity and are vulnerable to secondary ***-based drugs show good therapeutic promise against gallbladder *** meet clinical *** layered double hydroxides(LDHs)film is constructed on the nitinol,whose arsenite loading amounts rose by 60%after simple heat treatment compared with the conventional anion-exchange *** addition,calcination promotes the dissolution of nickel ions from the LDHs lattice,resulting in a powerful synergistic killing effect on tumor cells together with the released *** importantly,the calcined arsenic-loaded LDHs are sensitive to the acidic microenvironment of tumor tissues,which presents a much lower arsenic and nickel release amount in the normal tissues,guaranteeing its ***,the vertically sharp LDHs nanosheets can synergize with arsenic to achieve effective physical cleavage and chemical killing of adherent and planktonic *** short,we attempt to use arsenic drugs for local interventions and reasonably avoid their toxic side effects,which provides a new design idea for nitinol stents applied in the treatment of gallbladder cancer.

关键词： Nitinol Layered double hydroxides Arsenic Gallbladder cancer

Eosinophilic granulomatosis with polyangiitis,asthma as the first symptom,and subsequent Loeffler endocarditis:A case report

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世界临床病例杂志 2023年第27期11卷 6523-6530页

作者： Jia-Ling He xing-yu liu Yi Zhang Li Niu Xin-Lin Li xing-yu Xie Yang-Ting Kang Lan-Qing Yang Zheng-Yang Cai Hui Long Guang-Fei Ye Jun-Xin Zou Department of Emergency Affiliated Hospital of Guizhou Medical UniversityGuiyang 550001Guizhou ProvinceChina Department of Orthopedic Surgery Affiliated Hospital of Guizhou Medical UniversityGuiyang 550001Guizhou ProvinceChina Department of Internal Cardiovascular Medicine Affiliated Hospital of Guizhou Medical UniversityGuiyang 550001Guizhou ProvinceChina Department of Medical Cosmetology Beijing Puxiang Traditional Chinese Medicine HospitalBeijing 100080China College of Pediatrics Guizhou Medical UniversityGuiyang 550001Guizhou ProvinceChina Department of Internal Cardiovascular Medicine People’s Hospital of Baiyun DistrictGuiyang 550014Guizhou ProvinceChina Department of Orthopedic Surgery Hospital of Guizhou Panjiang Coal Power Group Limited Liability CompanyLiupanshui 553537Guizhou ProvinceChina Department of Imaging Affiliated Hospital of Guizhou Medical UniversityGuiyang 550001Guizhou ProvinceChina

BACKGROUND Eosinophilic granulomatosis with polyangiitis(EGPA),formerly known as Churg-Strauss syndrome,is a rare form of anti-neutrophil cytoplasmic antibodyassociated vasculitis characterized by asthma,vasculitis,and *** SUMMARY We report an atypical case of EGPA in a 20-year-old female *** previously reported cases of EGPA,this patient’s initial symptom was asthma associated with a respiratory *** was followed by Loeffler endocarditis and cardiac *** received treatment with methylprednisolone sodium succinate,low molecular weight heparin,recombinant human brain natriuretic peptide,furosemide,cefoperazone sodium/sulbactam sodium,and *** prophylactic anticoagulation,she developed a large right ventricular *** diagnosis was confirmed based on ancillary test results and specialty *** treatment included mycophenolate *** overall condition improved significantly after treatment,as evidenced by decreased peripheral blood eosinophils and cardiac *** was discharged after 17 *** most recent follow-up showed normal peripheral blood eosinophil levels,restored cardiac function,and a reduced cardiac mural thrombus *** This case illustrates the swift progression of EGPA and underscores the significance of early detection and immediate intervention to ensure a favorable prognosis.

关键词： Churg-Strauss syndrome Anti-neutrophil cytoplasmic antibody-associated vasculitis Eosinophilia Loeffler endocarditis Asthma Case report

Treatment of bilateral developmental dysplasia of the hip joint with an improved technique:A case report

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World Journal of Clinical Cases 2024年第7期12卷 1320-1325页

作者： xing-xing yu Jian-Ye Chen Hong-Sheng Zhan Ming-Da liu yun-Fei Li yu-Yan Jia College of Traditional Chinese Medicine Changchun University of Traditional Chinese MedicineChangchun 130117Jilin ProvinceChina Shi's Traumatology Medical Center Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese MedicineShanghai 201203China College of Traditional Chinese Medicine The Affiliated Hospital of Changchun University of Chinese MedicineChangchun 130021Jilin ProvinceChina

BACKGROUND Developmental dysplasia of the hip(DDH)is a common osteoarticular deformity in pediatric orthopedics.A patient with bilateral DDH was diagnosed and treated using our improved technique"(powerful overturning acetabuloplasty)"combined with femoral rotational shortening *** SUMMARY A 4-year-old girl who was diagnosed with bilateral DDH could not stand normally,and sought surgical treatment to solve the problem of double hip extension and *** this child had high dislocation of the hip joint and the acetabular index was high,we changed the traditional acetabuloplasty to"powerful turnover acetabuloplasty"combined with femoral rotation shortening *** the short-term postoperative follow-up(1,3,6,9,12,and 15 months),the child had no discomfort in her lower *** the braces and internal fixation plates were removed,formal rehabilitation training was actively carried *** Our"powerful overturning acetabuloplasty"combined with femoral rotational shortening osteotomy is feasible in the treatment of DDH in *** technology may be widely used in the clinic.

关键词： Developmental dysplasia of the hip Improved technique Case report