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Design and preparation of a crosslinkable,oil-resistant,and bio-based elastomer from fumarate

Science China Chemistry 2024年第2期67卷 622-631页

作者： Hui Yang Haijun Ji Xinxin Zhou Shihan Yang liwei li Chaoying Sun Weiwei Lei Runguo Wang liqun Zhang Beijing State Key Laboratory of Organic-Inorganic Composites&Beijing Laboratory of Biomedical Materials Beijing University of Chemical TechnologyBeijing100029China Hubei Key Laboratory of Polymer Materials Faculty of Materials Science and EngineeringHubei UniversityWuhan430062China

Poly(diethyl fumarate-co-methoxyethyl acrylate-co-vinyl chloroacetate)(PDEFMV),a novel bio-based elastomer with a saturated structure,was synthesized via redox emulsion polymerization.The glass-transition temperatures of PDEFMV,adjusted through the variation of the diethyl fumarate-to-methoxyethyl acrylate feeding ratio,ranged from-36.1 to-14.8 ℃.The number-average molecular weights of PDEFMV ranged from 384,000 to 46,000 g/mol.In designing the molecular structure,vinyl chloroacetate was used to provide active sites for subsequent vulcanization and crosslinking.The active chlorine groups within the PDEFMV chain reacted with the crosslinking agent trithiocyanuric acid under high temperature and pressure to form a nonsulfur crosslinked three-dimensional network structure.To achieve the desired properties,carbon black(CB,N330) was incorporated to reinforce PDEFMV,leading to the formation of PDEFMV/CB composites.A comprehensive study was conducted on the high-temperature oil resistance of PDEFMV/CB composites.Following immersion in IRM903 oil at temperatures of 150 and 200 ℃ for 72 h,the mass and volume changes in PDEFMV/CB were lower than those observed in commercially available acrylate rubber(AR)/CB,indicating that PDEFMV exhibited superior oil resistance.Furthermore,the aging characteristics and mechanisms of oil resistance in the PDEFMV/CB and AR/CB composites were investigated at different temperatures(150,200,and 250 ℃).The results provide insights into the operational temperature ranges suitable for PDEFMV/CB and offer valuable guidance for potential industrial applications.

关键词： diethyl fumarate molecular design bio-based elastomer solvent-free synthetic route high-temperature oil resistance

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Sequential Growth of Cs_(3)Bi_(2)I_(9)/BiVO_(4)Direct Z-Scheme Heterojunction for Visible-light-Driven Photocatalytic CO_(2)Reduction

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Transactions of Tianjin University 2023年第6期29卷 462-472页

作者： Long Jiang Hanrui Du Le li Xiangjiu Guan Yihao Zhang liwei li Xiaoxu liu Lei li Yingcheng Tian li Zhang Shuai Wang Jie Chen Shaohua Shen State Key Laboratory for Performance and Structure Safety of Petroleum Tubular Goods and Equipment Materials CNPC Tubular Goods Research InstituteXi’an 710077China International Research Center for Renewable Energy State Key Laboratory of Multiphase Flow in Power EngineeringXi’an Jiaotong UniversityXi’an 710049China School of Chemical Engineering and Technology Xi’an Jiaotong UniversityXi’an 710049China CNPC National Engineering Research Center for Oil and Gas Drilling Equipment Co. Ltd.Baoji 721002China China Coal Energy Research Institute Co. Ltd.Xi’an 710049China

The high exciton binding energy and lack of a positive oxidation band potential restrict the photocatalytic CO_(2)reduction efficiency of lead-free Bi-based halide perovskites Cs_(3)Bi_(2)X_(9)(X=Br,I).In this study,a sequential growth method is presented to prepare a visible-light-driven(λ>420 nm)Z-scheme heterojunction photocatalyst composed of BiVO_(4)nanocrystals decorated on a Cs_(3)Bi_(2)I_(9)nanosheet for photocatalytic CO_(2)reduction coupled with water oxidation.The Cs_(3)Bi_(2)I_(9)/BiVO_(4)Z-scheme heterojunction photocatalyst is stable in the gas-solid photocatalytic CO_(2)reduction system,demonstrating a high visible-light-driven photocatalytic CO_(2)-to-CO production rate of 17.5μmol/(g·h),which is approximately three times that of pristine Cs_(3)Bi_(2)I_(9).The high efficiency of the Cs_(3)Bi_(2)I_(9)/BiVO_(4)heterojunction was attributed to the improved charge separation in Cs_(3)Bi_(2)I_(9).Moreover,the Z-scheme charge-transfer pathway preserves the negative reduction potential of Cs_(3)Bi_(2)I_(9)and the positive oxidation potential of BiVO_()4.This study off ers solid evidence of constructing Z-scheme heterojunctions to improve the photocatalytic performance of lead-free halide perovskites and would inspire more ideas for developing leadfree halide perovskite photocatalysts.

关键词： Lead-free halide perovskite Z-scheme heterojunction CO_(2)reduction Visible-light photocatalysis Charge transfer

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Characteristics of molecular classification in 52 endometrial cancer and atypical hyperplasia patients receiving fertility-sparing treatment

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Gynecology and Obstetrics Clinical Medicine 2023年第1期3卷 38-43页

作者： Yiqin Wang Nan Kang liwei li Zhiqi Wang Rong Zhou Danhua Shen Jianliu Wang Department of Obstetrics and Gynecology Peking University People's HospitalBeijing100044China Department of Pathology Peking University People's HospitalBeijing100044China

Objective To investigate the molecular classification of endometrial cancer(EC)and atypical endometrial hyperplasia(AEH)patients treated with fertility-sparing treatment(FST),and its relationship with clinicopathological factors and treatment efficacy.Methods:A total of 52EC and AEH patients who received FST and molecular classification tested by next generation sequencing in Peking University People's Hospital from June 2020 to December 2022,were retrospectively collected.We analyzed the relationship between molecular classification and clinicopathological factors and treatment outcomes.Results(1)Of the 52 patients,including 46EC and 6 AEH patients,42(80.8%)achieved complete remission(CR)after FST,with a median time to achieve CR of 9 months.Ten cases(23.8%)had recurrence.(2)Patients were distributed into 4 molecular subgroups as 39 cases(75%)of copy number low(CNL),7 cases(13.5%)of microsatellite instability-high(MSI-H),4 cases(7.7%)of POLE mutations(POLEmut),and 2 cases(3.8%)of copy number high(CNH).Patients with MSI-H subgroup had more family history of tumor(6/7),more with loss of expression of mismatch repair(MMR)protein(7/7),and higher expression level of Ki-67(3/3).(3)Patients with MSI-H subgroup had the lowest CR rate at 6 months(0/7,P=0.014),and survival analysis showed that such patients were less likely to achieve CR than those with CNL(P=0.022).For CNL patients,median 6-month CR rate was 40.6%.In addition,CR was obtained in 3(3/4)POLEmut patients and 2(2/2)CNH patients,respectively.Conclusions Molecular classification relates with the treatment response in patients with EC and AEH receiving FST.Patients with MSI-H subgroup have poor treatment efficacy,and patients with CNL need to be further divided to predict treatment benefit.There are also a few successful cases in POLEmut and CNH subtgroups,which needs further research.

关键词： Endometrial cancer Fertility-sparing Progesterone Molecular classification Efficacy

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Synthesis of hydrophobic carbon nanotubes/reduced graphene oxide composite films by flash light irradiation

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Frontiers of Chemical Science and Engineering 2018年第3期12卷 376-382页

作者： Kai Wang Jinbo Pang liwei li Shengzhe Zhou Yuhao li Tiezhu Zhang College of Automation and Electric Engineering Qingdao University Qingdao 266071 China The Leibniz Institute for Solid State and Materials Research Dresden (IFW Dresden) Dresden D-01069 Germany

Carbon nanotubes/graphene composites have superior mechanical, electrical and electrochemistry prop- erties with carbon nanotubes as a hydrophobicity boosting agent. Their extraordinary hydrophobic performance is highly suitable for electrode applications in lithium ion batteries and supercapacitors which often employ organic electrolytes. Also the hydrophobic features enable the oil enrichment for the crude oil separation from seawater. The ever reported synthesis routes towards such a composite either involve complicated multi-step reactions, e.g., chemical vapor depositions, or lead to insufficient extru- sion of carbon nanotubes in the chemical reductions of graphene oxide, e.g., fully embedding between the compact graphene oxide sheets. As a consequence, the formation of standalone carbon nanotubes over graphene sheets remains of high interests. Herein we use the facile flash light irradiation method to induce the reduction of graphene oxides in the presence of carbon nanotubes. Photographs, micrographs, X-ray diffraction, infrared spectroscopy and thermogravimetric analysis all indicate that graphene oxides has been reduced. And the contact angle tests confirm the excellent hydrophobic perfor- mances of the synthesized carbon nanotube/reduced graphene oxide composite films. This one-step treatment represents a straightforward and high efficiency way for the reduction of carbon nanotubes/graphene oxides composites.

关键词： carbon nanotubes graphene composite flash irradiation method reduced graphene oxide contact angles

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沂水县浅层地下水水化学特征及人体健康风险评估

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环境科学学报 2024年第3期44卷 177-188页

作者：李立伟许庆陈秀增李宜蓉临沂市沂水县环境监控中心临沂276400 沂水县交通运输局临沂276400

地下水是山东省沂水县及其周边地区饮用水和灌溉用水的主要来源.厘清地下水化学特征及其水质状况,对防止其恶化和区域性开发利用与保护具有十分重要的意义.本研究基于沂水县全域447个地下水样本的层次聚类分析,采用Piper三线图和Gibbs... 详细信息

地下水是山东省沂水县及其周边地区饮用水和灌溉用水的主要来源.厘清地下水化学特征及其水质状况,对防止其恶化和区域性开发利用与保护具有十分重要的意义.本研究基于沂水县全域447个地下水样本的层次聚类分析,采用Piper三线图和Gibbs图等图形方法揭示了研究区域地下水化学特征及其演变机制,并通过熵权水质指数(EWQI)对地下水水质进行了评估.结果表明,各聚类模块中地下水整体水质优良,符合国家饮用水水质标准.Na^(+)、SO_(4)^(2-)、Cl^(-)、NH_(4)^(+)-N、NO_(3)^(-)-N和F-的变异系数较大,且NH_(4)^(+)-N、SO_(4)^(2-)、F-以及Cl^(-)对地下水水质的贡献较大,约占55%.地下水水化学类型以HCO_(3)-Mg·Ca为主,影响地下水化学演变的主导因素为岩石风化和溶解.成人的健康风险结果显示,仅Cluster C和Cluster B中存在非致癌风险超过1.0(HI>1)的可接受限值的地下水样本,且其比例均低于20%(分别为18.84%和6.52%),而儿童的这一比例在Cluster C和Cluster B中也较高,且所有聚类模块中均存在HI>1的样本.地下水的非致癌风险在Cluster C和Cluster B中较高,且口服摄入是影响研究区成人和儿童健康风险的最重要途径.地下水水质评价和健康风险评估为区域地下水的可持续发展和污染防治提供了理论参考.

关键词：地下水水化学特征形成机制健康风险评估沂水县

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A thermally flexible and multi-site tactile sensor for remote 3D dynamic sensing imaging

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Frontiers of Chemical Science and Engineering 2020年第6期14卷 1039-1051页

作者： Guoting Xia Yinuo Huang Fujiang li licheng Wang Jinbo Pang liwei li Kai Wang School of Electrical Engineering Qingdao UniversityQingdao 266000China Department of Pediatric Surgery Affiliated Hospital of Qingdao UniversityQingdao 266000China College of Information Engineering Zhejiang University of TechnologyHangzhou 310023China Collaborative Innovation Center of Technology and Equipment for Biological Diagnosis and Therapy in Universities of Shandong Institute for Advanced Interdisciplinary Research(iAIR)Jinan UniversityJinan 250022China

A flexible,multi-site tactile and thermal sensor(MTTS)based on polyvinylidene fluoride(resolution 50×50)is reported.It can be used to implement spatial mapping caused by tactile and thermal events and record the two-dimensional motion trajectory of a tracked target object.The output voltage and current signal are recorded as amapping by sensing the external pressure and thermal radiation stimulus,and the response distribution is dynamically observed on the three-dimensional interface.Through the mapping relationship between the established piezoelectric and pyroelectric signals,the piezoelectric component and the pyroelectric component are effectively extracted from the composite signals.The MTTS has a good sensitivity for tactile and thermal detection,and the electrodes have good synchronism.In addition,the signal interference is less than 9.5%and decreases as the pressure decreases after the distance between adjacent sites exceeds 200μm.The integration of MTTS and signal processing units has potential applications in human-machine interaction systems,health status detection and smart assistive devices.

关键词： tactile/thermal sensor piezoelectric/pyroelectric effects high resolution spatial mapping motion monitoring

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子宫内膜癌诊疗已经进入分子时代

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中国妇产科临床杂志 2024年第2期25卷 97-98页

作者：李立伟王建六北京大学人民医院妇产科北京100044

子宫内膜癌(endometrial carcinoma,EC)是常见妇科恶性肿瘤,在组织学、遗传学和分子特征上均表现出高度异质性。2013年,癌症基因组图谱(TCGA)项目应用多组学平台分析数据库,将EC分为4种分子亚型:DNA聚合酶ε(DNA polymerase epsilon,PO... 详细信息

子宫内膜癌(endometrial carcinoma,EC)是常见妇科恶性肿瘤,在组织学、遗传学和分子特征上均表现出高度异质性。2013年,癌症基因组图谱(TCGA)项目应用多组学平台分析数据库,将EC分为4种分子亚型:DNA聚合酶ε(DNA polymerase epsilon,POLE)超突变型、高度微卫星不稳定性(microsatellite instability-high,MSI-H)型、低拷贝数型(copy-number low,CNL)和高拷贝数型(copy-number high,CNH)。20年来,国内外专家对EC的分子特征、分子分型进行临床转化研究,现已广泛深入应用于临床,并指导临床诊疗工作,可以说,EC的诊治已进入分子时代。

关键词：妇科恶性肿瘤子宫内膜癌分子亚型微卫星不稳定性分子特征 DNA聚合酶高拷贝数分子分型

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Dynamic analysis of the Wenchuan Earthquake disaster and reconstruction with 3-year remote sensing data

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International Journal of Digital Earth 2010年第4期3卷 355-364页

作者： Huadong Guo liangyun liu liping Lei Yanhong Wu liwei li Bing Zhang Zhengli Zuo Zhen li Key Laboratory of Digital Earth Science Center for Earth Observation and Digital EarthChinese Academy of SciencesBeijing 100190China

Earth observation is an effective technique that plays an important role in earthquake damage reduction and reconstruction.This paper introduces the results of dynamic analysis on monitoring and assessing heavily impacted areas affected by the Wenchuan Earthquake using remote sensing data acquired in the past 3 years from 2008 to 2010.Immediately after the disaster on 12 May 2008,the Chinese Academy of Sciences launched a project entitled‘Wenchuan Earthquake Disasters Monitoring and Assessment Using Remote Sensing Technology.’More than 400 images from 17 satellites and 20.2TB airborne remote sensing data were acquired to facilitate quick monitoring and evaluation of severely damaged areas in 14 counties.Results of the image analyses were forwarded on a timely basis to assist with consultative service and decisionmaking support.In subsequent years,in order to monitor the process of environmental restoration and reconstruction,airborne optical remote sensing images covering most of the severely damaged areas were again acquired in May 2009 and April 2010.These images were analyzed and compared along with images from 2008.Results were useful in support of further work on environmental protection and reconstruction in earthquake-damaged areas.Three typical areas were selected for illustrative purposes including Tangjiashan Barrier Lake,Beichuan County,and counties of Yingxiu and the new Beichuan.These results well demonstrate the importance and effectiveness of the utility of earth observation for disaster mitigation and reconstruction.

关键词： Wenchuan Earthquake earth observation disaster mitigation reconstruction

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近海风力发电用铜基粉末冶金摩擦材料研究进展

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材料导报 2024年第S1期38卷 348-353页

作者：刘晓旭李朝旭伦惠林蒋龙李立伟中国石油集团工程材料研究院有限公司油气钻采输送装备全国重点实验室西安710077 中国石油长庆油田公司气田开发事业部西安710018

近海风力发电机组制动具有“三高”(高速、高力矩、高压力)和“一特殊”(海洋水雾、盐雾腐蚀环境)的特点,铜基粉末冶金材料因具有组织均匀、导热性好、耐磨性高、摩擦系数稳定等优点,可应用于近海风力发电的摩擦材料。本文综述了近年来... 详细信息

近海风力发电机组制动具有“三高”(高速、高力矩、高压力)和“一特殊”(海洋水雾、盐雾腐蚀环境)的特点,铜基粉末冶金材料因具有组织均匀、导热性好、耐磨性高、摩擦系数稳定等优点,可应用于近海风力发电的摩擦材料。本文综述了近年来铜基粉末冶金摩擦材料在成分组元、制备工艺以及仿真模拟等方面的研究进展,其中铜基粉末冶金材料的成分组元主要包括基体组元、润滑组元和摩擦组元,其制备工艺主要采用传统热压烧结和放电等离子烧结,同时概述了材料在制动过程中温度场和应力场的仿真模拟,最后展望了铜基粉末冶金摩擦材料的发展前景。

关键词：近海风力发电铜基材料粉末冶金摩擦材料

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人工智能防御技术研究与启示

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现代防御技术 2024年第3期52卷 55-63页

作者：赵擎天李立伟陈鑫侯立志军事科学院系统工程研究院北京100101

人工智能技术在军事领域的广泛应用,催生战争形态不断演进。为应对智能化战争带来的挑战,通过分析人工智能技术发展趋势及其地位作用,讨论了在军事领域开展人工智能防御技术研究的必要性;从“硬打击”和“软打击”2个角度,给出了防御反... 详细信息

人工智能技术在军事领域的广泛应用,催生战争形态不断演进。为应对智能化战争带来的挑战,通过分析人工智能技术发展趋势及其地位作用,讨论了在军事领域开展人工智能防御技术研究的必要性;从“硬打击”和“软打击”2个角度,给出了防御反制人工智能武器系统的技术方法和AI安全防御架构;重点分析了污染打击、逆向打击、后门打击和对抗打击的技术原理;最后,从顶层设计、应用审查、数据治理、基础研究、指挥艺术和人机混合智能6个方面给出了加强人工智能防御技术研究的措施建议。

关键词：人工智能防御技术智能化战争机器学习硬打击软打击

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