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Partial oxidation of methane by photocatalysis

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Chinese Chemical Letters 2024年第1期35卷 153-168页

作者： Zhongshan Yang Qiqi Zhang Hui Song Xin Chen Jiwei Cui yanhui sun Lequan Liu Jinhua Ye TJU-NIMS International Collaboration Laboratory School of Materials Science and EngineeringTianjin UniversityTianjin 300072China International Center for Materials Nanoarchitectonics(WPI-MANA) National Institute for Materials Science(NIMS)1-1 NamikiIbaraki 3050047Japan Zhejiang LAMP Co. Ltd.Wenzhou 325206China

Methane chemistry is one of the“Holy Grails of catalysis”.It is highly desirable but challenge to transform methane into value-added chemicals,because of its high C-H bonding energy(435 kJ/mol),lack ofπbonding or unpaired electrons.Currently,commercial methane conversion is usually carried out in harsh conditions with enormous energy input.Photocatalytic partial oxidation of methane to liquid oxygenates(PPOMO)is a future-oriented technology towards realizing high efficiency and high selectivity under mild conditions.The selection of oxidant is crucial to the PPOMO performance.Hence,attentions are paid to the research progress of PPOMO with various oxidants(O_(2),H_(2)O,H_(2)O_(2)and other oxidants).Moreover,the activation of the selected oxidants is also highly emphasized.Meanwhile,we summarized the methane activation mechanisms focusing on the C-H bond that was broken mainly by·OH radical,O-specie or photogenerated hole(h+).Finally,the challenges and prospects in this subject are briefly discussed.

关键词： Partial oxidation of methane Photocatalysis Liquid oxygenates Oxidants C-H activation

Theoretical insights into the degradation mechanisms, kinetics and eco-toxicity of oxcarbazepine initiated by OH radicals in aqueous environments

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Journal of Environmental Sciences 2023年第7期129卷 189-201页

作者： yanhui sun Ming Li Mohammad Hassan Hadizadeh Lin Liu Fei Xu College of Environment and Safety Engineering Qingdao University of Science and TechnologyQingdao 266042China Environment Research Institute Shandong UniversityQingdao 266237China

As an anticonvulsant,oxcarbazepine(OXC)has attracted considerable attention for its potential threat to aquatic organisms.Density functional theory has been used to study the mechanisms and kinetics of OXC degradation initiated by OH radicals in aqueous environment.A total of fourteen OH-addition pathways were investigated,and the addition to the C8 position of the right benzene ringwas themost vulnerable pathway,resulting in the intermediate IM8.The H-abstraction reactions initiated by OH radicalswere also explored,where the extraction site of the methylene group(C14)on the seven-member carbon heterocyclic ring was found to be the optimal path.The calculations show that the total rate constant of OXC with OH radicals is 9.47×10^(9)(mol/L)^(−1)sec^(−1),and the half-life time is 7.32 s at 298 K with the[·OH]of 10^(−11) mol/L.Moreover,the branch ratio values revealed that OH-addition(89.58%)shows more advantageous than H-abstraction(10.42%).To further understand the potential eco-toxicity of OXC and its transformation products to aquatic organisms,acute toxicity and chronic toxicity were evaluated using ECOSAR software.The toxicity assessment revealed that most degradation products such as OXC-2OH,OXC-4OH,OXC-1O-1OOH,and OXC-1OH’are innoxious to fish and daphnia.Conversely,green algae are more sensitive to these compounds.This study can provide an extensive investigation into the degradation of OXC by OH radicals and enrich the understanding of the aquatic oxidation processes of pharmaceuticals and personal care products(PPCPs).

关键词： Oxcarbazepine OH radicals Degradation mechanisms Kinetic calculation Eco-toxicity evaluation

Fast electrochemical activation of the broadband saturable absorption of tungsten oxide nanoporous film

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Nano Research 2022年第1期15卷 326-332页

作者： Ruipeng Hou Hui Li Mengjuan Diao yanhui sun Ying Liang Zhiyang Yu Zhipeng Huang Chi Zhang School of Chemical Science and Engineering Tongji UniversityShanghai 200092China State Key Laboratory of Photocatalysis on Energy and Environment College of ChemistryFuzhou UniversityFuzhou 350002China

The on-demand modulation of defects in materials for the effective modulation of optical nonlinearity is desirable,while it remains a great challenge.In this work,we demonstrate that electrochemical activation is a facile and convenient approach to modulating the broadband third-order nonlinear absorption of nanoporous tungsten oxide(WO3-x)thin film.The film does not exhibit optical nonlinearity at the initial state,while shows a distinct saturable absorption under an applied voltage of-2.5 V with the excitation of 515,800,and 1,030 nm laser.The nonlinear absorption coefficient(β_(eff))is-766.38±6.67 cm·GW^(-1) for 1,030 nm laser,-624.24±17.15 cm·GW-1 for 800 nm laser,and-120.70±11.49 cm·GW^(-1) for 515 nm laser,and the performance is competitive among inorganic saturable absorbers.The activation is accomplished in 2 min.The performance enhancement is ascribed to the formation of abundant in-gap defect states because of the reduction of the tungsten atoms,and a Pauli-blocking effect occurs during the excitation of in-gap defect states.The small feature size of WO_(3-x)(-12 nm)enables the effective and fast introduction and removal of the defects in porous film,and accordingly the fast and broadband modulation of optical nonlinearity.Our results suggest a controllable,effective,and convenient approach to tuning the nonlinear absorption of materials.

关键词： tungsten oxide nonlinear absorption in-gap states electrochemical activation

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浸入式水口对薄板坯结晶器内钢液流动的影响

钢铁研究学报 2024年第1期36卷 66-75页

作者：李瑜孙彦辉宋思程王超北京科技大学钢铁共性技术协同创新中心北京100083 一重集团大连工程技术有限公司辽宁大连116000

为适应某钢厂新的生产线,提高其连铸连轧效率,重点探究、揭示了浸入式水口开口个数对薄板坯结晶器内冶金行为的影响规律。研究采用有限元软件ANSYS Fluent,针对高拉速(5m/min)薄板坯漏斗型结晶器在不同水口结构下的流动和传热行为进行... 详细信息

为适应某钢厂新的生产线,提高其连铸连轧效率,重点探究、揭示了浸入式水口开口个数对薄板坯结晶器内冶金行为的影响规律。研究采用有限元软件ANSYS Fluent,针对高拉速(5m/min)薄板坯漏斗型结晶器在不同水口结构下的流动和传热行为进行三维数值模拟仿真,并分析比较模拟结果,结合液面波动指数F数,择出最优的水口。结果表明:在流场分析中,两孔水口弯月面处的最大流速为0.709m/s,三孔水口和四孔水口最大流速相近,分别为0.575、0.578m/s,两孔水口对自由液面造成的扰动更大;在温度场分析中,两孔水口顶面温度范围整体较高,温度最大值出现在窄壁处;三孔和四孔水口顶面最大温度均1810K以下,且三孔水口高温区域较大,有利于保护渣的熔化。计算F数可得F_(2)为4.09、F_(3)为2.65、F_(4)为2.88。三孔水口F3数值最小(F_(3)

关键词：薄板坯高拉速漏斗型结晶器数值模拟液面波动指数

A novel mitochondria-targeting tetrapeptide for subcellular delivery of nanoparticles

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Chinese Chemical Letters 2019年第7期30卷 1435-1439页

作者： yanhui sun Aiyan Zhan Shuang Zhou Xiao Kuang Hongyan Shen Hongzhuo Liu Youjun Xu School of Pharmaceutial Engineering Key Laboratory of Structure-Based Drug Design & Discovery(Ministry of Education) Shenyang Pharmaceutical University Shenyang 110016 China Wuya College of Innovation Shenyang Pharmaceutical University Shenyang 110016 China

Mitochondrial dysfunction is associated with the emergence of several neurological and cardiovascular diseases. Hence, mitochondria-targeting delivery strategies are highly significant and critically needed. In this study, we developed a small library of peptides simulating the mitochondria-targeting peptide SS-31, a promising tetra-peptide with antioxidant character, and subsequently evaluated the toxicity, antioxidant ability and mitochondrial delivery of nanoparticles. Among the designed peptides, RF-2 (DArg-Dmt-Arg-Phe-NH2) showed controlled toxicity and excellent protection against gentamicin-induced hair cell damage, as compared with SS-31. More importantly, RF-2-modified PLGA nanoparticles demonstrated high colocalization with mitochondria and comparable specific subcellular accumulation, when compared with SS-31. Taken together, the obtained results supported RF-2 as a mitochondriatargeting peptide with high potential as a targeted carrier.

关键词： Mitochondrial targeting Peptide SS-31 Toxicity Nanoparticles Zebrafish

古尔班通古特沙漠东南部不同类型沙丘土壤水分与地形-植被因子关系

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水土保持研究 2024年第1期31卷 70-78页

作者：孙琰蕙张定海吴贤忠张艳灵甘肃农业大学理学院数量生物研究所兰州730070 兰州城市学院城市环境学院兰州730070

[目的]揭示古尔班通古特沙漠土壤水分的分布规律及其与地形—植被因子的关系,对制定相应的防风固沙措施以及建立科学合理的植物固沙模式有积极的指导作用。[方法]以古尔班通古特沙漠东南部地区3种不同类型沙丘(固定、半固定和流动沙丘)... 详细信息

[目的]揭示古尔班通古特沙漠土壤水分的分布规律及其与地形—植被因子的关系,对制定相应的防风固沙措施以及建立科学合理的植物固沙模式有积极的指导作用。[方法]以古尔班通古特沙漠东南部地区3种不同类型沙丘(固定、半固定和流动沙丘)为研究对象,利用方差分析和冗余分析等方法对3种不同类型沙丘上4种微地貌类型(迎风坡、背风坡、丘顶、丘底)不同深度土壤水分(0—40 cm, 40—200 cm, 200—300 cm)分布特征及其与地形—植被因子之间的关系进行综合分析。[结果](1)所有类型沙丘上0—300 cm土壤水分的波动程度随深度的增加逐渐减小,表层土壤水分的波动程度大于中层和深层。(2)所有类型沙丘不同深度的土壤水分有显著的差异,且背风坡、丘底和迎风坡3种微地貌类型上土壤水分相对较为集中。(3)地形—植被因子对研究区绝大多数(半)固定沙丘的土壤水分呈负相关关系,对(半)固定沙丘不同深度土壤水分影响较流动沙丘更为明显。[结论]所有类型沙丘上的土壤水分受地形因子的影响较植被因子强,而且影响不同类型沙丘土壤水分的主要地形—植被因子也不同。

关键词：土壤水分影响因子冗余分析古尔班通古特沙漠

Fast Evaluation Peanut Oil Quality by Synchronous Fluorescence Spectroscopy and Statistical Analysis

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Agricultural Sciences 2021年第5期12卷 565-574页

作者： Weiwei Zhang Riqin Lv yanhui sun Haiyang Gu School of Biotechnology and Food Engineering Chuzhou University Chuzhou China

Peanut oil oxidation was to monitor and quantify combining synchronous fluorescence spectroscopy and chemometrics. Peanut oil was subjected to an accelerated oxidation testing. The spectral and related chemical indicators were caught during oxidation induce testing. Fluorescence spectra were gained for each sample with simultaneous excitation from 200 to 800 nm and the offsets (Δλ) of 10 to 180 nm during the oxidation process. The results showed the induce period (IP) of the peanut oil was 16.45 h. Parallel factor analysis (PARAFAC) was performed to select the best Δλ interval of 70 nm, which spectral data was the most suitable for interval partial least square (iPLS) and synergy interval PLS (siPLS) modeling and forecast. The study presented all interval selection methods had the better results than the global spectrum modelling. iPLS reached the best into 10 intervals with a ratio of prediction to deviation (RPD) of 2.10. siPLS that separated the whole spectrum into 15 intervals and combined the third intervals (282 to 320 nm, 362 to 400 nm, and 761 to 800 nm) had a ratio of RPD of 2.26. The results showed the optimal siPLS model performed a little better than iPLS. The established model lying on interval selection could improve the prediction accuracy. It could provide a quick, accurate method to monitor oil oxidation process.

关键词： Synchronous Fluorescence Spectroscopy Peanut Oil Oxidation Stability Chemometrics

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四流大圆坯中间包挡墙优化

连铸 2024年第1期 32-37,45页

作者：江野李明吴建永毛乃旭宋思程孙彦辉南京钢铁股份有限公司特钢事业部江苏南京210044 北京科技大学钢铁共性技术协同创新中心北京100083

为了解决某钢厂在生产条件欠佳时中间两流的铸坯质量明显低于边部两流的问题,提高中间包的各流一致性及减少中间包的死区比例,在同一个挡墙上设计了3种开孔方式,并通过水模型物理试验获得了各方案的时间停留分布(RTD)曲线。经过分析RTD... 详细信息

为了解决某钢厂在生产条件欠佳时中间两流的铸坯质量明显低于边部两流的问题,提高中间包的各流一致性及减少中间包的死区比例,在同一个挡墙上设计了3种开孔方式,并通过水模型物理试验获得了各方案的时间停留分布(RTD)曲线。经过分析RTD曲线获得了各方案对应的死区、活塞流区及全混流区比例。同时综合考虑RTD曲线的尖峰和各流间的一致性,获得了最优的生产方案。研究结果表明,侧边单孔的方案B1流场最优,其孔径为140 mm,竖直角度为20°。其两流流动一致性很好,死区比例为19.95%,且RTD曲线无尖峰及双峰。

关键词：中间包结构优化挡墙死区比例 RTD曲线

核受体FXR调控内质网应激途径缓解小鼠溃疡性结肠炎病理损伤

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胃肠病学和肝病学杂志 2024年第1期33卷 48-54页

作者：热依拉·加帕尔郭沁伊尔潘·库尔班孙燕辉新疆维吾尔自治区第三人民医院消化内科新疆乌鲁木齐830099

目的探究法尼醇X受体(farnesoid X receptor,FXR)激活对溃疡性结肠炎(ulcerative colitis,UC)模型小鼠结肠组织病理损伤的影响及其作用机制。方法将40只C57BL/6雄性健康小鼠随机分为对照组、模型组、奥贝胆酸(obeticholic acid,OCA)... 详细信息

目的探究法尼醇X受体(farnesoid X receptor,FXR)激活对溃疡性结肠炎(ulcerative colitis,UC)模型小鼠结肠组织病理损伤的影响及其作用机制。方法将40只C57BL/6雄性健康小鼠随机分为对照组、模型组、奥贝胆酸(obeticholic acid,OCA)组、奥贝胆酸+衣霉素(OCA+TM)组,记录各组小鼠体质量、粪便性状与隐血程度、疾病活动指数(disease activity index,DAI)、剥离结肠长度。ELISA法检测各组小鼠血清IL-1β、IL-6、TNF-α含量,HE染色观察各组小鼠结肠组织病理形态变化,免疫组化染色检测各组小鼠结肠组织中GRP78和CCAAT/CHOP阳性表达情况,RT-qPCR和Western blotting检测各组小鼠结肠组织中GRP78和CHOP在mRNA与蛋白水平上的表达变化。结果与对照组比较,模型组小鼠DAI升高,结肠长度缩短,血清中IL-1β、IL-6、TNF-α含量均增加,结肠组织发生明显损伤,可见广泛炎性细胞浸润,结肠组织中GRP78和CHOP阳性染色增强,GRP78和CHOP的mRNA相对表达量和蛋白相对表达量均上调(P<0.05);与模型组比较,OCA组小鼠DAI降低,结肠长度增加,血清中IL-1β、IL-6、TNF-α含量均减少,结肠组织损伤程度明显改善,未见炎性细胞浸润,结肠组织中GRP78和CHOP阳性染色减弱,且GRP78和CHOP的mRNA相对表达量与蛋白相对表达量均下调(P<0.05);而与OCA组比较,OCA+TM组小鼠DAI升高而结肠长度缩短,血清中IL-1β、IL-6、TNF-α含量也均增加,结肠组织损伤,表现出明显的溃疡现象,同时,结肠组织中GRP78和CHOP阳性染色增强,GRP78和CHOP的mRNA相对表达量与蛋白相对表达量也均上调(P<0.05)。结论在UC小鼠模型中激活FXR能够有效缓解结肠组织病理损伤,该机制可能与调控内质网应激途径有关。

关键词：溃疡性结肠炎法尼醇X受体奥贝胆酸内质网应激