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原位溶胶-凝胶法制备光固化3D打印大豆油基杂化材料及其性能分析

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现代化工 2024年第S01期44卷 191-200页

作者：曹力铸李少辉刘晓暄崔艳艳广东工业大学材料与能源学院广东省功能软凝聚态物质重点实验室广东广州510006 化学与精细化工广东省实验室揭阳分中心广东揭阳522000

以2.7官能度大豆油多元醇(SBOP)与甲基丙烯酸乙酯二异氰酸酯(MOI)为原料,成功制备了2.7官能度可自由基光固化的大豆油基光敏树脂SBO-2.7A。将SBO-2.7A作为基体树脂,通过添加一定比例活性稀释剂丙烯酸羟乙酯(HEA),制备出了3D打印大豆油... 详细信息

以2.7官能度大豆油多元醇(SBOP)与甲基丙烯酸乙酯二异氰酸酯(MOI)为原料,成功制备了2.7官能度可自由基光固化的大豆油基光敏树脂SBO-2.7A。将SBO-2.7A作为基体树脂,通过添加一定比例活性稀释剂丙烯酸羟乙酯(HEA),制备出了3D打印大豆油基光敏树脂。通过原位溶胶-凝胶法,将不同正硅酸乙酯(TEOS)添加量的大豆油基打印树脂配方进行3D打印成型,优选出最佳的酸性蒸汽后处理条件后,最终制备出具有机械性能提高的打印大豆油基材料。通过红外光谱仪、电子显微镜、哈克旋转流变仪、拉伸试验机等对3D打印树脂的黏度、光固化行为及其对3D打印样品的热力学性能、机械性能等的影响进行分析,结果表明,原位溶胶-凝胶法生成纳米SiO2使得3D打印制品拉伸性能、储能模量均得到提高,其中拉伸强度由起始的9.96 MPa增加到了14.14 MPa,提高了42%;储能模量由293 MPa提高至567 MPa,提高了93.5%。

关键词：大豆油基光敏树脂 3D打印原位溶胶-凝胶法大豆油基杂化材料纳米二氧化硅

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龙脑精油化学成分与药理作用研究进展

中国中药杂志 2024年第11期49卷 2863-2870页

作者：黄思琪易畅刘晓轩杨皓宇张良琦唐宇张喜利刘文龙湖南中医药大学药学院湖南长沙410208 中药成药性与制剂制备湖南省重点实验室湖南长沙410208

龙脑樟是我国首次发现的富含右旋龙脑的樟树珍稀新品种,因其具有极高的利用价值,故又被称为植物黄金。龙脑精油是通过蒸馏等方式从龙脑樟的枝、叶、果实等部位提取得到的天然香气成分,主要含有单萜和倍半萜类化合物,具有镇痛、抗炎、抗... 详细信息

龙脑樟是我国首次发现的富含右旋龙脑的樟树珍稀新品种,因其具有极高的利用价值,故又被称为植物黄金。龙脑精油是通过蒸馏等方式从龙脑樟的枝、叶、果实等部位提取得到的天然香气成分,主要含有单萜和倍半萜类化合物,具有镇痛、抗炎、抗氧化、改善认知功能障碍、抑菌和杀虫等多种药理活性。作为龙脑生物医药工业产业中的高附加值产品,龙脑精油在医药领域、化工生产、食品工业等行业有很大的市场潜力。但目前关于其毒理学安全性评价资料尚不完善,其化学成分和药理作用也易受到产地、采收期、提取部位及前处理方法等多种因素的影响而存在差异,导致临床用药的安全性和疗效难以保障,这可能会对龙脑精油的合理有效利用造成一定阻碍。该文总结归纳了国内外相关文献,分析龙脑精油的发展现状,对其化学成分和药理作用进行综合概述,并进一步讨论当前研究存在的局限性和可能的解决方法,期望为龙脑精油的深度开发、临床应用提供参考,进一步推动以龙脑为核心的大健康产业链的形成与发展。

关键词：龙脑樟精油化学成分药理作用研究进展

基于HPLC检测市售博落回注射液中血根碱和白屈菜红碱的成分含量

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饲料研究 2024年第5期47卷 104-108页

作者：陈思雅张玮琛邱文艳刘晓轩杨晶湖南中医药大学药学院湖南长沙410208

试验旨在评估博落回注射剂产品的质量。试验采用高效液相色谱法,建立了博落回注射剂产品中血根碱和白屈菜红碱的同步测定方法。采用Agilent色谱柱,流动相为乙腈-0.1%磷酸,进行梯度洗脱,流速为1.0 mL/min,柱温30℃,检测波长为270 nm,进样... 详细信息

试验旨在评估博落回注射剂产品的质量。试验采用高效液相色谱法,建立了博落回注射剂产品中血根碱和白屈菜红碱的同步测定方法。采用Agilent色谱柱,流动相为乙腈-0.1%磷酸,进行梯度洗脱,流速为1.0 mL/min,柱温30℃,检测波长为270 nm,进样量5μL。结果显示,博落回注射液中血根碱和白屈菜红碱的HPLC测定方法专属性高,线性范围良好,重复性较好。血根碱和白屈菜红碱精密度RSD分别为0.45%、0.09%,稳定性的RSD分别为0.60%和0.39%,回收率范围分别为99.83%~101.79%、103.47%~105.56%。研究表明,该方法稳定可靠,具有较高的精密度和准确性,可用于评价市售博落回注射液的质量。

关键词：博落回注射液血根碱白屈菜红碱 HPLC 质量评价

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剪切波弹性成像评估妊娠期高血压合并胎儿颅内出血孕妇的胎盘功能

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湖北医药学院学报 2024年第3期43卷 295-299页

作者：刘晓萱汪晓祎刘文华胡培肖祖文郑光美湖北医药学院附属人民医院超声影像中心湖北十堰442000 湖北医药学院附属人民医院妇产中心湖北十堰442000

目的:探讨应用剪切波弹性成像技术(SWE)测量妊娠期高血压疾病(HDP)合并胎儿颅内出血(FICH)孕妇的胎盘杨氏模量值的变化,为临床早期诊断及干预提供帮助。方法:选取确诊HDP且胎盘为Ⅱ级的孕妇134例为病例组,根据是否合并FICH分为A组合并FI... 详细信息

目的:探讨应用剪切波弹性成像技术(SWE)测量妊娠期高血压疾病(HDP)合并胎儿颅内出血(FICH)孕妇的胎盘杨氏模量值的变化,为临床早期诊断及干预提供帮助。方法:选取确诊HDP且胎盘为Ⅱ级的孕妇134例为病例组,根据是否合并FICH分为A组合并FICH(28例)及B组非FICH(106例),并随机选取同期在我院正常妊娠且胎盘为Ⅱ级的129例孕妇作为对照组。所有孕妇均行SWE测量胎盘中央面及边缘面杨氏模量值,比较各组胎盘杨氏模量值的差异,绘制受试者工作特征曲线(ROC),评估胎盘杨氏模量值预测HDP及FICH的效能。结果:病例组胎盘中央面及边缘面杨氏模量值均明显高于对照组(P0.05);ROC曲线显示,病例组及A组胎盘中央区及边缘区杨氏模量值预测HDP的AUC为0.900、0.904及0.912、0.908。结论:SWE技术测量胎盘杨氏模量值在预测HDP疾病及合并FICH中有较高价值,可作为评估HDP患者胎盘功能的重要指标为临床诊断及治疗提供依据。HDP患者应常规检测胎盘杨氏模量值,进而预防胎儿缺氧、颅内出血等并发症的发生。

关键词：妊娠期高血压胎儿颅内出血剪切波弹性成像技术

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Vegetation changes in the agricultural-pastoral areas of northern China from 2001 to 2013

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Journal of Integrative Agriculture 2016年第5期15卷 1145-1156页

作者： SU Wei YU De-yong SUN Zhong-ping ZHAN Jun-ge liu xiao-xuan LUO Qian State Key Laboratory of Earth Surface Processes and Resource Ecology Beijing Normal University Beijing 100875 P.R. China State Key Laboratory of Remote Sensing Science/School of Geography Beijing Normal University Beijing 100875 P.R.China Satelfite Environment Center Ministry of Environmental Protection Beijing 100094 PR.China College of Information and Electrical Engineering China Agricultural University Beijing 100083 P.R.China

Climate change and human activity have resulted in increasing change of vegetation growth globally. Numerous studies have been conducted on extreme climate events and analyses of ecological environment evolution. However, such studies have placed little emphasis on vegetation change and spatial variation in this type of ecotone. Accordingly, this study analyzed the changes in vegetation type and growth using the 16-d composite MOD13A1 product with 1-km resolution and MOD12Q1 product with 1-km resolution. We used the mean, maximum, standard deviation normalized-difference vegetation index（NDVI） values, and the rate of change（ROC） of NDVI value to explain vegetation changes within the studied ecotone. Our results showed that significant vegetation type and growth changes have occurred in the study area. From 2001 to 2013, for example, with the exception of 2001, 2004 and 2009, a certain extent of grassland area was converted to cropland. Drought severity index（DSI） results indicate that there exists drought in 2001, 2004 and 2009. Such temporal changes in cropland and grassland area confirmed the ecological vulnerability of the ecotone. At the same time, vegetation varied spatially from west to east and from south to north. The mean, maximum and standard deviation NDVI values were all sorted in descending order based on differences in latitude and longitude, as follows： NDVI_（2013）〉NDVI_（2009）〉NDVI_（2004）〉NDVI_（2001）

关键词： vegetation growth agricultural-pastoral area MODIS land cover change temporal change spatial variation

Dynamic manipulation of multimodal emission in Er^(3+)-activated non-core-shell structure for optical thermometry and information security

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Rare Metals 2024年第4期43卷 1702-1712页

作者： xuan liu Zi-Xia Lin Yin-Biao Shi xiao-Yan Wang Ming-Ye Ding xiao-Fei Yang College of Science Nanjing Forestry UniversityNanjing210037China Testing Center Yangzhou UniversityYangzhou225009China

Regulating luminescent dynamics of lanthanide-based luminescent materials via external stimuli is of great significance in the fields of optical thermometry and high-level ***,it is still a huge challenge to realize multimodal emissions with tunable color outputs from a single activator in simple structures via smart dynamic control of photon transition ***,we present a mechanistic strategy to achieve multimodal luminescence of Er^(3+)activators with color-switchable outputs in a non-core-shell *** the control of excitation dynamics(λ_(ex)=980,808,1532,377 nm),the population among the intermediate en ergy levels of Er^(3+)and the interaction between Er^(3+)and Yb^(3+)could be precisely modulated through energy transfer and migration processes,leading to the generation of colortunable multimodal luminescence upon diverse excitation modes(non-steady-state,single-/dual-wavelength steady,thermal activation).Inspired by its special luminescent performance,the as-obtained material exhibits great potential in noncontact thermometry,multimodal anticounterfeiting,and high-capacity information encryption by performing a series of proof-of-concept *** findings might provide a conceptual model to modulate the luminescent dynamics in a simple-structured system for the generation of color-adjustable multimodal emissions,which is convenient for the development of advanced luminescent materials toward versatile cuttingedge applications.

关键词： Lanthanide ions Multimodal emission Upconversion Downshifting Anti-counterfeiting Luminescent thermometry

A metal-free coordination–insertion ring-opening polymerization of tetrahydrofuran by the central metalloid bis(pentafluorophenyl)(phenoxy)borane

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Chinese Chemical Letters 2024年第3期35卷 419-422页

作者： Cheng Wu Yixuan liu Chunsheng xiao Chenyang Hu xuan Pang Xuesi Chen Key Laboratory of Polymer Ecomaterials Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022China School of Applied Chemistry and Engineering University of Science and Technology of ChinaHefei 230026China

A new strategy for the metal-free coordination–insertion ring-opening polymerization of tetrahydrofuran by the central metalloid Boron has been first ***(pentafluorophenyl)(phenoxy)borane was used as a catalyst for the polymerization reaction *** polytetrahydrofuran with high molecular weight and narrow molecular weight distribution could be *** proposed mechanism was studied by MALDI-TOF,ESI-MS and O-18 isotope labeling analyses as a metal-free coordination insertion mechanism.

关键词： Metal-free catalyst Bis(pentafluorophenyl)(phenoxy)borane Coordination–insertion mechanism Ring-opening polymerization Polytetrahydrofuran

Corrosion behavior of Al_(2)O_(3)-C bricks in MnO-containing mold slag

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Journal of Iron and Steel Research International 2024年第6期31卷 1486-1492页

作者： Yi-jiang Zhao Guang-qiang Li Yang Wu Cheng Yuan Ze Meng xiao-xuan Deng Yu liu The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina Key Laboratory for Ferrous Metallurgy and Resources Utilization of Ministry of Education Wuhan University of Science and TechnologyWuhan 430081HubeiChina Hubei Provincial Key Laboratory for New Processes of Ironmaking and Steelmaking Wuhan University of Science and TechnologyWuhan 430081HubeiChina Research Institute of Technology Shougang Group Co.Ltd.Beijing 100043China

In order to explore the corrosion mechanism of Al_(2)O_(3)-C refractories in the mold flux bearing MnO,the immersion test of Al_(2)O_(3)-C refractories in CaO-SiO2-CaF2-MnO slag with different MnO contents was carried out at 1550℃.The results show that Mn particles were observed in the slag after experiment,due to the reduction of MnO by graphite in *** amounts of graphite were observed at the interface between refractories and slag,indicating that the oxidation of graphite is limited by the poor contact between graphite and molten ***,the oxidation of graphite is not the main cause of damage to refractories.A small quantity of CaO·2Al_(2)O_(3)(CA_(2))and CaO·6Al_(2)O_(3)(CA_(6))adjacent to Al_(2)O_(3) grain was detected at the slag/reaction layer ***_(2) and CA_(6) possess relatively high melting points,which is beneficial to hindering the further penetration of ***,the dissolution of Al_(2)O_(3) into slag is still the main cause for refractories *** increase in the MnO content of mold slag decreases the viscosity and then results in the severe corrosion of Al_(2)O_(3)-C bricks.

关键词： Al_(2)O_(3)-C refractory MnO-containing slag Graphite Corrosion

Smart materials for safe lithium-ion batteries against thermal runaway

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Journal of Energy Chemistry 2024年第7期94卷 360-392页

作者： Yu Ou Pan Zhou Wenhui Hou xiao Ma xuan Song Shuaishuai Yan Yang Lu Kai liu Department of Chemical Engineering Tsinghua UniversityBeijing 100084China

In recent years,the new energy storage system,such as lithium ion batteries(LIBs),has attracted much *** order to meet the demand of industrial progress for longer cycle life,higher energy density and cost efficiency,a quantity of research has been conducted on the commercial application of ***,it is difficult to achieve satisfying safety and cycling performance *** may be thermal runaway(TR),external impact,overcharge and overdischarge in the process of battery abuse,which makes the safety problem of LIBs more *** this review,we summarize recent progress in the smart safety materials design towards the goal of preventing TR of LIBs reversibly from different abuse *** from smart responsive materials and novel structural design,the safety of LIBs can be improved a *** expect to provide a comprehensive reference for the development of smart and safe lithium-based battery materials.

关键词： Lithium ion batteries(LIBs) Thermal runaway(TR) Smart materials Safe batteries Solid electrolyte interface(SEI)