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微波法合成香豆素-3-羧酸乙酯的工艺研究

化学世界 2011年第12期52卷 731-733页

作者：涂永元邱飞华侨大学分子药物学研究所福建泉州362021 分子药物教育部工程研究中心福建泉州362021

以水杨醛、丙二酸二乙酯为原料,二乙胺为催化剂,采用微波辐射技术合成香豆素-3-羧酸乙酯,利用正交实验设计考察了微波功率、原料配比、催化剂用量、辐射时间、溶剂用量对产物产率的影响。结果表明,当摩尔比水杨醛:丙二酸二乙酯:二乙胺=1... 详细信息

以水杨醛、丙二酸二乙酯为原料,二乙胺为催化剂,采用微波辐射技术合成香豆素-3-羧酸乙酯,利用正交实验设计考察了微波功率、原料配比、催化剂用量、辐射时间、溶剂用量对产物产率的影响。结果表明,当摩尔比水杨醛:丙二酸二乙酯:二乙胺=1:1.3:0.3时,5 mL乙醇,采用600 W微波辐射4 min,香豆素-3-羧酸乙酯产率可达88.8%。

关键词：香豆素-3-羧酸乙酯微波辐射正交设计

GC-MS法分析不同品牌藏香产品的化学成分

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云南民族大学学报（自然科学版） 2024年第5期33卷 562-569页

作者：涂永元国家燃香类产品质量检验检测中心(福建) 福建永春362600 永春县产品质量检验所福建永春362600 福建省香产品质量检验中心福建永春362600

为分析名优品牌藏香产品的化学成分及特征物质信息,以正己烷-丙酮混合溶液作为提取溶剂,对藏香样品进行超声提取,所得提取液经过滤后,再进样至气相色谱-质谱联用仪中分析并鉴定化学成分,通过峰面积归一化法获得各化合物相对百分含量.结... 详细信息

为分析名优品牌藏香产品的化学成分及特征物质信息,以正己烷-丙酮混合溶液作为提取溶剂,对藏香样品进行超声提取,所得提取液经过滤后,再进样至气相色谱-质谱联用仪中分析并鉴定化学成分,通过峰面积归一化法获得各化合物相对百分含量.结果表明,从A品牌藏香、B品牌藏香和C品牌藏香样品中分别鉴定出61、62和34种化合物,其中包括16种共有成分:雪松醇、异土木香内酯、土木香内酯、去氢木香内酯、表木栓醇、丁香酚、β-香树脂醇、24-norursa-3,12-dien-11-one、24-norursa-3,12-diene、无羁萜、α-香树脂醇、熊果醛、24-noroleana-3,12-diene、日柏酮、桉油烯醇、正二十九烷,上述共有成分平均相对含量依次为4.36%、4.35%、3.68%、3.19%、2.63%、2.43%、1.75%、1.53%、1.45%、1.31%、1.26%、0.90%、0.81%、0.59%、0.40%、0.33%,其中雪松醇是藏香样品中平均含量最高的化合物.另外,这些共有成分中有14种为萜类,且在上述3种样品中萜类总量占共有成分比例分别为93.29%、93.93%、86.66%,表明萜类成分是藏香共有成分中数量最多、相对含量占比最大的一类化合物.综上,通过GC-MS法获得藏香产品化学成分及其特征成分,可为后续藏香产品的进一步研究和开发提供科学依据和参考.

关键词：藏香燃香产品 GC-MS 成分分析

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气相色谱法测定藏香产品中8种成分的含量

化学工程师 2024年第2期38卷 18-23,50页

作者：涂永元国家燃香类产品质量检验检测中心(福建)永春县产品质量检验所福建省香产品质量检验中心福建泉州362600

建立了气相色谱法(Gas Chromatography with Flame Ionization Detector,GC-FID)测定藏香产品中樟脑、丁香酚、雪松醇、土木香内酯、异土木香内酯、去氢木香内酯、表木栓醇、木栓酮8种成分含量的方法。目标成分经正己烷-丙酮混合溶液超... 详细信息

建立了气相色谱法(Gas Chromatography with Flame Ionization Detector,GC-FID)测定藏香产品中樟脑、丁香酚、雪松醇、土木香内酯、异土木香内酯、去氢木香内酯、表木栓醇、木栓酮8种成分含量的方法。目标成分经正己烷-丙酮混合溶液超声提取,分别经气相色谱-质谱法定性、气相色谱法定量检测。考察并优化了提取溶剂种类、超声提取时间、温度等影响提取效率的各项参数。结果表明,8种成分在其浓度范围内线性相关系数良好,检出限在0.53~15.75μg·m L^(-1)之间,定量限在1.76~52.50μg·m L^(-1)之间;加标回收率为96.3%~107.5%,RSD为0.32%~5.2%,可满足实际分析要求。本方法操作简便、快速、重复性好,适用于藏香样品中特征成分的测定和快速分析。

关键词：藏香特征成分燃香含量

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Paget样鲍温病1例

中国皮肤性病学杂志 2017年第2期31卷 204-205页

作者：周培媚路永红涂媛章培成都市第二人民医院皮肤科四川成都610017 成都市第二人民医院病理科四川成都610017

患者女,78岁,右大腿暗红色斑片半年,偶尔痒痛。皮损组织病理示:表皮内查见Paget样细胞呈巢状排列,并有压迫、挤压邻近表皮细胞的倾向,免疫组化示CK5/6灶性阳性,CK7,GCDFP-15,CEA,HMB45阴性,诊断Paget样鲍温病。

关键词：鲍温病 Paget

Enhancing m^(6)A modification in the motor cortex facilitates corticospinal tract remodeling after spinal cord injury

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Neural Regeneration Research 2025年第6期20卷 1749-1763页

作者： Tian Qin Yuxin Jin Yiming Qin Feifei yuan Hongbin Lu Jianzhong Hu yong Cao Chengjun Li Department of Spine Surgery and Orthopedics Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Key Laboratory of Organ Injury Aging and Regenerative Medicine of Hunan ProvinceChangshaHunan ProvinceChina National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Department of Sports Medicine Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina

Spinal cord injury typically causes corticospinal tract disruption. Although the disrupted corticospinal tract can self-regenerate to a certain degree, the underlying mechanism of this process is still unclear. N6-methyladenosine(m^(6)A) modifications are the most common form of epigenetic regulation at the RNA level and play an essential role in biological processes. However, whether m^(6)A modifications participate in corticospinal tract regeneration after spinal cord injury remains unknown. We found that expression of methyltransferase 14 protein(METTL14) in the locomotor cortex was high after spinal cord injury and accompanied by elevated m^(6)A levels. Knockdown of Mettl14 in the locomotor cortex was not favorable for corticospinal tract regeneration and neurological recovery after spinal cord injury. Through bioinformatics analysis and methylated RNA immunoprecipitation-quantitative polymerase chain reaction, we found that METTL14 regulated Trib2 expression in an m^(6)A-regulated manner, thereby activating the mitogen-activated protein kinase pathway and promoting corticospinal tract regeneration. Finally, we administered syringin, a stabilizer of METTL14, using molecular docking. Results confirmed that syringin can promote corticospinal tract regeneration and facilitate neurological recovery by stabilizing METTL14. Findings from this study reveal that m^(6)A modification is involved in the regulation of corticospinal tract regeneration after spinal cord injury.

关键词： corticospinal tract remodeling epigenetic regulations locomotor cortex m^(6)A modification methyltransferase 14 protein(METTL14) mitogen-activated protein kinase neural regeneration spinal cord injury syringin TRIB2

Assessing the corrosion protection property of coatings loaded with corrosion inhibitors using the real-time atmospheric corrosion monitoring technique

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 119-126页

作者： Xiaoxue Wang Lulu Jin Jinke Wang Rongqiao Wang Xiuchun Liu Kai Gao Jingli Sun yong yuan Lingwei Ma Hongchang Qian Dawei Zhang School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beijing Institute of Space Long March Vehicle Beijing 100076China National Materials Corrosion and Protection Data Center University of Science and Technology BeijingBeijing 100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China Shanghai Spaceflight Precision Machinery Institute Shanghai 201600China

The atmospheric corrosion monitoring(ACM)technique has been widely employed to track the real-time corrosion behavior of metal ***,limited studies have applied ACM to the corrosion protection properties of organic *** study compared a bare epoxy coating with one containing zinc phosphate corrosion inhibitors,both applied on ACM sensors,to observe their corrosion protection properties over *** with artificial damage via scratches were exposed to immersion and alternating dry and wet environments,which allowed for monitoring galvanic corrosion currents in *** the corrosion tests,the ACM currents of the zinc phosphate/epoxy coating were considerably lower than those of the blank epoxy *** trend in ACM current variations closely matched the results obtained from regular electrochemical tests and surface *** alignment highlights the potential of the ACM technique in evaluating the corrosion protection capabilities of organic *** with the blank epoxy coating,the zinc phosphate/epoxy coating showed much-decreased ACM current values that confirmed the effective inhibition of zinc phosphate against steel corrosion beneath the damaged coating.

关键词： atmospheric corrosion monitoring technology corrosion inhibitor coating carbon steel corrosion protection

Multivariable sales prediction for filling stations via GA improved BiLSTM

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Petroleum Science 2022年第5期19卷 2483-2496页

作者： Shi-yuan Pan Qi Liao yong-tu Liang Beijing Key Laboratory of Urban Oil and Gas Distribution Technology China University of PetroleumBeijing102249China

Accurate sales prediction in filling stations is the basis to fill in the refined oil in time and avoid the outof-stock as much as *** the defect of great“lag”in the general time series model,this paper summarizes the multiple factors that influence the oil sales and develops a multivariable long short-term memory(LSTM)neural network,with the hyper-parameters being improved by the genetic algorithm(GA).To further improve the prediction accuracy,the proposed LSTM neural network is generalized to bidirectional LSTM(Bi LSTM),in which the impact of future factors on present sales can be taken into account by backward ***,different LSTM structures and genetic algorithm parameters are tested to discuss their impact on prediction *** demonstrated that genetic algorithm improved Bi LSTM model is superior to extreme gradient boosting,ARIMA,and artificial neural network,having the highest accuracy of 89%.

关键词： Refined oil Multivariable prediction BiLSTM Genetic algorithm Future influence

Co/Co_(7)Fe_(3)heterostructures with controllable alloying degree on carbon spheres as bifunctional electrocatalyst forrechargeable zinc-air batteries

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International Journal of Minerals,Metallurgy and Materials 2025年第2期32卷 476-487页

作者： Junkang Chen yongyue Zhuang Yanxin Qiao Yu Zhang Aihua yuan Hu Zhou School of Materials Science and Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China School of Environmental and Chemical Engineering Jiangsu University of Science and TechnologyZhenjiang 212003China

Exploring efficient and nonprecious metal electrocatalysts of oxygen reduction reaction(ORR)and oxygen evolution reaction(OER)is crucial for developing rechargeable zinc-air batteries(ZABs).Herein,an alloying-degree control strategy was employed to fabricate nitrogen-doped carbon sphere(NCS)decorated with dual-phase Co/Co_(7)Fe_(3)heterojunctions(CoFe@NCS).The phase composition of materials has been adjusted by controlling the alloying *** optimal CoFe_(0.08)@NCS electrocatalyst displays a half-wave potential of 0.80 V for ORR and an overpotential of 283 mV at 10 mA·cm^(-2)for OER in an alkaline *** intriguing bifunctional electrocatalytic activity and durability is attributed to the hierarchically porous structure and interfacial electron coupling of highly-active Co_(7)Fe_(3)alloy and metallic Co *** the CoFe_(0.08)@NCS material is used as air-cathode catalyst of rechargeable liquid-state zinc-air battery(ZAB),the device shows a high peak power-density(157 mW·cm^(-2))and maintains a stable voltage gap over 150 h,outperforming those of the benchmark(Pt/C+RuO_(2))-based *** particular,the as-fabricated solid-state flexible ZAB delivers a reliable compatibility under different bending *** work provides a promising strategy to develop metal/alloy-based electrocatalysts for the application in renewable energy conversion technologies.

关键词： bifunctional electrocatalysts oxygen reduction reaction oxygen evolution reaction zinc-air battery metal/alloy carbon sphere

3D Printing of Tough Hydrogel Scaffolds with Functional Surface Structures for Tissue Regeneration

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Nano-Micro Letters 2025年第2期17卷 18-45页

作者： Ke Yao Gaoying Hong Ximin yuan Weicheng Kong Pengcheng Xia yuanrong Li Yuewei Chen Nian Liu Jing He Jue Shi Zihe Hu Yanyan Zhou Zhijian Xie yong He State Key Laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Liangzhu Laboratory Zhejiang UniversityHangzhou 310027People’s Republic of China Key Laboratory of 3D Printing Process and Equipment of Zhejiang Province College of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Stomatology Hospital School of StomatologyZhejiang University School of MedicineHangzhou 310027People’s Republic of China State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001People’s Republic of China Institute of Digital Medicine Nanjing First HospitalNanjing Medical UniversityNanjing 210006People’s Republic of China

Hydrogel scaffolds have numerous potential applications in the tissue engineering ***,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical *** by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this ***,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent ***,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell ***,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT *** experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries.

关键词： 3D printing Tough hydrogel scaffold Functional surface structure Tissue regeneration Biomaterials