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Experimental Study on Geometry Characteristics of Turbulent Premixed Flames for Natural Gas/Air Mixtures

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Journal of Thermal Science 2025年第1期34卷 268-282页

作者： ZHENG Weilin WANG Qijiao xiao Huahua CHEN xiaoxiao XIE Fan ZENG Wen Liaoning Key Lab of Advanced Test Technology for Aerospace Propulsion System Shenyang Aerospace University State Key Laboratory of Fire Science University of science and Technology of China AVIC Shenyang Aircraft Design and Research Institute

In this study,focusing on the geometry characteristics of spherical expanding flame,the turbulent premixed flames of natural gas/air mixtures were investigated in a fan-stirred turbulent *** effects of initial temperature（T=300-400 K）,initial pressure（P=0.1-0.3 MPa）,turbulence intensity（u'=1.0-2.7 m/s）,oxygen volumetric percentage(φ（O2）=15%-21%) and carbon dioxide volumetric percentage(φ（CO2）=0-20%)were delved *** flame profile under the Cartesian coordinate system was derived from the schlieren images taken by the high-speed ***,from both macroscopic and microscopic perspectives,the influence of experimental conditions on the flame geometry characteristics was explored through flame front extraction,wavelet decomposition and network *** results demonstrate that for significant flame wrinkling,changes in species concentrations and turbulence intensity have more pronounced effects on the flame wrinkling *** wrinkling of the flame front maintains a certain degree of similarity,as evidenced by the locally concentrated distribution of the angles of the maximum fluctuation *** disturbance energy under large-scale（D6-D8） disturbances exhibits relatively high values with a similar trend,exerting a significant impact on the geometry characteristics of the flame *** peaks of correlation degree are scattered either with the decomposition scale or the development of flame radius,indicating no linear correlation between different detail ***,the probability distribution of node degrees in key wrinkled regions exhibits different trends with that of large-scale wrinkling and disturbance energy,especially with changes in initial *** occurs because the number of key wrinkles varies based on the perturbation's strength or the region's ***,an increase in the fluctuation frequency of the flame's local radius may not necessarily lead to an increase in the number of key folded regions.

关键词： fan-stirred turbulent combustor geometry characteristics large-scale wrinkling network topology wavelet decomposition

Photoinduced radical sulfur dioxide insertion with asymmetric cyclization of alkenes: accessing β-chiral sulfones bearing S-stereocentric cyclic sulfinamides

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Science China Chemistry 2025年第1期68卷 257-263页

作者： Jiapian Huang Chenxin Wang Xu Wang xiaoyu Zhou Wei xiao Jie Wu School of Pharmaceutical and Chemical Engineering & Institute for Advanced Studies Taizhou University State Key Laboratory of Organometallic Chemistry Shanghai Institute of Organic Chemistry Chinese Academy of Sciences School of Chemistry and Chemical Engineering Henan Normal University

The generation of various β-chiral sulfones bearing chiral cyclic sulfinamides through photoredox-catalyzed sulfur dioxide insertion with asymmetric radical cyclization is described. This method features a broad substrate scope and excellent stereospecificity. Computational studies reveal that the dispersion interaction between sulfinyl group and CH2SO2Ph group plays a crucial role in the stereoselectivity control.

关键词： β-chiral sulfones chiral cyclic sulfinamides sulfur dioxide insertion asymmetric radical cyclization stereoselectivity

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重组α-L-鼠李糖苷酶制备普鲁宁

中国现代应用药学 2016年第8期33卷 1025-1030页

作者：陈俊李利君倪辉肖安风华侨大学化工学院福建厦门361021 集美大学食品与生物工程学院福建厦门361021

目的利用重组α-L-鼠李糖苷酶,以柚皮苷为底物,通过生物转化法制备普鲁宁。方法以HPLC检测生物转化反应产物,通过DNS法对酶促反应过程进行动态分析,分析酶促反应动力学,优化普鲁宁制备工艺。结果重组α-L-鼠李糖苷酶水解柚皮苷反应完全... 详细信息

目的利用重组α-L-鼠李糖苷酶,以柚皮苷为底物,通过生物转化法制备普鲁宁。方法以HPLC检测生物转化反应产物,通过DNS法对酶促反应过程进行动态分析,分析酶促反应动力学,优化普鲁宁制备工艺。结果重组α-L-鼠李糖苷酶水解柚皮苷反应完全后,可得到反应产物普鲁宁和鼠李糖;生物转化法制备普鲁宁的最适反应温度为60℃、p H值为4.0、加酶量为12 U·m L?1、底物浓度为2.0 g·L?1,在此最优工艺条件下,94%的柚皮苷转化为普鲁宁;高浓度的Mn2+、Fe2+能够促进柚皮苷转化生成普鲁宁;重组酶对底物亲和力强,酶促反应的米氏常数Km为1.02μmol·m L?1,Vmax为0.19μmol·m L?1·min?1。结论利用重组α-L-鼠李糖苷酶生物转化法制备普鲁宁,转化率高、重现性好、产物易于分离,可为普鲁宁功能研究、开发利用及改性等提供重要依据。

关键词：重组α-L-鼠李糖苷酶柚皮苷普鲁宁生物转化

miRNA-21-5p is an important contributor to the promotion of injured peripheral nerve regeneration using hypoxia-pretreated bone marrow-derived neural crest cells

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Neural Regeneration Research 2025年第1期20卷 277-290页

作者： Meng Cong Jing-Jing Hu Yan Yu xiao-Li Li xiao-Ting Sun Li-Ting Wang Xia Wu Ling-Jie Zhu xiao-Jia Yang Qian-Ru He Fei Ding Hai-Yan Shi School of Medicine Nantong UniversityNantongJiangsu ProvinceChina Key Laboratory of Neuroregeneration of Jiangsu and Ministry of Education and Coinnovation Center of Neuroregeneration Nantong UniversityNantongJiangsu ProvinceChina Department of Physiology Jiangsu Health Vocational CollegeNanjingJiangsu ProvinceChina Department of Pathology Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina Jiangsu Clinical Medicine Center of Tissue Engineering and Nerve Injury Repair Affiliated Hospital of Nantong UniversityNantongJiangsu ProvinceChina

Our previous study found that rat bone marrow–derived neural crest cells(acting as Schwann cell progenitors)have the potential to promote long-distance nerve ***-based therapy can enhance peripheral nerve repair and regeneration through paracrine bioactive factors and intercellular ***,the complex contributions of various types of soluble cytokines and extracellular vesicle cargos to the secretome remain *** investigate the role of the secretome and extracellular vesicles in repairing damaged peripheral nerves,we collected conditioned culture medium from hypoxia-pretreated neural crest cells,and found that it significantly promoted the repair of sensory neurons damaged by oxygen-glucose *** mRNA expression of trophic factors was highly expressed in hypoxia-pretreated neural crest *** performed RNA sequencing and bioinformatics analysis and found that miR-21-5p was enriched in hypoxia-pretreated extracellular vesicles of neural crest ***,to further clarify the role of hypoxia-pretreated neural crest cell extracellular vesicles rich in miR-21-5p in axonal growth and regeneration of sensory neurons,we used a microfluidic axonal dissociation model of sensory neurons in vitro,and found that hypoxia-pretreated neural crest cell extracellular vesicles promoted axonal growth and regeneration of sensory neurons,which was greatly dependent on loaded ***,we constructed a miR-21-5p-loaded neural conduit to repair the sciatic nerve defect in rats and found that the motor and sensory functions of injured rat hind limb,as well as muscle tissue morphology of the hind limbs,were obviously *** findings suggest that hypoxia-pretreated neural crest extracellular vesicles are natural nanoparticles rich in ***-21-5p is one of the main contributors to promoting nerve regeneration by the neural crest cell *** helps to explain the mechanism of action of the secretome and e

关键词： axotomy cell-free therapy conditioned medium extracellular vesicles hypoxic preconditioning microRNA oxygen-glucose deprivation peripheral nerve injury Schwann cell precursors

COMPrompter: reconceptualized segment anything model with multiprompt network for camouflaged object detection

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Science China(Information Sciences) 2025年第1期68卷 189-203页

作者： xiaoqin ZHANG Zhenni YU Li ZHAO Deng-Ping FAN Guobao xiao Zhejiang Province Key Laboratory of Intelligent Informatics for Safety and Emergency Wenzhou University Nankai International Advanced Research Institute (SHENZHEN FUTIAN) College of Computer Science Nankai University School of Computer Science and Technology Tongji University

We rethink the segment anything model(SAM) and propose a novel multiprompt network called COMPrompter for camouflaged object detection(COD). SAM has zero-shot generalization ability beyond other models and can provide an ideal framework for COD. Our network aims to enhance the single prompt strategy in SAM to a multiprompt strategy. To achieve this, we propose an edge gradient extraction module, which generates a mask containing gradient information regarding the boundaries of camouflaged objects. This gradient mask is then used as a novel boundary prompt, enhancing the segmentation process. Thereafter, we design a box-boundary mutual guidance module, which fosters more precise and comprehensive feature extraction via mutual guidance between a boundary prompt and a box prompt. This collaboration enhances the model's ability to accurately detect camouflaged objects. Moreover, we employ the discrete wavelet transform to extract high-frequency features from image embeddings. The high-frequency features serve as a supplementary component to the multiprompt ***, our COMPrompter guides the network to achieve enhanced segmentation results, thereby advancing the development of SAM in terms of COD. Experimental results across COD benchmarks demonstrate that COMPrompter achieves a cutting-edge performance, surpassing the current leading model by an average positive metric of 2.2% in COD10K. In the specific application of COD, the experimental results in polyp segmentation show that our model is superior to top-tier methods as well. The code will be made available at https://***/guobaoxiao/COMPrompter.

关键词： segment anything model camouflaged object detection boundary prompt

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柚皮中柚皮苷和类柠檬苦素的提取及分离纯化

集美大学学报（自然科学版） 2015年第6期20卷 414-420页

作者：杨秋明李靖雅肖安风陈俊集美大学食品与生物工程学院福建厦门361021 福建省食品微生物与酶工程重点实验室福建厦门361021 厦门市食品生物工程技术研究中心福建厦门361021 厦门南方海洋研究中心经济海藻资源化利用与深加工重点实验室福建厦门361021

用热水煮提法提取出柚皮中柚皮苷和类柠檬苦素等大量苦味活性物质,通过静态吸附-解吸试验,筛选出具有较大吸附和解吸率的D101大孔吸附树脂进行分离纯化,得出最优的吸附条件:树脂添加量3.0%(质量分数),25℃恒温条件下摇床以180 r/min振荡... 详细信息

用热水煮提法提取出柚皮中柚皮苷和类柠檬苦素等大量苦味活性物质,通过静态吸附-解吸试验,筛选出具有较大吸附和解吸率的D101大孔吸附树脂进行分离纯化,得出最优的吸附条件:树脂添加量3.0%(质量分数),25℃恒温条件下摇床以180 r/min振荡90 min.在此条件下,柚皮苷和柠檬苦素吸附率都达到100%.吸附完全后进行动态洗脱,洗脱液再通过萃取和重结晶后可有效分离纯化柚皮苷和柠檬苦素类似物,纯化后的样品用HPLC法测得柚皮苷纯度达到95.8%,用紫外分光光度法测得柠檬苦素类似物纯度达到90.9%.

关键词：柚皮苷柠檬苦素类似物大孔吸附树脂分离纯化

Endoplasmic reticulum stress and autophagy in cerebral ischemia/reperfusion injury:PERK as a potential target for intervention

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Neural Regeneration Research 2025年第5期20卷 1455-1466页

作者： Ju Zheng Yixin Li Ting Zhang Yanlin Fu Peiyan Long xiao Gao Zhengwei Wang Zhizhong Guan xiaolan Qi Wei Hong Yan xiao Key Laboratory of Endemic and Ethnic Diseases Ministry of Education&Key Laboratory of Medical Molecular Biology of Guizhou ProvinceGuizhou Medical UniversityGuiyangGuizhou ProvinceChina Guizhou Center for Disease Control and Prevention GuiyangGuizhou ProvinceChina Department of Histology and Embryology Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Collaborative Innovation Center for Prevention and Control of Endemic and Ethnic Regional Diseases Co-constructed by the Province and Ministry GuiyangGuizhou ProvinceChina

Several studies have shown that activation of unfolded protein response and endoplasmic reticulum(ER)stress plays a crucial role in severe cerebral ischemia/reperfusion *** occurs within hours after cerebral ischemia,but the relationship between ER stress and autophagy remains *** this study,we established experimental models using oxygen-glucose deprivation/reoxygenation in PC12 cells and primary neurons to simulate cerebral ischemia/reperfusion *** found that prolongation of oxygen-glucose deprivation activated the ER stress pathway protein kinase-like endoplasmic reticulum kinase(PERK)/eukaryotic translation initiation factor 2 subunit alpha(e IF2α)-activating transcription factor 4(ATF4)-C/EBP homologous protein(CHOP),increased neuronal apoptosis,and induced ***,inhibition of ER stress using inhibitors or by si RNA knockdown of the PERK gene significantly attenuated excessive autophagy and neuronal apoptosis,indicating an interaction between autophagy and ER stress and suggesting PERK as an essential target for regulating *** autophagy with chloroquine exacerbated ER stress-induced apoptosis,indicating that normal levels of autophagy play a protective role in neuronal injury following cerebral ischemia/reperfusion *** from this study indicate that cerebral ischemia/reperfusion injury can trigger neuronal ER stress and promote autophagy,and suggest that PERK is a possible target for inhibiting excessive autophagy in cerebral ischemia/reperfusion injury.

关键词： apoptosis ATF4 autophagy C/EBP homologous protein cerebral ischemia/reperfusion injury eIF2α endoplasmic reticulum stress PERK

黑曲霉DB056发酵α-鼠李糖苷酶和柚苷酶培养基的优化研究

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中国食品学报 2010年第4期10卷 193-201页

作者：吴升山蔡慧农苏文金倪辉李利君肖安风集美大学生物工程学院福建厦门361021 厦门市食品生物工程技术研究中心福建厦门361021

目的:优化黑曲霉DB056产α-鼠李糖苷酶和柚苷酶的培养基,提高这两种酶的产量。方法:以α-鼠李糖苷酶活力和柚苷酶活力为指标,研究碳源、氮源和乳化剂TritonX-100对α-鼠李糖苷酶活力和柚苷酶活力的影响,优化黑曲霉DB056摇瓶发酵α-鼠李... 详细信息

目的:优化黑曲霉DB056产α-鼠李糖苷酶和柚苷酶的培养基,提高这两种酶的产量。方法:以α-鼠李糖苷酶活力和柚苷酶活力为指标,研究碳源、氮源和乳化剂TritonX-100对α-鼠李糖苷酶活力和柚苷酶活力的影响,优化黑曲霉DB056摇瓶发酵α-鼠李糖苷酶和柚苷酶的培养基。结果:碳氮源的种类与浓度,乳化剂Tri-tonX-100的浓度对黑曲霉DB056产α-鼠李糖苷酶和柚苷酶有重要影响;黑曲霉DB056产酶的优化培养基是:柚皮苷3.5g/L,玉米浆4g/L,MgSO4·7H2O1.0g/L,KH2PO41.0g/L,KCl0.5g/L,无水CaCl20.1g/L,乳化剂TritonX-1001.0%。此时α-鼠李糖苷酶活力和柚苷酶活力分别为994U/mL和276U/mL,分别比发酵初始培养基提高了42.3%和147.8%。结论:通过培养基优化,大幅度提高了黑曲霉DB056液态深层发酵α-鼠李糖苷酶活力和柚苷酶活力。

关键词：黑曲霉发酵培养基 α-鼠李糖苷酶柚苷酶高效液相色谱法

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柚皮果胶的提取及脱色工艺研究

泉州师范学院学报 2018年第6期36卷 14-19页

作者：陈艳红田友明肖琼吴昌正肖安风集美大学食品与生物工程学院福建厦门361021 福建省食品微生物与酶工程重点实验室福建厦门361021 厦门市食品与生物工程技术研究中心福建厦门361021 厦门南方海洋研究中心经济海藻资源化利用与深加工重点实验室福建厦门361021

以柚皮粉为原材料,果胶得率为指标,研究了酸法浸提柚皮果胶工艺中浸提温度、pH、浸提时间、液料比对柚皮果胶得率的影响.结果表明,柚皮果胶的最佳提取工艺为:浸提时间90min,浸提液pH 1.5,液料比(g/mL)20∶1,浸提温度100°C,在此条件下,... 详细信息

以柚皮粉为原材料,果胶得率为指标,研究了酸法浸提柚皮果胶工艺中浸提温度、pH、浸提时间、液料比对柚皮果胶得率的影响.结果表明,柚皮果胶的最佳提取工艺为:浸提时间90min,浸提液pH 1.5,液料比(g/mL)20∶1,浸提温度100°C,在此条件下,柚皮粗果胶得率达到19.9%.然后,以柚皮粗果胶为原料,考察了脱色剂的种类、脱色剂添加量、脱色时间、脱色温度及果胶醇沉条件对柚皮粗果胶脱色效果及最终得率的影响.结果表明,以珍珠岩为脱色剂,在添加量为2%,脱色温度为70°C,脱色时间为20min时,果胶脱色率最高为66.4%,当果胶浸提液与乙醇的体积比为5∶4时,果胶得率达到最大(11.5%).

关键词：柚皮果胶提取工艺脱色工艺优化