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Copper Tetrahydrosalen Complex Encapsulated in Zeolite Y:an Effective Heterogeneous Catalyst for the Oxidation of Cycloalkanes

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Chinese Chemical Letters 2006年第3期17卷 419-422页

作者： chun jin yin Juan JIA Bin Bin FAN jing Hong MA Rui Feng LI Key Laboratory of Coal Science and Technology MOE Institute of Special Chemicals Taiyuan University of Technology Talyuan 030024

A new heterogeneous catalyst, copper tetrahydrosalen complex encapsulated in zeolite Y （denoted as Cu[H4]salen/Y） has been developed with flexible ligand method, and characterized by FTIR, DR UV-Vis spectroscopy, N2 adsorption/desorption at -196℃. This catalyst behaved like a bio-mimic enzyme, and exhibited much higher activity for the oxidation of cycloalkanes than Cusalen/Y prepared with the same method. The effects of the reaction conditions on the catalytic performance were investigated.

关键词： Copper tetrahydrosalen complex zeolite Y encapsulation cyclohexane oxidation.

Aligning enhanced feature representation for generalized zero-shot learning

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Science China(Information Sciences) 2025年第2期68卷 74-88页

作者： Zhiyu FANG Xiaobin ZHU chun YANG Hongyang ZHOU jingyan QIN Xu-Cheng yin School of Computer & Communication Engineering University of Science and Technology Beijing

Constructing an effective common latent embedding by aligning the latent spaces of cross-modal variational autoencoders（VAEs） is a popular strategy for generalized zero-shot learning（GZSL）. However, due to the lack of fine-grained instance-wise annotations, existing VAE methods can easily suffer from the posterior collapse problem. In this paper, we propose an innovative asymmetric VAE network by aligning enhanced feature representation（AEFR） for GZSL. Distinguished from general VAE structures, we designed two asymmetric encoders for visual and semantic observations and one decoder for visual reconstruction. Specifically, we propose a simple yet effective gated attention mechanism（GAM） in the visual encoder for enhancing the information interaction between observations and latent variables, alleviating the possible posterior collapse problem effectively. In addition, we propose a novel distributional decoupling-based contrastive learning（D2-CL） to guide learning classification-relevant information while aligning the representations at the taxonomy level in the latent representation space. Extensive experiments on publicly available datasets demonstrate the state-of-the-art performance of our method. The source code is available at https://***/seeyourmind/AEFR.

关键词： generalized zero-shot learning gated attention mechanism contrastive learning multi-modal alignment

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Gentiopicroside Alleviates Atherosclerosis by Suppressing Reactive Oxygen Species-Dependent NLRP3 Inflammasome Activation in Vascular Endothelial Cells via SIRT1/Nrf2 Pathway

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Chinese Journal of Integrative Medicine 2025年第2期31卷 118-130页

作者： LI Zhu-qing ZHANG Feng LI Qi WANG Li SUN Xiao-qiang LI Chao yin Xue-mei LIU chun-lei WANG Yan-xin DU Xiao-yu LU Cheng-zhi Department of Cardiology Tianjin First Central HospitalTianjin300192China The First Central Clinical School Tianjin Medical UniversityTianjin300070China Department of Cardiology The First College of Clinical Medical ScienceChina Three Gorges University&Yichang Central People’s HospitalYichangHubei Province443003China School of Medicine Nankai UniversityTianjin300071China

Objective:To evaluate the protective effects of gentiopicroside(GPS)against reactive oxygen species(ROS)-induced NOD-like receptor family,pyrin domain containing 3(NLRP3)inflammasome activation in endothelial cells,aiming to reduce ***:Eight-week-old male ApoE-deficient mice were randomly divided into 2 groups(n=10 per group):the vehicle group and the GPS treatment *** groups were fed a high-fat diet for 16 ***(40 mg/kg per day)was administered by oral gavage to the GPS group,while the vehicle group received an equivalent volume of the vehicle *** the end of the treatment,blood and aortic tissues were collected for assessments of atherosclerosis,lipid profiles,oxidative stress,and molecular expressions related to NLRP3 inflammasome activation,ROS production,and ***,in vitro experiments on human aortic endothelial cells treated with oxidized low-density lipoprotein(ox-LDL)were conducted to evaluate the effects of GPS on NLRP3 inflammasome activation,pyroptosis,apoptosis,and ROS production,specifically examining the role of the sirtuin 1(SIRT1)/nuclear factor erythroid 2-related factor 2(Nrf2)***1 and Nrf2 inhibitors were used to confirm the pathway's ***:GPS treatment significantly reduced atherosclerotic lesions in the en face aorta(P<0.01),as well as in the thoracic and abdominal aortic regions,and markedly decreased sinus lesions within the aortic root(P<0.05 or P<0.01).Additionally,GPS reduced oxidative stress markers and proinflammatory cytokines,including interleukin(IL)-1βand IL-18,in lesion areas(P<0.05,P<0.01).In vitro,GPS inhibited ox-LDL-induced NLRP3 activation,as evidenced by reduced NLRP3(P<0.01),apoptosis-associated speck-like protein containing a CARD,cleaved-caspase-1,and cleavedgasdermin D expressions(all P<0.01).GPS also decreased ROS production,apoptosis,and pyroptosis,with the beneficial effects being significantly reversed by SIRT1 or Nrf2 ***:GPS exe

关键词： endothelial dysfunction gentiopicroside NLRP3 inflammasome SIRT1 nuclear factor erythroid 2-related factor 2 Chinese medicine

区域科技创新中心支撑高质量发展的理论逻辑和实现路径研究：以中国西部（重庆）科学城为例

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科学学与科学技术管理 2025年第1期46卷 122-136页

作者：袁野祖纯尹西明陈劲重庆邮电大学经济管理学院北京理工大学管理学院清华大学技术创新研究中心清华大学经济管理学院

建设高水平的区域科技创新中心是培育新质生产力、实现高质量发展的战略支撑，但鲜有研究揭示其内在理论逻辑和实现路径。为此，以中国西部（重庆）科学城为例，采用探索性单案例研究方法，揭示创新驱动发展战略与区域高质量发展有机衔... 详细信息

建设高水平的区域科技创新中心是培育新质生产力、实现高质量发展的战略支撑，但鲜有研究揭示其内在理论逻辑和实现路径。为此，以中国西部（重庆）科学城为例，采用探索性单案例研究方法，揭示创新驱动发展战略与区域高质量发展有机衔接的构成要素、传导机制、模式分类和驱动机理。以北京等为代表的技术驱动型科技创新中心，形成了以国家战略科技力量为牵引、关键核心技术持续供给的发展模式；以深圳等为代表的场景驱动型科技创新中心，形成了场景驱动、产业牵引、企业主导、政府培育创新环境的发展模式；以重庆等为代表的政策驱动型科技创新中心，形成了国家战略为牵引，构建政策创新、政策调整、政策落实的高质量支撑模式。研究发现在中国西部（重庆）科学城建设区域科技创新中心进程中，支撑高质量发展的主要路径有六条：第一，以深化制度创新为抓手，统筹科技创新与高质量发展。第二，打造国家战略科技力量，合作共建国家级创新平台。第三，构建原始创新策源体系，加快关键核心技术攻关。第四，持续优化区域创新生态，赋能现代化产业体系建设。第五，健全人才服务体系，激发人才创新创造活力。第六，深入推进成渝双城协同，共建西部内陆开放新高地。

关键词：中国式现代化高质量发展区域科技创新中心科技自立自强新质生产力

一贯煎加减对慢性萎缩性胃炎IL-12和TNF-α的影响

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中国实验方剂学杂志 2012年第11期18卷 248-250页

作者：邱志洁伊春锦李新民叶颖王玲玉福建省立医院福州350001 福建中医药大学福州350001

目的:了解一贯煎加减辅助治疗慢性萎缩性胃炎的效果,及治疗后患者血清中白细胞介素-12(IL-12)和肿瘤坏死因子-α(TNF-α)的变化。方法:选择在我院确诊的慢性萎缩性胃炎患者,共86例,依患者入院顺序分为观察组(43)与对照组(43例)。观察组... 详细信息

目的:了解一贯煎加减辅助治疗慢性萎缩性胃炎的效果,及治疗后患者血清中白细胞介素-12(IL-12)和肿瘤坏死因子-α(TNF-α)的变化。方法:选择在我院确诊的慢性萎缩性胃炎患者,共86例,依患者入院顺序分为观察组(43)与对照组(43例)。观察组在常规治疗上加用一贯煎加减进行治疗,对照组应用常规性的治疗。观察二组治疗后的临床效果及对血清中IL-12和TNF-α的影响。结果:观察组患者的总有效率(95.35%)明显高于对照组(81.40%),治疗后观察组血清中IL-12和TNF-α的表达[(121.11±6.24),(36.72±10.76)ng.L-1]明显低于对照组[(31.21±7.73),(54.75±9.87)ng.L-1]。结论:一贯煎加减治疗慢性萎缩性胃炎的疗效明显,且能有效下调血清中IL-12和TNF-α的表达,从机体微环境中进行调节,临床治疗中可以应用。

关键词：中药一贯煎慢性萎缩性胃炎白细胞介素-12 肿瘤坏死因子-α

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抗菌聚合物结构色微球的制备及性能

高分子通报 2025年第1期38卷 109-115页

作者：陶伟晗方寅春安徽工程大学纺织服装学院芜湖241000

采用无皂乳液聚合方法,以甲基丙烯酸甲酯(MMA)、苯乙烯(St)和丙烯酰氧乙基三甲基氯化铵(DAC),合成不同粒径的P(St-MMA-DAC)聚合物微球,通过雾化沉积法在涤纶织物上制备结构色。对P(St-MMA-DAC)聚合物微球及结构色织物进行了红外光谱、... 详细信息

采用无皂乳液聚合方法,以甲基丙烯酸甲酯(MMA)、苯乙烯(St)和丙烯酰氧乙基三甲基氯化铵(DAC),合成不同粒径的P(St-MMA-DAC)聚合物微球,通过雾化沉积法在涤纶织物上制备结构色。对P(St-MMA-DAC)聚合物微球及结构色织物进行了红外光谱、扫描电镜、粒径、反射光谱和抗菌性能测试。结果表明,通过改变合成过程中单体比例可以得到不同粒径的P(St-MMA-DAC)聚合物微球,可在涤纶织物上形成蓝色、粉红色、绿色、青色和紫色5种不同颜色的结构色。结构色织物对大肠杆菌(***)和金黄色葡萄球菌(***)的抑菌率可达到98%以上,表现出优异的抗菌性能。本文为功能性聚合物微球开发及在纺织、医疗卫生等领域的应用提供了研究基础。

关键词：结构色聚合物微球功能性抗菌

Functional Cellulose Materials Fabricated by Using Ionic Liquids as the Solvent

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Chinese Journal of Polymer Science 2023年第4期41卷 483-499,I0005页

作者： Yi-Rong Wang chun-chun yin jin-Ming Zhang jin Wu Jian Yu Jun Zhang CAS Key Laboratory of Engineering Plastics and CAS Research/Education Center for Excellence in Molecular Sciences Institute of ChemistryChinese Academy of SciencesBeijing100190China College of Chemistry University of Chinese Academy of SciencesBeijing100049China

Cellulose is one of the most abundant natural polymers in the nature,which has many attractive advantages,such as renewability,biodegradability,and ***,due to the strong hydrogen bond network and hierarchical structure,cellulose is extremely difficult to be dissolved and *** recently,a class of novel eco-friendly solvents,ionic liquids,have been found to be able to efficiently dissolve cellulose,providing a versatile platform for cellulose processing and ***,we highlight recent advances in efficiently fabricating functional cellulose derivatives via the homogeneous chemical modification and developing all-biomass materials via controlling the dissolution-regeneration process in ionic *** effective and environmentally-friendly utilization of cellulose not only reduces dependence on fossil resources but also protects the environment.

关键词： Cellulose Ionic liquids Homogeneous modification Functional materials Cellulose derivatives

不同地表覆盖旱作水稻和水作水稻水分利用效率的研究

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水土保持学报 2003年第3期17卷 140-143页

作者：黄新宇徐阳春沈其荣周春霖尹金来 Dittert K 南京农业大学资环学院南京210095 江苏省盐城市农科所盐城224002 德国基尔大学

通过田间试验研究不同地表覆盖旱作水稻和水作水稻全生育期内水分需求特征与水分利用效率。结果表明,水作稻田当季用水总量是旱作稻田的3倍多,旱作盖草处理的灌溉量为434.5m3/hm2,仅相当于水作的24.6%。不同处理的水分利用效率为:盖草>... 详细信息

通过田间试验研究不同地表覆盖旱作水稻和水作水稻全生育期内水分需求特征与水分利用效率。结果表明,水作稻田当季用水总量是旱作稻田的3倍多,旱作盖草处理的灌溉量为434.5m3/hm2,仅相当于水作的24.6%。不同处理的水分利用效率为:盖草>覆膜>裸露>水作,且旱作与水作间差异极显著。水作、覆膜、盖草和裸露的产量分别为:8250,7207,7867,7253kg/hm2,统计分析结果显示,盖草旱作与水作间产量差异不显著,这表明盖草旱作是一项效果最好的技术。

关键词：地表覆盖水稻旱作水作水分利用效率水分需求特征产量

Suppression of Spiral Wave in Modified Orengonator Model

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Communications in Theoretical Physics 2008年第8期50卷 403-410页

作者： MA Jun jin Wu-yin YI Ming WANG chun-Ni Department of Physics Lanzhou University of Technology Lanzhou 730050 China Department of Physics Central China Normal University Wuhan 430079 China College of Mechano-Electronic Engineering Lanzhou University of Technology Lanzhou 730050 China

In this paper, a spatial perturbation scheme is proposed to suppress the spiral wave in the modified Orengonator model, which is used to describe the chemical reaction in the light-sensitive media. The controllable external illumination Ф is perturbed with a spatial linear function. In our numerical simulation, the scheme is investigated by imposing the external controllable illumination on the space continuously and/or intermittently. The numerical simulation results confirm that the stable rotating spiral wave still can be removed with the scheme proposed in this paper even if the controllable Ф changed vs. time and space synchronously. Then the scheme is also used to control the spiral wave and turbulence in the modified Fitzhugh-Nagumo model. It is found that the scheme is effective to remove the sable rotating and meandering spiral wave but it costs long transient period and intensity of the gradient parameter to eliminate the soiral turbulence.

关键词： spiral wave spatial perturbation Orengonator model modified Fitzhugh-Nagumo model