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体外消化对金瓜籽抗氧化肽抗氧化活性的影响

食品科学 2019年第3期40卷 78-86页

作者：陈丽花朱楚楚李冉冉上海应用技术大学食品科学与工程系上海201418

本实验以金瓜籽为原料,以还原力、羟自由基清除率、DPPH自由基清除率为考察指标,采用响应面试验探讨了制备金瓜籽抗氧化肽的工艺参数,并研究了其经体外模拟人体胃肠道消化后的游离氨基酸组成、分子质量分布及抗氧化活性变化。结果表明:... 详细信息

本实验以金瓜籽为原料,以还原力、羟自由基清除率、DPPH自由基清除率为考察指标,采用响应面试验探讨了制备金瓜籽抗氧化肽的工艺参数,并研究了其经体外模拟人体胃肠道消化后的游离氨基酸组成、分子质量分布及抗氧化活性变化。结果表明:制备金瓜籽抗氧化肽的最优工艺条件为底物(金瓜籽粕)质量分数为6%、添加碱性蛋白酶3%、在pH 8.5的体系中55℃酶解90 min,此条件下所得羟自由基清除率、DPPH自由基清除率、还原力分别为(58.19±0.80)%、(60.27±1.73)%和0.49±0.01;分子质量小于3 kDa、3～5 kDa及大于5 kDa的抗氧化肽经体外模拟胃肠道消化后分别含游离氨基酸41.72%、36.94%和33.93%,其主要为分子质量小于500 Da的肽段,占比分别为73.50%、60.15%和53.30%;与消化前相比,消化产物对羟自由基的清除能力分别提高了26.04%、29.06%和34.43%,还原力分别提高了50.98%、64.53%、67.35%。该研究可为金瓜籽抗氧化肽作为功能性抗氧化剂的生产和应用提供参考。

关键词：金瓜籽抗氧化肽体外模拟消化游离氨基酸分子质量分布抗氧化活性

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再谈信息特性问题——兼与张辑哲教授商榷

科技情报开发与经济 2014年第8期24卷 113-115,118页

作者：朱处处安徽大学管理学院安徽合肥230601

信息理论领域已有许多对信息特性的研究。张辑哲教授在《深论信息特性》一文中论述了已有信息理论对信息特性研究的粗浅与错谬。在对张教授观点剖析的基础上,指出了张教授对于信息不可替代性的阐释具有绝对化和自相矛盾的地方,同时提出... 详细信息

信息理论领域已有许多对信息特性的研究。张辑哲教授在《深论信息特性》一文中论述了已有信息理论对信息特性研究的粗浅与错谬。在对张教授观点剖析的基础上,指出了张教授对于信息不可替代性的阐释具有绝对化和自相矛盾的地方,同时提出了更为重要的信息特性——时效性、可伪性和转化性。

关键词：信息特性可替代性时效性可伪性转化性

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基于推拉理论的北京博物馆旅游驱动因素研究

四川旅游学院学报 2020年第4期 76-81页

作者：祝楚楚王静北京联合大学旅游学院北京100101

文化旅游的深度融合使得博物馆旅游日益火热,研究博物馆旅游的驱动因素有助于博物馆旅游的可持续发展,也有益于提升博物馆的竞争力。基于推拉理论,通过实证研究并结合因子分析等方法研究发现:(1)推力包括“休闲娱乐”“求知教育”和“... 详细信息

文化旅游的深度融合使得博物馆旅游日益火热,研究博物馆旅游的驱动因素有助于博物馆旅游的可持续发展,也有益于提升博物馆的竞争力。基于推拉理论,通过实证研究并结合因子分析等方法研究发现:(1)推力包括“休闲娱乐”“求知教育”和“社交需要”三个驱动因素;拉力包括“展览质量”“区位和价格”和“展馆环境”三个驱动因素。(2)推力驱动因素和拉力驱动因素的内部一致性较高。(3)拉力驱动因素与出游综合评价正相关性更高。基于此,进行了相关的讨论并给出了博物馆发展的相关建议。

关键词：推拉理论博物馆旅游驱动因素

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锚杆与锚索协同锚固的能量分析研究

煤炭与化工 2023年第11期46卷 18-24页

作者：张新过党鹏远朱初初河南能源化工集团永煤公司城郊煤矿河南商丘476600 中国矿业大学力学与土木工程学院江苏徐州221008

地下工程围岩的变形、破坏及失稳过程中始终伴随着能量的转化和转移,支护体对围岩体的变形失稳具有一定的控制作用,对锚固体和围岩内能量的转化和转移也有影响。本文以Mohr-Coulomb准则为依据,从能量角度分析了圆形巷道开挖后围岩内弹... 详细信息

地下工程围岩的变形、破坏及失稳过程中始终伴随着能量的转化和转移,支护体对围岩体的变形失稳具有一定的控制作用,对锚固体和围岩内能量的转化和转移也有影响。本文以Mohr-Coulomb准则为依据,从能量角度分析了圆形巷道开挖后围岩内弹性应变能和塑性应变能在围岩中的分布情况和影响因素。指出在破碎区围岩的力学参数中,粘聚力相比内摩擦角对围岩能量分布影响较大。注浆和提高锚杆预应力可以增大岩体的粘聚力,粘聚力的增加可以减少破碎区范围,但会加剧塑性能的集聚,需要配以组合锚索为锚固体提供均布支护力,减弱围岩塑性能集聚效应。为保证锚杆与锚索协同工作,其预应力必须相互匹配,且锚杆和锚索的预应力应与锚杆的弹性模量相匹配,在减少破碎区范围的同时,减弱塑性破坏能集聚程度,降低围岩弹性能,使围岩处于少破碎、均匀破碎和低能量的稳定状态。

关键词：能量分析应变能密度协同锚固预应力围岩弹性能巷道稳定性

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围岩松动圈敏感因素解析分析

煤炭与化工 2023年第10期46卷 1-6,48页

作者：臧冬冬曾朝辰张洋朱初初中国矿业大学力学与土木工程学院江苏徐州221116 河南能源集团永煤公司城郊煤矿河南永城476600

采用解析方法,分析讨论了巷道围岩进入破裂状态后围岩内的应力分布以及围岩松动圈范围的计算方法,在此基础上,重点采用MATLAB软件,利用控制变量法分析了影响围岩松动圈范围大小的敏感因素,是对围岩松动圈巷道支护理论的补偿和完善。论... 详细信息

采用解析方法,分析讨论了巷道围岩进入破裂状态后围岩内的应力分布以及围岩松动圈范围的计算方法,在此基础上,重点采用MATLAB软件,利用控制变量法分析了影响围岩松动圈范围大小的敏感因素,是对围岩松动圈巷道支护理论的补偿和完善。论文获得以下主要结论:①在理想弹塑性情况下,是无法确定松动圈范围的大小,而利用塑性位势理论求出塑性应变并补充径向应变在松动圈与塑性区交界处相等的条件就可以确定松动圈范围的大小;②影响松动圈范围的敏感因素是原岩力学参数和原岩应力,而支护力和松动圈内围岩的粘聚力对松动圈范围的影响较弱;③松动圈内围岩的粘聚力在有限范围内对松动圈范围影响显著,注浆加固可有效提高围岩的粘聚力,进而可在有限限度内减少松动圈范围;④理论上证明了支护力对松动圈范围的影响较小,在现有支护条件下可忽略不计。

关键词：围岩松动圈敏感因素支护力解析方法

Drag Reduction in the Mouthpart of a Honeybee Facilitated by Galea Ridges for Nectar-Dipping Strategy

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Journal of Bionic Engineering 2015年第1期12卷 70-78页

作者： chuchu Li Jianing Wu Yunqiang Yang Rengao zhu Shaoze Yan Division of Intelligent and Biomechanical Systems State Key Laboratory of Tribology Department of Mechanical Engineering Tsinghua University Beijing 100084 China School of Engineering and Technology China University of Geosciences Beijing 100083 China

Some nectarivorous animals have evolved highly specialized tongues to gather nectar from flowers. Here we show that the Italian honeybee, Apis mellifera ligustica, uses the uniformly-distributed ridges on the internal wall of the mouthpart to reduce drag while drinking nectar. We discovered that the tip of the tongue is covered with bushy setae and resembles a brush, and the ridges are parallel distributed on the inner wall of the galeae. Using high-speed camera, we recorded the morphology of the mouthpart when dipping the sucrose water. Considering the ridges and the movement rule of the glossa, we proposed a model for analyzing the mechanism of drag reduction. Theoretical estimation of the friction coefficient with respect to the dipping frequency indicates that the erectable bushy hairs and the ridges can significantly reduce friction when a honeybee drinks nectar. Results show that dimensions of the ridges play a key role in reducing friction. It can be concluded that the ridges on the galeae of honeybee＇s mouthpart can reduce the friction coefficient by 86% compared with the case of the transverse distribution co- efficient S = 40. Finally, the capability of drag reduction in the mouthpart of honeybee may inspire a creative concept for de- signing efficient viscous micropumps.

关键词： honeybee mouthpart ridges drag reduction micropump

The Honeybee＇s Protrusible Glossa is a Compliant Mechanism

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Journal of Bionic Engineering 2017年第4期14卷 607-615页

作者： Yunqiang Yang Jianing Wu Rengao zhu chuchu Li Shaoze Yan School of Engineering and Technology China University of Geosciences (Beijing) Beijing 100083 China Division of lntelligent and Biomechanical Systems State Key Laboratory of Tribology Department of Mechanical Engineering Tsinghua University Beijing 100084 China

Many biological structures can perform highly-dexterous actions by using dynamic surfaces. To deal with the contradictive demands of high feeding efficiency and low energy expenditure during nectar feeding, the glossal surface of a honeybee un- dergoes shape changes, in which glossal hairs erect together with segment elongation in a drinking cycle. In this paper, we extracted a transmission link embedded in the glossa from postmortem examination and found that the compliance of the in- tersegmental membranes provides more possibilities for this highly kinematic synchronicity. According to the morphing phe- nomena of honeybee＇s glossa, we proposed a compliant mechanism model to predict the deformation behavior of honeybee considering elastic properties of the glossal intersegmental membranes. The increase of membrane stiffness may improve the capacity of elastic potential energy transfer, but will still result in the increase of mass. An index is introduced to evaluate the contradiction for optimizing structural parameters. This work may arouse new prospects for conceptual design of mi- cro-mechanical systems equipped with bio-inspired compliant mechanisms.

关键词： honeybee glossal membrane compliant mechanism stiffness evaluation

Rod-shape inorganic biomimetic mutual-reinforcing MnO2-Au nanozymes for catalysis-enhanced hypoxic tumor therapy

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Nano Research 2020年第8期13卷 2246-2258页

作者： Lifang Yang chuchu Ren Min Xu Yilin Song Qianglan Lu Yule Wang Yan zhu Xinxing Wang Nan Li Tianjin Key Laboratory of Drug Delivery&High-Efficiency School of Pharmaceutical Science and TechnologyTianjin UniversityTianjin300072China Tianjin State Key Laboratory of Modern Chinese Medicine Tianjin University of Traditional Chinese MedicineBeihua South RoadJingHai DistrictTianjin301617China Research and Development Center of TCM Tianjin International Joint Academy of Biotechnology and Medicine220 Dongting RoadTEDATianjin300457China Tianjin Institute of Environmental and Operational Medicine 1 Dali RoadHeping DistrictTianjin300050China

Biomimetic nanozymes possessing natural enzyme-mimetic activities have been extensively applied in nanocatalytic tumor ***,engineering hybrid biomimetic nanozymes to achieve superior nanozyme activity remained to be an intractable challenge in hypoxic ***,a rod-like biomimetic hybrid inorganic MnO2-Au nanozymes are developed,where MnO2 and ultrasmall Au nanoparticles(NPs)are successively deposited on the mesoporous silica nanorod to cooperatively improve the O2 content and thermal sensitivity of hypoxic solid tumors guided by multi-modal *** the catalyzing of MnO2,the intratumoral H2O2 is decomposed to greatly accelerate O2 generation,which could boost the curative effect of radiation therapy(RT)and further enhance the Au-catalyzed glucose ***,the Au NPs can steadily and efficiently catalyze the oxidation of glucose in harsh tumor microenvironment,thus sensitizing tumor cells to thermal ablation for mild photothermal therapy and further promoting the catalytic efficiency of MnO2 with the self-supplied H2O2/H+.As a result,this mutual-reinforcing cycle can endow the nanoplatform with accelerated O2 generation,thus alleviating hypoxic environment and further boosting RT ***,acute glucose consuming can induce downregulation expression of heat shock protein(HSP),achieving starvation-promoted mild photothermal *** synthesized hybrid nanozymes proves to be a versatile theranostic agent for nanocatalytic cancer therapy.

关键词： nanozyme self-supplied mutual-reinforcing hypoxia catalysis-enhanced therapy

NIR-II driven plasmon-enhanced cascade reaction for tumor microenvironment-regulated catalytic therapy based on bio-breakable Au-Ag nanozyme

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Nano Research 2020年第8期13卷 2118-2129页

作者： Min Xu Qianglan Lu Yiling Song Lifang Yang chuchu Ren Wen Li Ping Liu Yule Wang Yan zhu Nan Li Tianjin Key Laboratory of Drug Delivery&High-Efficiency School of Pharmaceutical Science and TechnologyTianjin UniversityTianjin300072China Tianjin State Key Laboratory of Modern Chinese Medicine Tianjin University of Traditional Chinese MedicineTianjin301617China Research and Development Center of TCM Tianjin International Joint Academy of Biotechnology and MedicineTianjin300457China

Emerging nanozymes with natural enzyme-mimicking catalytic activities have inspired extensive research interests due to their high stability,low cost,and simple preparation,especially in the field of catalytic tumor ***,bio-breakable nanozymes based on glucose-oxidase(GOx)-loaded biomimetic Au–Ag hollow nanotriangles(Au–Ag–GOx HTNs)are designed,and they trigger an near-infrared(NIR)-II-driven plasmon-enhanced cascade catalytic reaction through regulating tumor microenvironment(TME)for highly efficient tumor ***,GOx can effectively trigger the generation of gluconic acid(H+)and hydrogen peroxide(H2O2),thus depleting nutrients in the tumor cells as well as modifying TME to provide conditions for subsequent peroxidase(POD)-like ***,NIR-II induced surface plasmon resonance can induce hot electrons to enhance the catalytic activity of Au–Ag–GOx HTNs,eventually boosting the generation of hydroxyl radicals(•OH).Interestingly,the generated H2O2 and H+can simultaneously induce the degradation of Ag nanoprisms to break the intact triangle nanostructure,thus promoting the excretion of Au–Ag–GOx HTNs to avoid the potential risks of drug ***,the NIR-II driven plasmon-enhanced catalytic mechanism of this bio-breakable nanozyme provides a promising approach for the development of nanozymes in tumor therapy.

关键词： near-infrared(NIR)-II driven plasmon-enhanced catalysis Au-Ag hollow nan otria ngles bio-breakable cascade reaction