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提高木质纤维生物炼制效率的纤维素酶生产策略

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生物质化学工程 2024年第3期58卷 48-56页

作者：何颖慧张慧贾惜文丁凯丽刘烙阳肖卫华中国农业大学工学院北京100083

纤维素酶是木质纤维生物炼制过程中的关键要素,木质纤维的高效酶解为其生物炼制提供了巨大的机会。如何提高纤维素酶的效价、降低酶解成本,从而实现高效的木质纤维生物炼制是当前关注热点之一。本文综述了纤维素酶的种类及其作用机理,... 详细信息

纤维素酶是木质纤维生物炼制过程中的关键要素,木质纤维的高效酶解为其生物炼制提供了巨大的机会。如何提高纤维素酶的效价、降低酶解成本,从而实现高效的木质纤维生物炼制是当前关注热点之一。本文综述了纤维素酶的种类及其作用机理,重点分析了纤维素酶的微生物来源,生产纤维素酶的发酵方式及诱导剂,产纤维素酶菌株的筛选与改造,并对利用纤维素酶的复配提升纤维素酶活力和利用纤维素酶的在线生产降低纤维素酶生产成本进行阐述,并提出了更好地实现纤维素酶生产成本控制的策略。

关键词：纤维素酶木质纤维生物炼制

Elastic Predictions of 3D Orthogonal Woven Composites Using Micro/meso-scale Repeated Unit Cell Models

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Journal of Donghua University(English Edition) 2019年第4期36卷 390-398页

作者： jia xiwen GAO Limin ZHANG Tian ZHANG Fa WANG Yan Department of Structural Integrity Beijing Aeronautical Science & Technology Research Institute of COMAC

This presentation predicts the elastic properties of three-dimensional(3D)orthogonal woven composite(3DOWC)by finite element analysis based on micro/meso repeated unit cell(RUC)***,the properties of fiber yarn are obtained by analysis on a micro-scale RUC model assuming fibers in a hexagonal distribution pattern in the polymer *** a full thickness meso-scale RUC model including weft yarns,warp yarns,Z-yarns and pure resin zones is established and full stiffness matrix of the 3DOWC including the in-plane and flexural constants are *** thick 3DOWC with large number of weft,warp layers,an alternative analysis method is proposed in which an inner meso-RUC and a surface meso-RUC are established,*** the properties of 3DOWC are deduced based on laminate theory and properties of the inner and surface *** predicted results by the above two alternative methods are in good experimental agreement.

关键词： composite multi-scale analysis repeated unit cell model finite element method

Single-cell RNA sequencing in juvenile idiopathic arthritis

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Genes & Diseases 2024年第2期11卷 633-644页

作者： xiwen Luo Xuemei Tang Department of Rheumatology and Immunology Children’s Hospital of Chongqing Medical UniversityChongqing 400014China Chongqing Key Laboratory of Child Infection and Immunity Ministry of Education Key Laboratory of Child Development and DisordersNational Clinical Research Center for Child Health and DisordersChina International Science and Technology Cooperation Base of Child Development and Critical DisordersChildren's Hospital of Chongqing Medical UniversityChongqing 400014China

Juvenile idiopathic arthritis (jia) is one of the most common chronic inflammatory rheumatic diseases in children,with onset before age 16 and lasting for more than 6 *** is a highly heterogeneous condition with various consequences for health and quality of *** some jia patients,early detection and intervention remain *** a result,further investigation of the complex and unknown mechanisms underlying jia is *** in technology now allow us to describe the biological heterogeneity and function of individual cell populations in *** this review,we hope to provide novel ideas and potential targets for the diagnosis and treatment of jia by summarizing the current findings of single-cell RNA sequencing studies and understanding how the major cell subsets drive jia pathogenesis.

关键词： Juvenile idiopathic arthritis Macrophage Macrophage activation syndrome Monocyte Single-cell RNA sequencing Synoviocyte T cell

Study on the Efficacy of Vitamin C Lotion on Skin: Permeable and Anti-Aging

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Journal of Cosmetics, Dermatological Sciences and Applications 2022年第1期12卷 67-82页

作者： Mengping Wang Wangwang Lu Xinye Ge Yuan Lu xiwen jia Huiming Li Qiaoyuan Liu R & D Department Galenic Cosmetics Laboratory SAS Paris France

Vitamin C (ascorbic acid) plays an important role in maintaining skin health, and topical vitamin C supplementation can counteract oxidative stress induced by UVA, due to excellent reducibility. To clarify the efficacy of vitamin C on the skin in the carrier of lotion, we studied its permeability, irritation and anti-aging effect in vitro and in vivo, using Franz cell system, cell model and clinical test. The permeability test showed that vitamin C with 10%, 15%, 20% and 25% mass ratio could effectively penetrate skin. The 20% of vitamin C lotion (VCL-20%) had the highest efficiency of transdermal penetration and the diffusion percentage reached 84.707% after 24 h. Besides, the permeation quantity of VCL-20% was 1.43 times that of the control group. Irritation test showed that the cytotoxicity of vitamin C lotion was low. And no allergic reaction happened in the occlusive patch test. Compared with the control group, using vitamin C lotion for 28 days could significantly improve subjects’ skin gloss of 10.53% and improve skin color, enhance facial skin elasticity and tightness of 9.20% and reduce wrinkle area of 12.27% (p < 0.05).

关键词： Vitamin C Lotion Efficacy Transdermal Penetration Skin Whitening Anti-Aging

Carya cathayensis Leaf Extract Exerts Estrogenic Effects on Hepatic Lipogenesis and Adipocytes Differentiation in Ovariectomized Rats Fed Normal or High-fat Diets

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Clinical Complementary Medicine and Pharmacology 2023年第3期3卷 1-7页

作者： xiwen jia Simeng Guo Youling Huang Dongheng Zheng Yuqi Ding Xilin Qiao Zhishan Ding Yanfen Huang College of Life Science Zhejiang Chinese Medical UniversityHangzhou 310053ZhejiangChina College of Stomatology Zhejiang Chinese Medical UniversityHangzhou 310053ZhejiangChina College of Medical Technology Zhejiang Chinese Medical UniversityHangzhou 310053ZhejiangChina

Background:Our previous in vitro study has shown that total flavonoids from the leaves of Carya cathayensis exert estrogenic activities by promoting the expressions of ER𝛼and ER𝛽.*** leaf extract(CCE)was rich in *** administration of CCE reduced the serum lipids and hepatic lipids,alleviated liver steatosis in ovariectomized ***:To investigate whether CCE has estrogenic effects on reproductive tissue and influences lipid metabolism in ovariectomized rats,and whether CCE has a direct effect on regulation of lipid synthesis and/or oxidation and adipocyte differentiation of ovariectomized(OVX)***:Female Sprague-Dawley rats were ovariectomized and treated with CCE or estradiol in combination with a normal diet(ND),a high-fat diet(HFD)for 8 *** analysis of uterus were performed and the lipid metabolism-related enzyme activity were *** of liver lipogenesis-related genes,adipocyte differentiation-and fat accumulation-related genes and protein were ***:Ovariectomy accelerated the uterine atrophy,development of dyslipidemia and hepatic steatosis,which were effectively mitigated by CCE *** significantly elevated ovariectomy-induced reduction in the cross-section area of the uterus and uterine *** with the OVX group,CCE increased the activities of lipoprtein lipase(LPL)and hepatic lipase(HL),decreased the hepatic mRNA expressions of Fas,Srebf1,Sla2a2,and increased Ppar𝛼expressions at the mRNA levels under both ND and HFD *** also decreased the Pck1 and G6pc mRNA expressions under HFD conditions,and show no significant effects on *** expressions of SREBF1,CEBPA and VEGF at the protein level were effectively regulated by CCE ***:CCE effectively alleviated ovariectomy-induced dyslipidemia and visceral fat accumulation by mod-ulating hepatic lipogenesis and adipocyte ***,CCE exhibited estrogenic activit

关键词： Hepatic lipogenesis Adipocyte differentiation Ovariectomy Dyslipidemia Phytoestrogens

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车辆跳跃现象与传动系自激振动

中山大学学报论丛 1997年第5期17卷 178-182页

作者： jia jianzhang Luo xiwen Shao Mingliang

介绍了国内外对车辆跳跃现象的研究现状，并分析了跳跃现象产生的机理。

关键词：车辆跳跃现象传动系统自激振动

锰位掺杂La0.7Ba0.3Mn0.95X0.05O3(X=Mn,Cr,Fe,Co)薄膜光诱导特性研究

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稀有金属材料与工程 2010年第11期39卷 1952-1955页

作者：贾锡文陈长乐金克新王建元马强 NW Polytech Univ Dept Appl Phys Xian 710129 Peoples R China

用固相反应法制备La0.7Ba0.3Mn0.95X0.05O3(X=Mn,Cr,Fe,Co)系列块材,并利用磁控溅射法在LaAlO3单晶衬底上制备薄膜,研究过渡金属元素(Cr,Fe和Co)锰位掺杂对La0.7Ba0.3MnO3(LBMO)薄膜光诱导特性的影响。研究表明,Cr,Fe和Co掺杂均导致薄... 详细信息

用固相反应法制备La0.7Ba0.3Mn0.95X0.05O3(X=Mn,Cr,Fe,Co)系列块材,并利用磁控溅射法在LaAlO3单晶衬底上制备薄膜,研究过渡金属元素(Cr,Fe和Co)锰位掺杂对La0.7Ba0.3MnO3(LBMO)薄膜光诱导特性的影响。研究表明,Cr,Fe和Co掺杂均导致薄膜的金属-绝缘转变温度(TP)降低,电阻率和光致电阻率相对变化的最大值(LRmax)增大。其中Fe离子对体系影响最大,Co离子次之,Cr离子影响最小。激光诱导在不同温区对薄膜电阻率的影响不同,在低温(TTP)表现为光致电阻率减小。从过渡金属Cr,Fe和Co离子自身电子结构和晶格效应的角度出发,讨论了样品输运行为和光诱导特性的内在机理。

关键词：锰位掺杂薄膜电阻率光诱导特性特性研究离子影响过渡金属元素光致磁控溅射法转变温度相对变化高温区输运行为内在机理晶格效应激光诱导固相反应电子结构最大值离子对制备

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织物增强相对复合材料冲击压缩性质的影响

复合材料学报 2019年第1期36卷 122-132页

作者：张发胡震东万玉敏贾西文王专利中国商飞北京民用飞机技术研究中心民用飞机结构与复合材料北京市重点实验室北京102211 北京航空航天大学材料科学与工程学院北京100191

分别采用材料试验机(MTS)和分离式霍普金斯压杆(SPHB)测试系统研究二维平纹层压复合材料(2DWCs)、三维正交复合材料(3DOWCs)和三维编织复合材料(3DBCs)在准静态和高应变率压缩载荷下的力学响应和破坏形态。通过应力-应变曲线研究三种织... 详细信息

分别采用材料试验机(MTS)和分离式霍普金斯压杆(SPHB)测试系统研究二维平纹层压复合材料(2DWCs)、三维正交复合材料(3DOWCs)和三维编织复合材料(3DBCs)在准静态和高应变率压缩载荷下的力学响应和破坏形态。通过应力-应变曲线研究三种织物结构增强树脂基复合材料的应变率效应、应变率敏感性和能量吸收性质。通过破坏形态研究三种织物增强树脂基复合材料的破坏机制。结果显示:三种复合材料都具有明显的应变率效应。面外压缩时,2DWCs的压缩刚度、强度及应变率敏感性都最高,而3DBCs最弱;但当应变率大于1 500s-1后,3DBCs能量吸收能力最强,2DWCs能量吸收能力最弱;2DWCs增强相和3DOWCs增强相以剪切断裂形式为主,3DBCs增强相以"坍塌"压扁形式为主。面内压缩时,2DWCs的面内压缩刚度最大而面内能量吸收能力最弱,3DOWCs的面内压缩强度最高,3DBCs的断裂应变最大、面内能量吸收能力及应变率敏感性最高,2DWCs增强相以分层破坏为主,3DOWCs和3DBCs以端面膨胀破坏为主。

关键词：织物复合材料冲击压缩影响机制

玉米秸秆基木质素-醋酸纤维素紫外屏蔽膜的制备及其性能

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复合材料学报 2023年第8期40卷 4768-4778页

作者：林昊郭东毅吕谦贾惜文周成凤肖卫华中国农业大学工学院北京100083 青岛大学省部共建生物多糖纤维成形与生态纺织国家重点实验室青岛266071

为减少紫外线对人类造成的伤害和设施的破坏,本文以过氧乙酸复合马来酸预处理(PAM)玉米秸秆得到的纤维素产物为原料,以三氟乙酸作为催化剂和溶剂通过相转化法制备具有紫外屏蔽功能的玉米秸秆基醋酸纤维素膜。随着PAM预处理温度的提高,... 详细信息

为减少紫外线对人类造成的伤害和设施的破坏,本文以过氧乙酸复合马来酸预处理(PAM)玉米秸秆得到的纤维素产物为原料,以三氟乙酸作为催化剂和溶剂通过相转化法制备具有紫外屏蔽功能的玉米秸秆基醋酸纤维素膜。随着PAM预处理温度的提高,乙酰化程度和醋酸纤维素产率分别增加到42.19%和93.97%。制得的醋酸纤维素膜(ZCA-80~ZCA-120)的光学性能表征结果表明:该醋酸纤维素膜紫外线屏蔽性能良好,ZCA-110的中波紫外线(UVB)和长波紫外线(UVA)屏蔽率分别达到96.51%和73.72%。同时,揭示了ZCA-80~ZCA-120在紫外光区(200~400 nm)的屏蔽率及在660 nm处的透光率(T_(660))与木质素含量的相关关系,表明木质素含量是决定醋酸纤维素膜紫外屏蔽性能的关键因素。采用紫外分光光度计、接触角测试仪、XRD和FTIR对未添加壳聚糖(ZCA-110)和添加壳聚糖(CS/ZCA-5)的醋酸纤维素膜进行比较研究,发现添加壳聚糖的膜透光率得到改善、亲水性增强、结晶度降低。本文制备的木质纤维基醋酸纤维素膜将为生物可降解紫外屏蔽材料的研发提供新思路。

关键词：玉米秸秆木质素醋酸纤维素膜紫外屏蔽透光率壳聚糖