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响应面法对金银花叶总黄酮与绿原酸同步萃取工艺的优化

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山东化工 2024年第12期53卷 4-8,12页

作者：李华生周振华骆航龙鸣陈瑛永州职业技术学院湖南永州425100

采用响应面法,对加压辅助溶剂同步萃取金银花叶总黄酮和绿原酸的工艺进行了优化。在单因素试验的基础上,综合评价总黄酮和绿原酸的得率“OD值”作为因变量,通过响应面法优化了液料比、萃取压力、溶剂体积分数、萃取温度和萃取时间。结... 详细信息

采用响应面法,对加压辅助溶剂同步萃取金银花叶总黄酮和绿原酸的工艺进行了优化。在单因素试验的基础上,综合评价总黄酮和绿原酸的得率“OD值”作为因变量,通过响应面法优化了液料比、萃取压力、溶剂体积分数、萃取温度和萃取时间。结果表明,优化后的加压辅助溶剂同步萃取工艺参数为:液料比26.5 mL/g,萃取压力3.1 MPa,溶剂体积分数60.5%,萃取温度90.3℃,萃取时间32 min。该工艺条件下,从金银花叶中萃取总黄酮得率为205.3 mg/g,绿原酸得率为24.5 mg/g, OD值与理论预测值的相对误差为1.0%。

关键词：响应面分析金银花叶总黄酮绿原酸加压萃取工艺

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滇中地区元江栲常绿阔叶林天然更新及其影响因子研究

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西南林业大学学报（自然科学） 2024年第1期44卷 88-96页

作者：罗航彭泽喜李小英许彦红朱洪琴陈玉强陈晓琴期俊程西南林业大学云南昆明650233 玉溪市林业和草原局云南玉溪653199

以滇中地区元江栲林为调查对象,采用熵值法对该林分更新效果进行综合评价,运用Pearson相关分析法、建立路径分析模型对其林下更新的影响因子。结果表明:26个元江栲常绿阔叶林样地中更新指数达到0.6以上的样地为10个,占比38.5%,其林下天... 详细信息

以滇中地区元江栲林为调查对象,采用熵值法对该林分更新效果进行综合评价,运用Pearson相关分析法、建立路径分析模型对其林下更新的影响因子。结果表明:26个元江栲常绿阔叶林样地中更新指数达到0.6以上的样地为10个,占比38.5%,其林下天然更新效果一般,但更新树种较为丰富,共18种,隶属于9个科15个属,森林处于缓慢的正向演替自然修复阶段。土壤孔隙度(r=0.848,P 土壤含水量(0.461)>灌草盖度(0.361)>株数密度(–0.108)>枯落物蓄积(–0.018)。在后续经营中,可通过人工疏伐、适当清理枯落物和改善土壤条件等经营方式促进元江栲常绿阔叶林林下天然更新,实现元江栲常绿阔叶林森林生态系统的稳定和可持续经营。

关键词：元江栲天然更新影响因子更新指数路径分析

Pannexins in the musculoskeletal system:new targets for development and disease progression

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Bone Research 2024年第2期12卷 255-269页

作者： Yan luo Shengyuan Zheng Wenfeng Xiao hang Zhang Yusheng Li Department of Orthopedics Xiangya HospitalCentral South UniversityChangshaHunan 410008China National Clinical Research Center for Geriatric Disorders Xiangya HospitalCentral South UniversityChangshaHunan 410008China Department of Clinical Medicine Xiangya Medicine SchoolCentral South UniversityChangshaHunan 410008China Shenzhen Institute of Advanced Technology Chinese Academy of SciencesShenzhen 518055China

During cell differentiation,growth,and development,cells can respond to extracellular stimuli through communication ***(Panx)family and connexin(Cx)family are two important types of channel-forming *** family contains three members(Panx1-3)and is expressed widely in bone,cartilage and *** there is no sequence homology between Panx family and Cx family,they exhibit similar configurations and *** to Cxs,the key roles of Panxs in the maintenance of physiological functions of the musculoskeletal system and disease progression were gradually revealed ***,we seek to elucidate the structure of Panxs and their roles in regulating processes such as osteogenesis,chondrogenesis,and muscle *** also focus on the comparison between Cx and *** a new key target,Panxs expression imbalance and dysfunction in muscle and the therapeutic potentials of Panxs in joint diseases are also discussed.

关键词： skeletal diseases system

Hydrogenase as the basis for green hydrogen production and utilization

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Journal of Energy Chemistry 2023年第10期85卷 348-362,I0011页

作者： Haishuo Ji Lei Wan Yanxin Gao Ping Du Wenjin Li hang luo Jiarui Ning Yingying Zhao Huangwei Wang Lixin Zhang Liyun Zhang State Key Laboratory of Medicinal Chemical Biology College of PharmacyNankai UniversityTianjin 300350China Max Planck Institute for Chemical Energy Conversion Stiftstrasse 34-3645470 Mülheim an der RuhrGermany State Key Laboratory of Medicinal Chemical Biology College of Life SciencesNankai UniversityTianjin 300350China State Key Laboratory of Bioreactor Engineering and School of BiotechnologyEast China University of Science and Technology(ECUST)Shanghai 200237China

Hydrogenase is a paradigm of highly efficient biocatalyst for H_(2) production and utilization evolved in nature. A dilemma is that despite the high activity and efficiency expected for hydrogenases as promising catalysts for the hydrogen economy, the poor oxygen tolerance and low yield of hydrogenases largely hinder their practical application. In these years, the enigmas surrounding hydrogenases regarding their structures, oxygen tolerance, mechanisms for catalysis, redox intermediates, and proton-coupled electron transfer schemes have been gradually elucidated;the schemes, which can well couple hydrogenases with other highly efficient(in)organic and biological catalysts to build novel reactors and drive valuable reactions, make it possible for hydrogenases to find their niches. To see how scientists put efforts to tackle this issue and design novel reactors in the fields where hydrogenases play crucial roles, in this review,recent advances were summarized, including different strategies for protecting enzyme molecules from oxygen, enzyme-based assembling systems for H_(2) evolution in the photoelectronic catalysis, enzymatic biofuel cells for H_(2) utilization and storage and the efficient electricity-hydrogen-carbohydrate cycle for high-purity hydrogen and biofuel automobiles. Limitations and future perspectives of hydrogenasebased applications in H_(2) production and utilization with great impact are discussed. In addition, this review also provides a new perspective on the use of biohydrogen in healthcare beyond energy.

关键词： Hydrogenase Biological H_(2)energy Oxygen tolerance Artificial photosynthesis Biofuel cells

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自走式精量榨菜直播机研制

拖拉机与农用运输车 2024年第4期51卷 44-47页

作者：刘川东张开赵立军杨斌罗航龚练重庆文理学院智能制造工程学院重庆402160 智能农业动力装备全国重点实验室河南洛阳471039 佳木斯大学黑龙江佳木斯154007

针对重庆市榨菜种植生产基本上还处在原始的传统栽培阶段,无论是早期青菜头栽培,还是榨菜原料生产,都是沿袭着全靠手工操作的播种育苗、本田移栽、施肥施药等繁重劳动生产方式,不但劳动强度大,而且种植成本较高。因此设计了一款适用于... 详细信息

针对重庆市榨菜种植生产基本上还处在原始的传统栽培阶段,无论是早期青菜头栽培,还是榨菜原料生产,都是沿袭着全靠手工操作的播种育苗、本田移栽、施肥施药等繁重劳动生产方式,不但劳动强度大,而且种植成本较高。因此设计了一款适用于重庆丘陵山地地区种植的自走式精量榨菜直播机,可以实现两行的精量播种,一次性完成开沟、滴灌、播种、施肥一系列的动作,经田间试验测试,各项指标满足行业标准要求。

关键词：青菜头丘陵山地地区榨菜直播机

Direct detection of a single[4Fe-4S]cluster in a tungsten-containing enzyme:Electrochemical conversion of CO_(2) into formate by formate dehydrogenase

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Carbon Energy 2023年第5期5卷 152-164页

作者： Wenjin Li Yanxin Gao Xuan Sun Lei Wan Haishuo Ji hang luo Yao Tian Hao Song Geng Wu Liyun Zhang State Key Laboratory of Medicinal Chemical Biology College of Life ScienceNankai UniversityTianjinPeople's Republic of China State Key Laboratory of Microbial Metabolism The Joint International Research Laboratory of Metabolic&Developmental SciencesSchool of Life Science and BiotechnologyShanghai Jiao Tong UniversityShanghaiPeople's Republic of China Max Planck Institute for Chemical Energy Conversion Mülheim an der RuhrGermany Frontier Science Center for Synthetic Biology Key Laboratory of Systems BioengineeringSchool of Chemical Engineering and TechnologyTianjin UniversityTianjinPeople's Republic of China

The conversion of CO_(2) into fuels and valuable chemicals is one of the central topics to combat climate change and meet the growing demand for renewable ***,we show that the formate dehydrogenase from Clostridium ljungdahlii(ClFDH)adsorbed on electrodes displays clear characteristic voltammetric signals that can be assigned to the reduction and oxidation potential of the[4Fe-4S]^(2+/+)cluster under nonturnover *** adding substrates,the signals transform into a specific redox center that engages in catalytic electron *** catalyzes rapid and efficient reversible interconversion between CO_(2) and formate in the presence of *** turnover frequency of electrochemical CO_(2) reduction is determined as 1210 s^(-1) at 25℃ and pH 7.0,which can be further enhanced up to 1786 s^(-1) at 50℃.The Faradaic efficiency at−0.6 V(*** hydrogen electrode)is recorded as 99.3%in a 2-h *** experiments and theoretical modeling disclose interesting pathways for CO_(2) entry,formate exit,and OCN−competition,suggesting an oxidation-state-dependent binding mechanism of *** results provide a different perspective for understanding the catalytic mechanism of FDH and original insights into the design of synthetic catalysts.

关键词： bioelectrocatalysis biofuel CO_(2)conversion formate dehydrogenase iron-sulfur cluster

饮食中黄酮类化合物摄入量与人体总骨矿物质含量的关联性分析

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现代预防医学 2024年第3期51卷 433-438页

作者：马国琛胡一凡字璟李昊奇曾雅贤罗航徐珏熊静远四川大学华西公共卫生学院/华西第四医院

目的探讨饮食中黄酮类化合物的摄入与人体总骨矿物质含量之间的关系。方法选择2017—2018年美国国家健康和营养调查(NHANES)中20～59岁成年人作为研究对象，通过构建多变量线性回归模型，对性别、年龄、种族、受教育水平、婚姻状况、... 详细信息

目的探讨饮食中黄酮类化合物的摄入与人体总骨矿物质含量之间的关系。方法选择2017—2018年美国国家健康和营养调查(NHANES)中20～59岁成年人作为研究对象，通过构建多变量线性回归模型，对性别、年龄、种族、受教育水平、婚姻状况、经济情况、BMI、饮酒情况、高血压、糖尿病及心血管疾病进行调整，探究饮食中黄酮类化合物摄入量和人体总骨矿物质含量之间的关系。结果研究共纳入2 110人，男女比例约为1:1，平均总矿物质含量为2 341.4 g，饮食中总黄酮摄入量的中位数为74.45 mg。在调整了性别、年龄、种族、受教育水平、婚姻状况、经济情况、BMI、饮酒情况、高血压、糖尿病和心血管疾病后的线性回归模型显示全身总骨矿物质含量与饮食中异黄酮摄入量呈正相关(β=0.68,95%CI:0.26～1.09)，并存在剂量反应关系(Ptrend=0.001)，此外，亚组分析结果表明，该正相关关系在男性中更为强烈[男性(β=1.39, 95%CI:0.67～2.11)vs.女性(β=0.18, 95%CI:-0.31～0.67), Pinter=0.038]。结论饮食中异黄酮摄入可能会增加人体全身总骨矿物质的含量，但是否具有性别差异仍需进一步探究。

关键词：黄酮类化合物异黄酮总骨矿物质含量

Improved dielectric constant and energy density of P(VDF-HFP)composites using NBT-xST(x=0,0.10,0.26)whiskers

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Journal of Advanced Dielectrics 2018年第6期8卷 80-88页

作者： Xuefan Zhou Lu Wang Guoliang Xue Kechao Zhou hang luo Dou Zhangy State Key Laboratory of Powder Metallurgy Central South University Changsha Hunan 410083P.R.China

The high-performance energy-storage dielectric capacitors are increasingly important due to their wide applications in high power ***,we fabricated a novel P(VDF-HFP)-based capacitor with surface-modified NBT-xST(x?0,0.10,0.26)whiskers,denoted as Dop@NBT-xST/P(VDF-HFP).The influences of ST content,fillers’volume fraction and electric field on the dielectric properties and energy-storage performance of the composites were investigated *** results show that the dielectric constant monotonously increased with the increase of ST content and fillers’volume *** composite containing 10.0 vol%NBT-0.26STwhiskers possessed a dielectric constant of 39 at 1 kHz,which was 5.6 times higher than that of pure P(VDF-HFP).It was noticed that the D-E loops of the composites became thinner and thinner with the increase of ST *** to the reduced remnant polarization,the composite with 5.0 vol%NBT-0.26STwhiskers achieved a high energy density of 6.18 J/cm3 and energy efficiency of approximately 57%at a relatively low electric field of 200 kV/*** work indicated that NBT-0.26ST whisker is a kind of potential ceramic filler in fabricating the dielectric capacitor with high discharged energy density and energy efficiency.

关键词： P(VDF-HFP) NBT-xST whiskers dielectric composite dielectric constant energy storage

基于OBE理念的高职药学专业课程诊断及改进研究

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卫生职业教育 2024年第8期42卷 53-56页

作者：李玉婷黄仕芳唐云周振华骆航永州职业技术学院湖南永州425006

通过分析高职药学专业课程体系现状及存在的问题,以OBE(成果导向教育)理念为理论指导,从完善课程质量保证体系、形成课程目标链、制订课程质量控制标准方面构建高职药学专业课程诊改模式,形成基于OBE理念的课程诊改循环,有效促进技术技... 详细信息

通过分析高职药学专业课程体系现状及存在的问题,以OBE(成果导向教育)理念为理论指导,从完善课程质量保证体系、形成课程目标链、制订课程质量控制标准方面构建高职药学专业课程诊改模式,形成基于OBE理念的课程诊改循环,有效促进技术技能人才培养质量持续提升。

关键词： OBE 高职药学专业课程诊改

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