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Fast saccharide mapping method for quality consistency evaluation of commercial xylooligosaccharides collected in China

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Journal of Pharmaceutical Analysis 2021年第3期11卷 284-291页

作者： Yong deng Cunwu Chen Lingxiao Chen Bangxing Han Shaoping Li Jing Zhao State Key Laboratory of Quality Research in Chinese Medicine Institute of Chinese Medical SciencesUniversity of MacaoMacaoChina Anhui Engineering Laboratory for Conservation and Sustainable Utilization of Traditional Chinese Medicine Resources West Anhui UniversityLu'anAnhuiChina

Due to the extensive use of xylooligosaccharides(XOS)as functional food ingredients,many inferior goods and even adulterants are generally found in the market,which may pose a health hazard to certain *** method such as high-performance liquid chromatography(HPLC)and high-performance thin-layer chromatography(HPTLC)is traditionally applied for the quality analysis of ***,it is time consuming due to the prolonged separation and pre-or post-derivatization *** this study,a fast saccharide mapping method based on matrix-assisted laser desorption/time-of-flight mass spectrometry(MALDI-TOF-MS)was developed for the quality consistency analysis of 22 batches of XOS collected from different manufacturers in *** time needed for saccharides analysis using MALDI-MS was less than 30 min for one plate,at least 6 times faster than that by the traditional HPTLC chromatography *** addition,MALDI-MS possessed higher resolution for XOS with DP4-DP7 based on the difference of m/z,which is hardly separated using *** results showed that XOS were present only in samples XY01-XY11,samples XY12-XY14 only consisted of hex oligosaccharides,and samples XY15-XY22 were free of *** indicate that the quality consistency of XOS products in the China market was poor,which should be carefully investigated.

关键词： Xylooligosaccharides Saccharide mapping MALDI-MS Quality control

Optimal mining sequence for coal faces under a bedding slope:insight from landslide prevention

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Journal of Mountain Science 2024年第5期21卷 1775-1798页

作者： LI Qingmiao ZHAO Jianjun LI Zhichao deng Jie ZUO Jing LAI Qiyi State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of TechnologyChengdu 610059China

Repetitive mining beneath bedding slopes is identified as a critical factor in geomorphic disturbances, especially landslides and surface subsidence. Prior research has largely concentrated on surface deformation in plains due to multi-seam coal mining and the instability of natural bedding slopes, yet the cumulative impact of different mining sequences on bedding slopes has been less explored. This study combines drone surveys and geological data to construct a comprehensive three-dimensional model of bedding slopes. Utilizing FLAC3D and PFC2D models, derived from laboratory experiments, it simulates stress, deformation, and failure dynamics of slopes under various mining sequences. Incorporating fractal dimension analysis, the research evaluates the stability of slopes in relation to different mining sequences. The findings reveal that mining in an upslope direction minimizes disruption to overlying strata. Initiating extraction from lower segments increases tensile-shear stress in coal pillar overburdens, resulting in greater creep deformation towards the downslope than when starting from upper segments, potentially leading to localized landslides and widespread creep deformation in mined-out areas. The downslope upward mining sequence exhibits the least fractal dimensions, indicating minimal disturbance to both strata and surface. While all five mining scenarios maintain good slope stability under normal conditions, recalibrated stability assessments based on fractal dimensions suggest that downslope upward mining offers the highest stability under rainfall, contrasting with the lower stability and potential instability risks of upslope downward mining. These insights are pivotal for mining operations and geological hazard mitigation in multi-seam coal exploitation on bedding slopes.

关键词： Bedding rock landslides Mining-induced deformation Bedding slope stability Underground mining sequences Fractal-based strength reduction method

Design and Experiment of a Deformable Bird-inspired UAV Perching Mechanism

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Journal of Bionic Engineering 2021年第6期18卷 1304-1316页

作者： Long Bai Hao Wang Xiaohong Chen Jia Zheng Liming Xin Yupeng deng Yuanxi Sun State Key Laboratory of Mechanical Transmission Chongqing UniversityChongqing400030China College of Advanced Manufacturing Engineering Chongqing University of Posts and TelecommunicationsChongqing400065China School of Computer Engineering and Science Shanghai UniversityShanghai200444China

Energy consumption and acoustic noise can be significantly reduced through perching in the sustained flights of small Unmanned Aerial Vehicles(UAVs).However,the existing flying perching robots lack good adaptability or loading capacity in unstructured *** at solving these problems,a deformable UAV perching mechanism with strong adaptability and high loading capacity,which is inspired by the structure and movements of birds'feet,is presented in this *** elastic toes,an inverted crank slider mechanism used to realize the opening and closing movements,and a gear mechanism used to deform between two configurations are included in this *** experiments on its performance towards different objects,Results show that it can perch on various objects reliably,and its payload is more than 15 times its *** integrating it with a quadcopter,it can perch on different types of targets in outdoor environments,such as tree branches,cables,eaves,and spherical *** addition,the energy consumption of the UAV perching system when perching on objects can be reduced to 0.015 times that of hovering.

关键词： Perching mechanism Bionic design UAV Flying robot Grasper

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西方传教士眼中的羌族神灵信仰

贵州民族研究 2006年第5期26卷 133-139页

作者：邓宏烈四川大学政治学院四川成都610064

19世纪晚期到20世纪初期,基督教在羌族中的传播可谓基督教在华传播事业中的一颗流星。它留给人们的思考是多方面的。其中,基督福音的“圣灵”与羌族原始宗教的“神灵”相遇。于是,福音传播者捧着福音书,按照各自的宗教文化价值取向和经... 详细信息

19世纪晚期到20世纪初期,基督教在羌族中的传播可谓基督教在华传播事业中的一颗流星。它留给人们的思考是多方面的。其中,基督福音的“圣灵”与羌族原始宗教的“神灵”相遇。于是,福音传播者捧着福音书,按照各自的宗教文化价值取向和经验认知,对羌族原始宗教的神灵信仰做出不同的阐释。

关键词：基督教圣灵观传教士羌族宗教神灵信仰

听觉的现代性:以法商东方百代公司唱片出版为个案的研究(1908-1930)

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编辑之友 2017年第3期 93-98页

作者：贾登红南京大学历史学院

唱片作为我国近代史上最早的“音像出版物”，甫一出现，便通过“听觉书写”改变了中国人对声音的“知”与“听”，推动了“声音”作为一种知识性、娱乐性、消费性题材的大众化与日常化。民国较早出现的法商东方百代唱片公司，前后共出... 详细信息

唱片作为我国近代史上最早的“音像出版物”，甫一出现，便通过“听觉书写”改变了中国人对声音的“知”与“听”，推动了“声音”作为一种知识性、娱乐性、消费性题材的大众化与日常化。民国较早出现的法商东方百代唱片公司，前后共出版唱片三千余种，对我国近代唱片出版业有着不可忽视的影响与推动作用。以其为个案，从它影响下的“听觉书写”“听觉下的生活”“听觉与技术”等方面进行研究与梳理，有助于探索技术发展与出版企业、出版物及社会文化变迁之间的互动关系，进而认知当下音像出版物发展。

关键词：东方百代公司唱片听觉出版技术

中美三高校小学教育专业本科培养方案的比较研究

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比较教育研究 2014年第8期36卷 31-36页

作者：邓艳红首都师范大学初等教育学院北京100048

通过对在国内享有盛誉的首都师范大学小学教育专业与在美国排名前列的公立的威斯康辛大学麦迪逊分校小教专业以及私立的范德堡大学小教专业三校本科培养方案的比较发现,在专业方向设置、培养目标、课程方案和培养过程等方面,三校有一些... 详细信息

通过对在国内享有盛誉的首都师范大学小学教育专业与在美国排名前列的公立的威斯康辛大学麦迪逊分校小教专业以及私立的范德堡大学小教专业三校本科培养方案的比较发现,在专业方向设置、培养目标、课程方案和培养过程等方面,三校有一些共同特点,也有许多各自特色,尤其是美国两校的专业方向设置的多视角、培养目标的集中化、课程的整合化和培养过程的严格监控等成熟经验值得我国借鉴。

关键词：小学教育专业本科培养方案中美比较研究

基于参数优化SVM方法识别盐生植被钠离子光谱特征

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光谱学与光谱分析 2020年第1期40卷 247-254页

作者：邓来飞张飞齐亚霄袁婕新疆大学资源与环境科学学院智慧城市与环境建模自治区普通高校重点实验室新疆乌鲁木齐830046 新疆大学绿洲生态教育部重点实验室新疆乌鲁木齐830046 中亚地理信息开发利用国家测绘地理信息局工程技术研究中心新疆乌鲁木齐830002

新疆盐渍土地分布广、面积大,在这些盐渍土地上生长着多种类型的盐生植物,它们对改良盐渍土地、维护生态稳定、促进生态平衡具有重要的现实意义。有关研究表明,许多盐土植物大量吸收钠,钠与钾都能增加细胞渗透压,以适应高盐环境,产生膨... 详细信息

新疆盐渍土地分布广、面积大,在这些盐渍土地上生长着多种类型的盐生植物,它们对改良盐渍土地、维护生态稳定、促进生态平衡具有重要的现实意义。有关研究表明,许多盐土植物大量吸收钠,钠与钾都能增加细胞渗透压,以适应高盐环境,产生膨压而促进细胞的伸长,因而对其生长是有益的,能部分代替钾的功能。因此掌握盐生植物的钠特征,有助于了解盐生植物对生态环境的长期适应和响应,使用高光谱技术实现有效诊断叶片钠特征。首先,对实测冠层高光谱数据,采用离散小波变换(DWT)和db5小波对原始光谱进行9层小波分解,求取最佳分解层数为5层。其次,对光谱数据进行5层db5小波分解,对分解后的高频分量和低频分量建立了小波植被指数,筛选出可敏感表征钠离子含量的小波植被指数。最后,利用SVR, LS-SVR, PSO-SVR和PSO-LS-SVR模型建立盐生植被钠离子含量的估算模型,并与由原始光谱构建的光谱植被指数建立的估算模型进行比较。此外,引入偏最小二乘回归模型PLSR作为对比,评价参数优化的支持向量机方法在高光谱技术估测盐生植被叶片钠离子含量的优势。结果表明:(1)5种模型预测结果表明, PSO能有效优化SVR和LS-SVR模型参数(c,g),提高模型精度和预测能力,优化后的模型具有预测精度高、泛化能力强以及稳健性能好等特点。(2)综合小波指数构建的模型是综合多尺度、多分辨率数据的反演模型,其能从不同侧面反映植被的信息,因而综合小波指数构建的4种模型优于单一小波指数构建的模型。(3)对比两种类型的植被指数反演结果,单一小波植被指数构建Na^+含量的预测模型可取得较好的预测效果,单一光谱指数估测Na^+含量效果不佳,这是因为小波变换可以减少原始光谱的噪声,凸显光谱的细节信息,增强其反演Na^+含量的精度;综合小波植被指数构建的模型精度和预测效果优于综合光谱指数构建的模型,原始光谱经小波变换后,可凸显更多的细节信息,提高高光谱反演叶片Na^+含量的能力。

关键词：盐生植被钠离子高光谱小波变换支持向量机

Construction and Properties of Simvastatin and Calcium Phosphate Dual-Loaded Coaxial Fibrous Membranes with Osteogenic and Angiogenic Functions

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Journal of Bionic Engineering 2022年第6期19卷 1645-1657页

作者： Chang Liu Dan deng Jing Gao Shue Jin Yi Zuo Yubao Li Jidong Li Research Center for Nano-Biomaterials Analytical&Testing CenterSichuan UniversityChengdu610064China

The ideal Guided Bone Regeneration(GBR)membrane is required to have good biocompatibility,space maintenance ability,appropriate degradation rate,and preferably can guide the regeneration of vascularized bone *** this study,Simvastatin(SIM)and calcium Phosphate(CaP)were encapsulated in a Polycaprolactone(PCL)/Chitosan(CS)core-shell structural fibrous membranes via coaxial electrospinning *** results showed that loaded SIM in the core of the core-shell structure fibrous membranes could sustainably release the drug for more than two months and upregulate the angiogenic marker of Bone Mesenchymal Stem Cells(BMSCs).Adding a certain amount of CaP to the shell layer provided more sites for the mineralization and synergistic with SIM to promote osteogenic differentiation of BMSCs in *** intramuscular implantation experiments in rabbits suggested a normal early inflammation and enhanced vascularization induced by the SIM-loaded fibrous *** study proposed an effective strategy to prepare a dual-loaded core-shell fibrous membrane for guided vascularized bone tissue regeneration.

关键词： Simvastatin Calcium phosphate Coaxial electrospinning Vascularization Guided Bone Regeneration

Cs_(3)Bi_(2)B_(9)/BiOBr S-scheme heterojunction for selective oxidation of benzylic C-H bonds

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Journal of Materials Science & Technology 2024年第13期180卷 150-159页

作者： Jie deng Difa Xu Jinfeng Zhang Quanlong Xu Yun yang Zhiyi Wei Zhi Su Wenzhou Key Lab of Advanced Energy Storage and Conversion Zhejiang Province Key Lab of Leather EngineeringCollege of Chemistry and Materials EngineeringWenzhou UniversityWenzhou 325027China Hunan Key Laboratory of Applied Environmental Photocatalysis Changsha UniversityChangsha 410022China Anhui Key Laboratory of Energetic Materials College of Physics and Electronic InformationHuaibei Normal UniversityHuaibei 235000China School of Energy and Chemical Engineering Xinjiang Institute of TechnologyAkesu 843100China

Converting hydrocarbons into aldehydes in a green and environmentally benign way is of great signif-icance in fine *** this work,all-inorganic Cs_(3)Bi_(2)B_(9) perovskite nanoparticles were uniformly loaded on BiOBr nanosheets via an in-situ growth method,which can selectivity photoactivate aromatic C(sp^(3))-H bond of toluene to generate *** to the in-situ X-ray photoelectron spec-troscopy characterization,the photogenerated electrons of BiOBr transfer to Cs_(3)Bi_(2)B_(9) enforced by the in-ternal electric field under light irradiation,resulting in S-scheme ***,theoretical calculations indicate that toluene molecules are inclined to adsorb on the BiOBr surface,subsequently in-volving the oxidation reaction to generate benzyl radical(PhCH_(2)·)by using the energetic holes of BiOBr,while the remaining photoinduced electrons in the conduction band(CB)of Cs_(3)Bi_(2)B_(9) with powerful reduction ability reduce O2 into·O_(2)^(-),which is the vital oxidative active species working on toluene selective oxidation *** an unexceptionable charge carrier utilization mode and tendentious ad-sorption behavior of reactants contribute to the optimized Cs_(3)Bi_(2)B_(9)/BiOBr heterojunction with excellent photocatalytic performance,achieving a maximum of 22.5%toluene conversion and 96.2%selectivity to-wards benzaldehyde *** work provides a rational photocatalyst heterojunction construction protocol for the selective oxidation of saturated aromatic C-H bonds.

关键词： Cs_(3)Bi_(2)Br_(9)/BiOBr C(sp^(3))–H activation S-scheme heterojunction Selective organic synthesis Photocatalysis