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Denatured proteins show new vitality:Green synthesis of germanium oxide hollow microspheres with versatile functions by denaturing proteins around bubbles

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聚集体(英文)

聚集体(英文) 2023年第1期4卷 238-249页

作者： Yanfang Zhao Xin Liang Daoyuan Chen xuhui bian Wanjian Liu Lei Han College of Chemistry and Pharmaceutical Sciences Qingdao Agricultural UniversityQingdaoShandongChina Qingdao Shuojing Biological Technology Co. Ltd.QingdaoShandongChina

The hollow structure has long attracted great attention because of its excellent ***,this special structure is usually synthesized through some complex ***,we discovered that denatured bovine serum albumin(BSA)can trigger unusual biomineralization for the simple,green and shape-controllable synthesis of germanium oxide(GeOx)hollow microsphere(HMS).At high temperature(60℃),BSA was denatured,and a compact BSA layer was formed around the H2 *** denatured BSA layer was stable and suitable for anchoring and growing *** simply changing the BSA concentration and temperature,various morphologies of GeOx could be *** to the denatured protein skeletons and microenvironment-regulated collapse,GeOx HMS showed great potential for intelligently responsive pesticide delivery in the insect gut,showing superiority over traditional delivery systems,which early release pesticides in the mouth and *** by its large specific surface area,excellent biocompatibility,modifiable functional groups,and high electrocatalytic activity,GeOx HMS was also applied to versatile sensors for H_(2)O_(2) assays at physiological pH and rapid coronavirus COVID-19 *** work not only provides some evidence for understanding proteins in depth but also paves a new avenue for the biomineralization-inspired synthesis of hollow structures with versatile functions.

关键词： biomineralization COVID-19 denatured protein electrochemical sensor hollow microsphere intelligent pesticide delivery

基于灰关联理论的玄武岩纤维混凝土孔与抗冻性能相关性研究

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中外公路 2022年第4期42卷 192-198页

作者：边旭辉申爱琴连城吴华李悦陕西省高速公路建设集团公司古镇高速公路建设管理处陕西汉中723500 长安大学特殊地区公路工程教育部重点实验室陕西西安710064

为探究玄武岩纤维的掺入对混凝土抗冻性能的微观孔结构改善机理,制备6种不同纤维长度、掺量的玄武岩纤维混凝土并对其进行抗冻试验和压汞试验。结果表明:玄武岩纤维能有效改善混凝土由于冻融循环造成的表面及内部损伤,掺入12 mm、0.06%... 详细信息

为探究玄武岩纤维的掺入对混凝土抗冻性能的微观孔结构改善机理,制备6种不同纤维长度、掺量的玄武岩纤维混凝土并对其进行抗冻试验和压汞试验。结果表明:玄武岩纤维能有效改善混凝土由于冻融循环造成的表面及内部损伤,掺入12 mm、0.06%的玄武岩纤维混凝土的质量损失率及抗弯拉强度损失率较基准混凝土分别降低73.9%及26.4%。玄武岩能显著优化混凝土内部孔结构,降低其平均孔径及有害孔比例。同时,基于灰关联理论确定了与抗弯拉强度、相对弹性模量灰色关联度最高的孔结构参数,即多害孔比例。最后采用多元非线性回归分析分别建立玄武岩纤维混凝土抗弯拉强度-孔参数、相对弹性模量-孔参数的数学模型。

关键词：玄武岩纤维路面混凝土冻融循环灰色关联度多元非线性回归

Influence of Intermittent Turbulence on Air Pollution and Its Dispersion in Winter 2016/2017 over Beijing, China

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Journal of Meteorological Research 2020年第1期34卷 176-188页

作者： Wei WEI Hongsheng ZHANG xuhui CAI Yu SONG Yuxuan bian Kaitao XIAO He ZHANG State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesChina Meteorological AdministrationBeijing 100081 Laboratory for Climate and Ocean–Atmosphere Studies Department of Atmospheric and Oceanic SciencesSchool of PhysicsPeking UniversityBeijing 100871 State Key Joint Laboratory of Environmental Simulation and Pollution Control Department of Environmental SciencePeking UniversityBeijing 100871 State Key Laboratory of NBC Protection for Civilian Beijing 102205

With rapid urbanization in recent years,severe air pollution has emerged as a major issue for many regions of China,especially in some metropolises.A persistent pollution case during 6 December 2016–8 January 2017 was selected to investigate the relations between turbulent intermittency and frequent PM2.5(particulate matters with diameter less than 2.5μm)pollution events over the metropolitan region of Beijing,*** accumulation of PM2.5 near the surface frequently occurred as a combined result of strong inversion layers,stagnant winds,high ambient humidity levels,and stable stratification during this ***-order Hilbert spectral analysis indicated that steep decreases in the PM2.5 concentration were simultaneous with the occurrence of intermittent turbulence and strong vertical mixing.A wind profiler observation revealed existence of low-level jets(LLJs)at the end of the polluted periods,suggesting that the upper-level turbulent mixing accompanied by the wind shear of LLJ was transported downward and enhanced the vertical mixing near the surface,which might have caused an abrupt reduction in PM2.5 and improvement in air conditions.

关键词： intermittent turbulence PM2.5 stable stratification Beijing

Sign series entropy analysis of short-term heart rate variability

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Chinese Science Bulletin 2009年第24期54卷 4610-4615页

作者： bian ChunHua MA QianLi SI JunFeng WU xuhui SHAO Jun NING XinBao WANG DongJin Key Laboratory of Modern Acoustics Institute for Biomedical Electronic Engineering Department of Electronic Science and Engi- neering Nanjing University Nanjing 210093 China College of Geography and Biological Information Nanjing University of Posts and Telecommunications Nanjing 210003 China The Affiliated Drumtower Hospital of Nanjing University Medical School Nanjing 210008 China

Complexity and nonlinearity approaches can be used to study the temporal and structural order in heart rate variability (HRV) signal, which is helpful for understanding the underlying rule and physiological essence of cardiovascular regulation. For clinical applications, methods suitable for short-term HRV analysis are more valuable. In this paper, sign series entropy analysis (SSEA) is proposed to characterize the feature of direction variation of HRV. The results show that SSEA method can detect sensitively physiological and pathological changes from short-term HRV signals, and the method also shows its robustness to nonstationarity and noise. Thus, it is suggested as an efficient way for the analysis of clinical HRV and other complex physiological signals.

关键词：心率变异性变异性分析熵分析短期临床应用抗原检测非线性方法心血管调节

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车用电驱系统主动短路模型及参数设计

中国电机工程学报 2022年第8期42卷 3013-3022页

作者：边元均温旭辉范涛国敬孟柳中国科学院大学北京市海淀区100049 中国科学院电工研究所北京市海淀区100190

在电动汽车用永磁同步电机驱动系统中,常采用主动短路(active short circuit,ASC)的方法避免高速行驶条件下电机反电动势过高造成的动力电池损坏。该方法存在交流侧暂态电流峰值较大,易造成功率器件过流损坏的缺点。考虑线性变调制比型... 详细信息

在电动汽车用永磁同步电机驱动系统中,常采用主动短路(active short circuit,ASC)的方法避免高速行驶条件下电机反电动势过高造成的动力电池损坏。该方法存在交流侧暂态电流峰值较大,易造成功率器件过流损坏的缺点。考虑线性变调制比型主动短路(linear variable modulation ratio active short circuit,LVM-ASC)能有效降低暂态电流峰值而尚无机理模型提出。该文对ASC方法下的电机最大峰值电流进行定量分析,通过分段线性化建立系统在LVM-ASC方法下的离散化电流模型,并给出一种变调制比时间参数的设计方法,提升主动短路保护策略的灵活性。最后通过仿真和实验验证模型和参数设计方法的有效性。

关键词：主动短路离散时间法电动汽车参数设计

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永磁同步电机高性能电流预测控制

电工技术学报 2022年第17期37卷 4335-4345页

作者：章回炫范涛边元均温旭辉孙鸿雁中国科学院电工研究所北京100190 中国科学院大学北京100049

高性能永磁同步电机控制系统对电流环的动态性能要求很高,传统的PI控制带宽有限,且易出现超调等现象,基于电流预测的无差拍控制具有较好的动态响应。为此,提出了一种在同步旋转轴系下改进时序的电流预测无差拍控制算法。通过对传统电流... 详细信息

高性能永磁同步电机控制系统对电流环的动态性能要求很高,传统的PI控制带宽有限,且易出现超调等现象,基于电流预测的无差拍控制具有较好的动态响应。为此,提出了一种在同步旋转轴系下改进时序的电流预测无差拍控制算法。通过对传统电流预测无差拍控制的时序分析,电流控制器对电流指令进行分段采样,基于永磁同步电机交直轴电压方程模型得到电压指令的补偿值,消除了原有电流指令滞后一拍的计算延时。同时,分析功率器件非理想因素与延时效应对电压状态量产生的偏差,引入电压重构算法,减小状态量误差对电流跟踪精度的影响。仿真和实验结果表明,与传统无差拍电流预测控制相比,改进后的电流预测控制算法有效地提高了电流环的动态性能和稳态精度。

关键词：永磁同步电机电流预测无差拍控制时序优化电压重构

Surface modification of titanium dioxide for electrophoretic particles

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Frontiers of Chemical Science and Engineering 2007年第4期1卷 338-342页

作者： PENG xuhui LE Yuan bian Shuguang LI Woyuan WU Wei DAI Haitao CHEN Jianfeng Key Lab for Nanomaterials Ministry of EducationBeijing University of Chemical TechnologyBeijing 100029China

To prepare stable electrophoretic ink(E Ink)needs color particles to be uniformly dispersed in the organic ***,t-he modification of inorganic particle surface is *** this paper,Titanium dioxide modified by alumina has been *** surface composition and struc-tures of modified particles have been characterized by X-ray photoelectron spectrometer(XPS),X-ray diffractometer(XRD)and Fourier transform infrared spectrometer(FT-IR).The dispersibility and electrophoretic mobility of these particles in tetrachloroethylene(TCE)have been investigated by laser particle size analyzer,static sedimentation and elec-trophoretic *** of temperature,pH value and stirring rate on the dispersibility and the charge property of samples have been *** results indicate the settle time of modified TiO2 can last 120 h with the response time of 35 s under the optimized modifying conditions,in which temperature is 85℃-90℃,pH is 8-9 and stirring rate is 800 r·min^(−1).The dispersibility and electrophoretic mobility have been significantly improved,which means that the modified TiO2 is suitable for electrophoretic ink particles.

关键词： titanium dioxide surface modification dispersibility electrophoretic mobility

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高性能永磁同步发电机无位置传感器控制策略

兵工学报 2022年第11期43卷 2761-2772页

作者：刘忠永国敬范涛边元均孟柳章回炫温旭辉中国科学院大学北京100049 中国科学院电工研究所北京100190

为提高全电化军用特种车辆的可靠性,进一步提升车载发电系统的功率密度,提出一种全速度范围内的永磁同步发电机无位置传感器控制策略。发电系统采用电压、电流双闭环的矢量控制算法,根据转速划分工作区,在低速区内,通过基于正交锁相环... 详细信息

为提高全电化军用特种车辆的可靠性,进一步提升车载发电系统的功率密度,提出一种全速度范围内的永磁同步发电机无位置传感器控制策略。发电系统采用电压、电流双闭环的矢量控制算法,根据转速划分工作区,在低速区内,通过基于正交锁相环的角度跟踪器获取转子位置信息,在中高速工作区内,基于线性状态观测器实现转子位置估算,并结合基于递推最小二乘法的参数辨识算法,向观测器实时更新不同工况下的电机参数,以保证无位置算法的鲁棒性。仿真和实验结果表明:该控制策略在全速度范围内皆能实现精准的转子位置观测,电机状态在工作区切换处过渡平滑,负载投切时系统响应快速稳定,保证了特种车辆发电系统运行的可靠性。

关键词：永磁同步发电机无位置传感器状态观测器锁相环参数辨识

A high power factor fault-tolerant vernier permanent-magnet machine

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A high power factor fault-tolerant vernier permanent-magnet ...