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一种应用于音频的可重构Σ-Δ连续时间调制器

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微电子学 2024年第2期54卷 183-188页

作者：罗育豪韦保林岳宏卫桂林电子科技大学广西精密导航技术与应用重点实验室广西桂林541004

基于180 nm CMOS工艺,设计了一种应用于音频领域的可重构前馈式3阶Σ-Δ连续时间调制器。传统Σ-Δ连续时间调制器只有一种工作模式,而该设计利用可重构的积分器使Σ-Δ连续时间调制器具有高精度和低功耗两种工作模式。此外,采用的加法... 详细信息

基于180 nm CMOS工艺,设计了一种应用于音频领域的可重构前馈式3阶Σ-Δ连续时间调制器。传统Σ-Δ连续时间调制器只有一种工作模式,而该设计利用可重构的积分器使Σ-Δ连续时间调制器具有高精度和低功耗两种工作模式。此外,采用的加法器提前技术减小了调制器功耗,负电阻补偿技术提高了调制器的SNDR,额外环路延时补偿技术提高了调制器的稳定性。仿真结果表明,在20 kHz信号带宽、1.8 V电源电压下,低功耗模式下调制器的SNDR为94.7 dB,功耗为291μw;高精度模式下调制器的SNDR为108 dB,功耗为436.6μw。

关键词：连续时间可重构 Σ-Δ调制器高精度

基于低场核磁共振技术进行黄酒发酵进程监测及品牌的分析

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食品与发酵工业 2024年第4期50卷 279-285页

作者：王欣郑思宇冯龙斐刘敏刘宝林上海理工大学健康科学与工程学院上海200093

该文对不同发酵阶段的黄酒样品进行低场核磁共振(low-field nuclear magnetic resonance,LF-NMR)检测,比较了陈酿时间、酒精度和品牌对黄酒低场核磁弛豫特性的影响,最后对9个品牌黄酒的LF-NMR弛豫信息进行了主成分分析。结果表明,发酵... 详细信息

该文对不同发酵阶段的黄酒样品进行低场核磁共振(low-field nuclear magnetic resonance,LF-NMR)检测,比较了陈酿时间、酒精度和品牌对黄酒低场核磁弛豫特性的影响,最后对9个品牌黄酒的LF-NMR弛豫信息进行了主成分分析。结果表明,发酵后样品的单组分弛豫时间(T_(2w))显著缩短,而陈酿后黄酒的T_(2w)又相对延长。多组分弛豫图谱(T_(2))表明,对照组和浸米样品均只有1个峰。发酵后样品的T_(2)图谱均出现2个峰。从第一次发酵到煎酒期间,T_(21)和T_(22)不断缩短,而陈酿期间T_(21)和T_(22)相对延长。同一品牌及陈酿时间的黄酒,酒精度越大,体系的T_(2w),T_(21)和T_(22)越短;同一品牌及酒精度下,陈酿时间仅对T_(21)有一定影响。不同品牌黄酒因酿造工艺的区别而使弛豫分布有一定特点。主成分分析表明,不同酒精度、陈酿时间、品牌及种类的黄酒的弛豫特性的PCA分布及间距不同。说明应用LF-NMR技术可实现对不同工艺生产的黄酒的快速辨别。

关键词：黄酒低场核磁共振发酵品牌

长春大气细颗粒物中多环芳烃的季节变化及健康风险评价

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环境污染与防治 2024年第2期46卷 226-232页

作者：赵东洋安淼刘宝林于泳辽宁工程技术大学环境科学与工程学院辽宁阜新123000 中国科学院湿地生态与环境重点实验室中国科学院东北地理与农业生态研究所吉林长春130102 长春师范大学化学学院吉林长春130032

为研究长春大气细颗粒物(PM_(2.5))中多环芳烃(PAHs)的季节变化及健康风险评价,于2020年9月至2021年4月采集大气PM_(2.5)样品,测定PM_(2.5)中16种优先控制PAHs的浓度。结果表明,除二苯并(a,h)蒽外,其他15种PAHs均有检出,总质量浓度在0~1... 详细信息

为研究长春大气细颗粒物(PM_(2.5))中多环芳烃(PAHs)的季节变化及健康风险评价,于2020年9月至2021年4月采集大气PM_(2.5)样品,测定PM_(2.5)中16种优先控制PAHs的浓度。结果表明,除二苯并(a,h)蒽外,其他15种PAHs均有检出,总质量浓度在0~198.00 ng/m^(3),平均值为67.80 ng/m^(3),呈冬季(平均值71.90 ng/m^(3))>春季(平均值70.50 ng/m^(3))>秋季(平均值55.20 ng/m^(3))的特征,PAHs的苯并(a)芘毒性当量季节变化明显,冬季(平均值4.40 ng/m^(3))显著高于秋季(平均值1.26 ng/m^(3))和春季(平均值0.38 ng/m^(3))。成人和儿童在冬季的平均终生致癌风险(ILCR)值分别为2.15×10^(-5)、2.43×10^(-5),显著高于秋季(成人6.18×10^(-6)、儿童6.98×10^(-6))和春季(成人1.84×10^(-6)、儿童2.08×10^(-6)),冬季大气PM_(2.5)中PAHs可能对人体存在一定致癌风险。

关键词：大气颗粒物多环芳烃季节变化健康风险评价

Synthetic biodegradable functional polymers for tissue engineering:a brief review

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Science China Chemistry 2014年第4期57卷 490-500页

作者： GUO baolin MA Peter X Center for Biomedical Engineering and Regenerative Medicine Frontier Institute of Science and Technology Xi'an Jiaotong University Department of Biomedical Engineering University of Michigan Department of Biologic and Materials Sciences University of Michigan Macromolecular Science and Engineering Center University of Michigan Department of Materials Science and Engineering University of Michigan

Scaffolds play a crucial role in tissue engineering. Biodegradable polymers with great processing flexibility are the predominant scaffolding materials. Synthetic biodegradable polymers with well-defined structure and without immunological concerns associated with naturally derived polymers are widely used in tissue engineering. The synthetic biodegradable polymers that are widely used in tissue engineering, including polyesters, polyanhydrides, polyphosphazenes, polyurethane, and poly(glycerol sebacate) are summarized in this article. New developments in conducting polymers, photoresponsive polymers, amino-acid-based polymers, enzymatically degradable polymers, and peptide-activated polymers are also discussed. In addition to chemical functionalization, the scaffold designs that mimic the nano and micro features of the extracellular matrix(ECM) are presented as well, and composite and nanocomposite scaffolds are also reviewed.

关键词： synthetic biodegradable polymers functional polymers scaffolds tissue engineering

同位素内标-超高效液相色谱-串联质谱技术同时检测新鲜银耳中米酵菌酸和异米酵菌酸

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分析科学学报 2024年第1期40卷 88-93页

作者：夏宝林杨娜殷晶晶汪仕韬张维益江阴市食品安全检测中心江苏江阴214400

采用同位素内标-超高效液相色谱-串联质谱技术,建立了一种能够快速、稳定地检测新鲜银耳中米酵菌酸与异米酵菌酸的分析方法。样品中加入自制的混合内标工作液后,用含3%乙酸的正己烷振荡提取,经Oasis MAX柱富集净化,利用waters Acquity U... 详细信息

采用同位素内标-超高效液相色谱-串联质谱技术,建立了一种能够快速、稳定地检测新鲜银耳中米酵菌酸与异米酵菌酸的分析方法。样品中加入自制的混合内标工作液后,用含3%乙酸的正己烷振荡提取,经Oasis MAX柱富集净化,利用waters Acquity UPLC BEH C_(18)柱(50 mm×2.1 mm,1.7μm)进行分离,以乙腈-含0.1%甲酸的水溶液为流动相进行梯度洗脱,采用电喷雾负离子多反应监测模式进行扫描,内标法定量。结果显示,米酵菌酸与异米酵菌酸在1~100 ng/mL范围内的线性关系良好,相关系数的平方(r^(2))均大于0.999,方法的检出限和定量限分别为0.25和0.5μg/kg。在0.5、5、50μg/kg 3个浓度加标水平下,平均加标回收率为94.2%~107.3%,相对标准偏差为2.2%~5.7%。该法准确、灵敏、快速,适用于新鲜银耳中米酵菌酸与异米酵菌酸的检测。

关键词：超高效液相色谱-串联质谱同位素内标米酵菌酸异米酵菌酸新鲜银耳

Effects of nanoparticles on devitrification and recrystallization of aqueous glycerol and PEG-600 solutions

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Science China(Technological Sciences) 2014年第2期57卷 264-269页

作者： LV FuKou LIU baolin LI weiJie SOng XiaoYan Institute of Biothermal Science and Technology University of Shanghai for Science and Technology

Nanoparticles in solution offer unique electrical, mechanical and thermal properties due to their physical presence and interac- tion with the state of dispersion. This work is aimed to study the effects of hydroxyapatite （HA） nanoparticles on the behavior of devitrification and recrystallization of glycerol （60% w/w） and PEG-600 （50% w/w） solutions during warming. HA nano- particles of different sizes （20, 40, 60 nm） and concentrations （0.1%, 0.5%, w/w） were incorporated into solutions, and were studied by calorimetric analysis coupled with cryomicroscopy. The presence of HA nanoparticles has little effect on the devit- rification end temperatures, but affects the devitrification onset temperatures of glycerol and PEG-600 solutions. The investi- gation with the cryomicroscope observed that the ice morphologies of glycerol and PEG-600 solutions are dendritic and spher- ic respectively. The ice fraction of glycerol solution containing 0.1% HA with the size of 60 nm decreased to 2/5 of that of the solution without nanoparticles at -45℃. The ice fractions of PEG-600 solutions increased signifcantly between -64℃ and -54℃, and the ice fraction of PEG-600 solution without nanoparticles increased by 92% within the temperature range. The findings have significant implications for biomaterial cryopreservation, cryosurgery, and food manufacturing. The complexity of ice crystal growth kinetics in nanoparticle-containing solutions awaits further study.

关键词： nanoparticles devitrification recrystallization ice morphology ice fraction

THEORETICAL INVESTIGATION ON STATE OF LOAD DISTRIBUTION AMOng CONTACT BEARIngS OF DOUBLE CIRCULAR ARC HELICAL GEARS

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Chinese Journal of Mechanical Engineering 2000年第2期13卷 108-113页

作者： wu baolin (Gear Research Institute, Taiyuan University of Technology) 太原理工大学山西太原

A dynamic analysis approcach to investigate the state of load distribution among contact bearings of double circular are belical gears is proposed and a computer program is developed for calculating the factor of iced distribution based on the theory of w-N gears. The changing situations of load distribution among contact bearings of the gears influenced by main issues are analyzed by a series of parametric studies.

关键词： Double circular are belical gears State of load distribution Factor of load distribution Dynamic analysis

一种6倍无源增益低OSR低功耗的二阶NS SAR ADC

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微电子学 2024年第2期54卷 177-182页

作者：黄子琪徐卫林韦保林韦雪明李海鸥桂林电子科技大学广西精密导航技术与应用重点实验室广西桂林541004 桂林电子科技大学广西高校微电子器件与集成电路重点实验室广西桂林541004

针对一阶噪声整形(NS)往往需要增加功耗而以较高的过采样比(OSR)来实现较高的有效位数(ENOB),提出了一种低OSR、低功耗的二阶无源NS SAR ADC。该无源NS模块较高的无源增益可以更好地抑制比较器的噪声;其残差电压是通过开关MOS阵列复用... 详细信息

针对一阶噪声整形(NS)往往需要增加功耗而以较高的过采样比(OSR)来实现较高的有效位数(ENOB),提出了一种低OSR、低功耗的二阶无源NS SAR ADC。该无源NS模块较高的无源增益可以更好地抑制比较器的噪声;其残差电压是通过开关MOS阵列复用积分电容实现采样,从而无需额外的残差采样电容,避免了残差采样电容清零和残差采样时kT/C噪声的产生,因此减小了总的kT/C噪声。180 nm CMOS工艺仿真结果表明,在不使用数字校准的情况下,所设计的10位二阶无源NS SAR ADC电路以100 kS/s的采样率和5的OSR,实现了13.5位ENOB,电路功耗仅为6.98μw。

关键词：逐次逼近模数转换器无源噪声整形低功耗低过采样比残差电压

Hybrid polymer biomaterials for bone tissue regeneration

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Frontiers of Medicine 2019年第2期13卷 189-201页

作者： Bo Lei baolin Guo Kunal J.Rambhia Peter X.Ma Frontier Institute of Science and Technology Xi’an Jiaotong UniversityXi’an 710054China Department of Biomedical Engineering University of MichiganAnn ArborMI 48109USA Department of Biologic and Materials Sciences University of MichiganAnn ArborMI 48109USA Macromolecular Science and Engineering Center University of MichiganAnn ArborMI 48109USA Department of Material Science and Engineering University of MichiganAnn ArborMI 48109USA

Native tissues possess unparalleled physiochemical and biological functions, which can be attributed to their hybrid polymer composition and intrinsic bioactivity. However, there are also various concerns or limitations over the use of natural materials derived from animals or cadavers, including the potential immunogenicity, pathogen transmission, batch to batch consistence and mismatch in properties for various applications. Therefore, there is an increasing interest in developing degradable hybrid polymer biomaterials with controlled properties for highly efficient biomedical applications. There have been efforts to mimic the extracellular protein structure such as nanofibrous and composite scaffolds, to functionalize scaffold surface for improved cellular interaction, to incorporate controlled biomolecule release capacity to impart biological signaling, and to vary physical properties of scaffolds to regulate cellular behavior. In this review, we highlight the design and synthesis of degradable hybrid polymer biomaterials and focus on recent developments in osteoconductive, elastomeric, photoluminescent and electroactive hybrid polymers. The review further exemplifies their applications for bone tissue regeneration.

关键词： hybrid polymer bone regeneration tissue engineering biomaterials