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Floating silver film： A flexible surface-enhanced Raman spectroscopy substrate for direct liquid phase detection at gas-liquid interfaces

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Nano Research 2016年第4期9卷 1148-1158页

作者： zongyuan wang Minyue Li Wei wang Min Fang Qidi Sun Changjun Liu Collaborative Innovation Center of Chemical Science and Engineering School of Chemical Engineering and Technology Tianjin University Tianjin 300072 China

In recent years, surface-enhanced Raman spectroscopy （SERS） has developed rapidly and is used for the detection of molecules and biomolecules in liquids. However, few studies have focused on SERS using a water surface as the substrate. A floating metal film on water is desirable for an enhanced SERS performance. In this work, silver nanopartides （Ag NPs） encased in poly（vinylpyrrolidone） films （Ag-PVP films） were synthesized on the surface of an aqueous solution by room temperature electron reduction. A floating silver film on a water surface was thereby achieved and is reported for the first time. The synthesized Ag-PVP film is an excellent flexible substrate for SERS and has other potential appli- cations. Using the floating silver film as a flexible SERS substrate, 10-11 M of 4-aminothiophenol, 10^-6 M of riboflavin, 10^-9 M of 4-mercaptobenzoic acid, 10^-7 M of 4-mercaptophenol, and 10^-7 M of 4-aminobenzoic acid are identified, demonstrating potential use for the floating substrate in the liquid-phase detection of molecules.

关键词： liquid phase detection surface-enhanced Raman gas/liquid silver film poly(vinylpyrrolidone) electron reduction

Manipulating micro-electric field and coordination-saturated site configuration boosted activity and safety of frustrated single-atom Cu/O Lewis pair for acetylene hydrochlorination

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Nano Research 2023年第7期16卷 9039-9049页

作者： Junchen Peng Dandan Dong zongyuan wang Hong Yang Dongyang Qiao Qinqin wang Wei Sun Minmin Liu Jiajun wang Mingyuan Zhu Bin Dai Fei He Chaofeng Huang School of Chemistry and Chemical Engineering/State Key Laboratory Incubation Base for Green Processing of Chemical Engineering Shihezi UniversityShihezi 832000China School of Chemistry and Chemical Engineering Southeast UniversityNanjing 211189China School of Materials Science and Engineering Key Laboratory of Advanced Ceramics and Machining Technology of Ministry of EducationTianjin UniversityTianjin 300072China College of Chemistry&Chemical Engineering Yantai UniversityYantai 264010China School of Material Science and Engineering University of JinanJinan 250022China

Simultaneously boosting acetylene hydrochlorination activity and avoiding formation of explosive copper acetylide over Cu-based catalyst,which represented a promising alternative to Hg-based and noble metal catalysts,remained ***,we fabricated a frustrated single-atom Cu/O Lewis pair catalyst(Cu/O-FLP)by coupling epoxide group(C-O-C)with atomdispersed Cu-cis-N_(2)C_(2)Cl center to address this *** basic epoxy site modulated the electron-deficient state of Lewisacidic Cu center and paired with the Cu-cis-N_(2)C_(2)Cl moiety to preferentially break HCl into different electronegative Cu-Clδ-and C-O-H^(δ+)intermediates,which further induced both an extra localized electric field to polarize acetylene and a upshift of the dband center of catalyst,thereby promoting adsorption and enrichment of acetylene by enhancing the dipolar interaction between acetylene and active ***,the generated Cu-Clδ-and C-O-H^(δ+)drastically reduced the energy barrier of ratelimiting step and made vinyl chloride easier to desorb from the Lewis-basic oxygen-atom site rather than traditional Lewis-acidic Cu *** superiorities ensured a higher activity of Cu/O-FLP compared with its ***,preferential dissociation of HCl endowed single-atom Cu with the coordination-saturated configuration,which impeded formation of explosive copper acetylide by avoiding the direct interaction between Cu and acetylene,ensuring the intrinsic safety during catalysis.

关键词： acetylene hydrochlorination Lewis pair single-atom Cu site configuration electric field

Effect of Sodium Tripolyphosphate and Silica Fume on Hydration of High Alumina Cement

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Journal of Wuhan University of Technology(Materials Science) 2024年第5期39卷 1246-1252页

作者： wang Jingran YANG zongyuan ZHANG Shuai ZHANG Jinhua HAN Bingqiang KE Changming The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081China

It was found that silica fume can reduce the maximum hydration heat release rate of cement by microcalorimetry,inhibit CAH_(10),promote the generation of C_(3)AH_(6)and strätlingite C_(2)ASH_(8),or promote the conversion of CAH_(10)to C_(3)AH_(6).Sodium tripolyphosphate can retard the early hydration of cement,have a slight effect on 1 d hydration products of cement and inhibit the generation hydration *** tripolyphosphate and silica fume can promote the early hydration of cement,advance the formation of C_(2)ASH_(8)or the conversion from CAH_(10)to C_(3)AH_(6)at 1 d.

关键词： high aluminum cement silica fume dispersing agent hydration

Nonstationary channel model of reentry plasma sheath for spacecraft: Overview, parameter estimation, and perspective

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Chinese Journal of Aeronautics 2024年第10期37卷 26-49页

作者： Lei SHI zongyuan LIU Weimin BAO Bo YAO Yifan wang Xiaoping LI Yanming LIU Fangyan LI School of Aerospace Science and Technology Xidian UniversityXi’an 710126China Key Laboratory of Equipment Efficiency in Extreme Environment Ministry of EducationXi’an 710126China China Aerospace Science and Technology Corporation Beijing 100048China

The Tracking,Telemetering,and Command(TT&C)communication of spacecraft faces severe limitations during *** Electromagnetic(EM)propagation channel is influenced by changes in the flight state and fluid *** addition to the high-speed spatial channel,the Plasma Sheath Channel(PSC),which covers the surface of spacecraft,exhibits unique nonstationary and highly dynamic time-varying *** absence of a channel model for the reentry process of spacecraft negatively impacts the quality evaluation and system design of TT&C *** paper summarizes the methods for nonstationary PSC modeling,involving calculation methods for attenuation and phase shift in the channel,as well as a multistate nonstationary channel statistical model based on a hidden Markov ***,the correlation between amplitude variation and phase variation with electron density is *** paper also provides statistical characteristics of the channel and channel parameters at typical frequencies in the S/C/X/Ka *** findings serve as a reference for the design and evaluation of TT&C communication systems for reentry ***,the paper discusses the prospects of various aspects related to the channel characteristics and modeling of spacecraft PSCs in the shortwave and terahertz/laser bands,as well as the potential challenges in cross-domain spacecraft channel sensing and prediction.

关键词： Spacecraft Plasma sheaths Electromagnetic wave transmission Communication channels Channel estimation

Applying Dairy Cow Behavior in Management Practice

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Journal of Northeast Agricultural University(English Edition) 2009年第1期16卷 86-92页

作者： YUAN Kai LIU Zongping wang zongyuan College of Veterinary Medicine Yangzhou University Yangzhou 225009 China

Applying dairy cow behavior in management practice is an effective way of improving cow health, welfare and performance. This paper first reviewed daily time budget and normal patterns of dairy cow behavior, and then discussed the influence of major management conditions and practices （such as competitive environments, stocking density, grouping strategies） on cow＇s feeding, lying and social behavior. Finally, new findings of using feeding behavior to predict disorders in transition period were addressed. It was suggested that dairy researchers and farmers should take advantage of related knowledge of dairy cow behavior to improve dairy cow health and welfare. More research is required to further study dairy cow behavior so as to better apply it in practical management and meet the needs of production.

关键词： dairy cows behavior management

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当归内生真菌分离及其次级代谢产物活性评价

中国中医药信息杂志 2024年第4期31卷 139-145页

作者：赵毓杰王楠黄明王宗元杜雅娟赵肖肖李洋裴佳梅陈垲林王蓓张新国兰州理工大学生命科学与工程学院甘肃省中藏药筛选评价及深加工重点实验室甘肃兰州730050 临洮县中医院甘肃定西730500 兰州市动物疫病预防控制中心甘肃兰州730050 甘肃省药品检验研究院甘肃兰州730070

目的分离当归内生真菌并对其次级代谢产物进行生物活性评价。方法以当归及其根际土壤为材料,选用6种培养基采用组织匀浆法分离内生菌,采用96孔板法测定次级代谢物的抑菌活性,紫外分光光度法评价4种酶抑制活性。结果从当归的根、茎、叶... 详细信息

目的分离当归内生真菌并对其次级代谢产物进行生物活性评价。方法以当归及其根际土壤为材料,选用6种培养基采用组织匀浆法分离内生菌,采用96孔板法测定次级代谢物的抑菌活性,紫外分光光度法评价4种酶抑制活性。结果从当归的根、茎、叶及土壤中共分离纯化得到153株真菌,对腺苷脱氨酶、β-内酰胺酶、黄嘌呤氧化酶和酪氨酸酶有一定抑制活性样品分别为45.83%、52.78%、51.39%、55.56%;对4种指示菌有广谱抑制作用样品为1.39%,菌株6B对大肠埃希菌ATCC25922、ATCC35218的最低抑菌浓度为62.5、7.81μg/mL。结论当归内生真菌资源丰富,是活性化合物发现的良好来源,具有一定研究价值。

关键词：当归根际土壤内生真菌分离鉴定酶抑制活性抑菌活性

BICs-enhanced active terahertz wavefront modulator enabled by laser-cut graphene ribbons

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光子学研究:英文版 2023年第7期11卷 1185-1195页

作者： JIANZHOU HUANG BIN HU GUOCUI wang zongyuan wang JINLONG LI JUAN LIU YAN ZHANG Beijing Engineering Research Center for Mixed Reality and Advanced Display School of Optics and PhotonicsBeijing Institute of TechnologyBeijing 100081China Beijing Key Laboratory for Metamaterials and Devices Key Laboratory of Terahertz OptoelectronicsMinistry of Educationand Beijing Advanced Innovation Center for Imaging TechnologyDepartment of PhysicsCapital Normal UniversityBeijing 100048China

Graphene-based terahertz(THz)metasurfaces combined with metallic antennas have the advantages of ultrasmall thickness,electrical tunability,and fast tuning ***,their tuning ability is limited by nonindependently tunable pixels and low modulation depth due to the ultra-small thickness of ***,we demonstrate a reconfigurable THz phase modulator with 5×5 independently tunable units enabled by switching the voltages applied on 10 graphene ribbons prepared by laser *** addition,by introducing quasibound states in the continuum resonance through a designed double C-shaped antenna,the efficiency of the device is enhanced by 2.7–3.6 times under different graphene chemical *** results demonstrate that a focus can be formed,and the focal length is changed from 14.3 mm to 22.6 *** work provides potential for compact THz spatial light modulators that may be applied in THz communication,detection,and imaging.

关键词： modulator tuning laser

学生t量测分布下鲁棒粒子滤波算法的设计与实现

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电子与信息学报 2019年第12期41卷 2957-2964页

作者：王宗原周卫东哈尔滨工程大学自动化学院哈尔滨150001 哈尔滨工程大学数学科学学院哈尔滨150001

野值是一种异于总体数据的非高斯量测值,在实际传输中野值的加入常使信号出现厚尾特性。粒子滤波是基于贝叶斯框架的适用于非线性/非高斯系统的一种滤波方法。如果在量测噪声中存在野值会使粒子滤波的精度下降。该文利用学生t分布建模... 详细信息

野值是一种异于总体数据的非高斯量测值,在实际传输中野值的加入常使信号出现厚尾特性。粒子滤波是基于贝叶斯框架的适用于非线性/非高斯系统的一种滤波方法。如果在量测噪声中存在野值会使粒子滤波的精度下降。该文利用学生t分布建模量测噪声模型,结合变分贝叶斯(VB)递推方法设计一种新颖的边缘粒子滤波(MPF-VBM),它在滤波同时可对量测噪声的包括均值在内的全部参数进行实时估计。进一步,利用该估计算法,在量测噪声时变条件下研究了噪声关联的粒子滤波算法(MPF-VBM-COR)。通过对典型单变量增长模型的仿真,验证了所提两种算法相比于已有算法在状态估计上具有更优越的鲁棒性。

关键词：粒子滤波变分贝叶斯均值估计噪声关联学生t分布

柔性空间机械臂系统的模糊滑模神经网络控制及柔性振动主动抑制

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空间科学学报 2013年第5期33卷 569-576页

作者：王宗源陈力福州大学机械工程及自动化学院福州350108 福建省制造业数字化设计工程研究中心福州350002

研究了参数不确定漂浮基柔性空间机械臂关节空间的轨迹跟踪及柔性振动主动控制问题.运用虚拟力概念,生成能同时反映柔性振动和刚性运动的虚拟期望轨迹,设计了一种自适应非奇异Terminal滑模控制器来跟踪该虚拟期望轨迹,以实现载体姿态及... 详细信息

研究了参数不确定漂浮基柔性空间机械臂关节空间的轨迹跟踪及柔性振动主动控制问题.运用虚拟力概念,生成能同时反映柔性振动和刚性运动的虚拟期望轨迹,设计了一种自适应非奇异Terminal滑模控制器来跟踪该虚拟期望轨迹,以实现载体姿态及关节稳定跟踪运动轨迹并对所产生的柔性振动进行主动抑制的控制目标.所设计的控制器结合了Terminal滑模控制快速收敛性,模糊小波神经网络优良的函数逼近特性及鲁棒技术处理逼近误差的优势,利用自适应算法在线自适应调节模糊小波神经网络的所有网络权值和参数,使控制器具有很强的鲁棒性.仿真实验证明了所提控制方案的有效性.

关键词：漂浮基柔性空间机械臂虚拟期望轨迹非奇异Terminal滑模控制模糊小波神经网络