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Particuology 2024年第6期89卷 246-257页

作者： Yanghong Wang Ziqiang Meng zipei zhang Min Xia Li Xia Wei Li School of Optical and Electronic Information Huazhong University of Science and TechnologyWuhan 430074China

Dynamic light scattering(DLS)is a nondestructive,well-established technique for the size characterization of proteins,nanoparticles,polymers,and colloidal ***,current DLS techniques are only applied to particle groups of single composition due to the limitation of their inversion *** this study,we propose a particle size distribution inversion algorithm based on the Tikhnonov regularization method that can be applied to the dual-substance particle *** algorithm retrieves the particle size distributions of two substances,respectively,by taking advantage of their refractive index *** simulation results reveal that the algorithm has excellent accuracy and stability when the scattering angle is 30°.Instead of the original identity matrix,the first-order difference matrix and second-order difference matrix are used as the regular matrix when utilizing the Tikhnonov algorithm,which obviously improves the anti-interference,accuracy,and stability of the ***,the inversion of particle size distribution is carried out at a 0.01%–1%noise level,which shows that the algorithm has an available antinoise ***,experimental particle size measurements for a mixture of polystyrene beads and toner particles demonstrate that the proposed algorithm is superior to the traditional Tikhnonov algorithm in applicability and accuracy.

关键词： Dynamic light scattering Dual-substance mixture Particle sized istribution Tikhnonov regularization

Decoupling of thermoelectric transport performance of Ag doped and Se alloyed tellurium induced by carrier mobility compensation

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Journal of Materials Science & Technology 2022年第6期101卷 71-79页

作者： Yue Wu Xiaofan zhang Boyi Wang Jingxuan Liang zipei zhang Jiawei Yang Ximeng Dong Shuqi Zheng Huai-zhou Zhao State Key Laboratory of Heavy Oil Processing College of New Energy and MaterialsChina University of PetroleumBeijing 102249China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing 100190China

Alloying with Se is proved to be feasible to suppress the lattice thermal conductivity(κL)of tellurium by introducing multidimensional lattice ***,extra ionization impurity centers induced by Se alloying are harmful to the electric transport properties of the *** this paper,we propose that the incorporation of Ag could successfully compensate the lost carrier mobility(μH)due to Se alloying through the regulation of microstructure,resulting in the higher power factor(PF)than that of samples without *** composition optimization,theκLdecreased from 1.29 W m^(-1)K^(-1) of Te_(0.99)Sb_(0.01) to 1.05 W m^(-1)K^(-1) of Te_(0.94)Ag_(0.02)Se_(0.03)Sb_(0.01) at 350 K,while the PF remained unchanged or even slightly *** from the synergistic effect of carrier mobility compensation and phonon scattering,a maximum z T of 0.91 at 573 K and an average z T of 0.57(between 298 and 573 K)are achieved in Te_(0.94)Ag_(0.02)Se_(0.03)Sb_(0.01).This work presents a new strategy for decoupling the thermal and electric parameters of Te-based thermoelectric materials.

关键词： Te Ag doping Microstructure regulation Mobility compensation

Defect engineering synergistically modulates power factor and thermal conductivity of CuGaTe2 for ultra-high thermoelectric performance

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Journal of Materials Science & Technology 2022年第33期128卷 213-220页

作者： zipei zhang Wenhao Li Lu Yu Sitong Wei Shikai Wei Zhen Ji Weiyu Song Shuqi Zheng State Key Laboratory of Heavy Oil Processing College of New Energy and MaterialsChina University of PetroleumBeijing 102249China College of Science China University of PetroleumBeijing 102249China

The ternary chalcopyrite CuGaTe_(2)has emerged as a promising p-type thermoelectric material with its advantages of low cost,good stability,and non-toxic ***,its thermoelectric performance is limited by the intrinsic low electrical conductivity and high lattice thermal *** this work,A deficiency of Cu in Cu_(1–x)Ga Te_(2)semiconductors can be used to optimize the electrical properties by improving the carrier concentration and to reduce thermal conductivity through multi-scale phonon scattering,which is predicted and guided by the First-principles density functional theory *** carrier concentration is increased to 1020,which compensates for the low electrical performance caused by the intrinsic low nHof CuGaTe_(2).The average power factor of Cu_(0.96)Ga Te_(2)reaches 106.3%higher than that of the original CuGaTe_(2).In addition,the lattice thermal conductivity of the defective samples is greatly reduced at high temperatures,which is mainly due to the reduction of sound speed and phonon *** the above factors contribute to the highest dimensionless figure of merit(ZT)value of 1.23 at 823 K in Cu_(0.96)GaTe_(2),which is 114%higher than the pristine CuGaTe_(2),and the average ZT is 171.4%higher.

关键词： Thermoelectric CuGaTe_(2) Carrier concentration Thermal conductivity

Enhanced thermoelectric performance in n-type Mg_(3.2)Sb_(1.5)Bi_(0.5) doping with lanthanides at the Mg site

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Journal of Materials Science & Technology 2022年第32期127卷 108-114页

作者： Lu Yu zipei zhang Juan Li Wenhao Li Shikai Wei Sitong Wei Guiwu Lu Weiyu Song Shuqi Zheng State Key Laboratory of Heavy Oil Processing College of New Energy and MaterialsChina University of PetroleumBeijing 102249China College of Science China University of PetroleumBeijing 102249China

Mg-based thermoelectric materials have attracted more and more attention because of their rich composition elements,green environmental protection,and lower *** recent years,the thermoelectric properties of n-type Mg_(3)Sb_(2) materials have been optimized by doping chalcogenide elements(S,Se,and Te)at the anionic *** this work,n-type Mg_(3.2)A_(x)Sb_(1.5)Bi_(0.5)(A=Gd,Ho;x=0.01,0.02,0.03,and 0.4)samples were prepared by the cation site doping of lanthanide elements(Gd and Ho).The research results show that Gd and Ho doped n-type Mg3.2Sb1.5Bi0.5samples are entirely comparable to the S,Se,and Te doped n-type Mg3.2Sb1.5Bi0.5samples,demonstrating more excellent thermoelectric *** with lanthanides(Gd and Ho)at the Mg site increases the carrier concentration of the material to 8.161×10^(19)cm^(-3).Doping induces the contribution of more electron,thus obtaining higher *** maximum zT value of the Mg_(3.2)Gd_(0.02)Sb_(1.5)Bi_(0.5) and the Mg_(3.2)Ho_(0.02)Sb_(1.5)Bi_(0.5) samples reaches 1.61 and 1.55,*** work theoretically and experimentally demonstrates Gd and Ho are efficient n-type dopants for Mg_(3.2)Sb_(1.5)Bi_(0.5) thermoelectric material.

关键词： Thermoelectric material First-principles calculation Mg_(3.2)Sb_(1.5)Bi_(0.5)

Achieving high thermoelectric performance through carrier concentration optimization and energy filtering in Cu_(3)SbSe_(4)-based materials

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Journal of Materiomics 2022年第5期8卷 929-936页

作者： Sitong Wei Boyi Wang zipei zhang Wenhao Li Lu Yu Shikai Wei Zhen Ji Weiyu Song Shuqi Zheng College of New Energy and Materials China University of PetroleumBeijing102249China Beijing National Laboratory for Condensed Matter Physics Institute of PhysicsChinese Academy of SciencesBeijing100190China School of Physical Sciences University of Chinese Academy of SciencesBeijing100049China College of Science China University of PetroleumBeijing102249China

The previous works commonly adjust the carrier concentration through acceptor doping,but at the same time,the decrease of the Seebeck coefficient limits the further improvement of electrical properties in Cu_(3)SbSe_(4)-based *** this work,a microwave-assisted hydrothermal synthesis method was used to synthesize Cu_(3)SbSe_(4)/TiO_(2) hollow *** of TiO_(2) participates in the reaction,replaces the Sb site of Cu_(3)SbSe_(4) to form holes,and the rest is dispersed in the matrix in the form of the second *** first-principles calculations reveal that the doping of Ti significantly changes the band structure and phonon spectrum,thereby regulating carrier concentration while increasing phonon *** addition,experimental results show that the energy filtering effect generated by the extra-mixed TiO_(2) nano particles,which suppresses the decrease of Seebeck coefficient by acceptor ***,the highest average power factor 897.5 mW m^(-1) K^(-2) and the zT peak value of 0.70 can be obtained in Cu_(3)SbSe_(4)/6%TiO_(2) sample at 298e623 *** work provides a new sight to improve the thermoelectric properties in Cu_(3)SbSe_(4) through carrier concentration regulation and nano-phase composition.

关键词： Cu_(3)SbSe_(4)/Nano-TiO_(2) Energy filtering effect Thermoelectric Synergistic modulation

A nitric oxide-triggered hydrolysis reaction to construct controlled self-assemblies with complex topologies

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Science China Chemistry 2024年第4期67卷 1289-1299页

作者： Wenzhuo Chen Yuping Tang Shuai Chen zipei Chen Jia He Hongbin Huo Juan zhang Jiajia Li Fei Yan Wei Tian Laboratory of Shaanxi Administration of Traditional Chinese Medicine for TCM Compatibility Shaanxi Key Laboratory of Chinese Medicine Fundamentals and New Drugs ResearchCollege of PharmacyShaanxi University of Chinese MedicineXianyang 712046China Shaanxi Key Laboratory of Macromolecular Science and Technology Xi’an Key Laboratory of Hybrid Luminescent Materials and Photonic DeviceMOE Key Laboratory of Material Physics and Chemistry under Extraordinary ConditionsSchool of Chemistry and Chemical EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Department of Polymeric Materials School of Materials Science and EngineeringTongji UniversityShanghai 201804China

Hydrolysis reactions are capable of directing the non-equilibrium assembly of biomolecular scaffolds to realize sophisticated structures and functions in natural ***,utilizing the proper hydrolysis reactions to construct controlled assemblies with complex topologies is still an arduous challenge in artificial systems and needs to be ***,we report a nitric oxide(NO)-triggered slow hydrolysis strategy for the controlled construction of biomimetic supramolecular toroids(STs),thus realizing their visualization of intermediate structures and regulation of geometry *** presented protocol harnesses hydrolysis reactions to control of non-equilibrium self-assembly processes for the construction of self-assemblies with complex topologies successfully,which sheds light on how the hydrolysis reaction rate can modulate the kinetic pathway of assembly,thus realizing the artificial establishment of bio-inspired hierarchical structures.

关键词： supramolecular toroids controlled self-assembly nitic oxide-triggered hydrolysis pathway regulation

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Synergistic band convergence and defect engineering boost thermoelectric performance of SnTe

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Journal of Materials Science & Technology 2021年第27期86卷 204-209页

作者： Ximeng Dong Wenlin Cui Wei-Di Liu Shuqi Zheng Lei Gao Luo Yue Yue Wu Boyi Wang zipei zhang Liqiang Chen Zhi-Gang Chen State Key Laboratory of Heavy Oil Processing College of New Energy and MaterialsChina University of PetroleumBeijing 120049PR China State Key Laboratory of Heavy Oil Processing College of ScienceChina University of PetroleumBeijing 102249PR China Centre for Future Materials University of Southern QueenslandSpringfield CentralQueensland 4300Australia School of Mechanical and Mining Engineering The University of QueenslandBrisbaneQueensland 4072Australia State Key Laboratory of Advanced Power Transmission Technology Global Energy Interconnection Research Institute Co.Ltd.Changping DistrictBeijing 102211PR China Beijing Key Laboratory of Failure Corrosion and Protection of Oil/gas Facilities and Department of Materials Science and EngineeringCollege of New Energy and MaterialsChina University of PetroleumBeijing 102249PR China

As an eco-friendly thermoelectric material,Sn Te has attracted extensive *** this study,we use a stepwise strategy to enhance the thermoelectric performance of Sn ***,Ag Cl is doped into Sn Te to realize band convergence and enlarge the band gap of Ag Cl-doped Sn *** Cl-doping also induces dense point defects,strengthens the phonon scattering,and reduces the lattice thermal ***,Sb is alloyed into Ag Cl-doped Sn Te to further optimize the carrier concentration and simultaneously reduce the lattice thermal conductivity,leading to improved thermoelectric dimensionless figure of merit,***,(Sn_(0.81)Sb_(0.19)Te)_(0.93)(Ag Cl)_(0.07)has approached the ZT value as high as~0.87 at 773 K,which is 272%higher than that of pristine Sn *** study indicates that stepwise Ag Cl-doping and Sb-alloying can significantly improve thermoelectric performance of Sn Te due to synergistic band engineering,carrier concentration optimization and defect engineering.

关键词： Thermoelectric SnTe Stepwise optimize Band structure Lattice thermal conductivity

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风雷软件LES开发设计与验证

航空学报 2023年第6期44卷 151-168页

作者：张子佩赵钟陈坚强刘健邓小兵空气动力学国家重点实验室绵阳621000 中国空气动力研究与发展中心计算空气动力研究所绵阳621000

基于国家数值风洞风雷软件开源框架,设计开发了LES(Large Eddy Simulation)湍流模型,主要包括Fourier谱/有限差分方法 LES求解器和有限体积/有限差分方法 LES求解器。简要介绍了采用的不可压缩流动求解的投影法、Fourier谱/有限差分混... 详细信息

基于国家数值风洞风雷软件开源框架,设计开发了LES(Large Eddy Simulation)湍流模型,主要包括Fourier谱/有限差分方法 LES求解器和有限体积/有限差分方法 LES求解器。简要介绍了采用的不可压缩流动求解的投影法、Fourier谱/有限差分混合方法、亚格子模型等理论方法,给出设计的软件框架和计算流程,尤其说明采用的松/紧2种耦合模式。通过数值模拟不可压缩槽道湍流、亚临界雷诺数圆柱绕流、NACA0012临界攻角的低频振荡算例,验证求解器的计算精度和复杂湍流模拟能力。基于风雷开源框架设计的开源LES模型,具备高精度数值格式、亚格子模型、湍流统计等通用模块,可为国内学者提供一个LES湍流模拟研究的开放平台。

关键词：大涡模拟国家数值风洞(NNW)工程风雷软件投影法 Fourier谱/有限差分方法不可压缩槽道流动圆柱绕流低频振荡

适用于宽速域湍流流动的新型混合对称超松弛隐式时间格式评估

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Acta Mechanica Sinica 2023年第6期39卷 46-55页

作者：刘健陈坚强张子佩杨玉峰肖志祥 State Key Laboratory of Aerodynamics Mianyang 621000China China Aerodynamics Research and Development Center Mianyang 621000China School of Aerospace Engineering Tsinghua UniversityBeijing 100084China

N-S方程的时间离散格式的收敛效率和数值稳定性对工程湍流计算的意义十分重要.通过对原始标量型和矩阵型对称超松弛隐式时间格式的分析,提出了一种基于当地马赫数的混合型对称超松弛隐式时间格式.该格式兼顾了标量型和矩阵型对称超松弛... 详细信息

N-S方程的时间离散格式的收敛效率和数值稳定性对工程湍流计算的意义十分重要.通过对原始标量型和矩阵型对称超松弛隐式时间格式的分析,提出了一种基于当地马赫数的混合型对称超松弛隐式时间格式.该格式兼顾了标量型和矩阵型对称超松弛格式的优点,被应用于从低速到高超声速的多个湍流流动的计算.通过计算结果的对比表明,新的混合型对称超松弛格式在较宽速域的湍流流动模拟中,由于其高的计算效率和优异的数值稳定性,表现出了最好的收敛特性.该新型混合对称超松弛格式将有望广泛应用于工程湍流流动的计算.

关键词：湍流流动数值稳定性矩阵型收敛效率收敛特性湍流计算计算效率混合型

结合状态机和动态目标路径的无人驾驶决策仿真

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中国图象图形学报 2019年第2期24卷 313-323页

作者：范鑫淼何武张梓培四川师范大学影视与传媒学院成都610068 四川师范大学可视化计算与虚拟现实四川重点实验室成都610068

目的决策系统是无人驾驶技术的核心研究之一。已有决策系统存在逻辑不合理、计算效率低、应用场景局限等问题,因此提出一种动态环境下无人驾驶路径决策仿真。方法首先,基于规则模型构建适于无人驾驶决策系统的交通有限状态机;其次,针对... 详细信息

目的决策系统是无人驾驶技术的核心研究之一。已有决策系统存在逻辑不合理、计算效率低、应用场景局限等问题,因此提出一种动态环境下无人驾驶路径决策仿真。方法首先,基于规则模型构建适于无人驾驶决策系统的交通有限状态机;其次,针对交通动态特征,提出基于统计模型的动态目标路径算法计算状态迁移风险;最后,将交通状态机和动态目标路径算法有机结合,设计出一种基于有限状态机的无人驾驶动态目标路径模型,适用于交叉口冲突避免和三车道换道行为。将全速度差连续跟驰模型运用到换道规则中,并基于冲突时间提出动态临界跟车距离。结果为验证模型的有效性和高效性,对交通环境进行虚拟现实建模,模拟交叉口通行和三车道换道行为,分析文中模型对车流量和换道率的影响。实验结果显示,在交叉口通行时,自主车辆不仅可以检测冲突还可以根据风险评估结果执行安全合理的决策。三车道换道时,自主车辆既可以实现紧急让道,也可以通过执行换道达成自身驾驶期望。通过将实测数据和其他两种方法对比,当车流密度在0. 2 0. 5时,本文模型的平均速度最高分别提高32 km/h和22 km/h。当车流密度不超过0. 65时,本文模型的换道成功率最高分别提升37%和25%。结论实验结果说明本文方法不仅可以在动态城区环境下提高决策安全性和正确性,还可以提高车流量饱和度,缓解交通堵塞。

关键词：风险系数换道行为冲突避免无人驾驶技术全速度差连续跟驰模型