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Synthesis and Characterization of Microcapsules with Chlorpyrifos Cores and Polyurea Walls

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Chemical Research in Chinese Universities 2006年第3期22卷 379-382页

作者： zhang Qiang zhang Pei-pei JIAO Qing-ze College of Science Beijing Institute of Technology Beijing 100081 P. R. China College of Chemistry and Environmental Science Beijing Institute of Technology Beijing 100081 P. R. China

Microcapsules with chlorpyrifos cores and polyurea walls were synthesized with 2,4-tolylene diisocyanate as an oil-soluble monomer and ethylenediamine as a water-soluble monomer via an interracial polycondensation reaction. The products were characterized by means of Fourier transform infrared spectrometry, ^13C NMR spectrometry and ^31p NMR spectrometry. The morphology, the particle size and the particle size distribution, and the thermal properties were also evaluated. The prepared microcapsules exhibit clear and smooth surfaces and have a mean diameter of 28. 13 μm. These microcapsules also have a good thermal stability for long-term use, and have potential applications in minimizing the toxicity of chlorpyrifos through controlled release.

关键词： Microcapsule Chlorpyrifos Polyurea Synthesis Characterization

Effects of sputtering power and annealing temperature on surface roughness of gold films for high-reflectivity synchrotron radiation mirrors

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Nuclear Science and Techniques 2019年第7期30卷 36-41页

作者： Jia-Qi Chen Qiu-Shi Huang run-ze Qi Yu-Fei Feng Jiang-Tao Feng Zhong zhang Wen-Bin Li Zhan-Shan Wang MOE Key Laboratory of Advanced Micro-Structured Materials Institute of Precision Optical Engineering (IPOE)School of Physics Science and Engineering Tongji University

Gold films deposited by direct current magnetron sputtering are used for synchrotron radiation optics. In this study, the microstructure and surface roughness of gold films were investigated for the purpose of developing high-reflectivity mirrors. The deposition process was first optimized. Films were fabricated at different sputtering powers (15, 40, 80, and 120 W) and characterized using grazing incidence X-ray reflectometry, X-ray diffraction, and atomic force microscopy. The results showed that all the films were highly textured, having a dominant Au (111) orientation, and the film deposited at 80 W had the lowest surface roughness. Subsequently, post-deposition annealing from 100 to 200℃ in a vacuum was performed on the films deposited at 80 W to investigate the effect of annealing on the microstructure and surface roughness of the films. The grain size, surface roughness, and their relationship were investigated as a function of annealing temperature. AFM and XRD results revealed that at annealing temperatures of 175 ℃ and below, microstructural change of the films was mainly manifested by the elimination of voids. At annealing temperatures higher than 175℃, grain coalescence occurred in addition to the void elimination, causing the surface roughness to increase.

关键词： Gold films Sputtering power Annealing Microstructure Roughness

Model predictive control with fractional-order delay compensation for fast sampling systems

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Science China(Information Sciences) 2021年第7期64卷 165-180页

作者： ze ZHOU Zhitao LIU Hongye SU Liyan zhang State Key Laboratory of Industrial Control Technology Institute of Cyber-Systems and ControlZhejiang University School of Automation Wuhan University of Technology

Model predictive control(MPC) is widely used in fast sampling systems owing to its fast regulating ability. However, the sampling delay is a key issue and tends to be a fractional multiple of the sampling period. If the fractional-order delay is not accurately offset, the controller output will exhibit errors, thus resulting in oscillations in controlled system. Moreover, the MPC delay compensation algorithm is limited to the computation time. To address the problems of fractional delay and computational burden in fast sampling systems, we propose a new method to compensate for the fractional-order sampling ***, we use a finite-impulse-response fractional delay filter based on a Lagrange interpolation polynomial to approximate the fractional portion. Moreover, we prove that high accuracy and simplicity can be ensured when the polynomial order is one. Then, we estimate the current state variable using the delayed sampling signal and control signals of past moments. Further, we obtain the current control signal according to the estimated state variable. By considering the simultaneous existence of computational and sampling delays,a full compensation strategy is proposed. Computational simulation results validate the proposed MPC algorithm with fractional-order delay compensation and demonstrate its advantages.

关键词： model predictive control fast sampling systems sampling delay fractional-order Lagrange interpolation polynomial

A review of composition evolution in Ni-based single crystal superalloys

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Journal of Materials Science & Technology 2020年第9期44卷 76-95页

作者： Wanshun Xia Xinbao Zhao Liang Yue ze zhang Institute of Superalloys Science and Technology School of Materials Science and EngineeringZhejiang UniversityHangzhou310027China Center of Electron Miscroscopy Zhejiang UniversityHangzhou310027China

Due to the outstanding creep performance, nickel-based single crystal superalloys(Ni-SXs) are extensively applied in modern aero-engine and industrial gas turbine. Apart from the special single crystal structure which is disadvantageous to extension of creep cracks, Ni-SXs derive the creep strength from intrinsic two-phase microstructure(γ phase and γ’ phase). Main microstructural parameters including volume fraction of γ’ phase and the lattice misfit, and the formation and distribution of precipitated phase are determined by the compositions of alloys. Besides, the creep properties are greatly influenced by these microstructural parameters and precipitated phase. This review has summarized the relationships between different alloying elements and microstructures and indicated their influence on creep properties of Ni-SXs. In addition, with the improvements of experimental methods and characterization technique, some recent discoveries have provided additional evidence to support or challenge the pervious creep theories of superalloys. In view of these new discoveries, this review has provided some perspectives which can be referenced in future compositional design of Ni-SXs.

关键词： Nickel-based single crystal superalloys Composition Creep properties Refractory elements

Study of Two-Mode Squeezed Magnetopolarons

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Communications in Theoretical Physics 2007年第4期47卷 747-751页

作者： zhang Yan-Min CHENG ze Department of Physics Huazhong University of Science and Technology Wuhan 430074 China

In this paper, we conduct an investigation into two-dimensional squeezed magnetopolarons. The Hamiltonian of magnetopolarons is dealt with two-mode squeezed states transformation, which is based on the Lee-Low-Pines and Huybrechts （LLP-H） canonical transformations. This method makes it possible to take account of the linear terms, bilinear ones of phonon operators, and the correlation between two longitudinal optical （LO） phonon modes. The energies of the ground state and excited states are evaluated by variational approach, and accurate results are obtained. Furthermore, the renormalized cyclotron masses for some possible transitions are discussed in detail.

关键词： magnetopolarons squeezed state electron-phonon interaction renormalized mass

Aerodynamic Performance Improvement of a Highly Loaded Compressor Airfoil with Coanda Jet Flap

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Journal of Thermal Science 2022年第1期31卷 151-162页

作者： zhang Jian DU Juan zhang Min CHEN ze zhang Hongwu NIE Chaoqun North China Electric Power University Beijing 100096China Advanced Gas Turbine Laboratory Institute of Engineering ThermophysicsChinese Academy of SciencesBeijing 100190China Key Laboratory of Advanced Energy and Power Chinese Academy of SciencesBeijing 100190China Innovation Academy for Light-Duty Gas Turbine Chinese Academy of SciencesBeijing 100190China School of Engineering Science University of Chinese Academy of SciencesBeijing 100190China Changsha University of Science&Technology Changsha 410114China

Coanda jet flap is an effective flow control technique,which offers pressurized high streamwise velocity to eliminate the boundary layer flow separation and increase the aerodynamic loading of compressor ***,there is only single-jet flap on the blade suction side.A novel Coanda double-jet flap configuration combining the front-jet slot near the blade leading edge and the rear-jet slot near the blade trailing edge is proposed and investigated in this *** reference highly loaded compressor profile is the Zierke&Deutsch double-circular-arc airfoil with the diffusion factor of ***,three types of Coanda jet flap configurations including front-jet,rear-jet and the novel double-jet flaps are designed based on the 2D flow fields in the highly loaded compressor blade *** Back Propagation Neural Network(BPNN)combined with the genetic algorithm(GA)is adopted to obtain the optimal geometry for each type of Coanda jet flap *** simulations are then performed to understand the effects of the three optimal Coanda jet flaps on the compressor airfoil *** indicate all the three types of Coanda jet flaps effectively improve the aerodynamic performance of the highly loaded airfoil,and the Coanda double-jet flap behaves best in controlling the boundary layer flow *** the inlet flow condition with incidence angle of 5°,the total pressure loss coefficient is reduced by 52.5%and the static pressure rise coefficient is increased by 25.7%with Coanda double-jet flap when the normalized jet mass flow ratio of the front jet and the rear jet is equal to 1.5%and 0.5%,*** impacts of geometric parameters and jet mass flow ratios on the airfoil aerodynamic performance are further *** is observed that the geometric design parameters of Coanda double-jet flap determine airfoil thickness and jet slot position,which plays the key role in supressing flow separation on the airfoil suction ***

关键词： Coanda jet flap high loaded compressor active flow control aerodynamic performance

Tumor Necrosis Factor a Reduces SNAP29 Dependent Autolysosome Formation to Increase Prion Protein Level and Promote Tumor Cell Migration

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Virologica Sinica 2021年第3期36卷 458-475页

作者： Huan Li Ren Wang ze Yu run Shi Jie zhang Shanshan Gao Ming Shao Shuzhong Cui Zhenxing Gao Jiang Xu Man-Sun Sy Chaoyang Li Wuhan Institute of Virology Chinese Academy of SciencesWuhan 430071China University of Chinese Academy of Sciences Beijing 100000China Affiliated Cancer Hospital and Institute of Guangzhou Medical University State Key Laboratory of Respiratory DiseaseGuangzhou 510095China Department of Stomatology First Affiliated HospitalSchool of MedicineShihezi UniversityShihezi 832008China Abdominal Surgery Affiliated Cancer Hospital and Institute of Guangzhou Medical UniversityGuangzhou 510095China Department of Pathology School of MedicineCase Western Reserve UniversityClevelandOH 44106USA

Tumor Necrosis Factor α(TNFα) is best known as a mediator of inflammation and immunity, and also plays important roles in tumor biology. However, the role of TNFα in tumor biology is complex and not completely understood. In a human melanoma cell line, M2, and a lung carcinoma cell line, A549, TNFα up-regulates prion protein(PrP) level, and promotes tumor cell migration in a PrP dependent manner. Silencing PRNP abrogates TNFα induced tumor cell migration;this phenotype is reversed when PRNP is re-introduced. Treatment with TNFα activates nuclear factor kappa B(NF-κB)signaling, which then mitigates autophagy by reducing the expression of Forkhead Box P3(FOXP3). Down regulation of FOXP3 reduces the transcription of synaptosome associated protein 29(SNAP29), which is essential in the fusion of autophagosome and lysosome creating autolysosome. FOXP3 being a bona fide transcription factor for SNAP29 is confirmed in a promoter binding assay. Accordingly, silencing SNAP29 in these cell lines also up-regulates PrP, and promotes tumor cell migration without TNFα treatment. But, when SNAP29 or FOXP3 is silenced in these cells, they are no longer respond to TNFα. Thus, a reduction in autophagy is the underlying mechanism by which expression of PrP is up-regulated,and tumor cell migration is enhanced upon TNFα treatment. Disrupting the TNFα-NF-κB-FOXP3-SNAP29 signaling axis may provide a therapeutic approach to mitigate tumor cell migration.

关键词： Tumor necrosis factorα(TNFα) Prion protein Synaptosome associated protein 29(SNAP29) Autophagy Nuclear factor kappa B(NF-κB) Forkhead box P3(FOXP3)

Temperature Dependence of Atomic Decay Rate

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Chinese Physics Letters 2012年第2期29卷 75-78页

作者： zhang Jian-Jun CHENG ze Department of Physics Huazhong University of Science and TechnologyWuhan 430074

We investigate the decay rate of an atom in a two-dimensional optical microcavity in which there exists a BoseEinstein condensation of *** is found that below the critical temperature To,the atomic decay rate depends on the absolute temperature ***,at absolute zero temperature almost all photons are in the condensate state,and the atom can be approximately treated as if it is in vacuum.

关键词： absolute decay approximate

Roles of Serum Amyloid A 1 Protein Isoforms in Rheumatoid Arthritis

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Engineering 2022年第3期8卷 174-182页

作者： Elaine Laihan Leung Huan-Ling Lai run-ze Li Hu-Dan Pan ze-Bo Jiang Ying Li Fu-Gang Duan Jia-Hui Xu Yi-Zhong zhang A-Xi Shi Chun-Li Wei Fang-Yuan zhang Xiao-Jun Yao Liang Liu State Key Laboratory of Quality Research in Chinese Medicine&Macao Institute for Applied Research in Medicine and Health&Faculty of Chinese Medicine Macao University of Science and TechnologyMacao 999078China Department of Pediatrics Pennsylvania State University College of MedicineHersheyPA 17033USA

Secondary amyloid A amyloidosis,a lethal complication,is induced when acute or chronic infection coexists with over-secretion of the serum amyloid A 1(SAA1)protein and deposition in key internal ***,using the whole-exome sequencing method,we identified a novel deleterious mutation SAA1.2 in rheumatoid arthritis(RA)***,the role of SAA1 in RA pathogenesis and its complications remains *** purpose of this study was to determine the pathogenetic roles of SAA1 protein isoforms in RA *** modified an experimental adenovirus infection protocol to introduce SAA1.2 gene alleles into the knee joints of mice and used SAA1.3 and SAA1.5 as *** tomography analysis was applied to determine changes in bone morphology and ***(IHC)analysis,flow cytometry,enzyme-linked immunosorbent assay(ELISA),and real-time polymerase chain reaction(RT-PCR)were used to investigate disease progression and cytokine alterations in the course of adenoviral SAA-induced knee joint inflammation and bone *** found that the arthritis-inducing effect of SAA1.2 transcription in the knee joints and mutant SAA1 protein secretion in blood resulted in the stimulation of immune responses,leading to CD8^(+)T cell and pro-inflammatory cytokine elevation,such as interleukin(IL)-6,IL-22,matrix metalloproteinase(MMP)-3,MMP-9,with subsequent synovial inflammation and bone *** findings indicate that SAA1 protein isoforms,particularly SAA1.2,play a significant role in the induction and progression of RA and may have potential value in the early diagnosis and severity prediction of RA.

关键词： Serum amyloid A 1 Rheumatoid arthritis Pathogenetic Intra-articular