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Chinese Journal of Integrative Medicine 2017年第8期23卷 570-573页

作者： HE Xu-feng PAN Wei-dong YAO Yi-li ZHANG Hui-min department of dermatol-ogy Shuguang HospitalShanghai University of Traditional Chinese Medicine Shanghai 201203 China

The histamine receptor antagonists in the treatment of allergic disease have *** treatments of Chinese herbs have some curative effects on allergic skin *** research indicates that the mitogen-activated protein kinase（MAPK）signaling pathway might be equally important in allergic *** was found that the inhibition of MAPK signaling pathways might relieve allergy symptoms,and some herbs can inhibit the MAPK pathway,which yields anti-allergy *** medicines（CMs）have immense potential in the development of treatments for allergic disease.

关键词： Chinese medicines allergic disease mitogen-activated protein kinase signalpathway

Inhibition of NO emission by adding antioxidant mixture in Jatropha biodiesel on the performance and emission characteristics of a C.I. engine

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Frontiers in Energy 2015年第2期9卷 238-245页

作者： A. PRABU R. B. ANAND department of Mechanical Engineering National Institute of Technol-ogy Tiruchirappalli 620015 India

In this paper, the effect of adding an antiox- idant mixture in Jatropha biodiesel as fuel, in a single cylinder, direct injection compression ignition engine was experimentally investigated and the level of pollutants in the exhaust and performance characteristics of the engine were analyzed. Nine test fuels were prepared with three antioxidants, namely, Suecinimide （C4H5NO2）, N,N-dimethyl-p-phenylenediamine-dihydrochloride （C8H14C12N2）, and N-phenyl-p-phenylenediamine （C6H5NHC6H4NH2） added to neat biodiesel at 500 parts per million （ppm）, 1000ppm and 2000ppm and the observed experimental results were compared with those of neat biodiese! and neat diesel as base fuels. The comparison showed that NO emission was reduced drastically for the test fuels with the antioxidant addition of 2000ppm. The maximum reduction of 10% of NO emission was observed for the antioxidant mixture in neat biodiesel, with a slight increase in unburned HC, CO and smoke opacity. In addition, the obtained experimental results reveal that the addition of two antioxidants as mixture in neat biodiesel caused improved NO emission reduction for all test fuels.

关键词： NO emission antioxidants Succinimide,N,N-dimethyl-p-phenylenediamine-dihydrochloride N-phenyl-p-phenylenediamine

Identifiability and sloppiness of structured systems with a matrix fraction description using finite frequency responses

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Science China(Information Sciences) 2025年第2期68卷 200-215页

作者： Yunxiang MA Tong ZHOU department of Automation Tsinghua University department of Automation and BNRist Tsinghua University

This paper investigates the identifiability of structured systems with a matrix fraction description and attacks practical difficulties in estimating parameters under finite frequency responses. The numerator and denominator polynomial matrices depend affinely on system parameters, which can represent a broad range of systems, especially circuits and mechanical systems. Except for assuming that the denominator matrix is invertible, no further assumptions are adopted. A criterion is provided for validating this assumption utilizing graph theories and matroids. A sufficient and necessary criterion for global identifiability based on the rank of a numerical matrix is given and can be recursively verified with each frequency point,which is computationally attractive for large-scale systems. For an identifiable system, an ellipsoid approximation is obtained for the set of parameters whose corresponding system frequency responses deviate within a specific range from those of the system at a specific parameter value. Using this approximation, explicit expressions for absolute and relative sloppiness have been derived, which can be used to quantify the difficulty of identifying system parameters. Comparisons with the well-known Fisher information matrix have also been performed through a mechanical system, revealing significant differences in quantifying parameter estimation hardness.

关键词： identifiability sloppiness structured system matrix fraction graph theory matroid

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Transport mechanism in chemically reactive hybrid nanofluid flow containing gyrotactic micro-organisms over a curved oscillatory surface

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 177-192页

作者： M.NAVEED M.IMRAN T.ASGHAR Z.ABBAS department of Mathematics Division of Science and TechnologyUniversity of Education department of Mathematics The Islamia University of Bahawalpur

This paper examines the transport analysis, including both heat transfer and mass transfer, in hybrid nanofluid flow containing gyrotactic microorganisms towards a curved oscillatory surface. The influence of magnetic fields is also inspected in terms of their physical characteristics. To depict the phenomena of transport, modified versions of both Fick's and Fourier's laws are used. Additionally, the characteristics of both heterogeneous and homogeneous chemical reactions are also incorporated. Utilizing a curvilinear coordinate system, the flow problem is formulated as partial differential equations(PDEs)for momentum, concentration, microorganism field, and energy. An analytical solution to the obtained flow equations is achieved utilizing the homotopy analysis method(HAM).The effects of significant flow parameters on the pressure and microorganism fields, velocity, oscillation velocity, concentration, and temperature distributions are shown via graphs. Furthermore, the variations in skin friction, mass transfer rate, heat transfer rate, and local motile number due to different involved parameters are presented in tables and are analyzed in detail. Graphical results indicate that the curves of velocity and temperature fields are enhanced as the values of the solid volume fraction variables *** is also verified that the concentration rate field decreases as the values of the homogeneous reaction strength parameter and the radius of curvature parameter increase, and it increases with the Schmidt number and the heterogeneous reaction strength *** outcomes show a favorable response of the motile number to advanced values of the Peclet number, the Schmidt number, the microorganism difference parameter, and the bio-convective Lewis number.

关键词： analytical solution Cattaneo-Christov heat and mass flux chemical reaction gyrotactic microorganism hybrid nanofluid O368 oscillating curved stretchable sheet

Assessing the effects of different dielectrics onenvironmentally conscious powder-mixed EDM of difficult-to-machine material （WC-Co）

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Frontiers of Mechanical Engineering 2016年第4期11卷 374-387页

作者： Jagdeep SINGH Rajiv Kumar SHARMA department of Mechanical Engineering National Institute of Technol-ogy Hamirpur Himachal Pradesh-177005 India

Electrical discharge machining (EDM) is a well-known nontraditional manufacturing process to machine the difficult-to-machine (DTM) materials which have unique hardness properties. Researchers have successfully performed hybridization to improve this process by incorporating powders into the EDM process known as powder-mixed EDM process. This process drastically improves process efficiency by increasing material removal rate, micro-hardness, as well as reducing the tool wear rate and surface roughness. EDM also has some input parameters, including pulse-on time, dielectric levels and its type, current setting, flushing pressure, and so on, which have a significant effect on EDM performance. However, despite their positive influence, investigating the effects of these parameters on environmental conditions is necessary. Most studies demonstrate the use of kerosene oil as dielectric fluid. Nevertheless, in this work, the authors highlight the findings with respect to three different dielectric fluids, including kerosene oil, EDM oil, and distilled water using one-variable-at-a-time approach for machining as well as environmental aspects. The hazard and operability analysis is employed to identify the inherent safety factors associated with powder-mixed EDM of WC-Co.

关键词： WC hazard and operability analysis (HAZOP) discharging aerosol concentration dielectrics powders

The dynamic effects of solar eclipses of October 25,2022,and October 14,2023,on GPS-derived total electron content

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Geodesy and Geodynamics 2025年第1期16卷 75-86页

作者： Vishal Chauhan Vishakha Rakesh Singh Shishupal Singh Vikram Singh Om Prakash Singh department of Physics Graphic Era Hill University department of Petroleum Engineering Graphic Era (Deemed to be University) department of Physics St.John's College department of Applied Sciences & Humanities Institute of Engineering & Technology

This study analyzes total electron content(TEC) variations during two solar eclipse events that occurred on October 25, 2022, and October 14, 2023. The solar eclipse of October 25, 2022, was a partial solar eclipse, while the eclipse of October 14, 2023, was an annular solar eclipse. For this study, the data of eight International GNSS Service(IGS) stations from different eclipse coverage zones are used to analyze TEC variations. It is found that the stations located in the maximum eclipse cover zone exhibited notable decreases in TEC values. The minimum variation of about 11.76% in TEC values is observed at the station situating in about 20 percent eclipse cover zone, while it varies from 22% to 38% at the stations falling in about 60 percent eclipse cover zone. The highest variation in TEC values of about 44% is found at the stations in about 80 percent eclipse cover zone. The time of occurrence of maximum depletion in TEC values at each station is in line with their longitudinal sequence. Atmospheric gravity waves(AGWs) are also observed by performing wavelet analysis on TEC data. The global TEC maps visualize and confirm observed TEC variations, providing spatial and temporal insights into the ionospheric response. This analysis highlights the influence of station location and eclipse coverage on the magnitude and spatial distribution of TEC variations.

关键词： Solar eclipse Ionosphere GPS TEC AGW

Microstructure of TiAl alloy prepared by intense plastic deformation and subsequent reaction sintering

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中国有色金属学会会刊：英文版 2002年第4期12卷 621-624页

作者：李小强胡连喜王尔德贺文雄刘祖岩 department of Materials Science and Engineering Harbin Institute of Technol ogyHarbin 150001 China College of Mechanical Engineering South China University of Technology Guangzhou 510640 China department of Materials Science and Engineering Harbin Institute of Technol ogyHarbin 150001 China

TiAl alloy was prepared by intense plastic deformation and subsequent reaction sintering. The effect of plastic deformation on the microstructure of sintered TiAl alloy was investigated using energy dispersive X ray spectroscopy (EDS), optical microscopy and transmission electron microscopy (TEM). The results show that the intense plastic deformation of reacting Ti and Al phases caused by high energy ball milling refines the as sintered microstructure. The longer the milling time, the finer the grain size of γ and lamellar ( α 2 + γ ) phases. The finer grain size improves the properties of the TiAl alloy. It is also found that the volume fraction of lamellar ( α 2 + γ ) phases increases first, then decreases with increasing milling time. Based on the experimental results theoretical discussion was presented.

关键词： TiAl合金显微组织粉末冶金高能球磨感应烧结

Self-assembly of two pairs of homochiral M2L4 coordination capsules with varied confined space using Tr?ger's base ligands

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Chinese Chemical Letters 2025年第2期36卷 360-365页

作者： Yi Zhou Wei Zhang Rong Fu Jiaxin Dong Yuxuan Liu Zihang Song Han Han Kang Cai College of Chemistry Nankai University department of Chemistry Northwestern University department of Chemistry The University of Hong Kong

Chiral coordination molecular cages/capsules with discrete nanoconfined chiral cavities demonstrate significant potential applications across various fields. In this study, we utilized Tr?ger's base as the building block to design and synthesize two pairs of enantiopure ligands. These ligands were then self-assembled with Pd(II) ions through chiral self-sorting coordination, resulting in the formation of two pairs of homochiral M2L4-type coordination molecular capsules. Notably, due to differences in the substitution positions on the Tr?ger's base, these two pairs of enantiomeric coordination molecular capsules exhibited distinct levels of cavity closures, cavity sizes, and host-guest recognition properties. This research offers valuable insights into the construction of novel chiral molecular capsules and the regulation of confined cavities.

关键词： Chirality Host-guest recognition Metal-organic capsule Self-sorting Tröger's base

RGB Color-Discriminable Photonic Synapse for Neuromorphic Vision System

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Nano-Micro Letters 2025年第4期17卷 39-62页

作者： Bum Ho Jeong Jaewon Lee Miju Ku Jongmin Lee Dohyung Kim Seokhyun Ham Kyu-Tae Lee Young-Beom Kim Hui Joon Park department of Organic and Nano Engineering&Human-Tech Convergence Program Hanyang UniversitySeoul 04763Korea department of Semiconductor Engineering Hanyang UniversitySeoul 04763Korea department of Mechanical Engineering Hanyang UniversitySeoul 04763Korea department of Physics Inha UniversityIncheon 22212Korea

To emulate the functionality of the human retina and achieve a neuromorphic visual system,the development of a photonic synapse capable of multispectral color discrimination is of paramount ***,attaining robust color discrimination across a wide intensity range,even irrespective of medium limitations in the channel layer,poses a significant ***,we propose an approach that can bestow the color-discriminating synaptic functionality upon a three-terminal transistor flash memory even with enhanced discriminating *** incorporating the strong induced dipole moment effect at the excitation,modulated by the wavelength of the incident light,into the floating gate,we achieve outstanding RGB color-discriminating synaptic functionality within a remarkable intensity range spanning from 0.05 to 40 mW cm^(-2).This approach is not restricted to a specific medium in the channel layer,thereby enhancing its *** effectiveness of this color-discriminating synaptic functionality is demonstrated through visual pre-processing of a photonic synapse array,involving the differentiation of RGB channels and the enhancement of image contrast with noise ***,a convolutional neural network can achieve an impressive inference accuracy of over 94%for Canadian-Institute-For-Advanced-Research-10 colorful image recognition task after the *** proposed approach offers a promising solution for achieving robust and versatile RGB color discrimination in photonic synapses,enabling significant advancements in artificial visual systems.

关键词： Organic field-effect transistor Photonic synapse Excited-state dipole moment RGB color discrimination Neuromorphic visual system

Effects of rare-earth Pr3+-Dy3+ doping on structural,magnetic,optical and dielectric properties of Zn2Y hexaferrite

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Journal of Rare Earths 2025年第2期43卷 329-336页

作者： Ibrahim Mohammed Mohamed E.El Sayed Ali Shawabkeh Mohammad N.Murshed Ibtehaj F.Alshdoukhi Zeinhom M.El-Bahy J.Mohammed A.K.Srivastava department of Physics Lovely Professional University department of Science Technology Waziri Umaru Federal Polytechnic Birnin Kebbi Physics department Faculty of Science and ArtsKing Khalid University College of Engineering and Technology American University of the Middle East department of Basic Sciences College of Science and Health ProfessionsKing Saud Bin Abdulaziz University for Health ScienceKing Abdullah International Medical Research Center department of Chemistry Faculty of ScienceAl-Azhar University department of Physics Faculty of ScienceFederal University Dutse

This study was conducted to investigate the properties of Pr3+-Dy3+doped Zn2Y-type hexaferrite for potential technological applications.X-ray diffraction（XRD）,Fourier transform infrared spectroscopy（FTIR） and field-emission scanning electron microscopy（FESEM） were used to analyze structural *** crystallite size in the synthesized samples varies between 57.54 and 68.57 *** vibrational bands at 400 and 600 cm-1,common to all hexaferrites,were confirmed through *** FESEM analysis reveals an agglomeration of magnetic grains and a decrease in the average grain size from 1.24 to1.06 μ*** M-H loops show that,with x values of 0.0,0.1,and 0.2,the saturation magnetization is determined to be 34.76,34.23,and 32.52 emu/g,*** corresponding coercivity values are21.24,30.39,and 33.99 ***-visible spectroscopy using Tauc theory reveals an increase in the optical band gap from 2.32 to 2.50 eV,indicating a tunable energy band structure by incorporating Pr3+-Dy3+*** dielectric constant increases,whereas AC conductivity decreases with increased Pr3+-Dy3+*** obtained results suggest the potential suitability of these materials for various technological applications.

关键词： Dielectric constant Magnetic hysteresis Optical band gap Pr3+-Dy3+ Rare earths Zn2Y-type hexaferrite