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Small Solutions of Quadratic Equations with Prime Variables in Arithmetic Progressions

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Acta Mathematica Sinica,English Series 2009年第2期25卷 299-320页

作者： Tian ze wang School of Mathematics and Information Sciences He'nan University Kaifeng 475001 P. R. China School of Mathematics and Information Sciences North China University of Water Conservancy and Electric Power Zhengzhou 450011 P. R. China

A necessary and sufficient solvable condition for diagonal quadratic equation with prime variables in arithmetic progressions is given, and the best qualitative bound for small solutions of the equation is obtained,

关键词： quadratic equation prime variable small solution arithmetic progression

Failure behavior analysis of phased-mission systems considering functional and physical isolation effects

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Chinese Journal of Aeronautics 2022年第10期35卷 195-207页

作者： Ying CHEN ze wang Rui KANG School of Reliablility and Systems Engineering Beihang UniversityBeijing 100083China

Phased-Mission Systems(PMS)are widely applied in aerospace,telecommunication and intelligent systems for multiple,consecutive and non-overlapping phases of *** phasedependent stresses and system structure cause some difficulties to the reliability analysis of *** this paper,we analyze the physical isolation effects on the degradation speeds and across-phase damage accumulations of failure ***,some corresponding reliability and unreliability formulas are ***,a hierarchical Binary Decision Diagram(BDD)-based modeling method is proposed for incorporating functional and physical isolation effects into BDD models,and the analytical method with phase algebras is introduced for studying the failure behavior of PMS with functional *** the case study,we evaluate the collision avoidance system of a fixed-wing unmanned aerial vehicle as an example to demonstrate the proposed modeling and analysis *** show that the physical isolation effects have significant influences on the degradations of components,which deserves detailed analysis for a more practical and realistic PMS’s failure behavior.

关键词： Failure mechanism Phase-dependent damage accumulation Phase-dependent degradation Physical isolation effect Reliability evaluation

Hadronuclear interpretation of the possible neutrino emission from PKS B1424-418,GB6 J1040+0617 and PKS 1502+106

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Research in Astronomy and Astrophysics 2021年第12期21卷 375-382页

作者： ze-Rui wang Rui Xue College of Physics and Electronic Engineering Qilu Normal UniversityJinhua 321004China Department of Physics Zhejiang Normal UniversityJinan 250200China

In addition to neutrino event IceCube-170922 A which is observed to be associated with aγ-ray flare from blazar TXS 0506+056,there are also several neutrino events that may be associated with *** them,PKS B1424-418,GB6 J1040+0617 and PKS 1502+106 are low synchrotron peaked sources,which are usually believed to have the broad line region in the vicinity of the central black *** are considered as counterparts of IceCube event 35,IceCube-141209 A and IceCube-190730 A,*** considering the proton-proton(pp)interactions between the dense gas clouds in the broad line region and the relativistic protons in the jet,we show that the pp model that is applied in this work can not only reproduce the multi-waveband spectral energy distribution but also suggest a considerable annual neutrino detection *** also discuss the emission from the photopion production and Bethe-Heitler pair production with a sub-Eddington jet power that is suggested in our model and find that it has little effect on the spectrum of total emission for all of three sources.

关键词： neutrinos galaxies:active galaxies:jets radiation mechanisms:non-thermal

An explanation about the flat radio spectrum for Mrk 421

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Research in Astronomy and Astrophysics 2021年第4期21卷 311-318页

作者： Rui Xue ze-Rui wang Department of Physics Zhejiang Normal UniversityJinhua 321004China School of Astronomy and Space Science Nanjing UniversityNanjing 210093China

It is well known that a flat radio spectrum is a common property in the spectral energy distribution of *** one-zone leptonic models are generally successful in explaining the multi-wave band emission,they are problematic in reproducing the radio *** the study of Mrk 421,one-zone models suggest that in order to avoid overproducing the radio flux,the minimum electron Lorentz factor should be larger than a few hundred at least,even considering the synchrotron self-absorption *** result suggests that the model predicted spectral index in the radio band of Mrk 421 should be-1/*** the basis of this result,by assuming there is a neglected region that will also contribute the radio emission and its electron energy index naturally originates from the simplest first-order Fermi acceleration mechanism,we can get a superimposed flat radio *** this paper,a two-zone model is proposed to reproduce the quiescent state spectral energy distribution of Mrk *** addition to taking into account the emission from a conventional radiation zone,we further consider emission from the acceleration zone in which particles are accelerated at a shock *** the present model,our fitting result suggests that the low frequency flat radio spectrum of Mrk 421 might be explained as a superposition of the synchrotron emission from acceleration zone and radiation zone.

关键词： galaxies:active galaxies:jets radiation mechanisms:non-thermal

Characteristics of phosphorus fractionated from the sediment resuspension in abrupt expansion flow experiments

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Journal of Environmental Sciences 2010年第10期22卷 1519-1526页

作者： Jun Wan ze wang Hezhong Yuan . College of Environmental Science and Engineering Hohai University Nanjing 210098 China College of Water Conservancy and Hydropower Engineering Hohai University Nanjing 210098 China. State Key Laboratory of Lake Sediments Process Nanjing Institute of Geography and Limnology Chinese Academy of Sciences Nanjing 210098 China

Phosphorous （P） fraction characteristics in sediment resuspension were investigated under adequately hydrodynamic conditions. Four forms of P in overlying water, including dissolved inorganic P, dissolved total P, total P, and particulate P, and six fractions of P in suspended particulate matter （SPM）, including loosely sorbed P （NH4Cl-P）, redox-sensitive P （BD-P）, aluminum-bound P （Al- P）, organic P （NaOH-nrP）, calcium-bound P （Ca-P） and residual P （Res-P）, were quantified, respectively. Different hydrodynamic conditions resulted in different P form changes. Four states could be ascribed：（1） P desorption by sediment and SPM, and P adsorption by overlying water; （2） P desorption by SPM, and P adsorption by overlying water; （3） P adsorption by SPM, and P desorption by overlying water; and （4） P equilibrium between SPM and overlying water. The contents of P in overlying water acquired peak values in the middle position of the vertical P distribution due to the combined actions of SPM and sediment. P fractions in SPM were in the following order： BD-P 〉 NaOH-nrp 〉 Ca-P 〉 Al-P 〉 Res-P 〉 NH4Cl-P. BD-P in SPM frequently exchanged with P forms in overlying water. Resuspension was favorable to forming Ca-P in SPM.

关键词： phosphorus fractions hydrodynamic conditions suspended particulate matter abrupt expansion flow

Active feedback control of sound radiation in elastic wave metamaterials immersed in water with fluid-solid coupling

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Acta Mechanica Sinica 2021年第5期37卷 803-825,I0002页

作者： Zhi-Hua He Yi-ze wang Yue-Sheng wang Institute of Engineering Mechanics Beijing Jiaotong UniversityBeijing 100044China Department of Mechanics Tianjin UniversityTianjin 300350China

Due to their potential properties unlike traditional materials and structures,elastic wave metamaterials have received significant interests in recent *** the coupling between the acoustic and vibration,their mechanical characteristics can be tuned by the active feedback control system at low frequency ranges in which the traditional passive control is *** work illustrates that the superior performances of the effective mass density and sound pressure level(SPL)of an elastic wave metamaterial can be significantly changed by the active control,in which the periodic array of local resonators and orthogonal stiffeners are ***,based on the locally resonant mechanism,the negative density occurs over a frequency *** to the effects of lattice constant,structural damping and other parameters,the SPL with the function of fluid-solid coupling are illustrated and discussed.

关键词： Elastic wave metamaterial Local resonance Sound radiation Fluid-solid coupling Active feedback control

Sound Transmission Comparisons of Active Elastic Wave Metamaterial Immersed in External Mean Flow

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Acta Mechanica Solida Sinica 2021年第3期34卷 307-325页

作者： Zhi-Hua He Yi-ze wang Yue-Sheng wang Institute of Engineering Mechanics Beijing Jiaotong UniversityBeijing 100044China Department of Mechanics Tianjin UniversityTianjin 300350China

Using the active feedback control system on the elastic wave metamaterial,this research concentrates on the sound transmission with the dynamic effective *** metamaterial is subjected to an incident pressure and immersed in the external mean *** elastic wave metamaterial consists of double plates and the upper and lower four-link mechanisms are attached *** vertical resonator is attached by the active feedback control system and connected with two four-link *** on the dynamic equivalent method,the metamaterial is equivalent as a single-layer plate by the dynamic effective *** the coupling between the fluid and structure,the expression of the sound transmission loss(STL)is *** research shows the influence of effective mass density on sound transmission properties,and the STL in both modes can be tuned by the acceleration and displacement feedback *** addition,the dynamic response and the STL are also changed obviously by different values of structural damping,incident angle(i.e.,the elevation and azimuth angles)and Mach number of the external fluid with the mean flow *** results for sound transmission by two methods are compared,i.e.,the virtual work principle for double plates and the dynamic equivalent method corresponding to a single *** paper is expected to be helpful for understanding the sound transmission properties of both pure single-and double-plate models.

关键词： Elastic wave metamaterials Active feedback control Dynamic equivalent method Sound transmission External mean flow

Characterization and in-situ formation mechanism of tungsten carbide reinforced Fe-based alloy coating by plasma cladding

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International Journal of Minerals,Metallurgy and Materials 2018年第4期25卷 439-443页

作者： Mi-qi wang ze-hua Zhou Lin-tao Wu Ying Ding ze-hua wang College of mechanics and materials Hohai University

The precursor carbonization method was first applied to prepare W–C compound powder to perform the in-situ synthesis of the WC phase in a Fe-based alloy coating. The in-situ formation mechanism during the cladding process is discussed in detail. The results reveal that fine and obtuse WC particles were successfully generated and distributed in Fe-based alloy coating via Fe/W–C compound powders. The WC particles were either surrounded by or were semi-enclosed in blocky M7C3 carbides. Moreover, net-like structures were confirmed as mixtures of M23C6 and α-Fe; these structures were transformed from M7C3. The coarse herringbone M6C carbides did not only derive from the decomposition of M7C3 but also partly originated from the chemical reaction at the α-Fe/M23C6 interface. During the cladding process, the phase evolution of the precipitated carbides was WC → M7C3 → M23C6 ＋ M6C.

关键词： precursor carbonization tungsten carbide (WC) microstructure in-situ formation mechanism phase evolution

蛹虫草水提物影响人胃癌细胞BGC-823不同RCD通路的转录组分析

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食品工业科技 2025年第4期46卷 1-9页

作者：崔明琦于凯雯宋扬徐方旭王升厚王泽沈阳师范大学生命科学学院辽宁沈阳110034 辽宁省功能性蛹虫草重点实验室辽宁沈阳110034 沈阳师范大学实验教学中心辽宁沈阳110034

目的：基于转录组测序技术，分析预测蛹虫草（XG）水提物影响人胃癌细胞BGC-823生长活性的主要调节性细胞死亡（Regulated cell death，RCD）信号通路。方法：MTT法测定XG水提物对胃癌细胞增殖能力的影响，转录组测序分析显著差异基因及... 详细信息

目的：基于转录组测序技术，分析预测蛹虫草（XG）水提物影响人胃癌细胞BGC-823生长活性的主要调节性细胞死亡（Regulated cell death，RCD）信号通路。方法：MTT法测定XG水提物对胃癌细胞增殖能力的影响，转录组测序分析显著差异基因及其KEGG富集情况，获得凋亡、自噬、坏死性凋亡及铁死亡信号通路的hub基因（10个）。通过激光共聚焦、流式细胞术、qRT-PCR进一步验证XG水提物对胃癌细胞凋亡的诱导情况。结果：XG水提物对人胃癌细胞BGC-823生长活性的抑制作用具有剂量依赖特征。转录组测序共筛选到5885个差异表达基因，并在凋亡（P=0.001）及自噬（P=0.008）信号通路存在显著性富集，除铁死亡外，其它信号通路的hub基因的表达量均被显著性抑制，包括caspase依赖性凋亡信号通路的关键因子CASP3、CASP9、CASP7和APAF1，自噬小体形成相关的基因ULK1、ULK2、UVRAG、Atg14及Atg5。细胞学检测结果显示，胃癌细胞经XG水提物处理后呈典型的凋亡形态学特征，早期凋亡率为24.8%，细胞周期阻滞于G2/M期。qRT-PCR检测显示，BCL2、BCL2L1、CASP3、CASP9及XIAP的表达受到显著抑制（P<0.01），ENDOG和AIF表达量上调明显（P<0.01），与转录组测序结果一致。结论：蛹虫草主要通过Caspase非依赖性线粒体凋亡途径抑制人胃癌细胞BGC-823的生长活性，同时可以影响自噬等信号通路的激活，为蛹虫草在功能性食品的开发提供理论支持。

关键词：蛹虫草凋亡自噬坏死性凋亡铁死亡