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Concept modeling of tapered thin-walled tubes

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第1期10卷 44-53页

作者： Michael l.DAY Department of Mechanical Engineering University of Louisville

This paper presents a method to create concept models for the tapered thin-walled tubes using beam elements and spring *** concept tapered beam models with different taper angles and cross sections are compared with those detailed models through impact *** crash results are recorded and compared,and the relatively good agreement is achieved between these *** modeling steps are illustrated in detail,and a general concept modeling method for such thin-walled tubes is summarized and presented.

关键词： Tapered tube Concept model Axial crushing Impact analysis Beam element Spring element

Terahertz band simulations using two different radiative transfer models

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Science China Earth Sciences 2018年第10期61卷 1482-1490页

作者： linjun PAN Daren lü laboratory for Middle Atmosphere and Global Environment Observation Institute of Atmospheric Physics Chinese Academy of Sciences

A high-resolution dual-band terahertz(THz) radiometer was designed to measure vertical distributions of chemical elements in the middle atmosphere of the Tibetan Plateau. A forward simulation, which always should be conducted firstly for the development of a matching retrieval algorithm, has not been done before. We use two radiative transfer models, ARTS and AM, to simulate the water vapor, ozone and carbon monoxide spectra on the plateau based on the spectral design of the THz radiometer. The emission line characteristics of the three gases in this spectral band are identified. Reasons for the differences in the spectral simulations between the two models are analyzed for individual gases. The impact of several different spectral parameter settings on the simulations are evaluated through a series of sensitivity experiments. This study suggests that the ARTS is more suitable for the development of the THz radiometer retrieval algorithm. An optimal parameter setting of the ARTS for the three elements are given.

关键词： Terahertz radiation Radiometer Radiative transfer model Spectral simulation Plateau

Coercivity mechanisms in nanostructured permanent magnets

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Chinese Physics B 2019年第7期28卷 1-13页

作者： G P Zhao l Zhao l C Shen J Zou l Qiu College of Physics and Electronic Engineering & Institute of Solid State Physics Sichuan Normal UniversityChengdu 610066 China State Key luboratory of Metastablc Materials Science and Technology Yunshnn University.Qinhuangdao 066004China Collaborative Innovation Center for Shunxi Advanced Permanent Materials and Technology Lint'en 041004 China

Coercivity mechanism in permanent magnets has been debated for many *** this paper, various models of the coercivity mechanism are classified and re-examined by the comparison and *** rotation and curling models can reveal the underlying reversal mechanism clearly based on isolated grains with elliptic *** contrast, the numerical methods consider inter-grain interactions while simulating the evolution of the spins and hysteresis loops with complicated ***, an exact simulation of magnetic reversal in permanent nanomagnets requires many meshes to mimic the thin domain wall *** and pinning are the two main coercivity mechanisms in permanent *** former signifies the beginning of the magnetic reversal, whilst the latter completes ***, it is proposed that the large difference between the intrinsic magnetic properties of the nucleation centers and those of the main phase can result in a large pinning field(self-pinning), which has the attributes of both traditional nucleation and *** a pinning explains the experimental data of permanent magnets very well, including the enhancement of the coercivity by the grain boundary pinning.

关键词： coercivity mechanism permanent nanomagnets self-pinning

Genome-wide association mapping in a sweet cherry germplasm collection(Prunus avium l.)reveals candidate genes for fruit quality traits

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Horticulture Research 2023年第10期10卷 227-249页

作者： Armel S.l.Donkpegan Anthony Bernard Teresa Barreneche José Quero-García Hélène Bonnet Mathieu Fouché loïck le Dantec Bénédicte Wenden Elisabeth Dirlewanger UMR BFP INRAEUniversity of Bordeaux71 Avenue Edouard BourlauxF-33882 Villenave d’OrnonFrance UMR BOA SYSAAFCentre INRAE Val de Loire37380 NouzillyFrance

In sweet cherry(Prunus avium l.),large variability exists for various traits related to fruit *** is a need to discover the genetic architecture of these traits in order to enhance the efficiency of breeding strategies for consumer and producer *** this objective,a germplasm collection consisting of 116 sweet cherry accessions was evaluated for 23 agronomic fruit quality traits over 2-6 years,and characterized using a genotyping-by-sequencing *** SNP coverage collected was used to conduct a genome-wide association study using two multilocus models and three reference *** identified numerous SNP-trait associations for global fruit size(weight,width,and thickness),fruit cracking,fruit firmness,and stone size,and we pinpointed several candidate genes involved in phytohormone,calcium,and cell wall ***,we conducted a precise literature review focusing on the genetic architecture of fruit quality traits in sweet cherry to compare our results with potential colocalizations of marker-trait *** study brings new knowledge of the genetic control of important agronomic traits related to fruit quality,and to the development of marker-assisted selection strategies targeted towards the facilitation of breeding efforts.

关键词： breeding germplasm traits

卵黄高磷蛋白α-淀粉酶抑制肽的制备、鉴定及酶抑制动力学分析

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食品工业科技 2025年第1期46卷 152-162页

作者：薛天睿吕彬斐张铭冉李灿张晓维天津科技大学食品科学与工程学院天津300457

为探索卵黄高磷蛋白肽(phosvitin phosphopeptide,PPP)对α-淀粉酶的抑制作用,使其能够调控血糖水平从而缓解Ⅱ型糖尿病,本研究以α-淀粉酶抑制率为指标酶解卵黄高磷蛋白制备PPP,利用酶抑制动力学实验分析PPP对α-淀粉酶的抑制类型,采... 详细信息

为探索卵黄高磷蛋白肽(phosvitin phosphopeptide,PPP)对α-淀粉酶的抑制作用,使其能够调控血糖水平从而缓解Ⅱ型糖尿病,本研究以α-淀粉酶抑制率为指标酶解卵黄高磷蛋白制备PPP,利用酶抑制动力学实验分析PPP对α-淀粉酶的抑制类型,采用液质联用鉴定后用分子对接筛选出高活性的α-淀粉酶抑制肽,最后验证其活性。结果表明,最优酶解条件为先经胰蛋白酶(加酶量7000 U/g)再经胃蛋白酶(加酶量60000 U/g)分别酶解6 h,制得的PPP在浓度7.81×10-3 mg/ml时具有最高α-淀粉酶抑制率70.69%±1.71%。PPP对α-淀粉酶的抑制类型为混合型抑制。鉴定筛选出了两种新型的高活性α-淀粉酶抑制肽FGTEPDAK和IWGR,经验证其IC50值分别为(0.80±0.14)×10-3 mg/ml和(1.80±0.31)×10-3 mg/ml,极显著低于阳性对照阿卡波糖(3.17±0.47)×10-3 mg/ml(P<0.01)。本研究揭示PPP可作为新型降糖物质,应用于缓解Ⅱ型糖尿病的功能性食品开发中。

关键词：卵黄高磷蛋白肽复合酶解 α-淀粉酶抑制剂分子对接酶抑制动力学

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A theoretical investigation of the band alignment of type-I direct band gap dilute nitride phosphide alloy of GaN_xAs_yP_(1-x-y)/GaP quantum wells on GaP substrates

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Chinese Physics B 2014年第7期23卷 640-644页

作者： O l nsal B Gnül M Temiz Department of Engineering Physics University of Gaziantep

The GaP-based dilute nitride direct band gap material Ga（NAsP） is gaining importance due to the monolithic integra- tion of laser diodes on Si microprocessors. The major advantage of this newly proposed laser material system is the small lattice mismatch between GaP and Si. However, the large threshold current density of these promising laser diodes on Si substrates shows that the carrier leakage plays an important role in Ga（NAsP）/GaP QW lasers. Therefore, it is necessary to investigate the band alignment in this laser material system. In this paper, we present a theoretical investigation to optimize the band alignment of type-I direct band gap GaNxAsyP1-x-y/GaP QWs on GaP substrates. We examine the effect of nitrogen （N） concentration on the band offset ratios and band offset energies. We also provide a comparison of the band alignment of type-I direct band gap GaNxAsyP1-x-y/GaP QWs with that of the GaNxAsyP1-x-y/Al2Ga1-2P QWs on GaP substrates. Our theoretical calculations indicate that the incorporations of N into the well and AI into the barrier improve the band alignment compared to that of the GaAsP/GaP QW laser heterostructures.

关键词： quantum well band alignment carrier confinement dilute nitride phosphide alloy

Exact Travelling Wave Solutions of Discrete Planar Velocity Boltzmann Models

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Chinese Physics letters 1997年第8期14卷 561-564页

作者： lÜ Xian-qing Department of Applied Mathematics Tsinghua UniversityBeijing 100084

By investigating the discrete planar Boltzmann models:the square 4-velocity and the hexagonal 6-velocity models,exact travelling wave solutions can be studied in a concise *** their exact travelling wave solutions can only be monotonic travelling *** conclusions of the precursors need *** suggests a general method for obtaining nontrivial exact solutions for the similar discrete Boltzmann equation.

关键词： equation. wave. travelling

Dynamic heating and thermal destruction conditions of quartz particles in polydisperse plasma flow of RF-ICP torch system

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Plasma Science and Technology 2020年第11期22卷 114-126页

作者： l MIAO Yu M GRISHIN Department of Thermophysics Moscow State Technical University N E BaumanMoscow 105005Russia

Numerical simulation of turbulent mixing process of polydisperse quartz particle(particle size distribution in the range of 0.1-0.4 mm)flow with Ar and Ar-H2 plasma generated by radio frequency inductively coupled plasma(RF-ICP)torch has been *** approximate two-stage approach has been proposed to calculate the spatial-temporal distributions of temperature and resulting thermal stress in quartz particles during dynamic heating in polydisperse plasma *** influence of working gas compositions,particle size distributions,injection angle and flow rate of carrier gas on the thermal destruction conditions of quartz particles has been determined under different particle feed *** is found that all the solid quartz particles(0.1-0.4 mm)could be thermal destructed without overheating in RF-ICP torch system,when the hydrogen volume fraction in working gases is more than 1.5%-2%and particle feed rate is in a certain *** values of the maximum and minimum feed rates have been determined under different hydrogen volume *** optimal particle injection angle and flow rate of carrier gas is found around 50°-60°and 160-220 slpm,under which the value of maximum equivalent thermal stress in quartz particles is highest.

关键词： RF-ICP torch dynamic heating thermal destruction hydrogen volume fraction optimal injection conditions

Evaluating the impact of thermostat control strategies on the energy flexibility of residential buildings for space heating

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Building Simulation 2021年第5期14卷 1439-1452页

作者： Kun Zhang Michaël Kummert Department of Mechanical Engineering Polytechnique MontrealMontrealCanada

Buildings can be operated in an energy-flexible manner while respecting occupant thermal *** energy flexibility of building operations,both in time and quantity,can be harnessed by the electrical grid for load *** the context of smart grid and intelligent buildings,the concept of energy flexibility in buildings broadens the existing demand management thinking from the top-down one-way control to two-way *** paper,extending studies on thermostat controls of heating and air conditioning systems for demand response,evaluates the impact of different control schemes on the energy flexibility of residential *** control strategies,Model Predictive Control(MPC)and Rule-Based Control(RBC),are investigated for a space heating system using co-simulation *** indicators are introduced and adapted from the literature to assess the control performances of the *** results show that different flexibility indicators favour different control strategies in this case *** demand response events of four hours,the MPC strategy presents two to three times of flexible energy than that of *** also delivers 20%more of maximum power reduction during the events against *** RBC strategy,on the other hand,is twice of MPC for flexible energy *** evaluation work can be beneficial to guide the control system design of new buildings or control retrofits of existing buildings that consider better grid-building interactions for the future.

关键词： energy flexibility MPC grid-building interaction demand response