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Influence of nitrogen status on fermentation performances of non-Saccharomyces yeasts:a review

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Food Science and Human Wellness 2024年第2期13卷 556-567页

作者： Jinchen Li Mengmeng Yuan Nan Meng Hehe Li Jinyuan Sun Baoguo Sun key laboratory of Brewing Molecular Engineering of China Light Industry Beijing Key Laboratory of Flavor ChemistryBeijing Technology&Business UniversityBeijing 100048China

Nitrogen,one of the most crucial nutrients present in grapes and musts,plays a key role in yeast activities during alcoholic *** influences are imposed on yeast growth and fermentation performances including the formation of secondary *** cerevisiae,the main yeast responsible for fermentation,has been studied extensively regarding nitrogen *** the other hand,a similar study for non-Saccharomyces yeasts,whose contributions to winemaking have gradually been acknowledged,remains to be fully explored,with a few studies being *** review starts by discussing nitrogen impacts on non-Saccharomyces yeast growth and fermentation kinetics in different case scenarios,then proceeds to summarize the nitrogen preferences of individual yeast strains with regulation mechanisms elucidated by recent *** discussions on the influences on the production of volatile compounds and proposed pathways therein are made,followed by future work suggested as the final *** summarizing the nitrogen impacts on non-Saccharomyces yeasts throughout alcoholic fermentation,this review will be helpful in obtaining a more comprehensive view on these non-conventional wine yeasts in terms of nutrient requirements and corresponding volatile *** gaps will therefore be elucidated for future research.

关键词： Non-Saccharomyces yeasts Nitrogen Fermentation kinetics Nitrogen preference Wine aroma

Effects of projectile parameters on the momentum transfer and projectile melting during hypervelocity impact

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Defence technology（防务技术） 2024年第2期32卷 89-103页

作者： Wenjin Liu Qingming Zhang Renrong Long Zizheng Gong Ren Jiankang Xin Hu Siyuan Ren Qiang Wu Guangming Song State key laboratory of Explosion Science and technology Beijing Institute of TechnologyBeijing100081China beijing Institute of Spacecraft Environment Engineering China Academy of Space TechnologyBeijing100094China

The effects of projectile/target impedance matching and projectile shape on energy,momentum transfer and projectile melting during collisions are investigated by numerical *** comparing the computation results with the experimental results,the correctness of the calculation and the statistical method of momentum transfer coefficient is *** shapes of aluminum,copper and heavy tungsten alloy projectiles striking aluminum,basalt,and pumice target for impacts up to 10 km/s are *** influence mechanism of the shape of the projectile and projectile/target density on the momentum transfer was *** an increase in projectile density and length-diameter ratio,the energy transfer time between the projectile and targets is *** projectile decelerates slowly,resulting in a larger cratering *** energy consumed by the projectile in the excavation stage increased,resulting in lower mass-velocity of ejecta and momentum transfer *** numerical simulation results demonstrated that for different projectile/target combinations,the higher the wave impedance of the projectile,the higher the initial phase transition velocity and the smaller the mass of phase *** results can provide theoretical guidance for kinetic impactor design and material selection.

关键词： Hypervelocity impact Energy partitioning Impact melting Momentum transfer

Determining an optimal control strategy for anthropogenic VOC emissions in China based on source emissions and reactivity

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Journal of Environmental Sciences 2024年第2期136卷 248-260页

作者： Ruipeng Wang Xiaoqi Wang Shuiyuan Cheng Jiaxian Zhu Xinyu Zhang Long Cheng Kai Wang key laboratory of beijing on Regional Air Pollution Control Faculty of Environment and LifeBeijing University of TechnologyBeijing 100124China

An evidence-based control strategy for emission reduction of VOC sources can effectively solve the regional PM2.5and O3compound pollution in *** estimated the anthropogenic VOC emission inventory in China in 2018 and established a source profile database containing 129 sources based on localized detection and the latest research ***,the distribution of the ozone formation potential(OFP)and secondary organic aerosol formation potential(SOAFP)for emission sources was ***,priority control routes for VOC emission sources were proposed for different *** VOC emissions in China reached 27,211.8 Gg in 2018,and small passenger cars,industrial protective coatings,biomass burning,heavy trucks,printing,asphalt paving,oil storage and transportation,coking,and oil refining were the main *** protective coatings,small passenger cars,and biomass burning all contributed significantly to OFP and *** in emission reduction control should be given to industrial protective coatings,small passenger cars,heavy trucks,coking,printing,asphalt paving,chemical fibers,and basic organic chemical sources over the medium and long term in *** addition,the priority control route for VOC emission sources should be adjusted according to the variations in VOC emission characteristics and regional differences,so as to obtain the maximum environmental benefits.

关键词： Volatile organic compounds Anthropogenic emission inventory Reactivity Emission projection Priority control route

A novel optical emission spectroscopy method for diagnostics of contribution of different ionization mechanisms and flux of ions in different valences in discharge channel of a Hall thruster

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Chinese Journal of Aeronautics 2024年第4期37卷 294-307页

作者： Yanfei WANG Ximing ZHU Renqiu ZOU Shilin YAN Junwei JIA Zhongxi NING Daren YU School of Energy Science and Engineering Harbin Institute of TechnologyHarbin 150001China key laboratory of Aerospace Plasma Propulsion Ministry of Industry and Information TechnologyHarbin 150001China beijing Orient Institute of measurement and Test Beijing 100094China beijing Aerospace Long March Aircraft Research Institute Beijing 100076China

The mass application of Hall thrusters poses the need for a diagnostic method of ionization mechanism in the discharge channel to boost the iteration and optimization of thruster *** work presents an Optical Emission Spectroscopy (OES) method for diagnostics of the contribution of different ionization mechanisms and the flux of ions in different valences in the discharge channel of a Hall *** emission spectra in the discharge channel are analyzed by jointly utilizing a collisional-radiative model,an ionization-excitation model,and a flux-conservation *** is found that the intensities of some spectral lines can be converted into the reaction rates of collision processes,e.g.,electron-induced excitation and ionization *** latter can further be used to determine the evolutions of particle fluxes by utilizing the conservation law of *** novel method is demonstrated on a kilo-watt Hall *** evolutions of several parameters are determined using this method along the discharge channel,including the ionization rates of different mechanisms,particle fluxes,particle densities,and particle *** novel method can be further developed by being jointly utilized with spectral imaging and tomography techniques,enabling diagnostics of multi-dimensional distributions of the above-mentioned parameters in the discharge channel and near-field plume.

关键词： Hall thruster Optical emission spectroscopy Ionization mechanism Particle flux Divalent ion

In situ luminescence measurements of GaN/Al_(2)O_(3) film under different energy proton irradiations

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Chinese Physics B 2024年第5期33卷 704-710页

作者：蒋文丽欧阳潇仇猛淋英敏菊陈琳庞盼张春雷张耀锋廖斌 key laboratory of Beam technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation technology Beijing Academy of Science and TechnologyBeijing 100875China

Ion beam-induced luminescence(IBIL) experiments were performed to investigate the in situ luminescence of GaN/Al_(2)O_(3) at varying ion energies,which allowed for the measurement of defects at different depths within the *** energies of H^(+)were set to 500 keV,640 keV and 2 MeV,the Bragg peaks of which correspond to the GaN film,GaN/Al_(2)O_(3) heterojunction and Al_(2)O_(3) substrate,respectively.A photoluminescence measurement at 250 K was also performed for comparison,during which only near band edge(NBE) and yellow band luminescence in the GaN film were *** evolution of the luminescence of the NBE and yellow band in the GaN film was discussed,and both exhibited a decrease with the fluence of H^(+).Additionally,the luminescence of F centers,induced by oxygen vacancies,and Cr^(3+),resulting from the ^(2)E →^(4)A_(2) radiative transition in Al_(2)O_(3),were measured using 2 MeV H^(+).The luminescence intensity of F centers increases gradually with the fluence of H^(+).The luminescence evolution of Cr^(3+)is consistent with a yellow band center,attributed to its weak intensity,and it is situated within the emission band of the yellow band in the GaN *** results show that IBIL measurement can effectively detect the luminescence behavior of multilayer films by adjusting the ion *** measurement can be excited by various techniques,but IBIL can satisfy in situ luminescence measurement,and multilayer structural materials of tens of micrometers can be measured through IBIL by adjusting the energy of the inducing *** evolution of defects at different layers with ion fluence can be obtained.

关键词： ion beam-induced luminescence(IBIL) GaN/Al_(2)O_(3) ion beam

Electronic structure engineering of single atomic sites by plasmoninduced hot electrons for highly efficient and selective photocatalysis

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Nano Research 2024年第8期17卷 6960-6967页

作者： Xiaoya Huang Xinyuan Li Akang Chen Hongfei Gu Shouyuan Li Tailei Hou Shuwen Zhu Shuang Yu Yin Song Jiatao Zhang beijing key laboratory of Construction Tailorable Advanced Functional Materials and Green Applications MIIT Key Laboratory of Medical Molecule Science and Pharmaceutical EngineeringMOE Key Laboratory of Cluster ScienceSchool of Chemistry and Chemical EngineeringSchool of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China MIIT key laboratory of Complex-field Intelligent Exploration School of Optics and PhotonicsBeijing Institute of TechnologyBeijing 100081China

Single atom(SA)catalysts have achieved great success on highly selective heterogeneous catalysis due to their abundant and homogeneous active *** electronic structures of these active sites,restrained by their localized coordination environments,significantly determine their catalytic performances,which are difficult to ***,we investigated the effect of localized surface plasmon resonance(LSPR)on engineering the electronic structures of single atomic ***,core–shell structures consisted of Au core and transition metal SAs loaded N-doped carbon(CN)shell were constructed,namely Au@M-SA/CN(M=Ni,Fe,and Co).It was demonstrated that plasmon-induced hot electrons originated from Au were directionally injected to the M-SAs under visible light irradiation,which significantly changed their electronic structures and meanwhile facilitated improved overall charge separation *** as-prepared Au@Ni-SA/CN exhibited highly efficient and selective photocatalytic CO_(2) reduction to CO performance,which is 20.8,17.5,and 6.9 times those of Au nanoparticles,Au@CN,and Ni-SA/CN,*** spectroscopy analysis and theoretical calculations confirmed that the plasmon enhanced Ni-SA/CN sites featured increased charge density for efficient intermediate activation,contributing to the superb photocatalytic *** work provides a new insight on plasmon and atomic site engineering for efficient and selective catalysis.

关键词： single atom catalysts plasmon enhancement coupling effect photocatalysis CO_(2) reduction

High-Efficiency Dynamic Terahertz Deflector Utilizing a Mechanically Tunable Metasurface

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Research 2024年第3期2023卷 585-594页

作者： Zhenci Sun Chao Liang Chen Chen Xiayu Wang Enze Zhou Xiaomeng Bian Yuanmu Yang Rui You Xiaoguang Zhao Jiahao Zhao Zheng You Department of Precision Instrument Tsinghua UniversityBeijing 100084China State key laboratory of Precision measurement technology and Instruments Tsinghua UniversityBeijing 100084China beijing Advanced Innovation Center for Integrated Circuits Beijing 100084China School of Instrument Science and Opto-Electronic Engineering Beijing Information Science and Technology UniversityBeijing 100016China.

Terahertz (THz) wave manipulation, especially the beam deflection, plays an essential role in various applications, such as next-generation communication, space exploration, and high-resolution imaging. Current THz optical components and devices are hampered by their large bulk sizes and passive responses, limiting the development of high-performance, miniaturized THz microsystems. Tunable metasurfaces offer a powerful dynamic optical platform for controlling the propagation of electromagnetic waves. In this article, we presented a mechanically tunable metasurface (MTM), which can achieve terahertz beam deflection and vary the intensity of the anomalous reflected terahertz wave by changing the air gap between the metallic resonator (MR) array with phase discontinuities and Au ground plane. The absence of lossy spacer materials substantially enhances deflection efficiency. The device was fabricated by a combination of the surface and bulk-micromachining processes. The THz beam steering capability was characterized using terahertz time domain spectroscopy. When the air gap is 50 μm, the maximum deflection coefficient reaches 0.60 at 0.61 THz with a deflection angle of ~44.5°, consistent with theoretical predictions. We further established an electrically tunable miniaturized THz device for dynamic beam steering by introducing a micro voice coil motor to control the air gap continuously. It is shown that our designed MTM demonstrates a high modulation depth of deflection coefficient (~ 62.5%) in the target steered angle at the operating frequency. Our results showcase the potential of the proposed MTM as a platform for high-efficiency THz beam manipulation.

关键词： tunable Efficiency resonator

Isomeric fluorescence sensors for wide range detection of ionizing radiations

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Defence technology（防务技术） 2024年第4期34卷 247-257页

作者： Jimin Han Tianyu Yang Li Yang Yuanjian Li State key laboratory of Explosion Science and technology of China Beijing Institute of TechnologyBeijing 100081China Chongqing Innovation Center Beijing Institute of TechnologyChongqing 401120China

In order to achieve a wider range of ionizing radiations detection,novel fluorescence sensing materials have been developed that utilize the fluorescence enhancement phenomenon caused by the intramolecular photoinduced electron transfer(PET)*** perylene diimide isomers PDI-P and PDI-B were designed and synthesized,and their molecular structures were characterized by high-resolution Fourier transform mass spectrometry(HRMS),nuclear magnetic resonance hydrogen and carbon spectroscopy(~1H and~(13)C NMR).The interaction between ionizing radiation and fluorescent molecules was simulated by HCl *** results show that combining PDIs and HCl can improve fluorescence through the retro-PET *** the similarities in chemical structures,the fluorescent enhancement multiple of PDI-B with aromatic amine as electron donor is much higher than that of PDI-P with alkyl *** the direct irradiation experiments of ionizing radiation,the emission enhancement multiples of PDI-P and PDI-B are 2.01 and 45.4,***,density functional theory(DFT)and time-dependent density functional theory(TDDFT)calculations indicate that the HOMO and HOMO-1 energy ranges of PDI-P and PDI-B are 0.54 e V and 1.13 e V,respectively.A wider energy range has a stronger driving force on electrons,which is conducive to fluorescence *** femtosecond transient absorption spectroscopy(fs-TAS)and transient fluorescence spectroscopy(TFS)tests show that PDI-B has shorter charge separation lifetime and higher electron transfer rate *** both isomers can significantly reduce LOD during PET process,PDI-B with aromatic amine has a wider detection range of 0.118—240 Gy due to its larger emission enhancement,which is a leap of three orders of *** breaks through the detection range of gamma radiation reported in existing studies,and provides theoretical support for the further study of sensitive and effective new materials for ionizing radiation dete

关键词： Perylene imide Intramolecular PET Ionizing radiation detection Fluorescence sensor Isomers

Study of primordial deuterium abundance in Big Bang nucleosynthesis

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Nuclear Science and Techniques 2024年第3期35卷 208-215页

作者： Zhi-Lin Shen Jian-Jun He key laboratory of Beam technology of Ministry of Education College of Nuclear Science and TechnologyBeijing Normal UniversityBeijing 100875China Institute of Radiation technology Beijing Academy of Science and TechnologyBeijing 100875China

Big Bang nucleosynthesis(BBN)theory predicts the primordial abundances of the light elements^(2) H(referred to as deuterium,or D for short),^(3)He,^(4)He,and^(7) Li produced in the early *** these,deuterium,the first nuclide produced by BBN,is a key primordial material for subsequent *** date,the uncertainty in predicted deuterium abundance(D/H)remains larger than the observational *** this study,the Monte Carlo simulation code PRIMAT was used to investigate the sensitivity of 11 important BBN reactions to deuterium *** found that the reaction rate uncertainties of the four reactions d(d,n)^(3)He,d(d,p)t,d(p,γ)^(3)He,and p(n,γ)d had the largest influence on the calculated D/H ***,the calculated D/H uncertainty cannot reach observational precision even with the recent LUNA precise d(p,γ)^(3) He *** the nuclear physics aspect,there is still room to largely reduce the reaction-rate uncertainties;hence,further measurements of the important reactions involved in BBN are still necessary.A photodisintegration experiment will be conducted at the Shanghai Laser Electron Gamma Source Facility to precisely study the deuterium production reaction of p(n,γ)d.

关键词： Big Bang nucleosynthesis Abundance of deuterium Reaction cross section Reaction rate Monte Carlo method