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梅花花色与黄酮类成分相关性及ISSR种质资源遗传多样性分析

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中草药 2024年第10期55卷 3457-3468页

作者：唐志康钟秀美杨雯戴明月潘开东何三健舒晓燕张文侯大斌陈平西南科技大学生命科学与工程学院四川绵阳621010 达州市达川区茶果站四川达川635000

目的研究梅Prunus mume的花色及花中黄酮类成分特征,揭示其遗传多样性及亲缘关系,为梅种质资源鉴定和新品种培育提供依据。方法以52份梅花样品为材料,分别采用红绿蓝(red green blue,RGB)色值法和化学法调查花色特征,采用高效液相色谱法... 详细信息

目的研究梅Prunus mume的花色及花中黄酮类成分特征,揭示其遗传多样性及亲缘关系,为梅种质资源鉴定和新品种培育提供依据。方法以52份梅花样品为材料,分别采用红绿蓝(red green blue,RGB)色值法和化学法调查花色特征,采用高效液相色谱法(HPLC)评估梅花的6种黄酮类成分特征,利用ISSR分子标记技术探究梅的遗传多样性。结果RGB色值和亮度指数表明“乌梅帝”花色最暗,种质资源圃花色最亮。“乌梅帝”植株和“乌梅后”植株花均含有6种黄酮,部分“乌梅帝”和“乌梅后”区域梅花则未检测出金丝桃苷、山柰酚及异鼠李素。尽管主成分及相关分析结果表明梅花色与其黄酮的含量无内在关系,但其成分间存在相关性,梅花的异槲皮素与芦丁和金丝桃苷含量呈显著正相关,异槲皮素与槲皮素呈显著正相关。槲皮素与山柰酚和异鼠李素呈显著正相关,山柰酚与异鼠李素呈显著正相关。ISSR标记结果表明3个调查区域间存在着亲缘关系,资源圃部分植株可能源自“乌梅帝”和“乌梅后”区,“乌梅后”和“乌梅帝”区存在相互移栽的情况。结论基于RGB色值法和化学法预测梅花黄酮含量仍有待优化,但进化树可将“乌梅帝”及“乌梅后”准确聚类。ISSR分子标记结果证实“乌梅帝”“乌梅后”及资源圃植株的亲缘关系,梅在群体水平上遗传多样性较高,且各调查区域间存在频繁遗传交流。

关键词：梅花色黄酮遗传多样性种质资源 ISSR 金丝桃苷山柰酚异鼠李素

A head-mounted photoacoustic fiberscope for hemodynamic imaging in mobile mice

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Light(Science & Applications) 2024年第6期13卷 1012-1014页

作者： xiaoyan Zheng shuai Na National Biomedical Imaging Center College of Future TechnologyPeking UniversityBeijing100871China Academy for Advanced Interdisciplinary Studies Peking UniversityBeijing100871China

A miniaturized photoacoustic fiberscope has been developed, featuring a lateral resolution of 9 microns and a lightweight design at 4.5 grams. Engineered to capture hemodynamic processes at single-blood-vessel resolution at a rate of 0.2 Hz, this device represents an advancement in head-mounted tools for exploring intricate brain activities in mobile animals.

关键词： fiber mobile Engine

Meridional deflection of global eddy propagation derived from tandem altimetry: Mechanism and implication

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Science China Earth Sciences 2024年第3期67卷 811-825页

作者： Ge CHEN xiaoyan CHEN Frontiers Science Center for Deep Ocean Multispheres and Earth System School of Marine TechnologyOcean University of ChinaQindao 266100China Laboratory for Regional Oceanography and Numerical Modeling Laoshan LaboratoryQindao 266237China

A common view on meridional deflection of eddy propagation is poleward for cyclones and equatorward for anticyclones. This widely accepted polarity-sensitive pattern has been increasingly undermined given that it is systematically violated on both zonal and regional scales as recently reported. Here, we approach the problem by exploring these violations in terms of eddy effects of spatiotemporal geostrophy, thermal fading, and flow dragging, yielding the following main conclusions.(1) The polarity-dependent deflection discrepancy is a pseudo feature resulting from a biased fit to the normalized eddy tracks which are spatially asymmetric(though azimuthally symmetric) between the two signs;Instead, the primary pattern of eddy deflection appears to be geographically correlated and polarity independent.(2) Geostrophic adjustment plays a critical role in defining the meridional movement of an eddy. Specifically, a consistent poleward(equatorward) trajectory bending of spatially(temporally) ageostrophic eddies is observed irrespective of their polarity.(3) The mechanism of eddy deflection is also determined by its zonal propagation direction. Westward propagating eddies are substantially affected by thermal fading, while opposite ones by flow dragging. A realistic and comprehensive understanding of eddy deflection mechanisms serves as a significant contribution to the prediction of eddy trajectory, and the protection of ocean environment.

关键词： Mesoscale eddies Eddy propagation Eddy meridional deflection Satellite observation Geostrophic adjustment

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Physics-Informed Neural Networks with Two Weighted Loss Function Methods for Interactions of Two-Dimensional Oceanic Internal Solitary Waves

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Journal of Systems Science & Complexity 2024年第2期37卷 545-566页

作者： SUN Junchao CHEN Yong TANG xiaoyan School of Mathematical Sciences Key Laboratory of Mathematics and Engineering Applications(Ministry of Education)&Shanghai Key Laboratory of PMMPEast China Normal UniversityShanghai 200241China College of Mathematics and Systems Science Shandong University of Science and TechnologyQingdao 266590China

The multiple patterns of internal solitary wave interactions(ISWI)are a complex oceanic *** remote sensing techniques indirectly detect these ISWI,but do not provide information on their detailed structure and ***,the authors considered a three-layer fluid with shear flow and developed a(2+1)Kadomtsev-Petviashvili(KP)model that is capable of describing five types of oceanic ISWI,including O-type,P-type,TO-type,TP-type,and *** learning models,particularly physics-informed neural networks(PINN),are widely used in the field of fluids and internal solitary ***,the authors find that the amplitude of internal solitary waves is much smaller than the wavelength and the ISWI occur at relatively large spatial scales,and these characteristics lead to an imbalance in the loss function of the PINN *** solve this problem,the authors introduce two weighted loss function methods,the fixed weighing and the adaptive weighting methods,to improve the PINN *** successfully simulated the detailed structure and dynamics of ISWI,with simulation results corresponding to the satellite *** particular,the adaptive weighting method can automatically update the weights of different terms in the loss function and outperforms the fixed weighting method in terms of generalization ability.

关键词： Internal solitary wave interactions KP equation PINN method weighted loss function method

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Helium ion irradiation effects on neodymium and cerium co-doped Gd_2Zr_2O_7 pyrochlore ceramic

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Journal of Rare Earths 2018年第4期36卷 398-403页

作者： Qijun Hu Junsen Zeng Lan Wang xiaoyan shu Dadong Shao Haibin Zhang Xirui Lu School of Civil Engineering and Architecture Southwest Petroleum University Fundamental Science on Nuclear Wastes and Environmental Safety Laboratory Southwest University of Scienoe and Technology Institute of Plasma Physics Chinese Academy of Sciences Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics

This paper studies the helium ions irradiation effects on Nd and Ce co-doped Gd_2 Zr_2 O_7 ceramics. where Nd replaces the Gd site and Ce replaces the Zr site respectively. A series of（Gd_（1-x）Nd_x）_2（Zr_（1-y）Ce_y）_2 O_7（0 ≤ x, y ≤ 1） ceramics were irradiated with a 500 keV He ions at room temperature at fluences ranging from 1 × 10^（15） to 1 × 10^（17） ions/cm^2. The irradiated samples were characterized using GIXRD, Raman and SEM measurements. From the GIXRD and Raman observations, the results indicate that all the samples display a deficient fluorite structure after irradiation. The irradiation toleration increases with the irradiation depth increasing under experimental conditions, and Nd_2 Ce_2 O_7 has the best irradiation stability in the（Gd_（1-x）Nd_x）_2（Zr_（1-y）Ce_y）_2 O_7（0≤ x. y≤1）. Based on SEM results, the irradiated samples are still relatively dense and uniform, and no second phase exists.

关键词： Helium ion irradiation Ceramic Pyrochlore Co-doping Rare earths

Tailoring the Properties of Polyhydroxyalkanoates from Plastics to Elastomers via Stereoselective Copolymerizations of rac-β-Butyrolactone and β-Propiolactone

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Chinese Journal of Chemistry 2024年第9期42卷 963-972页

作者： Haoran Zhang JiaojiaoQin xiaoyan Tang Beijing National Laboratoryfor Molecular Sciences Key Laboratory of Polymer Chemistry and Physics of Ministry of EducationCenterfor Soft Matter Science and EngineeringCollegeof Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Poly(3-hydroxybutyrate),a crucial member of the large biodegradable polyhydroxyalkanoate family,suffers from its *** enhance its performance,we employed a straightforward approach involving the ring-opening copolymerization of racemic-β-butyrolactone(rac-β-BL)andβ-propiolactone(β-PL)using the syndio-selective amino-alkoxy-bis(phenolate)-yttrium complex as a catalyst,thanks to the excellent ductility of poly(3-hydroxypropionate).Control over the rac-β-BL/β-PL feeding ratios and polymerization time yielded random or block copolymers with tunable thermal and mechanical properties comparable to traditional fossil-based ***,we achieved one-pot synthesis of hard-soft-hard triblock copolymers by exploiting monomers’different copolymerization rates and a bifunctional initiator,thus transforming polyhydroxyalkanoates from hard and tough plastics to soft and ductile thermoplastic elastomers.

关键词： Ring-opening(co-)polymerization Biodegradable polymers Polyhydroxyalkanoates Copolymers Plastics Elastomers

Characteristics of bioaerosols under high-ozone periods,haze episodes,dust storms,and normal days in Xi'an,China

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Particuology 2024年第7期90卷 140-148页

作者： Yiming Yang Liu Yang xiaoyan Hu Zhenxing Shen Department of Environmental Science and Engineering Xi’an Jiaotong UniversityXi’an710049China Key Lab of Aerosol Chemistry&Physics SKLLQGInstitute of Earth EnvironmentChinese Academy of SciencesXi’an710049China

The characteristics of bioaerosols and their effects on human beings'health have become a major public concern in the recent *** study compared the characteristics of bioaerosols under different types of pollution(high-ozone[HO]episodes,haze episodes,and dust storms[DSs]),with those of bioaerosols on normal days(NDs)in Xi'an,*** concentrations,diurnal variations,and size distribution of bacteria,fungi,and total airborne microbes(TAMs)were *** results showed that the bacterial and fungal concentrations were the highest during DSs and on NDs,reaching 425.2 and 956.9 colony-forming units/m^(3),*** concentration of TAMs was the highest during HO episodes,reaching 10.7×10^(6)cells/m^(3),which was significantly higher than that during the other *** maximum concentrations of bacteria and fungi during HO episodes were observed in the morning,while they appeared separately in the morning and evening during haze *** and TAMs during DSs reached peak concentrations in the morning and evening,which is opposite to the particulate matter(PM)distribution *** NDs,temperature and relative humidity had significant effects on *** size distributions of airborne bacteria exhibited bimodal patterns,whereas unimodal distributions were observed for *** mainly attached in fine particles(<2.1μm)with proportions of 67.4%and 60.5%during haze episodes and DSs,respectively,which means that fungi were easily penetrated into the human respiratory *** evaluation of influence factors revealed that PM_(2.5) and PM10 had negative effects on fungal concentration during DSs,and ozone concentration and temperature were inversely correlated with fungal concentration during HO *** results provide valuable reference data for elucidating the formation and evolution of bioaerosols under different types of pollution.

关键词： Bacteria Fungi Total airborne microbe Different air pollution types Influence factors

Design optimization of a hexapod vibration isolation system for electro-optical payload

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Chinese Journal of Aeronautics 2024年第2期37卷 330-342页

作者： Jing LI Weipeng LI xiaoyan ZHANG Hai HUANG School of Astronautics Beihang UniversityBeijing 100191China

The electro-optical payloads on mobile platforms generally suffer undesirable vibrations generated by maneuvers and *** vibrations are in six degrees of freedom and cause line-of-sight jitters,resulting in image blurring and loss of tracking *** this paper,a Hexapod Vibration Isolation System(HVIS)is proposed and optimized to solve this *** optimization aims to centralize and minimize the natural frequencies of HVIS,for expanding the vibration isolation bandwidth and improving the vibration isolation in the higher frequency *** that the design space for HVIS is limited and interfered with the frames of the mobile platform,a non-collision algorithm is proposed and applied in the optimization to obtain the feasible optimal *** optimization result shows that the natural frequency bandwidth has been reduced by 42.9%,and the maximum natural frequency is reduced by 30.2%.The prototypes of initial and optimal designs are manufactured and *** simulated and experimental results demonstrate the validity of the optimization,and the optimal design provides a maximum of 15 dB more isolation in rotation direction than the initial design.

关键词： Electro-optical payload Vibrations Isolation system Hexapod Optimization Non-collision design

Photodegradation of xylene isomers:Kinetics,mechanism,secondary pollutant formation potential and health risk evaluation

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Journal of Environmental Sciences 2024年第2期136卷 658-669页

作者： xiaoyan Chen Weikun Zhu Sufen Feng Jiangyao Chen Guangdong Key Laboratory of Environmental Catalysis and Health Risk Control Guangdong Technology Research Center for Photocatalytic Technology Integration and Equipment EngineeringInstitute of Environmental Health and Pollution ControlGuangdong University of TechnologyGuangzhou 510006China Guangzhou Key Laboratory of Environmental Catalysis and Pollution Control Guangdong-Hong Kong-Macao Joint Laboratory for Contaminants Exposure and HealthSchool of Environmental Science and EngineeringGuangdong University of TechnologyGuangzhou 510006China

Photodegradation technology has been widely applied in the purification of industrial aromatic ***,whether this technology efficiently removes the pollutants to prevent secondary pollution and health risk is still ***,the photodegradation processes of three xylenes were compared under designed reaction atmospheres and light *** lamp showed poor photodegradation ability toward xylenes,no matter in N_(2) or N_(2)+O_(2)system,while much higher photodegradation performance of xylenes were obtained under ultraviolet(UV)and vacuum ultraviolet(VUV)irradiation,especially in N_(2)+O_(2)+VUV system,where 97.9%of m-xylene,99.0%of o-xylene or 87.5%of p-xylene with the initial concentration of 860 mg/m^(3) was removed within 240 *** xylenes underwent three processes of photo-isomerization,photodecomposition and photo-oxidation to produce intermediates of aromatics,alkanes and *** them,the photo-isomerization products showed the highest concentration percentage(e.g.,≥50%in o-xylene system),confirming that photo-isomerization reaction was the dominated photodegradation process of ***,these isomerized products not only contributed about 97%and91%to the formation potential of O3(OFP)and secondary organic aerosols(SOAFP),but also displayed obvious non-carcinogenic risk,although one of photodecomposition product—benzene showed the highest occupational exposure ***,the secondary pollution and health risks of photodegradation products of xylenes were non-ignorable,although the OFP,SOAFP and health risks of the generated products reduced at least 4.5 times in comparison with that of the degraded *** findings are helpful for the appropriate application of this technology in the purification of industrial organic waste gas.

关键词： Isomer aromatics Photodegradation Ozone formation Secondary organic aerosols Health risk