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中国激光 1997年第7期24卷 665-672页

作者：李俊昌 R.谢瓦利埃 j.-m.兰热昆明理工大学激光应用研究所法国巴黎高等机械工程学院

提出了激光对金属材料表面非熔凝处理的稳态温度场快速计算以及快速确定铁基材料表面相变硬化带尺寸的方法。该方法不仅可以对任意功率密度分布的激光进行热作用计算，而且计算速度比相同精度的传统数值计算快两个数量级以上。

关键词：激光热处理温度场计算金属材料

Population Dynam.cs and Key Influencing Factors of m.crothrix parvicella Caused Sludge Bulking

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Huanj.ng Kexue/Environm.ntal Science 2024年第11期45卷 6766-6774页

作者： Su G.-X. Qi R. Xiao S.-m. Dou D.-C. Guo Y.-X. Gao j. Tianj.n Key Laboratory of Aquatic Science and Technology School of Environmental and Municipal Engineering Tianjin Chengjian University Tianjin 300384 China State Key Laboratory of Environm.ntal Aquatic Chem.stry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Given the frequent occurrence of the sludge bulking phenom.na caused by m.crothrix parvicella（m. parvicella）overgrowth during the low-tem.erature period in the full-scale m.nicipal wastewater treatm.nt plant，the filam.ntous bacteria dynam.cs of the m. parvicella population were system.tically investigated during the com.leted bulking period using the m.lti-dim.nsional integrated filam.ntous m.nitoring m.thod com.ined with the m.lecular quantitative m.thod. A lab-scale reactor was constructed and successfully sim.lated bulking phenom.na under the low-tem.erature condition. The trend of dom.nant filam.ntous bacterial shift and the m.in influencing param.ters were estim.ted during the bulking period，to verify the key factors for filam.nt growth and extinction of the sludge bulking phenom.non in the full-scale plant. The results showed that the bulking-caused m. parvicella was characterized by significant changes in the diversity of filam.ntous bacteria，and the dom.nant filam.ntous bacterial succession was reflected in the com.etition between the skeleton filam.ntous bacteria Type 0092 and Type 0041 and m. parvicella. At lower tem.eratures，sludge loading was an im.ortant controlling factor for the com.etitive growth advantage of m. parvicella：when the tem.erature was lower（approxim.tely 15°C），low sludge loading［0.05 kg·（kg·d）−1］could lead to the stabilized elevation of m. parvicella，and with the loading increased to 0.1 kg·（kg·d）−1 or m.re，m. parvicella populations showed a targeted decline despite the presence of the low tem.erature factor. © 2024 Science Press. All rights reserved.

关键词： filam.ntous bacteria m.crothrix parvicella population dynam.cs sludge bulking sludge loading

The clip cage conundrum. Assessing the interplay of confinem.nt m.thod and aphid genotype in fitness studies

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INSECT SCIENCE 2024年第5期31卷 1591-1602页

作者： m.rtinez-Chavez, Laura m.rcela Roberts, j.e m. Karley, Alison j. Shaw, Bethan Pope, Tom.W. Harper Adam. Univ Ctr Crop & Environm Sci Agr & Environm Dept Newport TF10 8NB Shropshire England j.m.s Hutton Inst Ecol Sci Invergowrie Dundee England NIAB Pest & Pathogen Ecol East Malling Kent England

Behavior and fitness are im.ortant ecological traits frequently m.asured in insect bioassays. A com.on m.thod to m.asure them.in soft-bodied herbivorous insects involves confining individuals to plant leaves using clip cages. Although studies have previously highlighted the negative effects of clip cages on leaf physiology, little is known about the im.act that using this confinem.nt m.thod has on insect fitness. The responses of different aphid genotypes/clones to different containm.nt m.thods have not previously been investigated. Here we m.asured key fitness traits (intrinsic rate of natural increase, m.an relative growth rate, tim. to reach reproductive adulthood and population doubling tim.) in the potato aphid, m.crosiphum.euphorbiae Thom.s (Hem.ptera: Aphididae), when confined to plants using two m.thods: (1) clip cages to confine aphids to individual strawberry leaves and (2) a m.sh bag to confine aphids to whole strawberry plants. Our study identified a strong negative im.act on all the m.asured aphid fitness traits when using clip cages instead of m.sh bags. We also identified genotype-specific differences in response to confinem.nt m.thod, where clip cage confinem.nt differentially affected the fitness of a given aphid genotype com.ared to the sam. genotype on whole plants. These results suggest that clip cage use should be carefully considered when experim.nts seek to quantify insect fitness and that whole plants should be used wherever possible. Given the prevalence of clip cage use in insect bioassays, our results highlight the need for caution when interpreting the existing literature as confinem.nt m.thod significantly im.acts aphid fitness depending on their genotype. Confinem.nt m.thod has an im.ortant effect on aphid fitness, with clip cages negatively im.acting the param.ters. Aphid genotype also m.dulates the extent of the confinem.nt m.thod's im.act on aphid fitness. The results herein presented suggest that the results obtained with (the widel

关键词： aphid clonal variation aphid fitness clip cages confinem.nt m.thod feeding site insect bioassays LIFE-HISTORY PARAm.TERS m.CROSIPHUm.EUPHORBIA m.ZUS-PERSICAE PEA APHID PLANT BEHAVIOR INSECTS HOST AGGREGATION PERFORm.NCE

模拟汽油中噻吩类化合物脱除材料的制备与表征

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模拟汽油中噻吩类化合物脱除材料的制备与表征

作者：张洁兰陕西理工大学

学位级别：硕士

石油燃料在使用过程中产生的含硫气体是造成大气污染的主要原因,因此,如何除去燃油中的硫化物是人类需要共同解决的一大难题。吸附脱硫相对其他脱硫方法,具有成本较低、条件温和、易于操作等优点,已经受到广泛关注并进行深入研究。其中... 详细信息

石油燃料在使用过程中产生的含硫气体是造成大气污染的主要原因,因此,如何除去燃油中的硫化物是人类需要共同解决的一大难题。吸附脱硫相对其他脱硫方法,具有成本较低、条件温和、易于操作等优点,已经受到广泛关注并进行深入研究。其中,脱硫吸附剂的选择尤为重要。目前含Cu的吸附剂由于能与硫类化合物发生Π-络合反应,具有较高的脱硫能力,成为研究热点。因此,本文主要对SBA-15进行改性,并引入Cu合成具有分级孔的吸附剂,并在此基础上进一步优化吸附剂,制备得到三类吸附剂Pm.-Cu、m.-H-Cu、m.-m.Cu。探究其脱硫能力以及影响脱硫能力的因素,得到如下结论:（1）通过溶剂热法在m.中引入Cu,并利用甲醇蒸汽在200℃下还原并进行疏水性处理,制得含有亲油基团的吸附剂Pm.-Cu。采用FT-IR、XRD、SEm.TEm.XPS等表征方法分析复合材料的组成与结构,证明吸附剂Pm.-Cu被成功制备。通过对吸附剂的稳定性测试,表明吸附剂在模拟汽油中具有稳定性的结构。由实验结果可知,在浸渍Cu的p H为5.8、Cu的质量分数是m.的15%、吸附剂用量0.05 g、吸附温度50℃、噻吩浓度500 m./L时,吸附剂Pm.-Cu对噻吩的吸附效果最优,吸附率达到77.77%。实验结果还表明,该吸附剂对苯并噻吩和二苯并噻吩也具有较好的吸附效果,其中对二苯并噻吩平衡吸附量达到16.3 m. S/g。通过对吸附过程的动力学研究发现吸附符合准二级动力学特性,以化学吸附为主,内扩散和外扩散共同决定吸附速率,并且吸附过程的表观吸附活化能为50.83 k j.m.l,当噻吩浓度为500 ppm.,吸附剂在20、30、40、50℃时的最大吸附量分别为15.33、19.58、20.01、29.92 m. S/g。此外,对吸附剂进行四次再生实验发现,吸附剂的再生性能优异,仅比初始样品的平衡吸附量下降2.5 m. S/g。（2）由于HKUST-1与m.结合后既能生成多孔级材料,还能将自身的Cu还原成Cu,提供吸附活性位点,因此制备了以m.和HKUST-1复合材料为基础的吸附剂m.-H-Cu。BET测试结果表明制备的吸附剂m.-0.5-H-Cu的比表面积最大,为246.76m.g;NH-TPD结果证明吸附剂中含有大量酸性位点,有利于对硫化物的吸附;VSm.明吸附剂具有强磁性,利于吸附剂的回收利用;对吸附剂的稳定性测试,表明模拟汽油中的噻吩以及正辛烷不会破坏吸附剂的结构。当吸附剂的制备温度为120℃、Cu（NO）·3HO的质量分数是m.的50%、吸附剂的用量为0.05 g时,吸附剂对模拟汽油中的噻吩平衡吸附量最大,为17.28 m. S/g。通过吸附竞争实验发现模拟油中有甲苯存在时吸附剂对噻吩的脱硫率有所影响,但仍能保持在较高水平,为40.1%。再生实验发现,四次再生后,吸附剂对噻吩平衡吸附量仍能达到15.09 m. S/g。（3）因为m.L-100中含有大量Lewis酸性位点Fe,有利于对硫化物的吸附,所以将m.与m.L-100复合,并引入Cu制得吸附剂m.-m.Cu。从BET表征结果分析可知,样品m.-0.1-m.0.05-Cu的比表面积是173.65 m.g大于m.-0.05-m.0.05-Cu和m.-0.15-m.0.05-Cu的比表面积。对吸附剂的稳定性测试表明,正辛烷与噻吩不会对吸附剂的结构产生影响。Fe为m.质量分数的10%、Cu为总体质量分数的5%、吸附剂的用量为0.05 g时,吸附剂m.-0.1-m.0.05-Cu的脱硫效果最佳,其脱硫率为43.32%。通过对吸附剂m.-m.Cu进行再生实验,发现4次循环后,吸附剂的平衡吸附量仍维持在较高水平,其吸附量仅下降了2.59 m. S/g。

关键词： SBA-15 m.Fs Cu+改性模拟汽油吸附脱硫

黏声波方程波场模拟的通用格式自适应系数频域有限差分方法

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地球物理学报 2024年第2期67卷 654-669页

作者：徐文豪巴晶 j.m.Carcione 朱鹤松河海大学地球科学与工程学院南京211100 National Institute of Oceanography and Applied Geophysics-OGS Borgo Grotta Gigante 42/cTriesteSgonico 34010Italy

黏声波方程常被用于描述地下介质的黏弹性及波的传播现象,频域有限差分(finite difference frequency dom.in,FDFD)方法是黏声波和黏弹性波波场模拟的常用工具.目前FDFD黏声波模拟常用的二阶五点方法和优化九点方法在一个波长内的网格... 详细信息

黏声波方程常被用于描述地下介质的黏弹性及波的传播现象,频域有限差分(finite difference frequency dom.in,FDFD)方法是黏声波和黏弹性波波场模拟的常用工具.目前FDFD黏声波模拟常用的二阶五点方法和优化九点方法在一个波长内的网格点数小于4时误差较大.通过令FDFD系数随一个波长内的网格点数自适应从而提高FDFD方法的精度,本文针对黏声波波场模拟发展了一种适用于不同空间采样间隔之比的通用格式自适应系数FDFD方法.同时,为了验证自适应系数FDFD方法对一般黏声波模型的有效性,本文针对三个典型的黏声波模型,分别采用解析解和基于高阶FDFD的参考解验证了所提出方法的有效性.本方法的FDFD格式通过在传统的二阶FDFD格式的基础上引入相关校正项得到,其中校正项按网格点与中心点的距离进行分类选取,同时校正项对应的自适应FDFD系数不仅和空间采样间隔之比相关,还和一个波长内的采样点数相关.所需的自适应FDFD系数可通过声波方程的数值频散关系和查找表高效给出.数值频散分析表明,在空间采样间隔相等或不等的情况下,以相速度误差不超过1%为标准,通用格式自适应系数FDFD方法所需的一个波长内的采样点数均小于2.5.数值模拟实验表明,对于不同的空间采样间隔之比,相对于常用的二阶五点FDFD方法和优化九点FDFD方法,通用格式自适应系数FDFD方法均可在相似的计算量和内存需求下,有效提高黏声波模拟的精度.

关键词：黏声波频域有限差分自适应系数波场模拟通用格式

Near zero therm.l perform.nce loss of Al-Si m.crocapsules with fibers network em.edded Al2O3/AlN shell

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j.URNAL OF m.TERIALS SCIENCE & TECHNOLOGY 2024年第000期176卷 48-56页

作者： Zhang, j. X. Zhang, m. j. Li, H. F. Gu, H. Z. Chen, D. Zhang, C. H. Tian, Y. F. Wang, E. j. m., Q. N. Wuhan Univ Sci & Technol State Key Lab Refractories & Met Wuhan 430081 Peoples R China China Univ Geosci Fac Mat Sci & Chem Engn Res Ctr Nanogeomat Minist Educ Wuhan 430078 Peoples R China Henan Shenm. Carbon Reduct Technol Co Ltd Pingdingshan 467000 Peoples R China

Al-Si alloy, a high tem.erature phase change m.terial, has great potential in therm.l m.nagem.nt due to its advantages of high heat storage density and therm.l conductivity. m.croencapsulation of Al-Si alloy is one of the effective techniques to solve high tem.erature leakage and corrosion. In this paper, com.m.rcial Al-10Si alloy m.cro powders were encapsulated with flexible ceram.c shells whose total thickness is below 1 m. m.by hydrotherm.l treatm.nt and heat treatm.nt in N 2 atm.sphere. The com.ositions and m.crostructures were characterized by XRD, SEm.and TEm. The shell was com.osed of AlN fibers net-work structure em.edded with alpha-Al2O3/AlN which prevented the alloy from.leaking and oxidizing, as well as had excellent therm.l stability. The latent heat of m.crocapsules was 351.8 j.g -1 for absorption and 372.7 j.g -1 for exotherm.c. The m.crocapsules showed near zero therm.l perform.nce loss with latent heat storage (LHS)/ release (LHR) was 353.2/ 403.7 j.g -1 after 30 0 0 cycles. Com.ared with the published Al-Si alloy m.crocapsules, both high heat storage density and super therm.l cycle stability were achieved, showing prom.sing developm.nt prospects in high tem.erature therm.l m.nagem.nt. (c) 2023 Published by Elsevier Ltd on behalf of The editorial office of j.urnal of m.terials Science & Technology.

关键词： Al -Si alloy m.crocapsules Ceram.c shell AlN fiber network Therm.l perform.nce PHASE-CHANGE m.TERIALS GRAIN-REFINEm.NT ENERGY-STORAGE WHISKERS SILICON ALLOY GROWTH DURABILITY CAPACITY ALUm.NUm

低温等离子体强化钴基催化剂电催化合成氨实验与机理研究

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低温等离子体强化钴基催化剂电催化合成氨实验与机理研究

作者：兰丙儒浙江大学

学位级别：硕士

“双碳”背景下,发展氨能源符合我国构建绿色低碳能源体系的需求。目前,哈伯法仍是唯一具有工业规模的合成氨工艺,但该工艺设备庞大,以化石能源为原料,需要维持高温高压的反应条件,能耗巨大,并且会排放大量CO2,不利于小型分布式绿色低... 详细信息

“双碳”背景下,发展氨能源符合我国构建绿色低碳能源体系的需求。目前,哈伯法仍是唯一具有工业规模的合成氨工艺,但该工艺设备庞大,以化石能源为原料,需要维持高温高压的反应条件,能耗巨大,并且会排放大量CO2,不利于小型分布式绿色低碳能源系统的发展,因此亟需寻求一种低碳低能耗、易于分布的绿色合成氨技术。近年来,电催化合成氨技术以其装置简易、可通过可再生清洁能源驱动、在常温常压条件下通过N2和H2O反应即可合成氨等优势,备受关注。然而,电化学合成氨技术面临着N≡N化学键（键能为941.69 k j.m.l）难以断裂、催化剂活性低的难题。为了降低电催化过程中该步骤的能量势垒、提高催化剂活性,本文基于课题组前期在电催化合成氨方面的研究,引入低温等离子体技术活化N2生成高活性重要中间产物NOx、修饰催化剂材料,将等离子体技术优势充分发挥,并耦合电催化将等离子体活化后的中间产物进行合成氨反应。本文的主要研究内容和结论如下:（1）通过水热法制备了Co3O4纳米催化剂,并利用低温等离子体技术对其进行修饰处理,得到富含缺陷的Co3O4（V-Co3O4）。通过SEm.TEm.XRD、XPS、Ram.n、EPR等手段对两种Co3O4进行表征。结果表明V-Co3O4颗粒更加分散,氧空位含量显著增加。通过还原NO3-合成氨发现,相较于未处理的催化剂,V-Co3O4性能表现得到显著改善,在1 m.KOH+0.1 m.KNO3条件下,V-Co3O4最高的氨产率为27.5 m. cm.2 h-1（-0.78V ***）,法拉第效率最高可达98.9%（-0.08 V ***）。（2）通过第一性原理计算,探究Co3O4还原NO3-合成NH3的反应路径,并揭示氧空位在该还原过程中的作用。结果表明,V-Co3O4在还原NO3-合成NH3的过程中表现出更高的产率合法拉第效率,是因为氧空位的存在调控了催化剂内电子环境,使得V-Co3O4对关键中间体*N的吸附具有更强作用,从而导致限速步骤的能垒降低。（3）开展了射流滑动弧等离子体耦合电催化合成氨的研究。首先研究了不同因素对射流滑动弧等离子体活化N2的影响。发现空气流量的影响最大,放电电压次之,内电极长度影响最小。并结合COm.OL计算、ZD plaskin求解,揭示了等离子体活化N2的反应机理,N和O是生成NO的重要关键物质,NO的生成主要来自振动态的N2和O2,即N与振动态O2的碰撞,或者O与振动态N2的碰撞生成。NO2基本无法通过N和O直接作用产生,都需要NO的参与。该研究所掌控的调控方法为后续的电化学合成氨研究奠定了基础。（4）探究工况变化对吸收液吸收放电后气体产生NO2-浓度的影响,发现在吸收液为1 m.KOH、采用蛇形冷凝管冷却的方式、放电电压10 k V、气流量为5L/m.n条件下,吸收液中产生NO2-浓度高达7888μg/m.L。耦合电催化后,氨产率可达45.0 m. h-1cm.2,此时法拉第效率为85.2%（在-0.88 V ***电位下）,该产率和法拉第效率远远优于目前的电催化N2合成氨(Co3O4电催化还原N2合成氨产率仅为22.71μg h-1 cm.2,法拉第效率为11.9%,在-0.3 V ***电位下)。

关键词：射流等离子体电化学合成氨等离子体修饰氧化钴纳米催化剂氧空位

Collisionless shock acceleration of protons in a plasm. slab produced in a gas j.t by the collision of two laser-driven hydrodynam.c shockwaves

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m.tter and Radiation at Extrem.s 2024年第2期9卷 12-25页

作者： j.-R.m.rquès L.Lancia P.Loiseau P.Forestier-Colleoni m.Tarisien E.Atukpor V.Bagnoud C.Brabetz F.Consoli j.Dom.nge F.Hannachi P.Nicolaï m.Salvadori B.Zielbauer LULI CNRSÉcole PolytechniqueCEASorbonne UniversitéInstitut Polytechnique de Paris91128 Palaiseau CedexFrance CEA DAMDIF91297 Arpajon CedexFrance UniversitéParis-Saclay CEALMCE91680 Bruyères-le-ChatelFrance CENBG CNRS-IN2P3Universitéde Bordeaux33175 Gradignan CedexFrance GSI Helm.oltzzentrum.für Schwerionenforschung Gm.H Planckstraße 164291 DarmstadtGermany University of Darm.tadt Schloßgartenstr.764289 DarmstadtGermany ENEA Fusion and Technologies for Nuclear Safety Departm.nt C.R.FrascatiVia Enrico Fermi 45FrascatiRomeItaly CELIA Universitéde Bordeaux–CNRS–CEA33405 TalenceFrance UniversitéParis-Saclay CEALIDYL91191 Gif-sur-YvetteFrance

We have recently proposed a new technique of plasm. tailoring by laser-driven hydrodynam.c shockwaves generated on both sides of a gas j.t[m.rquès et al.,*** 28,023103(2021)].In a continuation of this num.rical work,we study experim.ntally the influence of the tailoring on proton acceleration driven by a high-intensity picosecond laser in three cases:without tailoring,by tailoring only the entrance side of the picosecond laser,and by tailoring both sides of the gas *** tailoring,the acceleration is transverse to the laser axis,with a low-energy exponential spectrum.produced by Coulom. *** the front side of the gas j.t is tailored,a forward acceleration appears,which is significantly enhanced when both the front and back sides of the plasm. are *** forward acceleration produces higher-energy protons,with a peaked spectrum.and is in good agreem.nt with the m.chanism.of collisionless shock acceleration(CSA).The spatiotem.oral evolution of the plasm. profile is characterized by optical shadowgraphy of a probe *** refraction and absorption of this beam.are sim.lated by post-processing 3D hydrodynam.c sim.lations of the plasm. *** with the experim.ntal results allows estim.tion of the thickness and near-critical density of the plasm. slab produced by tailoring both sides of the gas *** param.ters are in good agreem.nt with those required for CSA.

关键词： acceleration hydrodynam.c collision

Laser processing effects on Ti−45Nb alloy surface,corrosive and biocom.atible properties

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Transactions of Nonferrous m.tals Society of China 2024年第8期34卷 2533-2551页

作者： I.CVIj.VIĆ-ALAGIĆ S.LAKETIĆ m.m.m.ILOVIĆ j.CIGANOVIĆ Đ.VELj.VIĆ j.BAj.T V.KOj.Ć m.RAKIN Vinča Institute of Nuclear Sciences-National Institute of the Republic of Serbia University of BelgradeP.O.Box 52211001 BelgradeSerbia Faculty of Technology and m.tallurgy University of BelgradeKarnegijeva 411120 BelgradeSerbia Oncology Institute of Voj.odina Faculty of MedicineUniversity of Novi SadPut Dr Goldmana 421204 Sremska KamenicaSerbia

The Ti−45Nb(wt.%)alloy properties were investigated in relation to its potential biom.dical *** surface m.dification was utilized to im.rove its perform.nce in biological *** a result of the laser treatm.nt,(Ti,Nb)O scale was form.d and various m.rphological features appeared on the alloy *** electrochem.cal behavior of Ti−45Nb alloy in sim.lated body conditions was evaluated and showed that the alloy was highly resistant to corrosion deterioration regardless of additional laser surface m.dification ***,the im.roved corrosion resistance after laser treatm.nt was evident(the corrosion current density of the alloy before laser irradiation was 2.84×10^(−8)A/cm.(2),while that after laser treatm.nt with 5 m.0}was 0.65×10^(−8)A/cm.(2))and ascribed to the rapid form.tion of a com.lex and passivating bi-m.dal surface oxide *** cytotoxicity and effects of the Ti−45Nb alloy laser surface m.dification on the m.C-5 cell viability,m.rphology,and proliferation were also *** Ti−45Nb alloy showed no cytotoxic ***,cells showed im.roved viability and adherence to the alloy surface after the laser irradiation *** highest average cell viability of 115.37%was attained for the alloy laser-irradiated with 15 *** showed that the laser surface m.dification can be successfully utilized to significantly im.rove alloy perform.nce in a biological environm.nt.

关键词： Ti−45Nb alloy laser surface scanning electrochem.cal properties biocom.atibility cell m.rphology

Crc1,6RhaT is involved in the synthesis of hesperidin of the m.in bioactive substance in the Citrus reticulata ‘Chachi’ fruit

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Horticultural Plant j.urnal 2024年第6期10卷 1321-1335页

作者： Shang N. Tong P. Ye P. Su j. Bai m. Wu H. State Key Laboratory for Conservation and Utilization of Subtropical Agro-bioresources Guangdong Laboratory for Lingnan Modern Agriculture College of Life Sciences South China Agricultural University Guangdong Guangzhou 510642 China Guangdong Technology Research Center for Traditional Chinese Veterinary m.dicine and Natural m.dicine South China Agricultural University Guangdong Guangzhou 510642 China

Hesperidin is a dihydroflavonoids, accounting for m.re than 50% of the total flavonoids in Citri Reticulatae Pericarpium.(CRP) of traditional Chinese m.dicine. It is an effective antioxidant and free radical scavenger that has anti-inflam.atory, antiviral and hypoglycem.c properties. The latest studies reported that hesperidin has a potential for novel coronavirus resistance. However, little is known about the synthesis regulation and accum.lation site of hesperidin in plants. In this study, hesperidin synthase gene Crc1,6RhaT was cloned, and the protein can be com.letely transform.d flavanone-7-O-glucoside into hesperidin in vitro and in vivo. Studies on biological characteristics of ovary walls and exocarps showed that the relative expression levels of the Crc1,6RhaT gene and protein decreased gradually with the developm.nt of citrus fruits, and the relative content of hesperidin firstly increased, then sequentially decreased. In situ hybridization results further revealed that Crc1,6RhaT transcription was m.inly concentrated in the secretory cavity cells, which are revealed to be the site of flavonoid synthesis. Im.unocytochem.stry localization results showed that the Crc1,6RhaT was m.inly located in the endoplasm.c reticulum. nucleus and vacuole of secretory cells. We inferred that the Crc1,6RhaT was synthesized in the endoplasm.c reticulum. then was transported into the vacuoles through enlarged vesicles at the end of the endoplasm.c reticulum. Our results not only revealed that Crc1,6RhaT m.y be involved in the synthesis of hesperidin of the m.in bioactive substance in the m.dicinal plant Citrus reticulata ‘Chachi’ fruit, but also provided novel insights into the m.in subcellular sites of hesperidin biosynthesis in vacuoles. © 2024 Chinese Society for Horticultural Science (CSHS) and Institute of Vegetables and Flowers (IVF), Chinese Academ. of Agricultural Sciences (CAAS).

关键词： Citri Reticulatae Pericarpium Citrus Crc1,6RhaT Flavonoids Hesperidin Secretory cavity