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comprehensive evaluation of Korla fragrant pears and optimization of plucking time during the harvest period

International Journal of Agricultural and Biological Engineering 2022年第3期15卷 242-250页

作者： Zhentao Wang Yurong Tang xiaozhen Jin Yang Liu Hong Zhang Hao Niu Haipeng Lan college of Mechanical and Electrical Engineering Tarim UniversityAlar 843300XinjiangChina Zibo Agricultural Machinery Service center Zibo 255000ShandongChina

To optimize the harvest of Korla fragrant pears and to provide a theoretical basis for post-harvest processing,a total of 26 basic indices of Korla fragrant pears,including their morphology,quality,and softening age,were *** harvest period ranged from August 22nd to October 6th,samples were collected every 5 d(totally 10 plucking days,indicated as H1-H10).The results indicated that changes in pectin content were the main causes of softening in fragrant *** scavenging of free radicals mainly occurred because of the collaborative effects of superoxide dismutase(SOD)and catalase(cAT).In the harvest periods H1-H3,the hardness,titratable acid(TA),chlorophyll content,density,and diameter of the stone cells,as well as the cellulose and hemicellulose content of the Korla fragrant pears were at their *** the periods H7-H10,the single-fruit weight,fruit horizontal and vertical diameter,color coordinates L,a*,b*,soluble-solids content(SSc),SOD activity,cAT activity,and water-soluble pectin were higher than in the other plucking *** highest vitamin c(Vc)content and moderate values for a variety of indicators were observed during *** in the Korla fragrant pears during H1-H3 mainly manifested through changes in softening-related *** H3-H10,changes in the softening-related,aging-related,color-related,and quality indices had a dominant *** this basis,some suggestions for the post-harvest processing of fragrant pears have been ***,during H1-H3,are suitable for transportation and storage;during H7-H10 are suitable for fresh-eating and further processing;and during H3-H7,exhibited moderate values for a variety of indicators and had the highest commercial *** research provides a systematic evaluation of the characteristics of mature Korla fragrant pears during the harvest period and can form the basis for fruit quality control and processing of Korla fragrant pears.

关键词： Korla fragrant pear harvest period plucking time quality fruit maturity evaluation optimization

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Geochemical,mineralogical,and petrological characteristics of the cretaceous coal from the middle Benue Trough Basin,Nigeria:Implication for coal depositional environments

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Energy Geoscience 2022年第3期3卷 300-313页

作者： Segun A.Akinyemi James c.Hower Henry Y.Madukwe Bemgba B.Nyakuma Mohammed B.Nasirudeen Timileyin A.Olanipekun Rabelani Mudzielwana Mugera W.Gitari Luis F.O.Silva Department of Geology Faculty of ScienceEkiti State UniversityP.M.B 5363Ado EkitiEkiti StateNigeria Energy Environmental and Nanosciences GroupDepartment of GeologyEkiti State UniversityP.M.B 5363Ado-EkitiEkiti StateNigeria University of Kentucky Centre for Applied Energy Research2540 ResearchPark DriveLexingtonKY40511USA Department of Earth&Environmental Sciences University of KentuckyLexingtonKY40506USA Department of chemistry Faculty of SciencesBenue State UniversityP.M.B.102119MakurdiBenue StateNigeria Department of chemistry Faculty of ScienceFederal University of LafiaP.M.B.146LafiaNasarawa StateNigeria Institute of Earth and Environmental Sciences Albert Ludwigs Universitat FreiburgAlbert Straße 23-B79104Freiburg Breisgau Germany Department of Ecology and Resources Management University of VendaPrivate BagX5050Thohoyandou0950LimpopoSouth Africa Department of civil and Environmental Universidad de la CostaCalle 58#55-66080002BarranquillaAtlanticoColombia

The Benue Trough Basin (BTB) of Nigeria is geologically and geo-morphologically subdivided into upper,middle, and lower segments. The BTB is the subject of geological research due to its rich coal depositsthat have the potential for oil and gas. The purpose of the present study is to examine the origins,depositional environments, and thermal history of the selected coals and the processes that influencetheir quality. coal samples from different open cast coal mines in the middle BTB were examined usingproximate and ultimate, x-ray diffraction (xRD), x-ray fluorescence (xRF), laser ablation induced coupledplasma (LA-IcPMS), and petrographical analyses. The coal samples contained mainly quartz, kaolinite,and organic carbon. The xRD spectra peaks revealed the triclinic and monoclinic structure of kaolin. TheSiO2/Al2O3 ratios confirmed the dominance of quartz and kaolinite. The Ni/co versus V/cr, cu/Zn, and V/Mo values in the studied coals suggest oxic depositional environments, whereas the V/(Ni þ V) and V/(V þ cr) values indicate oxic to suboxic conditions. The ce/ce* values are slightly below 1, which indicates a suboxic depositional environment. Maceral texture is indicative of transformations from subbituminous to high volatile c or B bituminous coal. The maceral components and mineral matter(10%) of the studied coals imply deposition in the planar margin mire, and a river system of planarmargin mire environments, respectively. The high gelification index (GI) and tissue preservation index(TPI) values indicate peat accumulation developed within a wet forest swamp. The ternary diagram ofthe maceral component suggests deposition in a wet moor environment with intermittent moderate tohigh flooding episodes. The studied coals are sub-hydrous vitrinite inferring hydrogen-poor and thermally immature characteristics. The low V and Ni contents, low H/c and high O/c, indicate Type IIIterrestrial organic matter with the potential to generate gaseous hydrocarbons. The investi

关键词： coal Maceral Trace elements Mineralogy Depositional environments

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Improving bermudagrass in the Southeastern United States with alfalfa as an alternative nitrogen source in grazing systems

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Grassland Research 2022年第4期1卷 280-289页

作者： Justin c.Burt Lisa L.Baxter christopher G.Prevatt Mary Kimberly Mullenix R.Lawton Stewart Jr. Jennifer J.Tucker Department of Animal and Dairy Science University of GeorgiaTiftonGeorgiaUSA Department of crop and Soil Science University of GeorgiaTiftonGeorgiaUSA Regional Specialized Agent Range Cattle RECUniversity of FloridaGainesvilleFloridaUSA Department of Animal Science Auburn UniversityAuburnAuburnUSA Department of Animal and Dairy Science University of GeorgiaAthensGeorgiaUSA

Background Bermudagrass(cynodon spp.)is one of the most common perennial warm-season forages grown in the Southeastern United *** incorporation of alfalfa(Medicago sativa)into bermudagrass pastures could serve as an alternative source of nitrogen(N)while also improving the nutritive value of the forage *** A 2-year grazing evaluation arranged in a randomized complete block design was conducted from May to September 2018(Year 1)and May–August 2019(Year 2)in Tifton,GA,*** objective was to compare the production of alfalfa–bermudagrass mixed pastures(BGA)with bermudagrass monoculture pastures with(BGN)or without(BG)the application of synthetic nitrogen on forage production and stocker cattle *** Differences were observed for average daily gain(p=0.10),gain per hectare(p=0.02)and stocking rate(p=0.01),in that BGA was greatest compared to BGN and BG,which did not differ from each ***,BGA had increased forage crude protein(p=0.01)and total digestible nutrients(p=0.01)compared to BGN and ***,BGA provided the greatest economic return per hectare compared to BG or *** These data illustrate improved animal performance and forage nutritive value using alfalfa–bermudagrass systems and offer a viable option for producers seeking alternatives to synthetic N sources for bermudagrass pastures in the Southeastern United States.

关键词： alfalfa-bermudagrass mixtures forage management grazing management

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腰痛患者MRI上各节段腰椎间盘退变形式与年龄的相关性分析

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中国脊柱脊髓杂志 2009年第11期19卷 845-849页

作者：蒋欣 Yuiehiro Morishita Hymanson Henry Jeffrey c．Wang 卫生部中日友好医院骨科北京市100029 cmprehensive Spine center Department of Orthopaedic SurgeryDavid Geffen School of MedicineSanta MonicaCA U.S.A 90404

目的:探讨腰痛患者MRI上各节段腰椎间盘退变形式与年龄的相关性。方法:回顾性分析2004～2006年共529例就诊于加州大学洛杉矶分校Santa Monica骨科医院脊柱外科中心的腰痛伴或不伴有腿痛患者(男191例,女338例)的腰椎MRI资料,根据患者年... 详细信息

目的:探讨腰痛患者MRI上各节段腰椎间盘退变形式与年龄的相关性。方法:回顾性分析2004～2006年共529例就诊于加州大学洛杉矶分校Santa Monica骨科医院脊柱外科中心的腰痛伴或不伴有腿痛患者(男191例,女338例)的腰椎MRI资料,根据患者年龄分为5组,≤29岁、30～39岁、40～49岁、50～59岁及≥60岁组。按Pfirrmann′s分级系统对每例患者腰椎各节段的椎间盘(L1/2～L5/S1)退变程度进行分级,所得数据采用SPSS13.0进行统计学分析,总结其退变模式。结果:71例(13.4%)患者L1/2～L5/S1椎间盘退变程度表现为1-1-1-1-1,为正常椎间盘,是所有组合中最常见的。低年龄组发生严重退变(4级)的几率最低,L1/2、L2/3、L3/4椎间盘退变程度较L4/5、L5/S1低;1-1-1-1-1的发生率随着年龄的增加而明显降低,而1-1-1-1-2和1-1-1-1-3与之相反,发生率随着年龄的增加而明显升高。40岁以前,1-1-1-1-1的发生率最高;在40～49岁年龄组中,1-1-1-1-3的发生几率最高,为7.6%,而超过50岁,3-3-3-3-3发生的几率最高。单节段退变发生率与年龄呈负相关(P<0.01),随着年龄的增大而降低;而所有节段退变的发生率与年龄呈正相关(P<0.01),随着年龄的增大而增加。结论:在腰痛患者中,腰椎单一节段退变所占比例随年龄增大而减小,而所有节段退变所占比例随年龄增大而增大。

关键词：腰椎退行性变腰痛 MRI 分级

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Investigation on preparing boron nitride by nitriding pure boron at 1200-1550℃

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Progress in Natural Science:Materials International 2012年第5期22卷 433-439页

作者： Fang Ye a,b,Litong Zhang a,b,Yongsheng Liu a,b,Siwei Li c,Meng Su a,b,xiaowei Yin a,b,Laifei cheng a,b a Science and Technology on Thermostructural composite Materials Laboratory,Northwestern Polytechnical University,xi’an,Shaanxi 710072,PR china b State Key Laboratory of Solidification Processing,Northwestern Polytechnical University,xi’an,Shaanxi 710072,PR china c Key Laboratory of High Performance ceramic Fibers(Ministry of Education),college of Materials,xiamen University,xiamen,Fujian 361005,PR china Science and Technology on Thermostructural composite Materials Laboratory Northwestern Polytechnical University Xi''an Shaanxi 710072 PR China State Key Laboratory of Solidification Processing Northwestern Polytechnical University Xi''an Shaanxi 710072 PR China Key Laboratory of High Performance ceramic Fibers (Ministry of Education) College of Materials Xiamen University Xiamen Fujian 361005 PR China

Boron nitride(BN) was prepared by nitriding pure boron(B) deposited on carbon substrates by chemical vapor deposition(cVD).Thermodynamic analysis of preparing BN by nitriding cVD B at 1200-1550℃ was firstly *** then,the effects of nitridation conditions,including temperature,nitridation atmosphere and cVD B microstructure,on the conversion of B to BN were analyzed by scanning electron microscopy(SEM),energy dispersion spectroscopy(EDS),x-ray photoelectron spectroscopy(xPS) and transmission electron microscopy(TEM).Results show that the conversion degree of B to BN firstly increased and then slightly decreased with rising *** nitridation degree was controlled by mutual actions between the nitridation of B and consumption of the effective nitrogen source(NH3).The morphology of products and the reaction mechanism between B and N were influenced by nitridation *** high temperatures(1400-1500℃),BN with highly ordered microstructure was *** using N2-H2 as nitridation atmosphere instead of NH3-H2-N2,no BN was obtained in the studied temperature *** microstructure and component of BN obtained in nitridation process were little affected by the microstructure of cVD B.

关键词： Boron Nitridation Boron nitride Thermodynamics Kinetics

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点击化学--释义与目标

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化学进展 2008年第1期20卷 1-4页

作者： M. G. Finn Hartmuth c. Kolb Valery V. Fokin K. Barry Sharpless 张欣豪吴云东不详香港科技大学化学系香港九龙

点击化学i自2001年由Sharpless提出以来,引起广泛的重视,并得以蓬勃的发展。许多综述对此领域的进展进行了归纳ii,赵卫光,李正名等在《有机化学》中发表中文综述介绍了点击化学的一些基本概念和应用iii。作为点击化学的提出者,Sharples... 详细信息

点击化学i自2001年由Sharpless提出以来,引起广泛的重视,并得以蓬勃的发展。许多综述对此领域的进展进行了归纳ii,赵卫光,李正名等在《有机化学》中发表中文综述介绍了点击化学的一些基本概念和应用iii。作为点击化学的提出者,Sharpless最近写了一篇文章深入浅出地阐释了点击化学的思想与愿景。该文由北山隆翻译成日文,并于日本化学会的《化学と工業》发表iv。Sharpless希望此文也能以中文的形式与中国读者见面。受Sharpless之托,我们将此文翻译成中文,以冀与更多同行分享。

关键词：《有机化学》释义中文化学会综述翻译

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攻击机机群战效评估建模的系统平均动力学方法

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系统工程与电子技术 1999年第12期21卷 50-52,88页

作者：艾剑良钱国红 O.c.卡罗金西北工业大学西安710072 海军装备论证研究中心飞机论证研究所上海200436 航空系统研究院莫斯科124557

从多步骤战斗行动系统平均动力学方程出发 ,以单机种攻击机机群为研究对象 ,提出估算作战效能指标值——完成任务所需的参加战斗行动的起始攻击机架数、所需总可比费用、击毁单位目标所需平均可比费用。

关键词：攻击机作战效能动力学方程数学模型机群

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Accounting for speckle-scale beam bending in classical ray tracing schemes for propagating realistic pulses in indirect drive ignition conditions

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Matter and Radiation at Extremes 2023年第2期8卷 33-46页

作者： c.Ruyer P.Loiseau G.Riazuelo R.Riquier A.Debayle P.E.Masson-Laborde O.Morice cEA DAMDIFF-91297 ArpajonFrance cEA LMCEUniversitéParis-Saclay91680 Bruyères-le-ChâtelFrance

We propose a semi-analytical modeling of smoothed laser beam deviation induced by plasma *** on a Gaussian description of speckles,the model includes spatial,temporal,and polarization smoothing techniques,through fits coming from hydrodynamic simulations with a paraxial description of electromagnetic *** beam bending model is then incorporated into a ray tracing algorithm and carefully *** applied as a post-process to the propagation of the inner cone in a full-scale simulation of a National Ignition Facility(NIF)experiment,the beam bending along the path of the laser affects the refraction conditions inside the hohlraum and the energy deposition,and could explain some anomalous refraction measurements,namely,the so-called glint observed in some NIF experiments.

关键词： polarization beam bending

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Mechanical, thermal and fire nanoclay/vinylester retardation behaviours of nanocomposites

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Frontiers of Materials Science 2011年第4期5卷 401-411页

作者： K. R. VISHNU MAHESH H. N. NARASIMHA MURTHY B. E. KUMARA SWAMY S. c. SHARMA R. SRIDHAR Niranjan PATTAR M. KRISHNA B. S. SHERIGARA Department of P. G. Studies and Research in Industrial chemistry Kuvempu University Shankaraghatta Shimoga 577451 Karnataka India Department of Mechanical Engineering R. V. College of Engineering Bangalore 560059 Karnataka India Tumkur University Tumkur 572103 Karnataka India

The dispersion of montmorillonite （MMT） in vinylester for preparing nanoclay/vinylester gel coat was reported. Two sets of MMT/vinylester specimens, namely Type I and Type 2, were prepared for comparative studies. Type I specimens were prepared using ultrasonication only, and Type 2 specimens were prepared using both ultrasonication and twin-screw extrusion. According to xRD and TEM results, Type 2 specimens showed lower levels of nanoclay agglomeration and higher levels o! exfoliation. DSc results showed that the glass transition temperatures of Type 2 specimens are higher than those of Type 1 specimens. TGA results showed that the residual weight of 4 wt.% MMT/vinylester of Type 1 was 7.38%, while the corresponding value of Type 2 was 13,5%, indicating lower thermal degradation in the latter. MMTt vinylester/glass and MMT/vinylester/carbon specimens were fabricated and tested for mechanical and fire retardation behaviours. Type 2 based nanocomposite laminates showed greater values of ultimate tensile strength, flexural strength, interlaminar shear strength, impact strength, horizontal burning rate, and vertical burning rate than Type 1 based laminates. SEM images of tensile fractured surfaces revealed that Type 2 based laminates have no or less agglomeration of nanoclay than Type 1 based laminates.

关键词： twin-screw extrusion montmorillonite nanoclay nanocomposite vinylester

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Plant Programmed cell Death caused by an Autoactive Form of Prf Is Suppressed by co-Expression of the Prf LRR Domain

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Molecular Plant 2012年第5期5卷 1058-1067页

作者： xinran Du Min Miao xinrong Ma Yongsheng Liu Joseph c. Kuhl Gregory B. Martin Fangming xiao Department of Plant. Soil and Entomoloqical Sciences University of Idaho Moscow ID 83844. USA Ministry of Education Key Laboratory for Bio-Resource and Eco-Environment College of Life Science and State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Chengdu 610064 China chengdu Institute of Biology Chinese Academia of Sciences Chengdu 610064 China School of Biotechnology and Food Engineering Hefei University of Technology Hefei 230009 China Boyce Thompson Institute for Plant Research and Department of Plant Pathology and Plant-Microbe Biology Cornell University Ithaca NY 14853 USA

In tomato, the NBARc-LRR resistance （R） protein Prf acts in concert with the Pto or Fen kinase to determine immunity against Pseudomonas syringae pv. tomato （Pst）. Prf-mediated defense signaling is initiated by the recognition of two sequence-unrelated Pst-secreted effector proteins, AvrPto and AvrPtoB, by tomato Pto or Fen. Prf detects these inter- actions and activates signaling leading to host defense responses including localized programmed cell death （PcD） that is associated with the arrest of Pst growth. We found that Prf variants with single amino acid substitutions at D1416 in the IHD motif （isoleucine-histidine-aspartic acid） in the NBARc domain cause effector-independent PcD when transiently expressed in leaves of Nicotiana benthamiana, suggesting D1416 plays an important role in activation of Prf. The N-ter- minal region of Prf （NPrf） and the LRR domain are required for this autoactive Prf cell death signaling but dispensable for accumulation of the PrfD1416V protein. Significantly, co-expression of the Prf LRR but not NPrf, with PrfD1416v, AvrPto/Pto, AvrPtoB/Pto, an autoactive form of Pro （PtoY207D）, or Fen completely suppresses PcD. However, the Prf LRR does not in- terfere with PcD caused by Rpi-blblD475v a distinct R protein-mediated PcD signaling event, or that caused by overex- pression of MAPKKKα, a protein acting downstream of Prf. Furthermore, we found the PrfD1416V protein is unable to accumulate in plant cells when co-expressed with the Prf LRR domain, likely explaining the cell death suppression. The mechanism for the LRR-induced degradation of PrfD1416V is unknown but may involve interference in the intramo- lecular interactions of Prf or to binding of the unattached LRR to other host proteins that are needed for Prf stability.

关键词： NBARc-LRR resistance protein Prf Pto Fen AvrPto AvrPtoB cell death.

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