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Chemical Composition of Root and Stem Saps in Relation to Cadmium Resistance and Accumulation in Brassica parachinensis

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Pedosphere 2007年第3期17卷 352-359页

作者： WU Qi-Tang XU Zhao-Li YE Hui j. W. C. WONG College of Natural Resources and Environment South China Agricultural University Guangzhou 510642 （China） Department of Biology Hong Kong Baptist University Kowloon Tong Hong Kong SAR （China）

Sap mixtures of the xylem, phloem, and vacuoles from low and high Cd accumulator varieties of Brassica parachinensis L. H. Bailey were analyzed under Cd stress to understand the biochemical mechanisms of Cd accumulation in plants. Low Cd accumulator ('Teqing-60') and high Cd accumulator ('Chixin-2') plants were grown in Cd-treated soil in pots in a greenhouse. Percentage of cell wall-bound Cd was estimated. pH level and the concentrations of amino acids, organic acids, anions, and cations in both stem and root saps were determined for the calculation of Cd speciations using the computer program GEOCHEM. The results showed that 'Teqing-60' had a significantly higher (P≤0.05) percentage of Cd bound to cell walls in roots and a significantly higher (P≤0.05) pH in the root sap. 'Teqing-60' also contained a higher concentration of total amino acids in both roots and stems compared with the high Cd accumulator variety 'Chixin-2'. However, between the two accumulators, for stems and for roots, there were no significant differences in non-amino organic acids. GEOCHEM calculations showed that Cd in the root sap of 'Teqing-60' mainly combined with amino acids, especially alanine. Compared with 'Chixin-2', in the root sap of 'Teqing-60', much lower levels of Cd as free ions or bound to simple ligands were found, indicating that less 'Teqing-60' is transferred to stems and leaves. Cadmium activity in the shoot sap of 'Teqing-60' was much lower than that in 'Chixin-2'; therefore, 'Teqing-60' exhibited higher Cd resistance. However, direct determination of the Cd complexes from xylem and phloem sap is needed to verify these results.

关键词： Brassica parachinensis cadmium plant sap resistance speciation

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滴状向射流模式转变的试验研究

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江苏大学学报（自然科学版） 2024年第5期45卷 544-550页

作者：王贞涛薛佳怡孔茜李睿杨诗琪李彬江苏大学能源与动力工程学院江苏镇江212013 莱宝(天津)国际贸易有限公司天津300000

液体通过内径细小的喷嘴或孔口排到周围介质中,当出口压力或流量增大时,液体在毛细管末端出流的模式将从周期滴状(PD)向混乱状态(DF)再向射流状态(j.进行转变.通过改变注射泵的流量,运用高速数码相机分别记录了去离子水和无水乙醇毛细... 详细信息

液体通过内径细小的喷嘴或孔口排到周围介质中,当出口压力或流量增大时,液体在毛细管末端出流的模式将从周期滴状(PD)向混乱状态(DF)再向射流状态(j.进行转变.通过改变注射泵的流量,运用高速数码相机分别记录了去离子水和无水乙醇毛细管雾化的3种典型雾化状态(滴状、混乱、射流),获得雾化状态转变时的临界韦伯数,结果表明:在周期滴落过程中,随着孔口内径增加,液滴的形态会由球形逐渐变为梨形;随着流量的增加,两种流体均从滴状模式经过混乱状态,逐渐到达射流模式;与去离子水相比不同的是,无水乙醇的过渡状态存在范围较小,只存在于内径为0.33~0.60 mm,并且极易从周期滴状模式直接过渡到射流模式;去离子水和无水乙醇雾化模式转变的差异是两种流体的表面张力不同所致,其滴状到射流模式转变对应的临界韦伯数能够实现雾化模式转换过程的预测.

关键词：液体滴状射流转变过程韦伯数

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New Alkaloids from the Rhizomes of Goniothalamus Griffithii

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Chinese Chemical Letters 1998年第11期9卷 0-0,0-0页

作者： Zhang Y.j. kong M. Chen R.Y. Yu D.Q. Institute of Materia Medica Chinese Academy of Medical Sciences Peking Union Medical College Beijing 100050 China

Three new alkaloids, griffithdionc 1, griffiazanone A 2 and griffiazanone B 3 were isolated from the rhizomes of Goniothalamus griffithii Hook. F. el. Thoms. Their structures were elucidated by analysis the spectral data (IR, UV, MS, 1 H and 13C NMR, HMBC, NOE experiment).The absolute configuration of griffithazanone A 2 was determined by Mosher's methods.

关键词： Goniothalamus griffithii phenanthrene lactam alkaloids griffithdione griffiazadioneA and griffiazadione B

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Classification of extremely red obj.cts in the Hubble Ultra Deep Field

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Chinese j.urnal of Astronomy and Astrophysics 2009年第1期9卷 59-72页

作者： Guan-Wen Fang Xu kong Min Wang Center for Astrophysics University of Science and Technology of China Hefei 230026 China j.int Institute for Galaxy and Cosmology （j.INGC） of S HAO and USTC

We present a quantitative study of the classification of Extremely Red Obj.cts （EROs）. The analysis is based on the multi-band spatial- and ground-based observations （HST/ACS-BViz, HST/NICMOS-j., VLT-j.K） in the Hubble Ultra Deep Field （UDF）. Over a total sky area of 5.50 arcmin2 in the UDF, we select 24 EROs with the color criterion （i - K）vega 〉 3.9, corresponding to （I - K）vega 〉～4.0, down to Kvega = 22. We develop four methods to classify EROs into Old passively evolving Galaxies （OGs） and Dusty star-forming Galaxies （DGs）, including （i - K） vs. （j.- K） color diagram, spectral energy distribution fitting method, Spitzer MIPS 24 um image matching, and nonparametric measure of galaxy morphology, and found that the classification results from these methods agree well. Using these four classification methods, we classify our EROs sample into 60Gs and 8 DGs to KVega 〈 20.5, and 80Gs and 16 DGs to KVega 〈 22, respectively. The fraction of DGs increases from 8/14 at KVega 〈 20.5 to 16/24 at KVega 〈 22. TO study the morphology of galaxies with its wavelength, we measure the central concentration and the Gini coefficient for the 24 EROs in our sample in HST/ACS-i, z and HST/NICMOS-j. H bands. We find that the morphological parameters of galaxies in our sample depend on the wavelength of observation, which suggests that caution is necessary when comparing single wavelength band images of galaxies at a variety of redshifts.

关键词： galaxies evolution - galaxies fundamental parameters - galaxies highredshift - cosmology observations

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Perpulmonary Device Closure of Patent Ductus Arteriosus with Minimum Diameter More Than 4 mm in Infants

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Congenital Heart Disease 2022年第4期17卷 437-445页

作者： Shibin Sun Geoffrey j.Changwe Zeeshan Farhaj.Hongxin Li Yuekun Sun Zhongzheng kong Department of Cardiovascular Surgery Shandong Qianfoshan HospitalCheeloo College of MedicineShandong UniversityJinanChina Department of Cardiovascular and Thoracic Surgery The National Heart HospitalLusakaZambia

Background:Closure of large patent ductus arteriosus(PDA)in older children has been accomplished using surgical and percutaneous techniques with remarkable ***,outcomes amongst infants have been variable with several *** we describe a novel minimally invasive technique,a product of mini-thoracotomy and traditional percutaneous technique skills,accomplished exclusively under echocardiography ***:Symptomatic infants with a significant left-to-right shunt from PDA measuring more than 4 mm were *** symptoms were varying degrees of tachypnea,tachycardia,heart failure,failure to thrive,recurrent respiratory tract infections,or intensive care unit treatment for a longer *** a left parasternal mini-thoracotomy,two parallel purse-string sutures were placed on the pulmonary *** purse-string circle puncture,under exclusively transesophageal echocardiography guidance,a device secured to the safety-suture was implanted on the ascending aorta via pulmonary trunk using a specially designed *** safety-suture prevented device migration in case of *** basic demographics,PDA size,device size and type,intrapulmonary manipulation time,operation time,PDA parameters(length,diameter,type of duct),redeployment of the device,residual shunt,and retention of safety-suture were all recorded and *** follow-up was done with transthoracic echocardiography on the 2^(nd)postoperative day,1,3,6,and 12 months,and yearly ***:Fifty-two infants with a mean age of 8 months±2.8 months(Interquartile range=0)underwent Perpulmonary device closure of *** PDA occlusion was accomplished event-free in all *** mean PDA,mean device,and mean operation time were 5.6 mm±1.4 mm,7.9 mm±1.7 mm,and 61.2 min±12.9 min,*** immediate acceptable residual shunt was noted among 3 subj.cts and disappeared at a 1-month *** infants had retained safety-suture for added ***

关键词： Patent ductus arteriosus perpulmonary device closure transesophageal echocardiography infant minimally invasive surgery

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Improved thermal conductivity and breakdown strength of PVDF-based composites by improving the dispersion of BN

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High Voltage 2022年第3期7卷 595-605页

作者： Yanxin Li Zhuo Wang Menglei kong Zhihui Yi School of Materials Science and Engineering Shaanxi Key Laboratory of Green Preparation and Functionalization for Inorganic MaterialsShaanxi University of Science and TechnologyXi'anChina

In order to adapt to the development of electronic devices,it is necessary to improve the thermal conductivity and breakdown strength of *** nitride(BN)is an ideal candidate material with high breakdown strength and thermal ***-fore,the introduction of BN nanosheets into the polyvinylidene fluoride(PVDF)matrix can improve the thermal conductivity and breakdown strength of the composites at the same ***,BN nanosheets can easily agglomerate in the matrix,which limits the improvement of the properties of the *** overcome this difficulty,appropriate water-bath heating was used to improve the fluidity of ***,the dispersion of the filler is *** the volume fraction of BN nanosheets is 3%and the preparation temperature is 45℃,the energy storage density of the compos-ites reached 18.5 j.cm^(3) at 540 kV/*** this point,the thermal conductivity was 0.49 W/(m⋅K),3.5 times that of the pure PVDF film.

关键词： composites conductivity strength

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微分中值定理中思政元素的探讨

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山西大同大学学报（自然科学版） 2024年第3期40卷 60-62,100页

作者：贾艳萍孔丽丽山西大同大学数学与统计学院山西大同037009

数学分析课程不仅传授数学知识,而且蕴含着丰富的思政元素。以微分中值定理教学为例,通过细致解读三大中值定理的核心内容,并结合实际问题中的应用,巧妙地融入哲学思想、价值观教育和科学家精神等思政元素。在教学实践中,通过将思想政... 详细信息

数学分析课程不仅传授数学知识,而且蕴含着丰富的思政元素。以微分中值定理教学为例,通过细致解读三大中值定理的核心内容,并结合实际问题中的应用,巧妙地融入哲学思想、价值观教育和科学家精神等思政元素。在教学实践中,通过将思想政治教育与数学分析教学的有机结合,旨在培养学生的数学思维品质,使其树立正确的世界观、人生观和价值观,同时激发学生对数学分析课程的学习兴趣和热情。

关键词：数学分析微分中值定理思政元素

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Influence of adiabatic response of passing energetic ions on high-frequency fishbone

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Plasma Science and Technology 2022年第9期24卷 24-30页

作者： Haozhe kong Feng WANG j.zhong SUN School of Physics Dalian University of TechnologyDalian 116024People’s Republic of China

Adiabatic response effects on high-frequency flshbone instability driven by passing energetic ions are *** flnite orbit width effects,the adiabatic contributionδW_(hf)is derived analytically for purely passing energetic *** approximating the adiabatic contribution to the flrst order of the reverse aspect ratioε,we derive one of its analytic expressions,which is expected to be more accurate than that in a previous work(Graves j.P 2004 ***.92185003).For high-frequency flshbone instability,nonadiabatic response is usually dominant over adiabatic response,but under certain circumstances the latter plays an important role,comparable to the *** a more generalized distribution function by introducing Gaussian-type factors representing their pitch and radial dependences and using a slowing-down equilibrium distribution for the energy of energetic ions,numerical analysis indicates that the adiabatic contribution is conducive to stabilization of the mode and causes a decrease in mode *** addition,we flnd that the adiabatic contribution has a weak stabilizing effect on the flshbone instability when the flnite orbit width effect is taken into *** further analyze the dependence of the adiabatic contribution on the characteristic parameters of the distribution *** the neutral beam has either a larger deviation from the plasma axis or a larger radial proflle,the adiabatic contribution has a more evident effect on the flshbone *** the neutral beam has a relatively small critical energy,the adiabatic contribution has a greater effect on the mode instability.

关键词： flshbone passing particle adiabatic response tokamak

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可变论域信息粒和粗糙集的数字特征

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集美大学学报（自然科学版） 2024年第3期29卷 262-270页

作者：常雪尔孔庆钊王婉婷集美大学理学院福建厦门361021

为了更准确直观地刻画信息粒,从数字描述的角度,研究可变论域信息表中信息粒和粗糙集的个数,以及信息粒空间和粗糙集空间的基、维数等数字特征。

关键词：信息粒可变论域粗糙集数字特征

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High-entropy FeNiCoCr alloys with improved mechanical and tribological properties by tailoring composition and controlling oxidation

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j.urnal of Materials Science & Technology 2021年第23期82卷 207-213页

作者： j.e Xu Xuan kong Minghui Chen Qunchang Wang Fuhui Wang Shenyang National Laboratory for Materials Science Northeastern UniversityShenyang110819China

Many metal matrix self-lubricating composites possess excellent comprehensive properties of high strength and wear resistance after incorporating various lubricants that usually belong to ceramic ***,this improvement is always obtained at the cost of notable decrease in *** order to break through this toughness-tribological properties trade-off,self-lubricating composite alloys based on the matrix of Fe NiCoCr_(0.5) high entropy alloy(HEA)were prepared by milling addition of element Co or Cr and then spark plasma sintering(SPS).Co or Cr is added into the base HEA with the aim of tailoring oxidation behavior,mechanical properties as well as tribological *** no ceramic lubricants are used,the alloy composites remain high *** or Cr element addition leads to the precipitation of a hard phase of a-Cr and grain refinement,both of which contribute to the increase of mechanical *** sliding,oxidation of Fe and Ni is ***,the oxides of cobalt and chromium are formed upon the Co-and Cr-modified HEAs,*** oxidation products,especially the oxides of cobalt that are easy to be sintered on sliding,are in favor of the formation of a lubricating glaze layer at 400℃on the worn surface,and thus the decrease in friction coefficient and wear rate,which are 0.33 and 4.0×10^(-5) mm^(3)/(N m),respectively.

关键词： High entropy alloys Oxidation behavior Self-lubricating composite Cobalt oxide

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