青藏高原3种秦艽组植物微量元素比较分析

利用全谱直读等离子体发射光谱法(ICP-AES)测定了3种秦艽组植物10种微量元素(Cu,Zn,Fe,Mn,Ni,Co,Sn,V,Al,Ti)的含量,并进行了比较分析。结果表明,所测定元素在3个不同物种内的含量排列顺序基本一致,显示了三者在元素富集方面的相似性。就同一种元素在3个物种内的富集水平而言,以麻花艽根部具有较高含量的元素Cu,Zn,Co,Al和Ti,管花秦艽根部则大量富集了其余5种微量元素,达乌里秦艽对元素的吸收积累能力居中,揭示了不同物种对同一元素富集能力的差异。该研究可为秦艽类植物资源的深入开发利用提供参考。     

青海野生抱茎獐牙菜中矿物质元素含量特征

为了对比分析青海不同地区野生抱茎獐牙菜中微量元素含量,采集花期抱茎獐牙菜全植株,采用原子吸收光谱仪分析了其铜、锌、铁、锰、钴、镍等元素含量。结果表明,不同地区野生抱茎獐牙菜中微量元素含量的变化可能与采样时间有关。     

PTFE基超声电机摩擦材料磨合阶段摩擦磨损特性研究

在超声电机运行200 h时间内,对超声电机的运行参数进行监测,采用激光共聚焦显微镜对定、转子表面粗糙度、表面形貌和磨屑特征等进行观察分析,探讨超声电机磨合期的时间及磨合期、稳定期的摩擦磨损特性.结果表明:1经过80 h磨合后,超声电机性能基本稳定.2磨合初期,摩擦材料磨损形式以黏着磨损为主,在定子表面可观测到尺寸较大的片状磨屑,进入摩擦稳定期后摩擦材料表面出现大量点蚀凹坑,表面疲劳磨损成为磨损形式之一,磨粒磨损始终存在并占重要部分;定子表面可观测到明显犁沟,磨损形式以磨粒磨损为主.3由于超声振动的存在,摩擦产生的磨屑不易在摩擦表面停留,进入稳定期后在摩擦界面难以观测到磨屑的大量存在,超声振动有排除磨屑的作用.     

气体动理学统一算法中相容性条件不满足引起的数值误差及其影响研究

求解玻尔兹曼(Boltzmann) 模型方程的气体动理学统一算法(unified gas kinetic scheme,UGKS) 是为模拟存在显著稀薄气体效应流动而建立的. 在该方法中,如果速度空间离散采用传统的离散速度坐标法(discreteordinate method,DOM),将会导致相容性条件得不到严格满足,从而引入数值误差. 本文从理论分析及数值试验两方面说明了该数值误差,正比于来流马赫数,反比于来流努森数. 引入了守恒型的离散速度坐标法(conservativediscrete ordinate method,CDOM),在离散层面上确保了相容性条件得到严格满足. 圆柱绕流计算结果表明,来流马赫数较高、努森数较小时,相容性条件满足与否对计算结果影响较大,采用CDOM 可以在较稀的速度空间网格上得到网格无关解,缩减计算量最大可达2/3.      

Effect of a barrier potential on soliton dynamical characteristics in condensates

By using the multiple-scale method, this paper analytically studies the effect of a barrier potential on the dynamical characteristics of the soliton in Bose--Einstein condensates. It is shown that a stable soliton is exhibited at the top of the barrier potential and the region of the absence of the barrier potential. Meanwhile, it is found that the height of the barrier potential has an important effect on the dark soliton dynamical characteristics in the condensates. With the increase of height of the barrier potential, the amplitude of the dark soliton becomes smaller, its width is narrower, and the soliton propagates more slowly.     

LAPECR2离子源在320kV高压平台上的试运行

The high charge state all permanent Electron Cyclotron Resonance Ion Source(ECRIS)LAPECR2 (Lanzhou All Permanent magnet ECR ion source No.2)has been successfully put on the 320kV HV platform at IMP and also has been connected with the successive LEBT system.This source is the largest and heaviest all permanent magnet ECRIS in the world.The maximum mirror field is 1.28T(without iron plug)and the effective plasma chamber volume is as large as (?)67mm×255mm.It was designed to be operated at 14.5GHz and aimed to produce medium charge state and high charge state gaseous and also metallic ion beams.The source has already successfully delivered some intense gaseous ion beams to successive experimental terminals.This paper will give a brief overview of the basic features of this permanent magnet ECRIS.Then commissioning results of this source on the platform,the design of the extraction system together with the successive LEBT system will be presented.     

近物所在产生金属离子束方面的研究

Since 1998,many experiments for metallic ion production have been done on LECR2(Lanzhou ECR ion source NO.2),LECR3(Lanzhou ECR ion source NO.3)and SECRAL(Superconductiong ECB ion source Advanced design in Lanzhou)at Institute of Modern Physics.The very heavy metallic ion beams such as those of uranium were also produced by the plasma sputtering method,and supplied for HIRFL(Heavy Ion Research Facility in Lanzhou)accelerators successfully.During the test,11.SeμAU~(28 ),9eμAU~(24 ) were obtained.Some ion beams of the metal having lower melting temperature such as Ni and Mg ion beams were produced by oven method on LECR3 too.The consumption rate was controlled to be lower for ~(26)Mg ion beams production,and the minimum consumption was about 0.3mg per hour.In this paper,the main experimental results are given.Some discussions are made for some experimental phenomena and results,and some conclusions are drawn.     

LECR2离子源的改造及初步运行结果

The Latest developed LECR2M (Lanzhou ECR No.2 Modified)source is the updated one of LECR2(Lanzhou ECR No.2)source at IMP.It has been assembled on the low energy ion beam experimental platform to produce MCI beams for atomic physics and material pllysics experimental research.In our updating program,the structure of injection and extraction components has been modified to make the source structure more simple and effective.The hexapole magnet has also been replaced by a new hexapole magnet with higher radial field and larger inner diameter.With this updating,stronger magnetic field confinement of the ECR plasma is possible and better base vacuum condition is also achieved.LECR2M was designed to be operated at 14.5GHz.During the preliminary test.1.3emA O6 beam was extracted with the injected rf power of 1.1kW.The source has been used to deliver intense MCI beams for different experiments.After some discussion of the main features of this newly updated source,some of the typical commissioning test results of LECR2M will be presented.     

悬浮固化分散液相微萃取-高效液相色谱/串联质谱法测定环境水样品中6种雌激素

本文建立了悬浮固化分散液相微萃取(DLLME-SFO)高效液相色谱-串联质谱法(HPLC-MS/MS)测定环境水样品中壬基雌酚、双酚A、己烯雌酚、雌酮、雌二醇、炔雌醇6种雌激素的分析方法。萃取的最优条件为:以90μL 1-十二醇为萃取剂,250μL0.025mol/L Triton X-100为分散剂,调节pH至7.0,超声3min,在室温条件下萃取环境水样中的雌激素残留。最优条件下,该方法在三个浓度水平下的平均加标回收率为93.4%~108.6%,相对标准偏差为1.3%~8.7%,检出限为0.001~0.05μg/L。将该方法应用于环境水样中雌激素残留分析,获得了较好的回收率。     

pH值对水热合成黄铁矿型CoS2微晶的影响

本文以EDTA-2Na为辅助剂,Na2S2O3.5H2O为硫源,运用水热法制备了黄铁矿型CoS2微晶,研究了溶液pH值对产物结构和形貌的影响。采用X射线粉末衍射仪(XRD),扫描电子显微镜(SEM)对产物的结构和形貌进行了表征。实验结果表明,溶液为酸性环境时(pH=1、3)可得到纯相的黄铁矿型CoS2微晶,形貌为微米尺寸的空心球壳。溶液为中性和碱性环境时(pH=7、11),产物出现少量杂相,形貌变为规则的八面体晶粒。讨论了这些CoS2微晶的形成机制。