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1.
直流清洗电场对储存环聚焦参数修正作用的研究   总被引:1,自引:0,他引:1  
研究了直流清洗电场对储存环聚焦参数的修正作用.认为该清洗电场形成的横向振荡数移位,与储存束流闭轨实时位置有关.指出电极沿环不对称分布的此类清洗电场,会破坏储存环聚焦结构的对称性,降低储存环的接受度,在一定条件下,对注入积累束流过程有负作用.  相似文献   

2.
针对HL-2M装置初始等离子体放电阶段所需的直流辉光放电清洗系统的电极进行了设计.对辉光放电清洗系统在不同工况下的系统负载进行了分析和拟定,并确定了电极结构设计分析标准.根据系统电极的结构特点并结合系统负载规范与分析标准,依据不同的失效模式对电极进行了失效分析.分析结果表明,此针对初始等离子体放电的电极设计能可靠安全运...  相似文献   

3.
基于直流—射频电极结构对离子的径向和轴向聚焦理论,以离子检测仪器中质子转移反应质谱检测技术为例,对该新型电极结构展开理论和实验研究,相比于静电场电极结构,直流—射频聚焦电场电极结构的性能更好,丙酮产物离子强度提高了近10倍,初步的实验结果表明该结构对于提高离子相对透过率具有较大潜力,同时,该新型直流—射频聚焦电场电极结构对于提高其他类型的离子检测仪器性能将具有一定的应用潜力和参考价值.  相似文献   

4.
基于 HL-2M 托卡马克初始等离子体放电的工程需求,设计并研制了直流辉光放电清洗系统,包括电 极、馈线、电源、控制以及监测等关键部件和辅助子系统。研制完成后开展了系统装配和工程调试,并投入到首 次等离子体放电。实验结果表明,该直流辉光放电系统运行稳定、可靠,且此辉光放电清洗显著降低了真空室本 底杂质浓度,能满足 HL-2M 装置初始等离子体放电的壁条件需求。  相似文献   

5.
合肥光源储存环的离子俘获与直流离子清洗   总被引:2,自引:0,他引:2  
研究了合肥光源(HLS)电子储存环中离子产生、俘获的过程,离子对束流的影响,直流离子清洗的作用及清洗效果.为光源的高效率的运行提供了理论指导及实验依据.  相似文献   

6.
李世松  张钟华  赵伟  黄松岭  傅壮 《物理学报》2015,64(6):60601-060601
提出了一种用于弱力测量的带电Kelvin电容器产生静电力的新型工作方式. 该工作方式的优点是在机械上可明显简化静电力的实现, 避免了带电Kelvin电容器在传统工作方式下需要同步移动中心电极和保护电极的困难; 缺点是因Kelvin 电容器的边缘效应, 会不可避免地随之产生一个小的静电力分量, 需要准确建立它的数学模型, 方可清晰地评估它对测量结果的影响. 为解决此问题, 本文采用部分电容模拟和保角变换, 将二维电场的计算转换为一维电场计算问题, 并基于此, 得到了一种合理表征Kelvin电容器边缘效应所产生静电力分量的解析模型. 通过与一个具体计算实例的有限元计算求解结果相比较, 分析了所建立的解析模型的准确性.  相似文献   

7.
静电电压表对测量交直流高压有着非常重要的作用。为了实现高电压静电电压表的精确测量,提出并制备了一种采用法布里珀罗(FP)腔干涉原理的静电电压传感器。所设计的传感器电极与高压电极构成一组静电电压测量电极,此传感器的FP腔由光纤准直器和外侧镀铝的聚酯膜构成,当在高压电极施加载荷时,聚酯膜与高压电极之间产生均匀电场,在电场力作用下聚酯膜产生形变,从而改变FP腔的腔长,造成FP传感器的输出光谱偏移,采用相位解调法获得高压电极上施加的载荷,实现电压的静电测量。实验结果表明:可实现5~16kV直流高压和交流高压有效值的测量,5~10kV范围测量精度为1.21%,10~16kV的测量精度为0.61%。此传感器满足高电压的测量要求。  相似文献   

8.
60kV,55A,2S桶式离子源的物理设计和工程设计已基本完成,目前的设计是基于引出.加速.减速电极系统结构进行的,它们分别是:引出电极、加速电极、抑制电极和地电极。在抑制极与地电极间的抑制区域,离子束与电极问本底气体进行电荷交换产生的离子和束电离本底气体产生的离子经电场加速后轰击到地电极栅上,产生束能量的沉积,从而导致电极栅温度升高,并产生热变形。若温度过高,将可能导致冷却管道熔化,冷却剂渗漏。若热变形过大,还将会影响束的离子光学性能。为了保证电极栅的机械可靠性和几何非塑性变形,需要对它进行热应力分析。  相似文献   

9.
通过对HL-1M装置的氦直流辉光放电清洗(He-GDC)的放电特点和清除率的研究,发现环形真空室的对称性导致与阳性截面对称的区域的场强很弱,使其阴极位降区的厚度大于氦离子的平均自由程,严重影响清除率,因此提出了要用多电极不对称阳极电位的辉光放电来提高清除率,同时发现,辉光放电清洗使氢分压比托马克放电的送氢代压强代一个量级上,才能重复进行好的有辅助加料的托卡马放电。  相似文献   

10.
通过对HL-1M装置的氦直流辉光放电清洗(He-GDC)的放电特点和清除率的研究,发现环形真空室的对称性导致与阳极截面对称的区域的场强很弱,使其阴极位降区的厚度远大于氦离子的平均自由程,严重影响清除率,因此提出采用多电极不对称阳极电位的辉光放电来提高清除率;同时发现,辉光放电清洗使氢分压比托卡马克放电的送氢压强低一个量级以上,才能重复进行好的有辅助加料的托卡马克放电。  相似文献   

11.
工作点测量系统在合肥光源的应用研究   总被引:1,自引:0,他引:1       下载免费PDF全文
 介绍了利用合肥光源(HLS)的工作点测量系统进行一些束流参数的测量及其应用研究,这些参数包括工作点、β函数;自然色品以及中心频率。同时还进行了清洗电极对工作点的影响的测量。给出了一些测量结果,测量结果与理论计算值相当吻合。  相似文献   

12.
Electrohydrodynamics (EHD) conduction pumping takes advantage of Coulomb force generated by externally applied electric field and dissociated charges from electrolytes present in the working fluid. With the electric field maintained below the DC breakdown limit (i.e voltage required for charge injection), EHD conduction generated flow relies primarily upon the asymmetry of the electrodes where the flow is always generated toward the specific direction regardless of the electrodes polarity. The charge distribution induced by the process of dissociation may be altered by charge injection, potentially present at the electrodes' surfaces. The charge injection could occur, for example, because of the electrode surface roughness.This paper is a numerical investigation to quantify the impact of the charge injection on the performance of EHD conduction pump. The numerical domain comprises a coplanar asymmetric electrode pair embedded against a 2-D channel wall where the EHD conduction induced liquid flow is expected to be generated from the narrower electrode toward the wider electrode in the absence of charge injection. The electric field, net charge density, and electric body force distributions are presented in the absence and presence of charge injection. In addition, the electrically generated net flow is calculated for several operating conditions.  相似文献   

13.
A semianalytical model for capacitively coupled radio frequency (RF) sheaths of asymmetric (unequal electrode area) systems has been developed. It can be applied in the high-frequency (ω > ω pi) regime at different pressures. An analytical approximation to the pressure-dependent ion density profile is used. The time-varying electric field and potential within the sheath are obtained by solving Poisson's equation. The current balance and zero net DC current conditions are applied to solve for the RF sheath parameters and DC bias voltage. The DC voltage ratio between the powered and grounded electrode sheaths increases as the pressure decreases, which results in a larger DC bias voltage at lower pressures  相似文献   

14.
A conducting drop in partial wetting on the lower electrode of a plate condenser and surrounded by a dielectric fluid is considered. When a DC field is applied the drop, acquiring electric charges, is subjected to an electrostatic force normal to the electrode. The force exerted on undeformable drops was previously calculated. In this paper, the distortion from a spherical shape is asymptotically calculated at low electric Bond numbers to generalize previous developments. A mechanism is proposed to explain the drop detachment, leading to an electrical field strength threshold. Some experiments were performed confirming the mechanism.  相似文献   

15.
为探讨原位条件下关节软骨及下骨组织成分含量变化等深层次微观信息,采用拉曼光谱技术结合组织光透明技术来研究软骨组织的光透明效果。选用甘油、碘海醇作为光透明剂,对在不同光透明剂浓度和浸渍时间下的犬膝关节股骨端软骨样本进行拉曼光谱采集。通过计算磷酸基团(920~960 cm-1 ) 和酰胺Ⅰ带(1 595~1 700 cm-1)的积分强度,获得拉曼强度比(磷酸基团/酰胺Ⅰ),探索在不同浸渍时间(10~60 min)、不同浓度下(甘油40%,60%,80%和100%,碘海醇50,150,250和350 mg·mL-1)组织光透明的规律,即寻找合适的透明浓度和透明时间。结果显示:相比于无透明剂情形,两种透明剂均使该强度比信号增强。在同一时间范围内,甘油和碘海醇分别在60%和150 mg·mL-1 浓度下能获得较好的透明效果;而在不同浓度下,甘油的透明效果均在20 min最强,而碘海醇的透明效果一般是在50 min后开始增强。在光透明剂的作用下激发光透过软骨可以直接探测到软骨下骨的拉曼光谱信息,这为研究骨关节炎深层次病因提供了方法和思路。  相似文献   

16.
In order to find a non-invasive way to improve the efficacy of skin optical clearing with topically applied optical clearing agents (OCA), we evaluated the effect of Azone as a chemical penetration enhancer on optical clearing of intact skin in vitro. Fresh porcine skin with topical application of glycerol (G) mixed with various concentrations of water-soluble Azone (Aw) or propylene glycol (PG) mixed with oil-soluble Azone (Ao) was investigated. We measured changes in optical transmittance and diffuse reflectance of the skin under treatment with a near-infrared spectrophotometer. Light transmittance at 1276 nm increased by 37.3% and 41.1% at 60 min after the treatment in the cases with 40%PG5%Ao and 40%G5%Aw, respectively. Diffuse reflectance at 1066 nm decreased by 20.6% and 29.3% at 60 min after the treatment with 40%PG5%Ao and 40%G5%Aw, respectively. Forty percent glycerol or propylene glycol with the addition of Azone could achieve the same optical clearing effect as 80% glycerol. The results indicated that skin optical clearing with the topical application of glycerol and propylene glycol was markedly enhanced by both water-soluble and oil-soluble Azone. Skin penetration enhancing effect of Azone accounts probably for the skin clearing enhancement. In addition, Azone itself has shown optical clearing capability.  相似文献   

17.
We investigate the discharge and flow characterizations of a double-side siding discharge plasma actuator driven by different polarities of direct current(DC) voltage. The discharge tests show that sliding discharge and extended discharge are filamentary discharge. The irregular current pulse of sliding discharge fluctuates obviously in the first half cycle,ultimately expands the discharge channel. The instantaneous power and average power consumptions of sliding discharge are larger than those of the extended discharge and dielectric barrier discharge(DBD). The flow characteristics measured by a high-frequency particle-image-velocimetry system together with high-speed schlieren technology show that the opposite jet at the bias DC electrode is induced by sliding discharge, which causes a bulge structure in the discharge channel.The bias DC electrode can deflect the direction of the induced jet, then modifying the properties of the boundary layer.Extended discharge can accelerate the velocity of the starting vortex, improving the horizontal velocity profile by 203%.The momentum growth caused by extended discharge has the largest peak value and the fastest growth rate, compared with sliding discharge and DBD. However, the momentum growth of sliding discharge lasts longer in the whole pulsed cycle,indicating that sliding discharge can also inject more momentum.  相似文献   

18.
Flow actuation by a continuous/pulsed, direct-current (DC) surface glow discharge is explored. The discharge comprises an array of pin electrode pairs flush mounted on a dielectric actuator surface that lies adjacent to stagnant air. Strong electrostatic fields produced in the cathode sheath region of the discharge provides a motive force on the ions which in turn drag the background gas resulting in directed air flow from the anode to the cathode. The induced flow velocity is estimated by particle image velocimetry (PIV) at 10 Hz with TiO2 seeding. For a pulsed DC discharge with peak power of 5 W per electrode pair, the induced flow velocity reaches peak values of about 1.7 m/s which is comparable to dielectric-barrier discharge (DBD) or corona discharge actuators. The actuation effect quantified by the magnitude of induced velocity increases as the pulse frequency increases from 0 to 1 kHz. The actuation effect decreases for further increase in frequency above 1 kHz. Decreased actuation effect at high frequency is accompanied by structural change in the discharge. At fixed frequency of 1 kHz, flow actuation effect is highest for a square wave pulse with a duty cycle of 50% indicating that pulsed DC discharges produces better actuation than continuous DC with a corresponding reduction in energy consumption.  相似文献   

19.
毛宗珍  胡亚婷  郑英  陆为  骆清铭   《光学学报》2007,27(3):526-530
研究一种新型促渗剂——噻酮对皮肤组织光透明效果的影响。分别用单纯聚乙二醇400(PEG400)溶液以及PEG400与噻酮的混合溶液作用于含角质层及去角质层的离体乳猪皮肤,利用积分球系统动态检测样品对632.8 nm光的透射率变化,并对样品拍照获得直观图。结果表明:混合溶液作用于两种皮肤模型后,其光透明性均有不同程度的增加,即衰减系数降低;比较去角质层皮肤与含角质层皮肤的衰减系数的变化,前者比后者大19倍;单纯的PEG400仅对去角质皮肤有一定的光透明效果,并且所导致的皮肤衰减系数的降低仅为混合液作用后的2/3。因此,噻酮作为良好的促渗剂能与PEG400产生协同效应,有效提高皮肤光透明效果。  相似文献   

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