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Effect of ion-beam assisted deposition on the film stresses of TiO_2 and SiO_2 and stress control 被引量:3
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作者 Yu-Qiong Li Hua-Qing Wang +3 位作者 Wu-Yu Wang Zhi-Nong Yu He-Shan Liu Gang Jin 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2012年第5期1382-1388,共7页
Based on Hartmann-Shack sensor technique, an online thin film stress measuring system was introduced to measure the film stresses of TiO2 and SiO2, and comparison was made between the film stresses prepared respective... Based on Hartmann-Shack sensor technique, an online thin film stress measuring system was introduced to measure the film stresses of TiO2 and SiO2, and comparison was made between the film stresses prepared respectively by the conventional process and the ion-beam assisted deposition. The effect of ion-beam assisted deposition on the film stresses of TiO2 and SiO2 was investigated in details, and the stress control methodologies using on-line adjustment and film doping were put forward. The results show that the film stress value of TiO2 prepared by ion-beam assisted deposition is 40 MPa lower than that prepared by conventional process, and the stress of TiO2 film changes gradually from tensile stress into compressive stress with increasing ion energy; while the film stress of SiO2 is a tensile stress under ion-beam assisted deposition because of the ion-beam sputtering effect, and the film refractive index decreases with increasing ion energy. A dynamic film stress control can be achieved through in-situ adjustment of the processing parameters based on the online film stress measuring technique, and the intrinsic stress of film can be effectively changed through film doping. 展开更多
关键词 Film stress Stress controlling ion-beam as-sisted deposition Hartmann-Shack sensor
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Effects of the ion-beam voltage on the properties of the diamond-like carbon thin film prepared by ion-beam sputtering deposition 被引量:1
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作者 孙鹏 胡明 +4 位作者 张锋 季一勤 刘华松 刘丹丹 冷健 《Chinese Physics B》 SCIE EI CAS CSCD 2015年第6期581-585,共5页
Diamond-like carbon (DLC) thin film is one of the most widely used optical thin films. The fraction of chemical bondings has a great influence on the properties of the DLC film. In this work, DLC thin films are prep... Diamond-like carbon (DLC) thin film is one of the most widely used optical thin films. The fraction of chemical bondings has a great influence on the properties of the DLC film. In this work, DLC thin films are prepared by ion-beam sputtering deposition in Ar and CH4 mixtures with graphite as the target. The influences of the ion-beam voltage on the surface morphology, chemical structure, mechanical and infrared optical properties of the DLC films are investigated by atomic force microscopy (AFM), Raman spectroscopy, nanoindentation, and Fourier transform infrared (FTIR) spec- troscopy, respectively. The results show that the surface of the film is uniform and smooth. The film contains sp2 and sp3 hybridized carbon bondings. The film prepared by lower ion beam voltage has a higher sp3 bonding content. It is found that the hardness of DLC films increases with reducing ion-beam voltage, which can be attributed to an increase in the fraction of sp3 carbon bondings in the DLC film. The optical constants can be obtained by the whole infrared optical spectrum fitting with the transmittance spectrum. The refractive index increases with the decrease of the ion-beam voltage, while the extinction coefficient decreases. 展开更多
关键词 DLC thin film ion-beam sputtering deposition chemical bondings infrared optical and mechani-cal properties
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Bioeffects of Low Energy Ion-Beam Implantation and Vacuum Treatment on M_1 Arabidopsis Thaliana
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作者 杨根 卞坡 +3 位作者 张正红 任杰 吴李君 余增亮 《Plasma Science and Technology》 SCIE EI CAS CSCD 2006年第2期242-246,共5页
Vacuum treatment and ion-beam bombardment are two major processes in the low energy ion-beam implantation. To accurately study the contributions of these two major factors to the bioeffects separately, the M1 generati... Vacuum treatment and ion-beam bombardment are two major processes in the low energy ion-beam implantation. To accurately study the contributions of these two major factors to the bioeffects separately, the M1 generation variation of Arabidopsis thaliana with ion-beam implantation and vacuum treatment were compared through a series of key plant development parameters including morphological observation, biochemical assay and RAPD (random amplified polymorphic DNA) analysis. The results showed that ion-beam implantation had obvious effect on almost all of these parameters, and the vacuum treatment had some impacts on several morphological parameters such as the bolting time and the length of the primary stem. Taking the results together, the indication is that vacuum treatment has some slight contributions to the bioeffects of ion-beam implantation while ion-beam bombardment itself is the major creator of the bioeffects. 展开更多
关键词 BIOEFFECTS ion-beam VACUUM Arabidopsis thaliana
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Ion-Beam Surface Modification of Strut Dowel Used in ITER PF Support
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作者 罗蓉蓉 李鹏远 +4 位作者 韩石磊 孙振超 潘传杰 沈丽茹 金凡亚 《Plasma Science and Technology》 SCIE EI CAS CSCD 2013年第3期303-306,共4页
In this paper, surface modification of the strut dowel used in ITER PF support is reported. Different ions (nitrogen/titanium) with different doses are implanted into the surface of strut dowel. The result of Auger ... In this paper, surface modification of the strut dowel used in ITER PF support is reported. Different ions (nitrogen/titanium) with different doses are implanted into the surface of strut dowel. The result of Auger Electron Spectroscopy (AES) indicates that nitrogen can be implanted more deeply than titanium under the implantation condition of 60 kV accelerating voltage and a dose of 8×10^17/cm2 nitrogen. Surface Micro Hardness (SMH) and wear resistance are improved remarkably. Further SEM observation shows that there are no obvious scratches and damages after wear test. 展开更多
关键词 ITER PFCS dowel ion-beam implantation
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Studies on Ion-Beam Modified Hydrogen Evolution Electrodes
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作者 Zhang Ji-shuang Li Qin-lian Lu Yao-jiao and Yan Xi-yun (Department of Chemistry and Chemical Engineering, Hunan Univesity, Changsha, 410082) Hou Rang-kun (Deaprtment of Chemistiy , Henan Educational College, Zhengzhou, 450003 ) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1994年第2期68-71,共4页
he present paper focuses on the modifying effects of ion beam mixing, ion im-planting and ion sputtering on hydrogen evolution electrodes. It was discovered thatthe four types of electrodes possessed excellent catalyt... he present paper focuses on the modifying effects of ion beam mixing, ion im-planting and ion sputtering on hydrogen evolution electrodes. It was discovered thatthe four types of electrodes possessed excellent catalytic activity in acid or alkalinemedia and potential stability in long term electrolysis of water under high currentdensity. Their stability and applying life-span greatly surpass those of other elec-trodes activated by electrodepositing and other method. The effects of temperatureand roughness on function of electrodes were also examined. XPS and AES wereapplied to analyse the surface composition and bond states of the electrodes, andthe distribution of concentration varying with depth, and to explain the law of theexperiments . 展开更多
关键词 Implantating ion-beam Mixing Ion Sputtering XPS Hydrogen Evo-lution Reaction
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Poloidal magnetic field reconstruction by laser-driven ion-beam trace probe in spherical tokamak
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作者 Zuyu ZHANG Tianchao XU +4 位作者 Chijie XIAO Xianli HUANG Renchuan HE Ruixin YUAN Xiaoyi YANG 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第11期58-64,共7页
The poloidal magnetic field( B_(p)) plays a critical role in plasma equilibrium, confinement and transport of magnetic confinement devices. Multiple diagnostic methods are needed to complement each other to obtain a m... The poloidal magnetic field( B_(p)) plays a critical role in plasma equilibrium, confinement and transport of magnetic confinement devices. Multiple diagnostic methods are needed to complement each other to obtain a more accurate B_(p) profile. Recently, the laser-driven ion-beam trace probe(LITP) has been proposed as a promising tool for diagnosing B_(p) and radial electric field( E_(r)) profiles in tokamaks [Yang X Y et al 2014 Rev. Sci. Instrum. 85 11E429]. The spherical tokamak(ST) is a promising compact device with high plasma beta and naturally large elongation. However, when applying LITP to diagnosing B_(p) in STs, the larger B_(p) invalidates the linear reconstruction relationship for conventional tokamaks, necessitating the development of a nonlinear reconstruction principle tailored to STs. This novel approach employs an iterative reconstruction method based on Newton's method to solve the nonlinear equation. Subsequently,a simulation model to reconstruct the B_(p) profile of STs is developed and the experimental setup of LITP is designed for EXL-50, a middle-sized ST. Simulation results of the reconstruction show that the relative errors of B_(p) reconstruction are mostly below 5%. Moreover, even with 5 mm measurement error on beam traces or 1 cm flux surface shape error, the average relative error of reconstruction remains below 15%, initially demonstrating the robustness of LITP in diagnosing B_(p) profiles in STs. 展开更多
关键词 laser-driven ion-beam trace probe poloidal magnetic field diagnostic iterative reconstruction
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Observation of double pseudowaves in an ion-beam-plasma system
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作者 Zi-An Wei Jin-Xiu Ma Kai-Yang Yi 《Chinese Physics B》 SCIE EI CAS CSCD 2018年第8期350-355,共6页
Pseudowaves, known as burst-ion signals, which are different from plasma normal modes, exist frequently in ion- wave excitation experiments when launching the waves by applying a pulsed voltage to a negatively biased ... Pseudowaves, known as burst-ion signals, which are different from plasma normal modes, exist frequently in ion- wave excitation experiments when launching the waves by applying a pulsed voltage to a negatively biased grid. In previous experiments, only one kind of the pseudowave was observed. In this paper, we report the observation and identification of double pseudowaves in an ion-beam-plasma system. These pseudowaves originate from two ion groups: the burst of the beam ions and the burst of the background ions. It was observed that the burst of the background ions was in the case of high ion beam energy, while the burst of the beam ions was in the case of low ion beam energy. By observing the dependence of the signal velocities on the characteristics of the excitation voltage, these pseudowaves can be identified. It was also observed that the burst ion signal originating from the background ions can interact with slow beam mode and that originating from the beam ions can interact with fast beam mode. 展开更多
关键词 ion-beam-plasma system normal modes pseudowaves wave-particle interaction
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Purification and Properties of a New L-Sorbose Dehydrogenase Accelerative Protein from Bacillus megaterium Bred by Ion-Beam Implantation 被引量:9
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作者 赵世光 姚黎明 +4 位作者 苏彩欣 王陶 王军 汤明礼 余增亮 《Plasma Science and Technology》 SCIE EI CAS CSCD 2008年第3期398-402,共5页
Bacillus megaterium BM302 bred by ion-beam implantation produces L-sorbose dehydrogenase accelerative protein (SAP) to accelerate the activity of L-sorbose dehydrogenase (SDH) of Gluconobacter oxydans in the 2-ket... Bacillus megaterium BM302 bred by ion-beam implantation produces L-sorbose dehydrogenase accelerative protein (SAP) to accelerate the activity of L-sorbose dehydrogenase (SDH) of Gluconobacter oxydans in the 2-keto-L-gulonic acid (2KLG) fermentation from L-sorbose by the mixed culture of B. megaterium BM302 and G. oxydans. The SAP purified by three chromatographic steps gave 35-fold purification with a yield of 13% and a specific activity of 5.21 units/mg protein. The molecular weight of the purified SAP was about 58 kDa. The SDH accelerative activity of SAP at pH 7 and 50℃ was the highest. Additionally, it retained 60% activity at a pH range of 6.5 ~ 10 and was stable at 20℃ ~ 60℃. After 0.32-unit SAP was added to the single cultured G. oxydans strains, the SDH activity was apparently accelerated and the 2KLG yield of GO29, GO112, GO and GI13 was enhanced 2.1, 3.3, 3.5 and 2.9 folds respectively over that of the strains without the addition of SAP. 展开更多
关键词 bacillus megaterium BM302 ion beam implantation counterpart protein two-step fermentation of Vc
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Control of Beam Energy and Flux Ratio in an Ion-Beam-Background Plasma System Produced in a Double Plasma Device
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作者 WEI Zian MAJinxiu +2 位作者 LI Yuanrui SUN Yan JIANG Zhengqi 《Plasma Science and Technology》 SCIE EI CAS CSCD 2016年第11期1076-1080,共5页
Plasmas containing ion beams have various applications both in plasma technology and in fundamental research. The ion beam energy and flux are the two factors characterizing the beam properties. Previous studies have ... Plasmas containing ion beams have various applications both in plasma technology and in fundamental research. The ion beam energy and flux are the two factors characterizing the beam properties. Previous studies have not achieved the independent adjustment of these two parameters. In this paper, an ion-beam-background-plasma system was produced with hotcathode discharge in a double plasma device separated by two adjacent grids, with which the beam energy and flux ratio (the ratio between the beam flux and total ion flux) can be controlled independently. It is shown that the discharge voltage (i.e., voltage across the hot-cathode and anode) and the voltage drop between the two separation grids can be used to effectively control the beam energy while the flux ratio is not affected by these voltages. The flux ratio depends sensitively on hot-filaments heating current whose influence on the beam energy is relatively weak, and thus enabling approximate control of the flux ratio 展开更多
关键词 ion beam background plasma beam energy flux ratio
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A New hcp Phase Formed in the Ni-Nb System during Ion-beam-assisted Deposition
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作者 Bin ZHAO, Kuiwei GENG, Fei ZENG and Feng PANLaboratory of Advanced Materials, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084, China 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2004年第5期577-579,共3页
The Ni80Nb20 films were prepared by ion beam assisted deposition (IBAD) with various Ar+ ion energies. A phase evolution of fcc→amorphous→Ni+Nb→Ni+hcp was observed with the increasing of ion beam energy from 2 keV ... The Ni80Nb20 films were prepared by ion beam assisted deposition (IBAD) with various Ar+ ion energies. A phase evolution of fcc→amorphous→Ni+Nb→Ni+hcp was observed with the increasing of ion beam energy from 2 keV to 8 keV. When bombarded by Ar+ ions of 8 keV during deposition, a new crystalline phase with hcp structure was obtained, of which the lattice parameters are a=0.286 nm and c=0.483 nm, different from those of the similar A3B-type hcp phase previously reported. The experimental results were discussed in terms of thermodynamics and restricted kinetic conditions in the far-from-equilibrium process of IBAD. The formation of hep phase may also be related to the valence electron effect. 展开更多
关键词 Hcp phase Ni-Nb Ion beam assisted deposition THERMODYNAMICS Valence electron effect
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Research on the Distant Hybrids of Wheat Obtained via Low-Energy Ion-Beam Implantation
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作者 苌收伟 程玉红 +1 位作者 秦广雍 苏明杰 《Plasma Science and Technology》 SCIE EI CAS CSCD 2003年第3期1821-1824,共4页
The whole DNA of soybean was implanted into four varieties of wheat of Zhongyu 5, Huaiyin 9628, Wenyou 1, Jimai 5 respectively via ion-beam mediation. There were 5 plants obtained whose protein content was higher than... The whole DNA of soybean was implanted into four varieties of wheat of Zhongyu 5, Huaiyin 9628, Wenyou 1, Jimai 5 respectively via ion-beam mediation. There were 5 plants obtained whose protein content was higher than 18.5 %, the highest one was 21.44 %. There were 3 plants obtained whose protein content was lower than 11.5%, the lowest one was 10.96%. We can see that the whole DNA of soybean transformed into wheat via ion beam implantation can induce the increase in wheat protein content dramatically. The result also shows that the transformation efficiency of different gene types of wheat receptor varies greatly that the implanting time has a certain effect on the efficiency of transformation. 展开更多
关键词 transformation via ion beam soy DNA distant hybrid
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The influence of sequence of precursor films on CZTSe thin films prepared by ion-beam sputtering deposition
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作者 Jun Zhao Guangxing Liang +4 位作者 Yang Zeng Ping Fan Juguang Hu Jingting Luo Dongping Zhang 《Journal of Semiconductors》 EI CAS CSCD 2017年第2期15-19,共5页
The CuZnSn(CZT) precursor thin films are grown by ion-beam sputtering Cu, Zn, Sn targets with different orders and then sputtering Se target to fabricate Cu_2ZnSnSe_4(CZTSe) absorber thin films on molybdenum subst... The CuZnSn(CZT) precursor thin films are grown by ion-beam sputtering Cu, Zn, Sn targets with different orders and then sputtering Se target to fabricate Cu_2ZnSnSe_4(CZTSe) absorber thin films on molybdenum substrates. They are annealed in the same vacuum chamber at 400 ℃. The characterization methods of CZTSe thin films include X-ray diffraction(XRD), energy dispersive spectroscopy(EDS), scanning electron microscopy(SEM), and X-ray photoelectron spectra(XPS) in order to study the crystallographic properties, composition, surface morphology, electrical properties and so on. The results display that the CZTSe thin films got the strongest diffraction peak intensity and were with good crystalline quality and its morphology appeared smooth and compact with a sequence of Cu/Zn/Sn/Se, which reveals that the expected states for CZTSe are Cu^(1+), Zn^(2+), Sn^(4+), Se^(2).With the good crystalline quality and close to ideal stoichiometric ratio the resistivity of the CZTSe film with the sequence of Cu/Zn/Sn/Se is lower, whose optical band gap is about 1.50 eV. 展开更多
关键词 CZTSe thin films ion-beam sputtering chalcogenide
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Fabrication and efficiency measurement of a multilayer-coated ion-beam-etched laminar grating for extreme ultraviolet region 被引量:4
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作者 林慧 张立超 +2 位作者 金春水 周洪军 霍同林 《Chinese Optics Letters》 SCIE EI CAS CSCD 2009年第3期180-182,共3页
We fabricate and measure a multilayer-coated ion-beam-etched laminar grating for the extreme ultraviolet wavelength region. The fabrication process is carefully controlled so that the grating groove and multilayercoat... We fabricate and measure a multilayer-coated ion-beam-etched laminar grating for the extreme ultraviolet wavelength region. The fabrication process is carefully controlled so that the grating groove and multilayercoating parameters well meet the design targets. At an incident angle of 10°, the peak diffraction efficiency of the +1st order is 20.6% at 14.56 nm and that of the -1st order is 22.1% at 14.65 nm, both close to the theoretical limits. 展开更多
关键词 Ion beams Laser pulses MULTILAYERS
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In-situ end-point detection during ion-beam etching of multilayer dielectric gratings 被引量:1
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作者 林华 李立峰 曾理江 《Chinese Optics Letters》 SCIE EI CAS CSCD 2005年第2期63-65,共3页
An in-situ end-point detection technique for ion-beam etching is presented. A laser beam of the same wavelength and polarization as those in the intended application of the grating is fed into the vacuum chamber, and ... An in-situ end-point detection technique for ion-beam etching is presented. A laser beam of the same wavelength and polarization as those in the intended application of the grating is fed into the vacuum chamber, and the beam retro-diffracted by the grating under etching is extracted and detected outside the chamber. This arrangement greatly simplifies the end-point detection. Modeling the grating diffraction with a rigorous diffraction grating computer program, we can satisfactorily simulate the evolution of the diffraction intensity during the etching process and consequently, we can accurately predict the end-point. Employing the proposed technique, we have reproducibly fabricated multilayer dielectric gratings with diffraction efficiencies of more than 92%. 展开更多
关键词 Computer programming Dielectric materials ETCHING Ion beams Laser beams Mathematical models VACUUM
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Investigation on the properties of high reflective mirror prepared by ion-beam sputtering
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作者 黄建兵 田光磊 +1 位作者 邵建达 范正修 《Chinese Optics Letters》 SCIE EI CAS CSCD 2005年第11期676-678,共3页
The single-sided and dual-sided high reflective mirrors were deposited with ion-beam sputtering (IBS). When the incident light entered with 45°, the reflectance of p-polarized light at 1064 nm exceeded 99.5%. S... The single-sided and dual-sided high reflective mirrors were deposited with ion-beam sputtering (IBS). When the incident light entered with 45°, the reflectance of p-polarized light at 1064 nm exceeded 99.5%. Spectrum was gained by spectrometer and weak absorption of coatings was measured by surface thermal lensing (STL) technique. Laser-induced damage threshold (LIDT) was determined and the damage morphology was observed with Lecia-DMRXE microscope simultaneously. The profile of coatings was measured with Mark III-GPI digital interferometer. It was found that the reflectivity of mirror exceeded 99.9% and its absorption was as low as 14 ppm. The reflective bandwidth of the dual-sided sample was about 43 nm wider than that of single-sided sample, and its LIDT was as high as 28 J/cm^2, which was 5 J/cm^2 higher than that of single-sided sample. Moreover, the profile of dual-sided sample was better than that of substrate without coatings. 展开更多
关键词 Coatings INTERFEROMETERS Ion beams Laser damage Light polarization MICROSCOPES Reflection SPUTTERING
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离子束加工镍单晶原子级去除行为与表面损伤机制研究
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作者 李晓静 王泽骜 +2 位作者 秦胜建 高永亮 王林 《表面技术》 北大核心 2025年第22期129-140,共12页
目的模拟氩(Ar)离子束溅射单晶镍(Ni)的行为,分析其原子级结构演变规律,揭示金属Ni的去除机制及表面与亚表面损伤机制。方法采用分子动力学(MD)方法,模拟不同溅射能量(600 eV、1000 eV和1400 eV)、剂量(1.5625×10^(13)ions/cm^(2)... 目的模拟氩(Ar)离子束溅射单晶镍(Ni)的行为,分析其原子级结构演变规律,揭示金属Ni的去除机制及表面与亚表面损伤机制。方法采用分子动力学(MD)方法,模拟不同溅射能量(600 eV、1000 eV和1400 eV)、剂量(1.5625×10^(13)ions/cm^(2)和3.1250×10^(13)ions/cm^(2))及入射角度(30°、45°、60°、75°和90°)下,Ar离子束溅射单晶金属Ni(001)表面过程。基于原子级微结构表征,系统分析溅射能量、剂量及角度对Ni(001)表面损伤形貌、应变分布以及溅射产额的影响规律,阐明其表面损伤机制和原子去除机制。结果Ar离子束溅射在Ni(001)面溅射核心区域形成凹坑与表面原子堆积,并在亚表面诱发非晶原子团簇及{111}面层错等损伤结构;伴随结构缺陷的产生,核心溅射区域产生应变集中。凹坑面积、表面堆积原子数、非晶团簇原子比例、层错原子比例、亚表面损伤深度和应变均随溅射能量和剂量的增加而增大;其中60°入射角下产生的表面及亚表面损伤最为显著。溅射产额亦随溅射能量和剂量的增加而升高;30°入射角下因独特的“铲削效应”,溅射产额达到最高;应变集中和层错在后续温度平衡过程中逐渐消失。结论离子束加工条件(能量、剂量、角度)对单晶Ni表面及亚表面损伤具有显著影响。损伤程度随溅射能量和离子剂量的增加而加剧;60°入射角时损伤最显著,而30°入射角下原子去除效率最高。本研究为实验优化离子束加工工艺提供了理论依据。 展开更多
关键词 离子束加工 单晶 表面损伤 溅射产额 分子动力学
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负氦离子束产生技术研究
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作者 陈浩南 崔保群 +9 位作者 唐兵 陈立华 马瑞刚 马鹰俊 马燮 张一帆 赵建革 王云峰 杨超 于荣凯 《原子能科学技术》 北大核心 2025年第1期205-212,共8页
串列加速器可产生MeV级的正离子束,其中He离子束可用于离子束分析、离子注入等实验研究和工业应用,是串列加速器不可或缺的一种离子束流。串列加速器要求负离子注入,负氦离子束是串列加速器产生MeV级He离子束的关键。由于基态He原子电... 串列加速器可产生MeV级的正离子束,其中He离子束可用于离子束分析、离子注入等实验研究和工业应用,是串列加速器不可或缺的一种离子束流。串列加速器要求负离子注入,负氦离子束是串列加速器产生MeV级He离子束的关键。由于基态He原子电子亲合能小于0,无法直接在离子源中产生和引出He-离子束,只能通过连续两次的电荷交换产生,所以He^(-)离子束被认为是最难产生的负离子束之一。针对串列加速器He^(-)离子的注入需求,研究设计了一款负氦离子源,使用多峰会切场离子源电离产生He^(+)离子,注入电荷交换器中,通过电荷交换产生He^(-)离子束。模拟了多峰会切场离子源的磁场位形和粒子轨迹,验证了多峰场构型对电子约束的作用,能维持离子源稳定放电。设计了电荷交换器结构,考虑了热平衡状态时的温度分布,确保了金属Cs作为电荷交换介质的长期稳定运行。基于中国原子能科学研究院1.7 MV串列加速器低能束流线平台开展了产生负氦离子束的实验,优化了离子束的聚焦传输参数,测量了电荷交换器工作温度和He^(+)离子注入能量对He^(-)离子产率的影响。实验中测得最大He^(-)离子产率为1.76%±0.03%,调节离子源放电参数得到了最大1.5μA的He^(-)离子束流,基本满足串列加速器的注入需求。后续进一步改进离子源,增强放电强度,提高引出He^(+)离子流强,有望进一步提升He^(-)离子流强。该研究为国产负氦离子源的发展提供了重要技术支持,对实现串列加速器技术的自主可控具有重要意义。 展开更多
关键词 负氦离子束 离子源 电荷交换 负氦离子产率
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激光加速低能碳离子束在CHO泡沫中的电荷转移过程
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作者 程渝 任洁茹 +12 位作者 马步博 刘云 赵子乾 魏文青 Dieter H.H.Hoffmann 邓志刚 齐伟 周维民 程锐 李忠良 宋磊 李源 赵永涛 《物理学报》 北大核心 2025年第15期135-142,共8页
离子与物质相互作用中的电荷转移过程研究对于离子束驱动高能量密度物理、材料离子辐照损伤、离子束电荷剥离技术等领域至关重要.本文利用激光驱动靶背鞘层场加速机制产生了能量在数MeV量级的碳离子束,测量了碳离子束穿过具有孔状结构的... 离子与物质相互作用中的电荷转移过程研究对于离子束驱动高能量密度物理、材料离子辐照损伤、离子束电荷剥离技术等领域至关重要.本文利用激光驱动靶背鞘层场加速机制产生了能量在数MeV量级的碳离子束,测量了碳离子束穿过具有孔状结构的C_(9)H_(16)O_(8)泡沫靶后的电荷态分布.实验结果与理论对比发现,只有同时考虑了电离、俘获、激发和退激等过程的速率方程结果与实验符合很好.采用气体靶截面数据求解速率方程获得的平衡电荷态低估了实验值,原因在于泡沫结构靶中固态纤维丝引起的靶密度效应导致离子电荷态升高.当离子能量高于3 MeV以上时,实验值与采用了固态靶截面数据的速率方程理论预期一致;但在低能区出现明显偏差,原因在于当入射能量小于3 MeV时,离子激发态寿命小于碰撞时间尺度,激发态电子在发生第二次碰撞之前退激发回到基态,靶密度效应减弱,平均电荷态降低,实验结果与详细考虑了激发和退激过程的ETACHA程序预期吻合.该工作为理解离子束与物质相互作用微观机制以及电荷转移模型检验提供了数据和参考. 展开更多
关键词 激光加速 碳离子束 电荷交换 靶密度效应
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基于M1TDS靶向筛选技术的重离子束诱变定向改良杂交水稻卓两优1126性状的研究
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作者 韶也 胡远艺 +16 位作者 彭彦 毛毕刚 刘慧敏 唐婵娟 雷斌 唐丽 余丽霞 李文建 罗武中 罗治斌 袁远涛 李曜魁 张丹 周利斌 柏连阳 唐文帮 赵炳然 《中国水稻科学》 北大核心 2025年第5期624-634,共11页
【目的】以两系杂交水稻卓两优1126为“底盘品种”,快速创制具有镉低积累、香味、耐储藏、耐淹、低升糖指数等性状的改良品种。【方法】12C6+碳离子束诱变卓两优1126亲本卓234S和湘农恢1126,利用M1TDS技术从诱变M1群体中鉴定OsNRAMP5、O... 【目的】以两系杂交水稻卓两优1126为“底盘品种”,快速创制具有镉低积累、香味、耐储藏、耐淹、低升糖指数等性状的改良品种。【方法】12C6+碳离子束诱变卓两优1126亲本卓234S和湘农恢1126,利用M1TDS技术从诱变M1群体中鉴定OsNRAMP5、OsBADH2、OsLOX3、OsPAO5、OsSSIIIa和OsBEIIb基因嵌合突变株,通过KASP分型从诱变M2群体中鉴定分离目标基因纯合(杂合)突变株,利用OsNRAMP5突变亲本配制OsNRAMP5突变组合。【结果】从重离子束诱变M1群体中鉴定到13株为5个目标基因突变的嵌合突变株,其中7个M2株系中鉴定到目标基因的纯合或杂合突变;OsNRAMP5纯合突变株镉含量较原始亲本显著降低,OsBADH2纯合突变株香味特征化合物2-乙酰基吡咯啉(2-AP)含量较原始亲本显著上升;OsNRAMP5基因突变亲本配制的组合,在镉污染土(土壤有效镉含量0.677 mg/kg,pH 5.6)盆栽种植,其籽粒镉含量为0.05 mg/kg,而原始组合为0.91 mg/kg。【结论】利用“重离子束诱变+M1TDS技术”实现了卓两优1126镉低积累等性状的快速改良,为生物传统诱变育种进化到定向诱变育种提拱了成功案例和共性技术参考。 展开更多
关键词 水稻 重离子束诱变育种 镉低积累 香味
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