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国际上最早使用的微型探测器是盖革-缪勒计数器,并用它首次对活体内的肿瘤进行了测试。六十年代以来,它逐步为半导体探测器所代替。七十年代以来,微型半导体探测器已广泛地用于血流动力学、肺功能研究以及食管、胃和眼睛等体内和体表器官的诊断。我们也曾用半导体硅探测器对甲状腺节结进行过测试,效果良好。  相似文献   

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离子注入技术在植物育种中的应用与研究进展   总被引:1,自引:0,他引:1  
离子束作为一种新的诱变源,具有突变谱广、突变率高、生理损伤小的特点,并且具有一定的重复性和方向性。文章阐述了离子注入的特点、诱变机理和诱变效应,综述了诱变育种取得的进展,展望了离子注入技术的应用前景。  相似文献   

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本文介绍了正研制的氢氦离子注入机的结构和各部分的主要性能指标。它的最高能量为200 keV,可按一定比例同时用氢氦两种离子进行注入实验。该机经调试,各项主要指标已达设计要求,工作稳定可靠。  相似文献   

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全方位离子注入与沉积技术及其工业机的研制   总被引:3,自引:0,他引:3  
王浪平  王小峰  汤宝寅 《核技术》2007,30(12):983-986
全方位离子注入与沉积(Plasma immersion ion implantation and deposition,PIIID)技术发展到现在,已经逐步走向工业化应用。本文介绍了全方位离子注入与沉积技术的原理,探讨了全方位离子注入与沉积工业机应该具备的功能,介绍了研制成功的全方位离子注入与沉积设备的结构和实施效果,其脉冲阴极弧等离子体源沉积速率达到2.9A/s,IGBT固体开关调制器输出电压达到10kv,能够一次处理多个工业零件。  相似文献   

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本文介绍了液态铀离子选择电极的制备及其功能。讨论了载体的孔隙度、载体长度、活性溶液中交换剂浓度和苯甲酸浓度等与电极功能的关系。电极斜率分别为56.4±2mV(活性溶液铀浓度5×10~(-4)M)和52±1mV(活性溶液铀浓度1×10~(-4)M),在2×10~(-6)-1×10~(-4)M铀浓度范围内呈线性关系。该电极具有灵敏、响应迅速、温度效应小、选择性好和使用寿命长等优点。用于矿水及工艺液流中微量铀的测定,获得了较满意的结果。  相似文献   

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用沟道离子注入法生成的稀土硅化物经背散射沟道分析,电镜分析和X射线衍射测试表明,它具有很好的结晶品质和很高的相稳定性。  相似文献   

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能量为几十千到几百千电子伏离子射入材料表面,使表面层的组成与结构发生改变,从而引起材料表面的物理与化学性质的变化,这种材料改性方法有极其重要的应用。如摩擦、润滑性、耐磨损性、表面硬化、抗高温氧化性、耐腐蚀性、催化及附着力改善等。虽然离子注入可改善材料这些性质,但由于经济与技术上的原因,最重要的研究集中在耐磨损性、抗高温氧化性及某些耐蚀性上,而耐磨性的研究以工具上的应用为最多。  相似文献   

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谢利平  康明杰  堵敏轩  杜毅 《核技术》2007,30(4):394-396
采用离子注入技术研制的便携式半导体核辐射仪,其各项技术指标均有很大的改进和提高,达到了国内先进水平,可广泛用于空间和环境中X射线和γ射线的探测领域.  相似文献   

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离子注入Q薄膜的电导性及XPS研究   总被引:1,自引:0,他引:1  
王培录  冯克鲁 《核技术》1990,13(6):350-354
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O、C离子注入n型GaN的黄光发射研究   总被引:1,自引:1,他引:0  
采用光致发光(Photoluminescencc,PL)谱的测量,研究了1012~1017cm-2的O和C两种离子注入和退火对非有意掺杂的n型GaN黄光发射(Yellow luminescence,YL)的影响,注入后的样品在流动N2的保护下进行退火,退火温度950℃,退火时间30 min.对比相同剂量下N离子注入GaN黄光发射,结果表明O、C两种离子的注入在GaN中分别引入了与黄光发射相关的不同的深能级中心,当C离子注入剂量高达1017cm-2时,能引起黄光发射的C相关的深能级中心显著增多.  相似文献   

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We present a method of ion implantation doping of GaN, which permits reduced residual damage. The method consists of performing implantation in several steps with annealing between each step. Residual damage was analyzed by RBS/channeling and compared to a traditional implantation and annealing procedure. Better lattice recovery is clearly achieved using the alternating implantation and annealing approach. We attribute the efficient recovery to smaller damage amounts introduced during each implantation step, as well as to suppression of secondary defect formation.  相似文献   

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为加热HT-6M托卡马克等离子体而研制的IS-A十厘米双潘宁离子源具有强流、大功率、高质子比等特点。经过进一步的发展,该源可以引出多种气体离子束,以满足不同实验的需要。本文详细地研究了几何结构和运行条件对源等离子体的影响。报道了该离子源在其它领域中的初步应用。  相似文献   

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In this study we compare and discuss the defects and optical behaviour of sapphire and magnesium oxide single crystals implanted at room temperature with different fluences (1 × 1015-1 × 1016 cm−2) of europium ions.Rutherford backscattering channelling shows that for fluences above 5 × 1015 cm−2 the surface disorder level in the Al-sublattice reaches the random level. Implantation damage recovers fast for annealing in oxidizing atmosphere but even for the highest fluence we recover almost completely all the damage after annealing at 1300 °C, independently of the annealing environment (reducing or oxidizing). Annealing above 1000 °C promotes the formation of Eu2O3 in the samples with higher concentration of Eu. The optical activation of the rare earth ions at room temperature was observed after annealing at 800 °C by photoluminescence and ionoluminescence. In Al2O3 lattice the highest intensity line of the Eu3+ ions corresponds to the forced electric dipole 5D0 → 7F2 transition that occurs ∼616 nm. For the MgO samples the Eu3+ optical activation was also achieved after implantation with different fluences. Here, the lanthanide recombination is dominated by the magnetic dipole 5D0 → 7F1 transition near by 590 nm commonly observed for samples were Eu3+ is placed in a high symmetry local site. The results clearly demonstrate the possibility to get Eu incorporated in optical active regular lattice sites in wide gap oxides.  相似文献   

17.
樊东辉  李世普 《核技术》1995,18(3):154-157
用X射线衍射法和POWD12理论计算程序探讨了多晶刚玉Fe离子注入层的结构变化。  相似文献   

18.
曾宇昕  程国安  王水凤  肖志松 《核技术》2003,26(11):823-826
采用金属蒸气真空弧(MEWA)离子源以低束流方式将Nd离子注入到外延硅片中,经高温快速退火处理,制备了结晶良好的钕硅掺杂层。用扫描电子显微镜(SEM)、反射式高能电子衍射(RHEED)和X射线衍射(XRD)分析了在不同退火条件下样品注入层相结构的变化。研究结果表明,经高温热处理,注入层形成结晶良好的钕硅化合物,出现由Nd5Si4相向NdSi相转变的趋势。并对其转变过程进行了初步探讨。  相似文献   

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Sapphire single crystals were implanted at room temperature with 180 keV manganese ions to fluences up to 1.8 × 1017 cm−2. The samples were annealed at 1000 °C in oxidizing or reducing atmosphere. Surface damage was observed after implantation of low fluences, the amorphous phase being observed after implantation of 5 × 1016 cm−2, as seen by Rutherford backscattering spectroscopy under channelling conditions. Thermal treatments in air annealed most of the implantation related defects and promoted the redistribution of the manganese ions, in a mixed oxide phase. X-ray diffraction studies revealed the presence of MnAl2O4. On the contrary, similar heat treatments in vacuum led to enhanced out diffusion of Mn while the matrix remained highly damaged. The analysis of laser induced luminescence performed after implantation showed the presence of an intense red emission.  相似文献   

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Room temperature ferromagnetic ordering has been observed in ZnO by implanting 1.63 MeV 56Fe6+ ions. The total number of implanted Fe ions in ZnO is 1 × 1016, which is effectively 1 at.% doping of Fe in ZnO. The amount of saturation magnetic moment in Fe implanted ZnO, annealed to 500 °C, has been found to be two orders of magnitude more than that observed earlier in chemically prepared Zn0.98Mn0.02O and Zn0.96Mn0.02Fe0.02O samples.  相似文献   

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