Institutional Repository of Institute of Modern Physics, CAS
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HIGH INTENSITY CYCLOTRONS FOR SUPER HEAVY ELEMENTS
No full textMain theme of FLNR JINR is super heavy elements<br />research. From 2000 up to 2010 more then 40 isotopes<br />of elements 112, 113, 114, 115, 116, 117, 118 were<br />synthesized in the laboratory. As a target we used<br />243Am, 242Pu, 248Cm, 249Bk, 249Cf et al. Total flux<br />48Ca ion beam was on the level 5·1020 ion. 48Ca<br />matter consumption in ion source averaged 0.4<br />mg/hour at the beam intensity of 1 pμA .<br />According plan after U-400 cyclotron modernization<br />(2012) 48Ca beam intensity will be increased up to<br />3pμA on the target and 48Ca. New cyclotron DC-200<br />planed to be put in to operation in 2014 will allow to<br />reach 10 pμA of 48 Ca beam intensity
Mass Measurements of Proton-rich Nuclides at the Cooler Storage Ring at IMP
No full textRecent results and progress of mass measurements of proton-rich nuclei using isochronous mass spectrometry (IMS) are reported. The nuclei under investigation were produced via fragmentation of relativistic energy heavy ions of Kr-78 and Ni-58. After in-flight separation by the fragment separator RIBLL-2, the nuclei were injected and stored in the experimental storage ring CSRe, and their masses were determined from measurements of the revolution times. The impact of these measurements on the stellar nucleosynthesis in the rp-process is discussed
Precipitates and defects in silicon co-implanted with helium and oxygen
No full textNano-bubbles or voids introduced by He implantation before the oxygen implantation collect oxygen and increase the oxygen content in the sample. Furthermore, nano-bubbles or voids can trap Si interstitials to decrease the dislocations at the edge of precipitates. The density and shape of precipitates formed in the initial stage of the separation-by-implanted-oxygen process are related to the size and density of He-induced vacancy-type defects (nano-bubbles and voids). A high density of nano-bubbles is more efficient in gettering than that of a low density of voids. (C) 2011 Elsevier B.V. All rights reserved
Potential energy threshold of surface erosion on GaN by impact of slow highly charged heavy ions
No full textIn the present work the erosion behavior on the surface of GaN epi-layer by the impact of various slow highly charged heavy ions (SHCIs, including Arq+. Xeq+ and Pbq+, in two incidence geometries) was investigated. Atomic force microscopy reveals a well-defined threshold of potential energy carried by the incident heavy ions accounting for the surface erosion. This threshold also depends on the projected range of the SHCIs, the longer the projected range, the higher the potential energy required for the onset of surface erosion. And the etched depth is close to a linear function of potential energy deposited, increasing with the potential energy increases. Moreover, the etching rate for 60 degrees off normal incidence is by more than a factor of 2 larger than etching rate for normal incidence, and the etch rate by Xeq+ is larger than by Pbq+ under the same potential energy and incident direction. And a mechanism is discussed. (C) 2010 Elsevier B.V. All rights reserved
大型高频谐振腔体内导电杆的制造方法
No full text本发明主要涉及一种大型高频谐振腔体内导电杆的制造方法，其通过：在平台上将无氧铜半管与半方盒焊为一体；锡焊半管和半方盒内壁上的冷却盘管；焊接管套与封头并检漏；用夹环夹紧两半管和半方盒的焊合件，并将封头和管套焊合件套在上述拼合件的端头；用真空电子束焊点焊上述拼合件为一体，拆掉夹环，二次利用真空电子束焊，将两半管之间和两半管与封头之间拼缝焊透；在水冷下焊接两半盒和半盒与漂移管之间的拼接缝；焊接冷却盘管与管套间的拼接缝并检漏；精加工内导电杆；最后对外表面机械抛光。采用此新工艺制造出的大型高频谐振腔体内导电杆，表面电阻小、导电性能好、冷却效率高、稳定性佳、外形尺寸及形状误差小、真空指标好，改善和提高了整个高频谐振腔体性能
Direct Mass Measurements of Short-Lived A=2Z-1 Nuclides Ge-63, As-65, Se-67, and Kr-71 and Their Impact on Nucleosynthesis in the rp Process
No full textMass excesses of short-lived A = 2Z - 1 nuclei Ge-63, As-65, Se-67, and Kr-71 have been directly measured to be -46 921(37), -46 937(85), -46 580(67), and -46 320(141) keV, respectively. The deduced proton separation energy of -90(85) keV for As-65 shows that this nucleus is only slightly proton unbound. X-ray burst model calculations with the new mass excess of As-65 suggest that the majority of the reaction flow passes through Ge-64 via proton capture, indicating that Ge-64 is not a significant rp-process waiting point
电荷频率转换器
No full text本发明是测量电荷(电流)信号并将其转换成频率输出的前端测量电路。一种电荷频率转换器，其主要特点在于：电流信号输入端P1通过电阻R2与积分电路(1)的输入端连接；积分电路(1)的输出端通过幅度鉴别电路(2) 与窄脉冲成形电路(3)的输入端相连接；窄脉冲成形电路(3)的输出1端分别与延时电路(4)的输入端、输出脉冲整形电路(6)的输入端和第一泄放开关(8)的控制端相连接；延时电路(4)的输出端通过幅度控制与耦合电路(5)与泄放支路相连接；窄脉冲成形电路(3)的输出2端与第二泄放开关(9)的控制端相连接；输出脉冲整形电路(6)的输出端与频率输出级电路(7)相连接。本发明为束流强度检测探测器的信号读出提供了一种结构简单、性能可靠的测量电路
甜高粱汁液的生物贮存方法
No full text本发明提供了一种甜高粱汁液的生物贮存方法，是将新压榨的甜高粱汁液送入密闭贮罐，调整pH值至4.5～6.5，泵入灭菌罐，于温度60～90℃下蒸汽灭菌30～60分钟；然后冷却至10～25℃，除去沉淀，加入汁液质量0.01％～0.1％的酶搅拌均匀，立即泵入带有单向呼吸阀的密闭贮罐贮存。本发明利用微生物低温生长缓慢、向单一方向代谢的过程，竞争性抑制其它微生物的生长繁殖，从而达到保护汁液不变质的目的。实验证明，甜高粱汁液通过本发明生物贮存，三个月不变质
