期刊文献+
共找到16篇文章
< 1 >
每页显示 20 50 100
Effects of Space Radiation Mutation on Germination and Growth of Sugarcane Hybrid Seeds 被引量:3
1
作者 Yimei GAN Yuanli WU +4 位作者 Jun ZENG Wenwei CAI Zhengying CAO Lishun PENG Benpeng YANG 《Agricultural Biotechnology》 CAS 2019年第6期15-18,共4页
[Objectives] This study was conducted to investigate the mutagenic effects of space radiation mutagenesis on sugarcane hybrid seeds. [Methods] Sugarcane hybrid spikes were subjected to space radiation mutagenesis trea... [Objectives] This study was conducted to investigate the mutagenic effects of space radiation mutagenesis on sugarcane hybrid seeds. [Methods] Sugarcane hybrid spikes were subjected to space radiation mutagenesis treatment to identify the effects on the germination, seedling growth and plant growth and development of sugarcane hybrid seeds. [Results] The space radiation treatment had a great impact on the germination and growth of sugarcane hybrid seeds, especially on the germination of sugarcane seeds. The germination number per gram of seeds increased significantly, and the survival rate of seedlings increased significantly. The effect on the growth status was relatively small. The average number of tillers decreased slightly, the percentage of available stems increased, and the plants became higher, which resulted in a greater effect on sugarcane yield. Sugarcane sucrose was increased. The seed germination and late growth status indicated that space radiation promoted the germination and growth of sugarcane hybrid seeds. [Conclusions] This study provides a basis for the space radiation mutagenesis breeding of sugarcane hybrid seeds and the promotion of sugarcane breeding process. 展开更多
关键词 space radiation SUGARCANE Mutation breeding Seed germination
下载PDF
Space radiation effect on fibre optical gyroscope control circuit and compensation algorithm 被引量:1
2
作者 张春熹 田海亭 +2 位作者 李敏 金靖 宋凝芳 《Chinese Physics B》 SCIE EI CAS CSCD 2008年第2期573-577,共5页
The process of a γ-irradiation experiment of fibre optical gyroscope (FOG) control circuit was described, in which it is demonstrated that the FOG control circuit, except for D/A converter, could endure the dose of... The process of a γ-irradiation experiment of fibre optical gyroscope (FOG) control circuit was described, in which it is demonstrated that the FOG control circuit, except for D/A converter, could endure the dose of 10krad with the protection of cabin material. The distortion and drift in D/A converter due to radiation, which affect the performance of FOG seriously, was indicated based on the elemental analysis. Finally, a compensation network based on adaptive neuro-fuzzy inference system is proposed and its function is verified by simulation. 展开更多
关键词 space radiation fibre optical gyroscope compensation network
下载PDF
Monte Carlo calculation of the exposure of Chinese female astronauts to earth’s trapped radiation on board the Chinese Space Station
3
作者 郭义盼 闫发智 +3 位作者 方美华 张昭 成巍 郭兵 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期631-638,共8页
With the development of China’s crewed space mission,the space radiation risk for astronauts is increasingly prominent.This paper describes a simulation of the radiation doses experienced by a Chinese female voxel ph... With the development of China’s crewed space mission,the space radiation risk for astronauts is increasingly prominent.This paper describes a simulation of the radiation doses experienced by a Chinese female voxel phantom on board the Chinese Space Station(CSS)performed using the Monte Carlo N-Particle(MCNP)software.The absorbed dose,equivalent dose,and effective dose experienced by the voxel phantom and its critical organs are discussed for different levels of shielding of the Tianhe core module.The risk of space-radiation exposure is then assessed by comparing these doses with the current risk limits in China(the skin dose limit for short-term low-earth-orbit missions)and the NASA figures(National Council on Radiation Protection and Measurements Report No.98)for female astronauts.The results obtained can be used to guide and optimize the radiation protection provided for manned space missions. 展开更多
关键词 space radiation Chinese female voxel phantom China’s space Station radiation exposure risk
下载PDF
Study of magnetic field expansion using a plasma generator for space radiation active protection 被引量:2
4
作者 贾向红 贾少霞 +6 位作者 许峰 白延强 万军 刘洪涛 蒋睿 马洪波 王守国 《Chinese Physics C》 SCIE CAS CSCD 2013年第9期99-103,共5页
There are many active protecting methods including Electrostatic Fields, Confined Magnetic Field, Unconfined Magnetic Field and Plasma Shielding etc. for defending the high-energy solar particle events (SPE) and Gal... There are many active protecting methods including Electrostatic Fields, Confined Magnetic Field, Unconfined Magnetic Field and Plasma Shielding etc. for defending the high-energy solar particle events (SPE) and Galactic Cosmic Rays (GCR) in deep space exploration. The concept of using cold plasma to expand a magnetic field is the best one of all possible methods so far. The magnetic field expansion caused by plasma can improve its protective efficiency of space particles. One kind of plasma generator has been developed and installed into the cylindrical permanent magnet in the eccentric. A plasma stream is produced using a helical-shaped antenna driven by a radio-frequency (RF) power supply of 13.56 MHz, which exits from both sides of the magnet and makes the magnetic field expand on one side. The discharging belts phenomenon is similar to the Earth's radiation belt, but the mechanism has yet to be understood. A magnetic probe is used to measure the magnetic field expansion distributions, and the results indicate that the magnetic field intensity increases under higher increments of the discharge power. 展开更多
关键词 plasma stream magnetic field expansion space radiation active protection
原文传递
Physical design and Monte Carlo simulations of a space radiation detector onboard the SJ-10 satellite
5
作者 刘雅清 王焕玉 +13 位作者 崔兴柱 彭文溪 樊瑞睿 梁晓华 高旻 张云龙 张承模 张家宇 杨家卫 汪锦州 张飞 董亦凡 郭东亚 周大卫 《Chinese Physics C》 SCIE CAS CSCD 2015年第1期54-59,共6页
A radiation gene box (RGB) onboard the S J-10 satellite is a device carrying mice and drosophila cells to determine the biological effects of space radiation environment. The shielded fluxes of different radioactive... A radiation gene box (RGB) onboard the S J-10 satellite is a device carrying mice and drosophila cells to determine the biological effects of space radiation environment. The shielded fluxes of different radioactive sources were calculated and the linear energy transfers of γ-rays, electrons, protons and α-particles in the tissue were acquired using A-150 tissue-equivalent plastic. Then, a conceptutual model of a space radiation instrument employing three semiconductor sub-detectors for deriving the charged and uncharged radiation environment of the RGB was designed. The energy depositions in the three sub-detectors were classified into 15 channels (bins) in an algorithm derived from the Monte Carlo method. The physical feasibility of the conceptual instrument was also verified by Monte Carlo simulations. 展开更多
关键词 particle detecting space radiation detector design Monte Carlo simulations
原文传递
NASA's Space Radiation Laboratory
6
作者 Shelley Canright 陈功 《当代外语研究》 2004年第11期20-22,共3页
太空船上的宇航员在太空飞行遨游时会受到太空射线的辐射,太空射线对人体的危害要比一般射线严重。它轻则损坏人体细胞,重则导致癌症。为了保护宇航员的安全,美国国家宇航局斥资3400万美元建造了一个太空射线实验室,模拟质子和离子的放... 太空船上的宇航员在太空飞行遨游时会受到太空射线的辐射,太空射线对人体的危害要比一般射线严重。它轻则损坏人体细胞,重则导致癌症。为了保护宇航员的安全,美国国家宇航局斥资3400万美元建造了一个太空射线实验室,模拟质子和离子的放射过程,本文介绍了其研究方法和目前已取得的进展。 展开更多
关键词 NASA’s space radiation Laboratory 宇航员
原文传递
The CCD instrument background of the SMILE SXI 被引量:2
7
作者 M.W.J.Hubbard O.Hetherington +6 位作者 D.J.Hall T.W.Buggey S.Parsons T.Arnold A.Holland C.Pagani S.Sembay 《Earth and Planetary Physics》 EI CSCD 2024年第1期15-24,共10页
The ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation environments.The Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrou... The ESA and CAS SMILE mission orbit is highly elliptical and will pass through multiple radiation environments.The Soft X-ray Imager(SXI)instrument aboard has a radiation shutter door designed to close when the surrounding radiation flux is high.The shutter door will close when passing below an altitude threshold to protect against trapped particles in the Earth’s Van Allen Belts.Therefore,two radiation environments can be approximated based on the shutter door position:open and closed.The instrument background for the CCDs(Charge-Coupled Devices)that form the focal plane array of the SXI were evaluated for the two environments.Due to the correlation of the space environment with the solar cycle,the solar minima and maxima,the background was also evaluated at these two extremes.The results demonstrated that the highest instrument background will occur during solar minima due to the main contributing source being Galactic Cosmic Rays(GCRs).It was also found that the open background was highest for solar minima and that the closed background was highest during solar maxima.This is due to the radiation shutter door acting as a scattering centre and the changes in the energy flux distribution of the GCRs between the two solar extremes. 展开更多
关键词 instrument background X-ray astronomy space radiation
下载PDF
Effect of radiation-induced mean wavelength shift in optical fibers on the scale factor of an interferometric fiber optic gyroscope at a wavelength of 1300 nm 被引量:7
8
作者 金靖 王学勤 +1 位作者 林松 宋凝芳 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第9期366-372,共7页
In order to analyze the effect of wavelength-dependent radiation-induced attenuation (RIA) on the mean trans- mission wavelength in optical fiber and the scale factor of interferometric fiber optic gyroscopes (IFOG... In order to analyze the effect of wavelength-dependent radiation-induced attenuation (RIA) on the mean trans- mission wavelength in optical fiber and the scale factor of interferometric fiber optic gyroscopes (IFOGs), three types of polarization-maintaining (PM) fibers are tested by using a 60Co γ-radiation source. The observed different mean wave- length shift (MWS) behaviors for different fibers are interpreted by color-center theory involving dose rate-dependent absorption bands in ultraviolet and visible ranges and total dose-dependent near-infrared absorption bands. To evaluate the mean wavelength variation in a fiber coil and the induced scale factor change for space-borne IFOGs under low radiation doses in a space environment, the influence of dose rate on the mean wavelength is investigated by testing four germanium (Ge) doped fibers and two germanium-phosphorus (Ge-P) codoped fibers irradiated at different dose rates. Experimental results indicate that the Ge-doped fibers show the least mean wavelength shift during irradiation and their mean wavelength of optical signal transmission in fibers will shift to a shorter wavelength in a low-dose-rate radiation environment. Finally, the change in the scale factor of IFOG resulting from the mean wavelength shift is estimated and tested, and it is found that the significant radiation-induced scale factor variation must be considered during the design of space-borne IFOGs. 展开更多
关键词 space radiation fiber optic gyroscope scale factor mean wavelength
下载PDF
LDPC Coding Scheme for Improving the Reliability of Multi-Level-Cell NAND Flash Memory in Radiation Environments 被引量:2
9
作者 Guangjun Ge Liuguo Yin 《China Communications》 SCIE CSCD 2017年第8期10-21,共12页
Utilizing commercial off-the-shelf(COTS) components in satellites has received much attention due to the low cost. However, commercial memories suffer severe reliability problems in radiation environments. This paper ... Utilizing commercial off-the-shelf(COTS) components in satellites has received much attention due to the low cost. However, commercial memories suffer severe reliability problems in radiation environments. This paper studies the low-density parity-check(LDPC) coding scheme for improving the reliability of multi-level-cell(MLC) NAND Flash memory in radiation environments. Firstly, based on existing physical experiment works, we introduce a new error model for heavyion irradiations; secondly, we explore the optimization of writing voltage allocation to maximize the capacity of the storage channel; thirdly, we design the degree distribution of LDPC codes that is specially suitable for the proposed model; finally, we propose a joint detection-decoding scheme based on LDPC codes, which estimates the storage channel state and executes an adaptive log-likelihood ratio(LLR) calculation to achieve better performance. Simulation results show that, compared with the conventional LDPC coding scheme, the proposed scheme may almost double the lifetime of the MLC NAND Flash memory in radiation environments. 展开更多
关键词 low-density parity-check(LDPC) coding multi-level-cell(MLC) NAND Flash memory joint detection-decoding commercial off-the-shelf(COTS) components space radiation environments
下载PDF
Radiation effects of electrons on multilayer FePS3studied with laser plasma accelerator
10
作者 Meng Peng Jun-Bo Yang +5 位作者 Hao Chen Bo-Yuan Li Xu-Lei Ge Xiao-Hu Yang Guo-Bo Zhang Yan-Yun Ma 《Chinese Physics B》 SCIE EI CAS CSCD 2022年第8期505-511,共7页
Space radiation with inherently broadband spectral flux poses a huge danger to astronauts and electronics on aircraft,but it is hard to simulate such feature with conventional radiation sources. Using a tabletop laser... Space radiation with inherently broadband spectral flux poses a huge danger to astronauts and electronics on aircraft,but it is hard to simulate such feature with conventional radiation sources. Using a tabletop laser-plasma accelerator, we can reproduce exponential energy particle beams as similar as possible to these in space radiation. We used such an electron beam to study the electron radiation effects on the surface structure and performance of two-dimensional material(Fe PS3).Energetic electron beam led to bulk sample cleavage and damage between areas of uneven thickness. For the Fe PS3sheet sample, electron radiation transformed it from crystalline state to amorphous state, causing the sample surface to rough.The full widths at the half maximum of characteristic Raman peaks became larger, and the intensities of characteristic Raman peaks became weak or even disappeared dramatically under electron radiation. This trend became more obvious for thinner samples, and this phenomenon was attributed to the cleavage of P–P and P–S bonds, destabilizing the bipyramid structure of [P2S6]4-unit. The results are of great significance for testing the maximum allowable radiation dose for the two-dimensional material, implying that Fe PS3cannot withstand such energetic electron radiation without an essential shield. 展开更多
关键词 space radiation laser–plasma interaction two-dimensional material Raman spectroscopy
下载PDF
On the immunological limitations of hibernation and synthetic torpor as a supporting technique for astronauts’ radioprotection in deep space missions
11
作者 Joseph J Bevelacqua James Welsh Seyed Mohammad Javad Mortazavi 《World Journal of Immunology》 2019年第1期1-4,共4页
Although human hibernation has been introduced as an effective technique in space exploration,there are concerns regarding the intrinsic risks of the approach(i.e.,synthetic torpor)and other factors involved in this p... Although human hibernation has been introduced as an effective technique in space exploration,there are concerns regarding the intrinsic risks of the approach(i.e.,synthetic torpor)and other factors involved in this procedure.Besides concerns about the brain changes and the state of consciousness during hibernation,an"Achilles heel"of the hibernation is the negative impact of torpor on factors such as the number of circulating leukocytes,complement levels,response to lipopolysaccharides,phagocytotic capacity,cytokine production,lymphocyte proliferation,and antibody production.Moreover,increased virulence of bacteria in deep space can significantly increase the risk of infection.The increased infection risk during long-term space missions with the combined effects of radiation and microgravity affect the astronauts’immune system.With these additional immune system stressors,torpor-induced extraimmunosuppression can be potentially life threatening for astronauts. 展开更多
关键词 space radiation HIBERNATION RADIOPROTECTION Synthetic torpor Immunology
下载PDF
Mitigating Deep Dielectric Charging Effects at the Orbits of Jovian Planets 被引量:2
12
作者 YU Xiangqian SONG Siyu +4 位作者 CHEN Hongfei ZONG Qiugang ZOU Hong SHI Weihong CHEN Ao 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI CSCD 2020年第5期804-815,共12页
Deep dielectric charging/discharging,caused by high energy electrons,is an important consideration in electronic devices used in space environments because it can lead to spacecraft anomalies and failures.The Jovian p... Deep dielectric charging/discharging,caused by high energy electrons,is an important consideration in electronic devices used in space environments because it can lead to spacecraft anomalies and failures.The Jovian planets,including Saturn,Uranus,Neptune and Jupiter’s moons,are believed to have robust electron radiation belts at relativistic energies.In particular,Jupiter is thought to have caused at least 42 internal electrostatic discharge events during the Voyager 1 flyby.With the development of deep space exploration,there is an increased focus on the deep dielectric charging effects in the orbits of Jovian planets.In this paper,GEANT4,a Monte Carlo toolkit,and radiation-induced conductivity(RIC)are used to calculate deep dielectric charging effects for Jovian planets.The results are compared with the criteria for preventing deep dielectric charging effects in Earth orbit.The findings show that effective criteria used in Earth orbit are not always appropriate for preventing deep dielectric charging effects in Jovian orbits.Generally,Io,Europa,Saturn(R_S=6),Uranus(L=4.73)and Ganymede missions should have a thicker shield or higher dielectric conductivity,while Neptune(L=7.4)and Callisto missions can have a thinner shield thickness or a lower dielectric conductivity.Moreover,dielectrics grounded with double metal layers and thinner dielectrics can also decrease the likelihood of discharges. 展开更多
关键词 Jovian planets orbits Earth orbits deep dielectric charging effect space radiation
下载PDF
NEW APPROACH TO EMULATE SEU FAULTS ON SRAM BASED FPGAS
13
作者 Reza Omidi Gosheblagh Karim Mohammadi 《Journal of Electronics(China)》 2014年第1期68-77,共10页
Field Programmable Gate Arrays(FPGAs)offer high capability in implementing of complex systems,and currently are an attractive solution for space system electronics.However,FPGAs are susceptible to radiation induced Si... Field Programmable Gate Arrays(FPGAs)offer high capability in implementing of complex systems,and currently are an attractive solution for space system electronics.However,FPGAs are susceptible to radiation induced Single-Event Upsets(SEUs).To insure reliable operation of FPGA based systems in a harsh radiation environment,various SEU mitigation techniques have been provided.In this paper we propose a system based on dynamic partial reconfiguration capability of the modern devices to evaluate the SEU fault effect in FPGA.The proposed approach combines the fault injection controller with the host FPGA,and therefore the hardware complexity is minimized.All of the SEU injection and evaluation requirements are performed by a soft-core which realized inside the host FPGA.Experimental results on some standard benchmark circuits reveal that the proposed system is able to speed up the fault injection campaign 50 times in compared to conventional method. 展开更多
关键词 Field Programmable Gate Arrays(FPGAs) Single-Event Upset(SEU) fault injection Soft-core space radiation effects
下载PDF
Direct measurement of the linear energy transfer of ions in silicon for space application 被引量:2
14
作者 CHEN HongFei YU XiangQian +7 位作者 SHAO SiPei SHI WeiHong CUI ZhanGuo XIANG HongWen HAO ZhiHua ZOU JiQing ZHONG WeiYing ZOU Hong 《Science China(Technological Sciences)》 SCIE EI CAS CSCD 2016年第1期128-134,共7页
The single event effect(SEE) is an important consideration in electronic devices used in space environments because it can lead to spacecraft anomalies and failures. The linear energy transfer(LET) of ions is commonly... The single event effect(SEE) is an important consideration in electronic devices used in space environments because it can lead to spacecraft anomalies and failures. The linear energy transfer(LET) of ions is commonly investigated in studies of SEE. The use of a thin detector is an economical way of directly measuring the LET in space. An LET telescope consists of a thin detector as the front detector(D1), along with a back detector that indicates whether D1 was penetrated. The particle radiation effect monitor(PREM) introduced in this paper is designed to categorize the LET into four bins of 0.2–0.4, 0.4–1.0, 1.0–2.0 and 2.0–20 Me V·cm^2/mg, and one integral bin of LET>20 Me V·cm^2/mg. After calibration with heavy ions and Geant4 analysis, the LET boundaries of the first four bins are determined to be 0.236, 0.479, 1.196, 2.254, and 17.551 Me V·cm^2/mg, whereas that of the integral bin is determined to be LET>14.790 Me V·cm^2/mg. The acceptances are calculated by Geant4 analysis as 0.452, 0.451, 0.476, 0.446, and 1.334, respectively. The LET accuracy is shown to depend on the thickness of D1; as D1 is made thinner, the accuracy of the measured values increases. 展开更多
关键词 linear energy transfer measurement LET single event effect space radiation
原文传递
Return to the Moon:New perspectives on lunar exploration
15
作者 Yangting Lin Wei Yang +24 位作者 Hui Zhang Hejiu Hui Sen Hu Long Xiao Jianzhong Liu Zhiyong Xiao Zongyu Yue Jinhai Zhang Yang Liu Jing Yang Honglei Lin Aicheng Zhang Dijun Guo Sheng Gou Lin Xu Yuyang He Xianguo Zhang Liping Qin Zongcheng Ling Xiongyao Li Aimin Du Huaiyu He Peng Zhang Jinbin Cao Xianhua Li 《Science Bulletin》 SCIE EI CAS CSCD 2024年第13期2136-2148,共13页
Lunar exploration is deemed crucial for uncovering the origins of the Earth-Moon system and is the first step for advancing humanity’s exploration of deep space.Over the past decade,the Chinese Lunar Exploration Prog... Lunar exploration is deemed crucial for uncovering the origins of the Earth-Moon system and is the first step for advancing humanity’s exploration of deep space.Over the past decade,the Chinese Lunar Exploration Program(CLEP),also known as the Chang’e(CE)Project,has achieved remarkable milestones.It has successfully developed and demonstrated the engineering capability required to reach and return from the lunar surface.Notably,the CE Project has made historic firsts with the landing and on-site exploration of the far side of the Moon,along with the collection of the youngest volcanic samples from the Procellarum KREEP Terrane.These achievements have significantly enhanced our understanding of lunar evolution.Building on this success,China has proposed an ambitious crewed lunar exploration strategy,aiming to return to the Moon for scientific exploration and utilization.This plan encompasses two primary phases:the first crewed lunar landing and exploration,followed by a thousand-kilometer scale scientific expedition to construct a geological cross-section across the lunar surface.Recognizing the limitations of current lunar exploration efforts and China’s engineering and technical capabilities,this paper explores the benefits of crewed lunar exploration while leveraging synergies with robotic exploration.The study refines fundamental lunar scientific questions that could lead to significant breakthroughs,considering the respective engineering and technological requirements.This research lays a crucial foundation for defining the objectives of future lunar exploration,emphasizing the importance of crewed missions and offering insights into potential advancements in lunar science. 展开更多
关键词 Crewed lunar exploration Water and volatiles Composition and structure of lunar interior Volcanic activity and evolution of lunar MANTLE space weathering and radiation environments Exploration technology
原文传递
Closed Timelike Curves in Type Ⅱ Non-Vacuum Spacetime
16
作者 Faizuddin Ahmed 《Communications in Theoretical Physics》 SCIE CAS CSCD 2017年第2期189-191,共3页
Here we present a cyclicly symmetric non-vacuum spacetime, admitting closed timelike curves(CTCs) which appear after a certain instant of time,i.e.,a time-machine spacetime. The spacetime is asymptotically flat, freef... Here we present a cyclicly symmetric non-vacuum spacetime, admitting closed timelike curves(CTCs) which appear after a certain instant of time,i.e.,a time-machine spacetime. The spacetime is asymptotically flat, freefrom curvature singularities and a four-dimensional extension of the Misner space in curved spacetime. The spacetime is of type Ⅱ in the Petrov classification scheme and the matter field pure radiation satisfy the energy condition. 展开更多
关键词 closed timelike curves Misner space pure radiation
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部