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Sensitivity investigation of 100-MeV proton irradiation to SiGe HBT single event effect

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Chinese Physics B 2024年第1期33卷 554-562页

作者：冯亚辉郭红霞刘益维欧阳晓平张晋新马武英张凤祁白如雪马晓华郝跃 State Key Laboratory of Wide Bandgap Semiconductor Devices School of MicroelectronicsXidian UniversityXi'an 710071China School of Materials Science and Engineering Xiangtan UniversityXiangtan 411105China School of Space Science and Technology Xidian UniversityXi'an 710071China State Key Laboratory of Experimental Simulation and Effects of Strong Pulse Radiation Northwest Institute of Nuclear TechnologyXi'an 710024China

The single event effect(SEE) sensitivity of silicon–germanium heterojunction bipolar transistor(Si Ge HBT) irradiated by 100-Me V proton is investigated. The simulation results indicate that the most sensitive position of the Si Ge HBT device is the emitter center, where the protons pass through the larger collector-substrate(CS) junction. Furthermore, in this work the experimental studies are also carried out by using 100-Me V proton. In order to consider the influence of temperature on SEE, both simulation and experiment are conducted at a temperature of 93 K. At a cryogenic temperature, the carrier mobility increases, which leads to higher transient current peaks, but the duration of the current decreases ***, at the same proton flux, there is only one single event transient(SET) that occurs at 93 K. Thus, the radiation hard ability of the device increases at cryogenic temperatures. The simulation results are found to be qualitatively consistent with the experimental results of 100-Me V protons. To further evaluate the tolerance of the device, the influence of proton on Si Ge HBT after gamma-ray(^(60)Coγ) irradiation is investigated. As a result, as the cumulative dose increases, the introduction of traps results in a significant reduction in both the peak value and duration of the transient currents.

关键词： silicon–germanium heterojunction bipolar transistor(Si Ge HBT) 100-Me V proton technology computer-aided design(TCAD) single event effect(SEE)

Influences of supply voltage on single event upsets and multiple-cell upsets in nanometer SRAM across a wide linear energy transfer range

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Chinese Physics B 2021年第4期30卷 596-604页

作者： Yin-Yong Luo Wei Chen feng-qi zhang Tan Wang State Key Laboratory of Intense Pulsed Radiation Simulation and Effect Northwest Institute of Nuclear TechnologyXi'an 710024China

The influences of reducing the supply voltage on single event upset(SEU) and multiple-cell upset(MCU) in two kinds of 65-nm static random access memories(SRAMs) are characterized across a wide linear energy transfer(LET) *** results show that the influence of the voltage variation on SEU cross section clearly depends on the LET value which is above heavy ion LET threshold no matter whether the SRAM is non-hardened 6 T SRAM or radiation-hardened double dual interlocked cells(DICE) *** the LET value is lower than the LET threshold of MCU,the SEU only manifests single cell upset,the SEU cross section increases with the decrease of *** lower the LET value,the higher the SEU sensitivity to the voltage variation *** the voltage has no evident influence on SEU cross section while the LET value is above the LET threshold of ***,the reduction of the voltage can result in a decrease in the highest-order MCU event cross section due to the decrease of charge collection efficiency of the outer sub-sensitive volume within a certain voltage *** further scaling the feature size of devices down,it is suggested that the dependence of SEU on voltage variation should be paid special attention to for heavy ions with very low LET or the other particles with very low energy for nanometer commercial off-the-shelf(COTS) SRAM.

关键词： supply voltage single event upsets multiple-cell upsets 65-nm SRAM double DICE SRAM

Synergistic effect of total ionizing dose on single event effect induced by pulsed laser microbeam on SiGe heterojunction bipolar transistor

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Chinese Physics B 2018年第10期27卷 612-621页

作者： Jin-Xin zhang Hong-Xia Guo Xiao-Yu Pan qi Guo feng-qi zhang Juan feng Xin Wang Yin Wei Xian-Xiang Wu Xidian University Xi'an 710126 China Xinjiang Technical Institute of Physics & Chemistry Chinese Academy of Sciences Urumqi 830011 China Northwest Institution of Nuclear Technology Xi'an 710024 China

The synergistic effect of total ionizing dose（TID） on single event effect（SEE） in SiGe heterojunction bipolar transistor（HBT） is investigated in a series of experiments. The SiGe HBTs after being exposed to 60 Co g irradiation are struck by pulsed laser to simulate SEE. The SEE transient currents and collected charges of the un-irradiated device are compared with those of the devices which are irradiated at high and low dose rate with various biases. The results show that the SEE damage to un-irradiated device is more serious than that to irradiated SiGe HBT at a low applied voltage of laser test. In addition, the g irradiations at forward and all-grounded bias have an obvious influence on SEE in the SiGe HBT, but the synergistic effect after cutting off the g irradiation is not significant. The influence of positive oxide-trap charges induced by TID on the distortion of electric field in SEE is the major factor of the synergistic effect. Moreover, the recombination of interface traps also plays a role in charge collection.

关键词： SiGe HBT synergistic effect single event effects total ionizing dose

Percutaneous Balloon Angioplasty for Severe Native Aortic Coarctation in Young Infants Less Than 6 Months： Medium- to Long-term Follow-up

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Chinese Medical Journal 2015年第8期128卷 1021-1025页

作者： Lan He Fang Liu Lin Wu Chun-Hua qi Li-feng zhang Guo-Ying Huang Pediatric Heart Center Children's Hospital of Fudan University Shanghai 201102 China

Background： Although balloon angioplasty （BA） has been performed for more than 20 years, its use as a treatment for native coarctation of the aorta （CoA） during childhood, especially in young infants, remains controversial. This study aimed to assess the effects and potential role ofpercutaneous transcatheter BA for native CoA as an alternative therapy to surgical repair in young infants. Methods： The 37 patients aged from 6 days to 6 months with severe CoA in congestive heart failure or circulatory shock were admitted for BA. Patient＇s weight ranged from 2.4 to 6.1 kg. All 37 patients were experiencing cardiac dysfunction, and eight patients were in cardiac shock with severe metabolic acidosis. Eleven patients had an isolated CoA, whereas the others had a CoA associated with other cardiac malformations. Cardiac catheterization and aortic angiography were performed under general anesthesia with intubation. Transfemoral arterial approaches were used for the BA. The size of the balloon ranged from 3 mm × 20 mm to 8 mm × 20 mm, and a coronary artery balloon catheter was preferred over a regular peripheral vascular balloon catheter. Results： The femoral artery was successfully punctured in all but one patient, with that patient undergoing a carotid artery puncture. The systolic peak pressure gradient （PG） across the coarctation was 41.0 ± 16.0 mmHg （range 13-76 mmHg）. The mean diameter of the narrowest coarctation site was 1.7 ± 0.6 mm （range 0.5-2.8 mm）. All patients had successful dilation; the PG significantly decreased to 13.0 ± 11.0 mmHg （range 0-40 mmHg）, and the diameter ofcoarctation significantly improved to 3.8 ± 0.9 mm （range 2.5-5.3 mm）. No intraoperative complications occurred for any patients. However, in one case that underwent a carotid artery puncture, a giant aneurysm formed at the puncture site and required surgical repair. The following observations were made during the follow-up period from 6-month to 7-year：（1） The PG across the coarctation measur

关键词： Native Aortic Coarctation Percutaneous Balloon Angioplasty Young Infants

Visible Light Indoor Positioning System Based on Pisarenko Harmonic Decomposition and Neural Network

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Chinese Journal of Electronics 2024年第1期33卷 195-203页

作者： Li ZHAO Yi REN qi WANG Lange DENG feng zhang School of Electronic Information Engineering Xi’an Technological University

Visible-light indoor positioning is a new generation of positioning technology that can be integrated into smart lighting and optical communications. The current received signal strength(RSS)-based visible-light positioning systems struggle to overcome the interferences of background and indoor-reflected noise. Meanwhile, when ensuring the lighting, it is impossible to use the superposition of each light source to accurately distinguish light source information; furthermore, it is difficult to achieve accurate positioning in complex indoor environments. This study proposes an indoor positioning method based on a combination of power spectral density detection and a neural network. The system integrates the mechanism for visible-light radiation detection with RSS theory, to build a back propagation neural network model fitting for multiple reflection channels. Different frequency signals are loaded to different light sources at the beacon end, and the characteristic frequency and power vectors are obtained at the location end using the Pisarenko harmonic decomposition method. Then, a complete fingerprint database is established to train the neural network model and conduct location tests. Finally, the location effectiveness of the proposed algorithm is verified via actual positioning experiments. The simulation results show that, when four groups of sinusoidal waves with different frequencies are superimposed with white noise, the maximum frequency error is 0.104 Hz and the maximum power error is 0.0362 W. For the measured positioning stage, a 0.8 m × 0.8 m × 0.8 m solid wood stereoscopic positioning model is constructed, and the average error is 4.28 cm. This study provides an effective method for separating multi-source signal energies, overcoming background noise, and improving indoor visible-light positioning accuracies.

关键词： Neural networks Measurement uncertainty Position measurement Harmonic analysis Light emitting diodes Frequency estimation Indoor positioning systems

Contrast Dose and Radiation Dose Reduction in Abdominal Enhanced Computerized Tomography Scans with Single-phase Dual-energy Spectral Computerized Tomography Mode for Children with Solid Tumors

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Chinese Medical Journal 2017年第7期130卷 823-831页

作者： Tong Yu Jun Gao Zhi-Min Liu qi-feng zhang Yong Liu Ling Jiang Yon Peng Imaging Center Beijing Children's Hospital Capital Medical University Beijing 100045 China

Background：Contrast dose and radiation dose reduction in computerized tomography （CT） scan for adult has been explored successfully,but there have been few studies on the application of low-concentration contrast in pediatric abdominal CT *** was a feasibility study on the use of dual-energy spectral imaging and adaptive statistical iterative reconstruction （ASiR） for the reduction of radiation dose and iodine contrast dose in pediatric abdominal CT patients with solid ***：Forty-five patients with solid tumors who had initial CT （Group B） and follow-up CT （Group A） after chemotherapy were *** initial diagnostic CT scan （Group B） was performed using the standard two-phase enhanced CT with 320 mgI/ml concentration contrast,and the follow-up scan （Group A） was performed using a single-phase enhanced CT at 45 s after the beginning of the 270 mgI/ml contrast injection using spectral *** percent ASiR was used for the images in Group B and monochromatic images with energy levels ≥60 keV in Group *** addition,filtered back-projection （FBP） reconstruction was used for monochromatic images 〈60 keV in Group *** total radiation dose,total iodine load,contrast injection speed,and maximum injection pressure were compared between the two *** 40 keV and 60 keV spectral CT images of Group A were compared with the images of Group B to evaluate overall image ***：The total radiation dose,total iodine load,injection speed,and maximum injection pressure for Group A were decreased by 19%,15%,34.4%,and 18.3%,*** optimal energy level in spectral CT for displaying the abdominal vessels was 40 *** this level,the CT values in the abdominal aorta and its three branches,the portal vein and its two branches,and the inferior vena cava were all greater than 340 hounsfield unit （HU）.The abdominal organs of Groups A and B had similar degrees of absolute and relative enhancement （t =0.36 and-1.716 for liver,0.153 and-1.546

关键词： Contrast Dose Reduction Pediatric Radiation Dose Reduction Solid Tunlors

Analyzing the spatiotemporal evolution and driving forces of gross ecosystem product in the upper reaches of the Chaobai River Basin

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Frontiers of Environmental Science & Engineering 2024年第8期18卷 117-132页

作者： Jiacheng Li qi Han Liqiu zhang Li feng Guihuan Liu Beijing Key Laboratory for Source Control Technology of Water Pollution College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China Engineering Research Center for Water Pollution Source Control&Eco-remediation College of Environmental Science and EngineeringBeijing Forestry UniversityBeijing 100083China Center of Eco-compensation Chinese Academy of Environmental PlanningMinistry of Ecology of EnvironmentBeijing 100041China

The Chaobai River Basin,which is a crucial ecological barrier and primary water source area within the Beijing-Tianjin-Hebei region,possesses substantial ecological *** gross ecosystem product(GEP)in the Chaobai River Basin is a reflection of ecosystem conditions and quantifies nature’s contributions to humanity,which provides a basis for basin ecosystem service management and *** study investigated the spatiotemporal evolution of GEP in the upper Chaobai River Basin and explored the driving factors influencing GEP spatial *** patterns from 2005 to 2020 were analyzed,and GEP was calculated for 2005,2010,2015,and *** driving factors influencing GEP spatial differentiation were identified using the optimal parameter-based geographical detector(OPGD)*** key findings are as follows:(1)From 2005 to 2020,the main ecosystem types were forest,grassland,and *** areas experienced significant changes,and conversions mainly occurred among urban,water,grassland and agricultural ecosystems.(2)Temporally,the GEP in the basin increased from 2005 to 2020,with regulation services *** the county(district)scale,GEP exhibited a north-west-high and south-east-low pattern,showing spatial differences between per-unit-area GEP and county(district)GEP,while the spatial variations in per capita GEP and county(district)GEP were similar.(3)Differences in the spatial distribution of GEP were influenced by regional natural geographical and socioeconomic *** these factors,gross domestic product,population density,and land-use degree density contributed *** among different driving forces noticeably impacted GEP spatial *** findings underscore the necessity of incorporating factors such as population density and the intensity of land-use development into ecosystem management decision-making processes in the upper reaches of the Chaobai River *** policies

关键词： Ecosystem pattern Gross ecosystem product(GEP) Spatiotemporal evolution Optimal parameter-based geographical detector(OPGD) Chaobai River Basin

Sap Flow of Populus euphratica in a Desert Riparian Forest in an Extreme Arid Region During the Growing Season

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Journal of Integrative Plant Biology 2007年第4期49卷 425-436页

作者： Jian-Hua Si qi feng Xiao-You zhang Zong-qiang Chang Yong-Hong Su Hai-Yang Xi Cold and Arid Region Environmental and Engineering Research Institute the Chinese Academy of Sciences Alashan Desert Eco-hydrology Experimental Research Station Lanzhou 730000 China

In the present study, the heat pulse technique was applied to investigate the stem sap flow of Populus euphratica in a desert riparian forest in an extreme arid region from April to October 2003 and from May to October 2004. The experimental sites were in qidaoqiao （101 °10′ E, 41°59′ N） and Bayantaolai farm （101°14′ E, 42°01′ N） in Ejina county, in the low reaches of the Heihe River, China. The results indicated that the diurnal change in the velocity of sap flow showed minor fluctuations. At night, the rising of sap flow could be observed in the main tree species because of root pressure. During the growing season, the maximum average velocity was observed in July, followed by August, and the same velocity was observed in September and May; the minimum velocity was observed in October. The transpiration from June to August during the growing season accounted for approximately 70% of the annual total transpiration. The sap flow velocity of P. euphratica trees of different ages could be arranged in the order： 15 yr 〉 25 yr 〉 50 yr. Sap flow velocity was closely related to changes in micrometeorological factors, with average sap flow velocity showing a significant linear correlation with net radiation, air temperature and relative humidity.

关键词： desert riparian forest extreme arid region heat-pulse technique Populus euphratica sap flow velocity.

Enhancing the peroxidase-like activity of MoS_(2)-based nanozymes by introducing attapulgite for antibacterial application and sensitive detection of glutathione

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Nano Research 2024年第8期17卷 7415-7426页

作者： feng feng Yihe zhang Xiao zhang Bin Mu Jiahe zhang Wenjie Qu Wangshu Tong Minmin Liang qi An Zhanjun Guo Lu Zhao Engineering Research Center of Ministry of Education for Geological Carbon Storage and Low Carbon Utilization of Resources Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid WastesNational Laboratory of Mineral MaterialsSchool of Materials Science and TechnologyChina University of Geosciences(Beijing)Beijing 100083China Key Laboratory of Clay Mineral Applied Research of Gansu Province Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou 730000China Experimental Center of Advanced Materials School of Materials Science and Engineering School of Materials Science and EngineeringBeijing Institute of TechnologyBeijing 100081China

Nanozymes are next-generation of nanomaterials with enzyme-like *** particular,nanozymes with peroxidase(POD)-like activity have been utilized in various fields,including antibacterial,detection,degradation,***,their extensive applications were limited by their low catalytic activity ***,we have presented a composite nanozyme based on attapulgite(ATP)(Fe-ATP-MoS_(2)(FAM)),which exhibited enhanced POD-like activity(185.33 U·mg^(−1)),4.25 times higher than that of Fe-MoS_(2)(FM)(43.63 U·mg^(−1)).The density functional theory(DFT)calculations indicated that the addition of ATP increased the electron density of metal centers(Mo and Fe).More importantly,Michaelis–Menten kinetics revealed that the introduction of ATP significantly enhanced the binding affinities of substrates through the pores of ATP,forming a highly concentrated substrate microenvironment and thus promoting its POD-like ***,from molecular size and kinetic analysis,we proposed that the changes in substrate size before and after oxidation also significantly affected its Michaelis-constant(Km)***,we utilized FAM in the applications of highly effective antibacterial application and sensitive detection of glutathione(GSH).In conclusion,this work provides a novel approach for designing a highly efficient nanozyme based on natural mineral composites.

关键词： attapulgite peroxidase electron density affinity antibacterial