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IPS observation system for the Miyun 50m radio telescope and its commissioning observation

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Research in Astronomy and Astrophysics 2012年第7期12卷 857-864页

作者： Xin-Ying Zhu Xi-Zhen zhang hong-bo zhang De-Qing Kong Hui-Peng Qu National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Beijing Institute of Tracking and Telecommunications Technology Beijing 100094 China

Ground-based observation of Interplanetary Scintillation （IPS） is an impor- tant approach for monitoring solar wind. A ground-based IPS observation system has been newly implemented on a 50 m radio telescope at Miyun station, managed by the National Astronomical Observatories, Chinese Academy of Sciences. This observa- tion system has been constructed for the purpose of observing solar wind speed and the associated scintillation index by using the normalized cross-spectrum of a simul- taneous dual-frequency IPS measurement. The system consists of a universal dual- frequency front-end and a dual-channel multi-function back-end specially designed for IPS. After careful calibration and testing, IPS observations on source 3C 273B and 3C 279 have been successfully carried out. The preliminary observation results show that this newly-developed observation system is capable of performing IPS observa- tion. The system＇s sensitivity for IPS observation can reach over 0.3 Jy in terms of an IPS polarization correlator with 4 MHz bandwidth and 2 s integration time.

关键词： instrument - interplanetary scintillation -- telescope -- radio astron-omy

CO Clouds around SNR G21.8-0.6 and G32.8-0.1

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Chinese Journal of Astronomy and Astrophysics 2007年第5期7卷 705-711页

作者： Jian-Jun Zhou Xi-Zheng zhang hong-bo zhang Jarken Esimbek Ju-Yong zhang Bing-Gang Ju National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 National Astronomical Observatories / Urumqi Observatory Chinese Academy of Sciences Urumqi 830011 Graduate School of Chinese Academy of Sciences Beijing 100049 Qinghai Station of Purple Mountain Observatory Chinese Academy of Sciences Delingha 817000

We made the first CO（1-0） mapping to SNR G21.8-0.6 and SNR G32.8-0.1, both associated with OH 1720MHz maser. Based on the morphological correspondence and velocity and position agreement between the radio remnant an... 详细信息

关键词： ISM clouds -- ISM individual (G21.8-0.6, G32.8-0.1 ) -- ISM molecules -- masers -- supernova remnants

Mechanical thrombectomy for acute occlusion of the posterior inferior cerebellar artery: A case report

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World Journal of Clinical Cases 2021年第10期9卷 2268-2273页

作者： hong-bo zhang Pian Wang Yan Wang Jiang-hong Wang Zheng Li Rong Li Department of Neurology Chengdu Fifth People's HospitalChengdu 611130Sichuan ProvinceChina

BACKGROUND Mechanical thrombectomy(MT)has been demonstrated to be useful for the treatment of ischemic stroke in patients with large vessel ***,recanalization by MT is not recommended for distal vessels such as second-order branches of the middle cerebral artery and posterior inferior cerebellar artery(PICA).Because of the small size and tortuosity of these arteries,the risks of using the available endovascular devices outweigh the benefits of ***,MT appears to be effective in patients with primary distal vessel occlusion in eloquent areas,those with a high National Institutes of Health Stroke Scale score,and those ineligible for recombinant tissue plasminogen activator ***,we report the use of MT for treating acute occlusion of the PICA using a directaspiration first-pass technique(ADAPT).CASE SUMMARY In this case,the patient received acute occlusion of the PICA with ADAPT when right internal carotid artery stenting was *** With the introduction of advanced endovascular devices,MT may now be a feasible treatment for acute occlusion of the PICA.

关键词： Posterior inferior cerebellar artery Mechanical thrombectomy Ischemic stroke Carotid artery stent Neurovascular interventions Case report

Gravitational Deformation Measurement Method for the Main Reflector and Sub-reflector of the 70 m Antenna by Laser Scanner

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Research in Astronomy and Astrophysics 2022年第9期22卷 1-9页

作者： Lian-bo Fu Jian-Jun Liu Wei Yan De-Qing Kong Xin Ren Chen-Di Liu hong-bo zhang Key Laboratory of Lunar and Dep Space Exploration National Astronomical ObservatoriesChinese Academy of SciencesBejing 100101China Urunaivreyr of Chinese Academy of Sciences Beijing 100049China

Large antennas play an important role in deep space exploration and astronomical research. However, their performances are inevitably affected by the main reflector surface deformation and sub-reflector displacement resulting from the factors of wind, temperature, and gravity, among which the effect of gravity is especially pronounced. In this work, a three-dimensional laser scanner was employed to measure the main reflector and subreflector gravitational deformation of the Tianjin 70 m antenna at different elevation angles. Here, we solved the antenna main reflector deformation and sub-reflector displacement, and analyzed the deformation law of the antenna under the action of gravity. A new measurement method of antenna main reflector deformation and subreflector displacement is realized by mutual verification of the measured results and theoretical simulations. This method will help to improve the antenna performance and provide a reference to optimize the design of largeaperture antennas.

关键词： telescopes techniques:radar astronomy planets and satellites:detection

Effects of proteinase A on cultivation and viability characteristics of industrial Saccharomyces cerevisiae WZ65

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第10期10卷 769-776页

作者： hong-bo zhang Hai-feng zhang Qi-he CHEN Hui RUAN Ming-liang FU Guo-qing HE Department of Food Science and Nutrition Zhejiang University Hangzhou 310029 China

Proteinase A （PrA）, encoded by PEP4 gene, is a key enzyme in the vacuoles of Saccharomyces cerevisiae. We characterized the effects of PrA on cell growth and glucose metabolism in the industrial S. cerevisiae WZ65. It was observed that the lag phase of cell growth of partial PEP4 gene deletion mutant （36 h） and PrA-negative mutant （48 h） was significantly extended, compared with the wild type strain （24 h）（P〈0.05）, but PrA had no effect on glucose metabolism either under shaking or steady state cultivations. The logistic model was chosen to evaluate the effect of PrA on S. cerevisiae cell growth, and PrA was found to promote cell growth against insufficient oxygen condition in steady state cultivation, but had no effect in shaking cultivation. The effects of glucose starvation on cell growth of partial PEP4 gene deletion strain and PrA-negative mutant were also evaluated. The results show that PrA partial deficiency increased the adaption ofS. cerevisiae to unfavorable nutrient environment, but had no effect on glucose metabolism under the stress of low glucose. During heat shock test, at 60 ℃ the reduced cell viability rate （RCVR） was 10% for the wild type S. cerevisiae and 90% for both mutant strains （P〈0.01）, suggesting that PrA was a negative factor for S. cerevisiae cells to survive under heat shock. As temperatures rose from 60 ℃ to 70℃, the wild type S. cerevisiae had significantly lower relative glucose consumption rate （RGCR）（61.0% and 80.0%） than the partial mutant （78.0% and 98.5%） and the complete mutant （80.0% and 98.0%）（P〈0.05）, suggesting that, in coping with heat shock, cells of the PrA mutants increased their glucose consumption to survive. The present study may provide meaningful information for brewing industry; however, the role of PrA in industrial S. cerevisiae physiology is complex and needs to be further investigated.

关键词： Proteinase A (PrA) PEP4 gene Saccharomyces cerevisiae WZ65 Cell metabolism Viability

Construction of recombinant industrial Saccharomyces cerevisiae strain with bglS gene insertion into PEP4 locus by homologous recombination

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第7期9卷 527-535页

作者： Qiang zhang Qi-he CHEN Ming-liang FU Jin-ling WANG hong-bo zhang Guo-qing HE Department of Food Science and Nutrition Zhejiang University Hangzhou 310029 China

The bglS gene encoding endo-1,3-1,4-β-glucanase from Bacillus subtil＆ was cloned and sequenced in this study. The bglS expression cassette, including PGK1 promoter, bglS gene fused to the signal sequence of the yeast mating pheromone a-factor （MFals）, and ADH1 terminator with G418-resistance as the selected marker, was constructed. Then one of the PEP4 allele of Saccharomyces cerevisiae WZ65 strain was replaced by bglS expression cassette using chromosomal integration of polymerase chain reaction （PCR）-mediated homologous recombination, and the bglS gene was expressed simultaneously. The recombinant strain S. cerevisiae （SC-βG） was preliminarily screened by the clearing hydrolysis zone formed after the barley β-glucan was hydrolyzed in the plate and no proteinase A （PrA） activity was measured in fermenting liquor. The results of PCR analysis of genome DNA showed that one of the PEP4 allele had been replaced and bglS gene had been inserted into the locus of PEP4 gene in recombinant strains. Different endo-1,3-1,4-β-glucanase assay methods showed that the recombinant strain SC-βG had high endo-1,3-1,4-β-glucanase expression level with the maximum of 69.3 U/（h·ml） after 60 h of incubation. Meanwhile, the Congo Red method was suitable for the determination of endo-1,3-1,4-β-glucanase activity during the actual brewing process. The current research implies that the constructed yeast strain could be utilized to improve the industrial brewing property of beer.

关键词： Endo-1 3-1 4-β-glucanase (bglS) Gene replacement Homologous recombination Bacillus subtilis PEP4 gene Saccharomyces cerevisiae

A new calibration model for pointing a radio telescope that considers nonlinear errors in the azimuth axis

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Research in Astronomy and Astrophysics 2014年第6期14卷 733-740页

作者： De-Qing Kong Song-Gen Wang Jin-Qing Wang Min Wang hong-bo zhang National Astronomical Observatories Chinese Academy of Sciences College of Mechanical Engineering Hangzhou Dianzi University Shanghai Astronomical Observatory Chinese Academy of Sciences Yunnan Observatories Chinese Academy of Sciences

A new calibration model of a radio telescope that includes pointing error is presented, which considers nonlinear errors in the azimuth axis. For a large radio telescope, in particular for a telescope with a turntable, it is difficult to correct pointing errors using a traditional linear calibration model, because errors produced by the wheel-on-rail or center bearing structures are generally nonlinear. Fourier expansion is made for the oblique error and parameters describing the inclination direction along the azimuth axis based on the linear calibration model, and a new calibration model for pointing is derived. The new pointing model is applied to the 40 m radio telescope administered by Yunnan Observatories, which is a telescope that uses a turntable. The results show that this model can significantly reduce the residual systematic errors due to nonlinearity in the azimuth axis compared with the linear model.

关键词： telescopes - antennas - pointing models

New radio observations of the Moon at L band

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Research in Astronomy and Astrophysics 2012年第9期12卷 1297-1312页

作者： Xi-Zhen zhang Andrew Gray Yan Su Jun-Duo Li Tom Landecker hong-bo zhang Chun-Lai Li National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China zxz @ nao. cas. cn Dominion Radio Astrophysical Observatory Penticton BC V2A 6K3 Canada

We present results of new radio observations of the Moon at L band with the synthesis telescope of the Dominion Radio Astrophysical Observatory Synthesis Telescope. The resolution and temperature sensitivity of the observations are 159 × 87 and 1.7K, respectively. The main results are: (1) the lunar brightness temperature averaged over the whole disk is about 233K while the average brightness temperature for the four quadrants are 228.1K (NE), 239.7K (NW), 233.9K (SW) and 228.8K (SE). The observations reveal large temperature and spatial variations on the Moon for the first time. The highest brightness temperature is about 257 K and it is located along the lunar equator, to the west. The total uncertainty is about 5% due to the absolute accuracy of the fluxes of the primary calibrators; (2) the total degree of po- larization is about 6%. both polarization intensity and degree of polarization increase from the disk’s center to the limb, and the distribution of the degree of polarization along the limb is not uniform; (3) the new data are used to study the properties of regolith, such as dielectric constant and thickness distribution. The results show that the lunar regolith’s thickness increases from the NW (mare area) to the SE (highland area) regions on the lunar surface.

关键词： techniques: high angular resolution-imaging processing — radio contin- uum: Moon

Sub-100 nm hollow SnO_2@C nanoparticles as anode material for lithium ion batteries and significantly enhanced cycle performances

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Chinese Chemical Letters 2015年第10期26卷 1293-1297页

作者： Shuang-Lei Yang Bang-hong Zhou Mei Lei Lan-Ping Huang Jun Pan Wei Wu hong-bo zhang State Key Laboratory for Powder Metallurgy Central South University Laboratory of Printable Functional Nanomaterials and Printing Electronics School of Printing and Packaging Wuhan University Department of Physics and Materials Science City University of Hong Kong

Rational designing and controlling of nanostructures is a key factor in realizing appropriate properties required for the high-performance energy fields. In the present study, hollow Sn O2@C nanoparticles（NPs） with a mean size of 50 nm have been synthesized in large-scale via a facile hydrothermal *** morphology and composition of as-obtained products were studied by various characterized techniques. As an anode material for lithium ion batteries（LIBs）, the as-prepared hollow Sn O2@C NPs exhibit significant improvement in cycle performances. The discharge capacity of lithium battery is as high as 370 m Ah g 1, and the current density is 3910 m A g 1（5 C） after 573 cycles. Furthermore, the capacity recovers up to 1100 m Ah g 1at the rate performances in which the current density is recovered to 156.4 m A g 1（0.2 C）. Undoubtedly, sub-100 nm Sn O2@C NPs provide significant improvement to the electrochemical performance of LIBs as superior-anode nanomaterials, and this carbon coating strategy can pave the way for developing high-performance LIBs.

关键词： Tin oxide nanoparticles Carbon coating Lithium ion batteries Anode nanomaterials Size-controllable synthesis