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Detection of two bright radio bursts from magnetar SGR 1935 + 2154 期刊论文
Nature Astronomy, 2021, 卷号: 5, 页码: 414
作者:  Kirsten, F.;  Snelders, M. P.;  Jenkins, M.;  Nimmo, K.;  van den Eijnden, J.
收藏  |  浏览/下载：41/0  |  提交时间：2021/11/18
Astrophysics - High Energy Astrophysical Phenomena  Abstract: Fast radio bursts are millisecond-duration, bright radio signals (fluence 0.1-100 Jy ms) emitted from extragalactic sources of unknown physical origin. The recent CHIME/FRB and STARE2 detection of an extremely bright (fluence ~MJy ms) radio burst from the Galactic magnetar SGR 1935+2154 supports the hypothesis that (at least some) fast radio bursts are emitted by magnetars at cosmological distances. In follow-up observations totalling 522.7 h on source, we detect two bright radio bursts with fluences of 112 ± 22 Jy ms and 24 ± 5 Jy ms, respectively. Both bursts appear to be affected by interstellar scattering and we measure significant linear and circular polarization for the fainter burst. The bursts are separated in time by ~1.4 s, suggesting a non-Poissonian, clustered emission processsimilar to those seen in some repeating fast radio bursts. Together with the burst reported by CHIME/FRB and STARE2, as well as a much fainter burst seen by FAST (fluence 60 mJy ms), our observations demonstrate that SGR 1935+2154 can produce bursts with apparent energies spanning roughly seven orders of magnitude, and that the burst rate is comparable across this range. This raises the question of whether these four bursts arise from similar physical processes, and whether the fast radio burst population distribution extends to very low energies (~1030 erg, isotropic equivalent).  
黄海桑沟湾水体及沉积物中微塑料污染特征研究 期刊论文
海洋环境科学, 2019, 卷号: 38, 期号: 2, 页码: 198-204
作者:  熊宽旭;  赵新月;  周倩;  付传城;  涂晨
收藏  |  浏览/下载：34/0  |  提交时间：2020/06/17
桑沟湾  微塑料  潮滩  丰度  空间分布  Sanggou bay  microplastics  tidal flats  abundance  spatial distribution  In recent years,research on microplastics pollution in the marine environment has been increasing,but studies on microplastics in water bodies and sediments of the bay under the influence of high-intensity human activities are still rarely reported. In this study,the pollution characteristics of microplastics in the wayer and sediments of Sanggou bay were investigated in December 2017,after the harvest of large-scale aquaculture,with the aim to study the effects of aquaculture activities and hydrodynamics on pollution characteristics and spatial distribution of microplastics in the bay. The results showed that the types of microplastics in the water and sediments of Sanggou bay were mainly fibers,fragments,films,foams and particles. The microplastic abundances in the water and sediments were 1.8 ~ 31.2 N/L,31.2 ~ 1246.8 N/kg,respectively. The average particle sizes of microplastics in water and sediments were 0.51 0.20 mm and 1.54 1.02 mm,respectively. The results of spatial distribution of microplastics in Sanggou bay showed that the high abundance area mainly appears in the inshore waters,and the abundance of microplastics tends to decrease from the inner areas of estuary to the outshore areas. The heterogeneity of microplastic abundance and spatial distribution in Sanggou bay is mainly affected by human activities such as aquaculture,living and shipping,as well as hydrodynamics. In the future,fine sampling and analysis are needed to fully understand the temporal and spatial distribution of microplastics pollution in the bay areas.  
Hydration kinetics, freeze-thaw resistance, leaching behavior of blended cement containing co-combustion ash of sewage sludge and rice husk 期刊论文
Construction and Building Materials, 2017, 卷号: 131, 页码: 361-370
作者:  Wang, Teng;  Xue, Yongjie;  Zhou, Min;  Lv, Yi;  Chen, Yuchi
收藏  |  浏览/下载：3/0  |  提交时间：2019/12/04
HMs  represents heavy metals  RHA  represents rice husk ash  F-T  represents freezethaw  H  represents final ash from co-combustion of 20% sewage sludge + 80% rice husk  W  represents final ash from co-combustion of 30% sewage sludge + 70% rice husk  PC  represents pozzolanic cement  C10  represents pure pozzolanic cement pastes  W3C7  represents cement pastes composed of 30% W and 70% PC  H3C7  represents cement pastes composed of 30% H and 70% PC  C10-5T and C10-10T  represent pure pozzolanic cement pastes exposed to 5 and 10  F-T  cycles, respectively  W3C7-5T and W3C7-10T  represent blended cement pastes composed of 30% W and 70% PC, exposed to 5 and 10 F-T cycles respectively  H3C7-5T and H3C7-10T  represent blended cement pastes composed of 30% H and 70% PC exposed to 5 and 10 F-T cycles respectively  FTHM  leaching concentration of HM during F-T cycle  Co-combustion ash  Blended cements  Hydration kinetics  Freeze-thaw durability  Environmental performance  
Effects of tannins on the fatty acid profiles of rumen fluids and milk from lactating goats fed a total mixed ration containing rapeseed oil 期刊论文
Livestock Science, 2017, 卷号: 204, 页码: 16-24
作者:  Abo-Donia, F. M.;  Yang, L. Y.;  Hristov, A. N.;  Wang, M.;  Tang, S. X.*
收藏  |  浏览/下载：10/0  |  提交时间：2019/12/23
ADFom  ash-free acid detergent fiber  ALA  α-Linolenic acid  BH  biohydrogenation  CLA  conjugated linoleic acid  CP  crude protein  DHA  docosahexenoic acid  DM  dry matter  DPA  docosapentenoic acid  EE  ether extract  EPA  eicosapentaenoic acid  LTAN  linear effects of TAN  MUFA  monounsaturated fatty acids  ND  no detected  NDFom  ash-free neutral detergent fiber  NFC  non-fiber carbohydrate  OA  oleic acid  OM  organic matter  PUFA  polyunsaturated fatty acids  QTAN  quadratic effects of TAN  RA  rumenic acid  SCD  stearoyl Co-A desaturase enzyme  SEM  standard error of least squares means  SFA  saturated fatty acids  TAN3， TAN6 and TAN9  ration containing tannins at 3, 6 and 9 g/kg of DM respectively  UFA  unsaturated fatty acids  VA  vaccenic acid  Hydrolysable tannin  Rapeseed oil  Fatty acid  Conjugated linoleic acid  Goat  
Clinicopathological significance and potential drug target of CDH1 in breast cancer: a meta-analysis and literature review 期刊论文
Drug Design, Development and Therapy, 2015, 卷号: 9, 页码: 5277-5285
作者:  Huang, Ruixue;  Ding, Ping;  Yang, Fei*
收藏  |  浏览/下载：15/0  |  提交时间：2019/12/03
CDH1  as a tumor suppressor gene  contributes sporadic breast cancer (BC) progression. However  the association between CDH1 hypermethylation and BC  and its clinicopathological significance remains unclear. We conducted a meta-analysis to investigate the relationship between the CDH1 methylation profile and the major clinicopathological features. A detailed literature was searched through the electronic databases PubMed  Web of Science™  and EMBASE™ for related research publications. The data were extracted and assessed by two reviewers independently. Odds ratios (ORs) with corresponding confidence intervals (CIs) were calculated and summarized respectively. The frequency of CDH1 methylation was significantly higher in invasive ductal carcinoma than in normal breast tissues (OR =5.83  95% CI 3.76–9.03  P<0.00001). CDH1 hypermethylation was significantly higher in estrogen receptor (ER)-negative BC than in ER-positive BC (OR =0.62  95% CI 0.43–0.87  P=0.007). In addition  we found that the CDH1 was significantly methylated in HER2-negative BC than in HER2-positive BC (OR =0.26  95% CI 0.15–0.44  P<0.00001). However  CDH1 methylation frequency was not associated with progesterone receptor (PR) status  or with grades  stages  or lymph node metastasis of BC patients. Our results indicate that CDH1 hypermethylation is a potential novel drug target for developing personalized therapy. CDH1 hypermethylation is strongly associated with ER-negative and HER2-negative BC  respectively  suggesting CDH1 methylation status could contribute to the development of novel therapeutic approaches for the treatment of ER-negative or HER2-negative BC with aggressive tumor biology.  
Synthesis, characterization, and ethylene polymerization behaviors of late-transition metal complexes coordinated with chlorinated bis(arylimino)pyridine ligand 期刊论文
polymer, 2014, 卷号: 55, 期号: 18, 页码: 4611-4618
Liu, Heng; Wang, Feng; Liu, Li; Jai,Xiang-Yu; Zheng,Wenjie; Guo,Jun; Zhang,Chun-Yu; Bai,Chen-Xi; Hu,Yan-Ming; Zhang,Xue-Quan
收藏  |  浏览/下载：20/0  |  提交时间：2015/10/20
A series of late-transition metal complexes supported with chlorinated bis(arylimino)pyridine ligands [2  Ar = 2  Ar = 2  Ar = 2  Ar = 4-Cl-2  Ar = 4-Br-2  6-(ArN=CCl)(2)C5H3N]MtCl(2) (Ar = 2  6-(Pr2C6H3)-Pr-i  6-Et2C6H3  6-Me2C6H3  6-Me2C6H2  6-Me2C6H2  4  Mt = Fe (1b)  Mt = Co (1c)  Mt = Fe (1d)  Mt = Fe (1e)  Mt = Fe (1f)  6-Me3C6H2  Co (2b)  Ni (3c)  Co (2d)  Co (2e)  Co (2f)) were synthesized. At the presence of methylaluminoxane (MAO)  Mt = Fe (1a)  Fe(II)- and Co(II)- based complexes were highly active towards ethylene polymerization  Co (2a)  affording polymers with bimodal and unimodal molar. mass distributions  Ni (3a)  respectively  while the Ni(II)-based complexes gave no polymer products. Moreover  the obtained polyethylenes were predominately saturated and vinyl-terminated for Fe(II)- and Co(II)-based complexes  respectively. Changing the ligand environment  polymerization parameters also posed a great influence on the catalytic activities and the properties of the resulting polymers. (C) 2014 Elsevier Ltd. All rights reserved.  
Structural design of large aperture rectangular mirror for space telescope (EI CONFERENCE) 会议论文
2nd International Conference on Civil Engineering and Transportation, ICCET 2012, October 27, 2012 - October 28, 2012, Guilin, China
Li Z.
收藏  |  浏览/下载：27/0  |  提交时间：2013/03/25
Structural design of large aperture mirror is one of the key technologies for space telescope development. To meet the requirements of high stiffness  strength and thermal dimensional stability  some factors such as support scheme  materials selection  lightweight design and flexible support design were taken into account. The three supports location of the mirror was determined according to the modal analytical solution. By adjusting the parameters of flexure hinge  influences of gravity  assembly stress and thermal stress on the mirror were reduced obviously. Finite element analysis (FEA) results indicate that the surface accuracy reach to rms10.2nm and 10.8nm under the gravity along optical axis direction and 5C uniform temperature rise respectively  the fundamental frequency of the mirror component is 268Hz. Dynamics test shows that the first order natural frequency is 256Hz  which shows an error less than 5% compared to FEA results. (2013) Trans Tech Publications  Switzerland.  
Structural design and simulation analysis of ejector used in automotive power steering oil discharge equipment (EI CONFERENCE) 会议论文
2012 International Conference on Mechanical Engineering, Materials Science and Civil Engineering, ICMEMSCE 2012, August 18, 2012 - August 20, 2012, Harbin, China
Cheng K.; Zou H.; Kong X.; Tang J.
收藏  |  浏览/下载：17/0  |  提交时间：2013/03/25
Luminescence and energy transfer in Ca3Sc2Si 3O12:Ce3+,Mn2+ white LED phosphors (EI CONFERENCE) 会议论文
Liu Y.; Zhang X.; Hao Z.; Luo Y.; Wang X.; Ma L.; Zhang J.
收藏  |  浏览/下载：31/0  |  提交时间：2013/03/25
Design and implementation of a single actuated bio-mimetic robotic fish (EI CONFERENCE) 会议论文
2012 9th IEEE International Conference on Mechatronics and Automation, ICMA 2012, August 5, 2012 - August 8, 2012, Chengdu, China
Wan H.; Xu J.; Wang X.; Xu J.
收藏  |  浏览/下载：43/0  |  提交时间：2013/03/25

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