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Measuring the beaming angle of GRB 030329 by fitting the rebrightenings in its multiband afterglow

Research in Astronomy and Astrophysics 2010年第11期10卷 1119-1126页

作者： wei Deng Yong-Feng Huang si-wei kong Department of Astronomy Nanjing University Nanjing 210093 China Key Laboratory of Modern Astronomy and Astrophysics （Nanjing Univ.） Ministry of EducationNanjing 210093 China

Multiple rebrightenings have been observed in the multiband afterglow of GRB 030329. In particular, a marked and quick rebrightening occurred at about t 1.2 × 10^5 s. Energy injection from late and slow shells seems to be the best interpretation for these rebrightenings. Usually it is assumed that the energy is injected into the whole external shock. However, in the case of GRB 030329, the rebrightenings are so quick that the usual consideration fails to give a satisfactory fit to the observed light curves. Actually, since these late/slow shells freely coast in the wake of the external shock, they should be cold and may not expand laterally. The energy injection then should only occur at the central region of the external shock. Considering this effect, we numerically re-fit the quick rebrightenings observed in GRB 030329. By doing this, we were able to derive the beaming angle of the energy injection process. Our result, with a relative residual of only 5% - 10% during the major rebrightening, is bet- ter than any previous modeling. The derived energy injection angle is about 0.035. We assume that these late shells are ejected by the central engine via the same mechanism as those early shells that produce the prompt gamma-ray burst. The main difference is that their velocities are much slower, so that they catch up with the external shock relatively late and are manifested as the observed quick rebrightenings. If this were true, then the derived energy injection angle can give a good measure of the beaming angle of the prompt γ-ray emission. Our study may hopefully provide a novel method to measure the beaming angle of gamma-ray bursts.

关键词： gamma-rays bursts-ISM jets and outflows

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Ring-Shaped Jets in Gamma-Ray Bursts

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Chinese Journal of Astronomy and Astrophysics 2008年第4期8卷 411-420页

作者： Ming Xu Yong-Feng Huang si-wei kong Department of Astronomy Nanjing University Nanjing 210093 China

When the axis of a gamma-ray burst （GRB） does not coincide with the spin axis of its source, there may result a ring-shaped jet. Using some refined jet dynamics, we calculate multi-wavelength afterglow light curves for such ring-shaped jets. In the R-band we find an obvious break in the afterglow light curve due to the beaming effect and the break is affected by many parameters, such as the electron energy fraction ζe, the magnetic energy fraction ζB^2, the width of ring △θ and the medium number density n. The overall light curve can be divided into three power-law stages, i.e., an ultra-relativistic stage, an after-break stage and a deep Newtonian stage. For each stage the power-law index is larger in the ring-shaped jet than in the corresponding conical jet.

关键词： gamma rays bursts - ISM jets and outflows

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Detecting radio afterglows of gamma-ray bursts with FAST

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Research in Astronomy and Astrophysics 2015年第2期15卷 237-251页

作者： Zhi-Bin Zhang si-wei kong Yong-Feng Huang Di Li Long-Biao Li Department of Physics College of Sciences Guizhou University Key Laboratory for Particle Astrophysics Institute of High Energy Physics Chinese Academy of Sciences Department of Astronomy Nanjing University National Astronomical Observatories Chinese Academy of Sciences

Using the generic hydrodynamic model of gamma-ray burst （GRB） after- glows, we calculate the radio afterglow light curves of low luminosity, high luminosity, failed and standard GRBs in different observational bands of FAST＇s energy window. The GRBs are assumed to be located at different distances from us. Our results rank the detectability of GRBs in descending order as high luminosity, standard, failed and low luminosity GRBs. We predict that almost all types of radio afterglows except those of low luminosity GRBs could be observed by a large radio telescope as long as the domains of time and frequency are appropriate. It is important to note that FAST can detect relatively weak radio afterglows at a higher frequency of 2.5 GHz for very high redshift up to z = 15 or even more. Radio afterglows of low luminosity GRBs can only be detected after the completion of the second phase of FAST. FAST is expected to significantly expand the sample of GRB radio afterglows in the near future.

关键词： gamma rays: bursts methods: numerical telescopes

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A low redox potential and long life organic anode material for sodium-ion batteries

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Journal of Energy Chemistry 2025年第1期100卷 557-564页

作者： Zhi Li Yang wei Kang Zhou Xin Huang Xing Zhou Jie Xu Taoyi kong Junwei Lucas Bao Xiaoli Dong Yonggang Wang Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials Institute of New Energy Collaborative Innovation Center of Chemistry for Energy Materials (iChEM) Fudan University Department of Chemistry Boston College School of Materials Science and Engineering Anhui University of Technology

Sodium-ion batteries （siBs） with organic electrodes are an emerging research direction due to the sustainability of organic materials based on elements like C,H,O,and sodium ***,organic electrode materials for siBs are mainly used as cathodes because of their relatively high redox potentials（>1 V）.Organic electrodes with low redox potential that can be used as anode are ***,a novel organic anode material （tetrasodium 1,4,5,8-naphthalenetetracarboxylate,Na4TDC） has been developed with low redox potential （situ/ex-situ spectroscopy and theoretical calculations,showing a high capacity of 208 mAh/g and an average decay rate of merely 0.022%per ***,the Na4TDC-hard carbon composite can further acquire improved capacity and cycling stability for 1200 cycles even with a high mass loading of up to 20 mg *** pairing with a thick Na3V2（PO4）3cathode (20.6 mg cm-2),the as-fabricated full cell exhibited high operating voltage （2.8 V）,excellent rate performance and cycling stability with a high capacity retention of 88.7% after 200 cycles,well highlighting the Na4TDC anode material for siBs.

关键词： Organic anode material Low redox potential Composite anode Sodium-ion batteries

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Micro-strain regulation strategy to stabilize perovskite lattice based on the categories and impact of strain on perovskite solar cells

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Journal of Energy Chemistry 2025年第1期100卷 578-604页

作者： Caixia Li Wenwu Liu Shiji Da Lingbin kong Fen Ran State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of Technology School of Materials Science and Engineering Lanzhou University of Technology

Photovoltaic metal halide perovskite solar cells(PSCs) convert light to electricity more efficiently than crystalline silicon cells, and the cost of materials used to make them is lower than that of silicon *** efficiency is not a core issue affecting the application of perovskite solar cells in special *** present, stability is the major technical encounters that hinders its further commercial development. Microstrain in PSCs is currently a significant factor responsible for the device's instability. Strain-induced ion migration is widely believed to accelerate perovskite degradation even when external stimuli are ***, it is imperative to study strain to enhance the stability of PSCs. This paper reviews recent developments to understand strain's origin and effect mechanisms on performance of PSCs, including ion migration,failure behavior, defect formation, and its effect on photoelectric properties, stability, and ***, several well-known strain management strategies are systematically introduced based on the strain effect mechanism and strain engineering on the film, providing more clues for further preparation with increased stability. The manipulation of external physical strain applied from films to entire devices has been extensively studied. Furthermore, recommendations for future research directions and chemical approaches have been provided. It is emphasized that strain engineering plays a crucial role in improving the efficiency and longevity of PSCs. Tensile strain causes rapid degradation, while moderate compressive strain and external strain control could improve properties and stability. Efforts should focus on controlling compressive strain to mitigate residual tensile strain and introducing it in a controlled manner. Future research endeavors may focus on exploring these pathways to improve the efficiency and lifespan of PSCs.

关键词： Halide perovskite solar cells Strain origins Strain effects Strain management

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The School that Changes Mindsets

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China Today 2025年第1期74卷 62-64页

作者： GUO QING kong siQI 不详

China’s highest-altitude primary school is not only teaching children of farmers and herders but their parents as *** sinopec Primary School in Nagqu,a city in Xizang Autonomous Region in southwest China,is known as the school“the closest to the sky”due to its high-altitude location-a breathtaking 4,700 meters above sea *** by oil and gas giant sinopec as part of its corporate social responsibility,the school opened in 2012 and has since become a microcosm of China’s drive for education,especially in remote and rural areas,to ensure that no one is left behind.

关键词： altitude farmers southwest

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Long duplication of 18S ribosomal DNA in Cynoglossus lineolatus(Pleuronectiformes： Cynoglossidae)： novel molecular evidencefor unequal crossing over model

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Acta Oceanologica sinica 2016年第12期35卷 38-50页

作者： GONG Li SHI wei YANG Min si Lizhen kong Xiaoyu Guangxi Key Laboratory of Mangrove Conservation and Utilization Guangxi Mangrove Research Center Guangxi Academy of Sciences Beihai 536000 China Key Laboratory of Tropical Marine Bio-resources and Ecology/Guangdong Provincial Key Laboratory of Applied Marine Biology South China Sea Institute of Oceanology Chinese Academy of Sciences Guangzhou 510000 China University of the Chinese Academy of Sciences Beijing 100049 China

Although 18 S r DNA sequence is extremely conservative, the polymorphism still has been found in few *** the present study, three types(Type A, B and C) of 18 S r DNA sequence coexisted in Cynoglossus lineolatus genome, suggesting a non-concerted evolution process, rather than a strictly concerted evolution *** on the differences of sequence variation, GC content, secondary structure and minimum free energy,Types A and B were speculated as the potential pseudogenes. Additionally, a fascinating finding was a 189-bp duplication of 18 S r DNA in Type A sequence. To our knowledge, this is the first report on such a long duplication in teleostean ribosomal DNA. Compared with several theories accounting for the formation of tandem repeats, the unequal crossing over model was thought to be the most likely mechanism to generate the189-bp duplication of 18 S r DNA. These results not only provide a novel molecular evidence for the unequal crossing over model, but also benefit for the further study on 18 S r DNA in fishes.

关键词： nrDNA Cynoglossus lineolatus tandem repeat pseudogene polymorphism non-concerted evolution

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A stable Co(Ⅱ)-based metal-organic framework with dual-functional pyrazolate-carboxylate ligand:Construction and CO_(2) selective adsorption and fixation

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Chinese Chemical Letters 2021年第2期32卷 918-922页

作者： Guangrui si Xiangjing kong Tao He wei Wu Linhua Xie Jianrong Li Beijing Key Laboratory for Green Catalysis and Separation and Department of Environmental Chemical Engineering Beijing University of TechnologyBeijing 100124China

By taking the functional adva ntages of both pyrazolate and carboxylate ligands,a unique dual-functional pyrazolate-carboxylate ligand acid,4-(3,6-di(pyrazol-4-yl)-9-carbazol-9-yl)benzoic acid(H3PCBA) was designed and *** it,a new Co(Ⅱ)-based metal-organic framework(MOF),Co_(3)(PCBA)_(2)(H_(2)O)_(2)(BUT-75) has been *** revealed a(3,6)-connected net based on the 6-connected linear trinuclear metal node,and showed good chemical stability in a wide pH range from 3 to 12 at room temperature,as well as in boiling *** to the presence of rich exposed Co(Ⅱ) sites in pores,BUT-75 presented high selective CO_(2) adsorption capacity over N2 at 298 ***,it demonstrated fine catalytic performance for the cycloaddition of CO_(2) with epoxides into cyclic carbonates under ambient *** work has not only enriched the MOF community through integrating diverse functio nalities into one ligand but also contributed a versatile platform for CO_(2) fixation,thereby pushing MOF chemistry forward by stability enhancement and application expansion.

关键词： Metal-organic framework(MOF) Pyrazolate-carboxylate ligand Construction CO_(2)selective adsorption CO_(2)fixation

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Etoposide Induces Mitochondria-Associated Apoptotic Cell Death in Human Gastric Carcinoma Cells

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Chemical Research in Chinese Universities 2008年第5期24卷 597-602页

作者： LI Jing-hua CHEN Yue WANG Jia-si kong wei JIN Ying-hua Key Laboratory for Molecular Enzymology and Engineering Ministry of Education College of Life Science School of Public Health Jilin University Changchun 130012 P R. China

Recent observations indicate that the resistance of apoptosis is an important process of tumor metastasis and metastases are the cause of 90% of human cancer death. Etoposide, a semisynthetic derivative of the podophyllotoxins, is a clinically used anti-cancer reagent, but the effects of it on metastatic gastric carcinoma cells are totally unknown. In this study, etoposide induced apoptotic cell death in human gastric adenocarcinoma cell line SGC-7901, derived from metastatic lymph nodes, as evidenced by the analysis of DNA fragmentation, apoptotic body formation, caspase activation, and apoptosis specific changes in cell morphology is demonstrated. The depolarization of mitochondrial membrane and the release of cytochrome c were most early events in etoposide treated SGC-7901 cells, and were followed by caspase-3 activation and PARP cleavage. Caspase-8 activation was not detected under the same condition. Thus, it was proposed that etoposide induces caspase-associated apoptotic cell death in human metastatic gastric carcinoma, which is initiated by mitochondrial cytochrome c release.

关键词： Apoptosis Caspase Cytochrome c Etoposide SGC-7901 cells

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Global instability of Stokes layer for whole wave numbers

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Applied Mathematics and Mechanics(English Edition) 2016年第8期37卷 999-1012页

作者： wei kong Jisheng LUO Department of Mechanics Tianjin University

The study on the global instability of a Stokes layer, which is a typical unsteady flow, is usually a paradigm for understanding the instability and transition of unsteady flows. Previous studies suggest that the neutral curve of the global instability obtained by the Floquet theory is only mapped out in a limited range of wave numbers （0.2 ≤ a ≤ 0.5）. In this paper, the global instability is investigated with numerical simulations for all wave numbers. It is revealed that the peak of the disturbances displays irregularity rather than the periodic evolution while the wave number is beyond the above range. A ＂neutral point＂ is redefined, and a neutral curve of the global instability is presented for the whole wave numbers with this new definition. This work provides a deeper understanding of the global instability of unsteady flows.

关键词： Stokes layer instantaneous instability Floquet theory neutral curve

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