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H9N2 influenza virus in China： a cause of concern

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Protein & Cell 2015年第1期6卷 18-25页

作者： Yipeng sun jinhua Liu Key Laboratory of Animal Epidemiology and Zoonosis Ministry of Agriculture College of Veterinary MedicineChina Agricultural University Beijing 100083 China

The recent human infection with avian influenza virus revealed that H9N2 influenza virus is the gene donor for H7N9 and H10N8 viruses infecting humans. The crucial role of H9N2 viruses at the animal-human interface might be due to the wide host range, adaptation in both poultry and mammalian, and extensive gene reassortment. As the most prevalent subtype of influenza viruses in chickens in China, H9N2 also causes a great economic loss for the poultry industry, even under the long-term vaccination programs. The history, epidemiology, bio- logical characteristics, and molecular determinants of H9N2 influenza virus are reviewed in this paper. The contribution of H9N2 genes, especially RNP genes, to the infection of humans needs to be investigated in the future.

关键词： Influenza Poultry H9N2 Evolution,Virulence Antigenic drift

Thermal stability of LiPF_6/EC+DMC+EMC electrolyte for lithium ion batteries

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Rare Metals 2006年第Z1期25卷 94-99页

作者： WANG Qingsong sun jinhua CHEN Chunhua State Key Laboratory of Fire Science University of Science and Technology of China Hefei 230026 China State Key Laboratory of Fire Science University of Science and Technology of China Hefei 230026 China Department of Materials Science & Engineering University of Science and Technology of China Hefei 230026 China

The thermal stability of lithium-ion battery electrolyte could substantially affect the safety of lithium-ion battery. In order to disclose the thermal stability of 1.0 mol·L-1 LiPF6/ethylene carbonate (EC)+dimethyl carbonate (DMC)+ethylmethyl carbonate (EMC) electrolyte, a micro calorimeter C80 micro calorimeter was used in this paper. The electrolyte samples were heated in argon atmosphere, and the heat flow and pressure performances were detected. It is found that LiPF6 influences the thermal behavior remarkably, with more heat generation and lower onset temperature. LiPF6/EC shows an exothermic peak at 212 ℃ with a heat of reaction -355.4 J·g-1. DMC based LiPF6 solution shows two endothermic peak temperatures at 68.5 and 187 ℃ in argon filled vessel at elevated temperature. EMC based LiPF6 solution shows two endothermic peak temperatures at 191 and 258 ℃ in argon filled vessel. 1.0 mol·L-1 LiPF6/EC+DMC+ EMC electrolyte shows an endothermic and exothermic process one after the other at elevated temperature. By comparing with the thermal behavior of single solvent based LiPF6 solution, it can be speculated that LiPF6 may react with EC, DMC and EMC separately in 1.0 mol·L-1 LiPF6/EC+DMC+EMC electrolyte, but the exothermic peak is lower than that of 1.0 mol·L-1 LiPF6/EC solution. Furthermore, The 1.0 mol·L-1 LiPF6/EC+DMC+EMC electrolyte decomposition reaction order was calculated based on the pressure data, its value is n=1.83, and the pressure rate constants kp=6.49×10-2 kPa·-0.83·min-1.

关键词： lithium ion battery electrolyte thermal stability C80 micro calorimeter

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“麦稻连作”冬、春小麦选育品种对比试验

天津农林科技 2024年第2期 10-12页

作者：孙金华辛宇张春旭赵燕王兆福天津市静海区农业科学技术研究所天津301600

为提高耕地复种指数,探索适宜天津市静海区种植的“麦稻连作”冬春小麦品种,试验选用津强系列5个春小麦品种及炫麦88、沧麦6002等5个冬小麦品种,调查参试品种的生育期、茎蘖生长动态、穗部与籽粒性状、产量等。结果表明,春小麦津强7号... 详细信息

为提高耕地复种指数,探索适宜天津市静海区种植的“麦稻连作”冬春小麦品种,试验选用津强系列5个春小麦品种及炫麦88、沧麦6002等5个冬小麦品种,调查参试品种的生育期、茎蘖生长动态、穗部与籽粒性状、产量等。结果表明,春小麦津强7号生育期为78 d,在5个参试品种中生育期最短,综合性状及产量最高,较津强12号(CK)增产77.33%。冬小麦鑫瑞麦38生育期为235 d,在5个参试品种中生育期最短,综合性状及产量最高,较对照炫麦88(CK)增产35.62%。春小麦津强7号与冬小麦鑫瑞麦38均可作为天津市静海区“麦稻连作”种植模式的春小麦和冬小麦品种。

关键词：春小麦冬小麦品种筛选麦稻连作

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Can the Shanghai LNG Price Index indicate Chinese market?An econometric investigation using price discovery theory

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Frontiers in Energy 2020年第4期14卷 726-739页

作者： Yeli ZENG Cong DONG Mikael HOOK jinhua sun Danyang SHI School of Economics and Management China University of PetroleumBeijing 102249China School of International Trade and Economics University of International Business and EconomicsBeijing 100029China Department of Earth Sciences Uppsala UniversityUppsala 75105Sweden Crude Oil Department Petro China International Co.Ltd.Beijing 100033China

China became the world's second largest liquefied natural gas(LNG)importer in 2018 but has faced extremely high import costs due to a lack of bargaining *** of the Shanghai LNG Price Index,first released in 2015,are vital for improving the understanding of these cost *** paper,using the LNG price index data from the Shanghai Petroleum and Gas Exchange(SHPGX)coupled with domestic and international LNG prices from July 1,2015 to December 31,2018,estimates several econometric models to evaluate the long-term and short-term equilibriums of the Shanghai LNG Price Index,the responses to market information shocks and the leading or lagging relationships with LNG and alternative energy prices from other *** results show that the LNG price index of the SHPGX has already exhibited a long-term equilibrium and short-term adjustment mechanisms to reflect the average price level and market movements,but the market information transparency and price discovery efficiency of the index are still ***'s LNG market is still relatively independent of other natural gas markets,and marketization reforms are under way in *** influence of the SHPGX LNG price index on the trading decisions of market participants is expected to improve with further development of China's LNG reforms,the formation of a natural gas entry-exit system,and the increasing liquidity of the hub.

关键词： liquefied natural gas price index Shanghai Petroleum and Gas Exchange price discovery market reforms

Self-organized criticality judgment and extreme statistics analysis of major urban fires

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Chinese Science Bulletin 2011年第6期56卷 567-572页

作者： WANG JingHong XIE Shu sun jinhua State Key Laboratory of Fire Science University of Science and Technology of China Hefei 230026 China USTC-CityU Joint Advanced Research Centre Suzhou 215123 China Anhui General Fire Brigade Hefei 230026 China

The spatial (economic loss) and temporal characteristics of urban fires were analyzed employing relevant statistical methods. A fractal structure in terms of the power-law relation between fire frequency and economic loss was found on a spatial scale, and an exponential relation between frequency and time interval was found on a temporal scale. Thus, urban fire does not meet the rigorous criteria of self-organized criticality. In addition, based on the spatial power-law distribution characteristics, a correlation model of the frequency and scale of loss due to urban fire was established using the extremum statistical method. This model was then applied to the case analysis of Hefei and the probability of major fire incidents in the future was predicted.

关键词：自组织临界性城市火灾统计分析统计方法时空特征经济损失时间尺度相关模型

A reduced state SISO iterative decoding algorithm for serially concatenated continuous phase modulation

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Science in China(Series F) 2007年第4期50卷 539-550页

作者： sun jinhua LI JianDong JIN LiJun State Key Laboratory of Integrated Service Networks Xidian University Xi'an 710071 China

In this paper, serially concatenated continuous phase modulation （SCCPM） system is analyzed and a reduced state soft input soft output （SlSO） a posteriori probability algorithm is proposed. Based on the reduced state sequence detection （RSSD）, it has the more general form compared with other reduced state SISO algorithms. The proposed algorithm can greatly reduce the state number, thus leads to the computation complexity reduction. It also minimizes the degradation in Euclidean distance with decision feedback in the reduced state trellis. Analysis and simulation results show that the performance degradation is little with proper reduction scheme.

关键词： concatenated codes continuous phase modulation (CPM) soft input soft output (SISO) Euclidean distance

Experimental and LES investigation of flame propagation in a hydrogen/air mixture in a combustion vessel

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Chinese Science Bulletin 2014年第20期59卷 2496-2504页

作者： Huahua Xiao Zhanli Mao Weiguang An jinhua sun State Key Laboratory of Fire Science University of Science and Technology of China Department of Fire Protection Chinese People’s Armed Police Force Academy

This work presents an experimental and numerical investigation of premixed flame propagation in a hydrogen/air mixture in a closed combustion *** the experiment,high-speed schlieren video photography and pressure sensor are used to examine the flame dynamics and pressure *** the numerical study,a large eddy simulation(LES)based on a RNG sub-grid approach and a LES combustion model is applied to reproduce experimental *** effects of four physical phenomena on the burning velocity are considered in the combustion model,and the impact of grid type on the combustion dynamics is examined in the LES *** flame experiences four stages both in experiment and LES calculations with structured and unstructured grids,i.e.,spherical flame,finger-shaped flame,flame with its skirt in contact with the sidewalls,and tulip-shaped *** flame speed and pressure in the vessel develop with periodical oscillations in both the experiment and LES simulations due to the interaction of flame front with pressure *** numerical simulations compare well with the detailed experimental measurements,especially in term of the flame shape and position,pressure build-up,and periodical oscillation *** LES combustion model is successfully validated against the bench-scale *** is put into evidence that mesh type has an impact to a certain extent on the numerical combustion dynamics,and the LES calculation on structured grid canpredict the flame dynamics and pressure rise more accurately than that on unstructured grid with the same mesh *** flame shape is more asymmetrical in the LES on an unstructured grid than that on a structured grid,and both the flame speed and the pressure rise at the later flame stage are underestimated in the LES on the unstructured grid.

关键词：火焰传播实验测量空气混合物燃烧器 Les 非结构化网格燃烧动力学数值模拟

Transition-metal redox evolution and its effect on thermal stability of LiNixCoyMnzO_(2) based on synchrotron soft X-ray absorption spectroscopy

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Journal of Energy Chemistry 2021年第8期30卷 446-454,I0010页

作者： Chen Liang Wenhua Zhang Zesen Wei Zhaoyu Wang Qingsong Wang jinhua sun State Key Laboratory of Fire Science University of Science and Technology of ChinaHefei 230026China National Synchrontron Radiation Laboratory University of Science and Technology of ChinaHefei 230026China

Based on the synchrotron soft X-ray absorption spectroscopy experiments,the fundamental electronic structures of layered Li NixCoyMnzO_(2)(NCM)are investigated systematically and the data of transitionmetal(TM)L-and O K-edges spectra are *** of Ni ions under different oxidation states is evaluated according to linear combination *** is found that the ratio of Ni^(4+)expands with the increase of Ni since it dominates in charge compensation during charging,and that the existence of Ni^(3+)is nearly negligible in delithiated *** valence state of Co also strongly depends on Ni content,the perceptible position shift of Co L_(3)-edge absorption peak towards higher energy in Ni-rich material agrees well with the small voltage plateau at around 4.2 *** stability of Mn is verified as no obvious spectral change with the Mn L-edge is ***,as Ni content rises,the O 2p holes near the Femi level increases with higher oxidation state of Ni,indicating the enhanced hybridization of O 2p-TM 3 *** NCMs with higher Ni content are prior to lose electron existing in highly hybridized Ni3 dO 2 p bands upon heating,which accounts for the pronounced O_(2)release in phase transitions and the deterioration in thermal *** detailed observation of the electronic structure evolution is one of the key ingredients to improving the electrochemical and thermal performance of NCM.

关键词： Lithium ion battery safety Cathode material Soft X-ray absorption spectroscopy Thermal stability

Inhibiting effect of Al(OH)_3 and Mg(OH)_2 dust on the explosions of methane-air mixtures in closed vessel

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Science China(Technological Sciences) 2012年第5期55卷 1371-1375页

作者： WANG QiuHong WEN Hu WANG QingSong sun jinhua State Key Laboratory of Fire Seience University of Science and Technology of ChinaHeJei 230026China School of Energy Engineering Xi'an University of Science and TechnologyXi'an 710054China

The inhibiting effect of Al(OH)3 and Mg(OH)2 dust on explosion of methane-air mixtures was investigated by means of explosion parameter tests in a 20-liter closed vessel. The influences of varying methane concentration and dust concentration on explosion parameters were characterized based on the experimental data to determine the maximum explosion pressure, maximum rate of pressure rise, lower explosion limits and upper explosion limits. The inhibiting mechanisms of these kinds of dust were analyzed as well. The investigations indicate that Al(OH)3 and Mg(OH)2 dust can be used as inhibitors to prevent meth- ane explosion, however, their inhibiting effects are less than those of inert gas such as N2 and CO2 in that their dust can weaken the methane explosion but cannot totally eliminate it. The tests show that all of the explosion parameters with dust additives are strongly dependent on methane/air ratio and dust concentration, and Al(OH)3 dust has better performance than Mg(OH)2 dust in inhibiting methane explosion. The average percentage decreases of maximum explosion pressure and maximum rate of pressure rise with Al(OH)3 dust are 11.08% and 66.15%, respectively. Experiments also showed that there is a special phenomenon when methane explosion is inhibited by Al(OH)3 and Mg(OH)2 dust, in which is that during the process of explosion the maximum explosion pressure value first decreases then increases as dust concentration increases. The best dust concentra- tions to inhibit the explosion are 250 g/m3 with methane/air ratio at 9.5%, and 200 g/m3 with methane/air ratio at 7%. It is suggested that water vapor produced by the thermal decomposition of metal hydroxides makes the particles of descending dust combine, resulting in a decrease of the real dust concentration in the vessel. Water vapor also is the major cause of another phenomenon that the LEL curve and the UEL curve never meet with the increase of gas concentration.

关键词： MG(OH)2 空气混合物爆炸参数甲烷浓度密闭容器灰尘 AI 抑制效果