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Petroleum Science 2023年第2期20卷 827-839页

作者： xi-jun he Jing-Shuang Li Xue-Yuan Huang Yan-Jie Zhou School of Mathematics and Statistics Beijing Technology and Business University(BTBU)Beijing100048China School of Science China University of Mining and Technology(Beijing)Beijing100083China

Accurate wave propagation simulation in anisotropic media is important for forward modeling, migration and inversion. In this study, the weighted Runge-Kutta discontinuous Galerkin (RKDG) method is extended to solve the elastic wave equations in 2D transversely isotropic media. The spatial discretization is based on the numerical flux discontinuous Galerkin scheme. An explicit weighted two-step iterative Runge-Kutta method is used as time-stepping algorithm. The weighted RKDG method has good flexibility and applicability of dealing with undulating geometries and boundary conditions. To verify the correctness and effectiveness of this method, several numerical examples are presented for elastic wave propagations in vertical transversely isotropic and tilted transversely isotropic media. The results show that the weighted RKDG method is promising for solving wave propagation problems in complex anisotropic medium.

关键词： Discontinuous Galerkin method Anisotropy Transversely isotropic Modeling

Mechanistic insight into the synergy between nickel single atoms and nanoparticles on N-doped carbon for electroreduction of CO2

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Journal of Energy Chemistry 2025年第1期100卷 327-336页

作者： Mingdong Sun Wenwen Guan Cailing Chen Chao Wu xiaoling Liu Biao Meng Tao Chen Yu Han jun Wang Shibo xi Yu Zhou State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical Engineering Nanjing Tech University Advanced Membranes and Porous Materials Center Physical Sciences and Engineering Division King Abdullah University of Science and Technology Institute of Sustainability for Chemicals Energy and Environment A*STAR (Agency for Science Technology and Research) College of Materials Science and Engineering Sichuan University

The synergy of single atoms （SAs） and nanoparticles （NPs） has demonstrated great potential in promoting the electrocatalytic carbon dioxide reduction reaction （CO2RR）;however,the rationalization of the SAs/NPs proportion remains one challenge for the catalyst ***,a Ni2+-loaded porous poly（ionic liquids）(PIL) precursor synthesized through the free radical self-polymerization of the ionic liquid monomer,1-allyl-3-vinylimidazolium chloride,was pyrolyzed to prepare the Ni,N co-doped carbon materials,in which the proportion of Ni SAs and NPs could be facilely modulated by controlling the annealing *** catalyst Ni-NC-1000 with a moderate proportion of Ni SAs and NPs exhibited high efficiency in the electrocatalytic conversion of CO2into *** Ni K-edge X-ray absorption near-edge structure （XANES） spectra and theoretical calculations were conducted to gain insight into the synergy of Ni SAs and *** charge transfer from Ni NPs to the surrounding carbon layer and then to the Ni SAs resulted in the electron-enriched Ni SAs active *** the electroreduction of CO2,the coexistence of Ni SAs and NPs strengthened the CO2activation and the affinity towards the key intermediate of*COOH,lowering the free energy for the potential-determining*CO2→*COOH step,and therefore promoted the catalysis efficiency.

关键词： Single atom catalyst Synergy effect Carbon catalyst Electrocatalysis

Efficacy evaluation of the C-strain-based vaccines against the subgenotype 2.1d classical swine fever virus emerging in China

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Efficacy evaluation of the C-strain-based vaccines against t...

大豆致敏原β-伴大豆球蛋白α’亚基的分段与克隆鉴定

中国畜牧兽医学会动物传染病学分会第九次全国会员代表大会暨第十七次全国学术研讨会

作者：罗玉子 Shengwei Ji Jian-Lin Lei Guang-Tao xiang xing-Yu Meng Guanglai Zheng Yimin Wang Yongfeng Li Su Li xi-jun he Yuan Sun Hua-Ji Qiu State Key Laboratory of Veterinary Biotechnology Harbin Veterinary Research InstituteChinese Academy of Agricultural Sciences

Classical swine fever(CSF) is a devastating infectious disease of pigs caused by classical swi ne fever virus(CSFV).The disease has been controlled following extensive vaccination with the 1 apinized attenuated vaccine C-strain for decades in ***,frequent CSF outbreaks occurr ed recently in a large number of C-strain-vaccinated pig farms in China and a new subgenotype 2.1 d of CSFV has been reported to be responsible for the *** we analyzed the molecul ar variations and antigenic differences among the C-strain-based commercial vaccines of different o rigins from different manufacturers in China,and reevaluated the vaccines against the emerging su bgenotype 2.1 d strain of *** results showed that the C-strain adapted to the continuous ST cell line(C) contain a unique M290 K variation on the E2 protein,compared to those of prima ry BT cells(C) or rabbit origin(C) and the traditional C-strain sequences available in the Ge nBank *** neutralization test revealed the antigenic differences between Cst and Cbt or ***,the neutralizing titers of porcine anti-C-strain sera against the CSFV isolate of su bgenotype 2.1 d were significantly lower than those against C-strain or Shimen *** C-strainvaccinated,subgenotype 2.1 d HLJZZ2014 strain-challenged pigs did not show any clinical signs an d all ***,these pigs displayed mild pathological and histological lesions,and the C SFV viral RNA was detected in the various tissue and blood *** together,the C-strain-based vaccines of different origins showed molecular variations and antigenic differences,and cou1 d provide clinical but not pathological and virological protection against the subgenotype 2.1 d CS FV emerging in *** investigation is needed to comprehensively assess the efficacy of C-strain of different doses against the subgenotype 2.1 d CSFV.

关键词： Classical swine fever virus Subgenotype 2.1d C-strain vaccines Efficacy

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食品科技 2018年第3期43卷 25-28页

作者：李爽席俊贺梦雪皮江一于秋荣河南工业大学粮油食品学院郑州450001

大豆是引起人们食物过敏的八大过敏原之一,β-伴大豆球蛋白是大豆主要致敏蛋白之一,并且3个亚基α、α’、β都具有致敏性。利用生物信息学软件对β-伴大豆球蛋白α’亚基进行Overlapping(重叠)分段,通过PCR技术扩增到目的片段,与pMD 1... 详细信息

大豆是引起人们食物过敏的八大过敏原之一,β-伴大豆球蛋白是大豆主要致敏蛋白之一,并且3个亚基α、α’、β都具有致敏性。利用生物信息学软件对β-伴大豆球蛋白α’亚基进行Overlapping(重叠)分段,通过PCR技术扩增到目的片段,与pMD 18-T载体连接;对重组质粒进行PCR和双酶切鉴定,鉴定结果与基因序列一致,成功构建克隆载体。

关键词： α’亚基分段克隆

A survey on orbital dynamics and navigation of asteroid missions

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Acta Mechanica Sinica 2014年第3期30卷 282-293页

作者： he-xi Baoyin jun-Feng Li School of Aerospace Tsinghua University

Asteroid exploration is currently one of the most concerned topics among international space agencies. Or- bital dynamics and navigation are obviously crucial for asteroid exploration. This paper aims to give a brief review on the dynamics, control and navigation of asteroid reconnaissance orbits, including the heliocentric transfer orbit and near as- teroid orbit. The developments in optimization techniques of the transfer segment are discussed in detail. We surveyed global researches in this field and made comments on several important progresses. The final section proposed a prospec- tive of future studies with emphasis on the key techniques of these issues in the asteroid exploration missions.

关键词： Asteroid Orbital dynamics Navigation Control Guidance

Enhanced power saving mechanism for supporting multicast services in 802.11 wireless LANs

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第6期10卷 828-833页

作者： Yong he Rui-xi YUAN xiao-jun MA jun LI Center for Intelligent & Networked Systems Tsinghua University Beijing 100084 China Thomson Broadband R&D Co. Ltd Beijing 100085 China

Traditional 802.11 power saving mechanism (PSM) treats multicast and broadcast traffic equally, and suffers sig-nificant performance degradation with multicast background traffic. This paper proposes an enhanced PSM that effectively dif-ferentiates multicast streams. It re-arranges the virtual bitmap of the traffic indication map (TIM) to carry traffic status for mul-ticast groups and introduces a concept of sequential transmission of multi-addressed data to facilitate differentiation among mul-ticast groups. Our analysis shows that the enhanced PSM can effectively save power in mixed traffic environments.

关键词： 802.11 Wireless network Power saving Multicast services

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中国铁皮石斛白绢病的研究

西部林业科学 2017年第3期46卷 89-95页

作者：席刚俊杨鹤同赵楠史俊徐超赵桂华江苏农林职业技术学院江苏句容212400

为了研究铁皮石斛白绢病,于2013年4月至2015年7月,在室内外对病害危害程度、症状、病原菌分离、鉴定、致病性试验、发病规律及防治方法进行观察和研究。结果表明,铁皮石斛白绢病可为害叶片、茎秆和根部,后期致植株死亡,产生许多菌核。... 详细信息

为了研究铁皮石斛白绢病,于2013年4月至2015年7月,在室内外对病害危害程度、症状、病原菌分离、鉴定、致病性试验、发病规律及防治方法进行观察和研究。结果表明,铁皮石斛白绢病可为害叶片、茎秆和根部,后期致植株死亡,产生许多菌核。叶片和茎秆上的病原菌分离得率均在80%以上。通过形态描述、DNA分子测序和致病性试验,确定翠雀小核菌是引起铁皮石斛死亡的病原菌,接种8周后,可引起植株死亡,症状与自然发病相似。在病害发生之前或发生初期应选用哈茨木霉、枯草芽孢杆菌制剂进行预防。病害发生后,使用多菌灵防治。这是一种毁灭性病害,在国内首次对该病害进行全面报道。

关键词：铁皮石斛白绢病病原菌发生规律防治

Sensitivity analysis for a type of statically stable sailcrafts

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Acta Mechanica Sinica 2012年第2期28卷 532-542页

作者： Zheng-Xue Li jun-Feng Li he-xi Baoyin School of Aerospace Tsinghua University100084 BeijingChina

Two types of sensitivities are proposed for stat- ically stable sailcrafts. One type is the sensitivities of solar-radiation-pressure force with respect to position of the center of mass, and the other type is the sensitivities of solar-radiation-pressure force with respect to attitude. The two types of sensitivities represent how the solar-radiation- pressure force changes with the position of mass center and the attitude. Sailcrafts with larger sensitivities undergo larger error of the solar-radiation-pressure force, leading to larger orbit error, as demonstrated by simulation. Then as a case study, detailed formulas are derived to calculate the sensi- tivities for sailcrafts with four triangular sails. According to these formulas, in order to reduce both types of sensitivities, the angle between opposed sails should not be too large, and the center of mass should be as close to the axis of symmetry of the four sails as possible and as far away from the center of pressure of the sailcraft as possible.

关键词： Statically stable sailcraft Sensitivity Solar- radiation-pressure force error. Mass center and pressure cen- ter errors Attitude and orbit errors

Dependence of Dilepton Production in the Baryon-Rich Quark-Gluon Fireball on the Initial Temperature

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Chinese Physics Letters 1997年第1期14卷 24-27页

作者： he Ze-jun ZHANG Jia-ju QIU xi-jun CCAST(World Laboratory) P.O.Box 8730Beijing 100080 Institute of Nuclear Research Chinese Academy of SciencesShanghai 201800

In the study of dilepton production of a baryon-rich quark-gluon fireball based on the full stopping scenario via a relativistic hydrodynamic model,it is found that for the fixed initial baryon chemical potential with increasing initial temperature a peak indicating the formation of the baryon-rich quark-gluon matter appears in the total dilepton yield.

关键词： quark lepton relativistic

Modified sewage sludge as temporary landfill cover material

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Water Science and Engineering 2015年第3期8卷 257-262页

作者： jun he Feng Li Yong Li xi-lin Cui College of Civil and Architectural Engineering Hubei University of Technology

In order to study the feasibility of modified sewage sludge as landfill cover material and its performance in a complex landfill environment, strength and hydraulic conductivity tests were conducted. The permeability requirements for daily and interim covers were analyzed first. Based on saturated-unsaturated seepage calculations, it is suggested that approximately 1.0×10^-4 cm/s and 1.0 × 10^-5 cm/s are the appropriate values for the hydraulic conductivities of daily and interim covers, respectively. The strength and permeability requirements of the mixtures, when used as an interim cover, can be met at a sludge：lime：cement：silt：tire-derived aggregate （TDA） weight ratio of 100：15：5：70：15. Results also demonstrate that the solid content ratio of modified sewage sludge, which should be greater than 60% when modified sewage sludge is used as a temporary cover material, is crucial to both strength and hydraulic performance. In addition, as the duration of soaking of modified sewage sludge in synthetic leachate increases, the unconfined compressive strength increases, and the hydraulic conductivity decreases slightly or fluctuates between 1.0×10^-5 cm/s and 1.0 × 10^-6 cm/s, still meeting the requirements for an interim cover. The reduction in hydraulic conductivity of modified sewage sludge under the effect of synthetic leachate, as well as the long-term and environmental performance of the modified sewage sludge, should be examined in future studies.

关键词： Modified sewage sludge Temporary cover Hydraulic conductivity Unconfined compressive strength Soaking