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Matching Boundary Conditions for Scalar Waves in Body-Centered-Cubic Lattices

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Advances in Applied Mathematics and Mechanics 2013年第3期5卷 337-350页

作者： ming fang Xianming Wang Zhihui Li Shaoqiang Tang Hypervelocity Aerodynamics Institute China Aerodynamics Research and Development CenterP.O.Box 211Mianyang 621000SichuanChina HEDPS CAPT and LTCSCollege of EngineeringPeking UniversityBeijing 100871China Center for Combustion Energy and Department of Thermal Engineering Tsinghua UniversityBeijing 100084China

Matching boundary conditions(MBC’s)are proposed to treat scalar waves in the body-centered-cubic *** matching the dispersion relation,we construct MBC’s for normal incidence and incidence with an angle *** of MBC operators then leads to multi-directional absorbing boundary *** effectiveness are illustrated by the reflection coefficient analysis and wave packet *** particular,the designed M1M1 treats the scalar waves in a satisfactory manner.

关键词： Body-centered-cubic(BCC)crystalline solids dispersion relation matching boundary condition reflection coefficient scalar waves

黑水虻幼虫中肠区块化免疫表达促进特征肠道微生物群落形成

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环境昆虫学报 2024年第5期46卷 1104-1112页

作者：韩璐滢项方铭孙佳杰刘乘源张志剑浙江大学环境与资源学院杭州310058 杭州行也生物科技有限公司杭州310058

黑水虻Hermetia illucens L.幼虫肠道中的免疫系统既需要消灭病原体,又要创造有益环境,保留共生微生物。Toll和免疫缺陷(Immune deficiency,Imd)通路是昆虫肠道内抵御病原体的基本免疫防御机制,然而黑水虻幼虫肠道中耐受共生菌的机制尚... 详细信息

黑水虻Hermetia illucens L.幼虫肠道中的免疫系统既需要消灭病原体,又要创造有益环境,保留共生微生物。Toll和免疫缺陷(Immune deficiency,Imd)通路是昆虫肠道内抵御病原体的基本免疫防御机制,然而黑水虻幼虫肠道中耐受共生菌的机制尚不清楚。本研究通过对比不同废弃物(餐厨垃圾、豆渣和鸡粪)中黑水虻幼虫中肠微生物组,发现放线菌门Actinobacteria、厚壁菌门Firmicutes、拟杆菌门Bacteroidetes和变形菌门Proteobacteria在肠道中占主导,并且肠道能富集放线菌门和拟杆菌门。通过随机森林模型预测,异单胞菌Dysgonomonas、摩氏摩根菌属Morganella、厌氧球菌属Anaerococcus最有可能是中肠中的特征菌属,这些菌的存在可能对黑水虻的生长有着重要影响并且可以作为判定样品是否属于黑水虻的标准。进一步研究表明后中肠的微生物负荷平均是前中肠和中中肠的8.56倍,同时异单胞菌主要在后中肠富集。另外,前中肠和中中肠的抗菌肽表达分别是后中肠的1645倍和10.20倍,而负反馈因子在后中肠的表达平均提高了4.66倍。本研究初步表明黑水虻幼虫肠道可能对微生物具有重塑作用,幼虫在前中肠通过抗菌肽筛选微生物,并在后中肠抑制抗菌肽释放保存共生菌。综上,本研究揭示了黑水虻幼虫肠道免疫的区域化表达可维持抗病原体能力的同时为共生微生物群构建保护区域的“先清除-后招募”机制。

关键词：黑水虻肠道微生物抗菌肽免疫通路

Transparent Co_(3)FeO_(x) Film Passivated BiVO_(4) Photoanode for Efficient Photoelectrochemical Water Splitting

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Chinese Journal of Structural Chemistry 2021年第11期40卷 1505-1512,1409页

作者： fang ming QIN Qi CAI Qian LIU Wei Fujian Normal University Fuzhou 350007China CAS Key Laboratory of Design and Assembly of Functional Nanostructures Fujian Provincial Key Laboratory of NanomaterialFujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

Photoelectrochemistry that use semiconductors to absorb sunlight for water splitting provides an effective method for the development of renewable hydrogen energy in the *** this paper,a transparent and highly-efficient cobalt-iron oxide(Co_(3)FeO_(x))nano-film was fabricated through hydrothermal method by directional adjustment of atomic ratio to promote the kinetics of BiVO_(4)(BVO)photoanode water *** a result,the Co_(3)FeO_(x)-modified BVO photoanode(Co_(3)FeO_(x)/BVO)exhibits an impressive photocurrent density of 4.0 mA·cm^(2) at 1.23 V versus reversible hydrogen electrode(RHE),approximately 2.17-fold higher than that of bare BVO,as well as a cathodically shifted onset potential of 320 *** catalyst nanolayer structure is clarified by ultraviolet-visible *** addition,the Co_(3)FeO_(x)/BVO photoanode has better stability,and there is no obvious activity degradation after 10 hours of *** strategy provides a broad prospect for the use of water oxidation co-catalyst to achieve effective water splitting.

关键词： photoelectrochemical water splitting bismuth vanadate co-catalyst cobalt-iron oxide

NUMERICAL SIMULATION OF 2D HORIZONTAL COOLING WATER DISCHARGE IN GENERALIZED CURVILINEAR COORDINATE

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Journal of Hydrodynamics 2006年第1期18卷 91-96页

作者： XIE Zuo-tao ZHANG Xiao-feng TAN Guang-ming YANG fang-li State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan UniversityWuhan 430072 China

2D horizontal model is one of the major mathematical methods for the research on cooling water discharge from the power plant. In this paper, the shallow water equations are transformed under the generalized curvilinear coordinate system and the elliptic differential equations are used to generate curvilinear grids, so a model in generalized curviline ar coordinate is presented to simulate 2D horizontal cooling water, Governing equations of the model are discretized by finite volume method, and non-staggered grids and SIMPLE algorithm are introduced to simplify the program during the discretization. This model is used to simulate the movement of cooling water in a simplified meandering channel and a natural channel, calculating results indicate this model can correctly reflect the movement rules of cooling water, which verifies the model can be applied in engineering practice.

关键词： cooling water generalized curvilinear coordinate non-staggered grids numerical simulation SIMPLE algorithm

Optimal Portfolio and Consumption Rule with a CIR Model Under HARA Utility

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Journal of the Operations Research Society of China 2018年第1期6卷 107-137页

作者： Chun-Feng Wang Hao Chang Zhen-ming fang College of Management and Economics Tianjin UniversityTianjin 300072China School of Science Tianjin Polytechnic UniversityTianjin 300387China

In the real-world environments,different individuals have different risk *** paper investigates the optimal portfolio and consumption rule with a Cox–Ingersoll–Ross(CIR)model in a more general utility *** consumption,an individual invests his wealth into the financial market with one risk-free asset and multiple risky assets,where the short-term rate is driven by the CIR model and stock price dynamics are simultaneously influenced by random sources from both stochastic interest rate and stock market *** individual hopes to optimize their portfolios and consumption rules to maximize expected utility of terminal wealth and intermediate *** preference of individual is assumed to satisfy hyperbolic absolute risk aversion(HARA)utility,which contains power utility,logarithm utility,and exponential utility as special *** using the principle of stochastic optimality and Legendre transform-dual theory,the explicit expressions of the optimal portfolio and consumption rule are *** sensitivity of the optimal strategies to main parameters is analysed by a numerical *** addition,economic implications are also *** research results show that Legendre transform-dual theory is an effective methodology in dealing with the portfolio selection problems with HARA utility and interest rate risk can be completely hedged by constructing specific portfolios.

关键词： CIR model Optimal portfolios and consumption rules HARA utility Legendre transform-dual theory Stochastic optimal control Economic implicati

Flow Characteristics of Double-Cruciform Parachute at Inflating and Inflated Conditions

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第6期35卷 992-999页

作者： fang ming Sun Jianhong Zhang Tong Hou Bin Zhang Yantai Key Laboratory of Aircraft Environment Control and Life Support of MIIT College of Aerospace EngineeringNanjing University of Aeronautics and Astronautics

The fluid-structure interaction (FSI) between the canopy and flow field on the inflating and inflated conditions is investigated based on the arbitrary Lagrange-Euler (ALE) method,in both a single-and double-cruciform parachute *** projection area of canopy is calculated in the inflation *** flow field characteristics and the interaction between canopies are *** showed that,with free stream velocity of 50m/s,overinflation phenomenon would not occur during the inflation process of the double-cruciform-parachute system,because the collision and extrusion of the two canopies during inflation obstructed the oscillation of the inner ***,compared with the single-cruciform parachute,the vortex motion in the wake of double-cruciform-parachute is more *** the double-cruciform parachute system oscillated at a velocity of 50 m/s with an angle of less than 6.8°.By comparison,the oscillation angle of the single-cruciform parachute was within 3.5° at the velocity of 50m/*** results are consistent with those of the wind tunnel test.

关键词： process of inflation arbitrary Lagrange-Euler(ALE) Lamb vector divergence cruciform parachute

Alterations of Alternative Splicing Patterns of Ser/Arg-Rich (SR) Genes in Response to Hormones and Stresses Treatments in Different Ecotypes of Rice (Oryza sativa)

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Journal of Integrative Agriculture 2013年第5期12卷 737-748页

作者： ZHANG Peng DENG Heng XIAO fang-ming LIU Yong-sheng Key Laboratory for Bio-Resource and Eco-Environment Ministry of Education/State Key Laboratory of Hydraulics and Mountain River Engineering/College of Life Science Sichuan University Neijiang Hybrid Rice Research and Development Center Department of Plant Soil and Entomological Sciences University of Idaho School of Biotechnology and Food Engineering Hefei University of Technology

Ser/Arg-rich （SR） genes encode proteins that play pivotal roles in both constitutive and alternative splicing of pre-mRNA. However, not much effort has been made to investigate the alternative splicing of their own pre-mRNA. In this study, we conducted comprehensive analyses of pre-mRNA splicing for 22 SR genes in three rice （Oryza sativa L.） ecotypes indica, japonica andjavanica. Using different ecotypes we characterized the variations in expression and splicing patterns of rice SR genes in different tissues and at different developmental stages. In addition, we compared the divergence in expression and splicing patterns of SR genes from seedlings of different rice ecotypes in response to hormones application and environmental stresses. Our results revealed the complexity of alternative splicing of SR genes in rice. The splicing varies in different tissues, in different ecotypes, in response to stresses and hormones. Thus, our study suggested that SR genes were subjected to sophisticated alternative splicing although their encoding proteins were involved in the splicing process.

关键词： SR protein alternative splicing stress rice

先天性左心耳发育不良或是左心耳未发育—探寻其影像学诊断及其临床意义

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中国CT和MRI杂志 2024年第7期22卷 74-76页

作者：李炜庞茂华周华王伟袁明远方明上海浦东新区周浦医院放射科上海200000 上海中医药大学附属龙华医院心病科上海200000

目的探寻左心耳发育不良和左心耳未发育的影像学表现,并了解此类先天性畸形的临床意义。方法收集我院2018年10月至2021年12月期间影像学诊断左心耳缺如患者5例,均有心脏CT血管造影(CT angiography,CTA)、经食道超声心动图(transesophage... 详细信息

目的探寻左心耳发育不良和左心耳未发育的影像学表现,并了解此类先天性畸形的临床意义。方法收集我院2018年10月至2021年12月期间影像学诊断左心耳缺如患者5例,均有心脏CT血管造影(CT angiography,CTA)、经食道超声心动图(transesophageal echocardiography,TEE)及肺部CT平扫检查,对他们的影像和临床资料进行回顾性分析。结果5例食管超声检查中,3例报告左心耳未见显示,2例报告左心耳极细小且自发显影;5例肺静脉CTA中,1例肺静脉期及延迟期均未见左心耳显影;2例肺静脉期未见左心耳显影,延迟期极少量对比剂充盈左心耳;2例肺静脉期左心耳线状对比剂充盈,延迟期左心耳显影范围略扩大。5例肺部CT平扫均可以在正常位置显示极小的左心耳解剖形态。所有患者冠状静脉窦结构正常,管径不同程度扩张。5例房颤患者CHA2DS2-VASc卒中评分为7分,7分,6分,7分,6分,均为高危卒中患者,4例患者有反复腔隙性脑梗塞,1例患者曾发生有大面积脑梗塞。结论本组影像学初步诊断左心耳缺如的5例患者,结合其胸部CT平扫,发现左侧房肺沟均存在类似极小指状结构且其内部梳状肌发达、残余管腔极为细小,因此,类似病例是否左心耳真正解剖意义上的缺如值得商榷,归结为左心耳发育不良似乎更为妥当。左心耳发育不良的房颤患者,临床血栓事件并未减少,其临床卒中风险可能仅与CHA2DS2-VASc评分相关。

关键词：左心耳发育不良左心耳缺如血栓栓塞多模态影像学

Synthesis of γ-Al2O3 with High Surface Area and Large Pore Volume by Reverse Precipitation- azeotropic Distillation Method

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Chemical Research in Chinese Universities 2013年第2期29卷 206-209页

作者： WU Yu-sheng MA Jiao LI ming-chun HU fang School of Materials Science and Engineering Shenyang University of Technology Shenyang 110870 P. R. China

γ-Al2O3 with high surface area and large pore volume combined with high thermal stability was synthe- sized by a reverse precipitation-azeotropic distillation method. The effects of azeotropic distillation on the characte- ristics of γ-Al2O3 were studied by means of X-ray diffraction（XRD）, Fourier transform infrared（FTIR） spectroscopy, transmission electron microscopy（TEM） and N2 adsorption-desorption. The results show that γ-Al2O3 dried by azeo- tropic distillation has excellent structure characteristics with a high surface area of 426 m2/g and a large pore volume of 2.56 cm3/g. After calcination at 1100 ℃, the surface area of γ-Al2O3 was still 92 mE/g with a large pore volume of 1.00 cma/g, indicating the potential application in catalyst and petroleum industry.

关键词： Reverse precipitation Azeotropic distillation y-Alumina n-Butyl alcohol Thermal stability