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Several Expressions of Dirichlet L-function at Positive Integers

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Acta Mathematica Sinica,English Series 2019年第9期35卷 1549-1562页

作者： yuan he School of Mathematics and Information Science Neijiang Normal University

In this paper, by making use of Abel’s theorem on power series, the reflection formula and the function equation for Hurwitz zeta function, we establish several expressions of Dirichlet Lfunction at positive integers by means of some finite sums of different types. Some special cases as well as immediate consequences of the results presented here are also considered.

关键词： Dirichlet L-function trigonometric sums gauss sums bernoulli polynomials combinatorial identities

Preparation of a cationic azobenzene dye-montmorillonite intercalation compound and its photochemical behavior

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Journal of University of Science and Technology Beijing 2006年第3期13卷 281-286页

作者： Tao Wan Yi yuan Wenqiong he College of Materials and Chemistry ＆ Chemical Engineering Chengdu University of Technology Chengdu 610059 China

Montmorillonite/cationic azobenzene dye （GTL） intercalation compounds were prepared by the conventional ion exchange method. As compared with that of pure GTL, the thermal stability of the intercalated GTL was greatly enhanced, and the absorption band corresponding to azobenzene group in intercalated GTL shifted towards a longer wavelength by 55 nm, which could be ascribed to the strong conjugation of GTL supramolecular order structure （J cluster） confined in a nanoscale space of montmorillonite interlayer gallery. The microstructures of the resulting intercalation compounds could be successfully controlled by varying the amount of dye loaded as evidenced by the basal spacing of the intercalation compounds. The intercalated azo dye in the montmorillonite interlayer space exhibited reversible trans-to-cis photoisomerization and thermal cis-to-trans reaction. FTIR proved the successful intercalation of GTL into the silicate layer.

关键词： Na-montmorillonite azobenzene intercalation photoisomerization

Multi-level spherical moments based 3D model retrieval

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2006年第9期7卷 1500-1507页

作者： LIU Wei he yuan-jun Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China

In this paper a novel 3D model retrieval method that employs multi-level spherical moment analysis and relies on voxelization and spherical mapping of the 3D models is proposed. For a given polygon-soup 3D model, first a pose normalization step is done to align the model into a canonical coordinate frame so as to define the shape representation with respect to this orientation. Afterward we rasterize its exterior surface into cubical voxel grids, then a series of homocentric spheres with their center superposing the center of the voxel grids cut the voxel grids into several spherical images. Finally moments belonging to each sphere are computed and the moments of all spheres constitute the descriptor of the model. Experiments showed that Euclidean distance based on this kind of feature vector can distinguish different 3D models well and that the 3D model retrieval system based on this arithmetic yields satisfactory performance.

关键词： 3D model retrieval Spherical moments Feature extraction Pose normalization

Effect of ramipril on progression of nonculprit lesions in patients with ST-elevation myocardial infarction after primary percutaneous coronary intervention

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Journal of Geriatric Cardiology 2019年第9期16卷 695-700页

作者： Jian WANG Song-yuan he Department of Cardiology Aerospace Central Hospital Aerospace Clinical Medical College of Peking University

Objective To investigate the effect of ramipril on progression of nonculprit lesions in patients with ST-elevation myocardial infarction(STEMI) after primary percutaneous coronary intervention(PPCI). Methods A total of 200 patients(60.1 ± 11.3 years) with STEMI who underwent successful PPCI from January 2010 to December 2013 were enrolled in this study. All patients underwent PPCI as treatment for culprit lesions. Patients were divided into two groups according to the dosage of ramipril used at hospital discharge as follows: high dosage group(2.5–10 mg, q.d.) and low dosage group(1.25–2.5 mg, q.d.). Clinical and angiographic follow-up was performed for 12 months. The primary endpoint was clinically-driven percutaneous coronary intervention(PCI) for nonculprit lesions. The clinical and angiographic features were analyzed. Results Clinical and angiographic follow-up was performed with 87 patients in the high dosage group and 113 patients in the low dosage group. The numbers of patients who underwent additional PCI were six and 20 in the high and low dosage groups, respectively. The rate of having additional PCI performed was lower in the high dosage group than in the low dosage group(6.90% vs. 17.70%, P = 0.03). Conclusions A high dosage of ramipril may prevent progression of nonculprit lesions, which could be the major cause of recurrent PCI in patients with STEMI after PPCI.

关键词： Nonculprit lesion Primary percutaneous coronary intervention Ramipril ST-elevation myocardial infarction

Comprehensive drought monitoring in Yunnan Province, China using multisource remote sensing data

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Journal of Mountain Science 2021年第6期18卷 1537-1549页

作者： WANG Jin-liang YU yuan-he Faculty of Geography Yunnan Normal UniversityKunming 650500China Key Laboratory of Resources and Environmental Remote Sensing for Universities in Yunnan Kunming 650500China Center for Geospatial Information Engineering and Technology of Yunnan Province Kunming 650500China

Development of drought monitoring techniques is important for understanding and mitigating droughts and for rational agricultural management. This study used data from multiple sources, including MOD13 A3, TRMM 3 B43, and SRTMDEM, for Yunnan Province, China from 2009 to 2018 to calculate the tropical rainfall condition index(TRCI), vegetation condition index(VCI), temperature condition index(TCI), and elevation factors. Principal component analysis(PCA) and analytic hierarchy process(AHP) were used to construct comprehensive drought monitoring models for Yunnan Province. The reliability of the models was verified, following which the drought situation in Yunnan Province for the past ten years was analysed. The results showed that:(1) The comprehensive drought index(CDI) had a high correlation with the standardized precipitation index, standardized precipitation evapotranspiration index, temperature vegetation dryness index, and CLDAS(China Meteorological Administration land data assimilation system), indicating that the CDI was a strong indicator of drought through meteorological, remote sensing and soil moisture monitoring.(2) The droughts from 2009 to 2018 showed generally consistent spatiotemporal changes. Droughts occurred in most parts of the province, with an average drought frequency of 29% and four droughtprone centres.(3) Monthly drought coverage during 2009 to 2014 exceeded that over 2015 to 2018. January had the largest average drought coverage over the study period(61.92%). Droughts at most stations during the remaining months except for October exhibited a weakening trend(slope > 0). The CDI provides a novel approach for drought monitoring in areas with complex terrain such as Yunnan Province.

关键词： Multisource data Comprehensive drought index(CDI) Standardized precipitation index(SPI) Standardized precipitation evapotranspiration index(SPEI) Temperature vegetation dryness index(TVDI) Yunnan Province China

Effects of light and salinity on carotenoid biosynthesis in Ulva prolifera

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Acta Oceanologica Sinica 2020年第10期39卷 50-57页

作者： yuan he yuantu Ye Songdong Shen College of Biology and Basic Medical Sciences Soochow UniversitySuzhou 215123China

Ulva prolifera is a green alga that plays an important role in green *** biosynthesis is a basic terpenoid metabolism that is very important for maintaining normal life activities in *** this study,we first reported the complete sequences of all genes in the 2-C-methyl-D-erythritol 4-phosphate(MEP)pathway,which is the only carotenoid synthesis pathway in ***,we compared these genes with those of other ***,by detecting the carotenoid contents and expression levels of key genes participating in carotenoid biosynthesis in *** under three different light(1000 lx,5000 lx and 12000 lx)and salinity(12,24 and 40)regimes,we found that carotenoid synthesis could be influenced by light and salinity,such that low light and high salinity could promote the synthesis of *** results showed that the expression levels of genes involved in the MEP and the downstream pathway could affect the biosynthesis of carotenoids at the molecular *** study contributes to a better understanding of the roles of genes participating in carotenoid biosynthesis in *** and the environmental regulation of these genes.

关键词： U.prolifera carotenoid MEP pathway light salinity

Effect of geometry simplification and boundary condition specification on flow field and aerodynamic noise in the train head and bogie region of high-speed trains

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第9期25卷 716-731页

作者： Jiawei SHI yuan he Jiye ZHANG Tian LI State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu 610031China Institute of Sound and Vibration Research Faculty of Engineering and Physical SciencesUniversity of SouthamptonSouthampton SO171BJUK

The purpose of this study is to determine a suitable modeling method to make computational fluid dynamics(CFD)simulation more efficient for aeroacoustics optimization of the bogie region of high-speed *** this end,four modeling methods are considered,which involve different geometry simplifications and boundary condition *** corresponding models are named the three-car marshalling model,computational domain shortening model,carbody shortening model,and sub-domain *** the detached eddy simulation(DES)model and Ffowcs Williams-Hawkings(FW-H)equation,the unsteady flow field and far-field noise of the four models are *** evaluate the effect of the different modeling methods,the time-averaged flow field,fluctuating flow field,and far-field noise results of the four models are compared and analyzed in detail with the results of the three-car marshalling model used as basis for *** results show that the flow field results of the bogie region predicted by the four models have relatively high ***,the usage of the non-time varying outlet boundary conditions in the computational domain shortening model and sub-domain model could affect the pressure fluctuation on the upstream carbody *** only the bogie region is used as the source surface,the differences between the far-field noise results of the three simplified models and the three-car marshalling model are all within 1 dB;when the train head is used as the source surface,the results of the carbody shortening model and the three-car marshalling model are more consistent.

关键词： Bogie region Train head Flow field Aerodynamic noise Geometry simplification Boundary conditions

Investigation of the shock compression behaviors of Al/PTFE composites with experimental and a 3D mesoscale-model

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Defence Technology（防务技术） 2022年第1期18卷 62-71页

作者： Xiang-li Yang Yong he yuan he Chuan-ting Wang Jie Zhou Departnentsof Mecharical Engneering Nanjing Uriversity of Science&Technology NanjingJiangsu210094PR China Hubei Aeros pace Flight Vehide Institute Wuhan 430040PR China

The responses of Al/PTIFE reactive materials(RMs)under shock compression were investigated by a single-stage gas gun.A 3D mesoscale-model was established based on micro-computed tomography(micro-CT)slice images and confirmed with experimental *** the high-pressure stage,the com-posites reacted partially,whereas there were no deviations between the partially reacted Hugoniot and the inert simulation *** simulation reveals that the Teflon matrix melting on the high shock *** and decomposition of the PTFE accelerated the diffusion of the ***,the reactions of the Al/PTFE composites are more like a combustion rather than a detonation.

关键词： AI/PTFE reactive materials 3D mesoscale-model Shock-assisted reaction Shock Hugoniot

The recombinant expression systems for structure determination of eukaryotic membrane proteins

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Protein & Cell 2014年第9期5卷 658-672页

作者： yuan he Kan Wang Nieng Yan State Key Laboratory of Bio-membrane and Membrane Biotechnology Tsinghua university Beijing 100084 China Center for Structural Biology School of Medicine Tsinghua university Beijing 100084 China China-Japan Friendship Hospital Beijing 100029 China

Eukaryotic membrane proteins, many of which are key players in various biological processes, constitute more than half of the drug targets and represent important candidates for structural studies. In contrast to their physiological significance, only very limited number of eukaryoUc membrane protein structures have been obtained due to the technical challenges in the genera- tion of recombinant proteins. In this review, we examine the major recombinant expression systems for eukaryotic membrane proteins and compare their relative advantages and disadvantages. We also attempted to summarize the recent technical strategies in the advancement of eukaryotic membrane protein purification and crystallization.

关键词： eukaryotic membrane proteins,recombinant expression structural biology integralmembrane proteins (IMPs) fluorescence detected sizeexclusion chromatography (FSEC) protein purification and crystallization