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Synthesis and morphology of triangular pyramid-shaped puerarin microparticle with nanostructure

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Chinese Chemical Letters 2010年第4期21卷 484-487页

作者： lu, Chuan Hua Zhang, qun wei Anhui Coll Tradit Chinese Med Sch Pharm Hefei 230038 Peoples R China

A type of triangular pyramid-shaped microparticles of puerarin was synthesized by using oil-in-oil microemulsion approach which is simple and economical under the action of copper *** pyramid-shaped microparticles would be made up of deposit of nanospheres or nanorods and have two significant *** is its complex surface morphology like coral *** other is a lot of nanopores in existence in the microparticle *** possible formation routes were speculated.

关键词： Triangular pyramid-shaped puerarin microparticles Synthesis Nanosphere Nanorod

The effect of Compton scattering on gamma-ray spectra of the 2005 January 20 flare

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Research in Astronomy and Astrophysics 2012年第10期12卷 1439-1450页

作者： wei Chen wei-qun Gan Key Laboratory of Dark Matter and Space Astronomy Purple Mountain Observatory ChineseAcademy of Sciences Nanjing 210008 China

Gamma-ray spectroscopy provides a wealth of information about acceler- ated particles in solar flares, as well as the ambient medium with which these energetic particles interact. The neutron capture line （2.223 MeV）, the strongest in the solar gamma-ray spectrum, forms in the deep atmosphere. The energy of these photons can be reduced via Compton scattering. With the fully relativistic GEANT4 toolkit, we have carried out Monte Carlo simulations of the transport of a neutron capture line in solar flares, and applied them to the flare that occurred on 2005 January 20 （X7.1/2B）, one of the most powerful gamma-ray flares observed by RHESSI during the 23rd solar cycle. By comparing the fitting results of different models with and without Compton scattering of the neutron capture line, we find that when including the Compton scat- tering for the neutron capture line, the observed gamma-ray spectrum can be repro- duced by a population of accelerated particles with a very hard spectrum （s ≤ 2.3）. The Compton effect of a 2.223 MeV line on the spectra is therefore proven to be sig- nificant, which influences the time evolution of the neutron capture line flux as well. The study also suggests that the mean vertical depth for neutron capture in hydrogen for this event is about 8 g cm-2.

关键词： Sun: flares -- Sun: gamma-rays -- scattering: Compton scattering

A subband excitation substitute based scheme for narrowband speech watermarking

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Frontiers of Information Technology & Electronic Engineering 2017年第5期18卷 627-643页

作者： wei LIU Ai-qun HU School of lnformation Science and Engineering Southeast UniversityNanjing 210096China

We propose a new narrowband speech watermarking scheme by replacing part of the speech with a scaled and spectrally shaped hidden signal. Theoretically, it is proved that if a small amount of host speech is modified, then not only an ideal channel model for hidden communication can be established, but also high imperceptibility and good intelligibility can be achieved. Furthermore, a practical system implementation is proposed. At the embedder, the power normalization criterion is first imposed on a passband watermark signal by forcing its power level to be the same as the original passband excitation of the cover speech, and a synthesis filter is then used to spectrally shape the scaled watermark signal. At the extractor, a bandpass filter is first used to get rid of the out-of-band signal, and an analysis filter is then employed to compensate for the distortion introduced by the synthesis filter. Experimental results show that the data rate is as high as 400 bits/s with better bandwidth efficiency, and good imperceptibility is achieved. Moreover, this method is robust against various attacks existing in real applications.

关键词： Analysis filter Linear prediction Narrowband speech watermarking Passband excitation replacement Power normalization Spectral envelope shaping Synthesis filter

湿、热、静力荷载对速生杉木顺纹抗压强度的影响

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林业机械与木工设备 2016年第11期44卷 34-37,42页

作者：王志强王转转唐岳磊董惟群魏鹏卢晓宁南京林业大学材料科学与工程学院江苏南京210037 徐州盛和木业有限公司江苏徐州221321

研究不同湿热环境中,在湿、热荷载、静力荷载作用下速生杉木的顺纹抗压强度,并分析了温度、相对湿度、静力荷载和保载时间4个因素对速生杉木顺纹抗压强度的影响。试验结果表明,速生杉木顺纹抗压强度随环境温、湿度增高而降低,环境温度... 详细信息

研究不同湿热环境中,在湿、热荷载、静力荷载作用下速生杉木的顺纹抗压强度,并分析了温度、相对湿度、静力荷载和保载时间4个因素对速生杉木顺纹抗压强度的影响。试验结果表明,速生杉木顺纹抗压强度随环境温、湿度增高而降低,环境温度对速生杉木顺纹抗压强度影响非常显著;在相同的静力荷载条件下,有湿、热荷载同时作用的速生杉木顺纹抗压强度降低,平均降低幅度为20.10%;湿、热、静力荷载共同作用对速生杉木顺纹抗压强度存在耦合影响。

关键词：湿、热、静力荷载耦合作用顺纹抗压强度速生杉木

Nonsolvable D_2-groups

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Acta Mathematica Sinica,English Series 2015年第11期31卷 1683-1702页

作者： Yang LIU Zi qun lu Beijing International Center for Mathematical Research Peking University Department of Mathematics Tsinghua University

Let G be a finite group. Let Irrl（G） be the set of nonlinear irreducible characters of G and cdl（G） the set of degrees of the characters in Irr1（G）. A group G is said to be a D2-group if led1 （G）[ = ]Irr1 （G）I - 2. The main purpose of this paper is to classify nonsolvable D2-groups. Keywords Character degree, degree multiplicity, nonsolvable group

关键词： Character degree degree multiplicity nonsolvable group

Active gastrointestinal diverticulum bleeding diagnosed by computed tomography angiography

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World Journal of Gastroenterology 2014年第37期20卷 13620-13624页

作者： Xie-qun Xu Tao Hong Bing-lu Li wei Liu Department of General Surgery Peking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical College

A diverticulum is a bulging sack in any portion of the gastrointestinal tract. Small intestine diverticular disease is much less common than colonic diverticular disease. The most common symptoms include non-specific epigastric pain and a bloating sensation. Major complications include diverticulitis, gastrointestinal bleeding, acute perforation, intestinal obstruction, intestinal perforation, localized abscess, malabsorption, anemia,volvulus and bacterial overgrowth. We report one case of massive jejunal diverticula bleeding and one case of massive colonic diverticula bleeding, both diagnosed by acute abdominal computed tomography angiography and treated successfully by surgery.

关键词： Diverticulum Gastrointestinal diverticular bleeding Angiography Computed tomography angiography Endoscopy

Ileo-ileal intussusception caused by diffuse large B-cell lymphoma of the ileum

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World Journal of Gastroenterology 2013年第45期19卷 8449-8452页

作者： Xie-qun Xu Tao Hong Bing-lu Li wei Liu Department of General Surgery Peking Union Medical College Hospital Chinese Academy of Medical Sciences and Peking Union Medical College

The occurrence of adult intussusception from small intestinal lymphoma is quite *** present an82-year-old man with a two-month history of intermittent abdominal pain,nausea and *** symptoms included moderate abdominal tenderness in the right lower *** tomography scan of the abdomen revealed a mass in the terminal ileum with the sign of"bowel within bowel"which was suspicious of ileo-ileum *** patient underwent laparoscopic segmental ileal *** evaluation revealed a diffuse large B cell non-Hodgkin’s lymphoma of the *** postoperative course was uneventful.

关键词： Adult intussusception Lymphoma Small intestine Ileum

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Solvable D_2-Groups

Acta Mathematica Sinica,English Series 2017年第1期33卷 77-95页

作者： Yang LIU Zi qun lu School of Mathematical Science Tianjin Normal University Department of Mathematics Tsinghua University

Let G be a finite group, Irra（G） be the set of nonlinear irreducible characters of G and cdl （G） the set of degrees of the characters in Irrl （G）. A group G is said to be a D2-group if │cdl （G）│ = │Irrl（G... 详细信息

关键词： Character degree degree multiplicity solvable group

Stochastic response analysis of noisy system with non-negative real-power restoring force by generalized cell mapping method

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Applied Mathematics and Mechanics(English Edition) 2015年第3期36卷 329-336页

作者： qun HAN wei XU Xiaole YUE Department of Applied Mathematics Northwestern Polytechnical University

The stochastic response of a noisy system with non-negative restoring force is investigated. The generalized cell mapping （GCM） method compute the transient and stationary probability density functions （PDFs） real-power is used to Combined with the global properties of the noise-free system, the evolutionary process of the tran- sient PDFs is revealed. The results show that stochastic P-bifurcation occurs when the system parameter varies in the response analysis and the stationary PDF evolves from bimodal to unimodal along the unstable manifold during the bifurcation.

关键词： stochastic response probability density function (PDF) generalized cell mapping (GCM) method real-power restoring force bifurcation