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Absolute parameters and physical nature of two W-UMa type binaries:V1123 Tau and V1128 Tau

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Research in Astronomy and Astrophysics 2011年第5期11卷 583-593页

作者： xiao-binzhang An-BinReni Chang-QingLuc Yang-PingLuo NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012China InstituteofTheoreticalPhysics ChinaWestNormalUniversityNanchong637002China NationalAstronomicalObservatories／YunnanObservatory ChineseAcademyofSciencesKunming650011China

We present high-precision, multi-band CCD photometry of two less-studied close binaries V1123 Tau and V1128 Tau. Complete covered light curves and a number of new times of light minima of the two eclipsing systems were obtained, based on which, revised orbital elements and new ephemerides were given. By adopting the Wilson-Devinney method, the light curves were analyzed. The photometric solutions confirm the W UMa-type nature of the binary systems. With the less-massive secondary slightly cooler than the primary, V1123 Tau could be classified as an A- type contact system. While V1128 Tau is typically considered a W-type W UMa star, the surface temperature of its secondary component is determined to be absolutely higher than the primary by about 270 K. Combining with the results of radial-velocity solutions, we determined absolute parameters of the two systems. The mass, radius and luminosity for each component of V1123 Tau were derived as： 1.36 ±0.05M⊙, 1.37 ± 0.02R⊙, and 2.01± O.07L⊙ and 0.40±0.02M⊙, 0.80±0.01R⊙, and 0.67±0.04L⊙, respectively. For V1128 Tau, the absolute parameters were computed to be 1.09±0.03M⊙, 1.01±0.01R⊙, and 1.34±0.06Le and 0.58 ± 0.01M⊙, 0.76±0.01R⊙, and 0.91±0.05L⊙, respectively. Based on these results, the evolutionary status and the physical nature of the two binary systems are discussed, while also connecting with the theoretical models.

关键词： binaries: eclipsing-stars: late-type-stars: activity -stars: individ-ual (V1123 Tau Vl128 Tau)

Discovery of Three Variable Stars in Direction toward NGC 4565

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Chinese Journal of Astronomy and Astrophysics 2004年第5期4卷 411-414页

作者： LeiLi HongWu xiao-binzhang Ya-BoWu XuZhou Zhao-JiJiang JunMa NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012 DepartmentofPhysics LiaoningNormalUniversityDalian116029

We present the results of a variable star search in a field next to the edge-on galaxies NGC 4565 from the archive data of Beijing-Arizona-Taibei-Connecticut Multicolor Sky Survey. Three new variable stars were discovered. Based on spectra obtained from the 2.16m NAOC telescope, we identify two of these as RR Lyr stars and one as a special T Tauri star.

关键词： stars: variables: RR Lyr stars: variables: T Tauris

Clinical value of Helicobacter pylori stool antigen test,Immuno Card STAT HpSA,for detecting Hpylori infection

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World Journal of Gastroenterology 2004年第6期10卷 913-914页

作者： Yi-HuiLi HongGuo Peng-binzhang xiao-YanZhao Si-PingDa DepartmentofGastroenterology XinqiaoHospitalThirdMilitaryMedicalUniversityChongqing400037China

AIM:To evaluate the reliability of the Helicobacter pylori stool antigen test, ImmunoCard STAT HpSA, for detecting Hpylori ***:Stool specimens were collected from 53 patients who received upper endoscopy examination due to gastrointestinal *** STAT HpSA was used to detect Hpylori stool antigens. Hpylori infection was detected based on three different tests:the urease test,Warthin-Starry staining and culture. Hpylori status was defined as positive when both the urease test and histology or culture alone was ***:Sensitivity,specificity,positive predictive and negative predictive values and the total accuracy of ImmunoCard STAT HpSA for the diagnosis of Hpyloriinfection were 92.6% (25/27), 88.5% (23126), 89.3% (25/28), 92%(23/25) and 90.6% (48/53), ***:The stool antigen test, ImmunoCard STAT HpSA,is a simple noninvasive and accurate test for the diagnosis of Hpylori infection.

关键词：幽门螺杆菌粪便抗原检测诊断消化道溃疡 ImmunoCard STAT HpSA

Image Authentication Based on Digital Signatureand Semi-Fragile Watermarking

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Journal of Computer Science & Technology 2004年第6期19卷 752-759页

作者： Hong-binzhang ChengYang xiao-MeiQuan CollegeofComputerScience BeijingUniversityofTechnologyBeijing100022P.R.China

This paper proposes an authentication scheme for JPEG images based on digital signature and semi-fragile watermarking. It can detect and locate malicious manipulations made to the image, and verify the ownership of the image at the same time. The algorithm uses the invariance of the order relationship between two DCT coefficients before and after JPEG compression to embed image content dependent watermark, therefore the watermark can survive the JPEG lossy compression. Since the scheme is based on the security of the cryptographic hash function and public key algorithm, it is believed to be secure to the extent that cryptography is believed to be. Theoretical analysis and experimental results show that the proposed scheme has the desired property and good performance for image authentication.

关键词： image authentication semi-fragile watermarking JPEG digital signature

Chemical Constituents of Schisandra rubriflora Rehd. et Wils.

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Journal of Integrative Plant Biology 2005年第3期47卷 362-367页

作者： Gan-PengLI Jing-FengZHAO Yong-QiangTU xiao-DongYANG Hong-binzhang LiangLI SchoolofPharmacy YunnanUniversityKunming650091China／／SchoolofChemistryandBiotechnologyYunnanNationalitiesUniversityKunming650031China SchoolofPharmacy YunnanUniversityKunming650091China DepartmentofChemistry NationalLaboratoryofAppliedOrganicChemistryLanzhouUniversityLanzhou730000China

Abstract: Schisandra rubriflora Rehd. et Wils. is a traditional Chinese medicine. To search for new and bioactive components from traditional Chinese medicines and provide scientific evidence for taxonomy, the chemical constituents of the plant were investigated by various column chromatography methods (silica gel, Sephadex LH-20, and RP-18). From the aerial parts of S. rubriflora, three new megastigmane glycosides, namely (3S, 5R, 6S, 9R)-megastigmane-3, 9-diol 3-O-[α-L-arabionfuranosyl-(1→6)-β-D-glucopyranoside] (1), 7-megastigmene-3-ol-9-one 3-O-[α-L-arabionfuranosyl-(1→6)-β-D-glucopyranoside] (2), and megastigmane-3α, 4β, 9σ-triol 3-O-β-D-glucopyranoside (3), along with 14 known compounds, were isolated. The structures of the new compounds were elucidated by a combination of spectroscopic and chemical methods.

关键词： alangionoside megastigmane glycosides Schisandra rubriflora Rehd. et Wils Schisandraceae

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太阳水泵设计计算及性能分析

太阳能学报 1991年第1期12卷 11-18页

作者：许新中霍志臣阎晓彬张家斌朱正阳北京市太阳能研究所

本文对汽压式双隔膜太阳水泵的设计计算进行了讨论,并对主要部件作了性能分析。试验装置在西藏现场运行结果表明,太阳水泵的实用效果与设计指标、理论分析相吻合。

关键词：水泵太阳能设计计算性能

Serum hepatic enzyme manifestations in patients with severe acute respiratory syndrome:Retrospective analysis

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World Journal of Gastroenterology 2004年第11期10卷 1652-1655页

作者： Hui-JuanCui xiao-LinTong PingLi Ying-XuHao xiao-GuangChen Ai-GuoLi Zhi-YuanZhang JunDuan MinZhen binzhang Chuan-JinHua Yue-WenGong Chinese-JapaneseFriendshipHospital Beijing100029China FacultyofPharmacy UniversityofManitobaCanada

AIM: To evaluate the hepatic function in patients with severe acute respiratory syndrome (SARS) and possible causes of hepatic disorder in these patients. METHODS: One hundred and eighty-two patients with SARS were employed in a retrospective study that investigated hepatic dysfunction. Liver alanine aminotransferase (ALT), aspartate aminotransferase (AST) and lactic dehydrogenase (LDH) were analyzed in these patients. Patients with different hospital treatments were further investigated. RESULTS: Of the 182 patients, 128(70.3%) had abnormal ALT activity, 57(31.3%) had abnormal AST activity and 87(47.8%) had abnormal LDH activity. The peak of elevated hepatic enzyme activities occurred between the sixth day and the tenth day after the first day of reported fever. Of the 182 patients, 160(87.9%) had been treated with antibiotics, 137(75.2%) with Ribavirin, and 115(63.2%) with methylpredisolone. There was no statistically significant correlation between the duration of Ribavirin treatement and hepatic dysfunction. CONCLUSION: Abnormal liver functions were common in patients with SARS and could be associated with virus replication in the liver.

关键词：免疫血清肝脏酶表达急性呼吸窘迫综合征 SARS 非典型肺炎 AST ALT

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基于数字签名和半脆弱水印的图像认证

Journal of Computer Science & Technology 2004年第C期19卷 67-67页

作者： Hong-binzhang ChengYang xiao-MeiQuan CollegeofComputerScience BeijingUniversityofTechnologyBeijng100022P.R.China

目前，虽然有不少图像内容认证的算法发表，但在性能和安全性上仍有许多问题需要进一步的研究。作者认为，一个安全性高的压缩域认证算法应该具有如下性质：

关键词：脆弱水印图像认证数字签名图像内容算法压缩域安全性性能