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Stable Propagating Waves and Wake Fields in Relativistic Electromagnetic Plasma

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Communications in Theoretical Physics 2008年第3期49卷 753-758页

作者： XIE bai-Song yin Xin-Tao The Key Laboratory of Beam Technology and Materials Modification of Ministry of Education Beijing Normal University Beijing 100875 China

Stable propagating waves and wake fields in relativistic electromagnetic plasma are investigated. The incident electromagnetic field has a finite initial constant amplitude meanwhile the longitudinal momentum of electrons is taken into account in the problem. It is found that in the moving frame with transverse wave group velocity the stable propagating transverse electromagnetic waves and longitudinal plasma wake fields can exist in the appropriate regime of plasma.

关键词： nonlinear wave propagation laser-plasma interactions

Theoretical analysis and numerical simulation on behaviour properties of large span cable-supported structures under fire conditions

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Science China(Technological Sciences) 2009年第8期52卷 2340-2349页

作者： bai yin SHI YongJiu WANG YuanQing Department of Civil Engineering Key Laboratory of Structural Engineering and Vibration of China Education MinistryTsinghua UniversityBeijing 100084China

Large span cable-supported structures have been developed rapidly in China, and they always adopt high-strength steel cables as structural members. However, the modulus of elasticity and yield strength of steel material will decrease seriously under fire conditions while fire protection is unlikely to be provided for steel cable. Several typical large span cable-supported structures such as cable truss, beam string structure and prestressed cable net are studied on their structural behaviour in this paper. Theoretical formulae are derived in terms of geometrical and material nonlinearity with high temperature effect. Finite element models are also established to simulate the structural performance under fire conditions. The calculation formulae for fire-resisting design are suggested for these three types of structures, while displacement and prestressed force variation rules are also given.

关键词： cable-supported structure fire resisting design theoretical deriviation prestensioning force variation FEA model

Effect of Triisopropanolamine on the Compressive Strength and Early Hydration of Cement at Low Temperature

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Journal of Wuhan University of Technology(Materials Science) 2020年第3期35卷 611-619页

作者： ZHANG Feng bai yin CAI Yuebo CHEN Bo NING Fengwei State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Nanjing Hydraulic Research InstituteNanjing 210029China

Triisopropanolamine (TIPA) was used as an early strength component to study its effects on mortar strength, cement paste setting time and early hydration characteristic of cement. And the early strength mechanism of TIPA at low temperature of 5 ℃ was also discussed. The results showed that, at 5 ℃, the incorporation of TIPA promoted the condensation of cement paste, shortened the initial and final setting time, and accelerated the strength development of specimens at all ages, among which the strength after 3 d increased significantly. The 1, 3, 7, and 28 d compressive strength ratios of the mortars mixed with 1% TIPA could reach 196%, 179%, 160% and 110% respectively, and the mortar strength after 3 d exceeded that of the contrast sample cured at 20 ℃. Under low temperature condition, TIPA could promote the hydration reaction of cement, shorten the induction period and advance the acceleration period. Furthermore, the maximum heat release rate and cumulative heat release quantity would be all increased, and the cumulative heat release of the cement mixed with TIPA hydrated for 12 h and 7 d increased 73% and 38% respectively. TIPA could shorten the nucleation and crystal growth (NG) stage and increase its hydration degree significantly, so it promoted cement hydration reaction. Additionally, the hydration reaction rates in phase boundary reaction (I) phase and diffusion reaction (D) phase were increased, and the duration of I process was prolonged, thereby the development of specimen strength would be accelerated. TIPA did not obviously change the types of hydration products, but increased the content of Ca(OH)2 in the samples and the degree of cement hydration. After hydration to 7 d, large amounts of hydration products, whose surface was smooth, were formed and bonded into sheets, and the structural density of samples improved significantly.

关键词： low temperature triisopropanolamine compressive strength hydration mechanism

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Prelude

Science China(Physics,Mechanics & Astronomy) 2013年第12期56卷 2240-2242页

作者： bai yin ZHAI JianLei SHI YongJiu WANG YuanQing School of Transportation Science and Engineering Beijing University of Aeronautics and Astronautics Department of Civil Engineering Key Laboratory of Structural Engineering and Vibration of China Education MinistryTsinghua University

This year we celebrate the 85th anniversary of the Institute of Physics, Chinese Academy of Sciences （CAS）. As an academic institution, the publication of a special issue dedicated to demonstrating the range and depth of researches it covers in the past few years is undoubtedly an appropriate way of celebration. I thank the journal Science China-Physics, Mechanics ＆ As- tronomy for providing us, with friendliness and generosity, their valuable pages. I would also take this opportunity to give a brief introduction to our institute and to highlight some important research results in the last several years.

关键词：物理研究所研究生院学术机构庆祝活动研究成果 CAS 物理学中国

Soil pH and dissolved organic carbon shape microbial communities in wetlands with two different vegetation types in Changdu area,Tibet

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Journal of Mountain Science 2023年第3期20卷 750-764页

作者： ZOU Lan bai yin-ping HUANG Jing XIAO De-rong YANG Gang School of Life Science and Engineering Southwest University of Science and TechnologyMianyang 621010China College of Life and Environmental Science Wenzhou UniversityWenzhou 325035China State&Local Joint Engineering Research Center for Ecological Treatment Technology of Urban Water Pollution Wenzhou UniversityWenzhou 325035China

Soil microorganisms play pivotal roles in element biogeochemical cycling and ecological functions in wetland ecosystem,which may affect global climate *** in biotic and abiotic factors are known to affect soil microbial diversity,community structure and the corresponding ***,the relative importance of these biotic and abiotic factors on wetland soil microbial diversity and community structure on the QinghaiTibet Plateau remains poorly *** this study,we explored soil bacterial and fungal diversity and composition of five wetlands under two vegetation types(herbs vs Hippophae thibetana)in Changdu area,Tibet,through Illumina high throughput sequencing analysis of 16S rRNA for bacteria and internal transcribed spacer(ITS)for *** showed that soil bacterial alpha diversity was higher in *** dominated wetlands and was significantly and positively correlated with soil *** difference was detected in the soil fungal alpha diversity among samples and between vegetation *** dominant soil bacterial phyla were Proteobacteria,Actinobacteria,Acidobacteria,and *** Ascomycota,Basidiomycota and Mucoromycota were the dominant fungal *** bacterial and fungal community structures were significantly distinct by vegetation *** addition,redundancy analysis indicated that soil pH was the key factor shaping soil bacterial community ***,soil p H showed no effect on fungal ***,soil dissolved organic carbon was the major factor contributing to soil fungal community *** study emphasized that wetland soil microbial communities were distinct by vegetation types and the driving factors of microbial beta diversity between bacterial and fungal community were also different in wetlands in Changdu area.

关键词： SoilPproperty Microbialdiversity Bacterial community Fungal community Hippophae thibetana Qinghai-Tibet Plateau

Wave Equation Decomposition in 3-D TTI Media

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石油地球物理勘探 2009年第A2期44卷 21-30页

作者： Liang Kai Wu Guo-chen yin Xing-yao bai Xiao-yin College of Geo-Resources and Information China University of Petroleum (East China) Dongying Shandong Province 257061 China Northwest Branch Research Institute of Petroleum Exploration and Development PetroChina Lanzhou Gansu Province 730020 China

Solvent-free Reactions of Formylferrocene with Active Methylene Containing Compounds

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有机化学 2003年第Z1期23卷 286-287页

作者： bai yin-Juan GAN Hai-ying LU Jun SHI Zhen Department of Chemistry Northwest University Xi''an 710069 Department of Chemistry Northwest University Xi''an 710069 Department of Chemistry Northwest University Xi''an 710069 Department of Chemistry Northwest University Xi''an 710069

　　Since ferrocene was synthesized, derivatives of ferrocene have attracted the attention of chemists, and recently solvent-free organic reaction has been an important new dimension in preparative organic chemistry. [1] Solventless synthesis without the use of supporting reagents which can avoid the risk of high pressure development and volatile toxic solvent employment is very amaizing and eco-friendly.……

关键词： organic chemistry organic reaction high pressure

Barrier-focused intervention to increase colonoscopy attendance among nonadherent high-risk populations

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World Journal of Gastroenterology 2009年第31期15卷 3920-3925页

作者： Wen Meng Xi-Wen Bi Xiao-yin bai Hua-Feng Pan Shan-Rong Cai Qi Zhao Su-Zhan Zhang Key Laboratory of Cancer Prevention and Intervention China National Ministry of Education Key Laboratory of Molecular Biology in Medical Sciences Zhejiang Province China The Second Affiliated Hospital Zhejiang University School of Medicine Hangzhou 310009 Zhejiang Province China Department of Cardiothoracic Surgery Hangzhou No. 1 People Hospital Hangzhou 310006 Zhejiang Province China Xiacheng District Center for Disease Control and Prevention Hangzhou 310003 Zhejiang Province China

AIM： To increase attendance tor colonoscopy among nonadherent high-risk individuals for colorectal cancer （CRC） screening in China. METHODS： During the first 12 mo without intervention, only 428 of the 2398 high-risk subjects attended a scheduled colonoscopy examination. The 1970 subjects who did not attend for CRC screening were enrolled in the present study. Prior barrier investigation was performed to ascertain the reasons for nonadherence. A barrier-focused intervention program was then established and implemented among eligible nonadherent subjects by telephone interviews and on-site consultations. The completion rates of colonoscopy during the first 12 mo without intervention and the second 12 mo with intervention were compared. Variations in the effect of the intervention on some high-risk factors and barrier characteristics were analyzed using logistic regression. RESULTS： 540 subjects who were not eligible were excluded from the study. The colonoscopy attendance rate was 23.04% （428/1858） during the first 12 mo without intervention, and 37.69% （539/1430） during the second 12 mo with intervention （P 〈 0.001）. Logistic regression analysis showed that the intervention was more effective among subjects with only objective barriers （OR： 34.590, 95% CI： 23.204-51.563） or subjects with some specific highrisk characteristics： first-degree relatives diagnosed with CRC （OR： 1.778, 95% CI： 1.010-3.131）, personal history of intestinal polyps （OR： 3.815, 95% CI： 1.994-7.300） and positive result for immunochemical fecal occult blood testing （OR： 2.718, 95% CI： 1.479-4.996）. CONCLUSION： The barrier-focused telephone or on- site consultation intervention appears to be a feasible means to improve colonoscopy attendance among nonadherent high-risk subjects for CRC screening in China.

关键词： Colorectal cancer Screening Intervention Colonoscopy Attendance

Diabetes mellitus in patients with type 1 autoimmune pancreatitis at diagnosis and after corticosteroid therapy

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Hepatobiliary & Pancreatic Diseases International 2024年第4期23卷 393-398页

作者： Mei-Zi Li Tao Guo Yun-Lu Feng Sheng-Yu Zhang Xiao-yin bai Xi Wu Kai Xu Ai-Ming Yang Department of Gastroenterology State Key Laboratory of Complex Severe and Rare DiseasesPeking Union Medical College HospitalPeking Union Medical College and Chinese Academy of Medical SciencesBeijing 100730China Department of Radiology Peking Union Medical College HospitalPeking Union Medical College and Chinese Academy of Medical SciencesBeijing 100730China

Background:A high prevalence of diabetes mellitus(DM)coexisting with autoimmune pancreatitis(AIP)is ***,evidence on the circumstances under which corticosteroid therapy(CST)for AIP improves or worsens DM is *** study aimed to demonstrate and identify predictors of DM control under the influence of ***:Patients diagnosed with type 1 AIP were enrolled from a prospectively maintained cohort and were classified into three groups according to the chronology in which AIP and DM were diagnosed:pre-existing DM(pDM),concurrent DM(cDM),and non-DM(nDM).The responses of DM to CST were assessed when corticosteroid was ceased or tapered to a maintenance dose and classified as‘improvement’and‘non-improvement’(including‘no change’and‘exacerbation’).Results:Among 101 patients with type 1 AIP,52(51.5%)patients were complicated with DM at the time of AIP diagnosis,with 36 patients in the cDM group and 16 patients in the pDM *** incidences of diffuse pancreatic swelling(72.2%)and pancreatic body/tail involvement(91.7%)were significantly higher in the cDM group than in both the pDM and nDM *** the 52 patients with DM,CST was administered in 48 *** logistic analysis identified that elevated serum gamma-glutamyl transferase(GGT)level at AIP diagnosis[odds ratio(OR)=0.032,95%confidence interval(CI):0.003-0.412,P=0.008]and pancreatic atrophy after CST(OR=0.027,95%CI:0.003-0.295,P=0.003)were negatively associated with DM control ***:Patients with diffuse pancreatic swelling and pancreatic body/tail involvement in pancreatitis tended to be complicated with cDM at AIP *** exerted a beneficial effect on the clinical course of DM in nearly half of the AIP patients complicated with DM at diagnosis,particularly in those without elevated serum GGT levels at diagnosis and who did not experience pancreatic atrophy after CST.

关键词： Type 1 autoimmune pancreatitis Diabetes mellitus Corticosteroid therapy Predictive factor Pancreatic atrophy