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Nuclear Science and Techniques 2024年第3期35卷 40-52页

作者： Ding-Han Zhu Xiong Zhang Xiao-Qiang Li Peng Li yan-bin wang Shuang Zhang State Key Laboratory of NBC Protection for Civilian Beijing 102205China

In high-altitude nuclear detonations,the proportion of pulsed X-ray energy can exceed 70%,making it a specific monitoring signal for such *** pulsed X-rays can be captured using a satellite-borne X-ray detector following atmospheric *** quantitatively analyze the effects of different satellite detection altitudes,burst heights,and transmission angles on the physical processes of X-ray transport and energy fluence,we developed an atmospheric transmission algorithm for pulsed X-rays from high-altitude nuclear detonations based on scattering *** proposed method is an improvement over the traditional analytical method that only computes direct-transmission *** traditional analytical method exhibits a maximum relative error of 67.79% compared with the Monte Carlo *** improved method reduces this error to within 10% under the same conditions,even reaching 1% in certain ***,its computation time is 48,000 times faster than that of the Monte Carlo *** results have important theoretical significance and engineering application value for designing satellite-borne nuclear detonation pulsed X-ray detectors,inverting nuclear detonation source terms,and assessing ionospheric effects.

关键词： High-altitude nuclear detonation Atmospheric transmission Pulsed X-rays Scattering correction Analytical method Monte Carlo method

Synthesis and mesomorphic properties of new azine-type liquid crystals

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Chinese Chemical Letters 2007年第5期18卷 527-529页

作者： Qiang Wei Lin Shi Hui Cao Huai yang yan bin wang Department of Materials Physics and Chemistry School of Materials Science and Engineering University of Science and Technology Beijing Beijing 100083 China

A series of symmetrical azine-type liquid crystals were synthesized. The characteristic of these liquid crystals is that they had high clearing point （～320℃） and broad thermal range of nematic phase （～154℃）. I... 详细信息

关键词： Liquid crystal Symmetrical azine Synthesis Mesomorphic properties

Long-term follow-up study of elderly patients with covered stent implantation after coronary perforation

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Journal of Geriatric Cardiology 2014年第3期11卷 218-221页

作者： Geng wang Ya-Ling HAN Quan-Min JING Xiao-Zeng wang Ying-yan MA bin wang Department of Cardiology Shenyang Northern Hospital Shenyang 110016 Liaoning Province China

ObjectiveTo evaluate the long-term efficacy of covered stent implantation in the treatment of elderly patients with coronary perforation while undergoing percutaneous coronary intervention （PCI）.MethodsFrom June 2004 to June 2012, our center has followed ten elderly patients （age≥ 60 years） who sustained coronary perforation during PCI. The major adverse cardiac events （MACE） were observed as well. The patients were advised to take 75 mg/day Clopidogrel for two years, and indefinite use of 100 mg/day enteric-coated *** out of the 10 patients aged from 60 to 76 years old （mean 68.6 ± 5.2 years） were male, four were female. The average diameter of the implanted stents was 3.3 ± 0.3 mm, and the average length was 22.1 ± 3.7 mm. All the ruptures were successfully sealed without intra-procedural death. The follow-up duration ranged from 0.6 to 67 months （mean 31.7 ± 24.5 months）. One patient died of multiple organ failure due to lung infection in 19 days after PCI; one died of cardiac sudden death in 13 months after PCI; one had angina pectoris in 53 months after PCI; one underwent multi-slice CT examination in six months after PCI, and no in-stent restenosis was found. The other four patients received angiography follow-up, and the results showed that three patients had no intra-stent restenosis, while one had left anterior descending （LAD） restenosis in the covered stent in 67 months after PCI. The in-hospital mortality was 10% （1/10）. The MACE rate in 12 months after PCI was 10% （1/10）. During the entire followed-up period, the restenosis rate in target vessels was 20% （1/5）, mortality was 20% （2/10）, and the MACE rate was 40% （4/10）.ConclusionTreatment of coronary perforation by using covered stents can achieve favorable long-term results; a two-year dual antiplatelet therapy （DAPT） after PCI can effectively prevent intra-stent thrombosis.

关键词： Coronary perforation Percutaneous coronary intervention Covered stent

Influence of Annealing Treatments on Microstructure and Mechanical Properties of an Extruded Mg AZ31/Al 7050 Laminate

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Acta Metallurgica Sinica(English Letters) 2019年第2期32卷 227-234页

作者： yang Wu Yun-Chang Xin Xiang-Sheng Xia Bo Feng yan-bin wang Zu-De Zhao Southwest Technology and Engineering Research Institute International Joint Laboratory for Light Alloys College of Materials Science and Engineering Chongqing University Guangdong Institute of Materials and Processing Guangdong Academy of Sciences

Mg AZ31/A1 7050 laminate was fabricated by co-extrusion directly from the as-cast Mg AZ31 and Al 7050 billets. The influence of annealing temperature and annealing time on microstructure and mechanical behavior of the extruded Mg/Al laminate was systematically studied. Results show that annealing treatments at 250 ℃ for 3 h or at 350 ℃ for 3 h do not result in an obvious grain coarsening of Mg layer and cannot remove the heterogeneous structure. Annealing does not vary texture in the Mg layer, a large fraction of //ND and a small fraction of //TD, but the intensity of component //ND weakens to some extent. Lamellar microstructure in the A1 layer remains after annealing at250 ℃ for 3 h or at 350 ℃ for 3 h. High fractions of the texture components S and cube exist in the extruded sample, and annealing treatment hardly changes their fractions. Post-annealing treatment will largely reduce yield strength of extruded plate and increase plasticity slightly. The yield strength drops from 302 MPa to 206 MPa after annealing at 250 ℃ for 3 h and to 141 MPa after annealing at 350 ℃ for 3 h. The elongation to fracture increases from 1.5% to 5.4% after annealing at 250 ℃ for 3 h and to 4.8% at 350 ℃ for 3 h. The corresponding mechanism was discussed.

关键词： Laminate composite Annealing Microstructure Texture Mechanical property

Ratiometric and selective two-photon fluorescent probe based on PET-ICT for imaging Zn^(2+)in living cells and tissues

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Chinese Chemical Letters 2014年第1期25卷 93-98页

作者： Shang Wu Ya-Jun Wei yan-bin wang Qiong Su Lan Wu Hong Zhang Fen-Ping Yin Pei-Lin Yuan College of Chemical EngineeringNorthwest University for Nationalities

A two-photon fluorescent probe TPZn was developed for specific ratiometric imaging Zn2＋ in living cells and tissues. Significant ratiometric fluorescence change was based on photoinduced electron transfer and intramolecular charge transfer. The synthetic method of TPZn was simple. It was successfully used to selectively image Zn2＋ based on the higher binding affinity for Zn2＋ than for Cd2＋. TPZn was easily loaded into the living cell and tissues with high membrane permeability in a complex biological environment. TPZn could clearly visualize endogenous Zn2＋ by TP ratiometric imaging in hippocampal slices at a depth of 120 μm. Thus, TPZn is a useful tool to image of Zn2＋ in living cells and tissues without interference from Cd2＋.

关键词： Two-photon probe Ratiometric fluorescent imaging ZincLiving cell Living tissue

Digital single-operator cholangioscopy for biliary stricture after cadaveric liver transplantation

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World Journal of Gastrointestinal Oncology 2022年第5期14卷 1037-1049页

作者： Jian-Feng Yu Dong-Lei Zhang yan-bin wang Jian-Yu Hao Department of Gastroenterology Beijing Chao-Yang HospitalCapital Medical UniversityBeijing 100020China

BACKGROUND Biliary strictures after liver transplantation(LT)remain clinically arduous and challenging situations,and endoscopic retrograde cholangiopancreatography(ERCP)has been considered as the gold standard for the management of biliary strictures after ***,in the treatment of biliary strictures after LT with ERCP,many studies show that there is a large variation in diagnostic accuracy and therapeutic success *** single-operator peroral cholangioscopy(DSOC)is considered a valuable diagnostic modality for indeterminate biliary *** To evaluate DSOC in addition to ERCP for management of biliary strictures after *** Nineteen patients with duct-to-duct biliary reconstruction who underwent ERCP for suspected biliary complications between March 2019 and March 2020 at Beijing Chaoyang Hospital,Capital Medical University,were consecutively enrolled in this observational *** evaluating bile ducts using fluoroscopy,cholangioscopy using a modern digital single-operator cholangioscopy system(SpyGlass DS^(TM))was performed during the same procedure with patients under conscious *** patients received peri-interventional antibiotic *** strictures after LT were classified according to the manifestations of choledochoscopic strictures and the manifestations of transplanted hepatobiliary *** Twenty-one biliary strictures were found in a total of 19 patients,among which anastomotic strictures were evident in 18(94.7%)patients,while non-anastomotic strictures in 2(10.5%),and space-occupying lesions in 1(5.3%).Stones were found in 11(57.9%)and loose sutures in 8(42.1%).A benefit of cholangioscopy was seen in 15(78.9%)*** was crucial for selective guidewire placement prior to planned intervention in 4 *** was instrumental in identifying biliary stone and/or loose sutures in 9 patients in whom ERCP *** also provided a direct vision for laser lithotripsy.A spaceoccupying l

关键词： Cholangioscopy Endoscopic retrograde cholangiopancreatography Liver transplantation Biliary strictures Biliary complications Biliary anastomotic stricture

Effect of enalapril on plasma homocysteine levels in patients with essential hypertension

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2010年第8期11卷 583-591页

作者： Fang-fang FAN Yong HUO Xu wang Xin XU bin-yan wang Xi-ping XU Jian-ping LI Department of Cardiology Peking University First Hospital Beijing 100034 China Institute of Biomedicine Anhui Medical University Hefei 230032 China

Objective:To investigate the effect of enalapril on plasma homocysteine(Hcy) levels and the association of methylenetetrahydrofolate reductase(MTHFR) C677T polymorphism with the changes of Hcy levels in response to enalapril among patients with essential ***:A total of 130 patients with mild-to-moderate essential hypertension were enrolled and enalapril was orally administered at a dose of 10 mg/d for eight *** Hcy levels were measured by denaturing high-performance liquid chromatography(DHPLC) at baseline and after eight weeks of *** of MTHFR C677T polymorphism was performed by TaqMan probe ***:Compared with baseline,plasma Hcy levels did not change significantly after eight weeks(P=0.81).Stratified by baseline Hcy levels,a significant increase in plasma Hcy levels(P=0.02) among those with Hcy <10 μmol/L was observed,in contrast to no significant changes in plasma Hcy levels(P=0.54) among those with Hcy ≥10 μmol/*** significant association was observed between MTHFR C677T polymorphism and changes in Hcy levels in response to ***:Enalapril may cause an increase in plasma Hcy levels among the hypertensives with low baseline Hcy *** was no significant association between MTHFR C677T genotypes and changes in Hcy levels in response to enalapril among subjects with essential hypertension.

关键词： Essential hypertension Methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism Enalapril Homocysteine

Self-starting all-fiber PM Er:laser mode locked by a biased nonlinear amplifying loop mirror

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Chinese Physics B 2019年第12期28卷 160-164页

作者： Ke Yin Yi-Ming Li yan-bin wang Xin Zheng Tian Jiang National Innovation Institute of Defense Technology Academy of Military Sciences PLA ChinaBeijing 100071China College of Advanced Interdisciplinary Studies National University of Defense TechnologyChangsha 410073China State Key Laboratory of High Performance Computing College of ComputerNational University of Defense TechnologyChangsha 410073China Luoyang Electronic Equipment Test Center of China Luoyang 471003China

A compact all-fiber polarization-maintaining Er:laser using a nonlinear amplifying loop mirror is reported. Fundamental single-pulse mode-locking operation can always self start, with a cavity round-trip decreased from ~ 4.7 m to~ 1.7 m. When the pulse repetition rate is 121.0328 MHz, output pulse is measured to have a center wavelength/3-d B spectral bandwidth/radio frequency signal to noise ratio(SNR)/pulse width of 1571.65 nm/18.70 nm/80 d B/477 fs, respectively. Besides, three states including the exponential growth, damping state, and steady state are investigated through the build-up process both experimentally and numerically. Excellent stability of this compact Er:laser is further evaluated,demonstrating that it can be an easy-fabrication maintenance-free ultrafast candidate for the scientific area of this kind.

关键词： ultrafast fiber laser single-mode polarization-maintaining Er:laser

Effect of boron addition on the microstructure and stress-rupture properties of directionally solidified superalloys

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International Journal of Minerals,Metallurgy and Materials 2014年第11期21卷 1120-1126页

作者： Bao-ping Wu Lin-han Li Jian-tao Wu Zhen wang yan-bin wang Xing-fu Chen Jian-xin Dong Jun-tao Li School of Materials Science and Engineering University of Science and Technology Beijing Central Iron & Steel Material Research Institute

This study is focused on the effect of boron addition, in the range of 0.0007wt% to 0.03wt%, on the microstructure and stress-rupture properties of a directionally solidified superalloy. With increasing boron content in the as-cast alloys, there is an increase in the fraction of the γ′/γ eutectic and block borides precipitate around the γ′/γ eutectic. At a high boron content of 0.03wt%, there is precipitation of lamellar borides. Upon heat treatment, fine block borides tend to precipitate at grain boundaries with increasing boron content. Overall, the rupture life of the directionally solidified superalloy is significantly improved with the addition of nominal content of boron. However, the rupture life decreases when the boron content exceeds 0.03wt%.

关键词： superalloys directional solidification microstructure boron stress-rupture properties

Microstructure and stress rupture properties of polycrystal and directionally solidified castings of nickel-based superalloys

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International Journal of Minerals,Metallurgy and Materials 2014年第1期21卷 58-64页

作者： Bao-ping Wu Lin-han Li Jian-tao Wu Zhen wang yan-bin wang Xing-fu Chen Jian-xin Dong Jun-tao Li Central Iron & Steel Material Research Institute School of Materials Science and Engineering University of Science and Technology Beijing

A new directionally solidified Ni-based superalloy DZ24, which is a modification of K24 alloy without rare and expensive elemental additions, such as Ta and Hf, was studied in this paper. The microstructure and stress rupture properties of conventionally cast and directionally solidified superalloys were comparatively analyzed. It is indicated that the microstructure of K24 alloy is composed of γ, γ＇, γ/γ＇ eutectics and MC carbides. Compared with the microstructure of K24 polycrystalline alloy, γ/γ＇ eutectic completely dissolves into the γ matrix, the fine and regular γ＇ phase reprecipitates, and MC carbides decompose to M6C/M23C6 carbides after heat treatment in DZ24 alloy. The rupture life of DZ24 alloy is two times longer than that of K24 alloy. The more homogeneous the size of γ＇ precipitate, the longer the rupture life. The coarsening and rafting behaviors of γ＇ precipitates are observed in DZ24 alloy after the stress-rupture test.

关键词： superalloys nickel alloys microstructure precipitation carbides mechanical properties