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Femtosecond laser-assisted astigmatic keratotomy: a review

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Eye and Vision 2018年第1期5卷 59-69页

作者： john s.M.Chang Department of Ophthalmology Hong Kong Sanatorium&Hospital8/FLi Shu Pui BlockPhase II2 Village RoadHappy ValleyHong KongChina

Background:Astigmatic keratotomy(AK)remains an accessible means to correct surgically induced or naturally occurring *** advantages of femtosecond laser-assisted astigmatic keratotomy(FsAK)over conventional methods have been recognized *** text:This review evaluates the efficacy,complications,and different methods of FsAK for correction of astigmatism in native eyes and those that underwent previous penetrating keratoplasty(PKP).The penetrating and intrastromal FsAK(IFsAK)techniques can reduce post-keratoplasty astigmatism by 35.4%to 84.77%and 23.53%to 89.42%,*** native eyes,the penetrating and IFsAK techniques reduce astigmatism by 26.8%to 58.62%and 36.3%to 58%respectively,implying that the magnitude of the astigmatic reduction is comparable between the two FsAK ***,IFsAK offers the additional advantages of almost no risk of infection,wound gape,and epithelial *** use of nomograms,anterior-segment optical coherence tomography,and consideration of posterior cornea and corneal biomechanics are helpful to enhance the efficacy and safety of *** complications of FsAK in eyes that underwent PKP include overcorrection,visual loss,microperforations,infectious keratitis,allograft rejection,and *** reported difficulties in native eyes include overcorrection,anterior gas breakthrough,and suction ***:In eyes that underwent PKP,FsAK effectively reduces high regular or irregular astigmatism,with rare and manageable ***,the drawbacks of the procedure include the potential loss of visual acuity and low *** native eyes undergoing femtosecond laser-assisted cataract surgery,IFsAK is a good choice to correct low astigmatism(s).The refractive effect of astigmatism from the posterior cornea needs to be considered in the nomograms for native eyes undergoing refractive cataract *** further improve the efficacy of FsAK,more large-scale ra

关键词： Femtosecond laser-assisted astigmatic keratotomy Post-keratoplasty astigmatism Astigmatism correction Refractive surgery

Advances in Laser and Light Based Technologies in Dermatology

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Advances in Laser and Light Based Technologies in Dermatolog...

The return of sherlock Holmes

中华医学会第十五次全国皮肤性病学术会议

作者： john Z.s.Chen Tucson Arizona USA

Ablative laser skin resurfacing with CO2 or Er-YAG laser systems is a well-accepted treatment for rhytides and photodamaged *** major disadvantage of this approach is the prolonged recovery *** side effects or complic...

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The return of Sherlock Holmes

Projection of Temperature-Related Excess Mortality by Integrating Population Adaptability Under Changing Climate—China,2050s and 2080s

作者： sir Arthur Conan Doyle with an introduction and notes by john s. Whitley.

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China CDC weekly 2021年第33期3卷 697-701,I0002-I0009页

作者： Zhiying sun Qing Wang Chen Chen Yang Yang Meilin Yan Hang Du Kai Chen john s.Ji Tiantian Li China CDC Key Laboratory of Environment and Population Health National Institute of Environmental HealthChinese Center for Disease Control and PreventionBeijingChina Institute of Environment and Health Tianjin Center for Disease Control and PreventionTianjinChina Institute of Urban Meteorology China Meteorological AdministrationBeijingChina school of Ecology and Environment Beijing Technology and Business UniversityBeijingChina Department of Environmental Health sciences Yale School of Public HealthNew HavenCTUSA Environmental Research Center Duke Kunshan UniversityDurhamNCUSA.&Joint first authors

What is already known about this topic?An increasing number of studies have projected temperature-related mortality,but few consider the change of population’s adaptability to future temperature and mortality burden from cold and heat *** is added by this report?This study offers a comprehensive characterization of human adaptability and excess mortality burden of temperature across various regions of *** are the implications for public health practice?The temperature-related excess mortality was projected to increase in the 2050s and decrease in the *** adaptability was projected to increase in the future,but along with the rising temperatures,the heatrelated excess mortality continuously rose,except for the low-speed rising *** the excess mortality of cold was projected to decrease in the nearer future,it might not keep declining in the long run,due to the decreasing cold-adaptability,which deserves more attention.

关键词： mortality excess adaptability

Mathematical modeling of microwave-assisted convective heating and drying of grapes

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International Journal of Agricultural and Biological Engineering 2008年第2期1卷 46-54页

作者： Gokhan Bingol Zhongli Pan john s.Roberts Y.Onur Devres Murat O.Balaban United states Department of Agriculture Agricultural Research ServiceWestern Regional Research CenterAlbanyCalifornia94710 USA Department of Biological and Agricultural Engineering University of CaliforniaDavisOne Shields Ave.Davis CA 95616 USA Istanbul Technical University Department of Food EngineeringIstanbul/Turkey34469 University of Florida FsHN Department GainesvilleFlorida32611 USA

This research studied the processing performance and product quality of Thompson seedless grapes dried using microwave-assisted convective hot air drying as well as the effect of blanching and dipping *** pretreatment methods were compared,dipping into 2%ethyl oleate(V/V)and 5%potassium carbonate solution(m/V)at 40℃for 3 minutes and steam blanching at 90℃for 140 s,to accelerate drying rate and inactivate PPO aiming to improve drying rate and product *** grapes were dried in a microwave-assisted convective dryer at 0.25 W/g specific power and 60℃air *** this study dielectric and physical properties of grapes were calculated using descriptive equations for fruits and ***-theoretical models were used to describe the drying curves of both pretreated and untreated *** and near surface temperature profile of grapes was obtained using fiber optic *** center temperature was modeled using one dimensional heat equation and was simulated using Partial Differential Equation toolbox of *** results showed that the maximum difference between experimental and predicted values were 4℃which occurred at the initial heating up *** has been observed that dipping into solution had no effect on drying rate whereas steam blanching significantly reduced the drying time and produced product with desirable color.

关键词： Microwave drying grapes mathematic modeling thin-layer curve fitting

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爆轰波三波点擦除烟迹表面积碳机制

工程科学学报 2017年第3期39卷 335-341页

作者：赵焕娟 john H.s.Lee 张英华严屹然北京科技大学土木与资源工程学院北京100083 Mechanical Engineering Department McG ill University

为理解三波点在壁面及端面积碳留下记录的确切机制,推动对螺旋爆轰内部结构的研究,采用端面烟熏玻璃与内壁烟膜结合的实验方法记录胞格结构,并得到不稳定、较稳定及稳定预混气的侧壁及端面爆轰记录.2H2+O2+3Ar给出了清晰精细的端面结果... 详细信息

为理解三波点在壁面及端面积碳留下记录的确切机制,推动对螺旋爆轰内部结构的研究,采用端面烟熏玻璃与内壁烟膜结合的实验方法记录胞格结构,并得到不稳定、较稳定及稳定预混气的侧壁及端面爆轰记录.2H2+O2+3Ar给出了清晰精细的端面结果,其单头螺旋结果表明相对于结果近似的侧壁结果,内部螺旋结构并非固定.进而从附着碳粒的粒度尺寸分析出碳迹附着原理并结合五种预混气的反应特性,确定键能足以克服碳迹吸附在表面的力时才能擦除烟迹.另外预混气中的碳分子也会导致烟迹堆积而影响端面结果,反射激波的强度也影响记录的清晰度.最终确定烟迹擦除机制受预混气影响,应针对预混气选用表面粗糙度载体和积碳颗粒尺寸,并给出了记录爆轰结构的方法.

关键词：螺旋爆轰烟膜烟熏玻璃三波点胞格结构

studies on electroless Ni-P-Cr_2O_3 and Ni-P-siO_2 composite coatings

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电镀与涂饰 2007年第1期26卷 1-6页

作者： KARTHIKEYAN s sRINIVAsAN K N VAsUDEVAN T john s National Engineering College K.R.NagarKovilpatti-628503TamilnaduIndia Central Electrochemical Research Institute Karaikudi-630006India Alagappa University Karaikudi-630003India

本文对化学镀镍及化学镀镍磷基质中siO2与Cr2O3的共沉积进行了研究。微粒在不断生长的膜层中共沉积引起了新的化学复合镀层的出现,这些复合镀层许多都具有优异的耐磨及耐蚀性能。通过选取镀层合金/复合微粒/金属基体的组分可改进镀层,... 详细信息

本文对化学镀镍及化学镀镍磷基质中siO2与Cr2O3的共沉积进行了研究。微粒在不断生长的膜层中共沉积引起了新的化学复合镀层的出现,这些复合镀层许多都具有优异的耐磨及耐蚀性能。通过选取镀层合金/复合微粒/金属基体的组分可改进镀层,获得所需的性能,以满足特别的需求。在对这些复合镀层的应用需求正在迫近与增长的同时,其市场正在迅速扩张。本文开发出了一种合适的复合化学镀镍液,并通过维氏硬度法对化学复合镀镍层进行了表征。采用动电位极化及交流阻抗法测定了镀层的Taber耐磨性能及耐蚀性能。采用sEM及XRD对复合镀层的表面形貌进行了分析。

关键词：化学镀镍化学复合镀层siO2 Cr2O3 共沉积维氏硬度法动电位极化交流阻抗

Validation of a discrete element model using magnetic resonance measurements

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Particuology 2009年第4期7卷 297-306页

作者： Christoph R.Müller stuart A.scott Daniel J.Holland Belinda C.Clarke Andrew J.sederman john s.Dennis Lynn F.Gladden Department of Chemical Engineering and Biotechnology University of CambridgePembroke StreetCambridge CB2 3RAUnited Kingdom

The discrete element model （DEM） is a very promising modelling strategy for two-phase granular systems. However, owing to a lack of experimental measurements, validation of numerical simulations of two-phase granular systems is still an important issue. In this study, a small two-dimensional gas- fluidized bed was simulated using a discrete element model. The dimensions of the simulated bed were 44mm × 10mm × 120 mm and the fluidized particles had a diameter dp = 1.2 mm and density ρp = 1000 kg/m^3. The comparison between DEM simulations and experiments are performed on the basis of time-averaged voidage maps. The drag-law of Beetstra et al. [Beetstra, R., van der Hoef, M.A., ＆ Kuipers,J. A. M. （2007b）. Drag force of intermediate Reynolds number flow past mono- and bidispersed arrays of spheres. AIChE Journal, 53,489-501 ] seems to give the best results. The simulations are fairly insensitive to the coefficient of restitution and the coefficient of friction as long as some route of energy dissipation during particle-particle and particle-wall contact is provided. Changing the boundary condition of the gas phase at the side-walls from zero-slip to full-slip does not affect the simulation results. Care is to be taken that the cell sizes are chosen so that a reasonable number of particles can be found in a fluid cell.

关键词： Discrete element modelling Magnetic resonance imaging Voidage Gas-fluidized beds

semi-stable distributions in free probability theory

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science China Mathematics 2006年第3期49卷 387-397页

作者： shandong University, Ji’nan 250100, China Department of Mathematics and statistics, Memorial University of Newfoundland, HH 3050, st. john’s, A1C 5s7, Canada shandong University Ji’nan China Department of Mathematics and statistics Memorial University of Newfoundland St. John’s Canada

semi-stable distributions, in classical probability theory, are characterized as limiting distributions of subsequences of normalized partial sums of independent and identically distributed random variables. We establish the noncommutative counterpart of semi-stable distributions. We study the characterization of noncommutative semi-stability through free cumulant transform and develop the free semi-stability and domain of semi-stable attraction in free probability theory.

关键词： stable distributions, semi-stable distributions, noncommutative random vari-ables, Voiculescu transform, free cumulant transform.