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Shape and diffusion instabilities of two non-spherical gas bubbles under ultrasonic conditions
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作者 包乌日汗 王德鑫 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期715-721,共7页
Ultrasonic cavitation involves dynamic oscillation processes induced by small bubbles in a liquid under the influence of ultrasonic waves. This study focuses on the investigation of shape and diffusion instabilities o... Ultrasonic cavitation involves dynamic oscillation processes induced by small bubbles in a liquid under the influence of ultrasonic waves. This study focuses on the investigation of shape and diffusion instabilities of two bubbles formed during cavitation. The derived equations for two non-spherical gas bubbles, based on perturbation theory and the Bernoulli equation, enable the analysis of their shape instability. Numerical simulations, utilizing the modified Keller–Miksis equation,are performed to examine the shape and diffusion instabilities. Three types of shape instabilities, namely, Rayleigh–Taylor,Rebound, and parametric instabilities, are observed. The results highlight the influence of initial radius, distance, and perturbation parameter on the shape and diffusion instabilities, as evidenced by the R_0–P_a phase diagram and the variation pattern of the equilibrium curve. This research contributes to the understanding of multiple bubble instability characteristics, which has important theoretical implications for future research in the field. Specifically, it underscores the significance of initial bubble parameters, driving pressure, and relative gas concentration in determining the shape and diffusive equilibrium instabilities of non-spherical bubbles. 展开更多
关键词 non-spherical bubble shape instability diffusive instability
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Flow Behaviors of Non-spherical Granules in Rectangular Hopper 被引量:7
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作者 JIN Baosheng TAO He ZHONG Wenqi 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2010年第6期931-939,共9页
Flow behaviors of four kinds of granular particles(i.e. sphere,ellipsoid,hexahedron and binary mixture of sphere and hexahedron) in rectangular hoppers were experimentally studied. The effects of granular shape and ho... Flow behaviors of four kinds of granular particles(i.e. sphere,ellipsoid,hexahedron and binary mixture of sphere and hexahedron) in rectangular hoppers were experimentally studied. The effects of granular shape and hopper structure on flow pattern,discharge fraction,mean particle residence time and tracer concentration distribu-tion were tested based on the visual observation and particle tracer technique. The results show that particle shape affects significantly the flow pattern. The flow patterns of sphere,ellipsoid and binary mixture are all parabolic shape,and the flow pattern shows no significant difference with the change of wedge angle. The flowing zone be-comes more sharp-angled with the increasing outlet size. The flow pattern of hexahedron is featured with straight lines. The discharge rates are in increasing order from hexahedron,sphere,binary mixture to ellipsoid. The dis-charge rate also increases with the wedge angle and outlet size. The mean particle residence time becomes shorter when the outlet size increases. The difference of mean particle residence time between the maximum and minimum values decreases as the wedge angle increases. The residence time of hexahedron is the shortest. The tracer concen-tration distribution of hexahedron at any height is more uniform than that of binary mixture. The tracer concentra-tion of sphere in the middle is lower than that near the wall,and the contrary tendency is found for ellipsoid particles. 展开更多
关键词 non-spherical particle flow behavior rectangular hopper wedge angle
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Preparation of Non-spherical Colloidal Silica Nanoparticle and Its Application on Chemical Mechanical Polishing of Sapphire 被引量:4
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作者 KONG Hui LIU Weili 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2019年第1期86-90,共5页
Non-spherical colloidal silica nanoparticle was prepared by a simple new method, and its particle size distribution and shape morphology were characterized by dynamic light scattering(DLS) and the Focus Ion Beam(FIB) ... Non-spherical colloidal silica nanoparticle was prepared by a simple new method, and its particle size distribution and shape morphology were characterized by dynamic light scattering(DLS) and the Focus Ion Beam(FIB) system. This kind of novel colloidal silica particles can be well used in chemical mechanical polishing(CMP) of sapphire wafer surface. And the polishing test proves that non-spherical colloidal silica slurry shows much higher material removal rate(MRR) with higher coefficient of friction(COF) when compared to traditional large spherical colloidal silica slurry with particle size 80 nm by DLS. Besides, sapphire wafer polished by non-spherical abrasive also has a good surface roughness of 0.460 6 nm. Therefore, non-spherical colloidal silica has shown great potential in the CMP field because of its higher MRR and better surface roughness. 展开更多
关键词 COLLOIDAL silica NANOPARTICLE non-spherical chemical mechanical POLISHING SAPPHIRE WAFER
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Mechanism study of producing non-spherical powder in gas atomization 被引量:3
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作者 施立新 李强 《China Welding》 EI CAS 2013年第2期60-66,共7页
Gas atomization was usually regarded as a good method for producing the spherical or approximate spherical powders. We found a lot of non-spherical powders in production processes, especially in larger particle size d... Gas atomization was usually regarded as a good method for producing the spherical or approximate spherical powders. We found a lot of non-spherical powders in production processes, especially in larger particle size distribution area. The causes of producing non-spherical powders are explained and some analyses are done in order to find a better condition of producing spherical powders in this paper. The following morphologies were obtained by atomized Fe50 Co50 and pure iron and investigated by scanning electron microscopy (SEM). 展开更多
关键词 MORPHOLOGY non-spherical POWDER ATOMIZATION
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Distribution of non-spherical nanoparticles in turbulent flow of ventilation chamber considering fluctuating particle number density 被引量:1
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作者 Ruifang SHI Jianzhong LIN +1 位作者 Hailin YANG MingzhouYU 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2021年第3期317-330,共14页
The Reynolds-averaged general dynamic equation(RAGDE)for the nanoparticle size distribution function is derived,including the contribution to particle coagulation resulting from the fluctuating concentration.The equat... The Reynolds-averaged general dynamic equation(RAGDE)for the nanoparticle size distribution function is derived,including the contribution to particle coagulation resulting from the fluctuating concentration.The equation together with that of a turbulent gas flow is solved numerically in the turbulent flow of a ventilation chamber with a jet on the wall based on the proposed model relating the fluctuating coagulation to the gradient of mean concentration.Some results are compared with the experimental data.The results show that the proposed model relating the fluctuating coagulation to the gradient of mean concentration is reasonable,and it is necessary to consider the contribution to coagulation resulting from the fluctuating concentration in such a flow.The changes of the particle number concentration M_(0) and the geometric mean diameter dg are more obvious in the core area of the jet,but less obvious in other areas.With the increase in the initial particle number concentration m00,the values of M_(0) and the standard deviation of the particle sizeσdecrease,but the value of d_(g) increases.The decrease in the initial particle diameter leads to the reduction of M_(0) andσand the increase in d_(g).With the increase in the Reynolds number,particles have few chances of collision,and hence the coagulation rate is reduced,leading to the increase in M_(0) andσand the decrease in d_(g). 展开更多
关键词 non-spherical nanoparticle fluctuating particle concentration ventilation chamber particle distribution
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Simulation on hydrodynamics of non-spherical particulate system using a drag coefficient correlation based on artificial neural network 被引量:1
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作者 Sheng-Nan Yan Tian-Yu Wang +2 位作者 Tian-Qi Tang An-Xing Ren Yu-Rong He 《Petroleum Science》 SCIE CAS CSCD 2020年第2期537-555,共19页
Fluidization of non-spherical particles is very common in petroleum engineering.Understanding the complex phenomenon of non-spherical particle flow is of great significance.In this paper,coupled with two-fluid model,t... Fluidization of non-spherical particles is very common in petroleum engineering.Understanding the complex phenomenon of non-spherical particle flow is of great significance.In this paper,coupled with two-fluid model,the drag coefficient correlation based on artificial neural network was applied in the simulations of a bubbling fluidized bed filled with non-spherical particles.The simulation results were compared with the experimental data from the literature.Good agreement between the experimental data and the simulation results reveals that the modified drag model can accurately capture the interaction between the gas phase and solid phase.Then,several cases of different particles,including tetrahedron,cube,and sphere,together with the nylon beads used in the model validation,were employed in the simulations to study the effect of particle shape on the flow behaviors in the bubbling fluidized bed.Particle shape affects the hydrodynamics of non-spherical particles mainly on microscale.This work can be a basis and reference for the utilization of artificial neural network in the investigation of drag coefficient correlation in the dense gas-solid two-phase flow.Moreover,the proposed drag coefficient correlation provides one more option when investigating the hydrodynamics of non-spherical particles in the gas-solid fluidized bed. 展开更多
关键词 Fluidized bed Two-fluid model Drag coefficient correlation non-spherical particle Artificial neural network
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Application of a Neural Network to Store and Compute the Optical Properties of Non-Spherical Particles 被引量:1
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作者 Jinhe YU Lei BI +1 位作者 Wei HAN Xiaoye ZHANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2022年第12期2024-2039,共16页
Radiative transfer simulations and remote sensing studies fundamentally require accurate and efficient computation of the optical properties of non-spherical particles.This paper proposes a deep learning(DL)scheme in ... Radiative transfer simulations and remote sensing studies fundamentally require accurate and efficient computation of the optical properties of non-spherical particles.This paper proposes a deep learning(DL)scheme in conjunction with an optical property database to achieve this goal.Deep neural network(DNN)architectures were obtained from a dataset of the optical properties of super-spheroids with extensive shape parameters,size parameters,and refractive indices.The dataset was computed through the invariant imbedding T-matrix method.Four separate DNN architectures were created to compute the extinction efficiency factor,single-scattering albedo,asymmetry factor,and phase matrix.The criterion for designing these neural networks was the achievement of the highest prediction accuracy with minimal DNN parameters.The numerical results demonstrate that the determination coefficients are greater than 0.999 between the prediction values from the neural networks and the truth values from the database,which indicates that the DNN can reproduce the optical properties in the dataset with high accuracy.In addition,the DNN model can robustly predict the optical properties of particles with high accuracy for shape parameters or refractive indices that are unavailable in the database.Importantly,the ratio of the database size(~127 GB)to that of the DNN parameters(~20 MB)is approximately 6810,implying that the DNN model can be treated as a highly compressed database that can be used as an alternative to the original database for real-time computing of the optical properties of non-spherical particles in radiative transfer and atmospheric models. 展开更多
关键词 non-spherical particles light scattering super-spheroid model deep learning neural network
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NUMERICAL SIMULATIONS OF POLARIZED SCATTERING FROM RANDOM CLUSTERS OF SPATIALLY-ORENTED, NON-SPHERICAL SCATTERS
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作者 Huang Xingzhong Jin Yaqiu(Department of Electronics Engineering Wave Scattering and Remote Sensing Centre, Aidan University, Shanghai 200433) 《Journal of Electronics(China)》 1998年第3期267-273,共7页
Employing multiple scattering formulation of T-matrix method, numerical simulations are developed and applied to polarized scattering from random clusters of spatially-oriented, non-spherical particles. Polarized scat... Employing multiple scattering formulation of T-matrix method, numerical simulations are developed and applied to polarized scattering from random clusters of spatially-oriented, non-spherical particles. Polarized scattering is numerically presented for the functional dependence on particle shape, size, spatial distribution and orientation, and other physical parameters. Numerical calculations of backscattering from randomly clustered particles are well compared with that from independent particles and clusters. It can be seen that spatial distribution and orientation of non-spherical particles can have significant effect on scattering. 展开更多
关键词 RANDOM distribution non-spherical PARTICLES Multiple SCATTERING
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Non-spherical particle mixing behaviors by spherical inert particles assisted in a fluidized bed
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作者 An-Xing Ren Tian-Yu Wang +1 位作者 Tian-Qi Tang Yu-Rong He 《Petroleum Science》 SCIE CAS CSCD 2020年第2期509-524,共16页
Fluidized beds are widely used in many industrial fields such as petroleum,chemical and energy.In actual industrial processes,spherical inert particles are typically added to the fluidized bed to promote fluidization ... Fluidized beds are widely used in many industrial fields such as petroleum,chemical and energy.In actual industrial processes,spherical inert particles are typically added to the fluidized bed to promote fluidization of non-spherical particles.Understanding mixing behaviors of binary mixtures in a fluidized bed has specific significance for the design and optimization of related industrial processes.In this study,the computational fluid dynamic-discrete element method with the consideration of rolling friction was applied to evaluate the mixing behaviors of binary mixtures comprising spherocylindrical particles and spherical particles in a fluidized bed.The simulation results indicate that the differences between rotational particle velocities were higher than those of translational particle velocities for spherical and non-spherical particles when well mixed.Moreover,as the volume fraction of the spherocylindrical particles increases,translational and rotational granular temperatures gradually increase.In addition,the addition of the spherical particles makes the spherocylindrical particles preferably distributed in a vertical orientation. 展开更多
关键词 non-spherical particle Fluidized bed Discrete element method Binary mixtures
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A CFD-DEM-Wear Coupling Method for Stone Chip Resistance of Automotive Coatings with a Rigid Connection ParticleMethod for Non-Spherical Particles
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作者 Jiacheng Qian Chenqi Zou +2 位作者 Mengyan Zang Shunhua Chen Makoto Tsubokura 《Computer Modeling in Engineering & Sciences》 SCIE EI 2022年第11期251-280,共30页
The stone chip resistance performance of automotive coatings has attracted increasing attention in academic and industrial communities.Even though traditional gravelometer tests can be used to evaluate stone chip resi... The stone chip resistance performance of automotive coatings has attracted increasing attention in academic and industrial communities.Even though traditional gravelometer tests can be used to evaluate stone chip resistance of automotive coatings,such experiment-based methods suffer from poor repeatability and high cost.The main purpose of this work is to develop a CFD-DEM-wear coupling method to accurately and efficiently simulate stone chipbehaviorof automotive coatings inagravelometer test.Toachieve this end,an approach coupling an unresolved computational fluid dynamics(CFD)method and a discrete element method(DEM)are employed to account for interactions between fluids and large particles.In order to accurately describe large particles,a rigid connection particle method is proposed.In doing so,each actual non-spherical particle can be approximately described by rigidly connecting a group of non-overlapping spheres,and particle-fluid interactions are simulated based on each component sphere.An erosion wear model is used to calculate the impact damage of coatings based on particlecoating interactions.Single spherical particle tests are performed to demonstrate the feasibility of the proposed rigid connection particle method under various air pressure conditions.Then,the developed CFD-DEM-wear model is applied to reproduce the stone chip behavior of two standard tests,i.e.,DIN 55996-1 and SAE-J400-2002 tests.Numerical results are found to be in good agreement with experimental data,which demonstrates the capacity of our developed method in stone chip resistance evaluation.Finally,parametric studies are conducted to numerically investigate the influences of initial velocity and test panel orientation on impact damage of automotive coatings. 展开更多
关键词 Automotive coating stone chip resistance gravelometer non-spherical particle composite particle CFD-DEM
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角膜光密度评价复性近视散光Trans-PRK术后haze特点1例
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作者 李帅飞 游昌涛 +1 位作者 徐玲玲 陈东栋 《实用防盲技术》 2024年第4期168-170,F0002,F0004,共5页
1例复性近视散光女性患者在经上皮准分子激光角膜表面切削(Trans-PRK)术后早期因发现怀孕停用糖皮质激素滴眼液,随访过程中出现角膜上皮下混浊(haze),并使用Pentacam眼前节分析仪测量角膜光密度进行haze程度和特点的评价。
关键词 Trans-PRK haze 角膜光密度 近视 散光
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Analysis of the Haze Weather Process in the East of China from January 21 to 28, 2021
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作者 Ruicheng Zhang 《Journal of Geoscience and Environment Protection》 2024年第7期130-138,共9页
Haze is a pollution weather phenomenon that has been widely concerned by people in recent years. It has a significant impact on people’s production, life, and health. This study focuses on large-scale haze weather th... Haze is a pollution weather phenomenon that has been widely concerned by people in recent years. It has a significant impact on people’s production, life, and health. This study focuses on large-scale haze weather that happened in eastern China in late January 2021. The research uses multi-party data and synoptic analysis methods to analyze the occurrence, evolution, and end of the haze weather. The polar vortex, the change of the atmospheric circulation, the change of the cold air force, the temperature and humidity, and the rain and snow weather are the important reasons for this weathering process. It can be used for reference in future research on haze weather. 展开更多
关键词 haze Forming Atmospheric Diffusion Conditions Eastern China
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Examining the Experiences and Challenges of Haze-Fog Governance in China
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作者 Renrui Wang 《Journal of Geoscience and Environment Protection》 2024年第4期45-58,共14页
With the rapid development of industrialisation and urbanisation, China is facing the challenge of severe HF (Haze-Fog) pollution. This essay compares the advantages and disadvantages of China’s HF management and sum... With the rapid development of industrialisation and urbanisation, China is facing the challenge of severe HF (Haze-Fog) pollution. This essay compares the advantages and disadvantages of China’s HF management and summarizes the important lessons China can teach the rest of the world about applying this tactic. China’s capabilities in the digital economy, National Innovation Demonstration Zones, and urban innovation systems are examined in this article, along with its shortcomings in information mechanisms and pollution sources. This essay also summarizes China’s achievements, particularly regarding local autonomy. The essay goes on to say, however, that China is probably going to be under more pressure to manage HF in the future, both in terms of long-term solutions and the economy. 展开更多
关键词 haze-Fog Control Digital Economy National Innovation Demonstration Zones Local Autonomy
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激光共焦显微镜对近视激光术后haze结构的研究 被引量:4
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作者 吴艳 杨丽萍 +2 位作者 薛春燕 黄振平 石尧 《眼科新进展》 CAS 北大核心 2013年第3期240-242,共3页
目的利用激光共焦显微镜观察近视激光术后的haze结构。方法选取Epi-LASIK术后发生haze患者12例(24眼)设为A组,另选择接受Epi-LASIK但无并发症发生患者10例(20眼)设为B组,行双眼激光共焦显微镜检查,观察A组患者角膜上皮层、前基质层、中... 目的利用激光共焦显微镜观察近视激光术后的haze结构。方法选取Epi-LASIK术后发生haze患者12例(24眼)设为A组,另选择接受Epi-LASIK但无并发症发生患者10例(20眼)设为B组,行双眼激光共焦显微镜检查,观察A组患者角膜上皮层、前基质层、中后基质层变化,并比较两组各层细胞密度。结果 A组角膜上皮基底膜缺如,上皮下散在斑点状瘢痕及高反光白色小点,瓣边缘见环形瘢痕,周边上皮细胞核呈高反光。角膜前基质层纤维紊乱,局部见空泡样改变及大量点状、斑片状瘢痕组织,近上皮瓣基底部大片瘢痕,其间可见细小皱褶;瘢痕间少量神经末梢走行,神经组织纤细,局部可见断裂、扭曲。中、后基质层见正常网状结构,内皮细胞"六边形"结构正常。A组角膜上皮层细胞密度为(6381.9±290.1)mm(-2),前基质层细胞密度为(482.6±53.3)mm(-2),对照组分别为(4729.1±319.2)mm(-2)和(372.4±41.2)mm(-2),两组相比差异均有统计学意义(均为P<0.05);A组中、后基质层和内皮层的细胞密度分别为(278.0±41.1)mm(-2)、(188.2±22.0)mm(-2)、(3290.1±339.2)mm(-2),对照组分别为(301.3±49.3)mm(-2)、(197.6±28.1)mm(-2)、(3102.3±322.0)mm(-2),两组相比差异均无统计学意义(均为P>0.05)。结论激光共焦显微镜可用于近视激光术后haze结构的观察评估。 展开更多
关键词 激光共焦显微镜 haze Epi—LASIK 近视
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晶片表面Haze值研究 被引量:5
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作者 张伟才 宋晶 +1 位作者 杨洪星 赵权 《半导体技术》 CAS CSCD 北大核心 2011年第9期681-683,共3页
介绍了晶片表面Haze值的定义和理论依据,通过对SSIS系统的原理分析,揭示了Haze是一种间接反映晶片表面状态的光学信号。通过对不同表面状态抛光片的光学扫描,研究了晶片表面粗糙度与Haze值的关系;通过对Si抛光片和砷化镓抛光片的扫描对... 介绍了晶片表面Haze值的定义和理论依据,通过对SSIS系统的原理分析,揭示了Haze是一种间接反映晶片表面状态的光学信号。通过对不同表面状态抛光片的光学扫描,研究了晶片表面粗糙度与Haze值的关系;通过对Si抛光片和砷化镓抛光片的扫描对比,研究了晶片本体反射系数对Haze值的影响。研究结果表明,同种材料的Haze值随着表面粗糙度的增大而增大,而不同的材料即使拥有相似的表面粗糙度,Haze值也会因本体反射系数的不同而呈现很大差异。通过对Haze扫描图的特征分析,研究了Haze值分布与晶片表面均匀性的关系,成功地利用Haze值分布将表面性状化,为化学机械抛光和湿法清洗工艺提供了一个新的反馈手段。 展开更多
关键词 haze 光散射 表面粗糙度 一致性 扫描表面检查系统
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羊膜移植对激光角膜光学切除术后haze形成的影响 被引量:2
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作者 钟一声 周颖明 +3 位作者 丁侃 叶纹 廉井财 王康孙 《上海第二医科大学学报》 CSCD 2001年第5期390-392,396,共4页
目的探讨羊膜移植对激光角膜光学切除术 (photorefractivekeratectomy ,PRK)后上皮下混浊 (haze)的影响。 方法对 18只新西兰白兔双眼行PRK ,术后一眼立即行角膜表面羊膜移植术 ,另眼作为对照。术后 4周和 8周用裂隙灯检查角膜haze形... 目的探讨羊膜移植对激光角膜光学切除术 (photorefractivekeratectomy ,PRK)后上皮下混浊 (haze)的影响。 方法对 18只新西兰白兔双眼行PRK ,术后一眼立即行角膜表面羊膜移植术 ,另眼作为对照。术后 4周和 8周用裂隙灯检查角膜haze形成情况。将兔于术后 1、4、8周处死 ,取下角膜进行常规组织切片 ,分别进行HE染色、AgNORs染色和胶原染色检查。 结果术后 4周和 8周 ,羊膜移植组haze轻于对照组。术后 1、4、8周 ,羊膜移植组切削区中央上皮层厚度明显小于对照组 (P <0 .0 5 ) ,切削区边缘上皮层厚度两组间无显著差异 (P >0 .0 5 ) ;术后 4周和 8周 ,羊膜移植组术区前基质角膜细胞数较对照组少 (P <0 .0 5 ) ,且增殖活性较对照组低 ,Ⅲ型胶原形成少。 结论羊膜移植能抑制PRK后基质角膜细胞增殖和Ⅲ型胶原形成而有效的减轻haze的形成。 展开更多
关键词 羊膜移植 激光屈光性角膜切削术 上皮下混浊 haze形成
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抛光垫使用期对300mm Si片Haze值影响研究 被引量:1
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作者 索思卓 库黎明 +5 位作者 黄军辉 葛钟 陈海滨 张国栋 盛方毓 阎志瑞 《半导体技术》 CAS CSCD 北大核心 2008年第12期1084-1087,共4页
抛光垫是化学机械抛光(CMP)过程中重要的消耗材料之一。由于抛光垫与Si片直接接触,所以抛光垫的物理特性会直接影响到所加工Si片品质的优劣。通过研究不同使用时间的抛光垫结构以及所抛光Si片表面haze值,发现抛光Si片表面haze值在抛光... 抛光垫是化学机械抛光(CMP)过程中重要的消耗材料之一。由于抛光垫与Si片直接接触,所以抛光垫的物理特性会直接影响到所加工Si片品质的优劣。通过研究不同使用时间的抛光垫结构以及所抛光Si片表面haze值,发现抛光Si片表面haze值在抛光垫使用前期逐渐减小,中期稳定缓慢升高,后期快速升高。从理论上系统地对结果进行了分析,充分证实了在CMP过程中,保持抛光垫特性的稳定对Si片表面质量具有非常重要的意义。 展开更多
关键词 精抛光 抛光垫 化学机械抛光 haze
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Analysis of the Characteristics of Typical Haze in Winter 被引量:1
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作者 张云海 王扬锋 +1 位作者 洪也 马雁军 《Meteorological and Environmental Research》 CAS 2010年第4期18-20,51,共4页
Based on meteorology and environment monitoring data in January,2008 in Liaoning central region,a typical haze weather process was analyzed.The results showed that haze was formed due to the stable weather condition i... Based on meteorology and environment monitoring data in January,2008 in Liaoning central region,a typical haze weather process was analyzed.The results showed that haze was formed due to the stable weather condition in the earth surface and upper air layer in Liaoning central region.Especially because that the weakening of atmospheric dispersion ability in the urban boundary layer that was 500 m under earth surface,caused the pollutant in the air can not disperse.Thus,it resulted in the deterioration of air quality,increase of concentration of particulate mass,and declination of visibility.And in the end,haze formed. 展开更多
关键词 haze CHARACTERISTICS Air quality Data analysis China
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LASEK术后Haze的发病机制与防治的研究进展 被引量:15
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作者 谭业双 刘磊 李新宇 《眼科新进展》 CAS 2007年第7期546-548,共3页
准分子激光角膜上皮瓣下磨镶术中保留了尚存活性的角膜上皮层,能减轻术后角膜上皮下混浊(Haze)形成。可能的原因是减少了眼表组织中白介素-1分泌和转化生长因子-β含量,降低了凋亡介导下的角膜创伤愈合。通过术中预防性使用抗代谢药物... 准分子激光角膜上皮瓣下磨镶术中保留了尚存活性的角膜上皮层,能减轻术后角膜上皮下混浊(Haze)形成。可能的原因是减少了眼表组织中白介素-1分泌和转化生长因子-β含量,降低了凋亡介导下的角膜创伤愈合。通过术中预防性使用抗代谢药物、局部应用糖皮质激素、细胞因子拮抗剂等药物以及手术治疗等方法,从而预防或减轻Haze形成,提高角膜屈光手术的稳定性和预测性。本文就近年来准分子激光角膜上皮瓣下磨镶术术后Haze的发病机制及防治措施的研究进展作一简要综述。 展开更多
关键词 准分子激光角膜上皮瓣下磨镶术 角膜上皮下混浊
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准分子激光双面式切削原位角膜磨镶术后Haze和屈光回退分析 被引量:5
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作者 袁满红 邓珍 +2 位作者 李伟力 肖启国 周珍华 《国际眼科杂志》 CAS 2007年第1期130-132,共3页
目的:评价准分子激光双面式切削原位角膜磨镶术(both-sidedLASIK,BSL)的安全性和有效性。方法:2004-12/2005-10我院进行BSL手术治疗的高度近视患者38例75眼,回顾性的对临床疗效进行分析。结果:随访9~15mo,38例患者均未出现严重并发症... 目的:评价准分子激光双面式切削原位角膜磨镶术(both-sidedLASIK,BSL)的安全性和有效性。方法:2004-12/2005-10我院进行BSL手术治疗的高度近视患者38例75眼,回顾性的对临床疗效进行分析。结果:随访9~15mo,38例患者均未出现严重并发症。术前、术后1d和9mo的平均裸眼视力分别为0.07±0.05、0.67±0.29、0.92±0.23,两两之间比较差异均有统计学意义(P<0.01)。1mo时见7眼(9%)有1级Haze形成,较常规LASIK稍多。电脑验光1d和1mo与3mo和6mo之间比较差异均有统计学意义,1mo和3mo与6mo和9mo之间比较差异均无统计学意义。结论:BSL术后能够获得较好的裸眼视力,无严重的并发症出现,屈光回退程度较轻,Haze形成较常规LASIK稍多,对角膜较薄的高度近视患者是一种较为理想、安全、有效的治疗方法。 展开更多
关键词 高度近视 准分子激光手术 角膜上皮下混浊 屈光回退
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