Centimeter-sized Cs_(3)Cu_(2)I_(5)single crystals grown by oleic acid assisted inverse temperature crystallization strategy and their films for high-quality X-ray imaging

Low-dimensional halide perovskites have become the most promising candidates for X-ray imaging,yet the issues of the poor chemical stability of hybrid halide perovskite,the high poisonousness of lead halides and the relatively low detectivity of the lead-free halide perovskites which seriously restrain its commercialization.Here,we developed a solution inverse temperature crystal growth(ITCG)method to bring-up high quality Cs_(3)Cu_(2)I_(5)crystals with large size of centimeter order,in which the oleic acid(OA)is introduced as an antioxidative ligand to inhibit the oxidation of cuprous ions effieiently,as well as to decelerate the crystallization rate remarkalby.Based on these fine crystals,the vapor deposition technique is empolyed to prepare high quality Cs_(3)Cu_(2)I_(5)films for efficient X-ray imaging.Smooth surface morphology,high light yields and short decay time endow the Cs_(3)Cu_(2)I_(5)films with strong radioluminescence,high resolution(12 lp/mm),low detection limits(53 nGyair/s)and desirable stability.Subsequently,the Cs_(3)Cu_(2)I_(5)films have been applied to the practical radiography which exhibit superior X-ray imaging performance.Our work provides a paradigm to fabricate nonpoisonous and chemically stable inorganic halide perovskite for X-ray imaging.

Performance of Large Area Thin-Film CdTe Detector in Diagnostic X-Ray Imaging

Significant advancement in thin-film cadmium telluride (CdTe) deposition techniques in recent years has made this material attractive for the development of low-cost large area detector. Here we evaluate the intrinsic performance of the detector for a range of energies relevant to diagnostic imaging applications, such as fluoroscopy. The input x-ray spectra for a set of tube potentials ranging from 70 to 140 kVp were computed with the tungsten anode spectral model using interpolating polynomials (TASMIP) based on the measured output of our diagnostic x-ray simulator. Frequency-dependent detector performance analysis was conducted through Monte Carlo simulations of energy deposition within the detector. Intrinsic modulation transfer functions (MTF), noise power spectra (NPS), and detective quantum efficiencies (DQE) were computed for a set of CdTe detectors of varying thickness, from 100 to 1000 μm. MTF behavior at higher frequencies was affected by thickness and input energy, NPS increased with film thickness and energy, and the resultant DQE(f) decreased with increasing the input energy, but increased with the thickness of the detector. We found that the optimal thickness of CdTe under diagnostic x-ray beam is in the range of 300 to 600 μm. Physical properties of CdTe, such as the high atomic number and density, used in direct detection configuration, together with the recently established thin-film manufacturing techniques makes this technology a promising photoconductor for large area diagnostic flat panel imaging.

Hydrophobic long-chain two-dimensional perovskite scintillators for underwater X-ray imaging

The underwater X-ray imaging technology development is significant to subaqueous target reconnaissance/detection/identification, subfluvial archaeology,submerged resource exploration, etc. As the core of X-ray imaging detection, the scintillator has been plagued by inherent moisture absorption and decomposition, and strict requirements for seamless packaging and waterproofing.Here, we designed a manganese-doped two-dimensional(2D) perovskite scintillator modified by hydrophobic longchain organic amine through the combination of component and doping engineering. The modified perovskites show high water repellency that can be used as an underwater X-ray scintillator. X-ray images of aquatic organisms or other objects with a high spatial resolution of10 lp·mm^(-1) at a big view field(32 mm × 32 mm) were obtained by scintillation screen. This hydrophobic perovskite scintillator based on molecular design is of great promise in underwater X-ray nondestructive testing technology development.

Study progression in application of process analytical technologies on film coating

Film coating is an important unit operation to produce solid dosage forms,thereby,the monitoring of this process is helpful to find problems in time and improve the quality of coated products.Traditional methods adopted to monitor this process include measurement of coating weight gain,performance of disintegration and dissolution test,etc.However,not only do these methods cause destruction to the samples,but also consume time and energy.There have recently emerged the applications of process analytical technologies(PAT)on film coating,especially some novel spectroscopic and imaging technologies,which have the potential to real-time track the progress in film coating and optimize production efficiency.This article gives an overview on the application of such technologies for film coating,with the goal to provide a reference for the further researches.

Rapid digitalization and panoramic evaluation of weld X-ray film

The computer evaluation of weld X-ray film is an attractive technique for weld seam NDT （ nondestructive testing）. To achieve this target, digitalization of film is the first step and automatic defect identification is another key technique. In this paper, a weld X-ray film digitalizing system has been established with linear array CCD and highlight LED light source. Its space resolution can reach 0. 04 mm/pixel and scanning speed can reach 100 mm/s for an industrial film. The transfer function curves of the system have been measured and the results indicate that its image gray resolution can reach 88 G/D at 4. 5D, and its dynamic range can be wider than 2. OD. In order to facilitate the evaluation of large welded structure, a panoramic evaluation algorithm is developed also. The algorithm includes image matching, image fusion and panoramic evaluation of the long linked film image.

汽车用硫系玻璃元件红外双波段增透膜的研制

基于硫系玻璃IRG206(As40Se60)基底,研制了3.7~4.8μm及7.5~9.5μm双波段增透膜,可用于汽车红外夜视成像系统。采用电子束和电阻蒸发离子辅助沉积技术,结合化学键分析选取连接层材料,提高基底与膜层之间的结合力;利用离子辅助应力调控技术,优化膜层应力,实现膜层应力的匹配,解决硫系玻璃表面脱膜问题。测试结果表明,该膜层在3.7~4.8μm波段平均透过率为98.31%,在7.5~9.5μm波段平均透过率为97.43%,通过了牢固度、盐雾、高低温、摩擦等环境测试,能够满足汽车红外夜视成像系统的使用要求。

Orientation and mobility control of 4HCB organic film for flexible X-ray detectors with high performance

In comparison to inorganic counterparts,organic semiconducting(OSC)crystalline films are promising for building large-area and flexible ionizing radiation detectors for X-ray imaging or dosimetry due to their tissue equivalence,simple processing and large-scale production accessibility.Fabrication processes,how-ever,hinder the ability to generate aligned and large-area films with high carrier mobility.In this work,the space-confined melt process is used to produce highly orientated 4HCB(4-hydroxycyanobenzene)OSC films with a large area of 15×18 mm^(2).The out-of-plane direction of the 4HCB film is<001>,and the benzene rings are found to be extensively overlapped inside the in-plane direction,according to the XRD patterns.The film exhibits a high resistivity up to 1012cm,and high hole mobility of 10.62 cm^(2)V^(−1)s^(−1).Furthermore,the 4HCB(80μm-thick film)based X-ray detectors can achieve a sensitivity of 93μC Gy air^(−1) cm^(−2)and on/offratio of 157.The device also shows steady flexibility,with no degradation in detecting function after 100 cycles of bending.Finally,the proposed 4HCB film detectors demonstrated a high-resolution X-ray imaging capability.The imaging of several materials with sharp edges(copper and polytetrafluoroethylene)has been obtained.This work has developed a fast but efficient approach for producing large-area,highly oriented OSC films for high-performance X-ray detectors.

“一体化全景成像人工智能平台”的临床应用价值分析

目的探讨“一体化全景成像人工智能平台”中的全长位片拼接软件结合普通DR机在膝关节置换围手术期的应用价值。方法选取2021年12月至2022年12月于江西中医药大学附属医院关节骨科进行TKA或UKA手术的患者30例,采集所有患者术前、术后双下肢全长负重位片,观察组利用本平台软件结合普通DR机进行下肢全长位片的拼接,对照组利用院内全自动拼接设备及软件进行下肢全长位片的拼接,并对拼接好的双下肢全长负重位片胫股角进行测量,后将同一患者观察组所测胫股角数值与对照组进行对比,分析并记录胫股角测量的准确率,然后将两者的成片从图像质量、接缝精度、连接图像对比度等多个方面进行详细比较,以确保图像的准确性和一致性,将两者的成片分为A类图像、B类图像、C类图像。结果使用本平台软件进行术前、术后图像拼接的30例患者其胫股角与院内全自动拼接设备相比较,差异无统计学意义(P>0.05),且其胫股角测量准确率为100%。图像A类图片率为95%,B类图片率为5%,无C类图片。经证实,本平台软件拼接的双下肢全长负重位片质量均优良,其图像清晰度优异,能准确地反映下肢力线,其图像质量差异与院内全自动拼接设备及其软件所拼接图像对比,差异无统计学意义(P>0.05)。结论本平台软件所拼接的双下肢全长负重位片能够精准测量下肢力线及胫股角,对于无自动拼接设备的医院进行膝关节置换术前方案制定、术中指导定位和截骨、术后对患者疗效进行评估等都有着重要的应用价值,确实值得临床推广及应用。

感光干膜相关技术研究进展

感光干膜又称光致抗蚀干膜,是一种固态负性光刻胶,作为生产印制电路板(printed circuit board,PCB)的重要原材料之一,市场规模巨大。随着电子产品精密和微型化需求的日益增长,传统的PCB生产技术,图形转移技术无法满足生产需求;激光直接成像(laser direct imaging,LDI)技术具有高精度特点,被广泛应用于感光干膜生产中。从感光干膜的性能和特征、感光干膜行业的技术壁垒及感光感膜的发展现状和应用领域等方面综述了感光干膜相关技术的研究进展,为相关行业工作者提供理论参考。

A Review of Engine Fuel Injection Studies Using Synchrotron Radiation X-ray Imaging

Fuel spray characteristics directly determine the formation pattern and quality of the fuel/air mixture in an engine,and thus affect the combustion process.For this reason,the improvement and optimization of fuel injection systems is crucial to the development of engine technologies.The fuel jet breakup and atomization process is a complex liquid-gas two-phase turbulent flow system that has not yet been fully elucidated.Owing to the limitations of standard optical measurement techniques,the spray breakup mechanism and its interaction with the nozzle internal flow are still unclear.However,in recent years synchrotron radiation(SR)X-ray imaging technologies have been widely applied in engine fuel injection studies because of the higher energy and brilliance of third-generation SR light sources.This review provides a brief introduction to the development of SR technology and compares the critical parameters of the primary third-generation SR light sources available worldwide.The basic principles and applications of various X-ray imaging technologies with regard to nozzle internal structure measurements,visualization of in-nozzle flow characteristics and quantitative analyses of near-field spray transient dynamics are examined in detail.

影视后期抠像技术分析

随着影视行业的不断发展,后期制作技术的地位越来越重要。其中,抠像技术是一种至关重要的图像处理技术。通过抠像处理,可以将图像或视频中某个部分进行分离,从而与其他元素进行组合、替换或者特效处理。随着科技的发展,影视后期抠像技术日益成熟,从手动抠像发展到如今的自动化智能抠像。基于此,介绍影视后期抠像技术的原理、实现目标及关键技术,并探讨其在影视制作中的应用。

基于物联网技术的覆冰舞动综合监测装置研究

针对覆冰舞动监测设备使用过程中出现的难题,研制了一种基于物联网技术的覆冰舞动综合监测装置,采用在线取电方式,有效解决了覆冰期间监测系统供能不足的难题。为防止覆冰期镜头被冰覆盖,采用有机薄膜加热技术对镜头加热。采用双目摄像头采集导线正常状态与覆冰舞动状态照片,通过覆冰舞动图像识别算法,精确计算出覆冰厚度和舞动强度。为保证无人或偏远地区的监测数据能够及时、稳定地传输,监测数据采用4G信号和北斗短报文双通信模块进行传输,设备监测数据经过安全接入平台与物联网管理平台连接,实现输电线路覆冰舞动现象的实时监测预警。

电影2D/3D转换技术概述

3D电影能够比传统电影带来更好的视觉体验,并在近年来得到了快速的发展,但是片源不足成为制约这一产业兴起的主要瓶颈.在当前电影产业朝3D化方向蓬勃发展的趋势下,将2D电影转为3D电影是解决此问题的有效途径.文中对电影2D?3D转换技术进行了总结,按摄像机和场景相对运动的4种不同类型,介绍了其中几种基本的转换方法,并在此基础上进一步介绍了几种重要的高级转换方法,最后提出了今后的研究方向.

数字技术语境中电影的真实性美学——从巴赞摄影影像本体论谈起

随着数字虚拟成像技术在电影中的广泛运用,巴赞的电影美学理论受到了诸多质疑。数字化对传统电影的巨大冲击,使人们不得不重新思考"真实"在电影中的地位。实际上,当我们辩证地解读巴赞影像本体论,会发现他强调的是"真实观"而并非"真实的手段",这种"真实观"包含画面与心理的真实。因此,数字电影实际上是通过制造"以假乱真"的画面和符合观众的心理期待、产生心灵的意义来还原真实的本性。在延续传统电影真实美学的基础上,数字电影更是通过呈现实景所难以获得的场景效果、创造全新的电影语言风格、强化时空处理带来的视觉逼真、虚拟角色制造出英雄情结,来推进电影的真实性表达。而从当前的形势看来,唯有对画面真实与心理真实的共同把握,才能实现技术与艺术的完美结合,让中国的数字电影展现独特的魅力。

Gd_2O_3:Eu^(3+)X射线溶胶-凝胶发光薄膜的制备与表征

With the pretreatment of pyrolysis, the uniform, smooth, dense and crack free Gd2O3∶Eu3+ films were obtained by sol-gel process without shielding atmosphere. Atomic force microscopy （AFM）, X-ray diffraction （XRD）, Ellipsometry, transmission, photoluminescence and X-ray excited emission were applied to study to the surface morphology, structure, thickness and optical properties of the films. The results show that the films are made up of grains with cubic structure in average size about 22 nm. With 21 times reproducible spin coating and pyrolysis treatment, the thickness of the film could reach to 792 nm and the transmittance of the film in visible region is above 90%. Two peaks at 223 and 250 nm are found in excitation spectra, which correspond to host lattice （HL） excitation and charge transfer （CT） excitation, respectively. Meanwhile, the main peak relates to HL excitation which is contrary to that of Gd2O3∶Eu3+ powder. This phenomenon will be beneficial to radioluminescence. The emission spectra show that the main peak located at 611 nm could be excited either by UV or X-ray, which correspond to （（）7F2→（）5D0） transition in Eu3+ ions. The luminescence intensity at 10 ms is only 10-4 time of that at 10 μs, which means that the afterglow in Gd2O3∶Eu3+ films is insignificant for X-ray imaging.

CR技术与胶片射线照相技术检测能力的对比

对CR技术和胶片射线照相技术的记录介质结构、对比灵敏度以及缺陷检测能力进行了对比。结果表明,CR技术在对比灵敏度和缺陷检出能力方面,与胶片射线照相技术基本达到同等技术水平;CR技术具有比胶片射线照相技术宽容度大、曝光量小的优点,可大大提高工作效率,但CR技术对散射线较为敏感,在使用过程中应注意散射线的防护。

CT三维重建影像技术在胫骨平台骨折分型中的应用价值

目的:将CT三维重建技术用于胫骨平台骨折诊断中,分析其对胫骨平台骨折分型的应用价值。方法:对53例胫骨平台骨折患者临床资料回顾性分析,所有患者均接受X线片及CT三维重建影像技术进行诊断检查,并将诊断结果与临床手术分型标准进行比较,评价两种诊断方法的临床应用价值。结果:与手术分型标准相比,X线诊断胫骨平台骨折分型准确率为84.91%,CT三维重建影像技术分型准确率为98.11%,高于X线片诊断准确率(P<0.05)。结论:CT三维重建影像技术用于胫骨平台骨折分型诊断中准确率较高,具有较好应用价值,可为临床制定治疗方案提供有力依据,值得临床应用。

口腔放射中报废成像板的改造利用

目前应用CR(computed radiography)技术进行口腔颌面医学影像检查被广泛应用。作为CR技术的核心组件-成像板(image plate,IP)承载着重要作用。其易磨损及划伤势必会影响成像效果,也缩短了使用寿命。笔者在操作中利用一些常用的工具对IP加以改造,使其能达到理想的使用寿命,而且摄取的影像更加清晰。

成像技术的回顾与展望

阐述了成像技术发展的3个阶段:机械电子化、自动化、数字成像阶段.具体包括胶片式向磁记录式的转变,胶片式与数字式的兼容,数字式的空间、辐射、光谱和时间分辨率成像的前沿技术.提出由部件到系统的成像自动处理控制理论,并阐述了未来成像技术的发展趋势.

试论数字技术对中国武侠电影的影响

20世纪90年代伴随着数字技术的发展与普及,电影工业产生了一次全新的变革。聚焦近20年来中国武侠电影的发展,数字技术的介入不仅改变了武侠电影原有的生产工艺、运作机制,影响了受众的观影习惯,还对传统武侠电影的创作理念、审美取向和本质属性提出了重新思考的要求。通过对两部不同时期的经典武侠片《少林寺》(1982)和《卧虎藏龙》(2000)的分析、比较,探讨了在数字技术语境下中国武侠电影所发生的变化、存在的困惑和面对的未来。