Electron Injection Enhancement by Diamond-Like Carbon Film in Polymer Electroluminescence Devices

A diamond-like carbon （DLC） film is deposited as an electron injection layer between the polymer light-emitting layer（MEH-PPV） and aluminum （Al） cathode electrode in polymer electroluminescence devices （PLEDs） using a radio frequency plasma deposition system. The source material of the DLC is n-butylamine. The devices consist of indium tin oxide （ITO）/MEH-PPV/DLC/Al. Electron injection properties are investigated through I-V characteristics,and the mechanism of electron injection enhancement due to a thin DLC layer has been studied. It is found that： （1） a DLC layer thinner than 1.0nm leads to a higher turn-on voltage and decreased electroluminescent （EL） efficiency; （2） a 5.0nm DLC layer significantly enhances the electron injection and results in the lowest turn-on voltage and the highest EL efficiency; （3） DLC layer that exceeds 5.0nm results in poor device performance;and（4） EL emission can hardly be detected when the layer exceeds 10.0nm. The properties of ITO/MEH-PPV/DLC/Al and ITO/MEH-PPV/LiF/Al are investigated comparatively.

A New Heat Transfer Model for Multi-Gradient Drilling with Hollow Sphere Injection

Multi-gradient drilling is a new offshore drilling method.The accurate calculation of the related wellbore temperature is of great significance for the prediction of the gas hydrate formation area and the precise control of the wellbore pressure.In this study,a new heat transfer model is proposed by which the variable mass flow is properly taken into account.Using this model,the effects of the main factors influencing the wellbore temperature are analyzed.The results indicate that at the position where the separation injection device is installed,the temperature increase of the fluid in the drill pipe is mitigated due to the inflow/outflow of hollow spheres,and the temperature drop of the fluid in the annulus also decreases.In addition,a lower separation efficiency of the device,a shallower installation depth and a smaller circulating displacement tend to increase the temperature near the bottom of the annulus,thereby helping to reduce the hydrate generation area and playing a positive role in the prevention and control of hydrates in deepwater drilling.

Air-Stable Ultrabright Inverted Organic Light-Emitting Devices with Metal Ion-Chelated Polymer Injection Layer

Here,this work presents an air-stable ultrabright inverted organic lightemitting device(OLED)by using zinc ionchelated polyethylenimine(PEI)as electron injection layer.The zinc chelation is demonstrated to increase the conductivity of the PEI by three orders of magnitude and passivate the polar amine groups.With these physicochemical properties,the inverted OLED shows a record-high external quantum efficiency of 10.0% at a high brightness of 45,610 cd m^(-2) and can deliver a maximum brightness of 121,865 cd m^(-2).Besides,the inverted OLED is also demonstrated to possess an excellent air stability(humidity,35%)with a half-brightness operating time of 541 h@1000 cd m^(-2) without any protection nor encapsulation.

Bright hybrid white light-emitting quantum dot device with direct charge injection into quantum dot

A bright white quantum dot light-emitting device （white-QLED） with 4-[4-（1-phenyl-lH-benzo[d]imidazol-2- yl）phenyl]-2- [3-（tri-phenylen-2-yl）phen-3-yl]quinazoline deposited on a thin film of mixed green/red-QDs as a bilayer emitter is fabricated. The optimized white-QLED exhibits a turn-on voltage of 3.2 V and a maximum brightness of 3660 cd/m2 @8 V with the Commission Internationale de l＇Eclairage （CIE） chromaticity in the region of white light. The ultra-thin layer of QDs is proved to be critical for the white light generation in the devices. Excitation mechanism in the white-QLEDs is investigated by the detailed analyses of electroluminescence （EL） spectral and the fluorescence lifetime of QDs. The results show that charge injection is a dominant mechanism of excitation in the white-QLED.

Improvement of electron injection of organic light-emitting devices by inserting a thin aluminum layer into cesium carbonate injection layer

We investigate the electron injection effect of inserting a thin aluminum（Al） layer into cesium carbonate（Cs2CO3）injection layer. Two groups of organic light-emitting devices（OLEDs） are fabricated. For the first group of devices based on Alq3, we insert a thin Al layer of different thickness into Cs2CO3 injection layer, and the device＇s maximum current efficiency of 6.5 cd/A is obtained when the thickness of the thin Al layer is 0.4 nm. However, when the thickness of Al layer is 0.8 nm, the capacity of electron injection is the strongest. To validate the universality of this approach, then we fabricate another group of devices based on another blue emitting material. The maximum current efficiency of the device without and with a thin Al layer is 4.51 cd/A and 4.84 cd/A, respectively. Inserting a thin Al layer of an appropriate thickness into Cs2CO3 layer can result in the reduction of electron injection barrier, enhancement of the electron injection, and improvement of the performance of OLEDs. This can be attributed to the mechanism that thermally evaporated Cs2CO3 decomposes into cesium oxides, the thin Al layer reacts with cesium oxides to form Al–O–Cs complex, and the amount of the Al–O–Cs complex can be controlled by adjusting the thickness of the thin Al layer.

Lowering the driving voltage and improving the luminance of blue fluorescent organic light-emitting devices by thermal annealing a hole injection layer of pentacene

We chose pentacene as a hole injection layer（HIL） to fabricate the high performance blue fluorescent organic lightemitting devices（OLEDs）. We found that the carrier mobility of the pentacene thin films could be efficiently improved after a critical annealing at temperature 120℃. Then we performed the tests of scanning electron microscopy, atomic force microscopy, and Kelvin probe to explore the effect of annealing on the pentacene films. The pentacene film exhibited a more crystalline form with better continuities and smoothness after annealing. The optimal device with 120℃ annealed pentacene film and n-doped electron transport layer（ETL） presents a low turn-on voltage of 2.6 V and a highest luminance of 134800 cd/m^2 at 12 V, which are reduced by 26% and improved by 50% compared with those of the control device.

Polymer light-emitting devices using poly(ethylene oxide) as an electron injecting layer

The performance of polymer light emitting devices(PLEDs)based on polyvinyl carbazole(PVK)is improved by introducing a nanoscale interfacial thin layer,made of poly(ethylene oxide)(PEO),between the calcium cathode and the PVK emissive layer.It is believed that the PEO layer plays a key role in enhancing the device performance.In comparison to the device with Ca/Al as the cathode,the performance of the PLED with PEO/Ca/Al cathode,including the driving voltage,luminance efficiency is significantly improved.These improvements are attributed to the introduction of a thin layer of PEO that can lower the interfacial barrier and facilitate electron injection.

Efficacy and Safety in Intramuscular Injection Techniques Using Ultrasonographic Data

Delivered by intramuscular (IM) injections, Long Acting Injections (LAI), offering comparatively long term medicinal effects from several weeks to several months, are gaining much attention. The aim of this article was to indicate a safe and effective IM injection technique based on evidenced data derived from ultrasonographic data. Accurate anatomical knowledge is necessary in order to administer IM injections. It is possible to gain an adequate understanding of injection site anatomical structures by using ultrasound diagnostic devices. In particular, ultrasonography offers real-time diagnostic data allowing for observation of injection site, subcutaneous tissues, fat layers, muscle membrane, muscles and bones. To deliver the drug accurately into the muscle is essential, to achieve maximum drug efficacy and prevent injection site reactions. Therefore, when administering IM injections to the buttocks area, a suitable injection needle between 23G 25 mm to 21G or 22G 38 mm must be chosen depending on physique and drug characteristics. Needles determined as safe and effective through ultrasonographic evidence are needed such as in the case of a deltoid injection site, in which a 23G 25 mm injection needle is used in the absence of notable obesity. Not only the needle type is essential, but also the IM procedure itself. It is important to stretch the skin, inserting the needle at 90 degree angle to ensure depth of needle insertion to the muscle. Until new con-firmed evidence becomes available, it is necessary to increase the understanding of injection site selection methods, needle insertion depth, needle angle, and established IM injection techniques. The application of ultrasound devices in the development of next-generation techniques for IM injection is promising. Importantly, these techniques provide critical information from a risk management perspective.

Influences of Injection Barrier and Mobility on Recombination Rate and Zone in OLEDs

The luminous efficiency of organic light-emitting devices depends on the recombination probability of electrons injected at the cathode and holes at the anode. A theoretical model to calculate the distribution of current densities and the recombination rate in organic single layer devices is presented taking into account the charge injection process at each electrode, charge transport and recombination in organic layer. The calculated results indicate that efficient single-layer devices are possible by adjusting the barrier heights at two electrodes and the carrier mobilities. Lowering the barrier heights can improve the electroluminescent(EL) efficiency pronouncedly in many cases, and efficient devices are still possible using an ohmic contact to inject the low mobility carrier, and a contact limited contact to inject the high mobility carrier. All in all, high EL efficiency needs to consider sufficient recombination, enough injected carriers and well transport.

A SINGLE-CAVITY MULTIPLE-DEVICE HARMONIC OSCILLATOR AT W-BAND

The equivalent circuit of single-cavity multiple-device fundamentaloscillator(SCMDFO)and that of single-device harmonic oscillator(SDHO)proposed byK.Kurokawa and K.Solbach,respectively,are extended and applied to a single-cavitymultiple-device harmonic oscillator(SCMDHO).By means of describing the functions ofnonlinearity of Gunn diodes,the performances of the SCMDHO are analyzed.It is foundthat the voltage amplitudes are similar to those of SDHO,and the ratio of maximum pow-er of harmonic to that of fundamental is identical to that in SDHO when the devices havesame parameters.The harmonic injection locking behavior is also investigated.The injec-tion locking range is greater than that of SDHO if locking gain remains constant.A2-Gunn diode harmonic oscillator was designed.It delivers 30mW output power at103GHz.The mechanical tuning range is 4.15GHz when the output power remains morethan 10mW.The desired operation mode is stable.

大尺度自航模气层减阻试验研究

[目的]旨在研究气流量、航行倾角对船底凹槽内气层保持和节能效果的影响。[方法]以一艘肥大型散货船的较大尺度缩比模型为研究对象,通过设计气层减阻自航模系统和船底凹槽方案,开展开阔水域条件下自航模气层减阻试验,研究模型正浮状态下喷气减阻效果,以及模型一定纵倾角状态下对航速和轴功率的影响。[结果]结果表明:在主机转速一定时,喷气可以明显提高自航模的航速,停止喷气后,船底凹槽内的气体仍能维持较长时间;船体艉倾角为0°~0.25°时的气层减阻效果较好,较大艉倾角时气体从自航模艏部两侧溢出,气层无法对船底实现有效覆盖,减阻效果不佳。[结论]研究结果可对气层减阻技术在肥大型船舶上的工程应用提供一定参考。

工字钢新型快速套接装置的研制

为适应不同中小跨径桥梁的抢修需求,提出研制工字钢新型套接装置实现工字钢的快速接长,明确了套接装置总体结构和承载要求,自此基础上设计了套接装置的三种连接方式,基于足尺模型试验探究快速套接装置连接工字钢的最优方式。研究结果表明:相较于注胶连接、灌浆连接,套接装置采用“预留开槽+现场槽孔塞焊”的连接方式,既可以保证其具有不低于工字钢的承载力,又能实现不同跨径应急钢桥的快速连接。

直注式秸秆捡拾粉碎深埋机设计与试验

为提升秸秆深埋质量,针对秸秆深埋过程中秸秆捡拾效果差、输送方式单一、输送效率低、深埋率低等问题,提出一种直注式秸秆深埋还田方法,设计了直注式秸秆捡拾粉碎深埋机,阐述了整机结构和工作原理。对关键部件进行了设计分析,设计了无护圈式捡拾装置,分析了捡拾装置各个运动阶段与弹齿的运动轨迹,确定了4个运动阶段所对应的相位角;设计了以运秸螺旋输送器和运秸叶片为主的机械输送装置、以抛秸风叶和运秸导管为主的气力输送装置。对秸秆输送量进行分析,明确了运秸螺旋输送器结构参数,得出了运秸螺旋输送器最低转速;对运秸叶片和抛秸风叶进行了动力学分析,确定了运秸叶片和抛秸风叶结构,明晰了影响秸秆输送效果的关键因素为机具前进速度、运秸螺旋输送器转速、抛秸风叶转速、运秸叶片倾角和抛秸风叶倾角,并确定了影响因素范围。仿真试验结果表明,机具前进速度和运秸螺旋输送器转速存在交互作用,最佳作业参数:机具前进速度为3 km/h、运秸螺旋输送器转速为1200 r/min和抛秸风叶转速为1600 r/min。田间试验结果表明,平均秸秆捡拾率和平均深埋率分别为91.02%,90.03%;运秸导管出口处风速和作业扭矩分别为1.78~26.83 m/s、61.55~214.78 N·m,各工作部件运行稳定,满足秸秆深埋还田作业要求,为秸秆深埋还田机研发和改进提供了依据。

基于双频信号注入法的船舶交流电网绝缘监测装置应用探析

为了解决船舶交流电网绝缘故障实时在线监测定位问题,提出了一种基于双频信号注入法的船舶交流电网绝缘监测装置设计方案。对双频信号注入法的工作原理进行研究,系统以STM32F103ZE芯片为控制核心,运用基2时间抽取1024点FFT实现注入低频信号的提取。明确了注入信号的频率选取原则,试验分析确定注入信号频率为15 Hz和5 Hz。经过实际运行测试与结果分析,基于双频信号注入法的船舶交流电网绝缘监测装置最大误差率不超过2%,完全满足对地绝缘电阻测量精度±5%的设计要求。试验结果验证了船舶交流电网绝缘监测装置的可靠性和有效性,所提出设计方案大大降低船员工作强度,提高了舰船电力系统的供电连续性和安全性。

井下油水分离装置现状与展望

油田进入开发中后期,采出液含水率急剧上升,如何降低含水率并提高采收率是开发后期需要解决的首要问题。井下油水分离技术利用水力旋流技术、重力分离技术或其他油水分离工艺实现在井下对采出液进行预分离,从而采出较低含水率的油水混合液,此项技术对于高含水油田具有很大应用前景。通过对井下油水分离装置的研究现状进行简要分析与总结,并指出目前井下油水分离装置存在的问题与挑战,同时做出展望,为其发展提供一定的参考。

纳米CMOS器件中热载流子产生缺陷局域分布的表征

本文针对纳米小尺寸CMOS器件,提出了一种根据表面势模型表征热载流子产生电荷陷阱和界面态局域分布的方法。热载流子注入(Hot Carrier Injectione,HCI)应力会在栅氧化层和Si/SiO_(2)界面中产生电荷陷阱和界面态,随着应力时间递增,这些缺陷的增多引起阈值电压等器件参数的漂移,在漏致势垒降低(Drain Induced Barrier Lowering,DIBL)效应下,可以选取表面势最大值处的阈值电压偏移量来表征沟道相应位置处HCI致电荷陷阱和界面态。研究发现,通过测量施加HCI应力前后器件阈值电压偏移量随源/漏极电压的分布,结合表面势模型计算出源/漏极电压随沟道表面势峰值的分布,可以得到HCI致电荷陷阱和界面态沿沟道的局域分布。利用此方法,精确地表征了在32 nm CMOS器件中HCI应力引起的电荷陷阱和界面态沿沟道的分布,并进一步分析了HCI效应的产生机理。

盐穴压缩空气储能库注采井筒体系优化设计

盐穴因其密封与稳定特性成为压缩空气储能库(以下简称储能库)首选,储能库可以实现大规模的清洁储能,能实现电力供需的“削峰填谷”,是实现“双碳”目标的重要方向之一。井口装置、注采管和封隔器组成的井筒体系是储能库与地面设备的连接通道,然而受气体注采流量的限制和冲蚀作用的影响,现阶段的小通径井筒严重限制了压缩空气储能电站的装机规模。为优化储能库注采井筒体系,对大通径井口装置、耐腐蚀套管和大尺寸封隔器的设计与加工中存在的主要问题进行了分析,并结合工程实际提出了解决措施和合理化建议。研究结果表明:(1)井口装置设计需考虑到每层套管头座挂芯轴悬挂器台阶的承载强度,需要校核及验证悬挂器最小壁厚处的抗外挤强度、承受井下反压时顶丝的抗剪切强度等参数;(2)套管选材应充分考虑制造工艺及经济成本在盐穴压缩空气储能工况中的适用性,建议在易发生冲蚀处使用耐蚀合金纯管材,其余部位优选具有性价比的耐腐蚀套管;(3)大尺寸封隔器建议整体采用芯轴设计,胶筒选用氢化丁腈橡胶或四丙氟橡胶等材质,卡瓦建议采用笼式桶状。结论认为,提出的注采井筒体系设计优化措施,能够为该类型储能项目的大尺寸井筒注采体系设计与优化提供方法和思路。

单环注水试验新装置的研制与应用

针对传统单环试坑注水试验装置在注水流量观测时存在误差大、效率低等问题,研制了单环注水试验新装置。该装置主要由马氏瓶、数字差压计、注水钢环等组成,采用数字差压计对马氏瓶内外压强差进行测量,再将测得的气体压强差换算为马氏瓶内水柱高度值,从而可计算出每个观测时间段内由马氏瓶注入钢环内的水量,性能测试结果显示注水量观测相对误差小于3.8%。采用单环注水试验新装置测试兰州新区某工程建设场地填土层的渗透系数,试验结果表明:试验场地填土渗透系数为1.03×10^(-4)cm/min~2.09×10^(-4)cm/min,属中等透水地层;入渗水在竖向与水平向的影响范围差异不大,浸润范围内土体的含水率消散较快。该单环注水试验新装置能够研究原位条件下的土体渗透及水分迁移规律,结构简单、操作方便、测试精度高。

一种便携式骨髓腔内注射装置的设计

目的:为实现可视化精准穿刺,设计一种便携式骨髓腔内注射装置。方法:该装置主要由握持壳体、显示屏、穿刺针、控制器及电源组成。其中,握持壳体呈L形,采用新型高性能热塑性树脂制作,且手柄部位设有聚乙烯-醋酸乙烯酯防滑胶带;显示屏采用透明纳米微晶玻璃制作;穿刺针由内针和外针组成,采用奥氏体不锈钢材料制作;电源选用磷酸铁锂电池。结果:该装置不仅可实现安全、快速穿刺,而且具有实时监测穿刺压力及深度的功能。结论:该装置能够实现可视化精准操作,具有操作简便、携带方便、安全耐用等优势,有利于提高救治成功率。

一种便携式气体自动进样装置的研制及性能验证

根据JJG 700-2016《气相色谱仪检定规程》对火焰离子化检测器(FID)和热导检测器(TCD)的检校要求,设计并研制一种便携式气体自动进样装置。该装置可实施气体的连续自动进样,进样体积范围覆盖(0.1~5.0)mL,且性能验证实验测得的连续7次峰面积重复性(RSD)为0.9%。同时,装置自身的稳定性和操作的便利性,能有效提高气相色谱仪的计量质量和效率。