DCJTB掺杂的荧光型白光有机电致发光器件

本文基于为ITO/2-TNATA(20 nm)/NPB(30 nm)/BePP2:DCJTB(45 nm:X%)/Alq3(30 nm)/LiF(1 nm)/Al(100 nm)的白光器件结构(X为DCJTB的掺杂浓度(质量分数))。采用真空热蒸镀的方法,在高精度膜厚测控仪的监控下分别制备了发光层掺杂浓度为1,1.5,2.0,2.5,3.0不同器件,并对各器件性能进行了测试。实验结果表明:当DCJTB的掺杂浓度为2.0%时,平衡了器件中电子和空穴的传输能力,使载流子复合形成激子的几率增加,既使载流子的传输能力明显改善,并且有效地抑制了器件的荧光猝灭效应。在12 V电压下,可以获得发光亮度最高达到9 868cd/m2,发光效率大于7.2 cd/A,且色坐标为(0.334,0.337)的较理想白光有机发光器件。     

空穴注入层MoO_3厚度对蓝绿色磷光OLED发光特性的影响

以mCP为磷光主体材料,BGIr1为蓝绿色磷光掺杂材料,MoO3为空穴注入材料,制备5种不同厚度的MoO3蓝绿色磷光有机电致发光器件(OLED),并研究不同厚度MoO3空穴注入层对蓝绿色磷光OLED发光特性的影响。所制器件结构为ITO/MoO3(x nm)/NPB(40nm)/mCP∶BGIr1(30nm,18%)/BCP(10nm)/Alq3(20nm)/LiF(1nm)/Al(100nm),其中18%为发光层中BGIr1的掺杂量(质量分数),x为空穴注入层MoO3的厚度。研究结果表明,本实验制备器件空穴注入层MoO3的最佳厚度为20nm。当电压为13V时,MoO3厚度为20nm器件获得最大亮度为8 617cd/cm2,当电流密度为20mA/cm2时,器件获得最大发光效率为5.7cd/A。器件在488和512nm处获得两个主发射峰,发光颜色稳定,CIE坐标为(0.19,0.21)。     

新型钙镁铝合金阴极对红光OLED性能的影响研究

采用不同比例的Ca/Mg/Al合金和纯Ca/Al合金阴极分别制备结构为ITO/Mo O_3(30nm)/NPB(40nm)/TCTA(10nm)/CBP:R-4B(30nm)/TPBI(10nm)/Alq3(30nm)/Ca:Mg(X%):Al(100nm)和ITO/Mo O3(30nm)/NPB(40nm)/TCTA(10nm)/CBP:R-4B(30nm)/TPBI(10nm)/Alq3(30nm)/Ca:Al(100nm)的红光有机电致发光二极管(OLED)器件及其对应的电子型器件,研究了阴极材料对器件的影响。结果发现,Ca/Mg/Al合金阴极可以提高阴极发射电子能力。当Mg掺杂质量比为20%时,器件具有最优性能,在电压为13 V时,发光亮度为10250 cd/m2,电流密度为57.099 m A/cm2,最大电流效率为18.8426 cd/A,效率较高且滚降比较平缓。原因为载流子注入比较平衡,形成了较多的激子。     

基于中性红染料的新型红色发光材料

以具有生物染色作用的中性红染料为主结构,设计合成了两个新型中性红衍生物2-(N-邻苯二甲酰亚胺)-3-甲基-8-二甲胺吩嗪(NRDl)和N,N'-二(3-甲基-8二甲胺-2-吩嗪)-1,4,5,8-萘二酰亚胺(NRD2).实验制作了结构为ITO/NPB(43 nm)/Alq3:dopant(20 nm)/Alq3(32 nm)/Lif(1 nm)/Al(120 nm)的发光器件,在掺杂质量百分比浓度分别为1.0%、2.3%和4.1%时,NRDl的发光峰值分别为582 nm、588 nm和594 nm,在电压为12 V时,发光亮度达到5552cd·m-2,2858 cd·m-2和1985 cd·m-2.在掺杂质量百分比浓度为1.0%时,NRD2的发光峰值为558 nm,在电压为12 V时,发光亮度达到938 cd·m-2.     

PtOEP掺杂Alq3有机发光器件的能量传递

研究了高效磷光染料八乙基卟啉铂(PtOEP)掺杂于主体材料八羟基喹啉铝(Alq3)体系中PtOEP、Alq3之间的能量传输机制.分别以PtOEP掺杂和未掺杂的Alq3膜作为发光层制作有机发光器件(OLED),改变掺杂浓度,检测器件电致发光(EL)光谱的变化.经分析,在5%、10%、20%三种掺杂浓度中,10%掺杂浓度能量传递效果最好.通过对掺杂和未掺杂器件电流密度-电压、亮度-电压数据检测,计算外量子效率,在低电流密度(《7mA/cm2)驱动下掺杂器件外量子效率是未掺杂器件的5倍.     

一种新型磷光铜(I)配合物及其高效绿光有机电致发光器件

研制出了一种新型的Cu(Ⅰ)配合物[Cu(DPEphos)(PyPPN)]BF4 (CuL1L2),其中二DPEphos和PyPPN分别表示(2-二苯基膦基)苯基醚和吡啶并[1′,2′∶2,3] 吡嗪[5,6-f] 1,10-菲罗啉,并制备了结构为ITO(20)/2-TNATA (20nm)/NPB(40nm)/CBP∶8% CuL1L2(30nm)/BCP(20nm)/Alq3(20nm)/ LiF(1nm)/ Al(100nm)的掺杂式有机发光二极管(OLED).掺杂式器件在530nm处有较强的金属配合物三重态的绿光电致磷光 (ELECTROPHOSPHORESCENCE,EPL)发射,最大亮度为2388cd/m2,在电流为0.1mA时,器件的最大电流效率达到11.4cd/A,据我们所知,该OLED器件的EL性能是目前报道Cu(Ⅰ)磷光配合物的EPL器件中最高的.     

主客体掺杂和空穴阻挡对蓝色磷光OLED发光性能的影响研究

以铱配合物蓝色磷光材料Firpic作为掺杂剂,制备了基于CBP为主体的蓝色有机电致发光器件,其结构为ITO/CuPc/FIrpic:CBP(x%)/BCP/Alq3/LiF/Al,其中x%为发光层主客体掺杂浓度.分别研究了主客体掺杂浓度和空穴阻挡层BCP的厚度对器件发光性能的影响,当掺杂浓度为8%时,主客体间的能量传转移最充分,器件的启亮电压为5V,器件在20V时的亮度为7122.25cd/m2.器件电致发光(EL)光谱出现明显的红移现象,为Alq3部分参与了发光,影响了发光的色纯度,改变BCP的厚度,可以调节载流子复合区域和器件发光的色度坐标,达到改善器件发光性能的目的.     

高效稳定性有机黄光电致发光器件

主要通过红绿磷光材料R-4B和GIr1掺杂的方法,制备了黄光OLED器件,器件结构为ITO/MoO3(X)/NPB(40nm)/TCTA(10nm)/CBP:GIr1 14%:R-4B2%(30nm)/BCP(10nm)/Alq3(40nm)/LiF(1nm)/Al(100nm),TCTA和BCP分别为电子和空穴阻挡材料,同时结合TCTA和BCP对载流子的高效阻挡作用,研究了MoO3对器件效率和稳定性的影响。发现当增加MoO3的厚度为90nm时,在较大的电压范围内,器件都具有较高的效率和色坐标稳定性。在电流密度为7.13mA/cm2时,器件达到最高电流效率29.2cd/A,亮度为2081cd/m2;电流密度为151.7mA/cm2时,获得最高亮度为24430cd/m2,电流效率为16.0cd/A;器件色坐标稳定性较好,当电压为5、10、15V时,色坐标分别为(0.5020,0.4812)、(0.4862,0.4962)、(0.4786,0.5027)。器件性能的改善主要归因于载流子注入与传输的平衡以及阻挡层对发光区域的有效限定。     

基于红光染料掺杂的有机电压调制发光器件

制备了一种电压调制有机发光二极管(OLED),结构为ITO/CuPc(10nm)/NPB(70nm)/MADN(30nm)/MADN:DCM(2%(质量分数),10nm)/BCP 7nm/ALQ(30nm)/LiF(0.5nm)/Al(100nm).通过调节DCM的掺杂浓度和MADN:DCM厚度,发光颜色发生了随电压的连续变化.该器件的起亮电压在3V左右,当驱动电压为16V时最大亮度达到16652cd/m2,电流效率在8V时达到最大为5.78cd/A.     

基于N-苯基咔唑的红色有机电致发光材料

设计合成了一种N-苯基咔唑的衍生物:3-2-(3,3-二腈基亚甲基-5,5-二甲基-1-环己烯基)乙烯基-N-苯基-咔唑(PNCa-2CN).PNCa-2CN的甲醇溶液光致发光光谱和固体膜光致发光光谱峰值分别位于598nm和660nm.以PNCa-2CN作为红色发光材料掺杂在Alq3中,制备了结构为ITO/NPB/Alq3:PNCa-2CN(5%)/Alq3/Mg:Ag/Ag的具有较高发光效率的红色有机电致发光器件,器件的发光峰值为600nm,在外加20V直流电压时达到2372cd·m-2的发光亮度,100mA·cm-2和20mA·cm-2其亮度分别为323cd·m-2和64cd·m-2,器件最大流明效率达到1.3lm·W-1.     

Insertion of triangulated surfaces into a meccano tetrahedral discretization by means of mesh refinement and optimization procedures

In this paper, we present a new method for inserting several triangulated surfaces into an existing tetrahedral mesh generated by the meccano method. The result is a conformal mesh where each inserted surface is approximated by a set of faces of the final tetrahedral mesh. First, the tetrahedral mesh is refined around the inserted surfaces to capture their geometric features. Second, each immersed surface is approximated by a set of faces from the tetrahedral mesh. Third, following a novel approach, the nodes of the approximated surfaces are mapped to the corresponding immersed surface. Fourth, we untangle and smooth the mesh by optimizing a regularized shape distortion measure for tetrahedral elements in which we move all the nodes of the mesh, restricting the movement of the edge and surface nodes along the corresponding entity they belong to. The refining process allows approximating the immersed surface for any initial meccano tetrahedral mesh. Moreover, the proposed projection method avoids computational expensive geometric projections. Finally, the applied simultaneous untangling and smoothing process delivers a high‐quality mesh and ensures that the immersed surfaces are interpolated. Several examples are presented to assess the properties of the proposed method.     

Certification Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Flow calorimeter for enthalpy increment measurements on condensed gases

A flow calorimeter for enthalpy increment measurements on condensed gases is presented. A better knowledge of the properties of the liquefied natural gas is needed, and therefore a liquid loop has been designed for our flow calorimeter. The fluid loop in the calorimeter is designed in order to avoid the two-phase region, since two phases would give compositional disturbances in the measurements. The avoidance of the two-phase region is made possible by increasing the pressure of the test fluid after the measurement section, then heating the fluid at super-critical pressure past the critical point. Finally, the fluid is throttled to the low-pressure gas state at the inlet condition of the compressor that circulates the fluid. To perform the pressure increase, a new cryogenic pump has been designed. To evaluate the new equipment, measurements were taken on liquid ethane over the temperature range 146–256 K at pressure between 0.9 and 5.1 MPa.     

Refrigerators Enter a New Era of Health Preservation Frestech initiates the establishment of China's first standard for household sterilization refrigerators

On November 30, 2007, the China Association for Standardization (CAS) held a press conference at Beijing Diaoyutai State Guest House. Leaders from the China Household Electric Appliance Research Institute, the China Household Electric Appliance Association, and the China Consumers' Association attended and made speeches.……     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

A study of centrifugal cast high boron high speed steel

In the present study a high‐boron high speed steel (HSS) roll material was designed. Many expensive alloy elements have been substituted by cheap boron alloy, and high‐boron high speed steel roll has been manufactured by centrifugal casting method. The microstructures, mechanical properties and wear resistance of centrifugal casting high‐boron high speed steel roll have been investigated by optical microscopy (OM), scanning electron microscopy (SEM), and X‐ray diffraction (XRD) analysis, hardness test, impact test and wear test. The results indicated that the solidification microstructures of high‐boron high speed steel roll consisted of M₂(B,C), (W,Mo)₂(B,C), M₃(B,C), M₂₃(B,C)₆ type borocarbides and martensite, a small amount of retained austenite. Borocarbides were continuously distributed over the grain boundary. After quenching from 1050 °C, local broken network appeared in partial borocarbides, and fine secondary borocarbide precipitated from the matrix. After tempering from 525 °C, the amount of precipitated borocarbide increased significantly. After heat treatment, the hardness of high‐boron high speed steel roll excelled 60 HRC, and its impact toughness excelled 8.0 J/cm². The single groove steel rolling amount of high‐boron high speed steel rolls increases by 500% than that of bainite cast iron roll, when the rolls are used in K₁ mill housing of bar mill.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.