Synthesis and Fluorescent Properties of New Binuclear Europiumβ-Diketone Chelates Eu_mY_(1-m)(TTA)_3phen as Red Electroluminescent Materials

Organicthinfilmelectr0luminescentdisplay(OTFELD)hasgoneintothestageofpracticalstudy'sincePioneerC0.reportedthefirstc0mmercialproductoforganicgreenELdispla}'usingSma1lm0lecules1.AsOTFELDhasmanyadvantagessuchasactiveemission-highbrightness.l0wdrivingv0ltage,wideviewingangle,Iightweight,andpotentiall0wcost,itisat-tractingmuchattenti0nasacandidatef0rnewflatpaneldisplay.However.therearemanysubjectst0realizethefullcol0rdisplays.The0rganicredandbIueELdisplaysarethebasicessentialt0reaIizefull…     

Quantum transport in complex systems

We derive the influence function and the effective dynamics of a quantum systems coupled to a chaotic environment, using very general parametric and banded random matrices to describe the quantum properties of a chaotic bath. We find that only in certain limits the thermalization can result from the environment. We study the general transport problems including escape, fusion and tunneling (fission). Presented by D. Kusnezov at the International Conference on “Atomic Nuclei and Metallic Clusters”, Prague, September 1–5, 1997.     

分布式本征型法布里-珀罗传感器的研究

本文介绍了一种单模-多模-单模结构的本征型法布里-珀罗传感器, 通过对传感器中渐变型多模光纤的光场分布进行分析和仿真, 实现了传感器腔长的优化设计, 大大降低了插入损耗, 增强了传感器复用能力. 实验证明串联复用中的单个传感器的优化后的插入损耗从4 dB减少至0.83 dB, 多个级联复用时损耗变化平缓, 温度测试结果表明级联的12个传感器均具有较好的灵敏度和线性度.     

Variational formula related to the self‐affine Sierpinski carpets

We consider those subsets of the self‐affine Sierpinski carpets that are the union of an uncountable number of sets each of which consists of the points with their location codes having prescribed group frequencies. It is proved that their Hausdorff dimensions equal to the supremum of the Hausdorff dimensions of the sets in the union. The main advantage is that we treat these subsets in a unified manner and the value of the Hausdorff dimensions do not need to be guessed a priori.     

Prenylated Indole Alkaloid Derivatives from Marine Sediment‐Derived Fungus Penicillium paneum SD‐44

Three new prenylated indole alkaloids, including two β‐carbolines, penipalines A and B ( 1 and 2 , resp.), and one indole carbaldehyde derivative, penipaline C ( 3 ), as well as two known indole derived analogs, 4 and 5 , were isolated from the deep‐sea‐sediment derived fungus Penicillium paneum SD‐44 cultured in a 500‐l bioreactor. The structures of the new compounds were determined on the basis of 1D‐ and 2D‐NMR spectroscopy, as well as by high‐resolution mass spectrometry. The new compounds 2 and 3 showed potent cytotoxic activities against A‐549 and HCT‐116 cell lines.     

Synthesis of Biaryls via Pd-Catalyzed Decarboxylative Coupling of Substituted Benzoic Acids with Phenylboronic Acids

A Pd-catalyzed decarboxylative coupling of substituted benzoic acids with phenylboronic acid has been developed. Under the optimized conditions, a variety of substituted benzoic acids were found to undergo decarboxylative coupling with various phenylboronic acids to give the desired unsymmetrical biaryls in good yields.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resource(s): Full experimental and spectral details.]     

Excellent Capacitive Performance of a Three‐Dimensional Hierarchical Porous Graphene/Carbon Composite with a Superhigh Surface Area

Three‐dimensional hierarchical porous graphene/carbon composite was successfully synthesized from a solution of graphene oxide and a phenolic resin by using a facile and efficient method. The morphology, structure, and surface property of the composite were investigated intensively by a variety of means such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), N₂ adsorption, Raman spectroscopy, and Fourier transform infrared spectroscopy (FTIR). It is found that graphene serves as a scaffold to form a hierarchical pore texture in the composite, resulting in its superhigh surface area of 2034 m²g^?1, thin macropore wall, and high conductivity (152 S m^?1). As evidenced by electrochemical measurements in both EMImBF₄ ionic liquid and KOH electrolyte, the composite exhibits ideal capacitive behavior, high capacitance, and excellent rate performance due to its unique structure. In EMImBF₄, the composite has a high energy density of up to 50.1 Wh kg^?1 and also possesses quite stable cycling stability at 100 °C, suggesting its promising application in high‐temperature supercapacitors. In KOH electrolyte, the specific capacitance of this composite can reach up to an unprecedented value of 186.5 F g^?1, even at a very high current density of 50 A g^?1, suggesting its prosperous application in high‐power applications.     

A New Approach to Prepare Efficient Blue AIE Emitters for Undoped OLEDs

Two aggregation‐induced emission active luminogens (TPE–pTPA and TPE–mTPA) were successfully synthesized. For comparison, another six similar compounds were prepared. Because of the introduced hole‐dominated triphenylamine (TPA), fluorene groups with high luminous efficiency, and unconjugated linkages, the π conjugation length of the obtained luminogens is effectively restricted to ensure their blue emission. The undoped organic light‐emitting diodes based on TPE–pTPA and TPE–mTPA exhibited blue or deep‐blue emissions, low turn‐on voltages (3 V), and high electroluminescence efficiencies with L_max, η_C,max, and η_P,max values of up to 26 697 cd m^?2, 3.37 cd A^?1, and 2.40 Lm W^?1.     

Studying the fine microstructure of the passive film on nanocrystalline 304 stainless steel by EIS,XPS, and AFM

The fine microstructure of the passive films on nanocrystalline (NC) and coarse crystalline (CC) 304 stainless steels (SSs) in 0.5 M H₂SO₄ were investigated by electrochemical impedance spectroscopy (EIS), X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM). The results indicate that the passive film on both CC and NC SSs exhibits a two-layer microstructure consisting of a compact inner layer and a porous outer layer. Some hydrated compounds (HC) were present in the porous outer layer of NC SS but not CC SS in 0.5 M H₂SO₄ solution. The pores in the outer layer of the NC SS were observed to be in the nanoscale by AFM. HC filling of the pores in the passive film on NC SS may occur due to capillary forces endowed by the nanosize pores. XPS analysis of the passive films on both CC and NC SSs, however, does not show such a composition difference which is attributed to dehydration occurring in the XPS vacuum chamber. Both the inner and outer layers of the NC SS were determined by EIS analysis to be more compact and protective than the corresponding films on CC SS as evidenced by the lower Q value, higher n, and much higher R value in the corresponding layer.     

三次采油耐温抗盐聚合物的合成与评价

以丙烯酰胺(AM)、2-丙烯酰胺基-2-甲基丙磺酸(AMPS)和氢氧化钠(Na OH)为原料,采用过硫酸铵[(NH4)2S2O8]、亚硫酸钠(Na2SO3)和四甲基脲[N(CH3)2CON(CH3)2]作为新型复合引发体系,通过共聚后水解工艺,合成了高分子量三元共聚物(AM-AANa-AMPSNa).考察了引发剂用量、单体浓度、p H和引发温度对共聚物黏均分子量的影响.确定最优条件为:引发剂用量0.035%,单体质量浓度为25%,介质p H 7,引发温度0℃.通过红外光谱和核磁碳谱表征了其结构,并系统评价了其理化性能指标、黏弹性、注入性和驱油性能.结果表明,该共聚物较高分子量部分水解聚丙烯酰胺(HPAM)具有更优异的耐温抗盐性能.其黏均相对分子量达到3000万以上,在胜利油田III型盐水中,浓度1500 mg/L,温度85℃条件下,溶液表观黏度达到17.7 m Pa s,岩心驱油实验在水驱采收率51.8%基础上,可再提高15.8%.上述性能表明,该高分子量三元共聚物有望应用在高温高盐油藏三次采油技术中.