Simultaneous enhancement of the efficiency and stability of organic solar cells using PEDOT:PSS grafted with a PEGME buffer layer

We report a simple processing method to simultaneously improve the efficiency and stability of organic solar cells (OSCs). Poly(4-styrene sulfonate)-doped poly(3,4-ethylenedioxy-thiophene (PEDOT:PSS), widely used as hole transport layer (HTL) in OSCs, tends to accelerate the degradation of devices because of its hygroscopic and acidic properties. In this regard, we have modified PEDOT:PSS to reduce its hygroscopic and acidic properties through a condensation reaction between PEDOT:PSS and poly(ethylene glycol) methyl ether (PEGME) in order to improve the efficiency and stability of OSCs. As a result, the power conversion efficiency (PCE) increased by 21%, from 2.57% up to 3.11%. A better energy level alignment by the reduced work function of the modified PEDOT:PSS with a highest occupied molecular orbital (HOMO) level of poly(3-hexylthiophene-2,5-diyl) (P3HT) is considered the origin of the improved the efficiency. The half-life of OSCs with PEDOT:PSS modified with PEGME buffer layer also increased up to 3.5 times compared to that of devices with pristine PEDOT:PSS buffer layer.     

二嗪磷缩合工艺研究进展

综述了有机磷杀虫剂二嗪磷的缩合工艺研究进展。     

EXPERIMENTAL STUDIES OF NUCLEATION PHENOMENA WITHIN THERMAL BOUNDARY LAYERS—INFLUENCE ON CHEMICAL VAPOR DEPOSITION RATE PROCESSES

In carrying out partial vapor condensations using actively cooled surfaces it is known that 'mist' formation can occur within thermal boundary layers (Rosner and Epstein, 1968), dramatically modifying total deposition fluxes. Using a combination of flash-evaporation (Rosner and Liang, 1986) and laser probing techniques, we report new experimental results on binary alkali salt (K₂SO₄ + Na₂SO₄) deposition from combustion gases showing that the deposition rate of potassium sulfate first increases with the addition of sodium sulfate until the concentration of Na₂SO₄ reaches a (target surface temperature dependent) 'threshold' value. Further increases in the concentration of Na₂SO₄ dramatically decrease the total deposition rate of K₂SO₄, implying that potassium sulfate-containing microdroplets are formed within the thermal boundary layer, which, despite their thermophoretic drift toward the target, are not collected as effectively as the 'parent' K₂SO₄-vapor species. Laser light scattering measurements clearly reveal that suspended particles exist near the deposition surface under these conditions. Our experimental results on mass transfer rate and light scattering are consistent with those predicted using laminar boundary layer theory (Castillo and Rosner, 1989b) coupling both binary salt vapor deposition with particle vapor scavenging and deposition. Comparisons of our observed mist onset conditions (implying critical supersaturations near unity) with those expected using homogeneous nucleation theory suggest that the binary alkali sulfate mist nucleation mechanism is, instead, heterogeneous, even in our relatively 'clean' combustion products. Because of the; well-known vapor pressure reduction phenomenon associated here with the formation of non-ideal solutions, binary systems are shown to provide convenient 'vehicles' to investigate BL mist formation onset conditions and CVD-rate consequences without requiring the more extreme surface coolings characteristic of unary condensible vapor systems. An understanding of this dramatic phenomenon, obtained via such laboratory experiments and calculations, will allow its inclusion in future deposition rate calculations of engineering importance.     

三羟甲基丙烷缩合工艺的研究

介绍了三羟甲基丙烷的缩合反应机理及在缩合反应中所发生的副反应，用反应动力学理论讨论了影响缩合反应的各种因素，并列出了在40L反应釜中所进行的缩合试验结果，提出了缩合的最佳工艺条件，结合国内外生产装置的实际，提出了采用最佳缩合工艺条件所需进行的改造措施，以有效地降低原料消耗和提高产品质量。     

APPLICATION OF LINEARIZED MODELS OF MULTICOMPONENT MASS TRANSFER FOR CALCULATION OF EVAPORATION-CONDENSATION PROCESS IN TERNARY SYSTEMS

Results of calculations based on a linearized multicomponent mass transfer theory developed by Burghardt and Krupiczka are compared with experimental data of Modine for condensation-evaporation process in ternary systems. These data have been obtained for acetone-benzene-nitrogen and acetone-benzene-helium in a welted wall column. Models I and II, which take into account diffusional interactions of components in a mullicomponent mixture show good agreement with the experiments as well as with other calculation methods (Krishna-Standart and Toor-Stewart-Prober). When multicomponent mass transfer occurs in the presence of inert species, a straightforward Model II is recommended. Model I, which is more universal, requires some iterative calculations with respect to the sum of mass fluxes. According to theoretical considerations the latter model is limited to the case of low total mass flux. The results of calculations for the systems studied were reasonably good though the total mass fluxes were not small. The calculation procedure based on the presented linearized models are convergent to the proper solutions in contrast to the Krishna-Standart Model IV which in some cases can be unstable.     

In situ polycondensation of amino acid modified liposomes and their properties

Three amphiphilic amino acids based on glutamic acid, i.e. S-[1-carboxy-2-([N-bistetradecyl- -glutamate]carbon-yl)ethyl]cysteine (1), S-[1-carboxy-2-([N-bishexadecyl- -glutamate]carbonyl)ethyl]cysteine (2), S-[1-carboxy-2-([N-bis-octadecyl- -glutamate]carbonyl)ethyl]cysteine (3), were synthesized. The aggregation behavior of them in water or buffer solution was studied. It was found that upon hydration and sonication in water, they could form stable liposomes. This kind of amino acid modified liposome was then polycondensed locally on the liposome surface to form a polypeptide-surfaced liposome and the peptide formation was detected by Fr-IR, GPC, etc. The effect of polycondensation of amino acid on the properties of liposomes were studied by detecting the phase transition temperatures with DSC or measuring the leakage of the encapsulated fluorescent probe from the liposomes. It was observed that the phase transition temperatures of the peptide liposomes moved down and the polycondensation of amino acid moieties obviously increased the leakage of the encapsulated molecules.     

镁铝复合氧化物催化剂气相法合成异佛尔酮

研究了镁铝复合氧化物存在下的丙酮综合合成异佛尔酮的常压气相反应以及催化剂的制备，考察了催化剂的组成和反应温度等对反应温度等对反应的影响，从而确定了较适于工业化投产的反应条件。     

Particularities of condensation of atoms with increased kinetic energy

Novel universal method for measurement of the condensation coefficient α is developed. Using this method, noticeable difference between measured (α≈0.8) and expected (α≈1) values of the condensation coefficient for sputtered Cr atoms was revealed for the first time. The effect is assumed to be a result of considerable elevation of the surface temperature during atomic condensation induced by the energy delivered to the condensation surface by sputtered atoms and from the plasma.     

水平微肋管内冷凝换热特性实验关联式的研究进展

概述目前国内、外空调制冷行业中普遍采用的水平微肋管内冷凝换热特性的实验关联式及其影响因素,指出正确地选用实验关联式,为空调制冷行业中冷凝器的优化设计及其制造提供可靠的依据.     

Towards robust multi-cue integration for visual tracking

Abstract. Even though many of today's vision algorithms are very successful, they lack robustness, since they are typically tailored to a particular situation. In this paper, we argue that the principles of sensor and model integration can increase the robustness of today's computer-vision systems substantially. As an example, multi-cue tracking of faces is discussed. The approach is based on the principles of self-organization of the integration mechanism and self-adaptation of the cue models during tracking. Experiments show that the robustness of simple models is leveraged significantly by sensor and model integration.