An Electron Spin Resonance Study of Evolution of Organic Free Radicals in Irradiated Pepper During Heat Treatment

ABSTRACT: The thermal evolution behavior of the organic free radicals induced in irradiated black pepper was studied by electron spin resonance spectroscopy. To analyze the time-dependent evolution process, we used the theory of transient phenomena, that is, an ordinal differential equation, as well as the nonlinear least squares numerical method. We found that the radical evolution that occurred in the irradiated pepper obeys a single exponential function and yields a unique time constant. The evolution of the organic free radical undergoes a simple reaction process of a single radical species.     

使用热反应型水溶性聚氨酯F-2840E提高纯棉织物"三防"效果

通过试验验证了热反应型水溶性聚氨酯F-2840E可提高“三防”（拒水、拒油、拒污）助剂TG-410H的使用性能，可提高TG-410H等部分有机氟系“三防”整理剂的耐洗性和“三防”效果，减少了“三防”助剂的用量．     

Study on Preparation and Application of Ti／Si Complex Zeolite

A Ti/Si complex zeolite has been prepared. X-ray diffraction and infrared spectrometry study has shown that two structures, namely the ZSM-5 and MCM-41, exist in the sample. BET tests have revealed that the complex zeolite contains regular mesopores of 2.6 nm. Ultraviolet spectrometry analysis has shown that the Ti species exist in the zeolite skeleton in the form of tetra-coordinate valence. The Ti/Si complex zeolite (TS-1/Ti-MCM-41) has apparently improved catalytic activity with respect to the macromolecular organic compound oxidation as compared to individual components of either Ti or Si containing zeolites (TS-1 and Ti-MCM-41).     

海洋钻井液有机物添加剂生物降解性评价

随着海洋石油的勘探开发，钻井液有机添加剂不可避免地进入海洋．因此在海洋勘探开发过程中应选择环保性能好，即生物降解性能好的有机物添加剂。用累计耗氧量法测定了海洋钻井液有机添加剂的生物降解性，研究评价了有机添加剂的生物降解规律和机理，探讨了有机物生物降解性同其化学结构的内在联系，为海洋勘探开发过程中选择环保性能好的有机物添加剂提供理论依据。总结实验结果发现：淀粉类(如DFD-140和FI-E1等)最容易生物降解；其次是纤维素类(如MV-CMC等)和烯类单体聚合物(如PAM和PHP)；而沥青类、两性离子类则难以生物降解，有的甚至对生物降解起抑制作用。     

Influence of Shaping Condition on Etherification Performance of Hβ Zeolite

Etherification reaction of FCC light gasoline over Hβ zeolite was investigated to decrease the light olefins in motor gasoline while enhancing octane. Etherification activity of several molecular sieve catalysts for FCC light gasoline was studied in a fixed-bed reactor. The influence of pore-enlarging agent (PEG) with different molecular weight, binder (γ-Al₂O₃), and peptizing agent (HNO₃) in the shaping process on etherification activity of Hβ zeolite was studied. The impregnating ways of precursor of oxides and the order of extruding and impregnating were also investigated. The results show that the activity of extruded Hβ zeolite before impregnating precursor of oxides is higher than the reverse order. The best shaping condition obtained was PEG-4000 10%, γ-Al₂O₃ 20%, and HNO₃ 10%. At the optimal reaction condition, the conversion of tert-olefins reached the peak. 62.93%, the yield of TAME, is also high and the technology can be applied to industry as well.     

剖析全板电镀镍金发白现象

简要介绍了全板电镀镍金加工过程中镀金面发白现象及改善措施。特别是针对高位发白(或粗糙)的产生原因和处理过程进行较为详细的描述,并对工艺在此处理过程中存在问题进行了简要剖析。     

The Fabrication and Characterization of Single‐Component Polymeric White‐Light‐Emitting Diodes

By using Ni⁰‐mediated polymerization, we have systematically synthesized a series of fluorene‐based copolymers composed of blue‐, green‐, and red‐light‐emitting comonomers with a view to producing polymers with white‐light emission. 2,7‐Dibromo‐9,9‐dihexylfluorene, {4‐(2‐[2,5‐dibromo‐4‐{2‐(4‐diphenylamino‐phenyl)‐vinyl}‐phenyl]‐vinyl)‐phenyl}‐diphenylamine (DTPA), and 2‐{2‐(2‐[4‐{bis(4‐bromo‐phenyl)amino}‐phenyl]‐vinyl)‐6‐tert‐butyl‐pyran‐4‐ylidene}‐malononitrile (TPDCM) were used as the blue‐, green‐, and red‐light‐emitting comonomers, respectively. It was found that the emission spectra of the resulting copolymers could easily be tuned by varying their DTPA and TPDCM content. Thus with the appropriate red/green/blue (RGB) unit ratio, we were able to obtain white‐light emission from these copolymers. A white‐light‐emitting diode using the polyfluorene copolymer containing 3 % green‐emitting DTPA and 2 % red‐emitting TPDCM (PG3R2) with a structure of indium tin oxide/poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonic acid)/PG3R2/Ca/Al was found to exhibit a maximum brightness of 820 cd m^–2 at 11 V with Commission Internationale de L'Eclairage (CIE) coordinates of (0.33,0.35), which are close to the standard CIE coordinates for white‐light emission (0.33,0.33).     

A Light‐Blue Phosphorescent Dendrimer for Efficient Solution‐Processed Light‐Emitting Diodes

We describe the preparation of a dendrimer that is solution‐processible and contains 2‐ethylhexyloxy surface groups, biphenyl‐based dendrons, and a fac‐tris[2‐(2,4‐difluorophenyl)pyridyl]iridium(III ) core. The homoleptic complex is highly luminescent and the color of emission is similar to the heteroleptic iridium(III ) complex, bis[2‐(2,4‐difluorophenyl)pyridyl]picolinate iridium(III ) (FIrpic). To avoid the change in emission color that would arise from attaching a conjugated dendron to the ligand, the conjugation between the dendron and the ligand is decoupled by separating them with an ethane linkage. Bilayer devices containing a light‐emitting layer comprised of a 30 wt.‐% blend of the dendrimer in 1,3‐bis(N‐carbazolyl)benzene (mCP) and a 1,3,5‐tris(2‐N‐phenylbenzimidazolyl)benzene electron‐transport layer have external quantum and power efficiencies, respectively, of 10.4 % and 11 lm W^–1 at 100 cd m^–2 and 6.4 V. These efficiencies are higher than those reported for more complex device structures prepared via evaporation that contain FIrpic blended with mCP as the emitting layer, showing the advantage of using a dendritic structure to control processing and intermolecular interactions. The external quantum efficiency of 10.4 % corresponds to the maximum achievable efficiency based on the photoluminescence quantum yield of the emissive film and the standard out‐coupling of light from the device.     

铜硅取代的酞青材料LB膜气敏传感器的研究

采用ＬＢ膜技术对沉积在石英晶振的铜硅取代的酞青材料的气体敏感性进行了系统研究，结果表明，该方法所获得的敏感膜敏感度高，反应迅速，稳定性较好。