Multi-color light-emitting transistors composed of organic single crystals

We report a novel concept for multi-color light emission from an ambipolar organic single-crystal transistor using natural optical waveguides, the self-absorption effect, Davydov splitting and the unique alignment of the transition dipole moments. We used 9,10-bis-(2,2-diphenylvinyl)-anthracene single crystals to produce blue and green light from identical single-crystal transistors. We also observed red light, which corresponds to the emission from in-gap states that are caused by impurities. Importantly, each of these different colors corresponds to a distinguishable light polarization, which enables us to tune the emission color by using a light polarizer.     

Spectroscopic properties of Er doped and Er, Nd codoped fluoride glasses under simulated sunlight illumination

We investigated the fluorescence characteristics of Er codoped Nd doped ZBLAN glasses proposed for solar pumped fiber laser (SPFL) under simulated sunlight. Er is used as a sensitizer because it absorbs a part of the ultraviolet and visible light where is no absorption of Nd. Under simulated sunlight illumination, Er singly doped fluoride glass displayed four emission bands with peaks at 550, 848, 977 and 1533 nm attributed to the ⁴S_3/2-⁴I_15/2, ⁴S_3/2-⁴I_13/2, ⁴I_11/2-⁴I_15/2 and ⁴I_13/2-⁴I_15/2 electronic transitions of Er, respectively. The quantum efficiency measurement was carried out using an integrating sphere and under the simulated sunlight excitation showed a maximum of 73% for 0.5 mol.% of ErF₃ in ZBLAN glass. In Nd, Er codoped fluoride glass, the 1.05 μm emission of Nd was observed under 380 nm excitation what supposes the energy transfer from Er to Nd in ZBLAN glasses as Nd has no absorption at the wavelength. Er, Nd codoped fluoride glasses are promising as a sensitized laser media for solar pumped fiber lasers.     

Stable and controlled amphoteric doping by encapsulation of organic molecules inside carbon nanotubes

Single-walled carbon nanotubes (SWNTs) have strong potential for molecular electronics, owing to their unique structural and electronic properties. However, various outstanding issues still need to be resolved before SWNT-based devices can be made. In particular, large-scale, air-stable and controlled doping is highly desirable. Here we present a method for integrating organic molecules into SWNTs that promises to push the performance limit of these materials for molecular electronics. Reaction of SWNTs with molecules having large electron affinity and small ionization energy achieved p- and n-type doping, respectively. Optical characterization revealed that charge transfer between SWNTs and molecules starts at certain critical energies. X-ray diffraction experiments revealed that molecules are predominantly encapsulated inside SWNTs, resulting in an improved stability in air. The simplicity of the synthetic process offers a viable route for the large-scale production of SWNTs with controlled doping states.     

REX-J: Japanese referring expression corpus of situated dialogs

Identifying objects in conversation is a fundamental human capability necessary to achieve efficient collaboration on any real world task. Hence the deepening of our understanding of human referential behaviour is indispensable for the creation of systems that collaborate with humans in a meaningful way. We present the construction of REX-J, a multi-modal Japanese corpus of referring expressions in situated dialogs, based on the collaborative task of solving the Tangram puzzle. This corpus contains 24 dialogs with over 4?h of recordings and over 1,400 referring expressions. We outline the characteristics of the collected data and point out the important differences from previous corpora. The corpus records extra-linguistic information during the interaction (e.g. the position of pieces, the actions on the pieces) in synchronization with the participants’ utterances. This in turn allows us to discuss the importance of creating a unified model of linguistic and extra-linguistic information from a new perspective. Demonstrating the potential uses of this corpus, we present the analysis of a specific type of referring expression (“action-mentioning expression”) as well as the results of research into the generation of demonstrative pronouns. Furthermore, we discuss some perspectives on potential uses of this corpus as well as our planned future work, underlining how it is a valuable addition to the existing databases in the community for the study and modeling of referring expressions in situated dialog.     

Clustering triple microbeads in a dynamic microarray for timing-controllable bead-based reactions

In this study, we developed a dynamic microfluidic device that enables the clustering of three different types of microbeads in a trapping spot and the rearrangement of contacting modes of the clustered microbeads. To achieve these two functions, two features are added to the conventional dynamic microfluidic device. (1) To trap multiple beads, an extended trapping spot with sub-by-pass channels and a valve was employed. (2) To rearrange the clustered microbeads, trapping spots that work only by backward flow were added. The design of the microfluidic device was realized by calculations based on fluidic resistance. By using the designed device, we successfully clustered different types of hydrogel microbeads including target materials, and observed reactions between clustered microbeads. In addition, by rearranging the contacting modes of the clustered microbeads, the reaction could be initiated/terminated at the desired time. We found that this dynamic microfluidic device is applicable to the quantitative analysis of chemical reactions between small amounts of multiple materials.     

Characterization of Spaghetti Prepared Under Different Drying Conditions

Spaghetti dried at low (max. 50 °C), high (max. 70 °C), and very high (max. 85 °C) temperatures were characterized by their color, surface structure, rupture strength, texture analysis, and sauce retention capacity. The texture and sauce retention capacity were estimated for cooked spaghetti. The color of the spaghetti's methanol extracts, as evaluated through absorbance at 440 and 466 nm, did not depend on the drying temperature. A trend was observed in the surface texture of spaghetti, as estimated by atomic force microscopy and mercury intrusion porosimetry, where the surface was rougher when dried at higher temperatures than at low temperatures. Furthermore, the rupture strength was also higher for the spaghetti dried at higher temperatures. This result can be ascribed to the formation of stronger gluten networks, promoted by denaturation of gluten at the higher temperatures. However, the hardness of cooked spaghetti was not affected by the drying temperature, a result attributable to the action of water sorption to offset any differences in hardness among the spaghettis dried at the 3 different temperatures. The sauce retention capacity of cooked spaghetti was evaluated using a dextran solution as a simulated sauce, and by this method, the capacity of the spaghetti dried at a low temperature was shown to be significantly lower than that of the spaghetti dried at higher temperatures. This can be ascribed to the smoother surface of cooked spaghetti dried at the lower temperature and also to the leakage of amylose onto the surface during cooking.     

Growth behaviour and plasmon resonance properties of photocatalytically deposited Cu nanoparticles

Cu nanoparticles (NPs) were deposited on UV-irradiated TiO(2) in an aqueous solution containing Cu(CH(3)COO)(2) and ethanol by a photocatalytic reaction. Cu NPs on TiO(2) exhibit an extinction (= absorption + scattering + reflection) peak due to localized surface plasmon resonance at around 600 nm initially. The density and size as well as the extinction of Cu NPs increase during the deposition, accompanied by a slight redshift of the peak. Eventually, TiO(2) is mostly covered with coalesced Cu NPs that exhibit a spectrum less characteristic of Cu NPs, but more characteristic of a Cu layer.     

Measurement of Moisture Profiles in Pasta During Rehydration Based on Image Processing

A method using an image processing technique was developed to measure the moisture profile in pasta during its rehydration process. The method is based on the increase in sample color brightness with increasing moisture content. Compared to currently used methods, this method has the advantage that moisture contents around 0.1 kg-H₂O/kg-d.m. can be easily measured at a spatial resolution of 1.6 μm. The moisture profiles obtained by this method suggested that penetration of water into small holes and cracks on the pasta surface, water diffusion in the pasta, and structural relaxation of the protein matrix play important roles in the rehydration mechanism. It was also suggested that starch granule gelatinization prevented water migration into the interior portion of the pasta.     

Properties and Water Sorption Characteristics of Spaghetti Prepared Using Various Dies

Spaghetti was prepared using dies made of different materials. The surface was observed using digital and optical microscopes, and was rougher for the spaghettis prepared using the Teflon, polypropylene, polycarbonate, aluminum, and bronze dies in this order. The extrusion velocity when passing through the die was faster, the bulk density was higher, and the rupture strength was greater for the spaghetti having the smoother surface. The die material did not affect the gelatinization temperature. The water sorption curves in boiling water containing 0.5% (w/v) sodium chloride were also observed. The curves were expressed by an equation of the hyperbolic type except for the early stage of sorption in order to estimate the equilibrium amount of water sorbed based on the bone‐dry sample. The momentarily‐sorbed amount of water, which is a hypothetical quantity to characterize the initial water intake, was estimated by fitting the experimental points within 60 s. The amount was higher for the spaghetti having the rougher surface.     

浸没式平板膜生物反应器处理钞票纸厂废水的中试研究

采用"水解+浸没式平板膜生物反应器"工艺对钞票纸造纸废水进行了中试试验研究,试验了水力停留时间、膜通量、生物系统有机负荷等关键技术参数对处理出水COD等指标的影响,得到较优化的操作条件。当水力停留时间为24 h、生物系统COD有机负荷≤0.4～0.5 kg/(m3.d)和膜通量为0.3 m3/(m2.d)时,膜的跨膜压差增长很慢,可稳定实现出水COD小于50 mg/L的排放要求。