The effect of crystallinity in donor groups on the performance of photovoltaic devices based on an oligothiophene-fullerene dyad

Organic photovoltaic devices based on an oligothiophene-fullerene dyad mixed with either an oligothiophene as donor or [6,6]-phenyl-C61-butyric acid methyl ester (PCBM) as acceptor were fabricated to improve charge carrier transport in the films. The origin of the device performance dependence on the mixing ratios was studied by atomic force microscopy and UV-vis absorption spectra and differential scanning calorimetry measurements. We found that the addition of the oligothiophene molecules improved the crystallinity of the donor groups in the film, resulting in a 20% increase in fill factor, while the addition of PCBM slightly lowered the crystallinity, thereby reducing the fill factor.     

Estimation of uncertainties on dose calculations of the 99mTc-MDP-injected patients in nuclear medicine

The internal exposures of the patients in nuclear medicine can be calculated based on the equations and data in ICRP Publications 53 and 80. Physical and biological parameters are used for the calculation, and both include uncertainties. Physical parameters can be considered as more precise than biological parameters, so that uncertainties originated from biological parameters are more important. Absorbed fractions (AFs) have been calculated by Monte-Carlo method using medical internal radiation dose (MIRD)-type mathematical phantoms. They depend on the shapes and sizes of the phantoms used in simulations. For estimating shape- and size-related uncertainties, AFs of pairs of source regions and target tissues of the patient-injected 99mTc-MDP were calculated by using EGS4 codes and a voxel phantom of Japanese male. By simply resizing the voxels of the phantom, the dependencies of size for AFs were calculated, and the uncertainties caused by the cumulated activities in source regions were also estimated by assuming these parameters distributions as Gaussian.     

Microstructure control of porous alumina film using aqueous sol containing poly(ethylene glycol)

To fabricate a porous and thick alumina film with large surface area on a substrate by a dip-coating technique, we prepared an aqueous sol containing poly(ethylene glycol) (PEG). The sol was prepared by hydrolysis of aluminum (III) isopropoxide with large amount of water and following peptization to colloidal particle from precipitate. The films were coated on the glass substrate by the dip-coating and then calcined at 500 °C. The maximum thickness of the film prepared by one-run dip-coating was ca. 1,000 nm. The film was an aggregate of alumina particles with a diameter of 30–50 nm and pores were interstices between the particles. The porosity of alumina film can be controlled in the range of 40–59% by changing PEG concentration in the dip-coating solution.     

ESR spectroscopic evaluation of void parts in microheterogeneously crosslinked monomethacrylate/dimethacrylate resins by using copper(II) tetraphenylporphyrin spin probe

As part of continuing studies concerned with the elucidation of three‐dimensional network formation mechanism in the free‐radical crosslinking polymerization of multivinyl compounds, void parts in microheterogeneously crosslinked monomethacrylate/dimethacrylate resins were evaluated by ESR spectroscopy. Thus, the usefulness of copper(II) tetraphenylporphyrin (CuTPP) as a spin probe was verified for the evaluation of void parts under specified polymerization conditions. The correlation between ESR spectra and microheterogeneity of networks formed under various conditions was examined by changing the factors influencing resultant network structures, including monomer concentration, crosslinker content and flexibility of network segments. The mobility restriction of CuTPP by network formation was reduced noticeably under the conditions introducing the inhomogeneous network as a result of the exclusion of CuTPP from densely crosslinked network parts to void ones in cured resins.     

On-demand patterning of protein matrixes inside a microfluidic device

On-demand immobilization of proteins at specific locations in a microfluidic device would advance many types of bioassays. We describe a strategy to create a patterned surface within a microfluidic channel by electrochemical means, which enables site-specific immobilization of protein matrixes and cells under physiological conditions, even after the device is fully assembled. By locally generating hypobromous acid at a microelectrode in the microchannel, the heparin-coated channel surface rapidly switches from antibiofouling to protein-adhering. Since this transformation allows compartmentalizing of multiple types of antibodies into distinct regions throughout the single microchannel, simultaneous assay of two kinds of complementary proteins was possible. This patterning procedure can be applied to conventional microfluidic devices since it requires only some electrodes and a voltage source (1.7 V, DC).     

Ni-Ti系中γ、η、β相平衡的实验与热力学解析

采用实验和热力学解析的方法对Ｎｉ－Ｔｉ系中γ,η,β之间的相平衡进行了研究,图图为镍基高温合金的设计和组织控制提供基础数据。γ／γ＋η,η＋β／β相界与文献报道一致,但η相的存在区域有一定的万分范围,特别是γ＋η／η界面上钛的成分随温度而变化。     

Enhanced continent mechanism of tapered ileum by extramural support from pouch-abdominal wall: an experimental study in dogs

PURPOSE: To construct a reliable continent tube, which is easy to catheterize, we created and evaluated a new continent cutaneous diversion using a tapered ileum combined with extramural support from the pouch-abdominal wall. MATERIALS AND METHODS: Six dogs underwent a procedure in which two ileal segments were tapered and anastomosed to the ileal pouch. One of the segments (continent) was placed between the back surface of the rectus muscle and the wall of the ileal pouch creating a continent tube. The other segment (control) was brought out into the abdominal skin directly without any support from the pouch-abdominal wall. Urodynamic and radiological studies were carried out postoperatively in all dogs. RESULTS: In the continent tubes, the maximum closure pressure with a full pouch was significantly higher than those with an empty pouch (p<0.01). The maximum closure pressures of the continent tubes were significantly higher than those of the control tubes when the pouch was empty (p<0.01). The leak point pressures of the continent tubes were significantly higher than those of the control tubes (p<0.001). In all dogs, the retrograde radiogram of the continent tubes showed perfect canalization without stenosis. CONCLUSION: This study suggests that the continent mechanism of tapered ileum can be greatly enhanced by fixing it between the abdominal and pouch walls, also allowing easy catheterization in contrast to the submucosal tunnel technique.     

Compact system of wavelength-tunable femtosecond soliton pulsegeneration using optical fibers

Using passively mode-locked femtosecond (fs) fiber laser and polarization maintaining fibers, the compact system of wavelength-tunable femtosecond (fs) fundamental soliton pulse generation is realized. The monocolored soliton pulse, not multicolored ones, with the ideal sech² shape is generated, and its wavelength can be linearly shifted by varying merely the fiber-input power in the wide wavelength region of 1.56-1.78 μm for a 75-m fiber. The soliton pulses of less than 200 fs are generated with the high conversion efficiency of 75%-85%. This system can be widely used as a portable and practical wavelength-tunable fs optical pulse sources     

Ni-Al-Cr系富Ni区相平衡研究

用热扩散偶实验和热力学模型研究和计算了 Ｎｉ－Ａｌ－Ｃｒ系富 Ｎｉ区γ,ａ,γ’和β相的相平衡。用规则溶体和亚点阵模型计算了该体系９００℃－１３００℃区间的等温截面,计算结果与实验值相符合。     

Spatiotemporally Controllable Chemical Delivery Utilizing Electroosmotic Flow Generated in Combination of Anionic and Cationic Hydrogels

Spatiotemporally controlled chemical delivery is crucial for various biomedical engineering applications. Here, a novel concept of electrically controllable delivery utilizing electroosmotic flow (EOF) generated in a combination of anionic and cationic hydrogels (A- and C-hydrogels) is reported. The unique advantages of the A/C-hydrogel combination are demonstrated utilizing a flexible sheet-shaped and a thin tubular devices. Since the directions of EOF in the A- and C-hydrogels are opposite to each other, the ionic current for EOF generation flows inside the delivery devices, enabling chemical delivery without accompanying external ionic current that could stimulate target cells and tissues. A thin tubular device, which can be inserted into narrow in vivo structures and be integrated with other flexible devices, exhibits high robustness and repeatability thanks to the flexibility and water retentivity of hydrogels. The EOF devices with A/C-hydrogels combination show high controllability superior to the pumping with a conventional syringe; the volumetric flow rate is able to be controlled proportionally to the current applied, for example, ≈0.4 µL (mA min)⁻¹ for the tubular device. The developed EOF-based devices are versatile for delivery of most chemicals regardless of their charge and size, and have great potential for both biomedical researches and therapeutics.