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171.
Ogawa T Uchino T Takahashi D Izumi T Otsuka M 《Drug development and industrial pharmacy》2012,38(11):1390-1393
Objective: In some of drug developments, the amount of bulk drug powder to use in early stages is limited and it is not easy to supply a sufficient drug amount for conventional preparation methods. Therefore, an ultra-small-scale high-shear granulator (less than 5?g) (USG) was developed and applied to small-scale granulation as a pre-formulation. Method: The sample powder consisted of 66.5% lactose, 28.5% microcrystalline cellulose and 5.0% hydroxypropylcellulose. The granules were obtained to agitate 5?g of the sample powder with 1.0?mL of water at 300?rpm for 5?min after pre-powder mixing for 3?min by the USG and the manual hand (HM) methods. Results: The granules were evaluated by the 10% and 90% accumulated particle size and the recoveries of the granules and the powder solid. Median particle size for the USG and the HM methods was 159.2?±?2.3 and 270.9?±?14.9 μm, respectively. The USG method had a narrower particle size distribution than those by the HM method. The recovery of the granules by USG was significantly larger than that by the HM method. Conclusion: Characteristics of all of the granules indicated that the USG method could produce higher quality granules within a shorter time than the HM methods. 相似文献
172.
Tanaka H Hong L Fukumori M Negishi R Kobayashi Y Tanaka D Ogawa T 《Nanotechnology》2012,23(21):215701
Nanoparticles of N,N'-bis(n-alkyl)tetracarbonatenaphthalenediimide (NDI) were adsorbed on single-walled carbon nanotube (SWNT) wires dispersed on a SiO(2) substrate. The electrical properties were measured along the long axis of the SWNTs, and in all cases through the nanoparticles showed rectification in semiconducting I-V curve. The plateau width of the I-V curve through the NDI nanoparticles on metallic SWNTs decreased as the particle size increased, while the rectification ratio increased. The conduction mechanism was changed from tunneling conduction to Schottky-like conduction and their boundary is at about 3 nm diameter. 相似文献
173.
Daisuke Yokoyama Ken‐ichi Nakayama Toshiya Otani Junji Kido 《Advanced materials (Deerfield Beach, Fla.)》2012,24(47):6386-6386
174.
Shingo Wakahara Yuki FuruyaTakayuki Yanagida Yuui YokotaJan Pejchal Makoto SugiyamaNoriaki Kawaguchi Daisuke Totsuka Akira Yoshikawa 《Optical Materials》2012,34(4):729-732
0.1%, 0.5%, 1% and 3% Ce doped scintillation crystals based on NaF-CaF2-LuF3 solid solutions were grown from the melt using Micro-Pulling-Down (μ-PD) method. The grown crystals were transparent and their transmittance was approximately 80% for the wavelengths longer than 320 nm. Concerning the scintillation properties, radio-luminescence peaks of the crystals were detected at approximately 330 nm. The light yield of the crystals was also measured using γ-ray (137Cs and 22Na) as the excitation source. 相似文献
175.
Shera JN Takahashi D Herrera AI Prakash O Sun XS 《Journal of nanoscience and nanotechnology》2010,10(12):7981-7987
Protein nanomaterials at the peptide level have shown great potential for medical applications. Peptides change their morphological conformation because of changes in self-assembly properties when they are exposed to changes in solvent composition or pH. Two 15-residue peptide sequences, KhK (KKKFLIVIGSIIKKK) and Alternating Kh (KFLKKIVKIGKKSII), were designed for the purpose of determining the role of peptide sequence on solution morphology and conformation. KhK solutions exhibited a random coil to helical transition when solvent conditions were changed from water to a trifluorethanol/water solution at acidic pH. Alternating Kh solutions, however, demonstrated primarily random coil character under similar solvent and pH conditions as determined by circular dichroism spectroscopy and 2D-1H-1H nuclear magnetic resonance spectroscopy. At basic pH, circular dichroism spectroscopy and nuclear magnetic resonance spectroscopy analysis demonstrated that random coil character increased at basic pH for KhK, whereas Alternating Kh exhibited an increase in beta-sheet character. Further analysis by transmission electron microscopy showed marked differences in the peptide solution morphology. Peptide particle aggregation and fiber formation were significantly affected by solvent composition and pH values for both peptide sequences. 相似文献
176.
Shaun?D.?Gittard Daisuke?Hojo G.?Kevin?Hyde Giovanna?Scarel Roger?J.?NarayanEmail author Gregory?N.?Parsons 《Journal of Materials Engineering and Performance》2010,19(3):368-373
The antifungal properties of two silver-coated natural cotton fiber structures prepared using a supercritical carbon dioxide
(scCO2) solvent were examined. Scanning electron microscopy confirmed that the scCO2 process may be used to produce cotton fiber textiles with uniform silver nanoparticle coatings. A version of the Kirby-Bauer
disk diffusion test was used to assess the ability of these textiles to inhibit fungal growth. Cotton fabric samples modified
with Ag(hepta) and Ag(cod)(hfac) exhibited measurable zones of inhibition. On the other hand, the uncoated fabric had no zone
of inhibition. Possible applications of antifungal textiles prepared using scCO2 processing include use in hospital uniforms and wound dressings. 相似文献
177.
Epoxy/zirconia hybrid materials were synthesized via in situ polymerization of acetic acid-modified zirconium alkoxide. The reactivity of acetic acid-modified zirconium alkoxide changed with the amount of acetic acid added. In the hybrid materials, the phase structure varied between the homogeneous phase and nanophase separation as the reactivity of zirconium alkoxide changed. At the molecular level, the storage modulus in the rubbery region significantly increased and the peak area of tan δ in the glass-transition temperature region decreased with increasing zirconia contents in the hybrid dispersed zirconia. Additionally, the optical properties of the hybrid materials in the homogeneous phase were better than those in the system with nanophase separation. 相似文献
178.
Hidemitsu Aoki Takuro Masuzumi Makoto Hara Daisuke Watanabe Chiharu Kimura Takashi Sugino 《Thin solid films》2010,518(8):2102-2104
We investigated the properties of boron carbon nitride film containing hydrogen (BCNH film) deposited using tris(dimethylamino)boron as the source gas. The dielectric constant (k) of BCNH film decreases with decreasing radio-frequency plasma power used for deposition, and can be as low as 1.8 at 10 W. Thermal desorption spectroscopy analysis shows that the film contains a large amount of hydrogen. Fourier transform infrared spectroscopy shows an absorption band at 2960 cm−1, attributed to the asymmetrical stretching mode of C-H in the methyl group. It is thought that increasing the number of C-H bonds, which have a low polarizability, can achieve a lower k value. 相似文献
179.
Xinnan ZHANG Takashi IZATO Junzo MUNENOTO Daisuke MATSUSHITA Tetsu YOSHIDA 《Frontiers of Structural and Civil Engineering》2010,4(4):438-449
This paper investigates the staying and moving characteristics of office workers in a non-territorial office using an ultra wide band (UWB) impulse radio sensor network. The differences between office workers’ staying and moving are clarified according to the individual workstation type that they select. The study determines the characteristics of each type of workstation. By clarifying office workers’ preference for staying and moving with regard to individual workstation types and office worker post, the reasons why office workers in different posts tended to select different types of workstations were revealed. Specifically, leaders tended to select workstations at the “inner meeting corner side” most frequently, as they had a greater need to stay in other areas. In contrast, ordinary staff needed to visit office workers in other areas less often, and as such, they tended to select individual workstations at the “middle meeting corner side.” Barring this, they tended to select individual workstations at the “middle corridor side” or “outer-meeting corner side.” Temporary staff members had little need to visit or stay at other places so they tended to select individual workstations at the “window side,” which is seldom visited or stayed at by other office workers and they could be disturbed less often from their solo work. 相似文献
180.
A field survey on energy consumption by hot water supply and cooking was conducted in two cities in China, Nanjing, and Hefei. In each city, 5 housing complexes were selected, and approximately 100 or 200 residential units were selected from each of them. The following items were surveyed: (1) fundamental information, such as number of family members, data on residents, etc., (2) bathing style, and (3) frequency of cooking and cooking time. Most of the residents take showers seven times a week in the summer, but less frequently in the winter. In contrast, the frequency of taking baths increases to several times a week during the winter, compared with 0 or 1 times a week in the summer. These results differ slightly depending on the heating and cooling systems used in the houses. The frequency with which people cook in their own houses ranges from 4 to 7 times a week, which means that “eating out” is relatively frequent, although the result differs significantly among the housing complexes. Distribution of the cooking time has usually two peaks at 20 to 30 min and 50 to 60 min (or 30 to 40 min and longer than 60 min) for lunch and dinner, respectively. The high energy consumption for cooking might be due to the long cooking time. 相似文献