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71.
Matsuo T. Inaba A. Yamamuro O. Hashimoto M. Sotani N. 《Journal of Thermal Analysis and Calorimetry》2002,69(3):1015-1020
An experimental set-up is described in which the temperature of a piece of rubber is measured with thin wire thermocouples.
It measures and records the temperature change of the rubber as it heats and cools in response to elongation and contraction.
This mechano-caloric effect arising from the entropy elasticity of rubber represents a reversible thermal process in clear
distinction from most of other heat effects encountered in our daily experience where the irreversibility is inevitably involved.
The demonstration experiment has been proved useful in elementary thermodynamic courses for introducing the entropy concept.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
72.
H. Hasegawa N. Akata H. Kawabata Y. Chikuchi T. Sato K. Kondo J. Inaba 《Journal of Radioanalytical and Nuclear Chemistry》2007,273(1):171-175
7Be deposition fluxes and atmospheric concentrations were measured at Rokkasho Village, Aomori Prefecture, Japan, from 2000
to 2005. It was confirmed that the 7Be deposition fluxes were minimum in summer, and the fallout maximizes in winter. The atmospheric concentration of 7Be was especially low in summer, and high in the other three seasons. A positive correlation was observed between the amount
of precipitation and 7Be deposition. Clear seasonal differences were evident among the ratios of 7Be deposition flux to precipitation amounts in the four seasons. The ratios were especially high in winter, higher than those
in the other three seasons. 7Be deposition flux was estimated by a simple simulation model using atmospheric 7Be concentrations and local meteorological data. As a result, the estimated deposition value was relatively lower than the
measured value in winter. 相似文献
73.
Iwao Ojima Shin-Ichi Inaba Tetsuo Kogure Yoichiro Nagai 《Journal of organometallic chemistry》1973,55(1):C7-C8
Dibromomethyllithium and its homologues RCBr2Li (R = Bu, Me3Si, Br) are prepared by metallation of the corresponding α,α-dibromo compounds with lithium diisopropylamide in THF at low temperature. Various coupling reactions are described (alkylation, hydroxyalkylation). New one-step preparations of α-bromoepoxides and α-bromoketones are reported. 相似文献
74.
The sorption of ion pairs on membrane filters (MFs) has been studied by taking the membrane filter as one of the homogeneous phases. The sorbability of some ionic species and the sorption abilities of different types of MF were evaluated in terms of the sorption constant defined by Ksor,CA = [(C+,A-)f]/[C+][A-], where C+, A- and (C+,A-) refer to the cation, anion and the ion pair, respectively, and f refers to the filter phase. The values of Ksor,CA were determined for many combinations of ionic complexes of cobalt(III) with pyridylazophenols, either as cations or anions, and oppositely charged organic ions having different alkyl chain lengths, with MFs made of different materials: nitrocellulose (NC; Toyo Advantec), acetylcellulose (AC; Fuji Film), regenerated cellulose (RC; Toyo Advantec) and polyethersulphone (PS; Toyo Advantec). For a given cobalt complex ion, the value of log Ksor,CA increased linearly with the increasing number of carbons in the counter ion. Membrane filters made of different materials showed different sorption abilities, the order being NC greater than PS greater than RC greater than AC. It was shown that the surface area of the MF is of greater significance than the volume of the matrix of the MF in determining the sorption constant. 相似文献
75.
Maekawa Y Inaba T Hobo H Narita T Koshikawa H Moon S Kato J Yoshida M 《Chemical communications (Cambridge, England)》2002,(18):2088-2089
Radiation-induced reactions of cinnamic acid derivatives have been examined and compared with photoreactions in the crystalline state; all the reaction products were exactly the same as those of the photoreactions, indicating that the reactions proceed only via the lowest excited state to give [2 + 2] cycloadducts, E/Z isomerization products, or starting molecules. 相似文献
76.
M. Chiba K. Sera M. Hashizume T. Shimoda S. Sasaki O. Kunii Y. Inaba 《Journal of Radioanalytical and Nuclear Chemistry》2004,259(1):149-152
Environmental conditions were evaluated by element concentrations in hair of children living near the Aral Sea. Hair samples were provided by 63 children living near the Sea (K-district), and 143 children living about 600 km from the Sea (Z-district). PIXE was applied for the determination of elemental concentrations. The concentrations of Br, Na, Hg, and Ni were higher in K-district, and those of Al, Ca, Cr, P, S, and Si were higher in Z-district than in the other district, respectively. It is considered that these results reflect the environmental situation. 相似文献
77.
Y. Ohtsuka M. Yamamoto Y. Takaku S. Hisamatsu J. Inaba 《Journal of Radioanalytical and Nuclear Chemistry》2006,268(2):397-403
Summary A
rapid method was developed using ultrafilters with a tangential flow filtering
system for molecular size separation of naturally occurring 210Pb
and 210Po in a freshwater sample. Generally, ultrafiltering of a
large volume water sample for measuring the nuclides was too time consuming and
not practical. The tangential flow filtering system made the filtering time
short enough to adapt for in-situ ultrafiltering the large volume sample. In this
method, a 20 liter water sample was at first passed through the 0.45mm pore size
membrane filter immediately after sample collection to obtain suspended
particle matter [>0.45mm particulate fraction (PRT)]. Two ultrafilters (Millipore
Pellicon 2ò)
were used sequentially. The nuclides in the filtrate were separated into three
fractions: high molecular mass (100 kDa-0.45mm; HMM), low molecular mass (10 k-100 kDa;
LMM) and ionic (<10 kDa; INC) fractions. It took 80 minutes to process the
sample after collection. The cut-off molecular size of each ultrafilter was
confirmed by size exclusion chromatographs (SEC) of the LMN and the HMM
fractions. Adsorption of the nuclides and organic compounds in the sample onto
the ultrafilters was negligibly small. Good reproducibility of the nuclide
concentrations in each fraction was confirmed by repeated experiments. The
method was successfully applied to obtaine the molecular size distributions of 210Pb
and 210Po in an oligotrophic lake, Lake Towada located in the northern
area of Japan.</p>
</p> 相似文献
78.
79.
Dr. Kouzou Matsumoto Sota Kugo Dr. Daisuke Takajo Prof. Dr. Akira Inaba Dr. Yasukazu Hirao Dr. Hiroyuki Kurata Prof. Dr. Takeshi Kawase Prof. Dr. Takashi Kubo 《化学:亚洲杂志》2012,7(1):225-232
A series of tetrahedral oligothiophenes bearing n‐hexyl groups at the α‐positions of the terminal thiophene rings, (n‐C6H13(C4H2S)n)4C (Hex‐TnTM; n=1–4), has been synthesized by Kosugi–Migita–Stille coupling as a key reaction. Thanks to the improved solubility afforded by the terminal n‐hexyl groups, the largest homologue (n=4) was successfully obtained. Whereas the smaller derivatives (n=1, 2) were obtained as liquid substances, the larger derivatives (n=3, 4) were obtained as solids. Hex‐T3 TM partially adopts syn conformations between the adjacent thiophene rings in the crystal, probably owing to the packing force. Hex‐T3 TM not only appeared in the crystalline state but also the amorphous state, which was stable to up to 80 °C. Regardless of the terminal groups, the derivatives of n=2 exhibited a broad fluorescence with large Stokes shifts compared to the corresponding linear analogues, thereby suggesting the presence of intramolecular interactions between the bithiophene moieties. Interactions between terthiophene branches was also suggested in the radical cations of Hex‐T3 TM by cyclic voltammetry measurements. 相似文献
80.