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151.
Miyamura Y Park C Kinbara K Leibfarth FA Hawker CJ Aida T 《Journal of the American Chemical Society》2011,133(9):2840-2843
When poly(isopropylidene diallylmalonate) rich in threo-disyndiotactic sequences (st(rich)-2) was utilized as a cross-linkable ink for microcontact printing, the resultant submicrometer-scale patterns featuring 700 and 300 nm wide stripes were successfully insolubilized while maintaining their high dimensional integrity by heat-induced cross-linking with elimination of CO(2) and acetone. In sharp contrast, although the thermal properties and reactivities of a polymer rich in threo-diisotactic sequences (it(rich)-2) and a polymer having low stereoregularity (2(low)) are little different from those of st(rich)-2, the patterns printed with these reference polymers collapsed considerably upon heating as a result of a volume shrinkage effect. The striking difference between st(rich)-2 and the other two polymers most likely arises from the nanofiber-forming character of st(rich)-2, where the printed stripes are porous and much less affected by the volume shrinkage of individual nanofibers. 相似文献
152.
Aida Taira Toma Takahiro Kanada Satoshi 《Journal of Solid State Electrochemistry》2020,24(6):1415-1425
Journal of Solid State Electrochemistry - It is well known that reducing particle size and/or hollowing the particles improves the electrochemical performance, especially the rate capability, of... 相似文献
153.
Mercedes Casado Laura Altimira Raquel Montero Esperanza Castejón Andrés Nascimento Belén Pérez-Dueñas Aida Ormazabal Rafael Artuch 《Analytical and bioanalytical chemistry》2014,406(18):4337-4343
The most widely used method for the biochemical screening of oligosaccharidoses is the analysis of the urinary oligosaccharide pattern by thin-layer chromatography on silica gel plates. However, this method is not always sensitive enough, and it is extremely time-consuming and laborious. In this work, the analysis of the urine oligosaccharide pattern was standardized for the first time by using capillary electrophoresis with laser-induced fluorescence (CE-LIF) detection (Beckman P/ACE MDQ) with a 488-nm argon ion laser module. All of the analyses were conducted using the Carbohydrate Labeling and Analysis Kit (Beckman-Coulter), which derivatizes samples with 8-aminopyrene-1,3,6-trisulfonate. Urine samples from 40 control subjects (age range, 1 week to 16 years) and from ten patients diagnosed with eight different lysosomal diseases (six of them included in the Educational Oligosaccharide Kit from ERNDIM EQA schemes) were analyzed. Two oligosaccharide excretion patterns were established in our control population according to age (younger or older than 1 year of age). Abnormal peaks with slower migration times than the tetrasaccharide position were observed for fucosidosis, α-mannosidosis, GM1 gangliosidosis, GM2 gangliosidosis variant 0, Pompe disease, and glycogen storage disease type 3. In conclusion, the first CE-LIF method to screen for oligosaccharidoses and related diseases, which also present oligosacchariduria, has been standardized. In all of the cases, the urine oligosaccharide analysis was strongly informative and showed abnormal patterns that were not present in any of the urine samples from the control subjects. Only urine from patients with aspartylglucosaminuria and Schindler disease displayed normal results. Figure
? 相似文献
154.
The shielding problems that arise due to the irregular penetrations such as neutral beam injection ducts should be treated carefully to aid in the shield design. The present work was undertaken to describe the effects arising due to radiation streaming through the neutral beam injector ducts (NBID) on the angular distribution of the total gamma ray doses at the outer surface of illmenite concrete shield (? = 4.6g/cm3). The shield is pierced with NBID of different diameters and lengths. The measurements were performed using a collimated beam of both gamma rays and neutrons emitted from one of the horizontal channels of the ET-RR-1 reactor. The measurements were carried out using 7LiF teflon thermoliminescent dosimeters. Generally the obtained data reveal that the presence of the total dose increase at the centerline of NBID and which in turn tends to decrease with the increase of scattered angle. An empirical formula describing the differential dose rate ratio is predicted. The experimental data obtained reveal good agreement with the calculated ones. 相似文献
155.
The characteristics of the thiol—disulphide exchange reaction are examined by an ab initio MO method. It is shown that this exchange reaction proceeds via one transition state, with almost no conformational distortion. 相似文献
156.
157.
T. Aida 《Journal of sound and vibration》1983,86(2):265-277
It is found that the perturbation equation of motion of a thin walled beam under a traveling follower load system becomes Hill's equation and that parametrically excited unstable coupled vibration occurs. The boundary frequency equations of the simple parametric resonance, from which the unstable regions are estimated, are obtained by Bolotin's method. Stability maps of a simply supported beam are shown, with account taken of the effects of load mass and damping. 相似文献
158.
A chirality-memorizing saddle-shaped porphyrin (12H) with 3,5-dipyridylphenyl side arms at the opposite meso positions underwent supramolecular polymerization in CH2Cl2 with a chiral Pd(II) complex of 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (PdII(BINAP)), forming a ladder-shaped polymer (32H) with a prevailing one-handed helical chirality. When this polymer was poured into AcOH containing 1,3-bis(diphenylphosphino)propane (DPPP) as a decomplexing agent, 32H was depolymerized in a stereochemically retentive way to give optically active 12H, hydrogen-bonded with AcOH. Although a cyclodimeric reference of 32H, formed from 22H having two 3-pyridylphenyl meso substituents in conjunction with PdII(BINAP), behaved similar to 32H, the translation efficiency of helical chirality was lower than that in the case with 32H. 相似文献
159.
Systematic studies on structural parameters for nanotubular assembly of hexa-peri-hexabenzocoronenes
Jin W Yamamoto Y Fukushima T Ishii N Kim J Kato K Takata M Aida T 《Journal of the American Chemical Society》2008,130(29):9434-9440
Thirteen different hexa-peri-hexabenzocoronenes (HBCs) I-III were newly synthesized, and their self-assembling behaviors were investigated. Taking into account also the reported behaviors of amphiphilic HBCs, some structural parameters of HBC essential for the tubular assembly were revealed. Points to highlight include (1) the importance of two phenyl groups attached to one side of the HBC unit, (2) essential roles of long paraffinic side chains on the other side of the phenyl groups, and (3) no necessity of hydrophilic oligo(ethylene glycol) side chains. The hierarchical nanotubular structure, rendered by virtue of a synchrotron radiation technique, was virtually identical to our previous proposal, where the nanotubes are composed of helically coiled bilayer tapes with a tilting angle of approximately 45 degrees. Each tape consists of pi-stacked HBC units, where the inner and outer HBC layers are connected by interdigitation of paraffinic side chains. The coiled structure is most likely caused by a steric congestion of the phenyl groups attached to the HBC unit, whose tilting direction may determine the handedness of the helically chiral nanotube. 相似文献
160.