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111.
Kohei Shimamura Fuyuki Shimojo Aiichiro Nakano Shigenori Tanaka 《Journal of computational chemistry》2019,40(2):349-359
Recent experiments concerning prebiotic materials syntheses suggest that the iron-bearing meteorite impacts on ocean during Late Heavy Bombardment provided abundant organic compounds associated with biomolecules such as amino acids and nucleobases. However, the molecular mechanism of a series of chemical reactions to produce such compounds is not well understood. In this study, we simulate the shock compression state of a meteorite impact for a model system composed of CO2, H2O, and metallic iron slab by ab initio molecular dynamics combined with multiscale shock technique, and clarify possible elementary reaction processes up to production of organic compounds. The reactions included not only pathways similar to the Fischer–Tropsch process known as an important hydrocarbon synthesis in many planetary processes but also those resulting in production of a carboxylic acid. It is also found that bicarbonate ions formed from CO2 and H2O participated in some forms in most of these observed elementary reaction processes. These findings would deepen the understanding of the full range of chemical reactions that could occur in the meteorite impact events. © 2018 Wiley Periodicals, Inc. 相似文献
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Shunji Nomura Hiromichi Kawai Itzuro Kimura Mitzuyasu Kagiyama 《Journal of Polymer Science.Polymer Physics》1967,5(3):479-491
The relationship between the optical anisotropy of high polymeric materials in bulk and the orientation of structural units within the materials was described in general by using several types of mean values of the orientation distribution function of three Eulerian angles, i.e., the orientation factors, under some assumptions about the symmetry of the function being applicable for the most of the industrial products. A newly defined biaxial orientation factor, Fθηi = 〈sin2 θj cos 2ηj〉, where θj and ηj are the polar and azimuthal angles of the jth axis within the structural unit with respect to the bulk axes, may relate the biaxial orientation of the structural units to the dichroic orientation factors, which are measurable optical anisotropic indices of the bulk materials. Some applications of the results to the birefringence and infrared and dye dichroism are also discussed. 相似文献
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Fujikawa S Muto E Kunitake T 《Langmuir : the ACS journal of surfaces and colloids》2007,23(8):4629-4633
We report herein the fabrication of ferritin-embedded self-supporting silica nanofilms via a simple spin-coating process. Ferritin was employed as a template molecule, and solutions of ferritin and silica were spread on a polymer-coated silicon substrate, in this order. After dissolving the polymer underlayer by simply immersing ethanol, a centimeter-sized self-supporting nanofilm of ferritin/silica composite with a thickness of 15 nm was successfully transferred onto an alumina membrane without the film breaking. Ozone and hydrochloric acid solution treatment removed the template ferritin molecules from the composite film to produce corresponding transmembrane nanoholes. The reported method is very simple, and the fabrication of a protein-embedded self-supporting nanofilm enables the design of biomembrane-mimetic devices. 相似文献
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Kodai KINOSHITA Kazushi KIMURA Shigenori MIYAMOTO Yuichi TAKATA Yuji KODAMA Akira IEIRI Kazuhiro ISHIDA Masahiro INOUE Satomi ABE Takashi MIKAMI Taiki KANNO 《Physical Therapy Research》2021,24(3):232
Objective: Preoperative factors related to perceived leg length discrepancy (PLLD) after total hip arthroplasty (THA) are not well studied. This study aimed to examine the preoperative factors, including hip abductor modulus, related to PLLD one month after THA. Methods: The study included 73 patients diagnosed with osteoarthritis secondary to developmental dysplasia of the hip and a posterior approach to surgery. Multiple logistic regression analysis was performed using the presence or absence of PLLD as the dependent variable and preoperative hip abductor''s modulus of elasticity, pain, hip abduction range of motion, hip abductor muscle strength and pelvic obliquity as the independent variable. Additionally, receiver operating characteristic curves were used for the extracted variables for calculating the cutoffs, sensitivity, specificity and area under the curve (AUC) to determine the presence or absence of PLLD. The significance level was set at p<0.05. Results: The hip abductor modulus (odds ratio=1.13; 95% confidence interval=1.06-1.21; p<0.001) was selected as a preoperative factor. The cutoff value to determine the presence or absence of a PLLD was 16.32 kPa. The sensitivity and specificity were 81.8% and 72.5%, respectively, and the AUC was 0.8137. Conclusion: The hip abductor muscle elastic modulus affected PLLD one month after THA. If the preoperative hip abductor elastic modulus is higher than the cutoff value, it may affect the appearance of PLLD at one month postoperatively. 相似文献
120.
In Situ Synthesis of Robust Conductive Cellulose/Polypyrrole Composite Aerogels and Their Potential Application in Nerve Regeneration 下载免费PDF全文
Zhuqun Shi Huichang Gao Jiao Feng Beibei Ding Prof. Xiaodong Cao Prof. Shigenori Kuga Prof. Yingjun Wang Prof. Lina Zhang Prof. Jie Cai 《Angewandte Chemie (International ed. in English)》2014,53(21):5380-5384
Nanostructured conductive polymers can offer analogous environments for extracellular matrix and induce cellular responses by electric stimulation, however, such materials often lack mechanical strength and tend to collapse under small stresses. We prepared electrically conductive nanoporous materials by coating nanoporous cellulose gels (NCG) with polypyrrole (PPy) nanoparticles, which were synthesized in situ from pyrrole monomers supplied as vapor. The resulting NCG/PPy composite hydrogels were converted to aerogels by drying with supercritical CO2, giving a density of 0.41–0.53 g cm?3, nitrogen adsorption surface areas of 264–303 m2 g?1, and high mechanical strength. The NCG/PPy composite hydrogels exhibited an electrical conductivity of up to 0.08 S cm?1. In vitro studies showed that the incorporation of PPy into an NCG enhances the adhesion and proliferation of PC12 cells. Electrical stimulation demonstrated that PC12 cells attached and extended longer neurites when cultured on NCG/PPy composite gels with DBSA dopant. These materials are promising candidates for applications in nerve regeneration, carbon capture, catalyst supports, and many others. 相似文献