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91.
Yuki Kataoka Naoya Kanbayashi Naoka Fujii Taka‐aki Okamura Takeharu Haino Kiyotaka Onitsuka 《Angewandte Chemie (International ed. in English)》2020,59(26):10286-10291
π‐Stacked polymers, which consist of layered π‐electron systems in a polymer, can be expected to be used in molecular electronic devices. However, the construction of a stable π‐stacked structure in a polymer is considerably challenging because it requires sophisticated designs and precise synthetic methods. Herein, we present a novel π‐stacked architecture based on poly(quinolylene‐2,3‐methylene) bearing alanine derivatives as the side chain, obtained through the living cyclo‐copolymerization of an o‐allenylaryl isocyanide. In the resulting polymer, the neighboring quinoline rings of the main chain form a layered structure with π–π interactions, which is stabilized by intramolecular hydrogen bonds. The vicinal quinoline units form two independent helices and the whole molecule is a twisted‐tape structure. This structure is established on the basis of UV/CD spectra, theoretical calculations, and atomic‐force microscopy. 相似文献
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Miyauchi Suguru Yamada Shuji Takeuchi Shintaro Tazaki Asahi Kajishima Takeo 《Transport in Porous Media》2022,141(1):185-199
Transport in Porous Media - A concise and accurate prediction method is required for membrane permeability in chemical engineering and biological fields. As a preliminary study on this topic, we... 相似文献
94.
Takura SASAKI Junichiroh KANEKO Masahiro ISHIZAKA Naoya SUZUKI Syuichiro KIMURA 《Physical Therapy Research》2021,24(3):249
Objective: This study aimed to clarify the effects of pre- and postoperative physical function on the 6-minute walking distance (6MWD) in patients with peripheral arterial disease (PAD). Method: Forty-two elderly patients with PAD who were hospitalized for revascularization and able to walk independently were included in the study. The 6MWD, ankle brachial index (ABI), weight-bearing index (WBI), gait, and intermittent claudication distance (ICD) were measured before and after the surgery, and skeletal muscle index was measured only before surgery. Analyses were performed by comparing the pre- and postoperative values of each factor using a paired t-test. In addition, multiple regression analysis was performed with 6MWD as the dependent variable before and after surgery. Results: Postoperatively, pain disappeared in 22 patients, and ABI, ICD, 6MWD, and stride length improved significantly. ICD and stride length were extracted as factors related to 6MWD before and after surgery, and ABI, WBI, and stride length were extracted as factors related to 6MWD after surgery. Conclusion: The improvement of intermittent claudication associated with revascularization suggests a stronger influence of functional aspects on postoperative 6MWD. 相似文献
95.
Naoya Onishi Ryoichi Kanega Hajime Kawanami Yuichiro Himeda 《Molecules (Basel, Switzerland)》2022,27(2)
Recently, there has been a strong demand for technologies that use hydrogen as an energy carrier, instead of fossil fuels. Hence, new and effective hydrogen storage technologies are attracting increasing attention. Formic acid (FA) is considered an effective liquid chemical for hydrogen storage because it is easier to handle than solid or gaseous materials. This review presents recent advances in research into the development of homogeneous catalysts, primarily focusing on hydrogen generation by FA dehydrogenation. Notably, this review will aid in the development of useful catalysts, thereby accelerating the transition to a hydrogen-based society. 相似文献
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In this paper, we investigate a delayed HIV infection model that considers the homeostatic proliferation of CD4+ T cells. The existence and stability of uninfected equilibrium and infected equilibria(smaller and larger ones) are studied by analyzing the characteristic equation of the system. The intracellular delay does not affect the stability of uninfected equilibrium, but it can change the stability of larger positive equilibrium and Hopf bifurcation appears inducing stable limit c... 相似文献
100.