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Bis(phthalocyaninato)yttrium Grown on Au(111): Electronic Structure of a Single Molecule and the Stability of Two- dimensional Films Investigated by Scanning Tunneling Microscopy/Spectroscopy at 4.8 K

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Nano Research 2010年第8期3卷 604-611页

作者： Yanfeng Zhang Pengfei Guan Hironari Isshiki Mingwei Chen masahiro yamashita Tadahiro Komeda Institute of Multidisciplinary Research for Advanced Materials Tohoku UniversitySendai 980-0877Japan Center for Nanochemistry Academy for Advanced Interdisciplinary StudiesDepartment of Advanced Materials and NanotechnologyCollege of EngineeringBeijing UniversityBeijing 100871China WPI-Advanced Institute for Materials Research Tohoku UniversitySendai 980-8577Japan Department of Chemistry Graduate School of ScienceTohoku UniversitySendai 980-8578Japan CREST Japan Science and Technology Agency(JST)Saitama 332-0012Japan

Scanning tunneling microscopy/spectroscopy(STM/STS)at 4.8 K has been used to examine the growth of a double-decker bis(phthalocyaninato)yttrium(YP_(c2))molecule on a reconstructed Au(111)*** differential conductance spectra(dI/dV)of a single YPc2 molecule allow the characteristics of the highest occupied molecular orbital(HOMO)and the lowest unoccupied molecular orbital(LUMO)to be ***,lateral distributions of the local density of states(LDOS)have also been obtained by dI/dV mapping and confirmed by first principles *** electronic feature mappings and theoretical calculations provide a basis for understanding the unique STM morphology of YPc2,which is usually imaged as an eight-lobed *** addition,we demonstrate that bias-dependent STM morphologies and simultaneous dI/dV maps can provide a way of understanding the stability of two-dimensional YP_(c2) films.

关键词： Scanning tunneling microscopy/spectroscopy(STM/STS) phthalocyanine electronic structure

Magnetic relaxation behavior of a spatially closed dysprosium(Ⅲ) phthalocyaninato double-decker complex

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Science China Chemistry 2012年第6期55卷 918-925,1178-1184页

作者： KATOH Keiichi UMETSU Kaori BREEDLOVE BRIAN K. yamashita masahiro Department of Chemistry Graduate School of Science Tohoku University 6-3 Aramaki-Aza-Aoba Aoba-ku Sendai Miyagi 980-8578 Japan

The SMM properties of the spatially closed Dy（Ⅲ） double-decker Pc complex Dy（obPc）2 （1）, which is equivalent to a pseudo dinuclear complex, are reported. Complex 1 crystallized with ethanol in the crystal lattice in the monoclinic space group P22/n and was isomorphous with Tb（obPc）2 （3）, which is arranged in a dimer structure along the b axis. The intermetallic Dy-Dy distance was determined to be 0.756 nm. ZMT versus T plots for 1 decreased with a decrease in T, which suggests the existence of an antiferromagnetic （AF） interaction between the Dy3＋ ions. The M-H curve for 1 at 1.8 K showed magnetic hysteresis. In ac susceptibility measurements on a powder sample of 1, which were dependent on the applied ac field, indicating that 1 is an single molecule magnet （SMM）, a maximum appeared at 22 K at an ac frequency 09 of 1488 Hz. The shape of the peaks dras- tically changed, and the peaks did not shift when an Hd~ large enough to suppress the quantum tunneling of the magnetization （QTM） was applied. The energy barrier （A/hc） was estimated to be 44 cm-1 with a pre-exponential factor （r0） of 1.6 × 10-5 s from an Arrhenius plot. Our results suggest that the SMM/magnetic properties of 1 significantly change in a dc magnetic field. These relaxation mechanisms are related to the energy gap of the ground state and to QTM.

关键词： single-molecule magnets dysprosium double-decker complex pseudo dinuclear complex magnetic relaxation process

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Magnetic relaxation behavior of a spatially closed dysprosium（Ⅲ） phthalocyaninato double-decker complex

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中国科学：化学 2012年第6期42卷 889-890页

作者： Keiichi KATOH Kaori UMETSU BRIAN K. BREEDLOVE masahiro yamashita Department of Chemistry Graduate School of Science Tohoku University 6-3 Aramaki-Aza-Aoba Aoba-ku Sendai Miyagi 980-8578 Japan

The SMM properties of the spatially closed Dy(Ⅲ) double-decker Pc complex Dy(obPc)2(1), which is equivalent to a pseudo dinuclear complex, are reported. Complex 1 crystallized with ethanol in the crystal lattice in the monoclinic space group P21/n and was isomorphous with Tb(obPc)2 (3), which is arranged in a dimer structure along the b axis. The intermetallic Dy-Dy distance was determined to be 0.756 nm. χMT versus T plots for 1 decreased with a decrease in T, which suggests the existence of an antiferromagnetic (AF) interaction between the Dy3+ions. The M-H curve for 1 at 1.8 K showed magnetic hysteresis. In ac susceptibility measurements on a powder sample of 1, which were dependent on the applied ac field, indicating that 1 is an single molecule magnet (SMM), a maximum appeared at 22 K at an ac frequency (f) of 1488 Hz. The shape of the peaks drastically changed, and the peaks did not shift when an Hdclarge enough to suppress the quantum tunneling of the magnetization (QTM) was applied. The energy barrier (Δ/ηχ) was estimated to be 44 cm-1with a pre-exponential factor (τt0) of 1.6 × 10-5s from an Arrhenius plot. Our results suggest that the SMM/magnetic properties of 1 significantly change in a dc magnetic field. These relaxation mechanisms are related to the energy gap of the ground state and to QTM.

关键词：镝(Ⅲ) 空间群弛豫行为封闭磁化率测量酞菁交流电场单分子磁体

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Dual-radical-based molecular anisotropy and synergy effect of semi-conductivity and valence tautomerization in a photoswitchable coordination polymer

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National Science Review 2023年第6期10卷 200-214页

作者： Jing-Wei Dai Yu-Qin Li Zhao-Yang Li Hai-Tao Zhang Carmen Herrmann Shohei Kumagai Marko Damjanovi? Markus Enders Hiroyuki Nojiri Masakazu Morimoto Norihisa Hoshino Tomoyuki Akutagawa masahiro yamashita State Key Laboratory of Medicinal Chemical Biology Nankai University School of Materials Science and Engineering Nankai University Institute of Inorganic and Applied Chemistry University of Hamburg Department of Chemistry Graduate School of Science Tohoku University Institute of Inorganic Chemistry University of Heidelberg Institute for Materials Research Tohoku University Department of Chemistry Rikkyo University Institute of Multidisciplinary Research for Advanced Materials (IMRAM) Tohoku University

Organic radicals are widely used as linkers or ligands to synthesize molecular magnetic ***,studies regarding the molecular anisotropies of radical-based magnetic materials and their multifunctionalities are ***,a photoisomerizable diarylethene ligand was used to form{[CoⅢ(3,5-DTSQ·-)(3,5-DTCat2-)]2(6F-DAE-py2)}·3CH3CN·H2O(o-1·3CH3CN·H2O,6F-DAE-py2=1,2-bis(2-methyl-5-(4-pyridyl)-3-thienyl)perfluorocyclopentene),a valence-tautomeric(VT) coordination *** directly observed dual radicals for a single crystal using high-field/-frequency(～13.3 T and～360 GHz) electron paramagnetic resonance(EPR) spectroscopy along the c-axis,which was further confirmed by angle-dependent Q-band EPR ***,a conductive anomaly close to the VT transition temperature was observed only when probes were attached at the ab plane of the single crystal,indicative of synergy between valence tautomerism and *** anisotropy studies and density functional theory(DFT) calculations revealed that this synergy is due to electron transfer associated with valence *** study presents the first example of dual-radical-based molecular anisotropy and charge-transfer-induced conductive anisotropy in a photoswitchable coordination polymer.

关键词： valence tautomerization charge transfer photo switching diradical coordination polymer

氰基桥联的[Fe4ⅢNi2Ⅱ]六核单分子磁体

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氰基桥联的[Fe4ⅢNi2Ⅱ]六核单分子磁体

基于元胞自动化模型的三维雪花晶体近似模式的产生(英文)

中国化学会第29届学术年会

作者：李朝阳 Kim R.Dunbar masahiro yamashita Department of Chemistry School of ScienceTohoku University Department of Chemistry Texas A&M UniversityCollege Station

分子磁性材料是一类通过化学方法将自由基或顺磁离子及抗磁配体以自组装的方式组合而形成的分子水平的磁性化合物。在这其中,单分子磁体（Single-Molecule Magnets,SMMs）尤其引人注目1-2,SMMs是指在磁场下能被磁化,而当磁场撤去后仍能... 详细信息

分子磁性材料是一类通过化学方法将自由基或顺磁离子及抗磁配体以自组装的方式组合而形成的分子水平的磁性化合物。在这其中,单分子磁体（Single-Molecule Magnets,SMMs）尤其引人注目1-2,SMMs是指在磁场下能被磁化,而当磁场撤去后仍能保持磁性的单个分子。由于在信息存储方面具有潜在的广泛的应用前景,SMMs日益成为化学、材料物理等学科的研究热点。本文报道了一例氰基桥联的[FeⅢ4NiⅡ2]六核化合物,{[FeⅢ（Tp*）（CN）3]4[NiⅡ（tptz）]2}·MeOH·nH2O（1）,我们通过X射线单晶衍射确定了化合物的结构,如图1a所示,更重要的是我们通过测量化合物的磁性性质（图1b是化合物的直流磁化率对温度的曲线）,成功观测到了缓慢磁驰豫现象,通过对其能垒的计算,可以认定化合物1是一例单分子磁体。

关键词：氰基过渡金属簇合物单分子磁体

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山东大学学报（工学版） 2009年第1期39卷 102-105,117页

作者：李芳佳高尚策唐政石井雅博山下和也富山大学工学部

关于雪花生长过程的计算机模拟已经受到了广泛关注.其中,元胞自动化模型是一种基于网格和简单规则的计算方法.尽管这是一种简单的模型,但其在模拟复杂过程(比如:生命现象,晶体生长和湍流)时往往能取得较好的结果.提出了一种由传统的二... 详细信息

关于雪花生长过程的计算机模拟已经受到了广泛关注.其中,元胞自动化模型是一种基于网格和简单规则的计算方法.尽管这是一种简单的模型,但其在模拟复杂过程(比如:生命现象,晶体生长和湍流)时往往能取得较好的结果.提出了一种由传统的二维模型扩展而来的三维雪花晶体生长方法.计算机模拟结果显示提出的方法能够更精确地模拟出三维雪花的晶体化过程.

关键词：雪花晶体近似模式元胞自动化模型

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Effects of Short Time Variation in the River Discharge on the Salt Wedge Intrusion in the Yura Estuary, a Micro Tidal Estuary, Japan

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Journal of Water Resource and Protection 2013年第3期5卷 343-348页

作者： Tatsuhiro Funahashi Akihide Kasai masahiro Ueno Yoh yamashita Field Science Education and Research Center Kyoto University Maizuru Japan Graduate School of Agriculture Kyoto University Kyoto Japan

A numerical model was developed to investigate salinity distribution in the Yura Estuary, a micro tidal estuary in Japan. The model results show that the salinity distribution as represented by salt wedge intrusion agreed well with field observations. In addition to the seasonal variation, the salt wedge responds over short time scales according to the flood events. The retreat of the salt wedge is dependent on the scale of the river discharge;the salt wedge moved back and disappeared from the estuary when over250 m3·s-1 of fresh water was discharged from the estuary and it takes ~11 days for salt wedge to recover from the fresh water discharge event. The Yura Estuary has on average three floods during summer, this coincides with when phytoplankton is most productive in the river and indicates that the short temporal variations in the river discharge has important effects not only on the hydrodynamics, but also on the ecosystem in the estuary.

关键词： Micro Tidal Estuary River Discharge Salt Wedge Intrusion Short Time Variation

Recent evidence for subcutaneous drains to prevent surgical site infections after abdominal surgery:A systematic review and metaanalysis

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World Journal of Gastrointestinal Surgery 2023年第12期15卷 2879-2889页

作者： Tomohiro Ishinuki Hiroji Shinkawa Keita Kouzu Seiichi Shinji Erika Goda Toshio Ohyanagi masahiro Kobayashi Motomu Kobayashi Katsunori Suzuki Yuichi Kitagawa Chizuru yamashita Yasuhiko Mohri Junzo Shimizu Motoi Uchino Seiji Haji masahiro Yoshida Hiroki Ohge Toshihiko Mayumi Toru Mizuguchi Department of Nursing Surgical SciencesSapporo Medical UniversitySapporo 060-8556HokkaidoJapan Department of Hepatobiliary-Pancreatic Surgery Osaka Metropolitan University Graduate School of MedicineAbeno-Ku 545-0051Japan Department of Surgery National Defense Medical CollegeTokorozawa 359-8513Japan Department of Gastrointestinal and Hepato-Biliary-Pancreatic Surgery Nippon Medical SchoolTokyo 113-8602Japan Department of Nursing Japan Health Care UniversitySapporo 062-0053Japan Department of Liberal Arts and Sciences Center for Medical EducationSapporo Medical UniversitySapporo 060-8556Japan Department of Clinical Pharmacokinetics Research and Education Center for Clinical PharmacyKitasato UniversityTokyo 108-8641Japan Department of Anesthesiology Hokushinkai Megumino HospitalEniwa 061-1395Japan Department of Infectious Disease Medicine School of MedicineUniversity of Occupational and Environmental HealthKitakyushu 807-8555Japan Department of Gastrointestinal Surgery National Center for Geriatrics and GerontologyObu 474-8511Japan Department of Anesthesiology and Critical Care Medicine Fujita Health UniversityToyoake 470-1192Japan Department of Gastrointestinal Surgery Mie Prefectural General Medical CenterYokkaich 510-8561Japan Department of Surgery Toyonaka Municipal HospitalToyonaka 560-8565Japan Department of Gastroenterological Surgery Hyogo Medical UniversityNishinomiya 663-8501Japan Department of Surgery Soseikai General HospitalKyoto 612-8473Japan Department of Hepato-Biliary-Pancreatic&Gastrointestinal Surgery International University of Health and WelfareIchikawa 272-0827Japan Department of Infectious Disease Hiroshima University HospitalHiroshima 734-8551Japan Department of Intensive Care Unit Chukyo HospitalJapan Community Health Care OrganizationNagoya 457-8510Japan

BACKGROUND Surgical site infections(SSIs)increase mortality,hospital stays,additional medical treatment,and medical *** drains prevent SSIs in gynecological and breast surgeries;however,their clinical impact in abdominal surgery remains *** To investigate whether subcutaneous drains were beneficial in abdominal surgery using a systematic review and *** The database search used PubMed,MEDLINE,and the Cochrane *** following inclusion criteria were set for the systematic review:(1)Randomized controlled trial studies comparing SSIs after abdominal surgery with or without subcutaneous drains;and(2)Studies that described clinical outcomes,such as SSIs,seroma formation,the length of hospital stays,and *** Eight studies were included in this *** rate of total SSIs was significantly lower in the drained group(54/771,7.0%)than in the control group(89/759,11.7%),particularly in gastrointestinal ***,the rate of superficial SSIs was slightly lower in the drained group(31/517,6.0%)than in the control group(49/521,9.4%).No significant differences were observed in seroma formation between the *** stays were shorter in the drained group than in the control *** Subcutaneous drains after abdominal surgery prevented SSIs and reduced hospital stays but did not significantly affect seroma *** timing of drain removal needs to be reconsidered in future studies.

关键词： Abdominal surgery Mortality Seroma formation Subcutaneous drain Surgical site infections

Comparison of PPIs and H_2-receptor antagonists plus prokinetics for dysmotility-like dyspepsia

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World Journal of Gastroenterology 2012年第13期18卷 1517-1524页

作者： masahiro Sakaguchi Miyuki Takao Yasuo Ohyama Hiroshi Oka Hiroshi yamashita Takumi Fukuchi Kiyoshi Ashida masahiro Murotani Masuyo Murotani Kazuo Majima Hiroshi Morikawa Takashi Hashimoto Keisuke Kiyota Hirohiko Esaki Kanji Amemoto Gouhei Isowa Fumiyuki Takao Department of Gastroenterology Moriguchi Keijinkai HospitalMoriguchiOsaka 570-0021Japan Department of Gastroenterology Osaka Saiseikai Nakatsu HospitalOsaka 530-0012Japan Murotani Clinic KadomaOsaka 571-0008Japan Majima Clinic NeyagawaOsaka 572-0084Japan Morikawa Clinic HirakataOsaka 573-0058Japan Hashimoto Clinic MoriguchiOsaka 570-0079Japan Kiyota Clinic MatsubaraOsaka 580-0004Japan Department of Gastroenterology Arisawa General HospitalHirakataOsaka 573-1195Japan Amemoto Clinic MoriguchiOsaka 570-0021Japan Isowa Clinic NeyagawaOsaka 572-0062Japan Mii Clinic NeyagawaOsaka 572-0019Japan

AIM： To compare efficacy of proton pump inhibitors （PPIs） with H2-receptor antagonists （H2RA$） plus pro- kinetics （Proks） for dysmotility-like symptoms in func- tional dyspepsia （FD）. METHODS： Subjects were randomized to receive openlabel treatment with either rabeprazole 10 mg od （n = 57） or famotidine 10 mg bid plus mosapride 5 mg tid （n = 57） for 4 wk. The primary efficacy endpoint was change （%） from baseline in total dysmotility-like dyspepsia symptom score. The secondary efficacy endpoint was patient satisfaction with treatment. RESULTS： The improvement in dysmotility-like dyspep- sia symptom score on day 28 was significantly greater in the rabeprazole group （22.5% ± 29.2% of baseline） than the famotidine ＋ mosapride group （53.2%±58.6% of baseline, P 〈 0.0001）. The superior benefit of rabeprazole treatment after 28 d was consistent regardless of Helicobacter pylori status. Significantly more subjects in the rabeprazole group were satisfied or very satisfied with treatment on day 28 than in the famotidine ＋ mosapride group （87.7% vs 59.6%, P = 0.0012）. Rabeprazole therapy was the only significant predictor of treatment response （P 〈 0.0001）, defined as a total symptom score improvement ≥ 50%. CONCLUSION： PPI monotherapy improves dysmotil- ity-like symptoms significantly better than H2RAs plus Proks, and should be the treatment of first choice for Japanese FD.

关键词： Dysmotility Functional dyspepsia H2-recep-tor antagonist Prokinetics Proton pump inhibitor