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排序方式: 共有713条查询结果,搜索用时 15 毫秒
51.
52.
Itaru Natori Shizue Natori Anna Kanasashi Kosuke Tsuchiya Kenji Ogino 《Reactive and Functional Polymers》2013,73(1):200-206
The synthesis of tetraphenylporphyrin (H2TPP)-end-functionalized poly(p-phenylene) (H2TPP-PPP) as a leaf-green-colored soluble semiconducting polymer with a well-controlled and defined polymer chain structure was achieved for the first time. Chloromethyl-end-functionalized poly(1,3-cyclohexadiene) (CM-PCHD) was prepared by the living anionic polymerization of 1,3-cyclohexadiene and the post-polymerization reaction of poly(1,3-cyclohexadienyl)lithium and chloro(chloromethyl)dimethylsilane. H2TPP-end-functionalized PCHD (H2TPP-PCHD) was then prepared by the addition of 5-(4-hydroxyphenyl)-10,15,20-triphenylporphyrin to CM-PCHD. The dehydrogenation of H2TPP-PCHD with 2,3-dichloro-5,6-dicyano-1,4-benzoquinone was performed under ultrasonic irradiation, and H2TPP-PPP was obtained as a target polymer in almost quantitative yield. The –Si(CH3)2–CH2–O– bond in H2TPP-PPP effectively inhibited the coordination of the H2TPP end-group onto the PPP moiety, and the aggregation of H2TPP-PPP with the accumulation of the H2TPP end-group was formed. H2TPP-PPP exhibited a leaf-green color and had a very broad absorption band overlapping the visible-light region, similar to chlorophyll a. 相似文献
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54.
This study measured air exchange rates, indoor concentrations of aldehydes and volatile organic compounds (VOCs), and radioactivity levels at 19 temporary houses in different temporary housing estate constructed in Minamisoma City following the Great East Japan Earthquake. The 19 surveyed houses represented all of the companies assigned to construct temporary houses in that Minamisoma City. Data were collected shortly after construction and before occupation, from August 2011 to January 2012. Mean air exchange rates in the temporary houses were 0.28/h, with no variation according to housing types and construction date. Mean indoor concentrations of formaldehyde, acetaldehyde, toluene, ethylbenzene, m/p‐xylene, o‐xylene, styrene, p‐dichlorobenzene, tetradecane, and total VOCs (TVOCs) were 29.2, 72.7, 14.6, 6.35, 3.05, 1.81, 7.29, 14.3, 8.32, and 901 μg/m3, respectively. The levels of acetaldehyde and TVOCs exceeded the indoor guideline (48 μg/m3) and interim target (400 μg/m3) in more than half of the 31 rooms tested. In addition to guideline chemicals, terpenes (α‐pinene and d‐limonene) and acetic esters (butyl acetate and ethyl acetate) were often detected in these houses. The indoor radiation levels measured by a Geiger–Müller tube (Mean: 0.22 μSv/h) were lower than those recorded outdoors (Mean: 0.42 μSv/h), although the shielding effect of the houses was less than for other types of buildings. 相似文献
55.
A detailed procedure of full-electromagnetic Vlasov simulation technique is presented. Our new unsplitting conservative scheme exactly satisfies the continuity equation for charge. The implicit Finite Difference Time Domain method is also adopted for computation of electromagnetic fields, which is not restricted by the CFL condition for light. The Geospace Environment Modeling magnetic reconnection challenge problem is adopted as a benchmark test. The characteristics of the present Vlasov code are studied by varying the resolution in configuration space. 相似文献
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C Ogino Y Negi T Matsumiya K Nakaoka A Kondo S Kuroda S Tokuyama U Kikkawa T Yamane H Fukuda 《Canadian Metallurgical Quarterly》1999,125(2):263-269
Phospholipase D (PLD), secreted into the culture medium of an actinomycete, Streptoverticillium cinnamoneum, has been purified to homogeneity and characterized. The Stv. cinnamoneum PLD efficiently catalyzes both the hydrolysis and transphosphatidylation of various phospholipids, including phosphatidylethanolamine (PE), phosphatidylcholine (PC), and phosphatidylserine (PS). However, the substrate specificity differs between the two reactions; PE serves as the most preferred substrate for the hydrolysis, but PC and PS are better substrates than PE for the transphosphatidylation. In addition, the transphosphatidylation but not the hydrolysis of PE and PC is markedly activated on the addition of metal ions, especially Al3+. Nucleotide and amino acid sequence determination of the Stv. cinnamoneum PLD revealed the presence of common structural motifs identified in all PLD sequences from various species. 相似文献
58.
Some experiments on the scratching of silicon:: In situ scratching inside an SEM and scratching under high external hydrostatic pressures 总被引:1,自引:0,他引:1
M. Yoshino T. Aoki T. Shirakashi R. Komanduri 《International Journal of Mechanical Sciences》2001,43(2):335
To elucidate the mechanisms of material removal in ultra precision machining of silicon involving deformation and fracture, in situ scratching of silicon with a diamond stylus inside a scanning electron microscope (SEM) using a specially designed tribometer and scratching under zero and high (400 MPa) external hydrostatic pressures using a specially designed high-pressure machining apparatus were conducted. The resulting scratches were examined in an SEM to evaluate the influence of depth of cut and hydrostatic pressure on the nature of scratches produced (smooth versus fractured surfaces) and the possible brittle–ductile transition. Experimental results indicate that hydrostatic pressure plays an important role in minimizing fracture and producing smooth surfaces. Reasonable agreement of the experimental results with the meso-plasticity FEM simulation of indentation was obtained. 相似文献
59.
H Ohtsuka T Higuchi H Matsuzawa H Sato K Takahashi J Takahashi TO Yoshino 《Canadian Metallurgical Quarterly》1997,59(11):1075-1077
The inhibitory effect of chlorpromazine (CPZ), pentoxifylline (PTX) and dexamethasone (DEX) was investigated in a model of endotoxin shock in Holstein calves following an intravenous administration of Esherichia coli endotoxin (LPS). Initial correlations with its effects on the levels of tumor necrosis factor (TNF), a pivotal mediator of endotoxin shock, and clinical signs were obtained. The pretreatment of CPZ or DEX significantly decreased the serum levels of TNF, and reduced endotoxic shock. But the pretreatment of PTX hardly reduced the increase of serum TNF levels and endotoxin shock. The levels of serum endotoxin were not significantly different a minute of postinjection of LPS in calves. The results of this study indicate that pretreatment of CPZ or DEX inhibit various biological effects on endotoxin in calves. 相似文献
60.
Xiaodong Wang Ogino K. Tanaka K. Usui H. 《IEEE journal of selected topics in quantum electronics》2004,10(1):121-126
A novel iridium complex having the polymerizable functional group as one of the ligands, bis(2-phenylene pyridine) acrylate iridium lr(ppy)2Ac was synthesized as a phosphorescent dopant for electroluminescent (EL) devices. It has a photoluminescence spectrum peak at about 530 nm. EL devices were fabricated by doping lr(ppy)2Ac into host materials, such as BCP (2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline) and poly(N-vinyl carbazole) (PVCz). Bright blue-green luminescence of about 12 000 cd/m2 was observed for an EL device having a structure of indium-tin oxide JTO)/1r(ppy)2Ac-doped TPD:PVCz/BCP/Alq3 [tris(8-hdroxyquinoline) aluniinuml/Mg:Ag. Furthermore, the iridium complex was copolymerized with N-vinyl carbazole (VCz) to form a random copolymer with a number average molecular weight of about 1000. An EL device using this hole-transport layer gave bright blue-green emission of more than 6000 cd/m2. These results indicate that lr(ppy)2Ae, especially its copolymer with VCz, can be a promising phosphorescent material for organic EL devices. 相似文献