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Bulking Up the Bay-Position Substituents Enables Enhanced Selectivity of C_(s)‑Symmetric Boron Subphthalocyanine−Subnaphthalocyanine Hybrids

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Precision Chemistry 2024年第4期2卷 161-181页

作者： Nina F.Farac Alan j.Lough timothy P.Bender Department of Chemical Engineering and Applied Chemistry University of TorontoTorontoOntario M5S 3E5Canada Department of Chemistry University of TorontoTorontoOntario M5S 3H6Canada Department of Materials Science and Engineering University of TorontoTorontoOntario M5S 3E4Canada Department of Mechanical and Industrial Engineering University of TorontoTorontoOntario M5S 3G8Canada

the precise synthesis of subporphyrinoid hybrids withπ-expanded topologies and unique material properties plays a promising role in the design of functional ***,selective,and controllable routes to boron subphthalocyanine−subnaphthalocyanine hybrids,Bsub(Pc_(3‑p)-Nc_(p))s,are desirable for this purpose yet synthetically challenging due to random mixtures of C_(s-),C_(3v-),and,in some cases,C_(1)-symmetric compounds that form during traditional statistical mixed ***,we addressed this issue by developing a sterically driven mixed cyclotrimerization with enhanced selectivity for the targeted C_(s)-symmetric hybrid and complete suppression of sterically crowded macrocyclic *** process,coupled with a rationally designed precursor bearing bulky phenyl substituents,enabled the synthesis and characterization of bay-position phenylated Ph_(2)-(R_(p))_(8)Bsub(Pc_(2)-Nc_(1))hybrids with halogens(Rp=Cl or F)in their peripheral isoindole *** selectivity ranged between 59 and 72%with remarkable yields,significantly higher than that of conventional mixed *** findings were augmented by theoretical calculations on precursor Lewis basicity as guiding principles into hybrid macrocycle ***,the incorporation of unfused phenyl groups and halogen atoms into the hybrid framework resulted in fine-tuned optical,structural,electronic,and electrochemical *** straightforward approach achieved improved selectivity and controlled narrowing of the product distribution,affording the efficient synthesis of structurally sophisticated Bsub(Pc_(2)-Nc_(1))*** then expands the library of 3-dimensionalπ-extended macrocycles for use in a range of applications,such as in optoelectronic devices with precisely tailored optical properties.

关键词： subphthalocyanine hybrids low-symmetry aromatic macrocycle selective cyclotrimerization sterically driven chemistry broad absorption material properties

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中国某些铁陨石的化学分类

地球化学 1983年第2期12卷 109-120页

作者：王道德 D.j.麦尔文 j.t.沃森中国科学院地球化学研究所美国洛杉矶加利福尼亚大学地球物理和行星物理研究所

Based on structural observations and the concentrations of Cr, Co, Ni, Cu, Ga, Ge,As, Sb， Re, Ir and Au by neutron-activation analysis we have classified 14 Chinese iron meteorites. thirteen are members of the large groups IAB, IIICD, IIICD,IIIAB and *** is an ungrouped iron meteorite that falls within the IIE field on some elementNi diagrams, but is distinctly outside this .fiel on plots of Cu, W, and Ir vs. Ni; it is very similar in Composition to techado,another ungrouped iron. the high Cu content of Leshan is consistent with other evidence indicating that Cu is a valuable parameter for classifying, iron meteorites. IIICD Dongling appears not to be a new meteorite, but to be paired with Nantan; Dongling was recovered about 50 km from the location of the Nantan shower. Yungning is highly oxidized; we assign it to group LAB but cannot rule out IIICD. IVA-An Longchang has many characteristics of IVA irons, but has been remelted, prebably in a terrestrial setting, Five irons belong to group IVA, a remarkably large number. three are identical in Composition, and we suspect that the two from Hubei, Guanghua and Huangling, are paired. thus this set of 14 irons ineludes 12 independent fall.

关键词：铁陨石元素丰度地球化学中国

Performance and Internal Flow of Sirocco Fan Using Contra-Rotating Rotors

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journal of thermal Science 2008年第1期17卷 35-41页

作者： j.Fukutomi t.Shigemitsu t.Yasunobu Institute of Science and technology The University of Tokushima2-1 Minamijyosanjima-choTokushima 770-8506JAPAN Institute of Science and technology The University of Tokushima2-1 Minamijyosanjima-choTokushima 770-8506JAPAN Research Associate Graduate School of Advanced technology and Science The University of Tokushima2-1 Minamijyosanjima-choTokushima 770-8506JAPAN

A sirocco fan using contra-rotating rotors in which an inner rotor is settled inside the sirocco fan rotor and each rotor rotates in an opposite direction was proposed for the purpose of getting the higher pressure and making the structure of a sirocco fan more compact. If the high discharge pressure is obtained with the adoption of the contra-rotating rotors, it could be used for various purposes. Pressure coefficient of a sirocco fan with contra-rotating rotors is 2.5 times as high as the conventional sirocco fan and the maximum efficiency point of contra-rotating rotors shifts to larger flow rate than a conventional sirocco fan. On the other hand, it was clarified from the flow measurement results that circumferential velocity component at the outlet of the outer rotor of contra-rotating ro- tors becomes larger than a conventional one. In the present paper, the performance of a conventional sirocco fan and a sirocco fan with contra-rotating rotors are shown and the internal flow field at the outlet of outer rotor of both cases is clarified. then, the effect of different kind of contra-rotating rotors on the performance and internal flow field is investigated and the rotor design with higher performance would be discussed.

关键词： Sirocco fan High pressure Contra-rotating rotors Slow angle Circular arc blade Aerofoil blade

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历史上的身体

Stochastic framework for modeling the linear apparent behavior of complex materials:Application to random porous materials with interphases

作者： (英)约翰·罗布(john Robb) (英)奥利弗·j.t. 哈里斯(Oliver j.t. Harris)

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Acta Mechanica Sinica 2013年第6期29卷 773-782页

作者： j.Guilleminot t.t.Le C.Soize Universit Paris-Est Laboratoire Modlisation et Simulation Multi EchelleMSME UMR8208 CNRS5 Bd Descartes77454 Marne la ValleFrance

this paper is concerned with the modeling of randomness in multiscale analysis of heterogeneous materials. More specifically, a framework dedicated to the stochastic modeling of random properties is first introduced. A probabilistic model for matrix-valued second-order random fields with symmetry propertries, recently proposed in the literature, is further reviewed. Algorithms adapted to the Monte Carlo simulation of the proposed representation are also provided. the derivations and calibration procedure are finally exemplified through the modeling of the apparent properties associated with an elastic porous microstructure containing stochastic interphases.

关键词： Apparent properties MaxEnt Probabilistic model

two-fluid modelling for cylindrical fluidized beds using kinetic theory for rough spheres

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Particuology 2020年第3期18卷 25-34页

作者： Lei Yang j.t.Padding j.A.M.Kuipers Helmholtz Institute Erlangen-Nürnberg for Renewable Energy(IEK-11) Fürther Straβe 24890429 NurnbergGermany Department of Process and Energy Delft University of Technology2628CB DelftThe Netherlands Department of Chemical Engineering and Chemistry Eindhoven University of Technology5600MB EindhovenThe Netherlands

Recently,we have extended the kinetic theory of granular flow (KtGF) to include friction between the spherical particles and tested it in rectangular *** this study,the extended KtGF implemented in cylindrical coordinates is used to model the more-commonly employed cylindrical bubbling fluidized *** attention is paid to the anti-symmetric part of the velocity gradient in the solids stress *** verification of the implementation,a comparison of the present model in the limit of zero friction with the original (frictionless) KtGF model was ***,simulations of bubbling fluidized beds of inelastic particles were performed using our extended KtGF and an effective KtGF model for inelastic particles of jenkins and *** simulation results show good agreement for the time-averaged solids volume fraction distribution and solids circulation ***,our model is validated by predicting the individual bubble behavior in dense bubbling fluidized beds containing different granular materials in a comparison with experimental data from Verma et al.(2014).the extended KtGF leads to an improved agreement with experimental bubble *** to previous work (Yang et al.,2016b,2017c),and by introducing cylindrical coordinates,the current work demonstrates that the extended KtGF improves predictions for the temporal bubble behavior of cylindrical fluidized beds.

关键词： Fluidization Frictional collision Rough particles Cylindrical bed hydrodynamics two-fluid model

HIGH StRAIN RAtE SUPERPLAStICItY OF A AIN PARtICULAtE REINFORCED 6061Al COMPOSItE

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Acta Metallurgica Sinica(English Letters) 2001年第2期14卷 127-131页

作者： L.H. Han, j.t. Niu and D.M. jiang (the National Key Laboratory of Advanced Welding Production technology, Harbin Institute of technology,Harbin 150001, China) t. Imai (National Industrial Research Institute of Nagoya, 1 Hirate-cho, Kita-ku, Nagoya 462, ja Harbin Inst. of technol. Harbin 150001 China

the superplasticity of AINp/6061Al composite, fabricated by powder metallurgy method and hot-rolled after extrusion, was investigated. the AINp/6061Al composite exhibits an m-value of 0.49 and a maximum elongation of 438% in the strain rates ranging hem 10-2-100s-1 and at temperatures from 823K to 893K. Diffirential scanning calorimeter was used to ascertain the possibility of any partial melting in the vicinity of optimum superplastic temperature. these results suggested that liquid phase existed where maximum elongation was obtained.

关键词： superplasticity aluminum matrix composite AIN particulate

Microstructure and tensile properties of magnesium nanocomposites fabricated using magnesium chips and carbon black

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journal of Magnesium and Alloys 2020年第3期8卷 860-872页

作者： t.j.Lee W.j.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

In this study,carbon black(0,0.01,0.03 and 0.08 wt%)and AZ31(Mg-3Al-lZn)magnesium chips were used to fabricate carbon black-reinforced magnesium matrix composites with extrusion or a combination of extrusion and high-ratio differential speed *** hot pressing at 693 K and extrusion at 623 K with an extrusion ratio of 22,the magnesium chips coated with carbon black were soundly bonded into a bulk composite *** grain sizes of the extruded materials were similar with a size of 48.2-51.5|im despite the difference in the amount of carbon *** yield strength and ultimate tensile strength increased from 177 to 191 MPa and from 240 to 265 MPa,respectively,as a result of the addition of 0.01%carbon black;however,a further increase in the strength was marginal with additional carbon *** same trend was observed in the strain hardening *** tensile elongation increased by to the addition of 0.01%carbon black(from 15.8%to 17.4%)due to the increased work hardening effect,but decreased with additional carbon black due to its agglomeration and poor dispersion at higher *** high-ratio differential speed rolling(HRDSR)on the extruded materials and subsequent annealing,the AZ31 and AZ31 composites had a similar fine grain size of 16.3-17.9 *** annealed HRDSR composites showed the best mechanical properties at a higher content of carbon black(0.03%)compared to that(0.01%)for the extruded *** resulted from the enhanced dispersion effect of the carbon black due to the high shear flow induced during the HRDSR *** extruded composites exhibited the three distinct hardening stages(stage II,stage III and stage IV),while the annealed HRDSR composites mainly displayed the stage III *** addition of carbon black increased the strain hardening rate at all the strain hardening stages in both of the extruded and annealed HRDSR *** the initial hardening stage,the strain hardening rates of the extruded comp

关键词： Recycling Magnesium alloys chips Carbon black Nanocomposites Extrusion Differential speed rolling

Reply to the note by Li Piani et al.

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