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101.
一种适合于岩石材料的双剪模型 总被引:1,自引:0,他引:1
岩土类材料强度理论分为单剪强度理论、三剪强度理论和双剪强度理论。三类强度理论的典型代表是Mohr -Coulomb强度理论、Drucker-Prager准则和双剪强度理论。单剪强度理论、三剪强度理论和双剪强度理论都有其相应的单元模型 ,分析单元体上对单元体破坏起主要作用的应力 ,建立各应力分量之间的数学关系 ,形成岩土类材料的强度理论。本文分析岩石围压试验和真三轴试验下的破坏及强度特征 ,提出一种适合于岩石材料的双剪模型 ,与三类强度理论建模方法相同 ,可以得出一系列新的强度理论 相似文献
102.
Dr. Naohiro Kameta Dr. Mitsutoshi Masuda Dr. Toshimi Shimizu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(24):8832-8839
In water, synthetic amphiphiles composed of a photoresponsive azobenzene moiety and an oligoglycine hydrogen‐bonding moiety selectively self‐assembled into nanotubes with solid bilayer membranes. The nanotubes underwent morphological transformations induced by photoisomerization of the azobenzene moiety within the membranes, and the nature of the transformation depended on the number of glycine residues in the oligoglycine moiety (i.e., on the strength of intermolecular hydrogen bonding). Upon UV‐light irradiation of nanotubes prepared from amphiphiles with the diglycine residue, trans‐to‐cis isomerization induced a transformation from nanotubes (inner diameter (i.d.) 7 nm), several hundreds of nanometers to several tens of micrometers in length, to imperfect nanorings (i.d. 21–38 nm). The cis‐to‐trans isomerization induced by continuous visible‐light irradiation resulted in the stacking of the imperfect nanorings to form nanotubes with an i.d. of 25 nm and an average length of 310 nm, which were never formed by a self‐assembly process. Time‐lapse fluorescence microscopy enabled us to visualize the transformation of nanotubes with an i.d. of 20 nm (self‐assembled from amphiphiles with the monoglycine residue) to cylindrical nanofibers with an i.d. of 1 nm; shrinkage of the hollow cylinders started at the two open ends with simultaneous elongation in the direction of the long axis. 相似文献
103.
Saira?Hameed Koji?Ikegami Eiji?Sugiyama Shoko?Matsushita Yoshishige?Kimura Takahiro?Hayasaka Yuki?Sugiura Noritaka?Masaki Michihiko?Waki Isao?Ohta Md?Amir?Hossen Mitsutoshi?SetouEmail author 《Analytical and bioanalytical chemistry》2015,407(25):7589-7602
A protocol for the direct analysis of the phospholipid composition in the whole body of adult soil nematode, Caenorhabditis elegans (C. elegans), was developed, which combined freeze-cracking of the exoskeletal cuticle and matrix-assisted laser desorption/ionization-imaging mass spectrometry (MALDI-IMS). Biomolecules in the m/z range from 700 to 900 were more effectively detected in the freeze-cracked than from simple frozen adult nematode bodies. Different distribution of biomolecules was observed in a nematode body when the matrix was applied with a sublimation deposition method. The whole-body IMS technique was applied on genetically deficient mutant C. elegans to combine whole-body lipidomics and genetics, by comparing the fatty acid compositions, especially of the phosphatidylcholine (PC) species, between the wild-type and fat-1 mutants, which lack the gene encoding an n-3 fatty acid desaturase. A significant reduction of PC(20:5/20:5) and PC(20:4/20:5) and a marked increase of PC(20:4/20:4), PC(20:3/20:4), and PC(20:3/20:3) were detected in the fat-1 mutants in positive ion mode. In addition, phospholipid compositions other than PCs were analyzed in negative ion mode. A loss of a possible phosphatidylinositol (PI) with 18:0/20:5 and a compensative accumulation of putative PI(18:0/20:4) were detected in the fat-1 mutants. In conclusion, the whole-body MALDI-IMS technique is useful for the profiling of multiple biomolecules in C. elegans in both intra- and inter-individual levels. 相似文献
104.
Mitsutoshi Kimura Akiyuki Iwata Masahiro Itoh Kazuki Yamada Tsutomu Kimura Noriyuki Sugiura Masaru Ishida Shinzi Kato 《Helvetica chimica acta》2006,89(4):747-783
A series of [(thioacyl)thio]‐ and (acylseleno)antimony and [(thioacyl)thio]‐ and (acylseleno)bismuth, i.e., (RCSS)xMR and (RCOSe)xMR (M = Sb, Bi, R1 = aryl, x = 1–3), were synthesized in moderate to good yields by treating piperidinium or sodium carbodithioates and ‐selenoates with antimony and bismuth halides. Crystal structures of (4‐MeC6H4CSS)2Sb(4‐MeC6H4) ( 9b′ ), (4‐MeOC6H4COSe)2Sb(4‐MeC6H4) ( 12c′ ), (4‐MeOC6H4COS)2Bi(4‐MeC6H4) ( 15c′ ), and (4‐MeOC6H4CSS)2BiPh ( 18c ) along with (4‐MeC6H4COS)2SbPh ( 6b ) and (4‐MeC6H4COS)3Sb ( 7b ) were determined (Figs. 1 and 2). These compounds have a distorted square pyramidal structure, where the aryl or carbothioato (= acylthio) ligand at the central Sb‐ or Bi‐atom is perpendicular to the plane that includes the two carbodithioato (= (thioacyl)thio), carboselenato (= acylseleno), or carbothioato ligand and exist as an enantiomorph pair. Despite the large atomic radii, the C?S ??? Sb distances in (RCSS)2MR1 (M = As, Sb, Bi; R1 = aryl) and the C?O ??? Sb distances in (RCOS)xMR (M = As, Sb, Bi; x = 2, 3) are comparable to or shorter than those of the corresponding arsenic derivatives (Tables 2 and 3). A molecular‐orbital calculation performed on the model compounds (MeC(E)E1)3?xMMex (M = As, Sb, Bi; E = O, S; E1 = S, Se; x = 1, 2) at the RHF/LANL2DZ level supported this shortening of C?E ??? Sb distances (Table 4). Natural‐bond‐orbital (NBO) analyses of the model compounds also revealed that two types of orbital interactions nS → σ and nS → σ play a role in the (thioacyl)thio derivatives (MeCSS)3?xMMex (x = 1, 2) (Table 5). In the acylthio‐MeCOSMMe2 (M = As, Sb, Bi), nO → σ contributes predominantly to the orbital interactions, but in MeCOSeSbMe2, none of nO → σ and nO → σ contributes to the orbital interactions. The nS → σ and nS → σ orbital interactions in the (thioacyl)thio derivatives are greater than those of nO → σ and nO → σ in the acylthio and acylseleno derivatives (MeCOE)3?xMMex (E = S, Se; M = As, Sb, Bi; x = 1, 2). ?The reactions of RCOSeSbPh2 (R = 4‐MeC6H4) with piperidine led to the formation of piperidinium diphenylselenoxoantimonate(1?) (= piperidinium diphenylstibinoselenoite) (H2NC5H10)+Ph2SbSe?, along with the corresponding N‐acylpiperidine (Table 6). Similar reactions of the bis‐derivatives (RCOSe)2SbR1 (R, R1 = 4‐MeC6H4) with piperidine gave the novel di(piperidinium) phenyldiselenoxoantimonate(2?) (= di(piperidinium) phenylstibonodiselenoite), [(H2NC5H10)+]2(PhSbSe2)2?, in which the negative charges are delocalized on the SbSe2 moiety (Table 6). Treatment of RCOSeSbR (R, R1 = 4‐MeC6H4) with N‐halosuccinimides indicated the formation of Se‐(halocyclohexyl) arenecarboselenoates (Table 8). Pyrolysis of bis(acylseleno)arylbismuth at 150° gave Se‐aryl carboselenoates in moderate to good yields (Table 9). 相似文献
105.
Mitsutoshi Kuroda Viggo Tvergaard 《Journal of the mechanics and physics of solids》2008,56(8):2573-2584
For higher-order gradient crystal plasticity, a finite deformation formulation is presented. The theory does not deviate much from the conventional crystal plasticity theory. Only a back stress effect and additional differential equations for evolution of the geometrically necessary dislocation (GND) densities supplement the conventional theory within a non-work-conjugate framework in which there is no need to introduce higher-order microscopic stresses that would be work-conjugate to slip rate gradients. We discuss its connection to a work-conjugate type of finite deformation gradient crystal plasticity that is based on an assumption of the existence of higher-order stresses. Furthermore, a boundary-value problem for simple shear of a constrained thin strip is studied numerically, and some characteristic features of finite deformation are demonstrated through a comparison to a solution for the small deformation theory. As in a previous formulation for small deformation, the present formulation applies to the context of multiple and three-dimensional slip deformations. 相似文献
106.
Gas-phase E.P.R. spectra of 35ClO have been measured accurately both in the J=5/2 and J=3/2 rotational levels, using C-band (4·4 GHz) and X-band (9·4 GHz) microwaves, respectively. Special attention has been paid to separate the spectral lines of 35ClO from those of 37ClO. Analysis of the spectra has resulted in the simultaneous determination of the hyperfine parameters h and b and, when combined with a-(b+c)/2 obtained by microwave spectroscopy, the hyperfine parameters a, b and c are all determined. Molecular constants which describe the distribution of the unpaired electron around the chlorine nucleus are derived from them. The molecular g values of the rotational levels indicate the mixing of the 2Π state both with the 2Σ+ and with the 2Δ electronic excited states. 相似文献
107.
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110.
Mitsutoshi Kuroda Viggo Tvergaard 《International Journal of Solids and Structures》2009,46(25-26):4396-4408
The finite deformation version of the higher-order gradient crystal plasticity model proposed by the authors is applied to solve plane strain boundary value problems, in order to obtain an understanding of the effect of the higher-order boundary conditions. Numerical solutions are carried out for uniaxial plane strain compression of a single crystal block and for uniform pure bending of a single crystal foil. The compressed block has loading surfaces that are penetrable or impenetrable to dislocations. This allows for a study of the two types of higher-order boundaries available, and a significant effect of higher-order boundary conditions on the overall deformation mode of the block is observed. The bent foil has free surfaces through which dislocations can go out of the material, and we observe a strong size-dependent mechanical response resulting from the surface condition assumed. 相似文献