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961.
The Langevin equations for a particle of an arbitrary shape and the correlation functions for the fluctuating forces, torques, or force-torque acting on the particle in a rotating flow are derived from the semimicroscopic level of coarse graining by using fluctuating hydrodynamics. In order to obtain the solution of the Navier-Stokes Langevin equation valid over the entire flow region, use is made of the method of matched asymptotic expansions in ( f a2/v)1/2 1. The cases of slow and rapid rotation are analyzed. It is shown that the fluctuation-dissipation theorems hold up to the order of ( f a2/v)1/2 in both slow and rapid rotation, and that the diffusivity tensor depends on the angular velocity of the fluid and becomes anisotropic.  相似文献   
962.
We investigated the synergistic wound‐healing effects of D ‐glucosamine (GlcN) and collagen peptide ( : 10 000 Daltons soluble collagen (S‐Co)) on injured cartilage. A injured cartilage model in rabbit was surgically created. Under general anesthesia, three holes at articular cartilage of the medial trochlear (one hole) and trochlear sulcus (two holes) of a distal femur were created using a high‐speed orthopedic drill. After surgery, rabbits were orally administered with collagen peptide (S‐Co group), GlcN (G group), or both (CoG group) for 2 or 3 weeks. In addition, glycine (Gly group) was administered as a control for the S‐Co group in three rabbits. Control rabbits were provided with water ad lib. After 2 weeks, the holes were filled by fibroblasts and chondroblasts in the treatment group, whereas in the control group, the holes were not filled completely unlike for the treatment group. Even three weeks later, only a small change was seen in the control group. In the group receiving collagen and GlcN, the holes were completely filled by proliferating chondroblasts, remodeling of bony trabeculae was also observed. Image analysis of Safranin O‐ and Alcian blue‐stained specimens showed increased production of proteoglycans and glycosaminoglycans, respectively, not only in the injured site, but also in the normal cartilage in the treated groups. The most enhanced healing of injury and increase in Safranin O and Alcian blue positive materials was observed in the CoG group. As a result, simultaneous administration of collagen and GlcN gave a fairly enhanced healing on restoration of cartilage injuries.

Artificial cartilage injury at the stifle joint of a rabbit. a: proximal hole in trochlear sulcus; b: distal hole in trochlear sulcus; c: medial hole in medial trochlear ridge.  相似文献   

963.
Hydrogenation of methyl 3,5-dioxohexanoate 3 using Ru2Cl4((R) or (S)-binap)2(NEt3) as the catalyst gave dominantly anti 3,5-dihydroxyester 9, which was then converted into unsaturated lactone 4. The pathway of the hydrogenation reaction was also investigated.  相似文献   
964.
The use of molecularly imprinted polymers polymerized in a capillary for the separation of amino acid enantiomers by electrochromatography is described. The substrate-selective polymers were prepared by using l-phenylalanine anilide as print molecule and methacrylic acid as the functional monomer. The treatment of the inside surface of the capillary, the composition of the polymer and the electrochromatographic running conditions were investigated. This preliminary report demonstrated a novel and simple method for capillary electrochromatographic separations of amino acid enantiomers using molecularly imprinted polymers. Received: 9 April 1996 / Revised: 8 August 1996 / Accepted: 8 August 1996  相似文献   
965.
用高效液相色谱跟踪2-甲基-7-亚甲基-1,4,6-三氧螺[4,4]壬烷(MMTN)与丙烯腈(AN),丙烯酸甲酯(MA)的共聚合反应。根据Lowry-Meyer共聚积分方程式,采用插值法进行数据拟合测定单体的竞聚率。对于体系MMTN(M_1)-AN(M_2),r_1=0.048;r_2=0.213;MMTN(M_1)-MA(M_2)r_1=0.025,r_2=0.764。说明两组共聚体系均有较强的交替共聚趋势。  相似文献   
966.
Summary LetGG be real reductive Lie groups and q a -stable parabolic subalgebra of Lie (G) . This paper offers a sufficient condition on (G, G, q) that the irreducible unitary representation ofG with non-zero continuous cohomology splits into a discrete sum of irreducible unitary representations of a subgroupG, each of finite multiplicity. As an application to purely analytic problems, new results on discrete series are also obtained for some pseudo-Riemannian (non-symmetric) spherical homogeneous spaces, which fit nicely into this framework. Some explicit examples of a decomposition formula are also found in the cases whereA q is not necessarily a highest weight module.Oblatum 3-IV-1993The author is supported by the NSF grant DMS-9100383.  相似文献   
967.
We have studied the heavy flavored hadron spectroscopy, which is motivated by the heavy quark effective theory. TheQ \(\bar q\) ,Qqq andQQq hadrons have been investigated systematically. Regarding thes-quark as a member of heavy quarks, the predicted mass levels of both theQqq andQQq baryons are quite consistent with experimental ones.  相似文献   
968.
The Baker's yeast reduction of 1-(1,3-dithian-2-yl)-1,2-propanedione gave highly enantio-and diastereoselectively (S)-(+)-(1-1,3-dithian-2-yl)-2-hydroxy-1-propanone or (1S,23-(+)-(1)-(1,3-dithian-2-yl-1,2-propanediol, depending on the reaction time. The hydroxy ketone was reduced with diisobutylaluminum hydride to give (1R,2S)-1-(1,3-dithian-2-yl)-1,2-propanediol with high diastereoselectivity. The former (1S,2S)-diol was converted into L-digitoxose.  相似文献   
969.
The effect of bulky N-substitutents of N-t-butyl- and N-phenyl-N-allylmethacrylamides (BAMA and PAMA, respectively) on their cyclopolymerizability was investigated. BAMA yielded an almost completely cyclized polymer while the degree of cyclization of poly (PAMA) was about 95%. The latter value indicates that the effect of phenyl group is comparable with that of methyl group, since N-methyl-N-allylmethacrylamide was reported to give a polymer with a degree of cyclization of 93%. Structural investigation on telomerization products of BAMA and PAMA permitted the assignment of the repeating cyclic units of these polymers to that of a five-membered ring. This structural characteristic was also supported by the observation of five-membered cyclized radicals on ESR measurements of these monomers. Rotation around amide C? N bonds of these monomers and related compounds studied by 13C-NMR was found to be strongly dependent on N-substitutents. The mechanism of the cyclization was discussed in terms of the structure of the ring formed and rotation around amide C? N bonds of these monomers. The reactivity of the methacryloyl and allyl groups involved in these monomers were compared based on the information obtained by structural investigation of polymers and telomerization products and by ESR studies. © 1993 John Wiley & Sons, Inc.  相似文献   
970.
Synthesis of optically active 2,3-dihydrofuran derivatives has been accomplished through a combination strategy of ferric ion-catalyzed cycloaddition of styrene derivatives with quinones and following lipase-catalyzed enantioselective acylation.  相似文献   
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