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101.
Fumiko Ohtsuka 《Geometriae Dedicata》1991,38(2):151-157
The theory of the ideal boundary has arisen as a method of a study of noncompact manifolds. In this paper we shall investigate properties of manifolds whose ideal boundaries satisfy some conditions related to the Tits metric. In Section 2 we shall consider in what conditions the Tits topology is equivalent to the sphere topology and in Section 3 the property of points at infinity which characterize the R-factor. Furthermore, in Section 4 we shall give a sufficient condition for a projective map to be isometríc.Partially supported by Grant-in-Aid for Encouragement of Young Scientists (No. 01740011), The Ministry of Education, Science and Culture, Japan. 相似文献
102.
Ditzler WR Hill D Hoftiezer J Johnson KF Lopiano D Shima T Shimizu H Spinka H Stanek R Underwood D Wagner RG Yokosawa A Burleson GR Faucett JA Fontenla CA Garnett RW Luchini C Rawool-Sullivan MW Bhatia TS Glass G Hiebert JC Kenefick RA Nath S Northcliffe LC Damjanovich R Jarmer JJ Vaninetti J Jeppesen RH Tripard GE 《Physical review D: Particles and fields》1992,46(7):2792-2830
103.
104.
Protein stability is enhanced by the addition of osmolytes, such as sugars and polyols and inert crowders, such as polyethylene glycols. This stability enhancement has been quantified by the preferential hydration parameter which can be determined by experiments. To understand the mechanism of protein stability enhancement, we present a statistical mechanical analysis of the preferential hydration parameter based upon Kirkwood-Buff theory. Previously, the preferential hydration parameter was interpreted in terms of the number of hydration waters, as well as the cosolvent exclusion volume. It was not clear how accurate these interpretations were, nor what the relationship is between the two. By using the Kirkwood-Buff theory and experimental data, we conclude that the contribution from the cosolvent exclusion dominantly determines the preferential hydration parameters for crowders. For osmolytes, although the cosolvent exclusion largely determines the preferential hydration parameters, the contribution from hydration may not be negligible. 相似文献
105.
The brightness of the X‐ray source in a W/Al‐film target used for X‐ray projection microscopy was studied by an approach using the Monte Carlo simulation. Since continuous X rays generated in a thin film have a specific angular distribution of emission, the brightness of the continuous X‐ray source cannot simply be estimated on the assumption that the angular distribution is homogeneous. The newly developed approach using the Monte Carlo simulation enables the evaluation of the effective source size, angular distribution, and brightness of a continuous X‐ray source with sufficient accuracy that it leads to the optimum design of a high‐brightness X‐ray source for uses such as X‐ray projection microscopy. The Monte Carlo calculations were performed for W(Δz)/Al (200 µm)‐film targets with different thicknesses of W film, Δz, under bombardment of 60 kV electrons. The results have suggested an optimum design consisting of a W (2 µm)/Al (200 µm)‐film target as most promising for providing an X‐ray source of higher brightness than the W (5 µm)/Al (200 µm)‐film target, which has already been in practice for X‐ray projection microscopy. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
106.
I. Shimizu H. Okabayashi N. Hattori K. Taga A. Yoshino C. J. O’Connor 《Colloid and polymer science》1997,275(3):293-297
Changes in the 13C and 1H NMR chemical shifts of the silane coupling agent (3-aminopropyltri-ethoxysilane, APTS) in toluene, which were detected as
the concentration of APTS increased, have been interpreted in terms of the formation of micelles and the presence of a critical
micelle concentration (CMC) equal to ca. 0.47 mol 1-1. For the protons of the n-propyl segment, 1H NMR splitting patterns have been analyzed and conformations of the propyl segment have been discussed. Plots of relative
absorbance of the two NH2 stretch IR bands at 3324 and 3384 cm-1 against concentration provided an inflection point (corresponding to the CMC) at a value equal to 0.46 mol 1-1. Thus, consideration of the interaction of APTS with a surface must take into account the presence of both APTS aggregates
as well as APTS monomers.
Received: 16 August 1996 Accepted: 26 September 1996 相似文献
107.
Reaction of ketene silyl acetals with allylic carbonates in the presence of palladium-phosphine catalyst in dioxane gives α-allyl esters in high yields. When the reaction is carried out with phosphine-free palladium catalyst in nitriles, α,β-unsaturated esters are obtained in good yields. 相似文献
108.
Kondo M Irie Y Shimizu Y Miyazawa M Kawaguchi H Nakamura A Naito T Maeda K Uchida F 《Inorganic chemistry》2004,43(20):6139-6141
Reversible construction of a nanoporous framework from a nonporous framework has been found in the zinc(II) coordination polymer with 4,4'-oxybis(benzoate) (oba). [Zn(2)(oba)(2)(dmf)(2)].2DMF (1), which has 1 nm scale channels, transforms to the nonporous coordination polymer [Zn(oba)(H(2)O)] (2) with the loss of the open framework. Compound 2 on treatment with DMF reversibly yields nanoporous compound 1. 相似文献
109.
T Shimizu T Masuzawa Y Yanagihara H Itoh S Nakamoto K Achiwa 《Chemical & pharmaceutical bulletin》1989,37(9):2535-2536
The mitogenicity and lethal toxicity of chemically synthesized lipid A analogs, in which 2,3-acyloxyacylglucosamine-4-phosphate (acyl-GlcN-4P) is linked to a tetraacetyl (Ac4)-monosaccharide, i.e., Ac4-glucose (A-211), Ac4-mannose (A-212), Ac4-galactose (A-213) or Ac4-glucosamine (A-214), were compared with those of tetraacetyl-3-deoxy-D-manno-2-octulosonic acid (Ac4-KDO) linked to acyl-GlcN-4P (A-203). All the compounds were capable of increasing incorporation of 3H-thymidine into splenocytes of C57BL/6 mice at doses of 50 and 100 micrograms/ml, but the mitogenic activity of A-203 at these doses seems to be stronger than those of the analogs. Intravenous injection of A-203, A-211, and A-213 did not exhibit lethal toxicity even at a high dose (50 micrograms/mouse) in C57BL/6 mice loaded with D-galactosamine hydrochloride. However, A-212 and A-214 showed lethality at the doses of 10 and 50 micrograms/mouse, respectively. The findings indicate that the biological activity of these compounds is affected by the kind of monosaccharide linked to acyl-GlcN-4P. 相似文献
110.
Masaki Shimizu Prof. Dr. Takuya Kurahashi Dr. Katsuhiro Shimono Dr. Kei Tanaka Ikuhiro Nagao Shin‐ichi Kiyomoto Tamejiro Hiyama Prof. Dr. 《化学:亚洲杂志》2007,2(11):1400-1408
Treatment of 1,1‐bis(pinacolatoboryl)ethene with an excess of 1‐bromo‐1‐lithioethene gave 2,3‐bis(pinacolatoboryl)‐1,3‐butadiene in high yield. Palladium‐catalyzed cross‐coupling of the resulting diborylbutadiene with aryl iodides took place smoothly in the presence of a catalytic amount of Pd(OAc)2/PPh3 and aqueous KOH to give 2,3‐diaryl‐1,3‐butadienes in good yields. The coupling reaction with commercially available 4‐acetoxyphenylmethyl chloride under the same conditions followed by hydrolysis of the acetyl groups gave anolignan B in a one‐pot manner. A variety of [3]‐ to [6]dendralenes were synthesized by palladium‐catalyzed coupling of the diene or 1,1‐bis(pinacolato)borylethene with alkenyl or dienyl halides, respectively, in good yields. 相似文献