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101.
Yoshio Imai Kazuo Itoya Masami Kanamaru Masa‐Aki Kakimoto 《Journal of polymer science. Part A, Polymer chemistry》2002,40(11):1790-1795
New phenolic hydroxyl‐pendant aromatic polyimides were synthesized with the N‐silylated diamine method in two steps: the ring‐opening polyaddition of tetrakis(trimethylsilyl)‐substituted 4,4′‐diamino‐3,3′‐dihydroxybiphenyl to various aromatic tetracarboxylic dianhydrides, giving trimethylsiloxy‐pendant poly(amic acid) trimethylsilyl esters, and thermal imidization. The hydroxyl‐bearing polyimides were amorphous but insoluble in organic solvents. They had glass‐transition temperatures greater than 370 °C and temperatures of 10% weight loss greater than 415 °C in nitrogen. The hydroxyl‐pendant polypyromellitimide film had a high tensile strength and a high modulus of 310 MPa and 10 GPa, respectively. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1790–1795, 2002 相似文献
102.
Sigeo Aki 《Annals of the Institute of Statistical Mathematics》1981,33(1):1-14
Summary In this paper we investigate the effect of estimating the center of symmetry on a Cramér-von Mises type statistic for testing
the symmetry of a distribution function. The test statistic is defined by
whereF
n is the empirical distribution function andS[F
n] is an estimator of the center ofF which is consistent with the ordern
1/2 and has von Mises derivative. The asymptotic distribution ofnT
0[Fn] under the null hypothesis is obtained. The distribution depends on the distributionF and on the estimatorS[F
n].
The Institute of Statistical Mathematics 相似文献
103.
The insertion reaction of isocyanide into a C-S bond of dithioacetals is catalyzed by GaCl3 or TiCl4 to afford thioimidates containing an alpha-alkylthio group. Balanced thiophilicity of these Lewis acids is critical for efficient catalysis. 相似文献
104.
Shimada Y Goto T Kawamoto S Kiso T Katayama A Yamanaka Y Aki T Chiang KC Nakano T Goto S Chen CL Ohmori N Ono K Sato S 《Biomedical chromatography : BMC》2008,22(1):13-19
In organ transplantation, the development of a novel immunosuppressant free of the need for permanent administration and any serious side effects has eagerly been awaited. We have previously reported that an anti-histone H1 polyclonal antibody has immunosuppressant activity. Here we prepared an anti-histone H1 monoclonal antibody as an analytical tool to elucidate its mechanism of immunosuppression. The isotype of this monoclonal antibody was immunoglobulin M. A monoclonal antibody prepared for administration to organ transplantation model animals should not contain any allogenic proteins and should have high purity. Therefore, we conducted a two-step chromatography procedure, consisting of strong anion-exchange chromatography and gel filtration chromatography, to purify an anti-histone H1 monoclonal immunoglobulin M antibody from the serum-free culture supernatant of hybridomas. Consequently, we successfully purified the monoclonal antibody at 96%, a purification rate at which its administration to organ transplantation model animals is possible. 相似文献
105.
106.
107.
Sueli M. Tanaka Aki Sandra M.S. de Godoy 《Nonlinear Analysis: Real World Applications》2009,10(1):172-184
The paper studies a class of a system of linear retarded differential difference equations with several parameters. It presents some sufficient conditions under which no stability changes for an equilibrium point occurs. Application of these results is given. 相似文献
108.
In considering mathematics problem solving as a model-eliciting activity (
[Lesh and Doerr, 2003],
[Lesh and Harel, 2003] and [Lesh and Zawojewski, 2008]), it is important to know what students are modeling for the problems: situations or solutions. This study investigated Grade 3 students’ mathematization process by examining how they modeled different types of multi-digit subtraction situation problems. Students’ modeling processes differed from one problem type to another due to their prior experiences and the complexity of the problems. This study showed that students make their own distinctions between solution and situation models in their mathematization process. Mathematics curricula and teaching should consider these distinctions to carefully facilitate different model development of and support student understanding of a content topic. 相似文献
109.
In this paper, we review the mass probes used for the derivation of a variety of biomolecules efficiently detected by the electrospray ionization-mass spectrometry and mass probe-assisted ionization method for total analysis and determination by consecutive detection with a single instrument. We describe mass probes for a variety of molecules including proteins, nucleobases, metallic cations, and other small molecules. 相似文献
110.
In this paper, we study of Pólya urn model containing balls of (m+1) different labels under a general replacement scheme, which is characterized by an (m+1) × (m+1) addition matrix of integers without constraints on the values of these (m+1)2 integers other than non-negativity. LetX
1,X
2,...,X
n
be trials obtained by the Pólya urn scheme (with possible outcomes: “O”, “1”,...“m”). We consider the multivariate distributions of the numbers of occurrences of runs of different types arising from the various
enumeration schemes and give a recursive formula of the probability generating function. Some closed form expressions are
derived as special cases, which have potential applications to various areas. Our methods for the derivation of the multivariate
run-related distribution are very simple and suitable for numerical and symbolic calculations by means of computer algebra
systems. The results presented here develop a general workable framework for the study of Pólya urn models. Our attempts are
very useful for understanding non-classic urn models. Finally, numerical examples are also given in order to illustrate the
feasibility of our results.
This research was partially supported by the ISM Cooperative Research Program (2003-ISM·CRP-2007). 相似文献