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71.
72.
M. M. Shemyakin Yu. A. Ovchinnikov A. A. Kiryushkin V. T. Ivanov 《Russian Chemical Bulletin》1962,11(12):2061-2067
73.
The influence of phase transition (PT) on the process of thermal development of a latent image arising after X-ray and uv irradiation of ammonium perchlorate (AP) crystals has been studied. Despite the production of a large number of new dislocations accompanying PT, it essentially does not influence the thermal development: The developed image does not smear at PT, remaining as clear as before it. By comparing mirror-symmetric surfaces of cleavage planes of AP crystals, it has been shown that at doses of X-ray and uv irradiation sufficient for obtaining an image, no production of new dislocations was observed in AP crystals. It is suggested that latent image arises due to formation during irradiation of chlorine oxidic products of radiolysis: ClO3, ClO2, and ClO as well as the corresponding ions ClO?, ClO?2, and ClO?3, i.e., initiators of AP low-temperature decomposition. 相似文献
74.
75.
76.
Ivanov R. A. Korsakov I. E. Formanovskii A. A. Paramonov S. E. Kuz'mina N. P. Kaul' A. R. 《Russian Journal of Coordination Chemistry》2002,28(9):670-672
A new simple method of synthesis of heteroligand complexes [Ln(Dalkdtc)3Phen] (Ln = Eu or Er; Dalkdtc is the dialkyldithiocarbamate ion, Phen is o-phenanthroline) in an aqueous solution is described; the possibility of using the complexes as initial reagents for the synthesis of rare-earth sulfides is shown. 相似文献
77.
A. A. Yavolovskii O. S. Timofeev É. I. Ivanov 《Chemistry of Heterocyclic Compounds》1998,34(8):976-978
Methods are reported for preparing the novel pyrimidines 7,8-dihydro-9H-1,2,5-chalcodiazolo[3,4-d]thiazole[2,3-b]pyrimidin-4-ones and their N-oxides.A. V. Bogatskii Physicochemical Institute, National Academy of Sciences of Ukraine, Odessa, 270080. Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 8, pp. 1130–1132, August, 1998. 相似文献
78.
Tramontano A Ivanov B Gololobov G Paul S 《Applied biochemistry and biotechnology》2000,83(1-3):233-243
Reactive phosphonate diesters were designed and prepared as inhibitors of serine proteases and esterases. Inactivation of
trypsin, chymotrypsin, and butyrylcholinesterase was determined by residual enzymaticactivity as well as by the release of
a chromogenic or fluorogenic product of the inhibition reaction. Second-order rate constants were determined from rates of
nitrophenol formation. Application of the reaction for active-site titration of enzyme preparations is demonstrated. A basic
functional group present in the nitrophenyl tropane phosphonate diester was shown to confer selectivity for inactivation of
try psin and chymotrypsin. Biotinylated derivatives of the phosphonate diesters were prepared to permitanalysis of proteins
modified in the inhibition reaction. Labeled polypeptides were resolved by SDSPAGE, electroblotted, and detected by streptavidin-peroxidase
staining. A detection limit of less than 4 ng, corresponding to 20 nM of trypsin, was demonstrated. Pretretment of enzymes
with DFP or nonbiotinylated phosphonates specifically blocks the labeling. This technique permits identification of serine
proteases in complex mixtures with good sensitivity and specificity. 相似文献
79.
N. V. Ivanov 《Journal of Mathematical Sciences》1984,26(1):1646-1664
The goal of the paper is to calculate the homotopy type of the space of diffeomorphisms for most orientable three-dimensional manifolds with finite fundamental group containing the Klein bottle. The fundamental group of such a manifold Q has the form <a, b ¦abab
–1=1,a
mb2n=1>. As m and n one can have any relatively prime natural numbers; these numbers m, n determine the manifold Q up to diffeomorphism. Let K be a Klein bottle lying in Q and let P be a closed tubular neighborhood in Q of this Klein bottle K. We denote by Diffo(Q) the connected component of the space of diffeomorphisms QQ containing id Q, and by E0(K, Q) the connected component of the space of imbeddings KQ containing the inclusion KQ; analogously we define E0(K, P). The main results of the paper are the following two theorems. THEOREM 1. If m, n1, then the space Diffo(Q) is homotopy equivalent with a circle. THEOREM 2. If m, n1, then the inclusion E0(K, P) E0(K, Q) is a homotopy equivalence. With the help of familiar results on spaces of diffeomorphisms of irreducible manifolds which are sufficiently large, Theorem 1 reduces without difficulty to Theorem 2. The main difficulty is the proof of Theorem 2. This proof develops a technique of Hatcher and the author which deals with spaces of PL-homeomorphisms and diffeomorphisms of irreducible manifolds which are sufficiently large. In the paper we use a different structure definition of the class of manifolds considered. It is easy to verify that these definitions are equivalent.Translated from Zapiski Nauchnykh Seminarov Leningradskogo Otdeleniya Matematicheskogo Instituta im. V. A. Steklova AN SSSR, Vol. 122, pp. 72–103, 1982. 相似文献
80.
V. A. Ivanov 《Mathematical Notes》1978,23(1):3-16
For anyx ∈ r put $$c(x) = \overline {\mathop {\lim }\limits_{t \to \infty } } \mathop {\min }\limits_{(p,q\mathop {) \in Z}\limits_{q \leqslant t} \times N} t\left| {qx - p} \right|.$$ . Let [x0; x1,..., xn, ...] be an expansion of x into a continued fraction and let \(M = \{ x \in J,\overline {\mathop {\lim }\limits_{n \to \infty } } x_n< \infty \}\) .Forx∈M put D(x)=c(x)/(1?c(x)). The structure of the set \(\mathfrak{D} = \{ D(x),x \in M\}\) is studied. It is shown that $$\mathfrak{D} \cap (3 + \sqrt 3 ,(5 + 3\sqrt 3 )/2) = \{ D(x^{(n,3} )\} _{n = 0}^\infty \nearrow (5 + 3\sqrt 3 )/2,$$ where \(x^{(n,3)} = [\overline {3;(1,2)_n ,1} ].\) This yields for \(\mu = \inf \{ z,\mathfrak{D} \supset (z, + \infty )\}\) (“origin of the ray”) the following lower bound: μ?(5+3√3)/2=5.0n>(5 + 3/3)/2=5.098.... Suppose a∈n. Put \(M(a) = \{ x \in M,\overline {\mathop {\lim }\limits_{n \to \infty } } x_n = a\}\) , \(\mathfrak{D}(a) = \{ D(x),x \in M(a)\}\) . The smallest limit point of \(\mathfrak{D}(a)(a \geqslant 2)\) is found. The structure of (a) is studied completely up to the smallest limit point and elucidated to the right of it. 相似文献