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101.
Let and be a sufficiently large real number. In this paper, we prove that, for almost all , the Diophantine inequality is solvable in primes . Moreover, we also investigate the problem of six primes and prove that the Diophantine inequality is solvable in primes for sufficiently large real number . 相似文献
102.
混合幂的素变数丢番图逼近 总被引:1,自引:0,他引:1
证明了:如果λ_1,λ_2,λ_3,λ_4是正实数,λ_1/λ_2是无理数和代数数,V是well-spaced序列,δ0,那么对于v∈V,v≤X,ε0,使得|λ_(1p_1~2)+λ_(2p_2~2)+λ_(3p_3~3)+λ_(4p_4~3)-v|v~(-δ)没有素数解p1,p2,p3,p4的v的个数不超过O(X~(20/21+21δ+ε)). 相似文献
103.
Thomas R. Nicely. 《Mathematics of Computation》1999,68(227):1311-1315
The search for first occurrences of prime gaps and maximal prime gaps is extended to . New maximal prime gaps of 806 and 906 are found, and sixty-two previously unpublished first occurrences are found for gaps varying from 676 to 906.
104.
LunChuanZHANG 《数学学报(英文版)》2003,19(2):413-416
The relation between the inseparable prime C^*-algebras and primitive C^*-algebras is studied,and we prove that prime AW^*-algebras are all primitive C^*-algebras. 相似文献
105.
A. D. Grebenyuk V. I. Vinogradova A. K. Tashmukhamedova 《Chemistry of Natural Compounds》2004,40(5):503-505
New disulfamides of dibenzo-18-crown-6 with salsolidine, salsoline, and anabasine were prepared by condensation of the corresponding alkaloids with 4,4(5)-dibenzo-18-crown-6-disulfonyl chlorides.Presented at the 5th International Symposium on the Chemistry of Natural Compounds (Tashkent, Uzbekistan, May 20–23, 2003).Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 413–415, September–October, 2004. 相似文献
106.
Linko R. V. Belsky V. K. Varlamov A. V. Zaitsev B. E. Chernyshev A. I. 《Russian Chemical Bulletin》2001,50(9):1625-1629
The addition of acetone to 9,10-phenanthrenequinone and 2-nitro-, 2,7-dinitro-, and 2,4,7-trinitro-9,10-phenanthrenequinones in the presence of Al2O3 affords mono- and bisadducts. The crystal structures of 10-hydroxy-10-(2-oxopropyl)-2-nitro-9,10-dihydrophenanthren-9-one and 9,10:10,9-bishemiketal of 9,10-dihydroxy-2-nitro-9,10-bis(2-oxopropyl)-9,10-dihydrophenanthrene were determined. 相似文献
107.
108.
一种基于扩展素数码和单重合序列的二维光正交码EPC/OCS 总被引:1,自引:0,他引:1
以扩展素数码(EPC)作为时间扩频伪随机序列,单重合序列(OCS)作为波长跳频伪随机序列,构造了一种新的二维光正交码EPC/OCS,并分析了码字的互相关性能.与修正素数跳频码MPHC相比,EPC/OCS的波长数并不局限于素数,可以是任意整数,不仅构造灵活,而且可充分利用MW OCDMA系统的有效波长数.当系统的有效波长数大于某个素数时,EPC/OCS不仅码字容量大于MPHC,而且互相关性能也有所改善.理论分析表明,EPC/OCS可降低MW OCDMA系统误码率. 相似文献
109.
曹洪平 《数学年刊A辑(中文版)》2004,(6)
设G是有限群,πe(G)表示G中元素的阶的集合,h(πe(G))表示满足πe(H)=πe(G)条件的有限群H的同构类类数,本文证明了例外型Chevalley群G2(q)的h函数值为1或∞. 相似文献
110.
The ionic strength and temperature dependencies of the molal acid association quotients of 2,2-Bis(hydroxymethyl)-2,2,2-nitrilotriethanol (also abbreviated as bis-tris) were determined potentiometrically in a concentration cell fitted with hydrogen electrodes. The emf was recorded for equimolal bis-tris/bis- trisHCl buffer solutions from 5 to 125°C at approximately 25°C intervals, and at nine ionic strengths from 0.05 to 5.0m (NaCl). The molal association quotients, combined with infinite dilution values from the literature, are described precisely by a seven parameter equation which yielded the following thermodynamic quantities at infinite dilution and 25°C: logK=6.481±0.003, H
o
=–28.5±0.2 kJ-mol
–1
, S
o
=28.5±0.8 J-K
–1
-mol
–1
, and C
P
o
=–22±5 J-K
–1
-mol
–1
. The equation incorporates a simple three term expression for logK, but requires four terms to describe the rather complex ionic strength dependence despite the reaction being isocoulombic. The molal association quotients from this study and the literature were also subjected to the Pitzer ion interaction treatment. 相似文献