通过Internet发送敏感信息时,务必留神Kevin Mitnick们。采用一次性加密方法的POTP (Power One Time Pad)Secure FTP和POTP SecurE-mail产品(Elementrix出品)提供了一条快捷、简便而高效的途径,可将那些总是心怀叵测的“黑客”们拒之门...通过Internet发送敏感信息时,务必留神Kevin Mitnick们。采用一次性加密方法的POTP (Power One Time Pad)Secure FTP和POTP SecurE-mail产品(Elementrix出品)提供了一条快捷、简便而高效的途径,可将那些总是心怀叵测的“黑客”们拒之门外。 一次性加密方法为每条已译码消息指派随机生成的解密键,这样在理论上可以令入侵更为困难。发送方和接收方都必须使用相同的加密产品。当有人试图侵扰。展开更多
The present work describes a facile, one-pot three component environment friendly, green synthesis of a series of 5-（4-methoxyphenyl）-7,7-dimethyl-10-phenyl-7,8-dihydro-SH-indeno[ 1,2-b]quinoline- 9,11 （6H,10H）-di...The present work describes a facile, one-pot three component environment friendly, green synthesis of a series of 5-（4-methoxyphenyl）-7,7-dimethyl-10-phenyl-7,8-dihydro-SH-indeno[ 1,2-b]quinoline- 9,11 （6H,10H）-dione derivatives 8（a-n）. 1,3-indanedione, awl-aldehyde and enaminone was thoroughly ground in the presence of catalytic amount of p-toluene sulfonic acid （p-TSA） to give the titled compounds in good yields. All the synthesized derivatives were evaluated for their anticonvulsant activity using the maximal electroshock （MES） method with phenytoin as a standard drug along with their neurotoxicity effect. Derivatives 8b, 8e and 8k exhibited significant anticonvulsant activity （P 〈 0.001）. The neurotoxicity study clearly revealed that all the tested compounds are non-toxic at a dose of 40 mg/kg. The molecular modeling studies also predicted good binding interactions of most active molecules with the serotonin 5-HT2A receptor. Therefore, it can be safely concluded that synthesized derivatives 8（a-n） would represent useful leads for further investigation in the development of a new class of anticonvulsant agents.展开更多
Let (X, d) be a bounded metric space and f : X → X be a uniformly continuous surjection. For a given dynamical system (X, f) which may not be compact, we investigate the relation between the asymptotic average shadow...Let (X, d) be a bounded metric space and f : X → X be a uniformly continuous surjection. For a given dynamical system (X, f) which may not be compact, we investigate the relation between the asymptotic average shadowing property(AASP), transitivity and mixing. If f has the AASP, then the following statements hold: (1) f n is chain transitive for every positive integer n; (2) If X is compact and f is an expansive homeomorphism, then f is topologically weakly mixing; (3) If f is equicontinuous, then f is topologically weakly mixing; (4) If X is compact and f is equicontinuous, then f ×f is a minimal homeomorphism. We also show that the one-sided shift map has the AASP and the identity map 1 X does not have the AASP. Furthermore, as its applications, some examples are given.展开更多
Let X be a compact metric space and let f:X→X be an Anosov map,i.e.,an expansive selfmap with the pseudoorbit tracing property(abbr.POTP)(see Lemma 1).If Nn(f) denotes the number of fixed points of f^n which we name ...Let X be a compact metric space and let f:X→X be an Anosov map,i.e.,an expansive selfmap with the pseudoorbit tracing property(abbr.POTP)(see Lemma 1).If Nn(f) denotes the number of fixed points of f^n which we name here the n-periodic number then we prove in the case as n tends to infinity that n^M ≤N_n(f)≤H^n,where M and H are two positive integers.展开更多
文摘通过Internet发送敏感信息时,务必留神Kevin Mitnick们。采用一次性加密方法的POTP (Power One Time Pad)Secure FTP和POTP SecurE-mail产品(Elementrix出品)提供了一条快捷、简便而高效的途径,可将那些总是心怀叵测的“黑客”们拒之门外。 一次性加密方法为每条已译码消息指派随机生成的解密键,这样在理论上可以令入侵更为困难。发送方和接收方都必须使用相同的加密产品。当有人试图侵扰。
文摘The present work describes a facile, one-pot three component environment friendly, green synthesis of a series of 5-（4-methoxyphenyl）-7,7-dimethyl-10-phenyl-7,8-dihydro-SH-indeno[ 1,2-b]quinoline- 9,11 （6H,10H）-dione derivatives 8（a-n）. 1,3-indanedione, awl-aldehyde and enaminone was thoroughly ground in the presence of catalytic amount of p-toluene sulfonic acid （p-TSA） to give the titled compounds in good yields. All the synthesized derivatives were evaluated for their anticonvulsant activity using the maximal electroshock （MES） method with phenytoin as a standard drug along with their neurotoxicity effect. Derivatives 8b, 8e and 8k exhibited significant anticonvulsant activity （P 〈 0.001）. The neurotoxicity study clearly revealed that all the tested compounds are non-toxic at a dose of 40 mg/kg. The molecular modeling studies also predicted good binding interactions of most active molecules with the serotonin 5-HT2A receptor. Therefore, it can be safely concluded that synthesized derivatives 8（a-n） would represent useful leads for further investigation in the development of a new class of anticonvulsant agents.
基金Supported by the NSF of Guangdong Province(10452408801004217)Supported by the Key Scientific and Technological Research Project of Science and Technology Department of Zhanjiang City(2010C3112005)
文摘Let (X, d) be a bounded metric space and f : X → X be a uniformly continuous surjection. For a given dynamical system (X, f) which may not be compact, we investigate the relation between the asymptotic average shadowing property(AASP), transitivity and mixing. If f has the AASP, then the following statements hold: (1) f n is chain transitive for every positive integer n; (2) If X is compact and f is an expansive homeomorphism, then f is topologically weakly mixing; (3) If f is equicontinuous, then f is topologically weakly mixing; (4) If X is compact and f is equicontinuous, then f ×f is a minimal homeomorphism. We also show that the one-sided shift map has the AASP and the identity map 1 X does not have the AASP. Furthermore, as its applications, some examples are given.
文摘Let X be a compact metric space and let f:X→X be an Anosov map,i.e.,an expansive selfmap with the pseudoorbit tracing property(abbr.POTP)(see Lemma 1).If Nn(f) denotes the number of fixed points of f^n which we name here the n-periodic number then we prove in the case as n tends to infinity that n^M ≤N_n(f)≤H^n,where M and H are two positive integers.
