拟AGP-内射模的自同态环

设R为环,MR是拟AGP-内射模,S=End(MR),文章主要研究了S的Jacobson根和半单性.在MR是自生成元时,证明了:1)J(S)=△,其中△={s∈S|kers是M的本质子模};2)若S是满足特殊升链条件的半素环,则S是半单环.从而推广了AGP-内射环的一些结果.     

一类三阶矩阵环的Armendariz和半交换子环

考虑环R上三阶矩阵环M3(R)的一类特殊子环S3(R),证明了如果R是reduced环,α,β是R的相容自同态,则S3(R)是半交换Armendariz环,并给出了Armendariz环和半交换环的例子.     

一类半交换的Armendariz环

通过环R上矩阵环M3(R)的特殊子环S3(R)={(α(a) b c 0 β(a) d 0 0 γ(a))|a,b,c,d∈R}给出了一类半交换Armendariz环。利用Reduced环和相容自同态的性质证明了:如果R是Reduced环,α,β,γ是R的相容自同态,那么S3(R)是半交换的Armendariz环。     

Qnil-半交换环及其扩张

引进了qnil-半交换环的概念,推广了半交换环.证明了:二级三角矩阵环(SM0T)是qnil-半交换环当且仅当环S,T都是qnil-半交换环;环R上的幂级数环R[[x]]是qnil-半交换环当且仅当R是qnil-半交换环.     

拟AGP-内射模的自同态环

设R为环,Mg是拟AGP-内射模,S=End（MR）,文章主要研究了S的Jacobson根和半单性．在MR是自生成元时,证明了：1）J（S）=△,其中△={s∈S｜kers是M的本质子模};2）若S是满足特殊升链条件的半素环,则S是半单环．从而推广了AGP-内射环的一些结果．     

直接有限环

证明了如下结果:1)环R是直接有限环当且仅当每个右R-满射f:R→R是单射;2)若R是右C2环,则R是直接有限环当且仅当每个右R-单射f:R→R是满射当且仅当R/J(R)是直接有限环;3)设R是左半A-bel环,则R是直接有限环;4)设R,S是两个环,RVS是(R,S)双模,则C=RV     

关于拟WGP-内射模

定义了拟WGP-内射模,给出了拟WGP-内射模的一些刻画及性质。设R为环,M是右R-模,S=End(M),证明了MR是一个右拟WGP-内射模当且仅当对于任意的0≠a∈S,存在0≠c∈S,使得ac≠0且lS(ker(ac))=Sac;设M是右拟WGP-内射的自生成子,S半素,则S的每个极大核是M的直和项;设MR是右拟WGP-内射模,对于S的任意右一致元u,Au={s∈S|kers∩u(M)≠0}是包含ls(u(M))的一个极大左理想,从而推广了WGP-内射环的一些结果。     

关于广义内射模的一些研究

论文给出了拟AP-内射模的一些结果.同时,定义了拟AGP-内射模,并且得到了若干结果.如设MR是拟AGP-内射模,并且对任意a∈S,都存在正整数n,使得an(M)是投射的,那么S是π-正则环.并且,因此得到S是左(右)GPP-环.这些推广总结了拟AP-内射模和AGP-内射环的一些结果.     

某些环上的有限直和

证明R是V-环(或GV-环;FS-环;IF-环;FC-环;n-FC环)当且仅当S和T都是V-环(或GV-环;FS-环;IF-环;FC-环;n?FC环),其中S和T是环,R=ST.一般地,当R=im=1Ri时,类似的结论也成立.     

Morphic环的一些性质

文章研究了M orphic环的一些性质,证明了:(1)约化的Morphic环是左(右)遗传的;(2)约化环R是Morphic环■M∈MR,M是平坦模;(3)约化环R是Morphic环■每个循环左R-模是GP-内射的R是左PP环和左GP-内射环。     

拟对偶双边模与对偶环

左拟对偶双边模 _SM_R 可以被刻划成M_R 的任意子模K 和_SS 的任意左理想L 分别是_rM l_S (K ) 和 l_S r_M( L ) 的一个直和项.对一个左拟对偶双边模_SM_R, 有以下结论: ( 1) _SM 为Kasch模; ( 2) r_Ml_S ( Soc( M_R ) ) = Soc(M_R ) , l_S r_M ( Soc( _S^S) ) = Soc( _SS) ;( 3) l_S ( Soc(M_R ) ) J ( S) , r_M ( Soc( _SS) ) Rad(M_R ) ; ( 4) 若 M_R 为 CS- 模,则 Soc( M^R ) _eM_R ; ( 5) 若 M_R 是非M - 奇异的,则M 是半单的; ( 6) 若 M_R 在[ M] 中投射且 M_R 半单,则 M 是非M - 奇异模.并且还得出, 若 R 是左对偶环或左拟对偶环,则R 是半单环当且仅当R 非奇异.     

广义拟P-内射模的性质

把拟AP-内射模的已有性质与拟P-内射模的研究方法 相结合, 给出了拟AP-内射模的一些新性质. 设M_R是拟AP-内射的右R-模, 令S=End(M_R), 则: (1) S是右弱C₂环; (2) 又若对任意非空集合XM,L_s(X)由幂等元生成, 且S是局部的左duo环, 则S_s是连续环.     

Effect of heat treatment on microstructures and properties of a novel Al-Zn-Mg-Cu alloy for oil drilling

In view of the special requirements for strength, heat resistance and corrosion resistance of Al-Zn-Mg-Cu alloy for oil drilling, the Al-6.2 Zn-2.5 Mg-1.6 Cu alloy was prepared by increasing Cu content on basis of Russian Series 1953 alloy. The effect of heat treatment on the microstructures and properties of the alloy was characterized by optical microscope(OM), scanning electron microscope(SEM) and transmission electron microscope(TEM), and investigated by tensile test at room temperature, thermal exposure test and corrosion test. The results show that the strength after T6 aging treatment exhibit a decrease trend as an increase of the solution temperature from465 °C to 480 °C. After the solution treated by the rate of 470 °C/1 h, second phases dissolve into the matrix very well and the strength property reaches optimum. The alloy has better comprehensive properties treated by a solution treatment of 470 °C/1 h and then followed by an aging treatment of 120 °C/24 h + 170 °C/1 h + 120 °C/24 h. Under the aging state, the precipitated phases inside the grains are suitable in size, while on the grain boundary distribute discontinuously and the precipitate-free zone is obvious. Besides, the alloy still maintain high tensile properties. The yield strength, tensile strength and elongation are 650 MPa, 686 MPa,12.0%, respectively. The yield strength retention after heat exposure is 92%. The alloy has good corrosion resistance and the exfoliation corrosion degree. The average corrosion rate in the H_2S and CO_2 environment is 0.0024 mm/a, which is far less than the required 0.12 mm/a. It is insensitive to H_2S and CO_2 environments.     

Implicational lattices and generalization of Stone’s representation theorem

Let F(S) be the free algebra of type (,∨,→) generated by the non_empty set S, it is proved that the logical equivalent relation defined by means of R 0_semantics is a congruence relation on F(S) and the corresponding quotient algebra is said to be the R 0_semantic Lindenbaum algebra. Taking R 0_semantic Lindenbaum algebra as a prototype, the concepts of implicational lattices and regular implicational lattices which are generalizations of the concept of Boolean algebras are introduced. Besides, the concept of fuzzy implicational spaces is introduced and the representation theorem of regular implicational lattices is obtained by means of fuzzy implicational spaces. In case of Boolean algebras, the corresponding fuzzy implicational spaces are zero_dimensional compact Hausdorff spaces and herefrom it is proved that the famous Stone's representation theorem of Boolean algebras is a corollary of the representation theorem of regular implicational lattices.     

齐次Morrey-Herz空间上粗糙核分数次积分交换子及多线性算子的CBMO估计

利用齐次Morrey-Herz空间MK^α,λ_p,q(Rⁿ)与齐次Herz空间K^α,p_q(Rⁿ)之间的关系, 推广了K^α,p_q(Rⁿ)上的一些结果, 在 MK^α,λ_p,q(Rⁿ)上建立了具有粗糙核的分数次积分交换子T^b_Ω,l及多线性分数次积分算子T^A_Ω,l的中心有界平均振荡函数空间(CBMO)估计, 并得到了分数次极大交换子M^b_Ω,l和多线性分数次极大算子M^A_Ω,l的相应结果.     

C-H···Pd(II) interaction-driven homochiral M helix formation of neutral (R,R)-bis(pyrrol-2-ylmethyl- eneamino) cyclohexane palladium(II) complex

A chiral complex of (R,R)-Pd was prepared by reaction of optically pure (R,R)-bis(pyrrol-2-ylmethyl-eneamino) cyclohexane ligand with Pd(OAc)2·2H2O under the base condition at room temperature. The weak intermolecular C-H···Pd interaction was found to be responsible for the homochiral M helix for-mation of the neutral,chiral,mononuclear (R,R)-Pd in the crystal packing.     

逆半群上的几类模糊子半群

利用集合上模糊同余关系, 在逆半群上定义了模糊正规子半群和模糊商子半群, 并研究了逆半群上由这几类模糊关系所定义的模糊同余关系的一些性质. 通过模糊同余关系β, 得到模糊正规商子半群R及S/ρ上的模糊同余关系μ_R.     

电性距离矢量预测有机污染物的生物富集因子

以电性距离矢量Mt表征165种非离子性有机物(NOC)的分子结构.利用多元回归方法建立了122种NOC的生物富集因子(lg BCF)与32个Mt的数学模型,其相关系数R为0.976.经逐步回归建立最佳四变量(M15,M17,M36,M91)模型,其R为0.960;并以Jackknife法检验,其LOO交互检验系数(q2)为0.915.这4个Mt参数揭示了影响NOC生物富集因子的主要因素,结果表明该模型具有良好的估算能力与鲁棒性.以111个NOC为训练集的生物富集模型作用于11个NOC的检验集,显示出良好的预测能力.     

环A+xB［［x］］的S-Noether性质

设A⊆B是具有单位元的交换环的扩环, x是环B上的未定元, R:=A+xB［［ x］］, S是环A的一个乘性子集。证明了若S是A的非零因子的乘性子集且对任意的s∈S,(∩sⁿA,n≥1)∩S≠Ф,则R是S-Noether环当且仅当A是S-Noether环, B是S-有限A-模。
                   

Effect of KBr on the micellar properties of CTAB

The effect of KBr on the size, shape and microviscosity of CTAB micelles has been investigated by means of laser light scattering (LLS),¹H NMR measurements and fluorescence probe. The data obtained from the various techniques are quantitatively in agreement. The R_h of micelles in 0.01 rnol · L⁻¹ CTAB solution increases from 3.5 nm to 43 nm andR _g increases to 89 nm with addition of KBr salt. In this process, both the microviscosity and molecular weight of micelles M_w have noticeable increases, too. The rod-like micelles are formed at 0.1 rnol · L¹ KBr and the worm-like micelles are formed at above 0.2 rnol · L^-1 KBr.