简单图(p≤6)的伴随多项式

根据伴随多项式的基本性质，本文求出了顶点不大于6的简单图的伴随多项式。     

局部幂零条件下的S*(p)-群的幂零性

在局部幂零条件下研究了S*(p)-群,得到了S*(p)-群的幂零性.     

乙交酯丙交酯共聚物电纺丝超细纤维对利福平的控制释放

载药电纺丝超细纤维体系是药物控制释放领域中一个全新的剂型,近年来已引起广泛的关注.研究了乙交酯丙交酯共聚物(PLGA,LA/GA=80/20)电纺丝超细纤维在磷酸盐缓冲液(pH=7.4)中对利福平的控制释放行为.结果显示利福平的释放过程可分为2个阶段:在第一阶段为释放慢速期,药物的释放速率取决于纤维中利福平分子的扩散速...     

Release of dioctyl phthalate (DOP) from polyvinyl chloride (PVC) in apple packaging

The release of dioctyl phthalates (DOP) from polyvinyl chloride (PVC) in apples packaging has been investigated by using a high performance liquid chromatography (HPLC) during the storage. The results indicated that the release amount of DOP increased with time at the room temperature and the amount of DOP transported to the apples reached to 7.5 μg/g after 75 days of storage. Over the total amount of DOP transferred to apples, however, about 6.56 μg/g DOP was retained in the cuticle and only 1.37 μg/g DOP reached the apple flesh.     

(+)-4S,6R-对-(艹孟)-1-烯-6,8-二醇的简便合成

 以α-蒎烯为原料,脂环酸钴作为催化剂,通入氧气,控制反应温度在80~90℃的条件下,意外地得到无色针状结晶化合物(+)—4S,6R-对-(艹孟)-1-烯-6,8-二醇,反应产率为6.6%,ee值为98.9%.经旋光仪测定,其旋光方向为右旋,其结构分别由IR,¹HNMR,¹CNMR,¹³C-¹H-HMQC-2DNMR及MS波谱图的验证.     

反应动力学拆分法合成(2S,4R)和(2S,4S)-6-庚烯-2,4-二醇

本研究以手性(S)-3-羟基-丁酸甲酯为原料,经TBSCl保护羟基、DIBAL-H还原及烯丙基锌试剂反应后合成(2S,4R/S)-6-庚烯-2,4-二醇中间体,利用anti/syn-1,3-二醇在进行丙酮叉保护以及脱丙酮叉保护时反应动力学性能上的差异,并通过高立体选择性的动力学拆分法合成出目标产物(2S,4S)和(2S,4R)-6-庚烯-2,4-二醇.     

吉首大学学报(自然科学版)2006年度第26卷第1~6期(卷终)总目次

题名作者期号页号带抛物退化线的二阶混合型方程的间断斜微商……………………………………………闻国椿1(1)群论的一个整除问题…………………………………………………………………………乐茂华1(8)具限制系数广义多项式集的最佳同时逼近特征……………………………………………罗先发1(9)DirichletL-函数的一个k次均值分布公式…………………………………………………高丽1(17)理赔额受限下的风险过程…………………………………………………何树红,李如兵,董志伟1(19)不可分市场中一般均衡的一个充分条件…………………………………李…     

C60CH2和C60HR(R＝C6H5CO--)的光限幅特性

应用倍频Ｎｄ：ＹＡＧ激光研究了２种新合成的Ｃ６０衍生物Ｃ６０ＣＨ２和Ｃ６０ＨＲ（Ｒ＝Ｃ６Ｈ５ＣＯ－）甲苯溶液的光限幅性质。Ｃ６０ＨＲ的光限幅效应与Ｃ６０相比稍则Ｃ６０ＣＨ２的光限幅效应与Ｃ６０相近,并具有更低的限幅幅值。     

关于多级火箭的优化理论(27)

在这篇文章中,"关于多级火箭的优化理论(24)"一文中的一个结论被完善。     

S4+离子3s2-3s3p和S5+离子3s-3p电子碰撞激发截面

利用全相对论扭曲波电子碰撞激发计算程序REIE06,系统计算了阈值附近不同入射电子能量下S~(4+)离子基态3s~(21)S_0到激发态3s3p ~3P_(0,1,2)~1P_1和S~(5+)离子基态3s ~2S_(1/2)到激发态3p ~2P_(1/2)~2P_(2/3)精细结构能级的碰撞截面,在两种关联模型下,分析了组态相互作用对碰撞截面的影响.目前的计算结果与Wallbank实验值~([14])相比,得到很好的一致性.     

Functional insights from the structure of the 30S ribosomal subunit and its interactions with antibiotics

The 30S ribosomal subunit has two primary functions in protein synthesis. It discriminates against aminoacyl transfer RNAs that do not match the codon of messenger RNA, thereby ensuring accuracy in translation of the genetic message in a process called decoding. Also, it works with the 50S subunit to move the tRNAs and associated mRNA by precisely one codon, in a process called translocation. Here we describe the functional implications of the high-resolution 30S crystal structure presented in the accompanying paper, and infer details of the interactions between the 30S subunit and its tRNA and mRNA ligands. We also describe the crystal structure of the 30S subunit complexed with the antibiotics paromomycin, streptomycin and spectinomycin, which interfere with decoding and translocation. This work reveals the structural basis for the action of these antibiotics, and leads to a model for the role of the universally conserved 16S RNA residues A1492 and A1493 in the decoding process.     

近K(a)hler球面S6中的全实环面

本文证明了两个定理，用近复结构来刻划平凡的极小环面。     

Release of somatostatin-28(1-12) from rat hypothalamus in vitro

Following the discovery of the growth hormone release-inhibiting factor somatostatin from extracts of ovine hypothalamus, an N-terminally extended somatostatin of 28 amino acids has been identified in mammalian tissue. The original peptide, somatostatin-14 (SS14), corresponds to the C-terminus of somatostatin-28 (SS28). Both SS28 and SS14 have biological activity, occur in several rat brain regions, are present in cell bodies and nerve terminals and can be released in vitro upon depolarization in a calcium-dependent manner. Further, high-affinity binding sites were described for SS14, which also bind SS28 (refs 20-23). Recently, a dodecapeptide which corresponds to the N-terminus of somatostatin-28, somatostatin-28(1-12), has been characterized in rat hypothalamus. Radioimmunological and immunohistochemical studies have indicated the presence of SS28(1-12)-like immunoreactivity in several cortical and subcortical regions of the rat brain. This peptide was found to be unevenly distributed with the highest concentration in the hypothalamus, and preferentially localized to dendritic and axonal processes and terminals. These observations suggest that SS28(1-12) may be a neurotransmitter. In this study, we describe a calcium-dependent release of a SS28(1-12)-like peptide from hypothalamic slices in vitro. This finding supports a neurotransmitter function for this peptide.     

不同诱导方式对6-methylsalicylic acid在酿酒酵母（S．cerevisiae）中表达的影响

聚酮类化合物（Polyketids,PKS）是自然界广泛存在的由真菌或放线菌等微生物产生的,具有一系列复杂结构的微生物次生代谢产物,其中很多种类已经被开发成为具有抗菌、抗癌、抗肿瘤活性的药物．来源于Penicillium patulum中的6-MSAS（6-methylsalicylic acid synthase）是为数不多的几类从基闪水平到合成酶体系都已被完全阐明的真菌类PKS种类之一．本研究通过对摇瓶发酵的突变型菌株（S．cerevisiae334）在表达过程中诱导剂添加的时间和剂量对6-MSA合成的影响进行分析,结果表明：除24h和48h之间没有差异之外,在其他不同的诱导时间之间均为极显著差异．其中24h时加入诱导剂可以获得最高的6-MSA合成产量,为104．51mg·L^-1,在不同的诱导剂剂量的处理中,不同诱导剂剂量对最终产物的表达产量有极显著差异．其中添加w=10％的β-半乳糖诱导获得了最高的表达产量,为121．61mg·L^-1,不同的诱导方式在组合会对6-MSA的表达产生极其显著的差异．     

覆盖矩阵P的(0,1)-矩阵类u_p(R,S)的结构

本文研究了覆盖矩阵P的(0,1)-矩阵类U_p(R,S)的结构,给出了U_p(R,S)中恒元的存在性定理.取P=0,即得Ryser关于U(R,S)中恒1的结果.     

围长至少为6的平面图的L(p,q)-标号

令λp,q(G)为图G的L(p,q)-标号数,其中p和q是正整数且p≥q.证明了若G是围长g(G)≥6的平面图,则λp,q(G)≤(2q- 1)△(G) +4p +6q-5;若G是围长g(G)≥6且△(G)≠5的平面图,则λp,q(G)≤(2q-1)△(G)+ 10p-2q-4.这一结果暗含着对于g(G)≥6且△(G)≠5的平面图G,Wegner的猜想成立.     

关于B-值Dirichlet级数(p,q)(R)级和(p,q)(R)型的系数重排

讨论了B-值Dirichlet级数的(p,q)(R)级及(p,q)(R)型的概念与性质。并由此得出了B-值Dirichlet级数的(p,q)(R)级及(p,q)(R)型经系数重排后保持不变的充分、必要条件。结果表明,带有(p,q)(R)级的B-值Dirichlet级数经一定条件下的系数重排后,保持原增长特性。