反应扩散方程混合有限元的两层网格方法

考虑反应扩散方程的混合有限元求解方法.对方程通过先在粗网格上求解非线性问题,再在细网格上求解相应的线性问题,获得了两个两层网格算法.     

Molecular analysis of axonal target specificity and synapse formation

The development of neuronal connectivity requires the growth of axons to their target region and the formation of dendritic trees that extend into specific layers. Within the target region growth cones, the tips of extending axons are guided to finer target fields including specific subcellular compartments where they form synapses. In this article we highlight recent progress on molecular aspects of axonal subcellular target selection such as the axon initial segment or specific sublaminae of the vertebrate retina. We then discuss the very recent progress on the molecular analysis of synapse formation in the central nervous system, including the direction of differentiation into an inhibitory or excitatory synapse. Apparently, initial synaptic contacts are structurally and functionally modulated by neuronal activity, raising the question how neuronal activity can modify synaptic circuits. We therefore also focus on neural proteins that are up-regulated, secreted or converted by synaptic activity and, thus, might represent molecular candidates for experience-driven refinement or remodeling of synaptic connections. Received 5 July 2005; received after revision 19 August 2005; accepted 2 September 2005     

十五元[N4]大环铜配合物的合成、结构和性质

合成了水合十五元[N4]草酰胺大环铜配合物,即水合2,3-二氧-5,6,14,15-二苯基-1,4,8,12-四氮杂环十五-7,12-二烯铜配合物,研究了其晶体结构、红外光谱、电子顺磁谱性质,并利用电化学技术对其结构的稳定性进行了讨论。     

脉冲电压对GCr15轴承钢凝固组织的影响

首次在实验室条件下将电脉冲处理运用于GCr15 轴承钢凝固组织的研究,通过改变脉冲电压得到了枝晶显著细化的凝固组织,在一定程度上使GCr15轴承钢的珠光体发生粗化变化.并且对电脉冲细化金属的机理进行了探讨.     

15吨转炉优化炉容比设计与研究

介绍了15吨转炉优化炉容比改造与设计,熔容比得到改善,产量大幅度提高,平衡了公司钢铁料,连铸机能力得到发挥;各项经济指标有了进一步提高,金属喷溅减少,降低了钢铁料消耗,降低吹损率,冶炼周期缩短,钢的质量有所提高,炉壳变形小,托圈强度、耳轴强度设计能满足生产需求。     

苯并15冠5配合物:[Na(B15C5)·H2O]2 [Zn(NCS)4]的合成与晶体结构

合成了苯并15-冠-5(B15-C-5)的配合物[Na(B15C5)·H2O]2[Zn(NCS)4],通过元素分析、红外光谱、X-射线单晶结构衍射对配合物进行了表征.该配合物为单斜晶系,空间群C2/C,晶体学结构数据a=1.6924(5)nm,b=1.2998(4)nm,c=2.1483(4)nm,β=112.352(6)°,V=4.371(2)nm3,Z=4,Dc=1.389mg/m3,F(000)=1896,R1=0.0657,wR2=0.1783.结构分析表明Na+与B15-C-5分子中氧原子配位成键,阴离子为[Zn(NCS)4]2-具有四面体构型.两个[Na(B15C5)·H2O]+配阳离子与一个[Zn(NCS)4]2-配阴离子通过离子键形成中性配合物.     

P15基因甲基化和血液病相关性的研究进展（综述）

P15基因是肿瘤抑制基因的侯选基因,受细胞生长抑制蛋白TGF－β的诱导,编码周期素依赖激酶4／6（CDK4／6）抑制因子,对细胞周期起负调控作用,P15基因操纵区5′－GpG岛的甲基化被认为是基因缺失之外的又一失活机制。P15基因5′－Gp G岛的异常甲基化导致该基因转录的抑制,5′－杂氮脱氧胞嘧啶（5′－Aza-2cdR）通过共价俘获DNA甲基转移酶抑制DNA的甲基化,使因甲基化失活的生长调控基因重新激活并表达。5′－Aza-2cdR可通过P15基因去甲基化再表达抑制细胞的生长,为临床恶性白血液病去甲基化治疗提供实验依据。     

Biomimetic synthesis for precursor of muscone

Muscone is a precious fragrant compound scarce in nature. Many attempts have been made to synthesize this unique natural product. In this work, the one- carbon unit transfer reaction of tetrahydrofolate coenzyme was initiated. Benzimidazolium salt was used as the tetrahydrofolate coenzyme model at formic acid oxidation level and di-Grignard reagent as the nucleophile to which one-carbon unit was transferred; the biomimetic synthesis of 2,15- hexade-canedione, a precursor of muscone, was successfully accomplished by using the addition-hydrolysis reaction of benzimidazolium salt with Grignard reagent. And an important useful method for the synthesis of muscone is provided.     

可卡因与其降解抗体15A10的分子对接及分子动力学研究

可卡因是一种精神依赖性药物．它首先作用于大脑皮层使之兴奋,然后由过度兴奋转为抑制,可卡因最重要的作用是对中枢系统的刺激作用,可卡因中毒后,先是感到欣快,随后会出现情绪不安、恶心、呕吐等症状．严重者出现脉搏增快、血压增高和呼吸加快,可引起高血压及其各种合并症,导致室性纤颤、呼吸和循环系统衰竭而死亡。显然,发展一种合适的抑制剂去治疗可卡因的滥用和上瘾是十分困难的,因为可卡因本身就是一个抑制剂,这意味着要用一个毒性更高的抑制剂去抑制可卡因的作用,既然很难在中枢神经系统中设置一个阻碍可卡因的小分子,我们可以考虑在可卡因到达中枢神经系统之前将之降解,     

介孔材料SBA-15的功能修饰及其对水中铜离子的吸附

以三嵌段共聚物P123作为模板剂,采用水热法合成出具有规则孔道高度有序的介孔氧化硅材料SBA-15,利用3-巯丙基三甲氧基硅烷和3-氨基丙基三甲氧基硅烷分别对其进行功能化,成功引入对重金属离子有强吸附性能的巯基和氨基,使用XRD、SEM等测试手段对介孔材料进行了表征。吸附实验和Langmuir模型拟合结果表明,巯基和氨基SBA-15对铜离子的理论吸附量分别能达到1.10mmol/g和0.74mmol/g。