Study of the Optimal Integrated Control of a Dengue Transmission Model北大核心CSCD

建立了一个登革热在蚊子和人之间传播的模型,引入了Wolbachia、自我保护和杀虫剂三种控制措施,分别从常数控制和时变控制两个方面进行探讨。首先,分析了常数控制对模型基本再生数的影响,研究发现:Wolbachia有助于减小基本再生数,且基本再生数与自我保护和杀虫剂呈负相关。其次,以使得感染数最少且实施成本最低为目标,使用Pontryagin极值原理讨论最优控制。最后,通过数值模拟展示了最优控制的效果。     

分裂的正则Hom-Leibniz-Rinehart代数

作为Hom-Leibniz代数胚的代数类比, 本文引入Hom-Leibniz-Rinehart代数的概念. 证明了分裂的正则Hom-Leibniz-Rinehart代数$L$写成$L=U+\sum_{\gamma}I_\gamma$, 其中$U$为极大交换子代数$H$的子空间和$I_\gamma$为$L$的理想, 若$[\gamma]\neq[d]$, 满足$[I_\gamma, I_d]=0$. 随后分别发展了分裂Hom-Leibniz-Rinehart代数的根和权的连通技术.最后研究了紧致的正则Hom-Leibniz-Rinehart代数的结构.     

Analogues of hadwiger's theorem in space ℝ n —Sufficient conditions for a convex domain to enclose another

We estimate the kinematic measure of one convex domain moving to another under the groupG of rigid motions in ⁿ . We first estimate the kinematic formula for the total scalar curvature D ₀gD ₁ Rdv of then–2 dimensional intersection submanifold D ₀gD ₁. Then we use Chern and Yen's kinematic fundamental formula and our integral inequality to obtain a sufficient condition for one convex domain to contain another in ⁿ (4). Forn=4, we directly obtain another sufficient condition in ⁴.     

[Co(ptma)(amp)Cl]2+体系的一反式经式异构体(m3[ZnCl4]·0.5H2O)的晶体结构

在合成[Co(bpma)(tn)Cl]²⁺体系配合物的实验中,得到[Co(ptma)(amp)Cl]²⁺体系的一反式(ptma中仲胺上的氢相对于Cl)经式异构体(m3[ZnCl₄]·0.5H₂O),其中bpma=N,N′-二(2-吡啶基甲基)胺,tn=1,3丙二胺,ptma=N-(2-吡啶基甲基)丙二胺,amp=2-(氨基甲基)吡啶。此配合物异构体构型选择性形成的原因可能主要是其结构中配体间C-H…π相互作用使之更稳定的结果。利用单晶X-射线衍射法测定的晶体学参数:单斜晶系,空间群C2/c,a=1.55978(19)nm,b=1.33324(16)nm,c=2.2077(3)nm,β=94.832(3)°,V=4.5748(10)nm³,D_c=1.696g·cm^-3,Z=8,F₀₀₀=2360,μ(MoKα)=23.72cm^-1,R=0.0475,R_w=0.1204。配合物离子中Co³⁺为六配位。晶胞中含8个配合物阳离子,8个[ZnCl₄]^2-阴离子及4个水分子,对映体的比例为1∶1。     

沙蚕毒系化合物的结构与生物活性关系

用ＭＮＤＯ－ＰＭ３方法对沙蚕毒系化合物二氢沙蚕毒，硫氰酸酯，巴丹，杀虫单及其异构件的几何构型进行了全自由度优化，并计算了其电子结构，讨论了生物活性与几何构型和电了结构的关系。     

Indium-mediated Facile Synthesis of （6-Chloropyridine-3-yl）methyl Heterocyclic Thioether Derivatives in Aqueous Media

A series of substituted (6-chloropyridine-3-yl)methyl heterocyclic thioether derivatives were prepared by indium mediating in water. The preliminary biological tests showed that compound 3d exhibited good antiviral activity.     

层状LiMnO2的固相合成及电化学性能

以Mn₂O₃和氢氧化锂为原料，通过焙烧合成出o-LiMnO₂。用X射线衍射和扫描电镜对不同温度下合成的粉末样品进行了表征，并研究了材料的电化学性能。通过对不同温度条件下烧结样品的晶胞参数、布拉格(110)晶面峰半高宽及电化学性能研究发现：600 ℃下合成样品的半高宽最大，堆垛层错率高，同时电化学性能也最好，首次放电容量达到156 mAh·g^-1，20次循环后仍保持在140 mAh·g^-1以上。中高温固相合成的o-LiMnO₂材料，在晶粒范围大小相近时，材料电化学性能与材料堆垛层错率相关。     

Fused multifunctionalized bridge aromatic hydrocarbons from in situ-generated arynes and anthracene derivatives

This study presents a facile strategy for the formation of highly substituted butterfly 1,4-adducts/9,10-adducts via the Diels–Alder reaction of benzyne intermediates. The method achieves very good to excellent yields of the respective anthracene derivatives under mild conditions. This practical protocol is compatible with a variety of sensitive functional groups and provides access to difunctionalized bridge 1,4-adducts/9,10-adducts.     

BINOL双酰胺绿色催化吲哚与硝基烯烃的 Friedel-Crafts烷基化反应

合成了3种BINOL双酰胺(Ⅰ~Ⅲ)，其结构经¹H NMR, ¹³C NMR, HR-MS(ESI)和元素分析确证。研究了I~III对取代吲哚和硝基烯烃的Friedel-Crafts烷基化反应的催化性能，并对反应条件进行了优化。结果表明：在最优条件(CH₂Cl₂为溶剂，Ⅰ为催化剂，于40 ℃反应12 h)下，吲哚及取代吲哚与硝基烯烃均能有效的进行Friedel-Crafts烷基化反应，收率和ee值最高可达88%和90%。     

Magnetic properties of dendritic polycarbenes substituted by bulky peripheral groups

As photo-reactive precursors of high-spin organic compounds sterically separated from surroundings by bulky peripheral groups, diphenyldiazomethane derivatives substituted by tetrakis{3,5-bis(benzyloxy)benzyloxy} groups 1, by tetrakis[3,5-bis{3′,5′-bis(benzyloxy)benzyloxy}bezyloxy] groups 2, and nonakisdiazo compound associated with ferromagnetic spin couplers substituted by dodecakis{3,5-bis(benzyloxy)benzyloxy} groups 3, were prepared and their magnetic properties after irradiation in their own condensed films were investigated. Field dependences of magnetization and temperature dependences of χT value after irradiation of 1 and 2 clearly exhibited that spin centers i.e., diphenylcarbene parts of 1 and 2 were magnetically isolated from surrounding molecules each other by steric hindrance of the peripheral bulk substituents even in the neat films. In the case of 3, some part of molecules interacted antiferromagnetically with neighboring molecules but a fatal strong antiferromagnetic interaction was also avoided.