磁性靶向药物递送中铁磁流体的动力学建模

在所有人体内进行的药物递送技术中,磁性药物靶向递送治疗由于其非入侵性和高靶向性而成为主要的方法．磁性药物靶向递送是将药物装载到磁性纳米颗粒上,利用外部磁场使其移动并聚焦在靶部位的方法．该法能提高靶部位药物的浓度,降低药物对正常组织的毒副作用．尽管已经有不少磁性靶向药物递送的理论分析,但是很少有人研究磁流体在血管里的流体动力学模型．该文提出了一个数学模型来描述作为药物载体的铁磁流体在外磁场作用下,在血管里的流体动力学特性,并在模型中增加了磁场力以及由此产生的不对称应力,增加了磁性纳米颗粒在磁场作用下的角动量方程．由于运动方程的数学复杂性,通过保留数学模型里物理特性最显著项来获得工程近似．用计算流体力学（CFD）进行数值仿真,分析了铁磁流体在一个模拟动脉瘤血管的三维管道里的流动状况,来进一步理解铁磁流体的临床应用．仿真结果和动物实验相一致．分析结果对于磁性靶向药物递送的各种应用提供了可参考的数据．     

Kinetics of Catalysis-Driven Aggregation Processes with Sequential Input of Catalyst

We investigate the kinetic behavior of a two-species catalysis-driven aggregation model, in which coagulation of species A occurs only with the help of species B. We suppose the monomers of species B are stable and cannot selfcoagulate in reaction processes. Meanwhile, the monomers are continuously injected into the system. The model with a constant rate kernel is investigated by means of the mean-field rate equation. We show that the Mneties of the system depends crucially on the details of the input term. The injection rate of species B is assumed to take the given time- dependent form K（t） -t^λ, and the sealing solution of the duster size distribution is then investigated analytically. It is found that the cluster size distribution can satisfy the conventional or modified scaling form in most cases.     

General Solutions of Reflection Equations for Bariev Model

The integrable general open-boundary conditions for the one-dimensional Bariev chain are considered. All kinds of solutions to the reflection equation （RE） and its dual are obtained.     

Competition Between Self-birth and Catalyzed Death in Aggregation Growth with Catalysis Injection

We propose two irreversible aggregation growth models of aggregates of two distinct species (A and B) to study the interactions between virus aggregates and medicine efficacy aggregates in the virus-medicine cooperative evolution system. The A-species aggregates evolve driven by self monomer birth andB-species aggregate-catalyzed monomer death in model I and by self birth, catalyzed death, and self monomer exchange reactions in model II, while the catalyst B-species aggregates are assumed to be injected into the system sustainedly or at a periodic time-dependent rate. The kinetic behaviors of the A-species aggregates are investigated by the rate equation approach based on the mean-field theory with the self birth rate kernel I_A(K)=Ik, catalyzed death rate kernel J_AB(k)=Jk and self exchange rate kernel K_A(k,l)=Kkl. The kinetic behaviors of the A-species aggregates are mainly dominated by the competition between the two effects of the self birth (with the effective rate I) and the catalyzed death (with the effective rate JB₀), while the effects of the self exchanges of the A-species aggregates which appear in an effectiverate KA₀ play important roles in the cases of I>JB₀ and I=JB₀. The evolution behaviors of the total mass M^A(t)₁ and the total aggregate number M^A(t)₀ are obtained, and the aggregate size distribution a_k(t) of species A is found toapproach a generalized scaling form in the case of I ≧ JB₀ and a special modified scaling form in the case of I0. The periodical evolution of the B-monomers concentration plays an exponential form of the periodic modulation.     

交联聚苯乙烯-丁二烯-苯乙烯双极膜的制备及其在电合成环氧丁二酸中的应用

以聚苯乙烯-丁二烯-苯乙烯（SBS）嵌段共聚物作为基膜材料,采用自由基接枝聚合反应,在SBS主链上引入丙烯酸（AA）、苯乙烯磺酸和γ-甲基丙烯酰氧基丙基三甲氧基硅烷（KH570）链段作为阳离子交换膜;引入丙烯酸二甲基胺基乙酯和KH570链段作阴离子交换膜,阴、阳离子交换膜经KH570结构中三甲氧基硅烷基团的水解缩合,得到含硅氧交联网的SBS接枝离子交换膜,用流延法制备了SBS双极膜。 测得SBS阴膜和阳膜的吸水率分别为63.9%和72.8%,SBS阴膜和阳膜的离子交换容量分别为1.51和2.71 mmol/g。 将SBS双极膜作为阴阳两室隔膜,采用钨酸钠/过钨酸钠体系由阴极间接电氧化合成了环氧丁二酸。 结果表明,以石墨为阴、阳电极,电流密度为2.0×10-2 A/cm²、50 ℃反应4 h,环氧丁二酸的产率为53.0%,电流效率为40.8%。     

Cluster Growth Through Monomer Adsorption Processes

We propose a monomer adsorption model, in which only the monomers are allowed to diffuse and adsorb onto other clusters. By means of the generalized rate equation we investigate the kinetic behavior of the system with a special rate kernel. For the system without monomer input, the concentration aj（t） of the Aj clusters （j 〉 1） asymptotically retains a nonzero quantity, while for the system with monomer input, it decays with time and vanishes finally. We also investigate the kinetics of an interesting model with fixed-rate monomer adsorption. For the ease without monomer source, the evolution of the system will halt at a finite time; while the system evolves infinitely in time in the case with monomer source. Finally, we also suggest a connection between the fixed-rate monomer adsorption systems and growing networks.     

在镉盐胁迫下扇贝鳃组织应激蛋白的研究

采用透射电子显微镜观察了虾夷盘扇贝(Patinopecten yessoensis)鳃组织细胞的超微结构, 发现镉盐能胁迫鳃组织中的腮丝、细胞核和线粒体产生病变. 利用双向凝胶电泳(2D-PAGE)优化分离扇贝鳃组织的全蛋白, 获得约800个蛋白质斑点, 并筛选出37个由于镉盐胁迫而产生的差异蛋白质斑点. 选用基质辅助激光解吸离子化-飞行时间质谱(MALDI-TOF MS)技术和数据库检索鉴定差异蛋白, 结果发现7个与镉毒性密切相关的蛋白质, 即热休克蛋白70和β-淀粉酶等上调蛋白质及原肌球蛋白、肌动蛋白和钙活化核苷酸酶1等下调蛋白质. 此外, 还发现转录调节子Crp/Fnr家族为低表达蛋白质, 而ABC转运子为高表达蛋白质. 在这些差异蛋白中, 部分蛋白质适合作为连续监测流动海水中镉污染程度及评价其危害性的蛋白指示物.     

A Proton Beam Delivery System for Conformal Therapyand Intensity Modulated Therapy

A scattering proton beam delivery system for conformal therapy and intensity modulated therapy is described. The beam is laterally spread out by a dual-ring doublescattering system and collimated by a program-controlled multileaf collimator and patientspecific fixed collimators. The proton range is adjusted and modulated by a programcontrolled binary filter and ridge filters.     

Polymerization of Norbornene via an Iron-Based Complex/MAO Catalytic System

IntroductionOwing to the high thermal stability,low waterabsorption and excellent optical properties as wellas the utility in an elastomeric material forvibration and sound damping or in a soakingmaterial for oil spills[1— 4 ] ,the homopolymers andthe copolymers of norbornene have attracted aconsiderable attention.So far,a large number oftransition- metal compounds have been known tocatalyze the ring- opening olefin metathesispolymerization (ROMP) ,or the vinyl additionpolymerization (VAP) …     

釜内聚合法制备间规聚苯乙烯与聚丙烯共混复合材料

采用MgCl2 TiCl4 β 二酮 MAO催化体系合成间规聚苯乙烯 (sPS)与等规聚丙烯 (iPP)共混复合材料 .对催化剂的活性和共混复合材料的组成随Al∶Ti和聚合温度的变化进行了表征 ,催化剂的活性可达 1.5× 10 5gB[molTi·h]- 1 ,sPS的含量可控制在 5 5 %～ 82 % .采用示差量热扫描仪 (DSC)和扫描电镜 (SEM)对共混复合材料的热性能和微观结构进行了研究