Synthesis,characterization, and biological activity of [2‐oxo‐2‐(4‐acetyl) phenyl amino] ethylene methacrylate and its derivatives

A new type of methacrylate monomer, [2‐oxo‐2‐(4‐acetyl) phenyl amino] ethylene methacrylate (APEMA), was synthesized. The oxime, 2,4‐dinitrophenylhydrazone, and thiosemicarbazone derivatives of poly{[2‐oxo‐2‐(4‐acetyl) phenyl amino] ethylene methacrylate} [poly(APEMA)] were prepared with hydroxylamine hydrochloride, 2,4‐dinitrophenylhydrazine, and thiosemicarbazone hydrochloride, respectively. The radical homopolymerization of APEMA was performed at 65 °C in a 1,4‐dioxane solution with benzoyl peroxide as an initiator. The monomer and its homopolymer were characterized with Fourier transform infrared and NMR techniques. The thermal stabilities of poly(APEMA) and its derivatives were investigated with thermogravimetric analysis and differential scanning calorimetry. The ultraviolet stability of the polymers were compared. The solubility and inherent viscosity of the polymers were also determined. The number‐average and weight‐average molecular weights and polydispersity index of the polymers were determined with gel permeation chromatography. The antibacterial and antifungal effects of the monomer and the polymer and its derivatives were also investigated on various bacteria and fungi. The activation energies of the thermal degradation of the polymers were calculated with the Ozawa method. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3157–3169, 2004     

Thermodynamic derivative properties and densities for hyperbaric gas condensates: SRK equation of state predictions versus Monte Carlo data

The ability of Soave–Redlich–Kwong cubic equation of state (SRK EoS) to predict densities and thermodynamic derivative properties such as thermal expansivity, isothermal compressibility, calorific capacity, and Joule–Thompson coefficients, for two gas condensates over a wide range of pressures (up to 110 MPa) was studied. The predictions of the EoS were compared to Monte Carlo simulation data obtained by Lagache et al. [M.H. Lagache, P. Ungerer, A. Boutin, Fluid Phase Equilibr. 220 (2004) 221]. Two completely different alpha functions for the SRK EoS attractive term were used and their respective effects on the predictions of such properties were analyzed. Also, two different forms of the crossed terms of the attractive parameter, a_ij, and three expressions of the crossed terms of the repulsive parameter, b_ij, were combined in different ways, and predictions were carried out. Little sensitivity of the properties on the chosen alpha function, except for the calorific capacities, was found in the systems studied. The most commonly used combination rules to model phase behavior of reservoir fluids, i.e. geometric and arithmetic forms of a_ij and b_ij, respectively, predicted very deficient results for these fluids at extreme conditions, specially for density calculations.     

Latex particles bearing hydrophilic grafted hairs with controlled chain length and functionality synthesized by reversible addition–fragmentation chain transfer

A method is described for synthesizing latex particles with anchored hairs by the grafting of hydrophilic chains, synthesized by reversible addition–fragmentation chain transfer, onto functionalized latex particles. These have the potential to bind biologically active species. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 1188–1195, 2003     

Group classification of unsteady boundary layer equations of a class of non-Newtonian fluids

Two dimensional unsteady boundary layer equations of a general model of non-Newtonian fluids were investigated in this study. In this model, the shear stress is taken as an arbitrary function of the velocity gradient. Group classification of the equations with respect to shear stress is done using two different approaches: (1) classical theory (2) equivalence transformations. Both approaches yield identical results. It is found that the principle Lie Algebra extends only for cases of Newtonian and Power-Law flows.     

Mathematical and numerical analysis of a simplified time-dependent viscoelastic flow

A time-dependent model corresponding to an Oldroyd-B viscoelastic fluid is considered, the convective terms being disregarded. Global existence in time is proved in Banach spaces provided the data are small enough, using the implicit function theorem and a maximum regularity property for a three fields Stokes problem. A finite element discretization in space is then proposed. Existence of the numerical solution is proved for small data, so as a priori error estimates, using again an implicit function theorem. Supported by the Swiss National Science Foundation. Fellowship PBEL2–114311.     

重离子治疗计划系统的构想

对重离子柬治癌的优势进行简要的回顾，并着重介绍了用于重离子放射治疗的治疗计划系统。治疗计划系统是一套软件系统，不同的硬件设施应有与其相匹配的软件系统，即治疗计划系统。在此基础上，针对兰州重离子加速器的特点提出一些关于治疗计划系统方面的构想。After a brief review concerning the advantages of heavy ions in radiotherapy, more interests are concentrated on treatment planning system （TPS） for heavy ion radiotherapy. Compared to the hardware devices such as accelerator and beam delivery system, the TPS is a set of software system, and different therapy facilities require their corresponding TPSs. Based on the specialities of the Heavy Ion Research Facility in Lanzhou （HIIRFL）, some suggestions on the TPS for tumor therapy at HIRFL finally are given.     

拟南芥胚的不同区域对MeV离子辐照的响应

利用不同能量的质子在大气环境中辐照拟南芥的含水种子，能量从1.1MeV到6.5MeV.根据模拟计算结果，相应能量的离子对种子的损伤区域分别为胚的浅层、胚的一半和整个胚.本实验中，具有较高能量的质子可以完全均匀地作用于拟南芥生长、发育及遗传密切相关的胚茎端分生组织，而能量较低的质子则不能直接作用于茎端分生组织.实验所用质子注量范围为4×10⁹ions/cm²—1×10¹⁴ions/cm².实验结果显示，虽然拟南芥种子的发芽率和幼苗存活率随离子注量增加都呈现下降的趋势，但对应于不同的胚损伤区域，即在不同的入射质子能量条件下，注量曲线具有各自的特征.实验结果显示，拟南芥种子中除了胚茎端分生组织作为对离子辐照敏感的辐射主靶外，茎端分生组织之外的胚区域可能作为离子辐射次靶，影响到最终的辐射生物学效应. 关键词： 离子辐照 拟南芥 胚区域 生物效应     

OPTIMAL INSTAR PARASITIZATION IN A STAGE STRUCTURED HOST-PARASITOID MODEL

A stage structured host-parasitoid model is derived and the equilibria studied. It is shown under what conditions the parasitoid controls an exponentially growing host in the sense that a coexistence equilibrium exists. Furthermore, for host populations whose inherent growth rate is not too large it is proved that in order to minimize the adult host equilibrium level it is necessary that the parasitoids attack only one of the larval stages. It is also proved in this case that the minimum adult host equilibrium level is attained when the parasitoids attack that larval stage which also maximizes the expected number of emerging adult parasitoid per larva at equilibrium. Numerical simulations tentatively indicate that the first conclusion remains in general valid for the model. However, numerical studies also show that it is not true in general that the optimal strategy will maximize the number of emerging adult parasitoid per larva at equilibrium.