时变垂向入渗影响下河渠-潜水非稳定渗流模型的解及应用

在河渠边界控制下的半无限含水层中,对时变垂向入渗影响下的潜水非稳定渗流模型,利用Boussinesq第一线性化方法,通过Laplace变换并结合卷积原理,导出模型的解析解．根据不同水文地质条件下解的数学特征,建立相应的含水层参数求解方法;在此基础上,建立计算河渠与含水层之间水量交换的公式,以及计算潜水蒸发强度的递推公式．以安徽淮北平原某河流-潜水含水层系统为例,阐述上述方法的计算过程与步骤．     

Low Water Swelling and High Proton Conducting Sulfonated Poly(arylene ether) with Pendant Sulfoalkyl Groups for Proton Exchange Membranes

Novel side‐chain‐type sulfonated poly(arylene ether) with pendant sulfoalkyl group copolymers (PSA‐SPAE‐6F) have been synthesized by direct copolymerization from a new sulfonated monomer, sodium 3‐(4‐(2,6‐difluorobenzoyl)phenyl)propane‐1‐sulfonate. The sulfonate content could be easily controlled by adjusting the sulfonated and the unsulfonated monomer feed ratio. The obtained copolymers all show good thermal and mechanical properties. It should be noted that the most highly sulfonated copolymer, PSA‐SPAE‐6F90 with an ion exchange capacity of 1.30 mequiv · g⁻¹, shows a proton conductivity of 0.11 S · cm⁻¹ and a water swelling ratio of only 12.9% at 100 °C, which indicates its high proton conductivity and excellent dimensional stability in hot water.

     

Surface‐Functionalized,Ring‐Opening Metathesis Polymerization‐Derived Monoliths for Anion‐Exchange Chromatography

Ring‐opening metathesis polymerization (ROMP) was used for the synthesis of monolithic capillary columns with inner diameters of 200 µm. The resulting polymeric monoliths were characterized by inverse size‐exclusion chromatography (ISEC). Surface functionalization was carried out in situ using 2‐(N,N‐dimethylaminoethyl)norborn‐5‐ene‐2‐ylcarboxylic amide ( 1 ). The resulting functionalized monoliths were successfully used in anion‐exchange chromatography of oligodeoxynucleotides.

     

天然沸石粉阳离子吸附性能分析方法的探讨

通过比较不同浓度的NH4Ac溶液对天然沸石粉所吸附的碱金属和碱土金属离子多次连续提取的效果,将由交换性K^ 、Na^ 、Ca^2 和Mg^2 加和所获得的阳离子交换量与由常规土壤阳离子交换量测定法获得的阳离子交换量进行比较,发现常规的土壤分析方法不适于测定天然沸石粉所吸附的交换性K^ 、Na^ 、Ca^2 和Mg^2 及阳离子交换量。建议用K^ 、Na^ 、Ca^2 和Mg^2 5次提取总量分别作为天然沸石粉所吸附的交换性K^ 、Na^ 、Ca^2 和Mg^2 的估算值,并把其提取量加和作为沸石粉阳离子交换量的估算值．     

Purification of L-Lysine in Simulated Moving Bed and Fixed-Bed Chromatography

 L-Lysine was produced by a microbial process utilizing a Corynebacterium glutamicum (ATCC 21799) strain. L-Lysine was purified from the cultivated medium by fixed-bed and simulated moving bed （SMB） chromatography. The separation conditions including pH, eluent concentration and Lys+ and Lys2+ adsorption isotherms were studied in batch adsorption. The column capacity, eluent flow rate and eluent concentration have been studied in fixed-bed chromatography. Maximum purification rate of lysine was obtained as 0.066 g/(g·h) (per gram resin and per hour) at an eluent flow rate of 10 mL/min in fixed-bed chromatography. The results obtained from SMB were 0.11 g/(g·h) for L-lysine purification rate and 96% for L-lysine recovery.     

层状钠锰氧化物的制备及离子交换反应动力学

层状钠锰氧化物的制备及离子交换反应动力学     

Is there a Di-Ω State?

Resonating-group method has been applied to calculate the ΩΩ (SIJ=-6,0,0) dibaryon state in the framework of the extended quark-delocalization color-screening model. The mass of the di-Ω is predicted to be about 45 MeV lower than the Ω-Ω threshold. The effect of channel coupling due to the tensor force and sensitivity to meson exchange short-range cutoff radius, r₀ have also been studied.     

水平结晶法生长蓝宝石晶体的热交换研究

本文通过综合处理结晶设备内部(含有晶体的容器里)和外部(设备的工作空间:加热件和热绝缘)的热交换问题,给出了对不同类型结晶设备热系统的计算研究.数学模型计算的结果与用水平定向结晶设备生长蓝宝石板的实验作了比较,描述了实验发现的温场突变现象,并就水平定向生长蓝宝石晶体分析了它产生的可能原因.给出了模型准确性和应用范围的结论.     

热传导对气-液射流界面不稳定性的作用机理研究

研究了平面分层气-液射流在非线性温度分布条件下的界面不稳定性性质.考虑了气体的可压缩性、液体的粘性、以及气体热导率和密度随温度变化等事实.并应用正则模态方法将问题转化为四阶变系数常微分方程,用数值积分和多重打靶法对模型的空间模式进行了计算,研究了不稳定模态随各物理参量的变化趋势.计算表明模型所体现的不稳定性特征与其它模型的计算结果是一致的.同时计算还得出气体和液体的温差越小、雷诺数越大、热导率变大均将有利于液体射流有效雾化的结果.该结论与HJE.Co.Inc(Glens Falls,NY,USA)的实验数据是定性吻合的.     

不完全三值逻辑在语言表达上的相互比较

深入讨论各种命题联结词含量不完全的三值逻辑的语言表达的能力,完全弄明白了三值系统L3,L3,B3,B3,K3,K3,MP的语言表达能力的等效或不等效关系,特别应当指出的一个结论是：中介命题逻辑MP作为一种命题联结词含量不完全的三值系统而言,它和其他命题联结含量不完全的三值逻辑L3,L3Δ,B3,B3Δ,K3,K3Δ的语言表达能力都不等效,从而也由此体现出MP的一种自身特色。