Particle circulation and oxygen mass transfer in an immobilized cell bioreactor

Two important considerations in the design of an aerobic particulate immobilized cell bioreactor are the provision of sufficient oxygen to maintain the desired metabolism of the immobilized organism, and the biomass holdup (which is proportional to the number of immobilized cell particles in the reactor). The Circulating Bed Reactor, a reactor developed for use with those forms of immobilization that result in particles of essentially neutral buoyancy, operates with an expanded bed of circulating particles. The particle number density attainable in such a reactor has been found to be dependent upon the circulation cell aspect ratio, the individual particle properties, the static bed voidage of the particles, and the superficial gas velocity. The oxygen mass transfer characteristics have been found to be dependent upon the circulatory nature of the system, the particle (solids) holdup, the particle porosity, and the superficial gas velocity.     

Ultracentrifugation Method to Measure Water-Soluble Monomer Incorporation in Latex

Emulsion copolymerizations involving water-soluble functional monomers such as N-methylolacrylamide often result in the formation of water-soluble polymer that remains in the aqueous phase of the latex. A simple procedure is developed to determine the amount of water-soluble polymer in the aqueous phase of a high-solids latex using ultracentrifugation. Dilution of the latex with water is usually found necessary for good separation during ultracentrifugation. If the latex contains a surface-active species (surfactant) in amounts comparable to the amount of water-soluble polymer, calculation of the amount of water-soluble polymer in the serum of the original latex will require information about dilution dependent partitioning of the surfactant between the surface of the particles and the aqueous phase. This paper outlines a procedure that enables determination of the amount of water-soluble polymer in the aqueous phase of the original latex, by ultracentrifugation of the latex diluted to different concentrations. The procedure also gives the Henrys constant for the adsorption of the surfactant on the surface of the polymer particles in the latex.     

壳聚糖在荔枝果汁研制上的应用研究

实验结果0.4g/L的壳聚糖对荔枝果汁絮凝沉降速度最快,对荔枝果汁具有很好的澄清效果;而且在脱色功能上也十分显著,色值可提高32.8%.同时壳聚糖对荔枝果汁的可溶性固形物含量不影响.在pH为3-4时,壳聚糖对荔枝果汁澄清与防腐具有很好的稳定性.     

Dynamical framework with blocking topography coordinates for atmospheric GCM and its validation

The dynamical framework with Blocking Topography Coordinates (hereafter, BTC), which is suited to handle the steep topography for the atmospheric general circulation models, is presented in this paper, together with its validation results. The integral properties of both the differential and finite-difference equations for the BTC dynamical core are: gross mass conservation, quadratic conservation for advection terms, Coriolis force does not change the kinetic energy, conservation of total available energy. The improved nonlinear iteration scheme is utilized for the time-integration. The energy conservation for BTC dynamical core is validated by using the integration results from 9-layer and 21-layer version respectively. Comparison results show that, the changes of the kinetic energy and total available potential energy during the integration are quite close for both the BTC dynamical framework and the dynamical framework of IAP 9-level and IAP 21-level AGCM, and this may suggest that the BTC dynamical core can be used for long-term integration with good computational stability. Furthermore, the BTC dynamical core has the advantage over the terrain following (sigma) coordinates in its better representation of the influence of the large-scale topography on the atmospheric general circulation. Finally, the correctness and reasonableness of the BTC dynamical core has been further proved by the numerical simulation of the topography influence on the quasi-stationary planetary wave with 21-layer version of BTC dynamical framework.     

构建图书馆流通管理现代化的新模式

结合实践对图书馆流通业务管理中的参数组合进行了详细的技术讨论和理性分析，指出通过灵活多样的参数设置，不同规模与类型的图书馆可以量身定制符合自身特色的流通业务管理模式，从而推动图书馆管理与业务工作现代化的创新。     

滚筒装煤时煤流循环系数的计算

分析了采煤机螺旋简装煤过程中煤流的循环现象，导出了循环煤量及循环系数的计算式，讨论了影响循环系数的几种重要因素。     

A local positive feedback of the tropical Pacific ocean-atmosphere system on interdecadal timescales

SINCE THE 1990S, THE CLIMATIC VARIABILITY ON INTERDE- CADAL TIME SCALES BECAME THE FOCUS OF THE INTERNATIONAL CLIMATOLOGY RESEARCH MISSIONS[1―3]. ON TIME SCALES OF A DECADE OR MORE, THE OCEAN CIRCULATION PREDOMINATEDHEAT BALANCE AND HYDROLOGICAL CYCLE, S…     

我国发展电子商务存在的问题和对策

电子商务是一个新兴的产业，在我国的发展存在一定的制约因素，本文讨论了影响我国电子商务发展的几个因素，并提出了解决的方法，为我国电子商务的发展提供借鉴．     

HMC工艺对选煤厂洗水闭路循环的影响

高效重介质旋流器分选(HMC)是煤炭深度降灰脱硫新技术.探讨采用HMC工艺后,磁选尾矿对介质再生、煤泥水沉降特性和絮凝剂选择的影响.研究表明磁尾与伴生粘土矿物的协同效应会改变粘土矿物和煤颗粒双电层的电动电位,对介质回收、煤泥水沉降产生负面影响.