用T621A石墨炭源合成出高强度金刚石

介绍了合成高强度(22．5kg～25．8kg)粗颗粒(40／50～25／30)单晶金刚石所需的炭源材料，触媒合金种类、装填方式、合成参数与合成效果。讨论了原料、合成工艺条件对生长高强度粗颗粒的优质金刚石的影响及合成机理。     

陶瓷压机预应力结构的分析

对大型液压自动压砖机的预应力结构进行了分析，建立了机架预紧的力学模型，给出了预紧力的计算公式，分析了预应力对结构疲劳强度的影响。最后通过设计实例证明了预应力结构是可靠的。     

高灵敏度弱磁传感器研究

磁传感器在生物医学、资源探测和航空航天等领域有巨大的应用价值,基于原子自旋的弱磁传感器拥有目前最高的磁场测量灵敏度。但通常的方案采用射频场调制或远离共振的激光检测,前者增加了磁力仪的线宽,而后者对激光频率的锁定带来了困难。为了解决以上问题,提出了一种基于激光强度调制和圆二向色性检测的原子弱磁传感器方案,详细描述了其工作原理和系统构成,并对原子弱磁传感器的性能进行了测试。实验结果表明:原子弱磁传感器的磁共振线宽为22 Hz,在对恒定磁场进行30 min连续测量时,峰峰值抖动小于9 pT,灵敏度达到了0.12 pT/Hz1/2。     

原子磁强计检测光闭环稳定系统设计

SERF态原子磁强计已实现人类历史上最高的0.16fT/Hz1/2的灵敏度。其检测方法主要是法拉第调制法。但法拉第调制法中光电流摄动或环境温度变化等干扰导致的检测光强的起伏会造成检测结果的不准确。为抑制检测光强起伏,设计了闭环原子磁强计检测光稳定系统。在法拉第调制法的基础上,增加了光路子系统和控制子系统对检测光强进行闭环稳定控制。通过对随机干扰进行闭环控制仿真与实验,验证本系统可以有效抑制各种干扰引起的光强起伏,使系统抗干扰能力提高1.2%,从而提高原子磁强计的检测精度。     

基于RBFNN的硫熏强度软测量建模

硫熏强度是亚法糖厂澄清工段非常重要的一个工艺指标,硫熏强度过低会影响澄清效果,过高会造成成品糖二氧化硫残留过高。由于目前尚缺乏合适的硫熏强度在线测试仪,人工化验滞后时间较长,难以根据该指标及时指导生产。为此,提出了一种基于糖厂澄清过程大量离/在线历史数据的硫熏强度软测量方法,分别建立基于径向基函数神经网络(RBFNN)、BP神经网络方法和广义动态模糊神经网络(GDFNN)的硫熏强度软测量模型。通过对模型的性能进行对比分析,说明了基于RBFNN硫熏强度软测量模型的优越性。     

管式振荡流反应器的流动模式研究 (II)高振荡强度下的流动模型和模拟

根据高振荡强度下的粒子成像流场可视化实验结果,在分析振荡流场中漩涡结构特征的基础上,提出用带有二次流区的全混腔室和室间返混的多釜串联模型来表征高振荡强度下的管式振荡流反应器流动特性。根据停留时间分布实验结果,运用小生境遗传算法优化求解模型参数与振荡参数之间的定量关系。模拟计算表明,优化后的模型给出的停留时间分布曲线与实验结果吻合良好。     

基于GIS技术的农村非点源污染分析——以渠县境内巴河州河汇流断面上游区域为例

为了有效地分析巴河州河汇合口(渠县境内)以上流域非点源污染问题,应用GIS技术进行水文分析(水系提取、流域划分)以及污染源的空间分异分析。基于评估区的水环境污染现状,选取城镇居民生活污水、农村居民生活污水、城镇地表径流、集中式畜禽养殖、化肥污染五大污染源,采用源强系数法和输出系数法进行COD、TN、TP 3种污染物的流失量计算,并分析其污染负荷,。结果表明:(1)评估区的91.93%的负荷来源于为农村居民生活污水、化肥污染、和城镇居民生活污水,最主要的污染源为农村居民生活污水。(2)评估区重点治理乡镇为三汇镇。研究成果较为清晰地分析出研究区非点源污染的分布情况,指出了需要重点治理的地域和污染源。     

用唐钢石人沟铁精矿生产超级精矿

以石人沟铁矿精矿粉为原料生产超级铁精矿，进行了磨矿—反浮选、分级—反浮选和分级—低磁场磁选等试验，并按磨矿—反浮选方案建成了生产超级铁精矿的选矿厂。实践证明阳离子反浮选是生产低硅高纯铁精矿的可靠工艺。     

Numerical study of particle dispersion in the wake of gas-particle flows past a circular cylinder using discrete vortex method

A numerical investigation on the particle dispersion in the wake of particle-laden gas flows past a circular cylinder at Reynolds number of 10⁵ is presented. In the numerical method, the Discrete Vortex Method with the diffusion velocity model is employed to calculate the unsteady gas flow fields and a Lagrangian approach is applied to track individual particles. A dispersion function is defined to represent the dispersion scale of the particle. The distributions of gas velocities and vortex blobs, the trajectories and dispersion functions as well as distributions for particles with various Stokes numbers ranging from 0.01 to 1000 are obtained. The numerical results show that: (1) very small sized particles with St = 0.01 can distribute both in the vortex core and around the vortex periphery, whereas intermediate sized particles with St = 1.0, 10 are distributed around the vortex periphery, and very large sized particles with St = 1000 do not feel the gas flow; (2) only at small Stokes number (St = 0.01, 0.1) the particles do not impact with the cylinder; (3) the particle's dispersion intensity decreases precipitously as St is increased from 0.01 to 10.     

A STUDY OF SILICONE OIL-IN-WATER EMULSIONS

Emulsions of silicone oil-in water were formed using a Brinkmann Polytron homogenizer with Igepal CO-530 as an emulsifier. Silicone viscosities ranged from 10 to 33,000 mPa.s at 25°C. Rheological characteristics and particle size analyses of silicone oil-in-water emulsions were studied. At high volume fraction of the dispersed phase (70%-75%), silicone oil-in-water emulsions were stable. At lower volume fractions (50%-60%), emulsions formed were less stable and the two phases easily separated in a few days. The emulsions formed with high volume fraction silicone oil show highly non-Newtonian behavior (shear thinning). Emulsions made with low viscosity oils had lower viscosities than those made from high viscosity oils. Relative viscosity-concentration data could be correlated by the Frankel and Acrivos Equation. Increasing the emulsifier concentration of 70% oil-in-water emulsions resulted in a decrease in mean droplet size and an increase in emulsion viscosity. Increasing the intensity of agitation also resulted in higher viscosity and smaller droplet size until a critical energy input above which droplet size increased. Emulsification with low shear mixing provides more control in decreasing mean droplet size with time.