悬浮类果品饮料稳定性问题的初步实验研究

悬浮类果品饮料如粒粒苹果、粒粒菠萝、各类果茶等,以其味道鲜美、营养丰富以及诱人的外观,很受广大消费者的喜爱,但其悬浮稳定性问题一直是许多类果品饮料生产的一个关键问题。以苹果粒悬浮饮料粒粒苹果为例,在实验基础上,详细地讨论了影响其悬浮稳定性的因素,提出了解决问题的方法和措施,供有关的生产和研究参考。     

热熔凝聚法加工农药悬浮剂研究

介绍了采用热熔凝聚法对加工二氯喹磷酸、氟虫睛、乙霉威悬浮剂的试验结果，并测定了制剂的粒度分布、冷贮、热贮稳定性等理化性质。该法工艺简单、加工方便、节省能源、工业上切实可行。     

一次风机节能改造

为解决一次风机出口风压低、火焰无力度、系统功耗高等问题,采用空气悬浮风机对其进行节能改造。拆除原有的一次风机备用风机,在原有底座上安装空气悬浮风机,整体设计安装悬浮风机出口管道。改造后,一次风机出口风压明显增大,煤粉燃烧充分,火焰调整灵活,每小时可节电30kWh,两处对空排放管道加装消声器,降噪效果显著。     

基于磁流变阻尼器的车辆悬架系统模糊半主动控制

在对磁流变液和磁流变阻尼器的研究基础上 ,以磁流变阻尼器作为半主动控制元件组成模糊半主动悬架系统。运用数值仿真和试验研究等方法对基于磁流变阻尼器的模糊半主动悬架进行了研究。数值仿真和试验结果表明 ,设计的模糊半主动控制算法可对基于磁流变阻尼器的半主动控制悬架实现有效的控制     

聚甲基丙烯酸甲酯／纳米SiO2复合粒子的制备与表征

采用甲基丙烯酸-3-甲氧基硅丙酯（MPs）对分散于甲基丙烯酸甲酯（MMA）中的纳米SiO2粒子进行偶联改性，得到了表面改性的纳米SiO2单体分散液，用原位悬浮聚合方法制备了不同SiO2含量的PMMA／纳米SiO2复合粒子。通过红外光谱、透射电镜、差示扫描量热分析和热重分析等方法对制备的纳米复合粒子进行了表征，结果表明，纳米SiO2粒子在PMMA中分散良好；MMA可通过与MPS的共聚而有效地接枝到SiO2粒子表面，当SiO2含量为6．6％（质量分数，下同）、MPS用量为0．06g／gSiO2时，其接枝率可达73．8％；同时，纳米SiO2的引入可提高PMMA的耐热性能，当Si02含量为14.7％时，其玻璃化转变温度和最大热分解速率时的温度分别提高了11．8℃和18．8℃。     

Optimising the dewatering behaviour of clay tailings through interfacial chemistry, orthokinetic flocculation and controlled shear

The effect of shear on dewatering behaviour and particle interactions of Na-exchanged smectite and kaolinite clay dispersions has been investigated at pH 7.5, using hydrolysable Ca(II) and Mn(II) ions as coagulants and high molecular weight anionic and non-ionic polyacrylamide (PAM A and PAM N, respectively) and polyethylene oxide (PEO) flocculants. Metal ion addition enhanced the flocculation performance by dramatically reducing the magnitude of the particle zeta potential and, in the case of smectite pulp, suppressing osmotic swelling. Under optimum orthokinetic flocculation conditions of controlled agitation rate and duration, PAM A and PEO-based flocs settled faster than those of PAM N whilst kaolinite pulps produced higher sedimentation rates than smectite pulps. The settling rates are nearly an order of magnitude greater than those observed under standard flocculant-pulp mixing/flocculation methods of inversion and plunging. The difference in the flocculant behaviour is attributed to the more expanded conformation of PAM A and PEO polymer chains in contrast to PAM N, whilst the lower yield stresses, reflecting inter-particle bridging and floc network structure strength that are conducive to faster clarification, were displayed by kaolinite pulps. Following shear, similar consolidation enhancement of ≈ 5-7 wt.% solid for both pulps was achieved at an optimum agitation range of 100-200 rpm. This was accompanied by decreased yield stress in the case of PAM A-based pulps, indicating non-reversible disruption of polymer mediated particle and floc network structure. In contrast, the yield stresses of PAM N and PEO flocculated dispersions indicated similar and stronger particle interactions, respectively, upon consolidation following shear. The findings show clear links between effect of shear, interfacial chemistry and polymer structure on pulp particle interactions and dewaterability.     

多菌灵·硫·三环唑混配对抑制水稻稻瘟病菌和纹枯病菌的协同增效作用

多菌灵、硫及三环唑混配成悬浮剂,对抑制稻瘟病菌的菌丝生长、分生孢子萌发、附着胞的形成、产孢能力及纹枯病菌菌丝生长等都具有较明显的协同增效作用,协同作用比率(SR)分别为1.64、5.58、4.30、1.81及1.73。混配剂集合了多菌灵、硫及三环唑的优点,并显示出耐雨水冲刷、持效期长的特点。田间试验亦表明其防病增产作用比较显著。     

The Yield Stress of Gas/Liquid/Fibre Suspensions

Yield stress measurements of gas/liquid/fibre suspensions, were conducted to examine the effect of gas concentration as well as fibre concentration. Obtaining a well mixed stable pulp suspension with gas was difficult. A transparent model system consisting of glass fibres submersed in refractive index matched liquid gave stable suspensions and had the additional advantage of allowing visual observations. The measurements were performed in a baffled shear tester and concentrations were in the range of 0–12.5% vol. gas and 8–14% wt. fibres. Results show that yield stress decreases with increasing gas fraction for constant fibre concentrations. Since the fibre concentration is defined in the liquid phase, the amount of fibres decreases with increasing gas concentration. This fact alone partly explains the decrease in yield stress, but the gas also has a direct impact on the decrease in yield stress. Further, as expected, the yield stress increases with increasing fibre concentrations when the gas fraction is kept constant.     

Discrete-continual model of flame propagation in a gas suspension of metal particles. I. One-dimensional approximation

Experimental data on combustion of magnesium particles in oxygen-containing gas mixtures are analyzed and generalized, which allowed us to develop a semi-empirical mathematical model that takes into account the integral effect of the initial particle size, pressure, and velocity of the oxidizing flow on combustion. Flame propagation in an air suspension of fine magnesium particles is considered in a one-dimensional approximation. For this purpose, a discrete-continual model of flame propagation in a gas suspension of metal particles is developed. The flammability limits in a vessel, caused by heat losses into the ambient medium and by spatial nonuniformity of the distribution of disperse-phase particles, are numerically determined, and the influence of nonuniformity and bidispersion of a one-dimensional ensemble of particles on flame characteristics is studied.__________Translated from Fizika Goreniya i Vzryva, Vol. 41, No. 2, pp. 81–93, March–April, 2005.     

氟树脂性能与加工应用(续10)

介绍了聚四氟乙烯悬浮树脂成型加工有关的物理性能,树脂的成型加工及选用方法.分别叙述了模压成型、自动模压成型和液压成型的原理、过程及设备.