4m卷扬机的改造

介绍了锦屏磷矿4m卷扬机改造的内容，包括对卷筒进行修补、钢丝绳更新、轴瓦更新、箕斗及深度指示器的改造、抱闸磨擦带的更换等。     

Robocasting of alumina hollow filament lattice structures

Robotic controlled deposition (robocasting) of an aqueous colloidal α-Al₂O₃ gel for manufacturing of cellular ceramics with periodical lattice structure was investigated. The colloidal gel was loaded with 50 vol% α-Al₂O₃ and exhibits shear-thinning behavior, a shear modulus of 288 kPa and a yield-stress of ～700 Pa. Tubular filaments of circular and rectangular cross section having an outer diameter of 1.5 mm and a capillary diameter of 0.75 mm were deposited in an oil bath to fabricate lattice truss structures with free spanning filaments. After freeze drying the robocast grids were sintered in air at 1550 °C. X-ray μ-CT revealed continuity of the tubular filaments for long distances (～650 mm). Critical conditions to avoid capillary collapse were discussed by considering bulging stress and pressure distribution within the hollow filament. At short filament length oil infiltration into the capillary driven by capillary suction supports the tubular filament whereas oil flow driven by movement of the tool nozzle causes pressure difference to increase linearly with increasing filament length.     

纤维缠绕复合材料固化制度实用设计研究（Ⅱ）

本文论述热固性复合材料固化制度的设计原则和基本方法,归纳长期积集累的经验、数据及国内外研究成果,列出相关的原材料热特性参数;重点讨论了厚壁复合材料结构固化过程中的温度滞后和过热的本质、危害及预防措施;同时介绍了三种固化制度模拟验证实验方法。     

DRYING BEHAVIOR OF ACETATE FILAMENT IN DRY SPINNING

Drying behavior of acetate filament in dry spinning is investigated, including the elongational deformation of polymer solution thread in the early stage of drying. Variations of diameter, velocity, temperature, solvent concentration profile in the thread and tension distribution along the threadline in the spinning column, are calculated for spinning conditions encountered commercially by means of the equations of simultaneous momentum, heat and mass transfer between the thread and hot air flow in the spinning column. Concentration and temperature dependencies of the mutual diffusion coefficient from desorption experiment are correlated by the free volume theory. The elongational viscosity is estimated from the shear viscosity data using Krevelen theory. Residual acetone concentratio in the thread and tension at the exit of the spinning column are compared between the calculated results and the experimental data by a commercial apparatus; satisfactory agreement is found. Rapid decreases of temperature and surface concentration of the dope thread after extrusion confine the elongational deformation within several centimeters below the spinnerette. Initial elongational rate and die swell ratio are related to the winding velocity and tension at the exit of the spinning column. The tension is determined mainly by initial viscous force and air drag.     

Optimizing Factors on High Concentration of Ozone Production with Dielectric Barrier Discharge

The gap distance, electrode material, voltage and gas flow velocity were optimized with gas pressure variation of dielectric barrier discharge (DBD) for producing high concentration of ozone. There exists an optimum gas pressure at which the highest ozone concentration is produced with other parameters being fixed. This optimum gas pressure value changes accordingly as the other parameters changed. As the discharge continues at the optimum pressure, the ozone concentration could increase or decrease slowly. This aging effect has different characteristics with the metal electrode material and the impurity level of the oxygen gas used for ozone generation. The aging effect is supposed to be related with the catalytic effect of metal oxide, which is generated in the discharge zone. The change in the characteristic of optimum pressure by the other parameters, indicate that the ozone concentration is deeply related with the filament self-organization characteristics of DBD. At the final optimized condition, the ozone concentration was higher than 22.5 wt.%.     

连续玻璃纤维增强PLA复合材料3D打印技术研究

以聚乳酸(PLA)为基体,连续玻璃纤维为增强体,采用熔融浸渍工艺制备连续玻璃纤维预浸丝,将制得的预浸丝作为3D打印耗材用于熔融沉积(FDM)的3D技术来制备连续玻璃纤维增强PLA复合材料试样,并研究了打印温度、层厚和打印速度对复合材料力学性能的影响。结果表明,当打印层厚为0. 5 mm,打印温度为230℃,打印速度为2 mm/s时,连续玻璃纤维增强PLA复合材料的弯曲性能最佳,弯曲强度和弯曲模量分别为327. 84 MPa和20. 293 GPa。综合考虑复合材料的力学性能、表面质量和尺寸稳定性,连续玻璃纤维增强PLA复合材料的最佳打印层厚为0. 5 mm,适宜的打印温度范围为200~220℃,打印速度范围为2~4 mm/s。     

Reel-to-reel wet coating as an efficient up-scaling technique for the production of bulk-heterojunction polymer solar cells

In this paper we report for the first time very promising results in up-scaling coating processes for thin flexible polymer solar cell (PSC) application. Two functional layers for PSC devices, the conducting poly- (3,4-ethylene-dioxythiophene):polystyrenesulfonate and the photoactive one (poly-3-hexylthiophene/[6,6]-phenyl-C61-butyric acid methyl ester), could be successfully prepared by continuous reel-to-reel (R2R) wet coating of low-viscosity solutions and dispersions on ITO-coated PET substrates. A laboratory coating machine (LBA-200) was used for R2R slot die coating (1-4 m/min). Out of this R2R-produced bilayer-system PSCs were accomplished and tested. Light power conversion efficiencies up to 1.7% under AM 1.5 illumination (100 mW/cm²) could be obtained.     

Manufacturing and testing of a CFRC sandwich cylinder with Kagome cores

Filament winding and twice co-curing processes were proposed to make a carbon fiber reinforced composite (CFRC) sandwich cylinder with Kagome cores. Axial compression was carried out to reveal the stiffness and load capacity of the fabricated sandwich cylinder. Compared with the stiffened cylinder with similar dimensions and mass, the sandwich cylinder is shown to be stiffer and stronger by several times. Restrained by the double skins, the buckling of lattice ribs is effectively suppressed, leading to the elimination of the dominant failure mode. Skin crippling and strength failure were observed in the testing to be the competing failure mechanisms of the lattice sandwich cylinder. The prediction based on the weakest link of these mechanisms only overestimates the testing load capacity by 30%. The novel sandwich structure shows the promise of lattice composites in upgrading the mechanical properties.     

基于OpenGL的筒形压力容器缠绕仿真

纤维缠绕是制造高强度复合材料制品的一种重要工艺方法,被广泛应用于航空、航天、建材、化工等领域.在Visual C 环境下,结合OpenGL实现了筒形压力容器的缠绕仿真.利用OpenGL的相关命令和函数对筒形压力容器进行三维建模,仿真程序根据输入的基本参数进行纤维缠绕的仿真.     

嵌入式夏季牛仔布用纱的开发

探讨应用嵌入式纺纱技术开发夏季轻薄牛仔布用纱的方法和效果.提出了嵌入式夏季牛仔布用纱的开发思路,通过选配原料、进行长丝卷装准备和细纱机相关设备改造、合理配置前纺和细纱工艺参数及采取必要的操作和质量控制措施,成功纺制出两种嵌入式复合纱.认为,应用嵌入式复合纺纱技术可开发出号数较细、强力较高、条干较好、耐磨性较强的嵌入式复合纱,较好地满足夏季牛仔布用纱的质量要求.