GAS ABSORPTION IN A HOLLOW FIBER DEVICE

The absorption of S0² and NH³ from air and air/CO ² streams was studied for the first time in a certain novel hollow fiber mass transfer device, for various inlet gas compositions, liquid compositions, gas flow rates, and liquid flow rates. The gas and liquid flows were countercurrent. Analyses of the amounts of S0²and NH³ absorbed demonstrate that the hollow fiber unit has a relatively small membrane resistance and is an effective gas scrubbing device. Additionally, it offers a large interfacial area per unit volume, and avoids flooding problems entirely     

浅谈涤纶FDY生产新技术──TCS一步法的特点

ＴＣＳ系指德国巴马格公司最新推出的细旦涤纶纺丝技术，该技术突破了热辊拉伸这一传统的涤纶纺丝模式，以甬道中的热空气为传热媒体，使丝条在稳定均一的热环境中完成拉伸过程。ＴＣＳ与ＣＷ６超高速卷绕机配合使用，可在极高的纺速下一次形成比较完善的纤维结构，从而获得条干和染色性能优异的成品纤维。该文介绍了该技术的工艺流程、设备结构和产品特点等。     

接枝改性腈纶织物亲水性能的研究

采用酰胺类亲水性单体对腈纶织物接枝改性,利用正交试验法对溶胀剂、乳化剂、引发剂的种类和用量进行了选择。结果表明,选择溶胀剂NaSCN 0．8 g／L,乳化剂十二烷基苯磺酸钠0．4g／L,引发剂BPO 0．4 g／L,接枝改性效果较好。腈纶织物的吸湿率由0．2％提高至5．0％,保水率由3％提高至13％。     

PVA纤维混凝土力学参数间的相关关系

对高强高模聚乙烯醇(PVA)纤维混凝土材料进行大量标准材性试验，并在此基础上研究了PVA纤维混凝土各种常见力学参数之间的关系，为更好、更方便的应用PVA纤维混凝土打下基础；研究表明，相对于普通混凝土材料，加入PVA纤维的混凝土材料各种参数之间的关系稍微改变，随纤维含量的变化也有所变化。     

Transient Thermal Deformations of the Interphase in Polymer Composites

Heterodyne micro-interferometry was utilized to measure out-of-plane transient displacements in the interphase due to thermal cycling. In-situ measurements were made on single carbon fiber/epoxy samples with interphases of varying glass transition temperature. Interphase properties were tailored such that one set of samples had fibers which were coated with a low T_g resin, another set had a higher T_g coating, and in the third set the fibers were uncoated. The interferometric data demonstrated that interphase T_g has a significant effect on the rate and magnitude of the thermal deformations at the fiber/matrix interface. The presence of a low T_g interphase caused an increase in the magnitude of the thermal displacements due to a local softening of the matrix and increase in coefficient of thermal expansion. In addition, the rate at which the displacements increase was also higher due to the reduction in T_g. Samples with untreated fibers (no tailored interphase) behaved as if a low T_g interphase had formed. Experimental displacement profiles were also compared with finite element predictions to assess the behavior of the tailored interphases.     

Low-temperature catalytic combustion of methane over Pd/CeO2 prepared by deposition–precipitation method

Ceria supported 2 wt% Pd catalysts for low-temperature methane combustion were prepared by the impregnation (IM) and deposition–precipitation (DP) methods, which are denoted as Pd–IM and Pd–DP, respectively. DP was found to be an available method for achieving high activity and stability of the Pd/CeO₂ catalyst. The temperatures for methane ignition (T_10%) and total conversion (T_100%) over Pd–DP are 224 and 300 °C at GHSV of 50,000 h⁻¹, which are 83 and 110 °C lower than the corresponding temperatures of Pd/Al₂O₃. X-ray diffraction (XRD), Raman and X-ray photoelectron spectroscopy (XPS) analyses show that palladium species in Pd–DP is highly dispersed, positively charged and difficultly reduced. Raman spectra disclosed that the largest concentration of defects and/or oxygen vacancies was formed in Pd–DP catalyst. A kind of cationic PdO^δ+ sites with higher binding energies than PdO are in close vicinity to the oxygen vacancies in the CeO₂ support and might act as the active centers for methane oxidation. Furthermore, the deactivation and steam aging tests for Pd–DP showed that the performance of this type of palladium was very stable and could be repeatedly recovered after several long time aging tests.     

含纳米组装高分子的抗静电纤维

用化学方法制得含纳米组装高分子的抗静电剂，将其与聚酯切片共混纺丝，制得永久性抗静电聚酯纤维。用DTA，显微镜等研究了抗静电剂及抗静电纤维的结构、性能。当抗静电剂质量分数为0.6%时，纤维的抗静电性、耐洗涤性优良、稳定。初步探讨了纤维的抗静电作用机理。     

Influence of Matrix Properties on Fragmentation Test

Physical aging was used to vary the mechanical properties of model single fiber composites without changing the chemistry at the interface in order to study how property changes affect the measurement of interfacial adhesion by the fragmentation test. The properties of epoxy matrix/AS4 single fiber composites driven to full cure (T_g = 166°C) are altered by annealing below T_g. Neat resin samples with identical thermal histories are tested. All aged panels show roughly the same embrittlement with aging characterized by an average 30% decrease in tensile failure strain and 7.3% increase in compressive yield relative to quenched samples. Fragmentation results indicated no change between aged and quenched samples. Results are discussed in terms of micromechanics models for the fragmentation test. Strain at fragmentation increased with aging. This was related to the residual stress state in the model composite and the possibility of the zero stress state of the single fiber composites increasing with thermal annealing.     

Carbonaceous materials from end-capped alkynes

A series of terminally protected alkyne derivatives iPr₃Si-(CC)_n-Si iPr₃, n=2, 3, 4, 6 was prepared by the Hay oxidative coupling. The longest oligoyne chain was in 1,12-bis-(triisopropylsilyl)-1,3,5,7,9,11-dodecahexayne (V), that is a new substance exhibiting reasonable stability even in the solid state (m.p. 112.5°C). The prepared oligoynes were studied by UV-Vis, Raman, FTIR, ¹³C-NMR and mass spectroscopy. The corresponding de-protected free alkynes polymerized spontaneously in n-hexane solution at room or sub-room temperatures towards new carbonaceous materials, which were characterized analytically and spectroscopically.     

光纤光栅位移传感技术研究

介绍了一种光纤光栅传感器的在曲面空间位移测量方面的应用.随着外界应力的变化,光纤光栅的Bragg中心发射波长将发生相应的移动.利用此特性,提出并实现了一种精密的用光纤光栅作为敏感元件测量曲面空间间隙位移的方法,获得了光栅Bragg波长偏移量与曲面间隙位移量之间的曲线关系,其灵敏度可达3.5013 nm/mm,最后对实验结果进行了分析.