聚氨酯分散剂在液体靛蓝制备中的应用

采用异佛尔酮二异氰酸酯(IPDI)、聚乙二醇200、400、600、800(PEG200、PEG400、PEG600、PEG800)、2,2-二羟甲基丙酸(DMPA)、1-苯基-1,2-乙二醇、中和剂三乙胺(TEA)、甲乙酮肟等为原料,制备了一种阴离子聚氨酯分散剂.通过FTIR、GPC、TG表征了分散剂的结构与性能.利用自制的分散剂采用研磨法制备了液体靛蓝分散液,以液体靛蓝分散液粒径、离心稳定性、储存稳定性为指标,探讨了分散剂链长、用量对分散液性能的影响.结果表明,研磨1 h后,以PEG400为软段合成的聚氨酯分散剂用量为染料质量的60％时制备的液体靛蓝粒径为277.1 nm,1000 r/min离心稳定性达到93.98％,3000 r/min离心稳定性为51.13％,常温放置7 d后粒径变化在20 nm以内,染色后织物的颜色深度(K/S)为10左右,约是粉状靛蓝染色K/S的2倍,染色织物的颜色性能并未改变,SEM显示分散体颗粒大小分布均匀,与分散剂甲基萘磺酸钠的甲醛缩合物(MF)和木质素85A相比,其分散体系稳定性差别不大.     

热管传热性能对小型热管换热器散热效能影响

在零重力辅助下,小热管热阻是小型热管换热器散热效能的重要影响因素之一。基于集总参数法对于换热器系统数值计算的高效性思想,建立了热管、热管换热器的集总参数模型。对同一热管换热器选用不同传热性能的热管,在不同传热温差和流体质量流速下,就其散热效能进行了数值计算。计算结果表明,在零重力辅助下,热管换热器管内热阻存在一临界值Rcri。当热阻RHP≤Rcri时,管外热阻起主导作用,热管换热器的散热效能εh几乎不随热管管内热阻的值而变化。     

超微粒乳剂的制备及量子尺寸效应的研究

本文制备了四种不同粒度的超微粒AgBr照相乳剂,用X射线衍射技术对其粒子的大小进行了测定;观察到乳剂的紫外吸收峰随晶体颗粒的减小表现出逐渐蓝移;本文提出晶体表面的悬键的存在使得纳米晶体的平均键能升高,并对纳米AgBr乳剂的量子尺寸效应进行了解释。     

Transport properties of helium near the liquid-vapor critical point. IV. The shear viscosity of3He and4He

Shear viscosity measurements with a precision of 0.05% are reported for³He and⁴He along near-critical isochores 0.85 c <1.12, where _c is the critical density. The temperature range was –10^–4<<1, where =(T – T _c)/T _c is the reduced temperature. The experiments were carried out with a torsional oscillator operating at 158 Hz, driven at resonance in a phase-locked loop. The absolute value of the viscosity was obtained by calibration at the superfluid transition of⁴He, based on published values and from direct calculations using the free decay time constant of the oscillations. The data are analyzed in terms of a model using the recent mode-coupling (MC) expressions by Olchowy and Sengers, and where account is taken of the earth's gravity effects. The theory could be fitted very well to the experiment with a single free parameter, the cutoff wave numberq _D, which was found to be 3.0×10⁶ and 7.0×10⁶ cm^–1 for³He and⁴He, respectively. We have used for the critical exponent the MC predicted value of z=0.054, which permits a fit superior to that using z=0.064 predicted by dynamic renormalization group (DRG) theories. Detailed comparisons are made between the model calculations and data for various isochores and isotherms and good agreement is obtained. The effects of gravity are described in some detail. The predicted frequency effect in viscosity measurements is calculated for³He and is shown to be obscured by gravity effects. Using the Olchowy-Sengers formulas, we have also fitted the MC theory to the critical thermal conductivity data of³He, again withq _D as the only free parameter. This fit gaveq _D=6 × 10⁷ cm^–1, which in the ideal situation should have been the same asq _D from viscosity. We also discuss a representation of the³He viscosity data along the critical isochore by a power law and first correction-to-scaling erm. Using the viscosity and the critical conductivity data for³He, we have calculated the dynamic amplitude ratio and obtained =1.05±0.10, in agreement with predictions from MC and DRG theories. Also, agrees with data of classical fluids. Finally, a comparison is made of recent shear viscosity data for CO₂ by Bruschi and Torzo with those on He. The CO₂ data are also analyzed in terms of the MC theory, and the discrepancies are discussed. In the Appendices, we present the results of new compressibility measurements on³He along the critical isochore, as used in the MC analysis. We also present a brief analysis of the fluid hydrodynamics in the torsional oscillator leading to relations for the viscosity as a function of the measured quantities. Finally, we give a short outline of the vertical density profile calculations from the earth's gravity field for the calculations of the viscosity nearT _c.     

Mn2+在Zn2SiO4中的发光

利用Sol-gel法制备掺Mn^2 的Zn2SiO4的前驱体，并将前躯体在弱氧化气氛下在1000℃煅烧2h，得到掺Mn^2 的Zn2SiO4试样。X射线衍射分析确定试样为α-Zn2SiO4晶相。荧光分析测定试样的激发光谱和发射光谱。结果显示Mn^2 掺杂的α-Zn2SiO4可发蓝色和绿色荧光，这一结果显然不同于以前的文献报道。同时，我们讨论了Mn^2 在Zn2SiO4中产生这一新型发光性质的机理。     

基于RFID和GPRS的远程监控系统设计与实现

针对目前监控系统监测点分散、数量大、信息统计难的问题,提出了一种基于射频识别(RFID)技术和GPRS技术的远程监控系统,进行了系统的总体设计,给出了详细的手持读写器硬件和软件设计,主要包括射频读写模块、GPRS模块、主控制器模块等。射频读写模块采集数据后,通过GPRS模块将数据上传至上位机进行分类管理,实现了监控系统自动化,提高了管理效率。整个系统采用锂电池供电,成本低,使用方便,安全可靠。     

《建筑结构学报》引文统计与分析

以《建筑结构学报》为调查对象，对１９９１年～１９９６年所刊载的论文，运用引文分析法，对其引文的数量、文献类型、语种及年代分布进行了统计分析，并做出相应的评价．     

羟基磷酸铁铵的制备与表征

采用硫酸亚铁和磷酸为原料,在尿素存在的条件下,水热合成得到高纯度的羟基磷酸铁铵。研究发现,反应温度不同得到的羟基磷酸铁铵的结晶度会有所不同,形貌差异较大。利用XRD、SEM、TG-DTA和红外分析等手段对制备的样品组成、结构、晶型和形貌做分析表征,分析了羟基磷酸铁铵在加热过程中的相变过程。结果表明,在静态羟基磷酸铁铵中,磷酸和铁具有固定的化学计量比,经高温煅烧后得到高纯度磷酸铁,可应用其制备锂离子电池正极材料磷酸铁锂的前驱体,且此法合成工艺简单,具有良好的工业应用潜质。     

连续纤维补强陶瓷复合材料

本文论述了连续纤维补强陶瓷复合材料的性能、结构、特点、种类及主要制备方法,提出了这类材料亟待解决的问题     

基于OrcaFlex水下采油树钢丝绳下放作业窗口研究

水下采油树的下放安装作业环境载荷非常复杂,下放作业窗口是我国南海水下采油树下放过程中亟待解决的关键问题.针对东方1-1气田73 m水下采油树钢丝缆绳下放安装方法,分析了水下采油树下放作业过程.利用OrcaFlex建立了工程船-钢丝缆绳-水下采油树系统的耦合模型,研究了不同浪高、流速、波浪方向角等关键因素对水下采油树安装...