A hexane solution deposition of SnS2 films from tetrabutyltin via a solvothermal route at moderate temperature

SnS₂ films have been deposited on glass and alumina plate substrates by the reactions between an organotin precursor [tetrabuyltin, (CH₂CH₂CH₂CH₃)₄Sn] and carbon disulfide in n-hexane at the temperature range 180-200 °C for 10-40 h. The reaction system was oxygen free and applied at a moderate temperature. The films so prepared were characterized by techniques of X-ray diffraction, Scanning electron microscopy, Raman and Mössbauer spectroscopies. The films deposited on glass as well as on alumina plate have an average thickness of 30 μm, but have different rose-like morphologies, which are influenced by both the anisotropic growths of crystals and the different substrate structures. Photoluminescence measurements show that the films have an emission peak at approximately 590 nm.     

Cr12MoV钢冷挤压成形模强化工艺的研究

针对Crl2MoV钢冷挤压成形模热处理存在的质量问题，对加热温度和方式进行了大量的试验研究，在此基础上，提出了改进的快速加热工艺。结果表明，经该工艺处理后，模具使用寿命得到显提高。     

横波速度各向异性初步探讨：—多波勘探资料的应用

在纵波、SH 型横波资料处理和解释过程中,我们发现四川 HBC 地区地下介质普遍存在方向各向异性。当横波通过方向各向异性介质时,分裂成两个波:一个波的偏振方向与裂缝平行,叫快横波;另一个波的偏振方向与裂缝走向垂直,叫慢横波。采用相应的观测和处理方法,便可获得快横波和慢横波剖面。根据同一界面的快、慢横波的旅行时可以求得各向异性系数。同样,还可以利用 SH 波与转换波的速度比求取各向异性系数。各向异性系数的大小,反映了裂缝的发育程度。如果野外作了 X、Y 分量观测,室内又作了坐标旋转处理,那么,就可以进一步确定裂缝带的方向。如果未作上述工作,也可以根据构造线走向,大致确定裂缝带的发育方向。     

Thermal decomposition and micropore formation in PEK,PEEK and PES

At strain rates greater than about 10 the deformation of polymers is an adiabatic process which can lead to the generation of very high localized temperatures. These may be well in excess of the temperatures required for thermal decomposition of the polymer to occur. It is speculated that gaseous products arising from such decomposition may act as the source of microcavities and craze initiators. Experiments are described in which the thermal decomposition reaction parameters of polyetherketone, polyetheretherketone, and polysulphone are measured using differential scanning calorimetry and thermogravimetric analysis, and the decomposition products analysed by mass spectrometry. The results indicate that the proposed mechanism could act as a source of micropores with total pore volumes amounting to several per cent of the material volume.     

Co-evolution as a computational and cognitive model of design

Co-evolutionary design has been developed as a computational model that assumes two parallel search spaces: the problem space and the solution space. The design process iteratively searches each space using the other space as the basis for a fitness function when evaluating the alternatives. Co-evolutionary design can also be developed as a cognitive model of design by characterizing the way in which designers iteratively search for a design solution, making revisions to the problem specification. This paper presents the computational model of co-evolutionary design and then describes a protocol study of human designers looking for evidence of co-evolution of problem specifications and design solutions. The study shows that co-evolutionary design is a good cognitive model of design and highlights the similarities and differences between the computational model and the cognitive model. The results show that the two kinds of co-evolutionary design complement each other, having strengths in different aspects of the design process. Electronic Publication     

A Shortcut Method for Estimating the HETP of Structured Packed Distillation Columns at Elevated Pressure

A shortcut model is developed for predicting the HETP of a structured packed distillation column operating at elevated pressure. The proposed model incorporates the geometrical parameters of the packing, physical properties of the vapor and liquid phases, and the hydrodynamics of the two‐phase flow. The proposed model is tested and validated by comparing the predicted results with the present experimental data and some published HETP data. The results show that the proposed model can predict the experimental data with a deviation smaller than 20 %.     

一种新型背面接触式H~+-ISFET

简要地介绍了氢离子敏场效应晶体管(H~+-ISFET)的基本结构和工作原理,提出了一种新型背面接触式H~+-ISFET。对该结构在版图、工艺设计中的有关问题,进行了探讨。最后指出:它在pH值的测量中有较好的实用价值。     

雨洪资源利用的必要性及其措施探讨

遵循水的规律,坚持防汛抗旱并举,实现防汛工作由单纯的洪水控制向洪水资源化转变和单一农业性抗旱向以保证包括城市供水为重点的全面抗旱转变是新时期治水新思路的重要观点之一.文章在回顾雨洪资源利用发展简史的基础上,就其必要性、可行性和利用方式进行了初步探讨.     

对我厂防治加热管内碳酸钙垢的思索

分析了我厂两碱法原卤净化后,加热管内壁结碳酸钙垢的原因,探讨了我厂采取加盐酸、加阻垢剂、用超声波阻垢器的方法,以及对加热管内碳酸钙垢防治的情况和存在的问题.