ROSEMOUNT GCX在线色谱变送器的改造

叙述ROSEMOUNT新一代在线色谱变送器GCX在乙烯装置中的应用所存在的问题，分析了柱系统中的样品流量的大小对分析结果的影响，提出了色谱变送器柱分析中的样品流路的具体改造方法。     

气相色谱仪分析准确度的探讨

气相色谱法具有高效、快速、灵敏和应用范围广等特点。在气相色谱分析中,要取得快速准确的结果必须考虑各种影响准确度的因素。通过实际工作中载气系统、进样系统、色谱柱分离系统等操作条件的选择来探讨如何提高气相色谱的检测准确度。     

GC-8在线色谱仪柱系统的改造及应用

阐述了丁烯－1装置用日本横河GC－8在线色谱仪改造到新装置MTBE中，对其色谱系统进行的改造及反应，经过大量实验及现场调试，已满足分析要求。     

在线色谱分析仪柱箱温度控制系统的改造

色谱柱柱箱是在线色谱分析仪的关键部件,柱箱温度的变化直接影响在线色谱分析仪分析数据的准确性,因此,对色谱柱柱箱温度控制系统进行改造,以提高在线色谱分析仪的整体性能。     

在线色谱模拟蒸馏分析仪中管式色谱柱室的开发

设计开发一种用于在线色谱模拟蒸馏的管式色谱柱室,经过线性的程序升温控制评价,温度控制精度在±0.1℃。正构烷烃校正样的重复性以及航煤样本重复性、准确性的测试表明,基于管式色谱柱室设计的在线色谱模拟蒸馏分析能够达到ASTM D2887及SH/T 0558标准的规定。管式色谱柱室的设计具有体积小、耗电少等优点,使得在线色谱仪表的整体结构简单,可靠性大大提高。     

离子交换色谱的放大─—相似模化在色谱中应用

首先从离子交换色谱本质出发，叙述色谱的历史发展以及放大进展，找出其基本的要素，根据相似模化理论探讨色谱过程的放大依据，利用相似准则进行离子交换色谱的模拟放大。     

化学工业出版社重点书推荐

现代涂料仪器分析，杂环化学——结构、反应、合成与应用（国外优秀化学著作译丛），色谱技术丛书——毛细管电泳技术及应用，色谱技术丛书——色谱在药物分析中的应用，色谱技术丛书——色谱柱技术，质谱技术丛书——同位素质谱技术与应用，质谱技术丛书——色谱质谱联用技术，药物制剂生产设备及车间工艺设计，农药环境化学。[编者按]     

离心分配色谱技术及其在天然产物分离中的应用

作为现代逆流色谱的一种，离心分配色谱(CPC)是一种新型的制备色谱技术。简单介绍了离心分配色谱的设备原理和操作方法，综述了离心分配色谱的研究现状和其应用于天然产物分离方面的相关报道，特别对离心分配色谱反应器和离子交换置换离心分配色谱等一些CPC研究领域出现的新技术进行了介绍；对离心分配色谱的研究前景进行了展望。     

有机硅色谱固定液的合成研究

有机硅色谱固定液的合成研究张增佑（南开大学元素有机化学研究所，天津，３０００７１）１前言色谱固定液是用于气相色谱分析必不可少的化学品。随着气相色谱技术的发展，色谱固定液的品种也在不断发展，牌号繁多，估计目前至少有近千种。对色谱固定液进行“优选”，早在...     

离了交换色谱的放大——相似模化在色谱中应用

道德从离子交换色谱本质出发，叙述色谱的历史发展以及放大进展，找了其基本的要素，根据相似模化理论探讨色谱过程的放大依据，利用相似准则进行离子交换色谱的模拟放大。     

废钢在底吹反应器中运动熔化及混匀的水模型实验

通过水模型实验,使用饱和氯化钾溶液制作的冰样模拟重型废钢,研究其在底吹气体搅拌反应器中的运动、融化及溶质的混匀规律。探究了单孔吹气模式下的液面高度、双孔吹气方式下的气体流量等因素对其的影响。结果表明,单孔吹气时,液面高度较低时(液面高度与直径比为0.42),气柱发展不充分,容器内环流较弱,盐球在气柱上下往复运动,融化较为缓慢。随着液面高度增加(液面高度与直径比为1.04),盐球随着环流运动,融化过程加快,按照98%标准得到的KCl的混匀时间甚至低于融化时间。双孔吹气时,A孔气体流量0.8 m3/h不变,B孔气体流量为0.5和1.0 m3/h时,盐球从吹气孔A上方加入后,在容器底部停留一段时间,在60~70 s之后才运动到顶部,沿着环流运动;B孔流量增加至1.5 m3/h时,盐球不会在底部停留,随气柱运动到吹气流量大的一侧的羽流区,其融化过程较快。在双孔吹气方案中,也发现了KCl的混匀时间低于融化时间的规律,这和融化末期盐球质量较小,释放的盐分较少有关。在本研究中,双孔吹气对盐球融化的促进作用不如单孔吹气且流量较大的方案。     

Mechanical properties of adhesive bonds reinforced with biological fabric

The paper deals with the utilization of a biological reinforcement in an area of an adhesive layer. An advantage of the biological reinforcement application is a simplification of following recyclation of adhesive bonds comparing to those with carbon and glass fibre based reinforcements. Biocomposites combining the biological reinforcement with an inorganic adhesive can be used in the area of connecting materials by means of the adhesive bonding technology. This study was focused on the analysis of an adhesive bond strength when the bonds were reinforced with biological fabric such as jute, flax and cotton. It evaluates the quality of the adhesive layer by means of SEM. The aim of this experiment was to describe an influence of the biological reinforcement in the form of fabric on the adhesive bond strength loaded with various loading speeds from 0.5 to 300 mm/min. The experimental part is devoted to the research on the influence of added fabrics of the natural origin on the shear strength of the adhesive bond which is prepared with the polymer adhesive. The experiment results proved a benefit of the reinforcing biological fabric in the layer of the adhesive. The reinforcement of the adhesive bond with the layer of the flax and the cotton showed in the positive way with the increase of the adhesive bond strength up of ca. 50%. The biological reinforcement was not fully wetted with the resin which did not considerably influence the adhesive bond strength.     

Pd-Pb/SiO2催化高浓度乙烯基乙炔加氢合成丁二烯

研究了硅胶负载钯铅双金属催化剂催化高浓度乙烯基乙炔加氢合成丁二烯过程。结果表明,加入适量的铅可起到分隔钯纳米粒子,阻碍钯纳米粒子团聚的作用,从而提高催化剂的催化活性,最佳Pb/Pd摩尔比为0.2。继续提高Pb/Pd摩尔比时,会生成铅钯合金相,造成催化剂活性降低。X射线光电子能谱结果表明,催化剂的催化活性与Pd 3d的电子结合能呈正相关关系。制备催化剂过程中,还原温度对催化剂的结构和催化性能影响显著。在350℃下还原得到的催化剂中金属氧化物还原不彻底,催化剂活性较低;还原温度为450℃时,则会引起钯纳米粒子烧结,造成催化剂的催化活性和对丁二烯的选择性同时降低;催化剂的最佳还原温度为400℃。在40℃催化乙烯基乙炔反应40 h后,积炭造成催化剂的孔道堵塞,催化剂失活。因此,需要进一步开展改善催化剂的抗积炭能力和使用寿命方面的研究。     

Combined electrochemical and surface analysis investigation of degradation processes in polymer electrolyte membrane fuel cells

Fuel cells allow an environmentally friendly and highly efficiently conversion of chemical energy to electricity and heat. Therefore, they have a high potential to become important components of an energy-efficient and sustainable economy. The main challenges in the development of fuel cells are cost reduction and long-term durability. Whereas the cost can be significantly reduced by innovative mass production, the knowledge to enhance the lifetime sufficiently is not available.Surface science analysis methods used for the characterization of the new and used electrodes can be use to determine the alterations in the fuel cell components and in this way to identify the degradation processes, but they do not allow to quantify the influence of the alterations in the electrodes on the electrochemical performance. For this purpose electrochemical methods are necessary; especially the electrochemical impedance spectroscopy (EIS) allows to separate the performance losses individually and to assign them to different components and processes of the cell via a model, whereas the choice of the right model can be problematic.Two important and distinct structural degradation processes were identified by surface analysis of the electrodes before and after fuel cell operation: first, the decomposition of poly tetra-fluoro-ethylene (PTFE) which is used as an organic binder and as a hydrophobic agent in the electrodes and second, a change of the structure of the catalysts. The observed decomposition of the PTFE is associated with a decrease of the hydrophobicity of the electrode. A loss of hydrophobicity influences drastically the required operation conditions and leads to a more critical water management of the fuel cell. In contrast, the alteration of the catalysts structure in the electrodes causes an irreversible decrease of the electrochemical performance. In polymer electrolyte fuel cells (PEFCs) a particle agglomeration of the platinum catalysts at the cathodes is detected.With EIS the effect of two different degradation processes in the membrane-electrode-assembly was quantified. During continuous operation the degradation of the PTFE induces an approximately two times higher performance loss compared with the performance loss related to the agglomeration of the platinum catalyst.     

ChMI/ MMA/AN悬浮共聚物与PVC共混的研究

通过悬浮共聚得到了N－环己基马来酰亚胺（ChMI）、甲基丙烯酸甲酯（MMA）、丙烯腈（AN）三元共聚物（PCMA），用作耐热改性剂与PVC共混。考察了共聚物用量对共混物热性能、力学性能、流变性能的影响，用扫描电镜（SEM）观察其断面。结果表明：随共聚物用量的增加，共混物的玻璃化温度和维卡软化点明显提高；PVC第一阶段降解速率减小，降解守毕后平台区残留量逐渐上升；拉伸强度明显提高，冲击强度在一定比例范围内几乎不变；熔体表观粘度增加，呈假塑性流体。     

扩压式自泵送流体动静压型机械密封性能分析

密封端面开启力是保证非接触式机械密封非接触运行的重要指标。为克服普通自泵送流体动静压型机械密封端面开启力随转速增大而减小这一不足，基于离心式泵或压缩机的扩压器工作原理提出了一种扩压式自泵送流体动静压型机械密封。数值模拟比较了普通自泵送和扩压式自泵送流体动静压型机械密封的密封性能，探讨了密封面结构参数和工况参数对扩压式自泵送流体动静压型机械密封性能的影响规律。结果表明：扩压式自泵送流体动静压型机械密封相比同等螺旋槽参数的普通自泵送流体动静压型机械密封的密封界面开启力提升了50%以上，并随转速增大而增大；随着扩压环槽增宽，开启力和泄漏率都显著增大；减小扩压环槽深度，能有效提高开启力；扩压环槽结构尺寸的变化基本不影响槽扩宽比、槽数和螺旋角对密封性能的影响规律。在一定的工况参数下，通过结构参数匹配，扩压式自泵送流体动静压型机械密封可以获得较优的密封性能。     

Écoulement de Taylor‐Couette en géométrie finie et à surface libre

The reactors of Taylor‐Couette type are relatively recent application in the engineering processes field. The stability and the flow structure in this device are examined under the effect combined of the free surface and the fluid's height in annular space. The exploitation of the flow regimes is carried out according to the number of Taylor for various values of aspect ration Γ. By means of ultrasonic velocimetry (UPV) we determine axial average velocity profile and the axial wavelength. We also carry out the spectral analysis by Fourier's fast transform of the fluctuations associated with the average velocity values in order to analyze the flow structure. We particularly aim for checking the presence or the absence of the azimuth wave according to the filling height and the rotational velocity imposed. We highlight the effects of free surface and aspect ratio on the conditions of appearance of the second instability ( wavy mode). The analysis of the fluctuation shows that the appearance of the azimuth wave regime (Wavy mode) is delayed when the aspect ration decreases. Below a critical value noted Γc = 10, the azimuth wave regime is not observed any more.     

台阶式并行微通道内液液两相流流型及其转变机理

利用高速摄像仪研究了台阶式并行微通道内液液两相流流型及其转变机理。以甘油水为分散相、含3% Span 85的环己烷为连续相,观测到了滴状-滴状流、过渡-滴状流、喷射-过渡流和喷射-喷射流4种流型;以两相流量为坐标轴绘制了流型图,并获得了流型转变线;分析了流型的转变机理。考察了分散相黏度对流型及其转变的影响机制。随着分散相黏度的增大,流型转变线整体向下移动,滴状-滴状流区域变小,喷射-喷射流区域变大。最后,运用介尺度概念分析了并行微通道内液液两相流非均匀结构的动态效应。     

Confocal microscope—A valuable tool for examining wood-coating interface

The suitability of confocal laser scanning microscopy (CLSM) in examining a wood-coating interface was evaluated using a clear coating system. A comparison of the images of the wood-clear coating interface obtained using CLSM and light microscopy (LM) showed a marked superiority of CLSM in revealing the details of the physical nature of the interaction between the clear coating and the wood cell walls in the surface layer. The most distinct advantage of CLSM was in its ability to clearly resolve penetration of the coating into very fine cracks in cell walls, details not obtainable with LM. The information presented here demonstrates that CLSM has the potential to greatly enhance our understanding of the physical aspects of an interaction between the wood and coating at the interface.     

Influence of organic pigment particles on millbase flow of nitro-cellulose/alcohol-rich liquid inks

Millbase flow of nitro-cellulose/alcohol-based inks deteriorates above a critical pigment weight fraction in the ink which differs from pigment to pigment. Below this critical concentration the inks are flocculation-resistant by virtue of a stabilizing adsorbed layer of NC resin on the pigment particle surfaces. The pigment particles are large aggregates of crystals, from which additives such as abietyl resin have been shown to dissolve off into the ink medium. The aggregates are associated with liquid medium immobilized within the shear boundary near the pigment/medium interface (includes adsorbed layers and liquid within pores). This results in the effective pigment volume fraction in the ink being higher than that calculated from the weight fraction. When considered in terms of the effective volume fraction, most of the pigments have the same critical concentration of about 0.2–0.25. This indicates that deterioration in flow at higher concentrations is due in the first instance to crowding of particles, rather than to the failure of the mechanism of flocculation resistance per se. The robustness of the flocculation resistance is indicated by a low rate of increase of the strength of the structure with an increase in the effective volume fraction above the critical concentration. Robustness is important in maintaining manageable flow at high concentrations. Increasing the proportion of ethyl acetate in the solvent blend can adversely affect the millbase rheology of dispersions of some pigments in NC ink media due to induced flocculation and structure formation. The improved solvency of the blend for NC resin has been shown to reduce the amount of NC resin adsorbed on the particles of an ester-sensitive pigment. Other pigments give inks with rheology insensitive to ester content. This is attributed to more specific interaction of the NC resin with the pigment particle surfaces. The effect of temperature on flocculation resistance is consistent with these views.