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1.
根据溶胶的相互聚沉作用原理,对笔者研究成功的ABS塑料化学镀铜用的胶体铜催化活化液的溶胶性质和工艺特性作了试验。结果表明胶体铜活化液的胶粒带负电荷。新配制的活化液60℃,活化5min的情况下,其活化容量可达67.5dm^2/l,放置10h,活性会有明显下降,2天后又能恢复并稳定在一定的水平上,配制成工作液后应立即使用,4h后活性会明显下降,用离心分离的方法可望减少排放量提高利用率。  相似文献   

2.
浅谈化学镀前活化工艺的发展   总被引:12,自引:0,他引:12  
龚凡  王滨生 《应用科技》2002,29(3):59-60,63
论述了近年来国内化学镀前活化工艺的发展状况,介绍了胶体钯活化工艺的改进过程,例举了用非贵金属配制活化液的基本物质。  相似文献   

3.
脱硝催化剂活化液配制及其性能   总被引:1,自引:0,他引:1  
针对东方凯特瑞生产的蜂窝式催化剂主要活性成分,配制了7种活化液.在试验台上模拟实际工况,对失活催化剂进行活化试验,比较新鲜催化剂及活化后催化剂的脱硝效率及活化系数,并通过SEM,EDS表征研究了活化性能最好的2种活化液对失活催化剂结构和性能的影响.研究结果表明,经4#活化液活化后的催化剂,其活性达到新鲜催化剂的82%,脱硝效率达到72.2%,具有实际应用前景.  相似文献   

4.
火电厂SCR脱硝催化剂在线活化试验装置   总被引:1,自引:0,他引:1  
提出了一种SCR催化剂在线活化试验装置及其工艺流程,并对该装置的设计方法、活性测试方法及其操作步骤进行了详细说明.该装置同时具有催化剂活性测试和失活催化剂活化功能,是其他现有催化剂检测装置和活化装置功能的组合,其目的在于提供一种新的烟气脱硝催化剂活化工艺,同时也为实际工程催化剂的活性检测、活化液的配制提供一种方法.  相似文献   

5.
紫外光(UV)诱导纳米颗粒胶体射流加工可实现硬脆晶体材料亚纳米级超光滑表面的加工,根据其材料去除原理可知,伴随抛光过程的进行,胶体中TiO2纳米颗粒表面会吸附一层工件表面的被去除原子,从而影响TiO2纳米颗粒胶体的活性和光催化性.为了实现TiO2纳米颗粒胶体的循环使用,基于O3/UV高级氧化法对使用后的TiO2纳米颗粒胶体再活化机理进行了研究,同时结合紫外光诱导纳米颗粒胶体射流加工系统设计了TiO2纳米颗粒胶体活化系统,对系统内的再活化反应室结构进行了流体动力学仿真,仿真结果表明其结构设计满足TiO2纳米颗粒胶体的活化要求.  相似文献   

6.
采用溶胶-凝胶法制备了N/TiO2粉体光催化剂,用TG-DTA、IR、SEM等对其进行表征.用甲醇的光催化消除反应作为模拟反应,评价了掺氪改性TiO2的光催化活性.考察了不同活化时间、活化温度、催化剂用量以及不同气体流速对N/TiO2光催化消除甲醇的影响.实验结果表明,适量的氮掺杂可以提高TiO2的光催化活性.活化焙烧温度400 ℃、时间3 h的条件下得到的催化剂光催化活性最高.在体系流速为15 ml·min-1时,可将初始浓度为4.48g·m-3的甲醇100%消除;当初始浓度小于6.6 g·m-3时,消除率为86.7%,达到排放标准.  相似文献   

7.
以无机钛盐为原料,采用凝胶-溶胶法,制备二氧化钛纳米溶胶和掺入不同质量分数铜的Cu2+/TiO2纳米溶胶,对其进行表征。通过对甲基蓝光催化降解,对Cu2+/TiO2纳米溶胶和TiO2纳米溶胶的光催化活性进行比较,考察了聚合反应时间、表面活性剂、光照时间和强度、薄膜厚度、掺入铜离子浓度等因素对TiO2溶胶光催化活性的影响。结果表明,掺铜TiO2纳米溶胶的光催化活性较高,光催化性能优良,铜掺杂量为0.5%时效果较好。  相似文献   

8.
采用聚乙烯醇(PVA)与四乙氧基硅烷(TEOS)通过原位溶胶-凝胶法制备了PVA/SiO2有机/无机杂化溶胶,并将显色剂和植物酯酶分散于溶胶中,干燥成膜,得到一类透明度高、亲水-亲丙酮性可调、贮存性好的传感膜.该传感膜在乙酸-α-萘酯溶液中,会于可见光520 nm处出现一个新的吸收峰.传感膜在制备后的12天内活性明显下降,之后基本保持稳定,并且冷藏活性下降率要比室温保存的小很多.但不论是冷藏还是在室温下保存,被固定在杂化膜中的酶活稳定性都比在溶液状态下的明显提高.  相似文献   

9.
水性双组分聚氨酯涂料的活化期研究   总被引:1,自引:0,他引:1  
分别采用水性羟基聚丙烯酸酯分散体(PAD)和羟基聚丙烯酸酯乳液(PAE)与亲水改性多异氰酸酯固化剂配制水性双组分聚氨酯涂料(2K-WPU),通过黏度、硬度、光泽度和耐化学介质性能等测试,研究了2K-WPU在不同放置时间内的物理化学行为.结果发现:随放置时间的增加,PAD型2K-WPU的黏度降低,涂膜的起泡程度逐渐增加,涂膜硬度先降低后增加,3h后耐化学介质性能下降;PAE型2K-WPU的黏度变化无规律,涂膜硬度逐渐降低,4h后耐化学介质性能下降,气泡相对较少;PAD型和PAE型2K-WPU的粒径和光泽均无明显变化;PAE型2K-WPU的活化期一般在4h以内,而PAD型的更短,但涂膜的综合性能更优.因此施工前不能根据2K-WPU的黏度变化来判断其活化期,而须根据涂膜耐化学介质性能和外观变化来判断.  相似文献   

10.
考察了氧气气氛下 ,活化前后分别用H2 处理 0 5h对Mo/HZSM 5催化剂反应活性的影响 .结果表明 :活化后用H2 处理后催化活性显著降低 .甲烷添加O2 ,CO2 后 ,于 70 0℃时进行氧化反应 ,无苯生成 ;75 0℃时甲烷与O2 反应在进行氧化反应的同时 ,有偶联反应发生 .反应温度的提高使甲烷转化率与苯的选择性均有提高 ,但催化剂稳定性下降 ,可能归结为积炭增加和钼组分的挥发流失 .  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

13.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

14.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

15.
正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-  相似文献   

16.
We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-  相似文献   

17.
正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that  相似文献   

18.
For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the  相似文献   

19.
<正>"The Journal of Shanghai Normal University:Mathematics"is published by Shanghai Normal University as regular issues of The Journal of Shanghai Normal University each year from 2014 in English.The editors-in-chief of the issues are professors Yuhao Cong and Maoan Han.The Journal of Shanghai Normal University was started in 1958 with  相似文献   

20.
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