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1.
聚乙烯醇胺肟螯合纤维的合成及对钯的吸附   总被引:4,自引:0,他引:4  
利用^60Co-γ射线预辐照接枝和胺肟化反应合成了聚乙烯醇胺肟螯合纤维。预辐照剂量支液的组成对接枝率,胺肟基因含量和吸附容量有影响。研究了PVAAO螯合纤维对钯的吸附性能。  相似文献   

2.
聚丙烯胺肟螯合纤维的合成及性能   总被引:5,自引:0,他引:5  
采用^60Co-γ射线预辐照方法合成了聚丙烯胺肟(PPAO)螯合纤维。研究了影响接枝率和胺肟基团含量的因素。结果表明,接枝率随预辐照剂量、单体浓度、反应时间和反应温度的增加而增加。羟胺溶液的pH=7时,胺肟基团含量最高。胺肟化反应时间大于1.5h,胺肟基团含量不再增加。该纤维对金的吸附容量为99.1mg/g干纤维,对钯和铜也有较好的吸附性能。  相似文献   

3.
活性炭纤维吸附钯的基本特征   总被引:7,自引:1,他引:6  
用原子吸收分光光度计、X射线衍等手段,研究了粘胶基活性炭纤维对Pd^2+的吸附。结果表明:活性炭纤维不但能吸附较多的Pd^2+,而且能与Pd^2+发生氧化还原发反应,吸附了Pd^2+的活性炭纤维上出现金属钯颗粒,且粒度较小。  相似文献   

4.
姚占海  徐俊 《高分子材料》1997,4(4):9-12,19
利用一次辐照接枝和胺肟化反应合成了含羧基的聚丙烯胺肟(PPAO-AA)螯合纤维。研究了影响接枝率,胺肟基团含量和吸附容量的因素,结果表明,接枝率随预辐照剂量的增加而增加,单体摩尔比为1时,接枝率最高,在pH=5时,对Cu(II)离子的吸附容量达0.84mmol/g干纤维。  相似文献   

5.
探讨了在较高氨分压下,活性炭纤维(ACF)对于极性吸附质氨的吸附过程,证明在此过程中,ACF孔径结构的重要性。初步讨论了不同的孔径结构下的不同的吸附行为。  相似文献   

6.
制备了载锰剑麻基活性炭纤维(SACF-Mn),并研究了制备条件对SACF-Mn的结构及表面形态的影响。研究表明:增大锰溶液的浓度,提高pH值,高价态的锰离子都有利于SACF对锰的吸附;锰化合物的阴离子类型,不仅影响SACF对锰的吸附,而且对载锰后SACF的表面形态的影响更显著  相似文献   

7.
制备了载锰剑麻基活性炭纤维(SACF-Mn),并研究了制备条件对SACF-Mn的结构及表面形态的影响。研究表明:增大锰溶液的浓度,提高pH值,高价态的锰离子都有利于SACF对锰的吸附;锰化合物的阴离子类型,不仅影响SACF对锰的吸附,而且对载锰后SACF的表面形态的影响更显著。  相似文献   

8.
亚甲基蓝和Ag^+在活性炭纤维上的共吸附   总被引:7,自引:0,他引:7  
研究了水蒸汽活化和化学活化两类活性纤维(ACF)对水溶液中单组分亚甲基蓝和Ag(NH3)^+2以及两者共存时的吸附特征,ACF对水溶液中亚甲基蓝的吸附量主要取决于其表面积和孔分布,ACF对Ag^+的还原一吸附能力则主要取决其表面的化学性质,相同条件下,化学活化的ACF对银离子的还原吸附量(300mg.g^-1)比水蒸活化的ACF的还原-吸附量(100mg.g^-1)高,溶液中亚甲基蓝的存在显著改变  相似文献   

9.
聚苯胺/涤纶导电复合纤维的制备   总被引:5,自引:0,他引:5  
以涤纶(PET)为基材.采用就地氧化聚合吸附的方法制得PAN/PET导电复合纤维。结果表明,采用一定浓度的钒酸钠等含钒弱氧化剂,PET纤维预吸附苯胺单体等方法,可保证PET这类结构致密、疏水性强的纤维对聚苯胺的有效吸附。制得的导电纤维具有较好的导电性、物理力学性能及环境稳定性,其质量比电阻低于10Ωg/cm2。  相似文献   

10.
粗化是实现活化液在ABS表面吸附的前提和获得良好结合力的必要条件.采用含痕量钯离子的铬酐-硫酸粗化液对ABS塑料表面进行化学粗化,用AFM、XPS和胶体钯吸附量等对粗化前后塑料的表面性能、价键状态和活性进行了考察.结果表明:钯离子加入到粗化液中对ABS表面的粗糙度影响不显著,粗化后的表面氧含量升高;随着粗化液中钯离子浓度的增加,胶体钯在ABS表面上的吸附量增加;增加粗化液中的Pd含量可使ABS表面在低浓度胶体钯溶液中达到与高浓度钯相同的吸附量,有效地降低了胶体钯的浓度.粗化液中加入钯离子不影响基体与镀层的结合力.  相似文献   

11.
A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.  相似文献   

12.
The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……  相似文献   

13.
Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.  相似文献   

14.
We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.  相似文献   

15.
Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.  相似文献   

16.
ABSTRACT

The production of iron in Biscay (Basque Country, Spain) has been a hallmark of this territory of the North of the Iberian Peninsula throughout its history. The Archaeology team of the Basque Country Mining Museum has spent 13 years, so far, studying the origins of this activity through the evidences left at the old pre-hydraulic iron production workshops known as mountainside ironworks (ferrerías de monte) or haizeolak. It has catalogued 170 archaeometallurgical sites of this type in Biscay, and the archeological excavation of some of them has led to the knowledge of the different stages of the production process that took place in these workshops. The team has also experimentally reproduced the work carried out in a mountainside ironworks from the High Middle Ages, and it has currently started the characterization process of this type of activity through the study of the collected materials.  相似文献   

17.
As demands about environment protection are growing up, dry cutting technology is getting more and more concerns from all over the world. Main works performed here are study on dry cutting performances and wear mechanisms of M2high-speed steel (HSS) twist drills with CrAlTiN multicomponent coatings, which was deposited using magnetron sputter ion plating system, in drilling 45 and 30CrMnSiA steel, and their comparisons to those in drilling the same steel but using monolayer CrN and commercial TiN coated drills. Drilling performances of drills are evaluated mainly through the measurements of width on outer corner flank land and the cutting forces. Results show that performances of CrAlTiN coated drills are better than those of monolayer CrN and TiN coated drills. In drilling 45 and 30CrMnSiA steel, the average tool life of the CrAlTiN coated drills are 17.2 and 11.8 times higher than those of the uncoated drills. Observing wear of the drill with scanning electronic microscope, results show that there is no crack or spallation of the CrAlTiN coatings in wear zones. Main mechanism of the wear here is adhesion.  相似文献   

18.
Arc spraying coatings are widely used in various applications, but uncommon in cast iron substrate. Different surface pretreatment technology is tested on substrates of gray cast iron. Surface roughness and residual stress were measured by TR200 and X-ray diffraction analyzer. Influence of different surface pretreatment methods ( dry blasting and fusebond) on roughness and residual stress was analyzed. The arc-sprayed coatings of wire 3Cr13 (φ2mm) on gray cast iron substrate is studied. The microstructure and interface of bonding layer were observed by SEM. The bond strength was taken by tensile test. Results show that bond strength with grit blasting is higher than fuse-bond; it is feasible to make wire 3Cr13 coating with arc spraying on cast iron substrate roughened by grit blasting.  相似文献   

19.
TiO2 ceramic coatings with thickness of 20 μm were formed on the surface of pure titanium by micro-plasma oxidation. Their micro-structures were investigated by by using X-ray diffraction and their surface images were detected by using scan electronic microscope. There were three kinds of TiO2 coatings, pure anatase type TiO2 phase, mixed phases consisted of rutile type TiO2 phase and anatase type TiO2 phase, pure rutile type TiO2 phase. The coating surface with the pure anatase type TiO2 phase is rough, while the coating surface with the pure rutile type TiO2phase is smooth. The upper coating surface with the mixed type TiO2 phases is anatase type TiO2 structure and the subsurface of the TiO2 coating is rutile type TiO2structure.  相似文献   

20.
The insightful discussion of the relationship between the construction of metallographic and fatigue life and proposition of mathematical relationships describing this relationship was conducted in the paper. This paper presents a method for estimating the fatigue life, based on the construction of the microstructural material taking into account the grain size and the participation of ferrite and pearlite phase.  相似文献   

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