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《电镀与涂饰》2016,(21)
采用脉冲电沉积法在碳素工具钢表面制备Cu-Sn-Ni-PTFE复合镀层。镀液配方和工艺为:K_4P_2O_7·3H_2O 266.5 g/L,Cu_2P_2O_7·4H2O 20 g/L,NiSO_4·4H_2O 0.06~0.14 mol/L,KNaC_4H_4O_6·4H_2O 31.6 g/L,Na_2SnO_3·3H_2O 40 g/L,KNO_3 40 g/L,Na_3C_6H_5O_7·2H_2O 20 g/L,PTFE 10 g/L,pH 9.5~10.0,温度35~40℃,电流密度2.5 A/dm~2,脉冲频率3 000 Hz,占空比60%,转速100 r/min,时间1 h。研究了镀液中Ni~(2+)浓度对复合镀层表面形貌、组成、显微硬度及摩擦磨损性能的影响。结果表明,镀液中Ni~(2+)浓度为0.1 mol/L时,Cu-Sn-Ni-PTFE镀层表面均匀、致密,显微硬度高达391 HV,耐磨性最好。 相似文献
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针对稀土永磁体温度稳定性较差,利用双向脉冲电沉积法在钕铁硼永磁体上电沉积Fe-Ni-Co合金.镀液组成和操作条件为:FeSO4·7H2O 40 g/L,CoSO4·7H2O 1 g/L,NiSO4·7H2O120 g/L,NiCl2·6H2O 25 g/L,H3BO3 40 g/L,乳酸20 mL/L,抗坏血酸20 g/L,糖精2 g/L,柠檬酸钠80 g/L,十二烷基硫酸钠0.01 g/L,乙二醇20 mL/L,pH=3,温度60~65℃.通过扫描电镜和X射线衍射考察了合金镀层形貌及结构,采用划痕法和中性盐雾试验分别测试了合金镀层的结合力和耐蚀性.实验结果表明,制得的合金镀层表面较均匀致密,结合力好,耐蚀性强.磁性能测试表明该合金镀层有一定的温度补偿作用. 相似文献
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通过复合电刷镀在20钢基体表面制备镍铁–立方氮化硼(CBN)复合镀层。研究了施镀电压、镀液温度及镀笔速率对复合镀层中CBN含量的影响,分析了镀层中CBN含量与耐磨性之间的关系。复合电刷镀NiFe–CBN的镀液组成和最佳工艺条件为:NiSO4·6H2O 270~300 g/L,FeCl2·2H2O 23~27 g/L,H3BO326~30 g/L,Na3C6H5O7·2H2O 20~30 g/L,糖精2~3 g/L,十六烷基三甲基溴化铵0.2~0.3 g/L,pH 3.2~4.0,电压14 V,温度50°C,镀笔速率15 m/min,时间100~120 min。在最佳工艺下所得镀层的CBN质量分数为9.8%,显微硬度为770 HV,耐磨性和结合力良好。 相似文献
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以紫铜片为基体电沉积制备了Ni–Fe–W合金电极。研究了镀液中不同组分的浓度和工艺条件对Ni–Fe–W合金析氢性能的影响,得到最佳镀液配方和工艺条件为:NiSO4·6H2O80g/L,FeSO4·7H2O20g/L,Na2WO4·2H2O0.020mol/L,Na3C6H5O7·2H2O 0.5 mol/L,H3BO3 0.65 mol/L,Na2SO4 0.1 mol/L,十二烷基硫酸钠0.1 g/L,pH 5~6,温度30°C,电流密度4 A/dm2,磁力搅拌800 r/min,时间30 min。在该条件下所得Ni–Fe–W合金电极表面Ni、Fe和W的原子分数为63.79%、34.35%和1.86%,具有较大的比表面积,在30%KOH溶液中的析氢催化活性较好。 相似文献
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工艺参数对电镀镍铜合金镀层成分及相结构的影响 总被引:1,自引:0,他引:1
采用由200 g/L NiSO4·6H2O、10 g/L CuSO4·5H2O、80 g/L Na3C6H5O7·2H2O、0.2 g/L C12H25SO4Na和0.5 g/L糖精钠组成的镀液,在10~60 mA/cm2、pH=2.5~5.0和25~50°C条件下电沉积制备了NiCu合金镀层。探讨了镀液pH、电流密度、温度等工艺参数对镍铜合金镀层相结构和组成的影响。结果表明,NiCu合金镀层的铜含量随电流密度或温度升高而增大。但随pH增大,镀层铜含量降低,pH小于4.0时,NiCu合金镀层中含有单质铜。 相似文献
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采用正交试验对化学镀镍–磷合金镀液的添加剂进行优化。基础镀液组成和工艺条件为:NiSO4·6H2O26 g/L,NaH2PO2·H2O 30 g/L,CH3COONa·3H2O 16 g/L,柠檬酸21.5 g/L,88%乳酸5 m L/L,OP-10 5 mg/L,p H 4.80±0.2,温度(88±2)°C,时间2 h。探讨了添加剂苯骈三氮唑(BAT)、苯并咪唑(BMI)、氨三乙酸(NTA)和硫酸高铈对镀速、镀层光泽度和磷含量的影响。4种添加剂的最优组成为:BAT 1.0 mg/L,BMI 10 mg/L,NTA 0.5 g/L,Ce(SO4)2·4H2O 6 mg/L。采用该组合添加剂进行化学镀Ni–P合金时,镀速为10.92μm/h,镀层光泽度和磷含量分别为225 Gs和12.96%,表面均匀、致密、平整。 相似文献
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乙烯酮(双乙烯酮)是十分重要的化工中间体,其下游产品较多。江苏某化工厂开发生产乙烯酮(双乙烯酮)下游产品三十多个,年生产规模三万多吨,是国内以乙烯酮(双乙烯酮)为中间体生产精细化学品的综合骨干企业。针对乙烯酮(双乙烯酮)下游产品废水特点,该厂结合企业实际,开展了产品优化,结构调整,清洁生产,资源循环利用,节水降耗等工作,从源头削减了污染物的生产。同时投资二千多万元新建预处理装置三套,6000m3/d废水生化处理装置一套,使全厂乙烯酮(双乙烯酮)下游产品的废水得到了有效的治理。 相似文献
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D. G. Gordeev L. F. Gudarenko M. V. Zhernokletov V. G. Kudel’kin M. A. Mochalov 《Combustion, Explosion, and Shock Waves》2008,44(2):177-189
A semi-empirical equation of state for metals is described. Its capabilities are demonstrated by the example of the equation
of state for aluminum. New experimental data are presented on the location of the isentrope of aluminum for unloading from
the state at p = 229.71 GPa on the shock adiabat to an aerogel (SiO2) of density 0.08 g/cm3.
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Translated from Fizika Goreniya i Vzryva, Vol. 44, No. 2, pp. 61–75, March–April, 2008. 相似文献
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The objective of the study was to explore the effect of the degree of deacetylation (DD) of the chitosan used on the degradation rate and rate constant during ultrasonic degradation. Chitin was extracted from red shrimp process waste. Four different DD chitosans were prepared from chitin by alkali deacetylation. Those chitosans were degraded by ultrasonic radiation to different molecular weights. Changes of the molecular weight were determined by light scattering, and data of molecular weight changes were used to calculate the degradation rate and rate constant. The results were as follows: The molecular weight of chitosans decreased with an increasing ultrasonication time. The curves of the molecular weight versus the ultrasonication time were broken at 1‐h treatment. The degradation rate and rate constant of sonolysis decreased with an increasing ultrasonication time. This may be because the chances of being attacked by the cavitation energy increased with an increasing molecular weight species and may be because smaller molecular weight species have shorter relaxation times and, thus, can alleviate the sonication stress easier. However, the degradation rate and rate constant of sonolysis increased with an increasing DD of the chitosan used. This may be because the flexibilitier molecules of higher DD chitosans are more susceptible to the shear force of elongation flow generated by the cavitation field or due to the bond energy difference of acetamido and β‐1,4‐glucoside linkage or hydrogen bonds. Breakage of the β‐1,4‐glucoside linkage will result in lower molecular weight and an increasing reaction rate and rate constant. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 3526–3531, 2003 相似文献
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Jorge Marcelo Romero Soledad Bustillo Hugo Enrique Ramirez Maisuls Nelly Lidia Jorge Manuel Eduardo Gómez Vara Eduardo Alberto Castro Alicia H. Jubert 《International journal of molecular sciences》2007,8(7):688-694
A thermochemical rather simple experimental technique is applied to determine the enthalpy of formation of Diperoxide of ciclohexanone. The study is complemented with suitable theoretical calculations at the semiempirical and ab initio levels. A particular satisfactory agreement between both ways is found for the ab initio calculation at the 6–311G basis This set level. Some possible extensions of the present procedure are pointed out. 相似文献
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醋酸纤维素取代基分布与性质的关系 总被引:9,自引:0,他引:9
分析了以吡啶为溶剂的醋酸纤维素的13C-NMR核磁共振谱,得出了三种不同位置羟基的取代度。结合X—射线和DSC分析,初步说明具有相同取代度但未经水解和经过水解的醋酸纤维素(CA) 性质上的差异是由于三个羟基上的取代度分布不同及消晶程度差异所致。 相似文献