In this paper the mass transfer behaviors of Fe(Ⅲ), Co(Ⅱ) and Ni(Ⅱ) with Cyanex302(bis(2,4,4- trimethylpentyl)monothiophosphinic acid) from sulfate medium by using hollow fiber membrane in counter-currently circula...In this paper the mass transfer behaviors of Fe(Ⅲ), Co(Ⅱ) and Ni(Ⅱ) with Cyanex302(bis(2,4,4- trimethylpentyl)monothiophosphinic acid) from sulfate medium by using hollow fiber membrane in counter-currently circulating operation were studied. The effect of acidity in aqueous solution and the extractant concentration on the mass transfer coefficient (Kw) was discussed. The reaction mechanism of membrane extraction was considered as a false one series reaCtion and the rate controlling step was membrane resistance. When the value of Kw arrived at 1.0 × 10-6 m/s, △pH:CoFe equaled tO 6.225, and △pH:NiFe was bigger than △p HCoFe.展开更多
The hardness variation of two kinds of alloys with 36 wt pct W content and 7/3, 9/1 Ni-to-Fe ratios during strain aging at 800℃ was studied. The microstructures of the aged alloys were analyzed by X-ray diffraction a...The hardness variation of two kinds of alloys with 36 wt pct W content and 7/3, 9/1 Ni-to-Fe ratios during strain aging at 800℃ was studied. The microstructures of the aged alloys were analyzed by X-ray diffraction and TEM. The results show that the strain aging hardness of W-Ni-Fe ternary alloy with 7/3 Ni-to-Fe ratio decreases monotonically with the increase of aging time. Under the same conditions, the hardness of 9/1 Ni-to-Fe ratio alloy decreases in the initial aging stage, but then increases as aging process goes on. X ray diffraction and TEM analysis show that there is not any precipitation depositing from the alloy with 7/3 Ni-to-Fe ratio during aging. The monotonic decrease in hardness of this alloy during aging process results from the recovery, recrystallization and solid solubility declining. In the alloy of 9/1 Ni-to-Fe ratio, the fine β phase precipitates dispersively during aging which hardens the alloy. The two different kinds of mechanisms (the softening one and the hardening one) dec展开更多
以CeO_2为载体,制备了负载型复合Ni Fe/CeO_2催化剂,用于乙二醇的水相重整制氢.利用N_2吸附脱附(N_2 adsorption-desorption)、X-射线衍射(XRD)和H2化学吸附(H_2 temperature program reduction)对催化剂的结构进行了表征,并考察了Ni/F...以CeO_2为载体,制备了负载型复合Ni Fe/CeO_2催化剂,用于乙二醇的水相重整制氢.利用N_2吸附脱附(N_2 adsorption-desorption)、X-射线衍射(XRD)和H2化学吸附(H_2 temperature program reduction)对催化剂的结构进行了表征,并考察了Ni/Fe摩尔比对乙二醇水相重整制氢效果的影响以及催化剂的可重复使用性.实验结果表明:在Ni_1Fe_2/CeO_2催化剂上的乙二醇水相重整制氢反应中,H_2选择性为89.27%,,乙二醇转化率为99.13%,,烷烃选择性为11.43%,;催化剂重复使用5次以后,仍然保持初始活性的65%,左右.展开更多
利用Fe Ni Al Co Ti多元扩散偶研究了界面处的α1+α2+(FeCo)2Ti三相在800℃下的相平衡,通过扩散偶界面两侧的相成分分析获知,Co在α2与α1相之间的分配比约为1 1,Ti在α2与α1相之间的分配比约为2 5.在Fe Ni Al合金中同时添加Co与Ti时...利用Fe Ni Al Co Ti多元扩散偶研究了界面处的α1+α2+(FeCo)2Ti三相在800℃下的相平衡,通过扩散偶界面两侧的相成分分析获知,Co在α2与α1相之间的分配比约为1 1,Ti在α2与α1相之间的分配比约为2 5.在Fe Ni Al合金中同时添加Co与Ti时,其在固溶体α2与α1相之间的分配特征与Fe Ni Al Co和Fe Ni Al Ti系中一样,Co与Ti在α2与α1相之间的分配比仍均大于1.展开更多
在铜基上化学镀Fe Ni P B四元合金,研究了FeSO4/(FeSO4+NiSO4)金属盐比值对沉积速率、镀层结构的影响,测试了镀层在不同介质中的电化学稳定性。结果表明,镀层沉积速率随FeSO4/(FeSO4+NiSO4)金属盐比值的增加先增后减,金属盐比值为0.5... 在铜基上化学镀Fe Ni P B四元合金,研究了FeSO4/(FeSO4+NiSO4)金属盐比值对沉积速率、镀层结构的影响,测试了镀层在不同介质中的电化学稳定性。结果表明,镀层沉积速率随FeSO4/(FeSO4+NiSO4)金属盐比值的增加先增后减,金属盐比值为0.5时,沉积速率达到极大值。镀层沉积速率影响镀层的结构,沉积速率增大,镀层出现非晶结构。镀层在不同介质溶液中的稳定性不同,在酸性介质中,由于镀层的溶解,电极电位向正方向移动;而在中性和碱性介质中,由于氧的扩散缓慢,体系的电极电位会随时间负移。展开更多
基金Supported by the National Natural Science Foundahon of China(No. 29771028, No. 29801004) and State Key Project of Fundamental
文摘In this paper the mass transfer behaviors of Fe(Ⅲ), Co(Ⅱ) and Ni(Ⅱ) with Cyanex302(bis(2,4,4- trimethylpentyl)monothiophosphinic acid) from sulfate medium by using hollow fiber membrane in counter-currently circulating operation were studied. The effect of acidity in aqueous solution and the extractant concentration on the mass transfer coefficient (Kw) was discussed. The reaction mechanism of membrane extraction was considered as a false one series reaCtion and the rate controlling step was membrane resistance. When the value of Kw arrived at 1.0 × 10-6 m/s, △pH:CoFe equaled tO 6.225, and △pH:NiFe was bigger than △p HCoFe.
基金This work was supported by the National Natural Science Foundation of China under grant No.59971007.
文摘The hardness variation of two kinds of alloys with 36 wt pct W content and 7/3, 9/1 Ni-to-Fe ratios during strain aging at 800℃ was studied. The microstructures of the aged alloys were analyzed by X-ray diffraction and TEM. The results show that the strain aging hardness of W-Ni-Fe ternary alloy with 7/3 Ni-to-Fe ratio decreases monotonically with the increase of aging time. Under the same conditions, the hardness of 9/1 Ni-to-Fe ratio alloy decreases in the initial aging stage, but then increases as aging process goes on. X ray diffraction and TEM analysis show that there is not any precipitation depositing from the alloy with 7/3 Ni-to-Fe ratio during aging. The monotonic decrease in hardness of this alloy during aging process results from the recovery, recrystallization and solid solubility declining. In the alloy of 9/1 Ni-to-Fe ratio, the fine β phase precipitates dispersively during aging which hardens the alloy. The two different kinds of mechanisms (the softening one and the hardening one) dec
文摘以CeO_2为载体,制备了负载型复合Ni Fe/CeO_2催化剂,用于乙二醇的水相重整制氢.利用N_2吸附脱附(N_2 adsorption-desorption)、X-射线衍射(XRD)和H2化学吸附(H_2 temperature program reduction)对催化剂的结构进行了表征,并考察了Ni/Fe摩尔比对乙二醇水相重整制氢效果的影响以及催化剂的可重复使用性.实验结果表明:在Ni_1Fe_2/CeO_2催化剂上的乙二醇水相重整制氢反应中,H_2选择性为89.27%,,乙二醇转化率为99.13%,,烷烃选择性为11.43%,;催化剂重复使用5次以后,仍然保持初始活性的65%,左右.
文摘利用Fe Ni Al Co Ti多元扩散偶研究了界面处的α1+α2+(FeCo)2Ti三相在800℃下的相平衡,通过扩散偶界面两侧的相成分分析获知,Co在α2与α1相之间的分配比约为1 1,Ti在α2与α1相之间的分配比约为2 5.在Fe Ni Al合金中同时添加Co与Ti时,其在固溶体α2与α1相之间的分配特征与Fe Ni Al Co和Fe Ni Al Ti系中一样,Co与Ti在α2与α1相之间的分配比仍均大于1.
文摘 在铜基上化学镀Fe Ni P B四元合金,研究了FeSO4/(FeSO4+NiSO4)金属盐比值对沉积速率、镀层结构的影响,测试了镀层在不同介质中的电化学稳定性。结果表明,镀层沉积速率随FeSO4/(FeSO4+NiSO4)金属盐比值的增加先增后减,金属盐比值为0.5时,沉积速率达到极大值。镀层沉积速率影响镀层的结构,沉积速率增大,镀层出现非晶结构。镀层在不同介质溶液中的稳定性不同,在酸性介质中,由于镀层的溶解,电极电位向正方向移动;而在中性和碱性介质中,由于氧的扩散缓慢,体系的电极电位会随时间负移。