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21.
Arvin Eskandari Marie Flamme Dr. Zhiyin Xiao Dr. Kogularamanan Suntharalingam 《Chembiochem : a European journal of chemical biology》2020,21(19):2854-2860
We report the anti-osteosarcoma and anti-osteosarcoma stem cell (OSC) properties of a nickel(II) complex, 1 . Complex 1 displays similar potency towards bulk osteosarcoma cells and OSCs, in the micromolar range. Notably, 1 displays similar or better OSC potency than the clinically approved platinum(II) anticancer drugs cisplatin and carboplatin in two- and three-dimensional osteosarcoma cell cultures. Mechanistic studies revealed that 1 induces osteosarcoma cell death by necroptosis, an ordered form of necrosis. The nickel(II) complex, 1 triggers necrosome-dependent mitrochondrial membrane depolarisation and propidium iodide uptake. Interestingly, 1 does not evoke necroptosis by elevating intracellular reactive oxygen species (ROS) or hyperactivation of poly ADP ribose polymerase (PARP-1). ROS elevation and PARP-1 activity are traits that have been observed for established necroptosis inducers such as shikonin, TRAIL and glutamate. Thus the necroptosis pathway evoked by 1 is distinct. To the best of our knowledge, this is the first report into the anti-osteosarcoma and anti-OSC properties of a nickel complex. 相似文献
22.
镁合金表面镀镍被广泛运用于镁合金工件防腐,而镀层的起泡和脱落严重影响工件的使用寿命。本实验以ZK60镁合金为研究对象,分析了不同工件基底表面质量对镀镍层性能的影响机制。研究表明:基底表面存在的划痕和点蚀坑会显著降低镀镍层质量,引起镀层的起泡和脱落。基底表面的划痕会被保留到镀镍层中,引发镀层变薄,应力集中等问题,增加镀层开裂的几率。点蚀坑中的杂质与镁基底有不同的电化学特性,会导致镀层减薄和结合不牢。因此,提高镁合金工件基底表面光洁度、清除基底表面点蚀坑是提高镁合金镀镍层性能的必要措施。 相似文献
23.
《中国有色金属学会会刊》2020,30(11):3016-3030
The microstructure and mechanical properties of Inconel 625 alloy fabricated by wire arc additive manufacturing process were evaluated under as-prepared and heat-treated conditions. A dendritic Ni-based solid solution phase along with (Nb, Ti)C carbide, Laves, and δ-Ni3Nb secondary phases were developed in the microstructure of the as-prepared alloy. Solution heat treatment led to the dissolution of Laves and Ni3Nb phases. In addition, dendrites were replaced with large columnar grains. Aging heat treatment resulted in the formation of grain boundary M23C6 carbide and nanometric γ″ precipitates. Hardness, yield and tensile strengths, as well as elongation of the as-prepared part, were close to those of the cast alloy and its fracture occurred in a transgranular ductile mode. Solution heat treatment improved hardness and yield strength and declined the elongation, but it did not have a considerable impact on the tensile strength. Furthermore, aging heat treatment caused the tensile properties to deteriorate and changed the fracture to a mixture of transgranular ductile and intergranular brittle mode. 相似文献
24.
Yong Jiao Xiaoting Xue Wenting An Paulo Srgio Barros Julio Wei Wang Guangming Yang Wei Zhou Si‐Dian Li 《国际能源研究杂志》2019,43(7):2501-2513
The use of low‐rank coal in a clean and efficient manner is a major challenge facing the current coal technology. A high‐sulfur coal with 4.5 wt% sulfur is chosen to examine the compatibility of the pristine coal and the purified contrast with a solid oxide fuel cell (SOFC) with nickel cermet anodes. Desulfurization of the pristine coal is performed by molten caustic leaching method with a removal ratio of 80%. Analyses of the physicochemical properties of coal samples indicate that the purified coal has a more favorable structure and higher Boudouard reactivity, which is suitable as a fuel for fuel cells. The assessment of electrochemical performance reveals that the purification treatment not only makes the peak power density of SOFCs improve from 115 to 221 mW cm?2 at 900°C but also extends their durability from 1.7 to 11.2 hours under a current density of 50 mA cm?2 at 850°C with a fuel availability increasing from 6.25% to 40%. The postmortem analyses show that far less deposited carbon and nickel sulfide are observed on the anode surface. The fuel‐based investigation reveals that the purified coal is a promising fuel for direct carbon fuel cells. 相似文献
25.
新型镍基镁渣催化重整松木热解挥发分焦油析出特性研究 总被引:2,自引:2,他引:0
采用过量浸渍法制备了镍基镁渣催化剂,并在小型气流床气化炉上开展了松木热解挥发分的催化重整研究。评估了煅烧/催化温度、镍含量和水碳比对焦油组分的影响,同时在不同煅烧/催化温度下与Ni/γ-Al2O3催化剂进行了裂解焦油性能的对比。采用比表面积测试(BET)、X射线衍射(XRD)、扫描电镜(SEM)和透射电镜(TEM)对催化剂进行了表征。结果表明,当镍含量为3%,煅烧/催化温度为800℃,水碳比为0.5时,镍基镁渣催化剂表现出最优异的催化裂解焦油能力:大幅度降低了重质多环芳烃的相对含量,并且焦油转化率达到95.69%,同时焦油露点温度降至40.2℃。XRD结果表明,Ni、Fe、Ca、Mg相互作用可以形成多种活性中心,进而协同提高催化剂活性。 相似文献
26.
M.A. Azmah Hanim C.K. Wei T.T. Dele-Afolabi O.S. Azlina 《Materialwissenschaft und Werkstofftechnik》2021,52(9):943-951
In this study, the mechanical performance of the rice husk ash-reinforced tin-0.7 copper composite solder was investigated. 0.01 wt.%, 0.05 wt.% and 0.1 wt.% of rice husk ash (RHA) were added to the solder matrix to prepare the composite solders. In order, to replace the costly electroless nickel immersion gold surface finish on the copper substrate, the effect of electroless nickel immersion silver (ENIAg) as the surface finish was studied. The differential scanning calorimetry (DSC) analysis showed that the composite solder exhibited lower melting temperature relative to the plain solder owing to the inclusion of rice husk ash. Shear strength analysis was carried out to investigate the influence of rice husk ash and electroless nickel immersion silver surface finish on the shear strength of the developed composite solders. The results proved that the rice husk ash failed to enhance the shear strength of tin-0.7 copper lead-free solder with the plain solder exhibiting the highest shear strength. 相似文献
27.
Microstructural and Tribological Behavior of Pulse Electroplated Nickel Barrier on Copper Conductors
Ashutosh Sharma 《摩擦学汇刊》2019,62(3):476-485
The microstructural, mechanical, and tribological behaviors of electroplated Ni on Cu conducting substrates have been investigated in this study. The microstructural studies were performed by X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM). The results showed that initially (111) with (220), (200) Ni texture components were predominant in the coating, and increasing the current density from 0.1 to 0.5 A/cm2 led to the development of a strong (111) texture. The presence of ultrafine grains coupled with a (111) Ni texture improved the coating microhardness and wear properties significantly. It was shown that with an increase in current density, wear resistance of the coatings improved significantly and the electrical resistivity increased due to the highly populated grain boundaries. 相似文献
28.
《International Journal of Hydrogen Energy》2022,47(90):38124-38133
The construction of a bifunctional electrocatalyst with excellent performance and low cost plays a key role in the application prospect of renewable energy. Herein, nickel sulfide/CoFe layered double hydroxide heterostructures on nickel foam (NiS/LDH/NF) have been constructed by using hydrothermal and electro-deposition methods. The amorphous nickel sulfide is deposited on the surface of crystalline LDH mesh-like nanosheets to form a hierarchical flower-like structure. The deposition of amorphous NiS can control the morphology and modulate the electronic structure of NiS/LDH/NF. The obtained NiS/LDH/NF is employed as a bifunctional catalyst for overall water splitting, which can achieve a current density of 10 mA cm?2 at a low voltage of 1.51 V in 1 M KOH. The results show that the high electrocatalytic activity is ascribed to the formation of amorphous NiS/crystalline LDH heterostructure with abundant surface defects and active sites. The synthetic strategy holds a great promise for accelerating the development of hydrogen energy by highly efficient electrocatalytic production of hydrogen. 相似文献
29.
镀镍层对手汗渍非常敏感,容易形成汗渍性指纹腐蚀。经过试验研制了镀镍层专用的水性LP-1068C和溶剂型SP-2068C防汗渍性指纹的电接触润滑保护剂。其作用是防止钢铁和铝基体腐蚀,保护镀层不失光泽,并能充当镀镍后脱水材料,同时保持和保护镀镍层固有的电气性能。试验表明:只有使用具有协同效应的保护材料,才能起到防汗渍性指纹的保护作用。 相似文献
30.