Nano Nickel-Cobalt Ferrite Catalysed One-Pot Multi-Component Synthesis of Xanthenediones and Acridinediones

1,8-Dioxo-octahydroxanthenes (4a-4f) and 1,8-dioxohexahydroacridines (5a-5c) were synthesized by novel, simple and eco-friendly method with higher yields in the presence of magnetically separable nano nickel-cobalt ferrite catalyst (Ni0.5Co0.5Fe2O4). The former, 1,8-dioxo-octahydroxanthenes have been synthesized from dimedone and different aromatic aldehydes, while the latter from this mixture are along with ammonium acetate. The main advantage of this method is that the nano catalyst can be reused up to five reaction cycles without losing the catalytic activity.

Carbon dioxide catalytic conversion to nano carbon material on the iron–nickel catalysts using CVD-IP method

The over-consumption of fossil fuels resulted in the large quantity emission of carbon dioxide （CO2）, which was the main reason for the climate change and more extreme weathers. Hence, it is extremely pressing to ex- plore efficient and sustainable approaches for the carbon-neutral pathway of CO2 utilization and recycling. In our recent works with this context, we developed successfully a novel ＂chemical vapor deposition integrated process （CVD-IP）＂ technology to converting robustly CO2 into the value-added solid-form carbon materials, The monometallic FeNi0-Al2O3 （FNi0） and bimetallic FeNix-Al2O3 （FNi2, FNi4, FNi8 and FNi20） samples were synthesized and effective for this new approach. The catalyst labeled FNi8 gave the better performance, exhibited the single pass solid carbon yield of 30%. These results illustrated alternative promising cases for the CO2 capture utilization storage （CCUS）, by means of the CO2 catalytic conversion into the solid-form nano carbon materials.

基于中空氧化镍纳米微球和离子液体复合膜固定血红蛋白的NaNO_2生物传感器

采用微波水热法合成了一种中空氧化镍纳米微球(NiO),然后将其与1-丁基-3-甲基-咪唑四氟硼酸盐(BMIMBF4)的复合膜用于血红蛋白(Hb)在碳糊电极上的固定,制备了NaNO2生物传感器.通过扫描电子显微镜、傅里叶变换红外光谱及紫外-可见光谱等分析表明,Hb已固定于NiO和BMIMBF4的复合膜中并能保持其生物活性;进一步通过电化学阻抗法研究了修饰电极中混合物各组分的作用.结果表明,在NiO和BMIMBF4的复合膜中,Hb能实现有效的直接电子转移,且修饰后的电极对NaNO2有良好响应,响应时间小于5 s,检出限为4.57μmol/L(S/N=3),灵敏度为46.2μA.L.mmol-1,线性范围为10～170μmol/L,表观米氏常数KM为2.4 mmol/L,该方法的重现性和电极的稳定性良好.

乙二胺四乙酸改性对NiMo/Nano-HZSM-5催化剂脱硫性能的影响

以水热处理的纳米HZSM-5为载体,通过螯合剂乙二胺四乙酸(EDTA)改性制备了一种具有较高脱硫活性和稳定性的EDTA-NiMo/HZSM-5催化剂,并用XRD,ICP,FTIR,27Al MAS NMR,TG-DTA,Py-IR及NH3-TPD等手段对催化剂进行了表征.结果表明,EDTA与载体之间具有较强的相互作用,这种强相互作用减弱了金属活性组分与载体之间的作用力,抑制了非活性NiAl2O4和Al2(MoO4)3的形成,有利于活性组分在载体表面的分散,并且添加的螯合剂与金属组分镍可以形成稳定的螯合物,在硫化过程中能改变催化剂的硫化顺序,促使有效脱硫活性中心的形成,提高了催化剂的脱硫活性和稳定性.

Effect of Ni,Fe and Fe-Ni alloy catalysts on the synthesis of metal contained carbon nano-onions and studies of their electrochemical hydrogen storage properties

Three types of carbon nano-onions（CNOs） including Ni@CNOs.Fe3C@CNOs and Fe0.64Ni0.36@CNOs nanoparticles have been synthesized by catalytic decomposition of methane at 850 ℃ using nickel,iron and iron-nickel alloy catalysts.Comparative and systematic studies have been carried out on the morphology,structural characteristics and graphitic crystallinity of these CNOs products.Furthermore,the electrochemical hydrogen storage properties of three types of CNOs have been investigated.Measurements show that the Ni@CNOs have the highest discharge capacity of 387.2 mAh/g,coiTesponding to a hydrogen storage of 1.42%.This comparison study shows the advantages of each catalyst in the growth of CNOs.enabling the controllable synthesis and tuning the properties of CNOs by mediating different metals and their alloy for using in the fuel cell system.

Ni catalysts supported on nanosheet and nanoplate γ-Al_2O_3 for carbon dioxide methanation

Nanosheet(S) and nanoplate(P) γ-Al_2O_3 were synthesized by simple hydrothermal methods and employed as supports for Ni catalysts in CO_2 methanation.Both of the nanostructured Ni/Al_2O_3 catalysts displayed good activity.In comparison,the Ni/Al_2O_3-S catalyst showed higher CO_2 conversion than the Ni/Al_2O_3-P counterpart at the reaction temperature ranging from 250 to 400 °C.The physical and chemical properties of the catalysts were systematically characterized by N2 sorption,X-ray diffraction(XRD),high resolution-transmission electron microscopy(HR-TEM),hydrogen temperature-programmed reduction(H2-TPR) and CO_2 temperature-programmed desorption(CO_2-TPD) techniques.Higher specific surface area and stronger metal-support interactions were confirmed on the Ni/Al_2O_3-S catalyst,which may lead to smaller particle size of Ni nanoparticles.Moreover,the Ni/Al_2O_3-S catalyst possessed more abundant weak and medium basic sites,which would benefit the activation of CO_2.The smaller Ni size and more suitable basic sites may rationalize the superior activity of the Ni/Al_2O_3-S catalyst.Besides,the Ni/Al_2O_3-S catalyst exhibited excellent stability at 325 °C for 40 h.

Vertically aligned NiS nano-flakes derived from hydrothermally prepared Ni(OH)2 for high performance supercapacitor

In present work,the vertically aligned Ni S nano-flakes composed thin film is prepared by anionic exchange process in which hydrothermally prepared Ni（OH）2is used as a parent thin film and Na2S as a sulfide ion source.This synthesis process produced fully transformed and shape-controlled nano-flakes of Ni S from nano-flowers of Ni（OH）2.The electrochemical supercapacitor properties of Ni S electrode are studied with cyclic voltammetry（CV）,galvonostatic charge discharge（GCD）and electrochemical impedance spectroscopy（EIS）techniques.Highly porous surface area（85 m^2/g）of Ni S nano-flakes makes large material contribution in electrochemical reaction stretching specific capacitance（Cs）of 880 F/g at scan rate of 5 m V/s and 90%electrochemical stability up to 4000 CV cycles in 2 M KOH electrolyte.Further,the flexible solid-state symmetric supercapacitor device（Ni S/PVA–Li ClO4/Ni S）has been fabricated using Ni S electrodes with polyvinyl alcohol（PVA）–lithium perchlorate（Li ClO4）gel electrolyte.The Ni S/PVA–Li ClO4/Ni S device exhibits specific capacitance of 56 F/g with specific energy of 14.98 Wh/kg and excellent cycling stability after 2000 cycles.In addition,the Ni S/PVA–Li ClO4/Ni S device demonstrates illumination of red light emitting diode（LED）for 60 s,which confirms the practical applicability of Ni S/PVA–Li ClO4/Ni S device in energy storage.

Nano-SiO_(2)和镍渣掺量对碱矿渣砂浆强度和自收缩的影响

为改善碱矿渣砂浆自收缩大的缺陷,将Nano-SiO_(2)和镍渣掺入其中,研究两者掺量对抗折强度、抗压强度和自收缩的影响。研究结果表明:在镍渣掺量一定时,随着Nano-SiO_(2)掺量的增加强度值先提高后降低,掺量为1%时强度值最高,对强度的提高幅度也最大;当Nano-SiO_(2)掺量一定时,随着镍渣掺量的增加强度值逐渐降低,掺量为30%时强度降低幅度最小;当镍渣掺量为30%,随着Nano-SiO_(2)掺量的增加,自收缩值先降低后提高,掺量为1%时,自收缩值最小,对自收缩的降低幅度也最大;当Nano-SiO_(2)掺量为1%时,随着镍渣掺量的增加自收缩值逐渐降低,掺量为30%时降低幅度最大。

New Nano-Film Single-Rivet Patent Ductus Arteriosus Occluders:A Prospective,Randomized and Double-blind Study

Nitinol alloy occluders are widely used in the transcatheter intervention treatment of congenital heart diseases like patent ductus arteriosus（PDA）.However,nitinol alloy contains high levels of nickel,which can lead to toxic effects in the immune and hematopoietic systems if released in sufficient quantities.A new type of single-rivet occluder coated with nano-film has been developed to limit the release of nickel.In total,23 patients were recruited and randomly assigned to the experimental group（n=12） with the new nano-film single-rivet occluders or the control group（n=11） with the traditional occluders.One case in the control group was lost to follow-up.The remaining 22 cases were followed up at 24 h,7 days,1 month,3 months,and 6 months after the procedure.There were no statistically significant differences in routine blood test,alanine aminotransferase,creatinine,and troponin between the experimental and control groups.Serum nickel concentration in both two groups increased at 24 h after the procedure,peaked at 1 month,and returned to preoperative levels at 6 months.Serum nickel levels in the experimental group were significantly lower than in the control group at 24 h,7 days,1 month,and 3 months after the procedure.These data suggested that the nano-film coating effectively prevented nickel release from the new occluders,and therefore has a preferable safety profile.

Trace analysis of mefenamic acid in human serum and pharmaceutical wastewater samples after pre-concentration with Ni-Al layered double hydroxide nano-particles

In this work, the nickel-aluminum layered double hydroxide （Ni-Al LDH） with nitrate interlayer anion was synthesized and used as a solid phase extraction sorbent for the selective separation and pre-concentration of mefenamic acid prior to quantification by UV detection at λmax ？ 286 nm. Extraction procedure is based on the adsorption of mefenamate anions on the Ni-Al（NO3？ ） LDH and/or their exchange with LDH interlayer NO3？ anions. The effects of several parameters such as cations and interlayer anions type in LDH structure, pH, sample flow rate, elution conditions, amount of nano-sorbent and co-existing ions on the extraction were investigated and optimized. Under the optimum conditions, the calibration graph was linear within the range of 2-1000 mg/L with a correlation coefficient of 0.9995. The limit of detection and relative standard deviation were 0.6 mg/L and 0.84% （30 mg/L, n ？ 6）, respectively. The presented method was successfully applied to determine of mefenamic acid in human serum and pharmaceutical wastewater samples.

Effect of tension deformation on microstructure and mechanism of electrodeposited nickel coating

Nickel coating deposits with better ductility on a lower carbon steel sheet were produced by electrodeposition method and the electrodeposited nickel coating was deformed with the strain of 10%. Then the surface morphology,the deformation texture and the mechanical properties were analyzed by scanning electron microscopy(SEM),X-ray diffractometry(XRD) and nano-indentation measurement,respectively. The principle of nano-indentation to measure the hardness and elastic modulus of nickel coating was introduced. The relation curves of the load and displacement were obtained,including the original electrodeposited samples and the samples under tension. The results show that:1) there are only two main texture components Ni(111) and Ni(200) in the nickel coating,and no new texture component is found due to the elongation;2) after tensile deformation in the coating,the surface roughness increases and the microcrack is found;3) The hardness and the elastic modulus decrease after tensile deformation;and 4) for the original electrodeposited sample,the indentation depths change with the load,the hardness and the elastic modulus decrease with the increase of the depth. In addition,the investigation of creep shows that the value of creep increases when the tensile strain ε>10%.

The Study of Structural and Magnetic Properties of NiO Nanoparticles

Nickel Oxide (NiO) is an important transition metal oxide with cubic lattice structure. Among the magnetic nanoparticles, fabrication of nickel nanoparticles is often more difficult than that of the other particles. This is because they are easily oxidized. To achieve pure nickel nanocrystals, numerous methods have been conducted in organic environments in order to prevent formation of hydroxide or oxidation. In the present work, we report the synthesis of NiO nanoparticles. Magnetic properties of NiO nanoparticles with different sizes and at different temperatures are compared. The phase structures, particle sizes and magnetic properties of NiO nanoparticles have been characterized by X-ray diffraction, TEM images and Vibrating Sample Magnetometer (VSM). We collected the experimental data reported in the literature, for the same conditions, and after fitting, extrapolating and doing some calculations. The magnetization for smaller nanoparticles is bigger for the samples we consider here. This difference could be explained by the difference of surface volume ratio of nanoparticle which shows the contribution of the paramagnetic surface is more important with respect to the anti-ferromagnetism of the core for smaller particles. Also the nanoparticle at lower temperatures shows bigger magnetization.

Effect of Laser Texturing Parameters on Wettability of Nickel Surface

Wettability is an important characteristic of solid surfaces. Enhancing the surface wettability is very important for improving the properties of materials. Superhydrophobic materials show good prospects for development in areas such as self-cleaning, anti-fog snow, anti-icing, and corrosion resistance. It has become a hot spot to develop a superhydrophobic surface with low surface free energy and good anti-adhesion properties. In this paper, nanosecond pulsed lasers were used to texture the nickel surface, and the different texturing speeds were changed. Combined with the ultrasonic treatment of low surface energy materials, nickel surfaces with different contact angles were obtained. The experimental results show that low surface energy substances can increase the contact angle of nickel surface but the extent of increase is limited. Laser microstructure induces micro & nanostructures. Ultrasonic action can adsorb certain low surface energy substances on the surface, greatly improving the hydrophobic properties of the surface, the contact angle with water up to 152? and the roll angle is less than 2?, and with the increase of the laser texturing speed, the contact angle of the nickel surface shows a decreasing trend.

纳米TiC浓度对双脉冲电沉积Ni-TiC复合镀层结构及性能的影响

研究了镀液中纳米TiC的添加量对双脉冲电沉积Ni-TiC复合镀层结构及性能的影响。通过扫描电镜(SEM)和X射线衍射(XRD)对镀层的表面形貌和物相进行了表征,并研究了镀层的表面粗糙度、显微硬度、耐磨性能和耐腐蚀性能。结果表明:当镀液中TiC浓度较低时,复合镀层表现为类似于纯Ni镀层的胞状沉积结构。当镀液中TiC浓度较高时,复合镀层表现为菜花状沉积结构。当纳米TiC浓度为8 g/L时,镀层表面致密性相对较高,Ni的衍射峰有明显的宽化现象。随着镀液中纳米TiC浓度的升高,复合镀层的磨损质量损失比表现为先下降后上升的趋势,当TiC浓度为8 g/L时,磨损质量损失比最小,为5.436%。当镀液中纳米TiC浓度为8 g/L时,镀层的自腐蚀电流密度最小,极化电阻值最大。结果表明双向脉冲电沉积制备Ni-TiC复合镀层镀液中最佳纳米TiC浓度为8 g/L。

Microstructures and mechanical properties of nanocrystalline NiTi intermetallics formed by mechanosynthesis

The formulation of nanocrystallinc NiTi shape memory alloys has potential effects in mechanical stimulation and medical im- plantology. The present work elucidates the effect of milling time on the product＇s structural characteristics, chemical composition, and mi- crohardness for NiTi synthesized by mechanical alloying for different milling durations. Increasing the milling duration led to the formation of a nanocrystalline NiTi intermetallic at a higher level. The formation of nanocrystalline materials was directed through cold fusion, fractur- ing, and the development of a steady state, which were influenced by the accumulation of strain energy. In the morphological study, uninter- rupted cold diffusion and fracturing were visualized using transmission electron microscopy. Particle size analysis revealed that the mean particle size was reduced to -93 μm after 20 h of milling. The mechanical strength was enhanced by the formation of a nanocrystalline in- termetallic phase at longer milling time, which was confirmed by the results of Vickers hardness analyses.

基于ENEPIG镀层的无压纳米银膏烧结失效分析

总结了在化学镍钯浸金(ENEPIG)镀层上采用纳米银膏进行无压烧结时出现的失效模式。通过分析烧结镀层的微观形貌及力学性能,确认界面污染、烧结不充分及镀层缺陷是导致烧结失效的主要原因。应特别关注镍原子向镀层表面扩散导致的烧结失效风险。为保证烧结质量的稳定性和可靠性,需要充分重视界面的洁净度,对芯片、基板的存储条件和存储寿命实施严格管控,还需要优化烧结曲线,充分考虑溶剂释出所需时间、烧结峰值温度及其停留时间、降温速率等因素。研究结果为纳米银膏的无压烧结研究提供了新的理论参考。

维生素B_(12)改性纳米零价镍去除溶液中U(Ⅵ)的机理

采用液相还原法制备了维生素B_(12)改性的纳米零价镍(VB_(12)@nZVNi),运用SEM-EDS、Zeta、XPS对材料进行表征,研究其形貌特征,并对VB_(12)@nZVNi去除U(Ⅵ)的机理进行等温吸附、动力学与热力学研究。动力学研究结果表明,VB_(12)@nZVNi对U(Ⅵ)的去除包括吸附和还原两种方式,其吸附过程很好地符合准二级吸附动力学模型和Langmuir等温吸附模型,理论最大吸附容量高达670.6 mg/g。热力学研究结果表明,该反应是自发进行的吸热反应,吸附过程是物理吸附与化学吸附并存,为表面单层吸附且离子间没有相互作用。还原反应符合准一级还原动力学模型,维生素B_(12)中的Co可促进Ni^(0)对U(Ⅵ)的还原。VB_(12)@nZVNi材料的合成方法简便、环境友好、去除效果好,在含U(Ⅵ)废水处理中具有较好的应用前景。

SiC芯片封装纳米银烧结层的热机械分析及疲劳寿命预测

纳米银的热膨胀系数与模块中其他组件存在较大差异,导致在严苛环境下工作时发生热疲劳失效。因此,预测纳米银烧结层的热疲劳寿命成为关键问题。以SiC功率模块为对象,利用有限元仿真和修正的Coffin-Manson寿命预测模型,分析了纳米银烧结层在热循环载荷下的最大等效应力和疲劳寿命。进一步通过响应面法分析,以疲劳寿命为优化目标,选取了SiC芯片和纳米银烧结层最佳参数组合,并探究铜基板镀镍对疲劳寿命的影响。研究结果显示:在累积的热循环下,纳米银烧结层边角处的等效应力最大,最容易发生热疲劳失效。通过优化设计,当SiC芯片厚度取0.15 mm,纳米银烧结层厚度取0.1 mm时,最大等效应力降低了1.36%,疲劳寿命增加了1.57倍。此外,铜基板上的镍层与纳米银烧结层具有相适应的材料属性,能够降低纳米银烧结层的等效应力,并增加其疲劳寿命。

Ni–MgO核–壳纳米粉体的制备

采用包覆热分解烧结法,制备了多层陶瓷电容器内部电极用MgO包覆Ni纳米粉体,讨论了反应物浓度和分散剂含量对包覆纳米镍盐前驱体颗粒大小和均匀性的影响,分析了还原烧结温度对包覆纳米Ni粉球形度和分散性的影响,并利用X射线衍射仪、扫描电镜、透射电镜、热机械分析仪对MgO包覆纳米Ni粉进行了表征分析。结果表明:反应物浓度达到足以引起反应爆炸成核时,能够获得纳米镍盐颗粒;添加适量的分散剂,可以得到分散良好的纳米镍盐前驱体颗粒;还原烧结温度700℃时,可以获得球形度和分散性良好的MgO包覆纳米Ni粉;MgO包覆在纳米Ni粉表面,形成了核壳结构,该纳米Ni粉具有良好的收缩延迟效果。