Self-Bias Response of Lead-Free (1−x)[0.948 K0.5Na0.5NbO3-0.052 LiSbO3]-xNi0.8Zn0.2Fe2O4-Nickel Magnetoelectric Laminate Composites
摘要:
This study reports the magnetoelectric (ME) response of lead‐free particulate composites given as (1−x)[0.948 K0.5Na0.5NbO3–0.052 LiSbO3]–xNi0.8Zn0.2Fe2O4 (KNNLS–NZF) and bimorph laminates given as KNNLS–NZF/Ni/KNNLS–NZF. The particulate ME composites were found to exhibit island–matrix microstructure as confirmed by scanning electron microscopy and elemental mapping. Detailed investigations were conducted on optimization of the magnitude of magnetic and piezoelectric properties by varying the sintering condition and NZF mole fraction. It was found that longitudinal piezoelectric strain coefficient d33 and electromechanical coupling factor kp decreased with increasing NZF concentration. On the other hand, the magnitude of saturation magnetization Ms, remnant magnetization Mr, magnetic permeability μ, and magnetostriction λ was found to increase with increasing NZF fraction. The composition 0.7 KNNLS–0.3 NZF sintered at 1060°C was found to exhibit d33 of 73 pC/N, Ms of 19 emu/g, and maximum ME coefficient αE of 20.14 mV/cm·Oe under Hac=1 Oe at 1 kHz. The bimorph laminates were fabricated by embedding Ni plate between (1−x)KNNLS–xNZF disks with varying electrical connections to achieve radial and bending modes. The radial mode laminates were found to exhibit typical ME response without any self‐bias effect with maximum αE of 261.3 mV/cm·Oe and high DC magnetic field sensitivity of 1 μT at 1 kHz. The bending mode laminates were found to exhibit self‐biased ME response whose magnitude and shape was dependent upon the NZF concentration.
一锅法合成三芳基-1 H-咪唑 的Ni 0.5 Zn 0.5 Fe 2 O 4纳米粒子的合成,表征和应用†
摘要:
在本研究中,制备了Ni 0.5 Zn 0.5 Fe 2 O 4作为高效多相催化剂,并通过IR,EDX,XRD和SEM分析对其进行了表征。Ni 0.5 Zn 0.5 Fe 2 O 4通过无溶剂条件下的一锅三组分反应成功地用于合成2,4,5-三芳基取代的咪唑。效率,通用性,高收率,反应曲线更清洁,产物分离容易,反应时间短和操作简便是这项研究的优势。
Dielectric and electrical characteristics of mechanically synthesized Ni-Zn ferrite nanoparticles
作者:A. Hajalilou、H. Mohamed Kamari、K. Shameli
DOI:10.1016/j.jallcom.2017.03.030
日期:2017.6
microstructure and properties of the samples in such a way that this effect sustained even after the completion of sintering process. Thus, the main goal of this study is to scrutinize the effect of sintering temperature in the 30-h-milled samples in different atmospheres on DC electrical resistivity and dielectric behavior of Ni-Znferrite samples. The results indicated that although electrical resistivity
摘要 采用高能行星式球磨机对Zn、NiO和Fe2O3粉末进行机械活化,合成了Ni-Zn铁氧体纳米颗粒。将在氩气、氧气和空气气氛中研磨 30 小时的样品压制成丸状和环形形状,并在 500 °C 至 900 °C 之间以 100 °C 的增量进行烧结。X 射线衍射图结果表明,在 500 °C 下烧结的所有样品中均形成具有立方尖晶石结构的单相 Ni-Zn 铁氧体。研磨气氛在样品的合成、微观结构和性能中起着关键作用,即使在烧结过程完成后,这种影响也能持续。因此,本研究的主要目的是仔细研究在不同气氛中研磨 30 小时的样品的烧结温度对 Ni-Zn 铁氧体样品的直流电阻率和介电行为的影响。结果表明,虽然电阻率降低,但介电行为,即常数、损耗和tanδ随着烧结温度的增加而增加。与其他样品相比,在氩气中研磨的样品在 500 °C 时的电阻率最高,为 1.2 × 106 Ωcm,介电常数和损耗最低(分别为 4
A comparative study of different concentrations of pure Zn powder effects on synthesis, structure, magnetic and microwave-absorbing properties in mechanically-alloyed Ni–Zn ferrite
the desired ferrite was formed after sintering the 30 h-milled powders at 500 °C. The average crystallite size decreased with increase in the Zn content. A DC electrical resistivity of the Ni–Znferrite, however, decreased with increase in the Zn content, its value was much higher than those samples prepared by the conventional ceramic route by using ZnO instead of Zn. This is attributed to smaller
摘要 在本研究中,使用Zn、Fe 2 O 3 和NiO 的粉末混合物制备不同组成的Ni 1− x Zn x Fe 2 O 4 ( x =0.36、0.5 和0.64) 纳米粉末。进行了带有后续热处理方法的高能球磨。XRD 结果表明,对于 Zn 含量,x = 0.64 的单相 Ni-Zn 铁氧体在研磨 30 小时后产生,而对于 Zn 含量,x = 0.36 和 0.5,在烧结 30 小时后形成所需的铁氧体在 500 °C 下 h 研磨的粉末。平均晶粒尺寸随着Zn含量的增加而减小。然而,Ni-Zn 铁氧体的直流电阻率随着 Zn 含量的增加而降低,其值远高于通过使用 ZnO 代替 Zn 的传统陶瓷路线制备的样品。这归因于通过使用 Zn 获得较小的晶粒尺寸。FT-IR 结果表明八面体和四面体位点在 350-700 cm -1 范围内有两个吸收带。VSM 结果表明,通过将 Zn 含量从 0.36 增加到
Novel hybrid Sr-doped TiO<sub>2</sub>/magnetic Ni<sub>0.6</sub>Zn<sub>0.4</sub>Fe<sub>2</sub>O<sub>4</sub> for enhanced separation and photodegradation of organics under visible light
Titanium dioxide (TiO2) has been intensively used as a photocatalyst for the degradation of organic pollutants in water, but is typically obstacle by a low efficiency, costly separation, limited visible light response, and poor recyclability.
Caesium carbonate supported on hydroxyapatite-encapsulated Ni<sub>0.5</sub>
Zn<sub>0.5</sub>
Fe<sub>2</sub>
O<sub>4</sub>
nanocrystallites as a novel magnetically basic catalyst for the one-pot synthesis of pyrazolo[1,2-b]phthalazine-5,10-diones
作者:Behrooz Maleki、Samaneh Barat Nam Chalaki、Samaneh Sedigh Ashrafi、Esmail Rezaee Seresht、Farid Moeinpour、Amir Khojastehnezhad、Reza Tayebee
DOI:10.1002/aoc.3288
日期:2015.5
A novel nanomagnetic basiccatalyst of caesiumcarbonatesupported on hydroxyapatite‐coated Ni0.5Zn0.5Fe2O4 magnetic nanoparticles (Ni0.5Zn0.5Fe2O4@HAP‐Cs2CO3) was prepared. This new catalyst was fully characterized using Fourier transform infrared spectroscopy, transmission and scanning electron microscopy, X‐ray diffraction and vibrating sample magnetometry techniques, and then the catalytic activity
Structural and magnetic properties of nano-crystalline Ni–Zn ferrites synthesized using egg-white precursor
作者:M.A. Gabal、Reda M. El-Shishtawy、Y.M. Al Angari
DOI:10.1016/j.jmmm.2012.02.112
日期:2012.7
formation of spinel cubic structure. The average crystallite size was calculated using line broadening in XRD patterns. Structural parameters like lattice constant, X-ray density, bond lengths and inter-cationic distance were determined from XRD data. TEM showed agglomerated particles with average size agreed well with that estimated using XRD. FT-IR spectra confirm the formation of spinel structure and
摘要 不同成分的纳米晶镍锌铁氧体;Ni 1− x Zn x Fe 2 O 4 ( x =0.0–1.0) 是通过涉及蛋清和金属硝酸盐的前体方法制备的。提出了一种适当的蛋清金属络合机制。进行差热分析-热重分析、X 射线衍射 (XRD)、透射电子显微镜 (TEM)、傅里叶变换红外光谱 (FT-IR)、振动样品磁强计和交流磁化率测量,以研究化学、结构和磁性Ni-Zn 铁氧体的方面。XRD证实了尖晶石立方结构的形成。使用 XRD 图中的线加宽计算平均微晶尺寸。结构参数,如晶格常数、X 射线密度、键长和阳离子间距离由XRD数据确定。TEM 显示平均尺寸的附聚颗粒与使用 XRD 估计的一致。FT-IR 光谱证实了尖晶石结构的形成,并进一步支持所提出的阳离子分布。发现锌含量对系统的磁性能有显着影响。磁性的变化可归因于阳离子化学计量及其在特定位点中的占有率的影响。