There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

Elements Of X Ray Diffraction

Journal of Applied physics,Vol.33 : 1962年に発表されたレオロジー関連の論文

One-dimensional (1D) metal-oxide nanostructures are ideal systems for exploring a large number of novel phenomena at the nanoscale and investigating size and dimensionality dependence of nanostructure properties for potential applications The construction and integration of photodetectors or optical switches based on such nanostructures with tailored geometries have rapidly advanced in recent years Active 1D nanostructure photodetector elements can be configured either as resistors whose conductions are altered by a charge-transfer process or as field-effect transistors (FET) whose properties can be controlled by applying appropriate potentials onto the gates Functionalizing the structure surfaces offers another avenue for expanding the sensor capabilities This article provides a comprehensive review on the state-of-the-art research activities in the photodetector field It mainly focuses on the metal oxide 1D nanostructures such as ZnO, SnO(2), Cu(2)O, Ga(2)O(3), Fe(2)O(3), In(2)O(3), CdO, CeO(2), and their photoresponses The review begins with a survey of quasi 1D metal-oxide semiconductor nanostructures and the photodetector principle, then shows the recent progresses on several kinds of important metal-oxide nanostructures and their photoresponses and briefly presents some additional prospective metal-oxide 1D nanomaterials Finally, the review is concluded with some perspectives and outlook on the future developments in this area

A comprehensive review of one-dimensional metal-oxide nanostructure photodetectors

A biosensor is an integrated receptor-transducer device, which can convert a biological response into an electrical signal The design and development of biosensors have taken a center stage for researchers or scientists in the recent decade owing to the wide range of biosensor applications, such as health care and disease diagnosis, environmental monitoring, water and food quality monitoring, and drug delivery The main challenges involved in the biosensor progress are (i) the efficient capturing of biorecognition signals and the transformation of these signals into electrochemical, electrical, optical, gravimetric, or acoustic signals (transduction process), (ii) enhancing transducer performance ie, increasing sensitivity, shorter response time, reproducibility, and low detection limits even to detect individual molecules, and (iii) miniaturization of the biosensing devices using micro-and nano-fabrication technologies Those challenges can be met through the integration of sensing technology with nanomaterials, which range from zero- to three-dimensional, possessing a high surface-to-volume ratio, good conductivities, shock-bearing abilities, and color tunability Nanomaterials (NMs) employed in the fabrication and nanobiosensors include nanoparticles (NPs) (high stability and high carrier capacity), nanowires (NWs) and nanorods (NRs) (capable of high detection sensitivity), carbon nanotubes (CNTs) (large surface area, high electrical and thermal conductivity), and quantum dots (QDs) (color tunability) Furthermore, these nanomaterials can themselves act as transduction elements This review summarizes the evolution of biosensors, the types of biosensors based on their receptors, transducers, and modern approaches employed in biosensors using nanomaterials such as NPs (eg, noble metal NPs and metal oxide NPs), NWs, NRs, CNTs, QDs, and dendrimers and their recent advancement in biosensing technology with the expansion of nanotechnology

A Review on Biosensors and Recent Development of Nanostructured Materials-Enabled Biosensors.

Tellurite glass systems in the form of [ZnO]x [(TeO2)0.7-(PbO)0.3]1-x with x = 0.15, 0.17, 0.20, 0.22 and 0.25 mol% were prepared using the melt quenching technique. XRD of the prepared samples have been measured for all samples. Both FTIR (280–4000 cm−1) and UV-Vis (200–800 nm) spectra have been measured. Optical band gap and refractive index were calculated for every glass sample. Density of glass, molar volume and oxygen packing density (OPD) were obtained. Values of the direct, indirect band gap ranged were found in the range 3.41–3.94 eV and 2.40–2.63 eV with increasing of ZnO concentration. Refractive index 2.58 and dielectric constant 6.66 were heigh at 17 ZnO mol% concentration. Molar polarizability, metallization criterion, polaron radius have been calculated for every glass composition.

Optical properties of zinc lead tellurite glasses

This research work has proposed preparation of Zeolite/Zinc Oxide Nanocomposite (Zeolite/ZnO NCs) by using a co-precipitation method. Then, the prepared Nanocomposite has been tested for adsorption of Lead Pb (II) and Arsenic As (V) from aqueous solution under the room pressure and temperature. After that, the prepared adsorbent has been studied by several techniques. For adsorption process; the effect of the adsorbent masses, contact time, PH and initial metals concentration as well as, the kinetics and isotherm for adsorption process have been investigated. The results revealed that; ZnO nanoparticles (NPs) with average diameter 4.5 nm have successfully been loaded into Zeolite. The optimum parameters for the removal of the toxic metals 93% and 89% of Pb (II) and As (V), respectively, in 100 mg/L aqua solutions were pH4, 0.15 g and 30 min. According to the obtained results; pseudo second-order kinetic and Langmuir isotherm model have higher correlation coefficients and provided a better agreement with the experimental data. The prepared sorbent showed an economical and effective way to remove the heavy toxic metals due to its ambient operation conditions, low- consumption energy and facile regeneration method.

https://cyberleninka.org/article/n/1480112.pdf

Preparation of Zeolite/Zinc Oxide Nanocomposites for toxic metals removal from water

A series of zinc borotellurite glass containing erbium nanoparticles with composition of {[(TeO2)0.70(B2O3)0.30]0.7(ZnO)0.3}1−y(Er2O3)y, y = 0.005, 0.01, 0.02, 0.03, 0.04, 0.05 mole fraction were prepared by using conventional melt-quenching method. The optical properties of the prepared glass samples were measured by using high precision Elipsometer and UV-Vis spectrophotometer. The theoretical analysis for electronic polarizability, oxide ion polarizability and optical basicity were determined by using Lorentz–Lorenz equation on the basis of refractive index and optical band gap energy. It is observed that there is a linear increasing trend of electronic polarizability with increasing content of erbium nanoparticles. The oxide ion polarizability increases with refractive index and decreases with band gap energy. The optical basicity analysis shows that the glass samples possess high basicity.

/pdf/electronic-polarizability-of-zinc-borotellurite-glass-system-smila71kwq.pdf

Electronic polarizability of zinc borotellurite glass system containing erbium nanoparticles

Erbium nanoparticles (NPs) doped zinc borotellurite glasses have been prepared by conventional melt-quenching technique with the chemical composition {[(TeO2)0.70(B2O3)0.30]1-x(ZnO)x}1-y(Er3O2)y (where y = 0.005, 0.01, 0.02, 0.03, 0.04, 0.05). The structural properties of the prepared glasses were determined via X-ray diffraction (XRD) analysis and FTIR analysis. It was confirmed that the prepared glasses are amorphous. Thebonding parameters of the glasseswere analyzed by using FTIR analysis and were confirmed to be ionic in nature. The refractive index increases as the content of erbium NPs increases. The optical absorption spectra revealed that fundamental absorption edge shifts to longer wavelength as the content of erbium NPs increases. The value of band gap had been calculated and shown to be decreased with an increase content of erbium NPs. The Urbach energy was shown to be linearly increased with an increase content of erbium NPs oxides.

/pdf/effect-of-erbium-nanoparticles-on-optical-properties-of-zinc-110vmq3vbh.pdf

Effect of erbium nanoparticles on optical properties of zinc borotellurite glass system

In this paper, thermal treatment procedures were utilised to prepare crystalline nickel oxide semiconductor nanoparticles, derived from an aqueous solution. The solution consists of three compounds, primarily nickel nitrate, polyvinyl pyrrolidine and deionised H 2 O acting as metal precursor, capping agent and solvent, respectively. The solution was made prior to the drying, grinding and calcination at varying temperature settings up to 800 °C. The scanning Electron Microscopy (SEM) images allowed a detailed study on the morphological of the monocrystalline grains which were obviously observed in the specimen, showing them to be almost identical in shape and size. The Infrared Fourier Transform (FTIR) and X-ray diffraction (XRD) results demonstrated a transformation of the amorphous structure at room temperature to the crystalline structure at higher temperatures during calcination process. The mean particle diameter and particle distribution were found to be directly proportional to temperature increased. The transmission electron microscopic (TEM) analysis revealed that the particle diameters vary between 15 and 35 nm when temperature increased between 500 and 800 °C. The composition of the specimens was delineated by energy dispersed X-ray spectroscopy (EDX), which identified nickel and oxygen atomic percentages in the final products. Optical characteristics were deducted from a UV–Vis reflectance spectrophotometer, which demonstrated the energy band gap decrement as the calcination temperatures increased. Magnetic properties were determined through electron spin resonance spectroscopy (ESR), which revealed the presence of unpaired electrons. The magnetic field resonance decreases along with an increase of the g-factor value as the calcination temperature increased from 500 to 800 °C.

Halimah Mohamed Kamari

Papers

Optical properties of zinc lead tellurite glasses

Preparation of Zeolite/Zinc Oxide Nanocomposites for toxic metals removal from water

Electronic polarizability of zinc borotellurite glass system containing erbium nanoparticles

Effect of erbium nanoparticles on optical properties of zinc borotellurite glass system

Fabrication and characterization of semiconductor nickel oxide (NiO) nanoparticles manufactured using a facile thermal treatment