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Co1–xZnxFe2O4 (x = 0.0, 0.2, 0.4, 0.6, 0.8) cobalt zinc nanoferrites (CZF) nanoparticles were created in this study utilizing the auto-ignition procedure with citric acid as an oxidizing agent. Following thermogravimetric–differential thermal analysis, the prepared Co1–xZnxFe2O4 powder was sintered at 1000°C for 4 h. The single-phase cubic structure of Co-Zn ferrite nanoparticles was described by X-ray diffraction studies, and its outcomes show particle size fluctuation. Fourier transform infrared spectra show that phase formation occurred. Due to the ferrite samples, scanning electron microscope images demonstrate the aggregation of spherical grains. Peaks of the corresponding components Co, Zn, Fe and O were seen in the energy dispersive X-ray spectra, indicating the production of cobalt zinc ferrite. By employing a vibrating sample magnetometer to evaluate the magnetic characteristics of the ferrite output, soft ferrite material was found to be present. The range 58.55–74.46 nm is discovered to be the average crystallite size of the ferrite nanoparticles produced by field emission-scanning electron microscope. Transmission electron microscopy elaborates clustering of grains. With increase in Zn content in cobalt zinc ferrite nanoparticles, hysteresis loops were shown to be modified for magnetic characteristics, which include Ms, Mr, Hc and Mr/Ms. CZF nanoferrites can be employed in microwave devices because of their dielectric properties, i.e., the tangent loss is lower at high frequencies. Co0.2Zn0.8Fe2O4 exhibits surprisingly high dielectric permittivity with small dielectric loss and can be exploited for power storage at high frequencies. These results indicate CZF as a promising nanomaterial with unique technological applications. [ABSTRACT FROM AUTHOR]

The increasing emergence of bacterial resistance is a challenge for the research community, thus novel antibacterial agents should be developed. Metal nanoparticles are promising antibacterial agents and could solve the problem of antibiotic resistance. Herein, we used Gardenia thailandica methanol extract (GTME) to biogenically synthesise zinc oxide nanoparticles (ZnO-NPs). The characterisation of ZnO-NPs was performed by UV spectroscopy, FTIR, scanning and transmission electron microscopes, dynamic light scattering, and X-ray diffraction. The antibacterial activity of ZnO-NPs was studied both in vitro and in vivo against Pseudomonas aeruginosa clinical isolates. Its minimum inhibitory concentration values ranged from 2 to 64 µg/mL, and it significantly decreased the membrane integrity and resulted in a significant increase in the inner and outer membrane permeability. Also, the ZnO-NPs treated cells possessed a distorted and deformed shape when examined by scanning electron microscope. The in vivo study (biochemical parameters and histological investigation) was conducted and it revealed a protective effect of ZnO-NPs against the deleterious influences of P. aeruginosa bacteria on lung, liver, and kidney tissues. LC-ESI-MS/MS revealed a phytochemical tentative identification of 57 compounds for the first time. We propose that GTME is a useful source for ZnO-NPs which has a promising antibacterial activity. [ABSTRACT FROM AUTHOR]

Ikaite is a calcium carbonate hexahydrate that forms at temperatures close to the freezing point of water; thus, its occurrence is associated with cryogenic conditions. This mineral is metastable and quickly transforms to calcite at temperatures above 5 °C. Pseudomorphs of calcite after ikaite are known as glendonite. The nanostructure of 25 000–43 000 year old glendonite from Victoria cave (Southern Ural, Russia) was investigated in search of structural features indicative of the ikaite-to-calcite transformation. Scanning electron microscope images display several micrometer- to submicrometer-size pores and indicate high intergranular porosity among the loosely aggregated grains. Transmission electron microscopy (TEM) data show evidence of 10–20 nm nanotwins [twin law (101̅4)] and 10–40 nm overlapping nanograins. Scanning TEM images reveal that the individual grains contain 5–10 nm long and 2–4 nm wide mesopores (sizes between 2 and 50 nm), which are aligned parallel to [1010] of calcite and might be associated with a crystallographically oriented dehydration of the precursor ikaite. Fourier transform infrared spectroscopy reveals no evidence of structural water but absorption bands related to molecular water trapped in fluid inclusions are present. Nitrogen absorption/desorption measurements show that the specific surface area of 5.78 m2/g and the pore volume of ~0.07 cm3/g for calcite, the constituent of glendonite, are comparable to those of a common natural calcite. We suggest that the aligned mesopores, frequently occurring twins, small grain size, presence of aqueous inclusions and the high micrometer- to submicrometer-size intergranular porosity arise from the ikaite-to-calcite transformation and thus may be used as criteria for the former presence of ikaite and hence for cold paleotemperatures. However, since similar features might also be common in biogenic carbonates, the diagnostic macroscopic pseudomorphs after ikaite are equally important for identifying glendonites and inferring cryogenic conditions. [ABSTRACT FROM AUTHOR]

Since its invention, electron microscope (EM) has been a valuable tool in the development of scientific theory and it contributed greatly to biology, medicine and material sciences. This wide spread use of EMs is based on the fact that they permit the observation and characterization of materials on a nanometer (nm) to micrometer (µm) scale. In this review article, the transmission electron microscope (TEM) and the scanning electron microscope (SEM) were defined and reviewed. The EMs functions and types were discussed, in addition to clarifying the parts and components of TEM, SEM and optical microscopes for neophyte, starting from the sample's preparation through imaging of the samples. Also, this review will point out the limitations and advantages of each type and issues to be considered during experimental design. Advanced EM techniques are listed as well.in this review, Diagrammatically, identify the various parts of a microscopes, what is the differences between TEM, SEM and optical microscopes and finally the methods of samples preparation have been mentioned. [ABSTRACT FROM AUTHOR]

Composite materials are materials that are made of two or more materials that remain separate and differ on a macroscopic level while forming a single component so as to produce a composite material that has different mechanical properties and characteristics from the material it forms. Particle composite materials consist of particles held together by a matrix. In this study, an epoxy resin matrix was used with Polymesoda erosa clam shell nanopowder filler. Nano-sized fillers have many advantages over macro-sized ones. The nano-sized particles will have a high surface area, thereby increasing the mechanical strength of the material. The powdered nanoparticles produced will be analyzed using Fourier Transform Infrared (FTIR), Transmission Electron Microscope (TEM), and Scanning Electron Microscope (SEM). Based on the results of SEM and TEM, the nanopowder of clamshell has a size below 100 nm. The FTIR results of the powdered shellfish showed the presence of carbonate bonds C-O, C=O, and Ca-O. [ABSTRACT FROM AUTHOR]

Dry sliding wear tests and corresponding particulate matter (PM) analysis were conducted on a newly developed SiC-graphite-based composite friction material, paired with two types of HVOF counterface/discs: WC-CoCr and WC-FeCrAlY coatings, with a conventional martensitic stainless steel counterface as a reference. The trials were conducted on a pin-on-disc testing equipment at room temperature and a constant sliding velocity and contact pressure of 7 m/s and 0.5 MPa, respectively. The coefficient of friction (CoF) curves with the uncoated disc exhibited considerable fluctuations. On the other hand, the coated discs featured an increase in the CoF at the beginning of the tests, followed by either a continuous reduction until the end of the testing duration or the attainment of a steady state regime. The pin wear and emissions with both coatings were appreciably lower when compared to the trials with the uncoated disc. The evaluation of the friction layer observed a significant contribution of the counterface for all the pairings. The PM analysis was conducted on the particles that were lying in the range of 10 μm and 2.5 μm on a scanning electron microscope (SEM), and particles from 2.5 μm and 1 μm on transmission electron microscope (TEM), with an emphasis on the particles that were detached from the pin surface and friction layer to explain the wear mechanisms for each pairing. Through this, the need for the proper selection of both friction material and counterface to avoid the emission of harmful compounds in the environment was highlighted. [ABSTRACT FROM AUTHOR]

[Display omitted] • High-speed electrodeposition technology for efficient Cu pillar adhesion. • Current density dominated the Cu microstructure, pillar morphology and its adhesion. • Finite element analysis of high-speed electrodeposition. • Enhancement of electrolyte circulation can greatly facilitate electrodeposition. The fabrication of Cu pillars has recently attracted much attention from the microelectronic/communication industry because pillars can act as thermal dissipation devices and electrical interconnections among different packaging levels, providing efficient utilization of space in microelectronic packaging applications. This study was conducted to investigate the fabrication of Cu pillars through a high-speed electrodeposition method and their adhesion to an Ajinomoto build-up film (ABF). The morphological, crystallographic, electrical, and mechanical characteristics of the Cu pillars electroplated with various current densities (j = 2, 5, 7.5, and 10 A/dm2) were systematically investigated through a scanning electron microscope (SEM) combined with electron backscatter diffraction (EBSD) analysis system, field-emission transmission electron microscope (FE-TEM), an ohm meter, and a nanoindenter. Additionally, the adhesion of the Cu pillars to an ABF substrate after high-temperature storage was evaluated via a shear test. Finally, a finite element analysis (FEA) method (COMSOL-Multiphysics) was employed to simulate the current density and electrolyte distributions in a via structure upon high-speed Cu electrodeposition to characterize the morphological/crystallographic/mechanical transitions induced by increasing j. This valuable information advances our understanding of electrochemical metal deposition and would be helpful in the development of high-speed Cu electrodeposition technology. [ABSTRACT FROM AUTHOR]