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This paper reviews technologies used for the prevention of electromagnetic interference in current portable electronic products. It studies the need for future advanced products and some of the technologies likely to be available. The focus is on housing technologies and the products available for giving greatest electromagnetic compatibility with the latest European and other emission and susceptibility standards. It is concluded that new or improved approaches which are better able to ensure long‐term reliability will be essential for the 100 MHz clock speed equipment likely to be in production within the coming five years.

For some years now the dominant techniques for coating thickness have been based on electronic instrumentation. As such they have been subject to the same rigid progress which has been seen in the electronics industry. Components have become smaller and more complex and the microprocessor is pushing into more and more areas of control and measurement. Development of the various techniques has increased the range of coating‐substrate combinations that are measurable and improvements to stability have extended the measurement range. Statistical evaluation of results has been added to all but the simplest instruments. Describes the principal instrument types and in conclusion sees their intelligent use and the implementation of statistical process control as making the life of the organic finisher easier and more profitable.

The aim of this paper is to analyse the recent changes in the role played by Africa as a traditional natural resources supplier for the world economy in a multipolar context. We highlight, on the one hand, how Africa remains a prominent supplier of critical minerals needed for information and communication technologies (ICT), including platinum, vanadium, coltan, chromium, manganese, zirconium, etc., and how the boomerang effect results in Africa also importing electronic waste. On the other hand, we show how the BRICS’ growth model, based on a very intensive use of natural resources acquired through international trade, is now being fuelled by Africa too. BRICS countries (especially China and India) are making foreign direct investments in Africa using their state companies to ensure the supply of natural resources under favourable economic terms. Thus, Africa appears as a disputed territory between the old domination of the advanced capitalist countries and emerging powers like the BRICS. However, this should not mask the fact that the European Union and North America are still the dominant foreign powers in the continent. Finally, we discuss which scenarios are open to further this multipolar moment, particularly in the wake of the great crisis.

THE METHODS available for the application of chromium coatings are listed in Table 2. Until recently most chromium coatings have been applied either by electrodeposition or chemical vapour deposition. Vacuum and powder‐coating techniques are breaking through in strip‐coating, and electrodeposition has also been investigated extensively since steel, having a thin ‘flash‐coating’ of chromium, can compete successfully with tin‐plate.

This paper aims to investigate the parametric study of addition of snail shell particles (SSp) and bath temperature on the properties of Zn-ZnO-SSp composites coating.

Bath temperatures of 60°C and 90°C and SSp of 0, 5, 10, 15, 20 and 25g were used in the electrodeposition. The microstructure, electrochemical, wear and hardness values of the coated samples were determined.

Highest coating thickness of 240 µm, 277 per cent improvement in hardness values, 66.67 per cent improvement of wear rate were obtained at bath temperature of 60oC and 15gSSp addition over that of the uncoated sample. There was improvement in corrosion resistance after composites coating. Maximum improvement in the properties was obtained at bath temperature of 60°C at 15gSSp addition.

It has been established in this work that bath treatment and SSps improved the properties of the developed coating.

The purpose of this paper is to investigate the effect of Mg²⁺substitution on the magnetic and electrical properties of Li_0.35−x Mg_2x Zn_0.3 Fe_2.35−xO₄ thick films synthesized with polyvinyl alcohol (PVA) matrix.

The nanoferrites Li_0.35−x Mg_2x Zn_0.3 Fe_2.35−xO₄ (x=0, 0.07, 0.14, 0.21, 0.28 and 0.35) were synthesized by chemical technique using aqueous solution of PVA (the matrix) and thick films were fabricated by screen printing technique. The DC magnetic hysteresis measurements, AC magnetic susceptibility and DC electrical resistivity were measured as a function of temperature.

The lattice parameter of thick film Li_0.35−x Mg_2x Zn_0.3 Fe_2.35−xO₄ (x=0, 0.07, 0.14, 0.21, 0.28 and 0.35) increases with the substitution of Mg²⁺ions for Li¹⁺and Fe³⁺. The surface morphology of the thick films showed the grain size increasing with Mg²⁺substitution till x=0.21 and then decreasing for the higher concentrations of magnesium. The magnetic moment n_B (μ_B) computed from the M_s obtained by extrapolation of the magnetization curve showed a gradual decrease with the composition till x=0.21, beyond which a sudden decrease was observed. The resistivity of the films at room temperature had variation with composition x, similar to that of magnetic moment. The activation energies ΔE_F and ΔE_P were found to vary with composition x of the ferrite system.

The paper reports, for the first time, the magnetic and electrical properties of fritless Li_0.35−xMg_2xZn_0.3Fe_2.35−xO₄ thick films using PVA polymer matrix. Up to x=0.21 (Mg²⁺), grain size increases and Curie temperature decreases beyond which reverse effect takes place.

In this paper, a computational model of a coaxial magnetic gear (MG) design with viscose ferrofluid between rotors is proposed. Viscose ferrofluid is used to decrease the magnetic reluctance and therefore creates higher magnetic torque. However, viscose friction of ferrofluid is undesirable and must be minimised in this particular application. MG is supposed to operate under low rotational speeds, where the dynamic viscose friction is very low, and the effects of the viscose ferrofluid over the MG’s efficiency must be estimated. The paper aims to analyze the performance of MG with viscose ferrofluid and to estimate the MG efficiency by computational model using finite element method (FEM).

An MG design with viscose ferrofluid between the outer low-speed rotor and modulating steel segments was modelled as a coupled transient magnetic field problem and a kinematic model with viscous friction coefficients derived from a previously computed fluid dynamics model.

The proposed computational implementation is suitable for homogeneous magnetic fluid modelling in electromagnetic actuators and rotational machines. The results regarding power and torque transmission of MG were obtained by coupled finite element modelling. The efficiency of MG significantly decreased due to ferrofluid friction.

The described MG design with viscose ferrofluid is a novel device with new operational characteristics, and new results for the effects of viscose ferrofluid friction in the outer magnetic field over the MG efficiency are estimated.

The most reliable, inexpensive, and trouble‐free shielding method known at the present is spray coating using paints containing conductive metal particles. The best metals are those which do not lose conductivity due to oxidation. These consist of gold, platinum, palladium, iridium, silver and osmium. The least expensive is silver. A coating containing fine silver particles is an excellent conductor and shield. Paints containing fine silver particles have been available a long time but are very happy and very expensive. Their performance is, however, excellent.

In the developing field of nano-materials synthesis, copper oxide nanoparticles (NPs) are deemed to be one of the most significant transition metal oxides because of their intriguing characteristics. Its synthesis employing green chemistry principles has become a key source for next-generation antibiotics attributed to its features such as environmental friendliness, ease of use and affordability. Because they are more environmentally benign, plants have been employed to create metallic NPs. These plant extracts serve as capping, stabilising or hydrolytic agents and enable a regulated synthesis as well.

Organic chemical solvents are harmful and entail intense conditions during nanoparticle synthesis. The copper oxide NPs (CuO-NPs) synthesised by employing the green chemistry principle showed potential antitumor properties. Green synthesised CuO-NPs are regarded to be a strong contender for applications in the pharmacological, biomedical and environmental fields.

The aim of this study is to evaluate the anticancer potential of CuO-NPs plant extracts to isolate and characterise the active anticancer principles as well as to yield more effective, affordable, and safer cancer therapies.

This review article highlights the copper oxide nanoparticle's biomedical applications such as anticancer, antimicrobial, dental and drug delivery properties, future research perspectives and direction are also discussed.