Copper has long been known as a metal with outstanding antimicrobial properties. Although ancient healers were not familiar with the mechanisms of its influence on microorganisms, they had empirically established its effectiveness in sterilizing drinking water, disinfecting wounds, treating skin diseases, various infections and other maladies. Recently, there has been renewed interest in investigating copper and its alloys as possible materials that can limit the spread of bacteria and viruses, given that humanity is often facing various local epidemics, and rarely pandemics, as ongoing Corona virus, SARS CoV-2, first detected in March 2020. This paper reviews the recent literature in the research field of antimicrobial properties of metallic copper, its alloys and other copper - based materials, with the aim to promote their future implementation on contact surfaces, primarily in hospitals and institutions with a high frequency of people where the probability of spreading infection is increased.
Lead-free solders have become a main focus of the electronic industry in recent years, because of the high toxicity of lead. Alloys based on the Sn-Bi system figure as potential replacements for Sn-Pb alloys in soldering due to favorable properties and low cost. One of the main advantages of these alloys are low melting temperatures, while additional advantages include good compatibility with substrates, low process temperature, high reliability, and potential applications in conjunction with reduced graphene oxide nanosheets as thermal interface materials. In this paper, characterization of microstructural and thermal properties as well as hardness measurements of seven alloys of different Sn-Bi compositions are performed. Structural properties of the samples were analyzed using optical microscopy and scanning electron microscopy and energy dispersive X-ray spectroscopy (SEM-EDS). Thermal conductivity of the samples was investigated using the xenon-flash method, and phase transition temperatures were measured using the differential scanning calorimetry (DSC) analysis.
An optical sensor IC in 0.35-<inline-formula> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> CMOS is presented containing a single-photon avalanche diode (SPAD) and a fast quadruple-voltage quenching circuit (QVQC). The QVQC features a fast active quenching time of 0.93 ns, a total quenching time of 1.9 ns, and an adjustable total dead time (8.6–200 ns) to reduce the afterpulsing probability (APP). To verify the quenching performance, the circuit was integrated with a 40-<inline-formula> <tex-math notation="LaTeX">$\mu \text{m}$ </tex-math></inline-formula> diameter SPAD. Experiments show the reduction of afterpulsing by a low detection threshold and by fast quenching with a slew rate of 13.8 GV/s. Thus, an APP of 3.2% at 27-ns dead time, a peak photon detection probability (PDP) of 67.6% at 652 nm, and a PDP of 34.7% at 854 nm were measured at 13.2-V excess bias.
An algorithmic instrumentation amplifier (INA) with dynamic analog signal processing (DASP) is presented in this article. The proposed approach is based on any basic INA (BINA) subjected to a simple algorithmic operation performed by DASP. The resulting common-mode rejection ratio (CMRR) equals double squared CMRR value of the BINA, with no need for any additional matching. The prototype has been made in a discrete technique with a single supply voltage of 2.7 V. The voltage-mode INA(VMIA) with two operational amplifiers (OAs) has been used as the BINA. The measurements have been performed for six different clock pulse frequencies ranging from 30 to 80 kHz with a step of 10 kHz used in the DASP. The resulting CMRR of 90.03, 80.35, 66.48, and 53.15 dB are achieved starting from a poor CMRR of 42.52, 36.80, 30.09, and 23.76 dB of the BINA, respectively, confirming the proposed CMRR enhancement model $2\times $ CMRR [dB] +6 dB.
The highest quality silage is produced from corn (corn silage), which is also the most common livestock feed. The lack of corn silage in livestock production can be compensated only by concentrated feed, which is usually more expensive, but this is a wellapplied practice in B&H. Therefore, the main aim of this paper was to determine the economic viability of corn silage production in B&H for the period 2014-2019. Primary data for this research were collected based on a semi-structured interview with representatives of the farm "Farma Spreča" Kalesija with a total harvested area of 500 ha. Results indicate that with total harvested area increases 61.29 %, yield increases only 6.26 %, while efficiency decreased by 6.38 % implying problems related to productivity. Based on that, corn silage production in B&H shows positive financial performances, but low yield even with a strong increase in harvested areas indicates the need for further technological and technical improvement.
Extract of Alchemilla vulgaris L. was investigated as eco-friendly corrosion inhibitor for aluminium in 3 % NaCl using electrochemical techniques. According to the results, inhibition efficiency increases with the increase concentration of extract and the highest efficiency (~80 %) is recorded for the maximal concentration of extract (1.0 g L–1). The inhibition activity of extract occurs by the spontaneous physisorption (ΔG ≈ –16 kJ mol–1) on active sites of aluminium surface that follows Freundlich isotherm. Polarization curves showed that Alchemilla vulgaris L. extract act s a mixed-type inhibitor. The effect of temperature on the aluminium corrosion and inhibition action of extract was studied and the result showed that the corrosion rate increased and the inhibitor efficiency decreased with increase of temperature. The calculated values of the activation energy confirmed presence of inhibitive Alchemilla vulgaris L. extract on aluminium surface.
This paper presents the first comprehensive tutorial on a promising research field located at the frontier of two well-established domains, neurosciences and wireless communications, motivated by the ongoing efforts to define the Sixth Generation of Mobile Networks (6G). In particular, this tutorial first provides a novel integrative approach that bridges the gap between these two seemingly disparate fields. Then, we present the state-of-the-art and key challenges of these two topics. In particular, we propose a novel systematization that divides the contributions into two groups, one focused on what neurosciences will offer to future wireless technologies in terms of new applications and systems architecture (Neurosciences for Wireless Networks), and the other on how wireless communication theory and next-generation wireless systems can provide new ways to study the brain (Wireless Networks for Neurosciences). For the first group, we explain concretely how current scientific understanding of the brain would enable new applications within the context of a new type of service that we dub brain-type communications and that has more stringent requirements than human- and machine-type communication. In this regard, we expose the key requirements of brain-type communication services and discuss how future wireless networks can be equipped to deal with such services. Meanwhile, for the second group, we thoroughly explore modern communication systems paradigms, including Internet of Bio-Nano Things and wireless-integrated brain–machine interfaces, in addition to highlighting how complex systems tools can help bridging the upcoming advances of wireless technologies and applications of neurosciences. Brain-controlled vehicles are then presented as our case study to demonstrate for both groups the potential created by the convergence of neurosciences and wireless communications, probably in 6G. In summary, this tutorial is expected to provide a largely missing articulation between neurosciences and wireless communications while delineating concrete ways to move forward in such an interdisciplinary endeavor.
Nema pronađenih rezultata, molimo da izmjenite uslove pretrage i pokušate ponovo!
Ova stranica koristi kolačiće da bi vam pružila najbolje iskustvo
Saznaj više