Analysing The Effect Of Metal Complexes With Cefuroxime On Some Selected Bacteria

Silver and its compounds have long been utilized as antimicrobial agents in medicine. Silver sulfadiazine, a broad-spectrum antibiotic ointment, is widely used and effective against a wide range of bacteria and some yeast. Copper and its alloys possess natural antimicrobial properties. Ancient civilizations recognized and utilized the antimicrobial effects of copper long before the understanding of microbes in the nineteenth century. Mechanochemistry refers to reactions induced by the input of mechanical energy, typically involving solids, such as grinding in ball mills. It is gaining increased attention due to its ability to promote rapid and quantitative reactions between solids, often without the need for additional solvents. Historically, mechanochemistry has been a secondary approach to chemical synthesis, with solution-based methods being the default choice. Building upon our previous research on antibiotic resistance, this paper presents the impact of mechanochemically synthesized copper (II) and silver (I) complexes with cefuroxime on cephalosporin-resistant bacteri

Facile Synthesis of Hafnium Oxide Nanoparticle Decorated on Graphene Nanosheet and Its Photocatalytic Degradation of Organic Pollutants under UV-Light Irradiation

The HfO2 nanoparticles and the nanocomposites of HfO2-graphene (10, 30, and 50 wt%) were prepared via precipitation and simple mixing method. The XRD pattern confirmed the presence of monoclinic HfO2 and hexagonal graphene in the nanocomposite. Raman spectroscopy studies revealed the formation of HfO2-graphene nanocomposite. According to SEM and TEM images the HfO2, NPs are spherical, and their size is less than 10 nm, anchored on the surface of the graphene sheets. The EDX spectrum shows carbon, oxygen, and HfO2 and reveals the formation of the HfO2-graphene nanocomposite. The UV-vis absorption spectra show the optical properties of synthesized HfO2-graphene nanocomposite. The study examines the influence of different ratios of the addition of graphene on the photocatalytic activity of HfO2-graphene. It was found that the HfO2-graphene (50 wt%) 40 mg nanocomposite exhibits enhanced photocatalytic activity than the bare HfO2 towards the methylene blue photodegradation, an aromatic pollutant in water under UV light irradiation, which can be applied optimally for individually wastewater management system. The HfO2-graphene (50 wt%) photocatalyst degrades 81 ± 2% of tetracycline in 180 min, implying that tetracycline can be degraded more efficiently under UV light. The enhancement in photocatalytic activity under UV light illumination can be attributed to the effective separation of photogenerated electrons, inhibiting recombination in the HfO2-graphene composite

Quality-of-service analysis of scheduling algorithms in wireless networks

Recent advance in wireless communications has led to increasing demands on wireless systems. There are inherent limitations on the performance of such systems due to physical constraints such as finite bandwidth, power, interference and fading. The adverse effects of interference and fading can be mitigated by intelligent scheduling algorithms. Significant effort has been put forth by the research community in understanding the impact of scheduling algorithms on network performance. A well-celebrated milestone is the development of throughput-optimal scheduling algorithms. These are algorithms that will stabilize the system whenever it is possible to stabilize the system using any other algorithm. While stability is a useful first-order measure of success, many delay-sensitive wireless applications require stronger guarantees on the Quality-of-Service (QoS). Unfortunately, there have been few results in the literature on the QoS guarantees of scheduling algorithms. In this thesis, we are interested in QoS metrics in the form of the probability that a certain function f(Q) of the backlog vector Q exceeds a threshold B, where the function f(˙) is designed to reflect the delay requirement of the system. The question of how to design scheduling algorithms that minimize the aforementioned overflow probability turns out to be very challenging. One of the reasons is that for general queuing systems, there is no closed form solution for the distribution of queue lengths in the system. The approach that we take is to use the theory of large deviations to study the asymptotic decay-rate of the overflow probability when the threshold B becomes large. A scheduling algorithm is said to be QoS-optimal in the large-deviations sense when it maximizes this large deviations decay-rate. The main contributions of this dissertation are the following. For a general network topology with multi-hop transmission of multiple flows subject to general interference constraints, we provide a sufficient condition to determine when a scheduling algorithm is QoS-optimal. We study several commonly used multi-hop wireless systems such as convergecast to the root in a tree topology and end-to-end data transfer in a system with acyclic multihop flows, and use the aforementioned condition to provide insights into the behavior of the optimal scheduling algorithm. We then successfully turned the insights into novel practical scheduling algorithms and proved their optimality both in theory and via simulations

Biowaste-Derived Interconnected Carbon Nanosheet-Supported Iron as a Highly Stable and Excellent Electrocatalyst for Overall Water Splitting

Water splitting needs low-cost materials that can efficiently catalyze both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). We prepared biowaste-derived self-nitrogen-doped interconnected hierarchically porous carbon nanosheet Fe@PSAC as a bifunctional and ultradurable electrocatalyst for water splitting. Fe@PSAC exhibits a low overpotential of 118 mV (84 mV/dec) for HER and 231 mV (66 mV/dec) for OER @ 10 mA/cm2 in 1.0 M KOH (without iR correction). Fe@PSAC exhibits durability for 100 h with minimum potential losses of 2.9 and 2.3% for HER and OER, respectively. The turnover frequency of Fe@PSAC (0.2297/s) and IrO2 (0.0231/s) for OER and Fe@PSAC (0.0784/s) and Pt/C (0.1806/s) for HER was nearer to Pt/C and greater than IrO2, respectively. The synergy between self-nitrogen-doped interconnected hierarchically porous carbon nanosheets and iron endows excellent bifunctional activity and stability. The Fe@PSAC//Fe@PSAC water electrolyzer exhibits excellent activity at 1.58 V to reach 10 mA/cm2 with high stability for 120 h with a 3.2% potential loss. The Fe@PSAC//Fe@PSAC electrocatalyst shows an exceptional activity of 1.58 V using solar-assisted water electrolysis. The Fe@PSAC//Fe@PSAC electrode has been strongly recommended for low-cost hydrogen fuel production on a large scale

Biowaste-Derived Interconnected Carbon Nanosheet-Supported Iron as a Highly Stable and Excellent Electrocatalyst for Overall Water Splitting

Water splitting needs low-cost materials that can efficiently catalyze both oxygen evolution reaction (OER) and hydrogen evolution reaction (HER). We prepared biowaste-derived self-nitrogen-doped interconnected hierarchically porous carbon nanosheet Fe@PSAC as a bifunctional and ultradurable electrocatalyst for water splitting. Fe@PSAC exhibits a low overpotential of 118 mV (84 mV/dec) for HER and 231 mV (66 mV/dec) for OER @ 10 mA/cm2 in 1.0 M KOH (without iR correction). Fe@PSAC exhibits durability for 100 h with minimum potential losses of 2.9 and 2.3% for HER and OER, respectively. The turnover frequency of Fe@PSAC (0.2297/s) and IrO2 (0.0231/s) for OER and Fe@PSAC (0.0784/s) and Pt/C (0.1806/s) for HER was nearer to Pt/C and greater than IrO2, respectively. The synergy between self-nitrogen-doped interconnected hierarchically porous carbon nanosheets and iron endows excellent bifunctional activity and stability. The Fe@PSAC//Fe@PSAC water electrolyzer exhibits excellent activity at 1.58 V to reach 10 mA/cm2 with high stability for 120 h with a 3.2% potential loss. The Fe@PSAC//Fe@PSAC electrocatalyst shows an exceptional activity of 1.58 V using solar-assisted water electrolysis. The Fe@PSAC//Fe@PSAC electrode has been strongly recommended for low-cost hydrogen fuel production on a large scale

Facile Synthesis of Hafnium Oxide Nanoparticle Decorated on Graphene Nanosheet and Its Photocatalytic Degradation of Organic Pollutants under UV-Light Irradiation

The HfO2 nanoparticles and the nanocomposites of HfO2-graphene (10, 30, and 50 wt%) were prepared via precipitation and simple mixing method. The XRD pattern confirmed the presence of monoclinic HfO2 and hexagonal graphene in the nanocomposite. Raman spectroscopy studies revealed the formation of HfO2-graphene nanocomposite. According to SEM and TEM images the HfO2, NPs are spherical, and their size is less than 10 nm, anchored on the surface of the graphene sheets. The EDX spectrum shows carbon, oxygen, and HfO2 and reveals the formation of the HfO2-graphene nanocomposite. The UV-vis absorption spectra show the optical properties of synthesized HfO2-graphene nanocomposite. The study examines the influence of different ratios of the addition of graphene on the photocatalytic activity of HfO2-graphene. It was found that the HfO2-graphene (50 wt%) 40 mg nanocomposite exhibits enhanced photocatalytic activity than the bare HfO2 towards the methylene blue photodegradation, an aromatic pollutant in water under UV light irradiation, which can be applied optimally for individually wastewater management system. The HfO2-graphene (50 wt%) photocatalyst degrades 81 ± 2% of tetracycline in 180 min, implying that tetracycline can be degraded more efficiently under UV light. The enhancement in photocatalytic activity under UV light illumination can be attributed to the effective separation of photogenerated electrons, inhibiting recombination in the HfO2-graphene composite

Antibacterial Activity and Anticorrosive Efficiency of Aqueous Methanolic Extract of Artemisia pallens (Asteraceae) and its major Constituent

An aqueous-methanolic [methanol:water (1:1)1 extract of the whole plant of Artemisia pallens (Family: Asteraceae) has shown good antibacterial activity against Pseudomonas aeruginosa and Shigella flexneri at the concentration of 100 mg/mL. The activity-guided fractionation has led to isolation of compound 4-hydroxyphenyl-/3-D-glucopyranoside (which is known as arbutin), as a major constituent and exhibited the same antibacterial activity at a concen-tration of 17 mg/mL. Both the crude extract and arbutin also showed 94% anticorrosive efficiency against mild steel in 1M HC1 at concentration of 200 mg/L