Synthesizing silver nanoparticles (AgNPs) from extracts of various plant parts

and of agricultural waste is strongly affected by pH. These green synthesis

methods cconsidered simple, cost effective, ecofriendly, and biologically

effective. This brief review aimed to survey the role of pH in the green

synthesis of AgNPs using those media, with a focus on its effect on AgNPs

morphology and size. This review article revealed that the alkaline pH (9 -

10) is the optimum condition for synthesizing more stable and tiny uniform

AgNPs. In addition, according to the reviewed articles, the spherical shape is

the most dominant shape of these articles in the basic medium and the size of

these particles decreases at elevated pH values and ranged from 5-40 nm

The unique characteristics of the laser beam compared to the normal light i.e. its directionality, monochromatcity, and brightness make it a very important tool in the surface engineering. The concentrated heat in the laser beam can precisely directed toward the processed region on the surface. The laser beam power, size, and scanning velocity are easily controlled during the different processing methods. Laser surface modifications of metallic materials, such as laser surface melting, laser surface alloying, and laser cladding are some of the most important methods to improve the mechanical properties of the processed layer on the surface. A pulsed Nd-YAG laser surface melted specimens of low carbon steel with a maximum power of 90W at different processing parameters. The rapid melt and resolidification of the treated layer produced a refinement in the microstructure. The original microstructure of this steel (Ferrite + Pearlite) has been transformed to new phases of martensitic and bainitic structures. The melted layer consists of the melted pool, the heat affected zone, and the substrate. The maximum hardness of the laser melted layer is more than 400 HV.

Key words:Laser surface Melting, Carbon steel, Microstructure, Microhardness

الملخص

Acute conjunctivitis is described as inflammation of the conjunctiva that lasts less than 3 to 4 weeks, showing cellular infiltration and exudation. Conjunctivitis can cause significant and lasting harm to the eye, resulting in severe inflammation in the corneal lid. This study seeks to isolate and identify the particular bacterial pathogens responsible for conjunctivitis in patients at Tripoli Eye Hospital. Collection of bacterial samples from patients with conjunctivitis was conducted at the ophthalmic consultative clinic within Tripoli Eye Hospital, Libya between September 2021 and January 2022. Tests were done to separate bacterial pathogens causing conjunctivitis and to test their resistance to antibiotics. Among 140 samples, bacterial infection was detected in 86% of cases while 14% yielded negative results. Males had a higher prevalence of bacterial infections at 63% in comparison to females. Both male and female individuals aged 60-79 years had the highest percentage of bacterial conjunctivitis cases at 51%. Segregation tests showed that the majority (82%) were Gram-positive, while a minority (18%) were Gram-negative, with Staphylococcus aureus being the most prevalent bacteria (35%), closely followed by Staphylococcus epidermidis (32%). Streptococcal pneumoniae and Enterobacter spp had rates of 2% which were lower. The majority of organisms showed sensitivity to levofloxacin (43%), while there was only a small amount of resistance to polymyxin B (4%). Professional attention and microbiological research are crucial for verifying clinical diagnoses and carrying out suitable and efficient treatments.

Since the Alhamada area is known for its rangelands and most of its inhabitants raise animals, especially sheep and goats, this study was conducted by collecting samples randomly from six herds of sheep distributed randomly from the specific areas of Qurayat and Ghadames This study was aimed to determine the prevalance of Eimeria, which causes coccidian in sheep's and study the effects of many factors such as age, sex, and the breeding system, it is the first study conducted in the Hamada area on this parasite, using microscopic examination, 54 samples of sheep and goat feces were examined, of different ages and of both sexes in the month of May 2022. The result showed that the infection rate was 28% in sheep and 43% in goats. It was noted that there were no significant differences for age in the infection rate, as the highest infection rate was in the age group (>2) years (39%), while the lowest infection rate was in the age group of (1-2) years (7%), it was also shown that there is no significant difference for gender on the infection rate, as the infection rate in males was (22%) and females (48%). The results showed a slight difference in the infection rate between the open and closed breeding systems in the Hamada region, with the closed system averaging 25% compared to 20% in the open system. Clinical signs also appeared on some of the infected animals, including diarrhea, general weakness, and some of them showed plucking of wool/hair.