The Estimated of Boron Concentration in Water Samples of the north of Basrah Governorates Using AAS Techniques

Significant risks for human health may results from exposure to non pathogenic toxic contaminants that are often globally ubiquitous in waters from which drinking water is derived to measure the Boron, 105B concentration in water samples in Basra governorate in north of Iraq. The measurements were performed by analyzing the water samples collected from 55 location using AAS Technique. The Boron concentrations which are obtained ranged from 0.1185 ppm in Alhwair - Al-Samayd to 1.539 ppm in Hawair- Harde river in water samples. The results are presented and compared with other studies. The results could be utilized to make distinctive supplementary contributions when contam- ination event occurs and to implement water quality standards by concerned authorities to maintain radioactive contamination-free drinking water supplies for the people. The study further reveals that 55 surface water samples have boron below detection limit. The presence of boron in drinking water sources in this territory is of natural origin. Thus, there is possibility of severe pollution problem with boron in near future.nbs

Optimizing Grid Resilience: A Capacity Reserve Market for High Impact Low Probability Events

This paper addresses the challenges of high-impact low-probability (HILP) events by proposing a novel capacity reserve event market for mobile generation assets, aimed at supporting the transmission network during such incidents. Despite the usefulness of portable generators and mobile energy units in restoring power, there are drawbacks such as environmental impact, finite operation, and complex cost recovery. The proposed market integrates these resources into a dispatch framework based on pre-established contracts, ensuring fair compensation and considering factors like capacity, pricing, and travel distance. Resource owners receive advanced notifications for potential events, allowing them to adjust their bids for cost recovery. Simulations on an IEEE 30-bus case have been conducted to demonstrate the model effectiveness in increasing grid resiliency

The Quantum Emergence of Chaos

The dynamical status of isolated quantum systems, partly due to the linearity of the Schrodinger equation is unclear: Conventional measures fail to detect chaos in such systems. However, when quantum systems are subjected to observation -- as all experimental systems must be -- their dynamics is no longer linear and, in the appropriate limit(s), the evolution of expectation values, conditioned on the observations, closely approaches the behavior of classical trajectories. Here we show, by analyzing a specific example, that microscopic continuously observed quantum systems, even far from any classical limit, can have a positive Lyapunov exponent, and thus be truly chaotic.Comment: 4 pages, 4 figure

Role of oxidative stress in therapeutic administration of artesunate on sperm quality and testosterone level in male albino rats

The effects of antioxidants, vitamins C and E, on sperm quality, testosterone levels, superoxide dismutase (SOD) activity and malondialdehyde (MDA) concentration were studied in artesunate treated rats. 25 male rats (160 to 250 g) divided into five groups were used for the study. Group 1 animals received normal saline and served as control while groups 2 to 5 received artesunate in therapeutic doses of 2.9 mg/Kg body weight on day 1 and 1.45 mg/Kg body weight on days 2 to 5 orally. Following artesunate pretreatment, groups 3, 4 and 5 rats received vitamin C (100 mg/kg), vitamin E (100 mg/kg) and a combination of both respectively orally for the 5 days. There was no significant difference in sperm viability and motility in all groups while count significantly (p<0.05) increased in group 3 animals treated with vitamin C. Serum testosterone level was significantly increased (p< 0.05) in groups 4 and 5. The MDA concentrations were significantly increased (p < 0.05) while SOD activity concurrently decreased significantly (p<0.05) in groups 2, 3, and 5 indicating an oxidative-counter oxidative relationship. It was thus concluded that artesunate at therapeutic doses and duration had no significant effect on sperm quality and serum testosterone level in male rats while vitamin C, and combination of vitamins C and E tend to promote reproductive functions in artesunate-treated male rats.Key words: Artesunate, vitamin C, vitamin E, sperm quality, superoxide dismutase activity, malondialdehyde concentration

Light Spanners

A $t$-spanner of a weighted undirected graph $G=(V,E)$, is a subgraph $H$ such that $d_H(u,v)\le t\cdot d_G(u,v)$ for all $u,v\in V$. The sparseness of the spanner can be measured by its size (the number of edges) and weight (the sum of all edge weights), both being important measures of the spanner's quality -- in this work we focus on the latter. Specifically, it is shown that for any parameters $k\ge 1$ and $\epsilon>0$, any weighted graph $G$ on $n$ vertices admits a $(2k-1)\cdot(1+\epsilon)$-stretch spanner of weight at most $w(MST(G))\cdot O_\epsilon(kn^{1/k}/\log k)$, where $w(MST(G))$ is the weight of a minimum spanning tree of $G$. Our result is obtained via a novel analysis of the classic greedy algorithm, and improves previous work by a factor of $O(\log k)$.Comment: 10 pages, 1 figure, to appear in ICALP 201

Studying the effect of variation in volume fractions of carbon fibres on mechanical and electrical properties of copper based composites

Metal Matrix Composites (MMC) belong to a class of weight efficient structural materials that are becoming popular in engineering applications especially in electronics, aerospace, aircraft, packaging and various other industries. This study focuses on the effect of varying carbon fiber wt. % on the mechanical properties of the Cu-C composite. The carbon fibers were coated with copper by electroless plating in order to increase the wettability of fibers with the copper matrix. Four compositions of copper based composite were developed by varying amount of carbon fibers. The yield strength decreases with increasing fiber size while the ultimate  tensile strength increases with increasing fiber size. Rockwell hardness test showed an increasing trend of hardness for increasing carbon fibers. The conductivity of Cu-C composite decreases by increasing carbon fibers content. Wear rate of Cu-C composite increases when carbon fiberscontent increases in the composite. SEM/EDX analysis revealed the size and distribution of fibers and indicated the fracture phenomenon.Keywords: Copper based Composites, Mechanical, Electrical and Wear Properties, Microstructur

Small sample measurements at the low energy muon facility of Paul Scherrer Institute

The low energy muon spin rotation spectroscopy (LE-$\mu$SR) is primarily used to investigate thin films, surfaces, and interfaces of materials, which has matured at the Paul Scherrer Institute (PSI) and is routinely employed by users of the low energy muon (LEM) facility. However, because of the large beam spot and low implanted muons rate, LE-$\mu$SR measurements on small samples are difficult, requiring an optimal sample size of $25\times25$ mm$^2$. Recently, we have boosted our ability to measure small samples, down to $5\times5$ mm$^2$ area, by beam collimation and tuning. This achievement is crucial for the measurements of many magnetic and superconducting materials. Furthermore, we have devised a method that allows us to measure five small area samples mounted together on the same sample plate. We expect this method to further improve the efficient use of beam time at LEM

Do topology and ferromagnetism cooperate at the EuS/Bi2_2Se3_3 interface?

We probe the local magnetic properties of interfaces between the insulating ferromagnet EuS and the topological insulator Bi$_2$Se$_3$ using low energy muon spin rotation (LE-$\mu$SR). We compare these to the interface between EuS and the topologically trivial metal, titanium. Below the magnetic transition of EuS, we detect strong local magnetic fields which extend several nm into the adjacent layer and cause a complete depolarization of the muons. However, in both Bi$_2$Se$_3$ and titanium we measure similar local magnetic fields, implying that their origin is mostly independent of the topological properties of the interface electronic states. In addition, we use resonant soft X-ray angle resolved photoemission spectroscopy (SX-ARPES) to probe the electronic band structure at the interface between EuS and Bi$_2$Se$_3$. By tuning the photon energy to the Eu anti-resonance at the Eu $M_5$ pre-edge we are able to detect the Bi$_2$Se$_3$ conduction band, through a protective Al$_2$O$_3$ capping layer and the EuS layer. Moreover, we observe a signature of an interface-induced modification of the buried Bi$_2$Se$_3$ wave functions and/or the presence of interface states