Exploring HCl-HCl interactions: QZVPP calculations, improved Lennard-Jones potential, and second virial coefficient analysis for thermodynamics and industrial applications.

In this paper, we present a comprehensive analysis of HCl-HCl interactions, including QZVPP calculations, energy fitting, conformation validation, and the determination of the second virial coefficient B using improved Lennard-Jones (ILJ) potential parameters. To acquire accurate interaction energies, initial QZVPP calculations are performed on approximately 1851 randomly generated HCl-HCl conformations. Then, these energies are used to fit an improved Lennard-Jones potential energy surface, allowing for a robust description of HCl-HCl interactions. The ILJ potential parameters are then used to validate particular HCl dimer conformations, ensuring their stability and consistency with experimental observations. The correlation between calculated and experimental conformations strengthens the validity of the ILJ potential parameters. In addition, the second viral coefficient B is calculated at various temperatures using the ILJ potential. The obtained B values are compared to experimental data, demonstrating close agreement, and validating the ILJ potential's ability to accurately capture the intermolecular interactions and gas-phase behavior of the HCl-HCl system. The results of this study demonstrate the effective implementation of QZVPP calculations, energy fitting, and ILJ potential parameters in validating HCl-HCl conformations and accurately determining the second virial coefficient B. The high degree of concordance between calculated B values and experimental data demonstrates the validity of the ILJ potential and its suitability for modeling HCl-HCl interactions. This research contributes to a greater comprehension of HCl-HCl interactions and their implications for numerous chemical and atmospheric processes. The validated conformations, energy fitting method, and calculated second virial coefficients provide valuable instruments for future research and pave the way for more accurate modeling and simulations of HCl-HCl systems.

Exploring the adsorption behavior of molecular hydrogen on CHA-zeolite by comparing the performance of various force field methods.

Molecular hydrogen (H2) adsorption plays a crucial role in numerous applications, including hydrogen storage and purification processes. Understanding the interaction of H2 with porous materials is essential for designing efficient adsorption systems. In this study, we investigate H2 adsorption on CHA-zeolite using a combination of density functional theory (DFT) and force field-based molecular dynamics (MD) simulations. Firstly, we employ DFT calculations to explore the energetic properties and adsorption sites of H2 on the CHA-zeolite framework. The electronic structure and binding energies of H2 in various adsorption configurations are analyzed, providing valuable insights into the nature of the adsorption process. Subsequently, force field methods are employed to perform extensive MD simulations, allowing us to study the dynamic behavior of H2 molecules adsorbed on the CHA-zeolite surface. The trajectory analysis provides information on the diffusion mechanisms and mobility of H2 within the porous structure, shedding light on the transport properties of the adsorbed gas. Furthermore, the combination of DFT and MD results enables us to validate and refine the force field parameters used in simulations, improving the accuracy of the model, and enhancing our understanding of the H2-CHA interactions. Our comprehensive investigation into molecular hydrogen adsorption on CHA-zeolite using density functional theory and molecular dynamics simulations yields valuable insights into the fundamental aspects of the adsorption process. These findings contribute to the development of advanced hydrogen storage and separation technologies, paving the way for efficient and sustainable energy applications.

Risk Factors And Treatment Outcome Of Children With HCV Infection.

BACKGROUND: Combination of pegylated interferon α-2a or α-2b has been considered to be the standard for treating HCV infection among children. Many new agents inhibiting HCV during various steps while replicating is under study around the world. This study was aimed to note the efficacy of sofosbuvir and ribavirin among children having HCV infection. METHODS: This was an open label experimental trail done at Department of Gastroenterology, Children Hospital and The Institute of Child Health, Multan. The study duration was from July to December 2019. A total of 89 HCV treatment naïve children aged 6-16 years of age, having HCV PCR as positive were enrolled. Sofosbuvir as 400 mg once a day along with ribavirin 10-15 mg per kg per day in the form of once or twice as divided doses were given in all the cases. After starting the treatment, along with side effects, rapid virological response (RVR) as PCR at 4 weeks, early virological response (EVR) at 12 weeks and post treatment 12 weeks HCV PCR as sustained virological response (SVR) was noted. RESULTS: Out of a total of 89 children, there were 53 (59.6%) boys and 36 (40.4%) girls. Mean age was noted to be 12.42±2.57 years. Majority of the children, 72 (80.9%) had genotype 3 while genotype 1 was noted in 11 (12.4%) and un-typable in remaining 6 (6.7%). History of blood or blood products transfusion was seen to be the commonest mode of HCV transmission, found in 41 (46.1%) children, perinatal transmission in 20 (22.5%) and history of previous surgery in 9 (10.1%). Rapid virological response was noted in 73 (83.1%) children, all 89 (100%) children achieved EVR whereas SVR was noted in 86 (96.7%). Headache was the commonest side effect, reported by 24 (27.0%) followed by nausea in 15 (16.9%). CONCLUSIONS: Regardless of the genotype, sofosbuvir and ribavirin combination therapy was noted to have excellent efficacy amongst children with HCV infection. History of blood and blood product transfusion was the commonest risk factor found.

Etiologies and outcome of lower gastrointestinal bleeding in patients presenting to a tertiary care Children's Hospital.

OBJECTIVE: To determine etiology and outcome of children with lower gastrointestinal bleeding (LGIB). METHODS: This was a prospective study conducted at the Department of Pediatric Gastroenterology and Hepatology, Children's Hospital and The Institute of Child's Heath, Multan, Pakistan, from July 2019 to March 2020. A total of 148 cases presented with bleeding per rectum and underwent colonoscopy, were included. Children of both genders and aged three month to 15 years were included. Detailed history, clinical examination, laboratory studies, colonoscopy and histopathology were done in all cases. Study information like demographics, complaints, general clinical examination, colonoscopy and histopathological findings were recorded. RESULTS: Overall, mean age was noted to be 7.20±1.83 years. Abdominal pain was reported in 41 (27.7%), diarrhea 36 (24.3%), fever 12 (8.1%) and constipation in 4 (2.7%). Pallor was noted among 68 (45.9%), weight loss 39 (26.3%) and tachycardia 31 (20.9%). Colonoscopy revealed juvenile colonic / rectal polyps, infectious colitis and solitary rectal ulcer (SRU) as the most common etiologies found among 58 (39.2%), 20 (13.5%) and 19 (12.8%) cases respectively. Juvenile polyps and non-specific colitis were the commonest histopathological findings seen in 55 (37.2%) and 20 (13.5%) cases respectively. Colonoscopic polypectomy was used to remove all juvenile polyps. CONCLUSION: LGIB is presentation of various underlying causes. Children with LGIB commonly present with abdominal pain. Juvenile polyps were the most frequent cause of LGIB among children flowed by non-specific colitis. Most of the children having LGIB were diagnosed and treated successfully, few are in remission and very few were found resistant to treatment.