Synthesis of a resorcinol-based derivative as a corrosion inhibitor for low-carbon steel in 0.5 mol L-1 HCl medium: chemical, electrochemical, and theoretical aspects.

This work illustrated the synthesis of a new simple resorcinol derivative, 4,6-dimethoxyisophthalohydrazide (DMIH) and confirmed its structure using 1H-NMR spectroscopy. The inhibiting performance of the DMIH compound in resisting the pitting action of a 0.5 mol L-1 HCl solution on low-carbon steel (LCS) was assessed. The newly synthesized compound had a simple structure and was dissolved in acidic media. The efficiency of the inhibitor was examined using chemical and electrochemical methods. The DMIH compound significantly decreased the rate of dissolution of LCS in HCl solution by adsorption. The adsorption was based on the Langmuir model. The DMIH compound is adsorbed on LCS via both chemisorption and physisorption. The DMIH compound is a mixed-type inhibitor. An inhibition efficiency (IE) of 83.8% was obtained using 300 ppm of the DMIH compound at 298 K. The IE decreased to 72% as the temperature increased to 328 K. When the concentration of DMIH increased from 50 to 300 ppm, the charge transfer resistance (R ct) increased from 134.7 to 404.8 ohm cm2, and the capacitance of the adsorbed layer decreased from 38 × 10-6 to 11 × 10-6 F cm-2. The high IE of the synthesized inhibitor was validated by the quantum characteristics. Monte Carlo (MC) simulations revealed that the DMIH compound adsorbed to the LCS quite well. The presence of a protective film on the LCS specimen was verified by the scanning electron microscopy (SEM) and atomic force microscopy (AFM) results. DMIH has significant potential to function as a corrosion inhibitor, as indicated by the comparative study between its performance and that of previously reported compounds. Although the structure of the DMIH compound is simpler than that of other inhibitors, it has been proven to be more effective.

The gametogenic cycle and spawning of the short-necked clam, Paphia undulata Born, 1778 (Bivalvia: Veneridae) from Timsah Lake, Suez Canal, Egypt.

BACKGROUND: Paphia undulata, The Short-Necked Clam, is an edible marine bivalve that is consumed internationally and locally in Egypt. Overfishing and pollution have caused population declines in Egyptian fisheries during the last decade. Accurate reproductive biology knowledge is critical for designing long-term exploitation strategy for this resource. P. undulata spawning and gametogenic cycle research were carried out from January to December 2020 along Timsah Lake, Suez Canal, Egypt. RESULTS: These clams are functionally dioecious with a very low incidence of hermaphroditism. The sex ratio of the clam population was 1.0:1.07:0.04 for male, female and hermaphrodite respectively. The shell lengths of the collected clams were 4.64 ± 0.83 cm in males, 4.55 ± 0.9 cm in females and 4.19 ± 0.3 cm in hermaphrodite clams. The sizes at the onset of sexual maturity in both males and females were 2.1 cm and 2.5 cm respectively. CONCLUSIONS: Reproductive studies revealed that this species has a prolonged spawning season that is not restricted to a specific period.

Effect of Ramadan fasting on chronic inflammation markers and gut bacterial endotoxins among Egyptian hemodialysis patients.

BACKGROUND: Chronic kidney disease (CKD) is associated with a state of chronic inflammation. This study aimed to investigate effects of Ramadan fasting on the markers of chronic inflammation and gut bacterial endotoxin levels in maintenance hemodialysis. METHOD: A prospective self-controlled observational study included 45 patients. Serum levels of High Sensitive CRP (hsCRP), indoxyl sulfate, and trimethylamine-n-levels were measured within a week before and a week after Ramadan fasting. RESULTS: Twenty-seven patients have fasted more than 15 days (29 ± 2.2 days). The levels of high sensitive C-reactive protein (hsCRP) (median of 62 mg/L vs. 91 mg/L), trimethylamine-n-oxide (TMAO) (median of 4.5 µmoL/L vs. 17 µmoL/L), platelet-to-lymphocyte ratio (PLR) (mean of 98.9 mg/L vs. 111.8 mg/L) and neutrophil-to-lymphocyte ratio (NLR) (median of 1.56 vs. 1.59) were significantly lower after Ramadan fasting with p < 0.001, p < 0.001, p < 0.001, and p = 0.04, respectively. CONCLUSION: A beneficial effect of Ramadan fasting on levels of bacterial endotoxins and markers of chronic inflammation in hemodialysis patients was observed.

Rapid and Simple Method for Measuring Petroleum Asphaltenes by the Centrifugation Technique.

Asphaltenes are heavy constituents of crude oil which affect the flow and viscosity of crude oil. They also stabilize water-in-oil emulsions which makes the separation process of water from oil during the primary treatment processes for crude oils more difficult and costly. Measuring asphaltenes has great importance, especially for crude oil production companies. Gravimetric and spectroscopic measurement methods are the basic techniques used by international references such as ASTM and IP. A new methodology has been introduced as a modification of ASTM D6560 gravimetric methodology by using the centrifugation technique in the separation of asphaltenes for different oil samples with the API gravity change from 17.4 (oil S1) to 39.8 (oil S5). The new methodology has the advantages of consuming little time, and multiple sample processing and can be done in the field and also in the lab. Moreover, it has good repeatability, reproducibility, and working range values compared to the reference gravimetric ASTM and IP methods. The repeatability of the new method was found to be 8.0% at its maximum value (S1, has a low asphaltene content), while the minimum value was found to be 3.75% (S10, has the highest asphaltene content). It was found that the maximum reproducibility value was 17.0% for the S1 sample and the minimum was 0.0% for S9 and S10 samples.

Resorcinol Derivative as an Environmentally Friendly Low Carbon Steel Inhibitor in HCl Medium.

An ecofriendly resorcinol derivative, dimethyl-4,6-dihydroxyisophthalate (DDIP) is examined as an anticorrosion agent for low carbon steel (CS) in a 0.5 mol L-1 HCl solution. Electrochemical and chemical methods are used to determine the effectiveness of the inhibitor. The DDIP compound decreased the rate of CS corrosion. The mitigation efficiency rose from 61.8 to 79.9% as the DDIP dose increased from 50 to 300 ppm in the corrosive medium. At 300 ppm, however, the efficiency decreased from 79.9 to 70.05% as the temperature increased from 25 to 55 °C. Physical quantities and thermodynamic parameters are discussed. The compound's adsorption follows Langmuir's concept. Adsorption of the DDIP compound is a mix of physisorption and chemisorption. The difference in E corr values is less than 85 mV, indicating that the examined compound is a mixed-type inhibitor. Scanning electron microscopy and atomic force microscopy revealed the development of a coherent film at CS in the presence of the DDIP inhibitor. The results obtained using various techniques were closely related, indicating validity and accuracy. The interaction between the DDIP molecules and the CS was explained by the density functional theory and Monte Carlo simulation. The quantum characteristics confirmed that the DDIP compound is a promising inhibitor.

Effect of blending biodiesel produced from waste cooking oil on the properties of residual fuel oil: energy saving and the economic cost.

The mazout properties were improved using ecofriendly ways because of its wide range of applications, abundance and low cost. In this study, the effect of biodiesel blending on the properties of mazout was investigated. Biodiesel was prepared from waste cooking oil. The mazout properties such as viscosity and density improved with the increase in volume ratio of biodiesel to mazout. The mazout viscosity decreases with an average value of 12% as the biodiesel is added with a volume ratio of 10%. In contrast, when a 10% volume ratio of the biodiesel is added to mazout, the heating value decreases by 1.5%. Although the calorific value of mazout decreases after the blending process, the blending method is considered a method that saves energy compared to the heating method to reduce the viscosity. The cost of improved mazout depends on the cost of biodiesel production. The more the cost of biodiesel production approaches the cost of mazout, the more expensive the use of the blending method compared to the heating method. Moreover, the blending method is a very effective method to reduce the percentages of harmful compounds such as sulfur, and the compound percentages that occupy volumetric proportions of fuel such as water content.

Effect of Ramadan Fasting on Chronic Inflammation and Body Composition in Patients with Chronic Kidney Disease.

Chronic kidney disease (CKD) is associated with a state of chronic inflammation which is responsible for many of the pathophysiological changes detected in these patients. Many studies have evaluated the effect of Ramadan fasting on renal function and cardiovascular morbidity in CKD patients, but the effect of Ramadan fasting on markers of chronic inflammation was not previously assessed. This study aimed to evaluate the effect of Ramadan fasting on some markers of chronic inflammation in CKD patients with estimated glomerular filtration rate (eGFR) less than 60 mL/min/1.73 m2 body surface area and not on dialysis. This was a pilot study that included 20 patients (8 males and 12 females), mean age 61.9 years with CKD (eGFR <60 mL/min/1.73 m2 body surface area not on dialysis) who fasted the whole lunar month of Ramadan. Complete blood count, neutrophil-to-lymphocyte ratio (NLR), platelet-to-lymphocyte ratio (PLR), high-sensitive C-reactive protein (hs-CRP), serum creatinine (SCr), eGFR, serum albumin, body weight, body mass index (BMI), and body composition assessed by bioimpedance analysis were assessed before and after Ramadan fasting. Ramadan fasting was not associated with significant change of SCr (P = 0.132), eGFR (P = 0.097), serum albumin (P = 0.352), body weight (P = 0.445), BMI (P = 0.168), body fat (P = 0.979), visceral fat (P = 0.163), muscle mass (P = 0.662), or body water (P = 0.815). There was a statistically significant decrease of markers of chronic inflammation including NLR (P = 0.003), PLR (P = 0.005), and hs-CRP (P = 0.000) after Ramadan fasting. Ramadan fasting was associated with improvement of the state of chronic inflammation in CKD patients (eGFR below 60 mL/min/1.73 m2 body surface area). Ramadan fasting was not associated with a significant change of body composition or deterioration of renal function tests in CKD patients.

Effect of Ramadan fasting on arterial stiffness parameters among Egyptian hypertensive patients with and without chronic kidney disease.

Arterial stiffness (AS) increases progressively in patients with chronic kidney disease (CKD). It is a strong predictor of cardiovascular and all-cause mortality. This study aims at evaluate of the effect of Ramadan fasting on AS parameters, augmentation index (AIx), and pulse wave velocity (PWV) in hypertensive patients with and without CKD. A cohort of 71 patients (mean age = 57.14 ± 14.5 years, 42 females and 29 males) were enrolled in this study; 34 with CKD and 37 without CKD. All patients had hypertension, while 25 patients had diabetes mellitus. Serum creatinine (Cr), serum urea, estimated glomerular filtration rate (eGFR) by CKD-EPI formula, brachial and central systolic blood pressure (BSP and CSP respectively), brachial and central diastolic blood pressure (BDP, CDP, respectively), AIx and PWV (measured by cuff based oscillometric method) were assessed before and after Ramadan fasting. In patients without CKD BSP, BDP, CSP, and CDP significantly decreased (P = 0.0001, 0.0001, 0.0001, and 0.0001, respectively). In patients with CKD BSP and CSP significantly decreased (P = 0.005 and 0.005), while BDP and CDP decreased, but the change was not statistically significant. AIx significantly decreased in patients without CKD (P = 0.0001, mean 36.24 before and 26.22 after Ramadan fasting), but did not significantly change in patients with CKD (P 0.381 mean 25.94 before and 25 after Ramadan fasting). PWV decreased in both groups, but the change was not significant. Serum Cr significantly increased (P = 0.03 mean 1.06 mg/dL before and 1.11 mg/dL after Ramadan fasting), while eGFR did not significantly decrease (P = 0.072, mean 69.73 mL/ min/1.73 m2 before and 67.3 mL/min/1.73 m2 after Ramadan fasting) in patients without CKD. Serum Cr significantly decreased (P 0.028 mean 1.93 mg/dL before and 1.87 mg/dL after Ramadan fasting) and eGFR significantly increased (P 0.006 mean 32.65 mL/min/1.73 m2 before and 34.68 mL/min/1.73 m2 after RF) in patients with CKD. Ramadan fasting is associated with improved peripheral and central blood pressure control in hypertensive patients with and without CKD. It is also associated with improved arterial compliance (decreased AIx) in hypertensive patients without CKD.

Synthesis and Biological Activities of Some New Benzotriazinone Derivatives Based on Molecular Docking; Promising HepG2 Liver Carcinoma Inhibitors.

In one-pot strategy, diazotization of methyl anthranilate 5 followed by addition of amino acid ester hydrochloride, we have prepared methyl-2-(4-oxobenzotriazin-3(4H)-yl)alkanoates 6a-c. Starting with hydrazides 7a,b, N-alkyl-2-(4-oxobenzotriazin-3(4H)-yl)alkanamides 9-10(a-h) and methyl-2-(2-(4-oxobenzotriazin-3(4H)-yl)alkanamido)alkanoates 11-12(a-e) were prepared via azide coupling. Hydrazones 13-15 were prepared via condensation of hydrazides 7a,b with 4-methoxybenzaldehyde, 4-dimethylaminobenzaldehyde, and/or arabinose. Molecular docking was done for synthesized compounds using MOE 2008-10 software. The compounds 9a, 12a, 12c, 13a, 13b, and 14b have the most pronounced strong binding affinities toward the target E. coli Fab-H receptor, whereas compounds 3, 11e, 12e, and 13a have the most pronounced strong binding affinities toward the target vitamin D receptor. The in vitro antibacterial activities of the highest binding affinity docked compounds were tested against E. coli, Staphylococcus aureus, and Salmonella spp. Majority of the tested compounds showed effective positive results against E. coli, while they were almost inactive against Staphylococcus aureus and Salmonella spp . The in vitro cytotoxic activities of the highest binding affinity-docked compounds were tested against the human liver carcinoma cell line (HepG2). Some compounds showed potent cytotoxic activity with low IC50 values, especially for 3 (6.525 µM) and 13a (10.97 µM) than that for standard drug doxorubicin (2.06 µM).