Crack Mechanism of Different Concrete Grades under Compressive Loading: Application in Rigid Pavement

The growth of cracks in concretes under different loadings in various structures and their consequent diminishing effect on the lifespan of structures is an age long structural problem. This research investigates the influence of compressive loading on the crack mechanism of different concrete grades 1: 1 : 3 (M20), 1: 2: 4 (M15) and 1: 3: 6 (M10) using three brands of cements available in Nigeria namely Dangote (Type A), Elephant (Type B) and Bua (Type C). Particle Size Distribution (PSD), Aggregate Crushing Value (ACV), Aggregate Impact Value (AIV) was carried out on aggregates in accordance with relevant codes while; compressive test were performed on the hardened concrete while, the crack width was measured using microscopic technique. A coefficient of uniformity (Cu) of 4.00, AIV of 46 % and an ACV of 47.7 % were obtained for the aggregate which are suitable for rigid pavements construction. Maximum compressive strength value of 24.96 N/mm2 , 24.67 N/mm2 and 24.89 N/mm2 respectively was obtained for concrete M20 for Type A, Type B and Type C cement at the 28 day. A corresponding crack width of 0.97 mm, 0.89 mm and 0.93 mm was obtained while; a yield period of 57.66 sec, 58.33 sec and 53.33 was obtained respectively. Comparing with the International Organization for Standardization, concrete grade M20 any of the cement types is suitable for the construction of rigid pavements with heavy traffic volume while M15 is recommended for low traffic volume

Preparation and Characterization of Biochar and Activated Carbon Derived from Cashew Bagasse Waste

Biochar and Activated carbon derived from cashew bagasse waste are veritable materials produced from agro-waste. They are currently under-utilized owing to paucity of information in their recycling methods which reduces agricultural waste from the environment. This study investigates the use of under-utilized cashew bagasse waste in the production of biochar and activated carbon using pyrolysis and chemical activation methods, respectively. Cashew bagasse waste was pyrolysed at 4000C for 20mins at a heating rate of 100C per mins. The biochar produced was allowed to cool at room temperature for 30 mins. It was further reduced to smaller size particles using euro premium grinder and later sieved with 10 mesh sieve size prior to its application. The biochar was chemically activated using 0.3M Orthophosphoric acid (H3PO4) as activating agent at an impregnation ratio of 1:2.36(w/w). It was heated at 1000C to form a paste and later placed in muffle furnace at 5000C for 30 mins. This was allowed to cool and washed with distilled water until a neutral pH was obtained and later oven dried at 1050C for 24 hours to a constant weight to produce activated carbon. The produced activated carbon was kept in air tight containers prior to analysis. Characterization of pH, bulk density, moisture content, dry matter, volatile matter, and fixed carbon were determined for biochar and activated carbon. Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscopy (SEM) analysis was performed to determine the functional groups and surface morphology of biochar and activated carbon, respectively. The Data obtained were analyzed using descriptive statistics and ANOVA at P value < 0.05. The results showed that significant differences (p<0.05) were observed in the characterized parameters determined. The biochar and activated carbon has pH: (7.68±0.06 and 6.13±0.03); Bulk density :( 0.18±0.01 and 0.20±0.01) %; Moisture content: (6.67±0.33 and 16.00±0.58)%; Dry matter (93.33±0.33 and 84.00±0.58) %; Volatile matter (68.67±3.18 and 29.67±5.21) %; Fixed carbon (30.24±3.20 and 69.32±5.16) %, respectively. FTIR Analysis showed that biochar and activated carbon were more polar and also contained specific bonds. SEM analysis also indicated that biochar and activated carbon have porous structures. This study, therefore, revealed that chemically activated carbon had better characteristics than biochar produced through pyrolysis method

Promising Natural Products in Crop Protection and Food Preservation: Basis, Advances, and Future Prospects

The increase in demand for agricultural produce necessitates the continuous search for affordable, ecofriendly, readily available crop protectors, and food preservatives. Historically, the use of various chemicals was employed in controlling plant diseases and to maintain food quality. In the past few decades, several natural product-based alternatives have been discovered and projected as better alternatives to synthetic pesticides and other synthetic agrochemicals. Recent studies focusing on the application of different botanicals in crop protection and food preservation were carefully selected and reviewed. The application of plant extract in the biogenic preparation of nanoparticles was also reviewed. This review confirms that several natural products can be used as a safe replacement for synthetic agrochemicals. Different plant extracts have also served as feed for the synthesis of nanoparticle, which is increasingly applicable in crop protection and food preservation

Ferulic acid interventions ameliorate NDEA-CCl4-induced hepatocellular carcinoma via Nrf2 and p53 upregulation and Akt/PKB-NF-κB-TNF-α pathway downregulation in male Wistar rats

Hepatocellular carcinoma is a prevalent form of liver cancer that is life threatening. Many chemically synthesized anti-cancer drugs have various degrees of side effects. Hence, this study investigated the effect of FEAC interventions on NDEA-CCl4-induced HCAR in male Wistar rats. HCAR was induced by intraperitoneal administration of 200 mg/kg of NDEA and 0.5 mL/kg CCl4 (as a promoter of HCAR). Following the induction of HCAR, rats were treated differently with two different doses (25 and 50 mg/kg) of FEAC. HCAR induction was confirmed by the significant elevation of serum levels of ALT, AST, and α-FP. Also elevated significantly were liver levels of Akt/PKB, NF-κB, TNF-α, MDA, GSH, and activities of GST, SOD, and CAT, while levels of liver p53 and Nrf2 were significantly lowered compared with normal rats. Treatment interventions with both 25 and 50 mg/kg of FEAC against the DEN-CCl4-induced HCAR gave comparable effects, marked by a significant reduction in the levels of serum ALT, AST and α-FP, as well as liver levels of MDA, GSH, Akt/PKB, NF-κB, TNF-α, GST, SOD, and CAT, while levels of liver p53 and Nrf2 were significantly elevated compared with normal rats. Put together and judging by the outcomes of this study, FEAC being a potent antioxidant may also be potent against chemical-induced HCAR via upregulation of p53 and Nrf2, as well as downregulation of the Akt/PKB-NF-κB pathway in rats