Physical and Mechanical Properties Evolution of Coal Subjected to Salty Solution and a Damage Constitutive Model under Uniaxial Compression

Many underground reservoirs for storing water have been constructed in China’s western coal mines to protect water resources. Coal pillars which work as dams are subjected to a long-term soaking environment of concentrated salty water. Deterioration of the coal dam under the attack of the salty solution poses challenges for the long-term stability and serviceability of underground reservoirs. The evolution of the physical and mechanical properties of coal subjected to salty solutions are investigated in this paper. Coal from a western China mine is made to standard cylinder samples. The salty solution is prepared according to chemical tests of water in the mine. The coal samples soaked in the salty solution for different periods are tested by scanning electron microscope, nuclear magnetic resonance, and ultrasonic detector techniques. Further, uniaxial compression tests are carried out on the coal specimens. The evolutions of porosity, mass, microstructures of coal, solution pH values, and stress–strain curves are obtained for different soaking times. Moreover, a damage constitutive model for the coal samples is developed by introducing a chemical-stress coupling damage variable. The result shows that the corrosion effect of salty solution on coal samples becomes stronger with increasing immersion time. The degree of deterioration of the longitudinal wave velocity (vp) is positively correlated with the immersion time. With the increase in soaking times, the porosity of coal gradually increases. The relative mass firstly displays an increasing trend and then decreases with time. The peak strength and elastic modulus of coal decreases exponentially with soaking times. The developed damage constitutive model can well describe the stress–strain behavior of coal subjected to salty solution under the uniaxial compression.

Detection and Characterization of the Soybean Allergen Gly m 7 in Soybeans and Processed Soybean Foods

Gly m 7, a novel soybean allergen, was recently reported. In this study, we attempted to detect Gly m 7 in various soybeans and processed soybean foods using raised anti-Gly m 7 antibodies and enzyme-linked streptavidin, specifically binding to the biotin moiety of Gly m 7. There was a large difference in Gly m 7 levels in various soybean-processed foods. When Gly m 7 levels were determined, all cultivars contained this allergen almost completely, but the biotin moiety detected by streptavidin varied, suggesting that biotinylated levels of Gly m 7 might differ among cultivars. The thermal stability of Gly m 7 was determined by heating soybean extracts. During detection using anti-peptide antibodies, detectable intact Gly m 7 was gradually reduced by heating. Gly m 7 was not detected by peptide or biotin detection in worm-wounded soybeans. Soybeans were immersed in distilled water as a pretreatment step for germination, and Gly m 7 levels were compared by immersion time (4–96 h). Intact Gly m 7 was rapidly degraded in detection by both peptide and biotin moieties. This suggested that Gly m 7 was degraded by some protease(s) during germination. These results would be useful for understanding the properties or risk assessment of Gly m 7, a newly discovered soybean allergen.

The Anthelmintic Activity Of Etanol Extract of Porang Tubers Against Fasciola gigantica In Vitro

This study aims to determine the anthelmintic activity ethanol extract of porang tubers (A. oncophillus) against F. gigantica worms in vitro. There were five treatments and each treatment was done in five replications and used 10 F. gigantica. The treatments of this research were K- with CMC Na 1%, K+ with Albendazole 2.4 mg/ml, P1 with extract concentration 5%, P2 with extract concentration 10%, P3 with extract concentration 20%. The results showed that the extract of Porang tuber (A. oncophillus) had an anthelmintic effect against F. gigantica worms in vitro. In the extract with a concentration of 20%, there were anthelmintic properties that almost the same as Albendazole. The higher the extract concentration, the higher the anthelmintic properties. The longer the immersion time, the higher the number of dead worms. The morphological changes was evaluated by light microscopic examination and the results showed many histopathological changes on the morphology of F. gigantica. The results indicate that the possible use of the tubers as a potential anthelmintic against F. gigantica.

Influence of Water Immersion on Stability of AC-WC Mixed with Gondorukem Additional Material

One of the treatments that can be given to asphalt mixtures to determine the durability of the mixture is by water immersion. This study aims to analyze the stability value of Marshall mixture of AC-WC (Asphalt Concrete Wearing Course) by using modified Asbuton as a binder and gondorukem as added material due to water immersion. The method used in this research is experimental in the laboratory. AC-WC mixture is produced using modified Asbuton as a binder (Retona Blend 55) at optimum asphalt content of 6.25% and gondorukem as an additive at 0.0% and 2.5% content. The treatment given to the mixture is by soaking water for 0, 1, 3 and 7 days. The treatment given to the mixture is by soaking water for 0, 1, 3 and 7 days. The results showed that the Marshall stability value decreased with increasing water immersion time. Decrease in Marshall stability values that occur in specimens with immersion time of 1, 3 and 7 days for specimens without immersion are 21.34%, 25.56% and 28.25%, respectively.

Processing of Gelatin from the Skin of Pangasius hypopthalmus Using Papain Enzyme

This study aimed to determine the processing of gelatin of catfish skin using the papain enzyme in 3 different concentrations. The method used was an experiment with a factorial Completely Randomized Design (CRD). The experiment consisted of 2 factors, namely papain enzyme concentration and the immersion time of the enzyme with 3 replications. The first factor consisted of 3 levels, namely the use of papain enzymes P1 (2%), P2 (4%) and P3 (6%). The second factor, the immersion time consisted of 3 levels of 25 minutes (W1), 35 minutes (W2) and 45 minutes (W3). The data were analyzed by using CRD. The results showed that the combination of P2W1 showed the best viscosity and gel strength (6.77 CP and 115.17 g bloom).

Improving germination with pre-sowing technique on Caliandra calothyrsus Meissn

Red Calliandra (Caliandra colothyrus) is a high-quality energy wood raw material that can be produced rapidly. It’s ideal for making wood pellets. The need for wood pellets is on the increase globally. For the production of wood pellets continuity, sufficient materials were required, requiring the development of red calliandra cultivation. The long duration of the seed germination process due to the hard seed coat is an obstacle in the generative propagation of red calliandra. This study aimed to determine the best treatment for red calliandra dormancy breaking and simultaneous germination. A factorial fully randomized design (F-CRD) with two treatment factors was used in this study. The first factor is type of solution (P) with three levels consisting of: P1: soaking in water; P2 : immersion with MSG solution (12 grams/liter); P3 : immersion in young coconut water (100%). The second factor is the length of immersion time (T) with three levels consisting of: T1: soaking time for 8 hours; T2 : immersion time for 12 hours; T3 : immersion time for 16 hours. Each treatment consisted of 20 seeds, which were replicated three times for a total of 540 seeds. The initial day of germination, length of germination, percentage of germination, and germination rate index were all measured. The results showed that that the most optimal germination for red Calliandra found in the P1T1 treatment (soaking in water for 8 hours). It can be shown from all observed parameters

Penggunaan Air Kelapa Muda Sebagai Zat Pengatur Tumbuh Terhadap Daya Kecambah, Vigoritas, Berat Kering Biji Tanaman Kelor (Moringa oleifera)

The more common methode for planting moringa plant is using seed, because this plant produces a lot of seeds. However, the resulting seeds have a hard enaugh seed coat so that. These conditions can affect and even thwart germination, vigor and growth of the plant. This Study aims to determine the proper dosage of young coconut water to be used in growing moringa seeds, so that later it become a recommendation for formers in the development of moringa plants. This research was conducted using a green house and laboratory scale method with the media that had been prepared for germination obsevations were carried out for two weeks to obtain data according to the observed parameters which included capacity, Vigority and dryweight of moringa plants. The result of the analysis of variety showed that the concentration of young coconut water had no significant effect (P>0.05) on the germination, vigor and dryweight of moringa plants. Likewise, the interaction between immersion time and coconut water concentration had no significant effect (P>0.05) on the observed variables. This situation is due to the fact that not all moringa seeds undergo the imbibition process properly so that they effect the observed variables.

The Durability of the AC-BC Mixture Using Stone of Baba Mount, Tana Toraja Regency

Several factors that can affect road damage are excessive traffic load, temperature (weather), water, and pavement construction that does not meet the technical requirements. The durability of an asphalt mixture is the resistance of the mixture to the effects of water, water vapor, and temperature. A mixture with a high durability value provides a good mix quality and long-term use. The purpose of this study was to determine the durability of the AC-BC mixture using Mount Baba stone. The general specifications of Bina Marga in 2018 are the reference in this study. By using the standard Marshall test method, the results obtained through the Marshall AC-BC mixture immersion test with a duration of immersion time of 0.5 hours, 12 hours, 24 hours, 36 hours, 48 hours, 60 hours with a durability value of 95.49% - 86.99%. The increase in immersion time causes a decrease in the durability of the mixture.

Investigating the Inhibitive Characteristics of Moringa Oleifera on the Corrosion of Mild Steel

This work deals with the inhibitive characteristics of Moringa oleifera fruits and leaves extracts in Hydrochloric Acid solution and Sodium Hydroxide solution respectively on the corrosion of mild steel. This was carried out using weight loss and polarization techniques. The effects of immersion time, the effect of acid and alkaline concentration on the corrosion behavior of mild steel in 1.0M HCl and 1.0 NaOH with addiction of extracts were deduced. The fruits which were dried and grounded to powder of 10g and the leaves which range from 25cm3 to 100cm3 were used for this study. The corrosion rate was very high in the absence of inhibitors (Moringa oleifera fruits and the leaves extracts). The mild steel was cut into coupon averaging a total surface area of 4.262cm2 . The sample was weighed and immersed into a beaker containing 1.0M NaOH with different volumes of moringa leaves and 1.0M HCl with 10g dried concentrated powdered moringa fruits with coupons removed every 7 days for weight loss measurements till 4 weeks. The corrosion rates were found to be decreased by 83% in 1.0M HCl and 78% in 1.0M NaOH respectively, values of inhibition efficiency (ࣁ (%were calculated from weight loss. The results obtained showed that the Moringa oleifera fruits and leaves extracts could serve as effective inhibitors on the corrosion of mild steel in HCl and NaOH respectively. Keywords: Moringa oleifera, Corrosion rate, Weight loss, Mild steel, Inhibitor.