Determination and evaluation of biogas and methane productions of vegetable and fruit wastes with Hohenheim Batch Test method

Nowadays,biogas technology applications are gradually increasing worldwide due to the economic and environmental benefits.Many researches and studies related to the determination of the biogas potential of organic waste materials have been carried out in the recent years.Studies to determine the specific methane potential of organic waste materials have a great importance for both design and economical operation of the biogas plants.Energy potential that will be recovered from organic wastes is substantial in Turkey.Thanks to biogas plants gathering vegetable-fruit wastes and other organic wastes are planned to produce significant amount of renewable energy in Turkish markets.Owing to the use of organic wastes,the disposal of waste as well as energy production,soil,water and air pollution in terms of environmental protection are also minimized.On the other hand,the organic wastes produced from plants can also be utilized as fertilizer in vegetable production.In this study,the cumulative biogas and methane production of vegetable and fruit wastes were experimentally determined with HBT(Hohenheim Batch Test)method.Biogas and methane yields of vegetable and fruit wastes were found as 0.54-0.73 Nm^(3)/(kg ODM)and 0.29-0.37 Nm^(3)/(kg ODM),respectively.The highest value of the cumulative specific methane production was tomato wastes(0.37 Nm^(3)/(kg ODM)),and the lowest value was lettuce wastes(0.29 Nm^(3)/(kg ODM)),as well.The average cumulative specific methane production values of mixed vegetable and fruit wastes are determined as 0.34 Nm^(3)/(kg ODM).

Comparative Analyses of Height Growth Velocities of School Boys in South Korea and Japan in the Past 50 Years

The paper compares the height growth velocities of male schoolchildren in South Korea and Japan over the period 1961-2018. Growth in height was measured with the same birth cohorts, not by comparing mean height of ascending ages in the same year. Starting from a lower economic base and mean height in the 1960s, high school males aged 17 in South Korea became 3 cm taller in mean height than their Japanese peers in the mid-2000s versus 2 - 3 cm shorter in the 1960s through 1970s. Children in Japan ceased to grow taller by the end of the 1980s, not because they quit taking more animal-sourced foods, meat and milk, but because they had drastically steered away from fruit and vegetables in their diets since the end of the 1970s. Having largely converged economically with Japan, South Korean children ceased to grow any taller in the mid-2000s. More importantly, it was discovered in this study that successive cohorts in South Korea started to fall gradually but steadily in height growth velocity from 1st graders in middle school, aged 12 years to 3rd graders in high school, and aged 17 years, to be once again 3 cm below their Japanese peers in the early-2010s. Analysis of Korea Household Expenditure Surveys classified by age groups of household head, decomposed by the author, revealed that children under 20 years of age in South Korea began to steer away from fruit and, particularly, vegetables in their at-home consumption in the mid-1990s, to average only 15% of the level of older adults in their 50s in the mid-2010s. These results lend supports to the importance of fruit and vegetables as determinants in height and its growth velocities in two genetically similar nations over time and stages of economic growth.

Electrochemical Detection of Salicylic Acid in Pickled Fruit/Vegetable and Juice

Salicylic acid(SA)is used as a preservative in food and a biocide in some consumer products.However,in some countries its use is prohibited.The main problem in the electroanalytical determination of SA is the formation of a passive film during the electro-oxidation of SA.To alleviate the passivation during SA measurement,the experiment was conducted by screen-printed carbon electrode(SPCE).While,differential pulse voltammetry(DPV)was essential for oxidation process to provide better sensitivity.Under conditions of optimized pH and electrolyte concentration,we have calibrated SA in the range of 0.001-0.2 mM,with and LOD of 1.6μM.The relative standard deviation of the sensor responses to 40μM and 100μM SA(n=20)was<3%.SA recoveries in samples such as pickled green mustard,pickled bamboo shoots,pickled mango,pickled lime,pickle ginger and apple juice were found to be in the range of 84-113%.