Measurement Of Nutrients In Green House Soil With Laser Induced Breakdown Spectroscopy

Laser-induced breakdown spectroscopy (LIBS) has been applied for the determination of nutrients in the green house soil samples. We determined appropriate spectral signatures of vital nutrients and calibrated the method to measure the nutrients in a naturally fertilized plot, cultivated with tomato and cucumber plants. From the calibration curves we predicted the concentrations of important nutrients such as Ca, K, P, Mg, Fe, S, Ni and Ba in the soil. Our measurements proved that the LIBS method rapidly and efficiently measures soil nutrients with excellent detection limits of 12, 9, 7, 9, 7, 10, 8 and 12~mg/kg for Ca, K, P, Mg, Fe, S, Ni and Ba respectively with a precision of 2%, The unique features of LIBS for rapid sample analysis demonstrated by this study suggests that this method offers promise for precision measurements of soil nutrients as compared to conventional methods in short span of time.     

Genotype-dependent effect of exogenous 24-epibrassinolide on chromium-induced changes in ultrastructure and physicochemical traits in tobacco seedlings

Environmental Science and Pollution Research - Greenhouse hydroponic experiments were carried out using three different heavy metal accumulation tobacco genotypes to evaluate how different...     

Graphene and its derivatives: synthesis,modifications, and applications in wastewater treatment

Graphene was discovered in 2004 and has attracted intensive interests because of its unique mechanical, electric, thermal, optical, and structural properties, which makes graphene a potential candidate for various applications. Graphene is being used as a composite or filler material with metals, metal oxides, and polymers for potential advanced applications in solar cells, lithium-ion batteries, photocatalysis and sensing. These applications depend upon the distinctive properties of graphene, which in turn depend on the adopted synthetic approach. This article reviews the recent developments in synthesis of graphene and related composite materials. The synthesis of graphene through exfoliation, epitaxial growth and direct growth via carbon source, and modification approaches by covalent and noncovalent methodologies are discussed. Graphene-based metal and metal oxide composites for the purification of wastewater using photolytic process are also presented.     

Evaluation of toxic effects induced by arsenic trioxide or/and antimony on autophagy and apoptosis in testis of adult mice

Environmental Science and Pollution Research - Arsenic trioxide (ATO) and antimony (Sb) are well-known ubiquitous environmental contaminants and cause unpromising male reproductive effects in...     

Toward environmental sustainability: how do urbanization,economic growth,and industrialization affect biocapacity in Brazil?

The South American country Brazil is one of the richest countries in terms of natural resources, representing 14 percent of the world’s total biocapacity. However, the biocapacity (biosphere’s ability to generate resources and sequester waste) per capita in Brazil has shown a massive decline over the last five decades, while economic growth and urbanization have rapidly increased for the same period. Brazil is one of the largest creditors of biocapacity to the world, and biocapacity loss in Brazil can lead to devastating environmental consequences. Therefore, this work empirically investigates the influence of urbanization, economic growth, and industrialization on biocapacity controlling human capital from 1961 to 2016 in Brazil. The Bayer and Hack cointegration test, the Autoregressive Distributed Lag (ARDL) technique, and Hacker and Hatemi-J (J Econ Stud 39:144–160, 2012) causality tests are employed. The findings unfolded a U-shaped relationship between economic growth and biocapacity, evidencing that economic growth reduces biocapacity, but after achieving a threshold level, it promotes biocapacity. Urbanization has a negative relationship with biocapacity per capita, indicating that urbanization is a significant driver of the biocapacity loss in Brazil. Further, urbanization and economic growth Granger cause biocapacity. Lastly, relevant policy implications are proposed to overcome the reduction in biocapacity.

     

CDES: A pixel-based crowd density estimation system for Masjid al-Haram

CDES is an automatic crowd density estimation system that can be used to estimate crowd density from digital images taken at Masjid al-Haram. Developed using a combination of image processing and artificial intelligence (AI) technologies, CDES possesses the capability to count the number of people in moderately high crowds from a flexibly selected region of interest (ROI). Background removal and edge detection are first applied to the image for crowd feature extraction. Then, the extracted crowd foreground blob pixels are scaled accordingly to correct perspective distortion. Finally, the corrected pixel blobs act as input for the backpropagation (BP) neural network to estimate the number of people within the blob. Using the area of the selected ROI, the crowd density is calculated and classified into five ranges from very low to very high. The experimental results are presented.     

Residual effects of tobacco biochar along with different fixing agents on stabilization of trace elements in multi-metal contaminated soils

The residual effect of tobacco biochar(TB ≥ 500°C) mono and co-application with Cahydroxide(CH),Ca-bentonite(CB) and natural zeolite(NZ) on the bio-availability of trace elements TE(s) in alkaline soils has not been deeply studied yet.A pot study that had earlier been investigated TB mono and blended with CH,CB and NZ on the immobilization of Pb,Cu Cd,and Zn by Chinese cabbage.Maize crop in the rotation was selected as test plant to assess the residual impact of amendments on stabilization of Pb,Cu Cd,and Zn in mine polluted(M-P),smelter heavily and low polluted(S-HP and S-LP,respectively) soils.The obtained results showed that stabilization of Pb,Cd,Cu and Zn reached 63.84% with TB + CB,61.19% with TB + CH,83.31% with TB + CH and 35.27% with TB + CH for M-P soil,36.46% with TB + NZ,38.46% with TB + NZ,19.40% with TB + CH and 62.43% with TB + CH for S-LP soil,52.94% TB + NZ,57.65% with TB + NZ,52.94% with TB + NZ,and 28.44% with TB + CH for S-LP soil.Conversely,TB + CH and TB alone had mobilized Pb and Zn up to19.29% and 34.96% in M-P soil.The mobility of Zn reached 8.38% with TB + CB and 66.03%with TB for S-HP and S-LP soils.The uptake and accumulation of Pb,Cd,Cu and Zn in shoot and root were reduced in three polluted soils.Overall,the combination of TB along with CH,CB and NZ has been proven to be effective in Pb,Cd,Cu and Zn polluted mine/smelter soils restoration.     

Experimental investigation of tribological characteristics and emissions with nonedible sunflower oil as a biolubricant

Plant (vegetable) oil has been evaluated as a substitute for mineral oil–based lubricants because of its natural and environmentally friendly characteristics. Availability of vegetable oil makes it a renewable source of bio-oils. Additionally, vegetable oil–based lubricants have shown potential for reducing hydrocarbon and carbon dioxide (CO₂) emissions when utilized in internal combustion (IC) engines and industrial operations. In this study, sunflower oil was investigated to study its lubricant characteristics under different loads using the four-ball tribometer and the exhaust emissions were tested using a four-stroke, single-cylinder diesel engine. All experimental works conformed to American Society for Testing and Materials standard (ASTM D4172-B). Under low loads, sunflower oil showed adequate tribological characteristics (antifriction and antiwear) compared with petroleum oil samples. The results also demonstrated that the sunflower oil–based lubricant was more effective in reducing the emission levels of carbon monoxide (CO), CO₂, and hydrocarbons under different test conditions. Therefore, sunflower oil has the potential to be used as lubricant of mating components.

Implications: An experimental investigation of the characteristics of nonedible sunflower oil tribological behaviors and potential as a renewable source for biofluids alternative to the petroleum oils was carried out. The level of emissions of a four–stroke, single-cylinder diesel engine using sunflower oil as a biolubricant was evaluated.     

Bacteriological quality of spring water in Bahrain

Summary The bacteriological quality of untreated spring waters in Bahrain were evaluated. Samples were collected from 12 natural springs and analysed for total plate count, total coliform, total faecal coliform, total faecal streptococci and occurrence ofShigella andSalmonella. The total bacterial counts ranged from 2.4×10¹ to 1.6×10⁴ CFU mL^–1 with an average of 2.8×10³.The coliform organisms were present in all springs. Faecal coliforms were present in 11 out of 12 springs studied, and three springs were heavily contaminated. Based on criteria which used the ratio of faecal coliform to faecal streptococci, all springs studied may be contaminated with human wastes, except one spring which may be contaminated with animal wastes. NeitherSalmonella norShigella were detected in any of the spring waters. It is concluded that the spring waters studied are unsuitable for human consumption unless disinfected.Dr Abdulrahman O. Musaiger is the senior author, to whom correspondence should be addressed. He is Head of the Nutrition Unit at the Bahrain Public Health Directorate. Mr Zakaria A. Khunji is a qualified microbiologist and the nutritionist at the Unit. Mr Hussain A. Mohana is a graduate and technician in charge of the food and water microbiology section at the Public Health Laboratory, Ministry of Health, Bahrain.