FTIR and XRD studies on some archaeological artifacts from Bohn, India

          Spectroscopic studies have been performed on archaeological pottery samples from Bhon in Maharashtra. The clay mineral type and its structural deformation due to firing have been studied from their Fourier Transform Infrared (FTIR) spectra. The maximum firing temperature attained during baking, firing conditions (open/reduced atmosphere) and iron mineral phase changes are well established. X-ray diffraction (XRD) studies on archaeological artifacts pave the way to identify the minerals

Efficient removal of nanoplastics from synthetic wastewater using electrocoagulation

Nanoplastics are emerging contaminants that have now transformed into a worldwide environmental concern. It is a lesser-known fact that several emerging contaminants, such as bisphenol and perfluoro alkylates adsorbing on micro and nanoplastics, could invade the food chain and cause irreversible damage to human health and the environment. Even though wastewater treatment plants (WWTPs) have been around for a long time, their removal strategy needs to be improved since this is one of the main routes that micro and nanoplastics get into the environment. UV deterioration, mechanical stresses, and biological processes cause plastics to break apart and turn into smaller pieces. They get small enough to be called nanoplastics, i.e. 1 um. We studied the removal of nanoplastics from synthetic wastewater using an electrocoagulation process. We used the polystyrene nanoparticles as nanoplastics synthesized from the expanded polystyrene waste (EPS). For studies on electrocoagulation (EC), aluminium electrodes were used in parallel combination at low voltage conditions. We take advantage of the release of gas bubbles from the process to enable the removal from the top by scraping them off. We studied the influence of various process parameters on removing nanoplastics, such as electrode spacing, salt concentration, and applied voltage. We found that a maximum removal efficiency of more than 95% could be achieved at a specific electrolyte concentration and pH of 7.2 +/- 0.3, illustrating that EC is a successful technique for removing nanoplastic pollutants from the aquatic environment. The advantage of the proposed method is that when nanoplastics and coagulants are mixed, they help make a foamy layer on top of the reactor that can be easily scraped off. The results of this study could serve as baseline information for achieving massive nanoplastics cleanup on a larger scale in an eco-friendly way.Comment: 26 pages, 8 figure

Unique Locomotive Wheelchair Robot Mechanism using Gesture and Android

Wheelchairs are used by the people who cannot walk due to physical illness, injury or other disability. Elderly peoples are unable to walk, we need to take care of these peoples every days .so, elderly people to maneuver a mechanical wheelchair, which many of them normally use for locomotion. Hence there is a need for designing a wheelchair that is intelligent and provides easy transportation for the physically challenged peoples and elderly peoples. In this context, an attempt has been made to propose a thought controlled wheelchair, which uses the captured signals from the user’s action and processes it to control the wheelchair. The signals which are captured and translated into movement commands by the microcontroller which in turn move the wheelchair

Protecting the protector: Laws regarding wetlands in Malaysia

Wetlands such as coastal mangroves take up the least amount of space compared to other types of forest areas in Malaysia, and yet, percentage wise, they face the greatest destruction. Their value as storehouses of biological diversity, breeding grounds for marine life and water purifier, is oft overlooked for the sake of economic "development" . The recent Tsunami disaster drove home another importance of coastal mangroves which has been sadly ignored and that is as a buffer between large waves and the coast. It was acknowledged by the Malaysian Prime Minister that the lack of mangroves due to their destruction for "development" purposes exacerbated the problem in Malaysia, particularly the island of Penang. This paper shall examine the laws in Malaysia that can be used to protect our mangroves in a critical light. It shall then proceed to make suggestions for change to ensure that such a precious resource is not lost

Simultaneous removal of natural organic matter and micro-organic pollutants from reverse osmosis concentrate using granular activated carbon

© 2019 Elsevier Ltd Although reverse osmosis produces high quality reusable water from wastewater the rejected concentrate (ROC) poses potentially serious health hazards to non-target species. This is especially the case when it is disposed into aquatic environments due to the presence of high concentrations of dissolved natural organics, micro-organic pollutants (MOPs) and other pollutants. In batch and column studies we found that granular activated carbon (GAC) was very effective in simultaneously removing dissolved organic carbon (DOC) and 18 MOPs from ROC. The amounts of all DOC fractions adsorbed (0.01–3 mg/g) were much higher than those of the MOPs (0.01–2.5 μg/g) mainly because ROC contained larger concentrations of DOC fractions than MOPs. However, the partition coefficient which is a measure of the adsorbability was higher for most of the MOPs (0.21–21.6 L/g) than for the DOC fractions (0.01–0.45 L/g). The amount of DOC fraction adsorbed was in the order: humics > low molecular weights > building blocks > biopolymers (following mostly their concentrations in ROC). The partition coefficient was in the order: low molecular weigth nuetrals > humics > building blocks > biopolymers. The MOPs were classified into four groups based on their hydrophobicity (log Kow) and charge. The four positively charged MOPs with high hydrophobicity had the highest amounts adsorbed and partition coefficient, with 95–100% removal in the GAC column. The MOPs that are negatively charged, regardless of their hydrophobicity, had the lowest amounts adsorbed and partition coefficient with 73–94% removal

Removal of organic matter from wastewater reverse osmosis concentrate using granular activated carbon and anion exchange resin adsorbent columns in sequence.

Reverse osmosis concentrate (ROC) generated as a waste stream during reverse osmosis treatment of reclaimed wastewater, presents significant disposal challenges. This is because it causes environmental pollution when it is disposed to lands and natural water bodies. A long-term dynamic adsorption experiment was conducted by passing ROC from a wastewater reclamation plant, firstly through a granular activated carbon (GAC) column, and subsequently through an anion exchange resin (Purolite) column, for the removal of two major ROC pollutants, namely dissolved organic carbon (DOC) and microorganic pollutants (MOP). GAC removed most of the smaller-sized low molecular weight neutrals and building block fractions as well as the hydrophobic fraction of DOC with much less removal by the subsequent Purolite column. In contrast, the humics fraction was less well removed by the GAC column; however, Purolite column removed all that was remaining of this fraction. This study demonstrated that combining adsorbents having different affinities towards a variety of DOC fractions constitute an effective method of taking advantage of their different properties and achieving larger DOC removals. Almost 100% of all 17 MOPs were removed by the GAC column, even after 2880 bed volumes of continuous use. This contrasted with the DOC fractions' removal which was much lower

Rate Equation Theory for Organic Diode Laser and Experimental Validation with Microcavity OLED

We present a new model for an organic laser diode based on rate equations for polarons, singlet and triplet excitons, both in host and dopant molecules, and photon densities. The model is validated by comparing calculated optical responses with measurements on high-speed low-Q OLEDS under pulsed nanosecond electrical excitation. The model confirms the threshold-current density of ~500A/cm2 observed in the recent first experiment with indication of lasing in an OLED with DFB-grating in the group of Adachi [1], if the Q-factor ~20K and no residual absorption occurs