Experimental investigation on the effect of liquid phase and vapor phase separation over performance of falling film evaporator

Energy, cost, and environmental concerns play a vital role in understanding governing parameters of distributor design in falling film evaporators. Distributor design is a hidden parameter in many experimental papers. The uniform distribution of liquid refrigerant over the tube bundle mostly depends on two-phase liquid refrigerant and vapor refrigerant. This work conducted experiments with two distribution systems with and without separation of liquid-vapor refrigerant after expansion valve for the same evaporator capacity with R134a as a refrigerant. Results reveal that; separating vapor refrigerant has a positive impact on the approach of the evaporator with an open system distributor arrangement. The highest delta T and lowest practice are found at a heat flux of 13.97 kW/m² with an available system distributor compared to a closed system with a heat flux of 14.25 kW/m². The open system arrangement in the distributor is the novel parameter for distributor design, ensuring uniform distribution with minimum pressure drop and dry suction. An open system distributor has an average 16.1% capacity increase over a closed system. The experimental analysis helps to understand different parameters for the design of distributors in falling film evaporators for uniform distribution.     

Analytical mapping of research on disaster management,types and role of ICT during 2011–2018

Catastrophic disasters like earthquake and flood cause widespread destruction and financial devastation. This has brought disaster management into limelight making it a burgeoning academic research field. The remarkable rise of ICT (Information and Communication Technology) has instigated the scientific world to incorporate these technologies in disaster management. This study presents scientometric analysis to identify the status quo of research on the management of various disasters and role of ICT in it. This paper uses bibliographic data retrieved from Scopus for the observation period from 2011 to 2018. We provide extensive insights into growth of publications, citation pattern and their connectedness with other subject disciplines. Furthermore, we identify most productive and influential countries, institutes and journals. Our study analyses co-occurrence of keywords using Visualization of Similarities (VOS) Viewer. This structured overview will enhance the understanding of this field leading to more focussed and purposeful research.     

Effect of pressure and temperature on the hydropyrolysis of cotton residue

With growing concerns of fossil fuel resources availability and the volatility of crude oil price, it is becoming imperative day by day to utilize the renewable sources of energy in a sustainable, environment friendly and energy efficient manner. India is the world’s second largest producer of cotton after China. India also has several agricultural and forest residues, and cotton residue is one of the most abundant agricultural residues after rice and wheat residues. The hydropyrolysis of cotton residues has been carried out at various pressures (1, 20 and 40 bar) and temperatures (300, 350, 400 and 450 °C). The effects of temperature and pressure have been studied to understand their yield patterns, and it has been observed that 20 bar pressure and 400 °C are the optimum conditions. The thermogravimetric analysis shows that cotton residue has two significant decomposition temperatures. The SEM, XRD patterns and FT-IR spectra clearly indicate the decomposition of the macromolecular structure of the cotton residue and formation of low molecular weight hydrocarbons suitable for various applications.     

Connecting the dots: mapping habitat connectivity for tigers in central India

Large connected landscapes are paramount to maintain top predator populations. Across their range, tiger (Panthera tigris) populations occur in small fragmented patches of habitat, often isolated by large distances in human-dominated landscapes. We assessed connectivity between 16 protected areas (PAs) in central India, a global priority landscape for tiger conservation, using data on land use and land cover, human population density, and transportation infrastructure. We identified and prioritized movement routes using a combination of least-cost corridor modeling and circuit theory. Our analyses suggest that there are several opportunities to maintain connectivity in this landscape. We mapped a total of thirty-five linkages in the region and calculated metrics to estimate their quality and importance. The highest quality linkages as measured by the ratio of cost-weighted distance to Euclidean distance are Kanha–Phen/Bandhavgarh–SanjayGhasidas/Melghat–Satpura, and cost-weighted distance to least-cost path length are Nawegaon–Tadoba/Achanakmar–SanjayGhasidas/Kanha–Phen. We used current flow centrality to evaluate the contribution of each PA and linkage toward facilitating animal movement. Values are highest for Kanha and Pench tiger reserves, and the linkages between Kanha–Phen, Kanha–Pench, and Pench–Satpura, suggesting that these PAs and linkages play a critical role in maintaining connectivity in central India. In addition, smaller areas such as Bor, Nawegaon, and Phen have high centrality scores relative to their areas and thus may act as important stepping stones. We mapped pinch points, which are sections of the linkages where tiger movement is restricted due to unfavorable habitat, transportation networks, human habitation, or a combination of factors. Currently, very limited data exist on tiger movement outside of PAs to validate model results. Regional-scale connectivity mapping efforts can assist managers and policy makers to develop strategic plans for balancing wildlife conservation and other land uses in the landscape.     

Constitutive model for municipal solid waste incorporating mechanical creep and biodegradation-induced compression

A constitutive model is proposed to describe the stress–strain behavior of municipal solid waste (MSW) under loading using the critical state soil mechanics framework. The modified cam clay model is extended to incorporate the effects of mechanical creep and time dependent biodegradation to calculate total compression under loading. Model parameters are evaluated based on one-dimensional compression and triaxial consolidated undrained test series conducted on three types of MSW: (a) fresh MSW obtained from working phase of a landfill, (b) landfilled waste retrieved from a landfill after 1.5 years of degradation, and (c) synthetic MSW with controlled composition. The model captures the stress–strain and pore water pressure response of these three types of MSW adequately. The model is useful for assessing the deformation and stability of landfills and any post-closure development structures located on landfills.     

Case Studies on Biological Treatment of Tannery Effluents in India

Abstract

This paper presents a comparative assessment of the cost and quality of treatment of tannery wastewater in India by two common effluent treatment plants (CETPs) constructed for two tannery clusters, at Jajmau (Kanpur) and at Unnao in the state of Uttar Pradesh, India. The Jajmau plant is upflow anaerobic sludge blanket (UASB) process-based, while the Unnao plant is activated sludge process (ASP)-based. Investigations indicated that the ASP-based plant was superior in all respects. Total annualized costs, including capital and operation and maintenance costs, for the UASB and ASP plants were Rs. 4.24 million/million liters per day (MLD) and Rs. 3.36 million/MLD, respectively. Land requirements for the two CETPs were 1.4 hectares/MLD and 0.95 hectares/MLD, respectively. Moreover, the treated UASB effluent had higher biochemical and chemical oxygen demand (BOD/COD) and considerable amounts of other undesirable constituents, like chromium (Cr) and sulfide, as compared with the ASP effluent, which had lower BOD/COD and negligible concentration of sulfide and Cr. Sludge production from the UASB-based plant was also higher at 1.4 t/day/MLD, in comparison to the sludge production of 0.8 t/day/MLD for the ASP-based plant. Also, the entire sludge produced in the UASB-based plant was Cr-contaminated and, hence, hazardous, while only a small fraction of the sludge produced in the ASP-based plant was similarly contaminated. The results of this study are at variance with the conventional wisdom of the superiority of anaerobic processes for tannery waste-water treatment in tropical developing countries like India.     

Immunotoxic manifestations in rats following inhalative exposure to furfural vapors

Furfural is an industrial compound used as a process intermediate and as a solvent; it poses a potential inhalation hazard in occupational settings. This study was carried out to find furfural-induced immunotoxicity in Wistar rat following inhalative exposure. The weights of thymus and lymph node were found decreased, while the weights of the liver and the adrenal gland were significantly increased following furfural exposure. Delayed-type hypersensitivity response was found decreased in furfural vapors-exposed animals when compared to that of control animals. The phagocytic index of peritoneal and alveolar exudates showed significant decrease and was most prominent (90%) in 30 days-exposed groups. The number of anti-rat anti-sheep red blood cell immunoglobulin M plaque forming cells of spleen got decreased in furfural-exposed groups in comparison to control. Taken together, this study indicates that inhalation of furfural induces immunotoxic manifestations that could lead to severe immunological disorders.     

Arsenic-induced health crisis in peri-urban Moyna and Ardebok villages, West Bengal, India: an exposure assessment study

Drinking of arsenic (As)-contaminated groundwater has adverse effects on health of millions of people worldwide. This study aimed to determine the degree of severity of As exposure from drinking water in peri-urban Moyna and Ardebok villages, West Bengal, India. Arsenic concentrations in hair, nail and urine samp les of the individuals were determined. Arsenical dermatosis, keratosis and melanosis were investigated through medical evaluation. We have evaluated the association between As exposure from drinking water, and keratosis and melanosis outcomes. The results showed that 82.7?% of the sampled tube wells contain As concentrations above 10?μg/L, while 57.7?% contain As concentrations above 50?μg/L. The hair, nail and urine As concentrations were positively correlated with As concentrations in drinking water. In our study population, we observed a strong association between As concentrations ranging 51-99?μg/L and keratosis and melanosis outcomes, although the probability decreases at higher concentration ranges perhaps due to switching away from the use of As-contaminated tube wells for drinking and cooking purposes. High As concentrations in hair, nail and urine were observed to be associated with the age of the study population. The level of As concentrations in hair, nail and urine samples of the study population indicated the degree of severity of As exposure in the study region.     

Modulation of mutagenicity in Salmonella typhimurium and antioxidant properties and antiproliferative effects of fractions from Cassia fistula L. on human cervical HeLa and breast MCF-7 cancer cells

Environmental Science and Pollution Research - The present study investigated the antimutagenic, antioxidant, and antiproliferative properties of extracts of Cassia fistula prepared by sequentially...     

Role of UPP pathway in amelioration of diabetes-associated complications

Environmental Science and Pollution Research - Type 2 diabetes (T2D) is one of the most widely spread metabolic disorder also called as “life style” disease. Due to the alarming number...