Experimental Investigation of Diesel Engine Performance, Combustion and Emissions Using a Novel Series of Dioctyl Phthalate (DOP) Biofuels Derived from Microalgae

Physico-chemical properties of microalgae biodiesel depend on the microalgae species and oil extraction method. Dioctyl phthalate (DOP) is a clear, colourless and viscous liquid as a plasticizer. It is used in the processing of polyvinyl chloride (PVC) resin and polymers. A new potential biofuel, hydrothermally liquefied microalgae bio-oil can contain nearly 11% (by mass) of DOP. This study investigated the feasibility of using up to 20% DOP blended in 80% diesel fuel (v/v) in an existing diesel engine, and assessed the performance and exhaust emissions. Despite reasonable differences in density, viscosity, surface tension, and boiling point, blends of DOP and diesel fuel were found to be entirely miscible and no separation was observed at any stage during prolonged miscibility tests. The engine test study found a slight decrease in peak cylinder pressure, brake, and indicated mean effective pressure, indicated power, brake power, and indicated and brake thermal efficiency with DOP blended fuels, where the specific fuel consumption increased. This is due to the presence of 16.4% oxygen in neat DOP, responsible for the relatively lower heating value, compared to that of diesel. The emission tests revealed a slight increase in nitrogen oxides (NOx) and carbon monoxide (CO) emissions from DOP blended fuels. However, particulate matter (PM) emissions were lower from DOP blended fuels, although some inconsistency in particle number (PN) was present among different engine loads

Particulate number emissions during cold-start with diesel and biofuels: A special focus on particle size distribution

The share of biofuels in the transportation sector is increasing. Previous studies revealed that the use of biofuels decreases the size of particles (which is linked to an increase in particulate toxicity). Current emission regulations do not consider small particles (sub-23 nm); however, there is a focus in future emissions regulations on small particles. These and the fact that within cold-start emissions are higher than during the warmed-up operation highlight the importance of a research that studies particulate matter emissions during cold-start. This research investigates the influence of biofuel on PN and PM concentration, size distribution, median diameter and cumulative share at different size ranges (including sub-23 nm and nucleation mode) during cold-start and warm-up operations using diesel and 10, 15 and 20% mixture (coconut biofuel blended with diesel). During cold-start, between 19 and 29% of total PN and less than 0.8% of total PM were related to the nucleation mode (sub-50 nm). Out of that, the share of sub-23 nm was up to 9% for PN while less than 0.02% for PM. By using biofuel, PN increased between 27 and 57% at cold-start; while, the increase was between 4 and 19% during hot-operation. The median diameter also decreased at cold-start and the nucleation mode particles (including sub-23 nm particles) significantly increased. This is an important observation because using biofuel can have a more adverse impact within cold-start period which is inevitable in most vehicles’ daily driving schedules.<br/

Performance implications of export assistance: the mediating role of export entrepreneurship

Purpose Although both institutional export assistance and entrepreneurial orientation (EO) contribute separately and positively to export performance, the interplay between them has received little attention. This study examines the role of international EO in deriving performance benefits from governmental and nongovernmental export assistance. Design/methodology/approach In this longitudinal study, two surveys were administered at two different times: In 2011, 705 Bangladeshi apparel exporters were surveyed, and in 2019, a subsequent survey of 198 firms in multiple industries was conducted. The aim of the surveys was to assess the relationships between governmental and nongovernmental assistance, EO and export performance. Findings The results of the first survey show that, while nongovernmental assistance influences performance directly and via EO, governmental assistance has only direct effects. Furthermore, the negative influence of government assistance on EO reduces the total effects and renders them nonsignificant. The results of the second survey demonstrate that government EPPs have both direct and indirect positive and significant effects on market performance, indicating a partial mediation, whereas quasi-governmental assistance has positive and significant direct effects as well as negative but nonsignificant indirect effects. Nongovernmental EPPs have both direct and indirect significant effects on international performance, indicating a partial mediation. Research limitations/implications The study has important implications for researchers studying export assistance and its impact on firm performance. Instead of adopting a parochial view of government assistance, this study categorizes such assistance into three types – government, quasi-government and nongovernment. Furthermore, this study bridges the export assistance and international entrepreneurship literature by including EO. Practical implications Entrepreneurs must emphasize the use of government assistance in order to enhance export performance. However, to promote both entrepreneurship and performance, they must emphasize nongovernment assistance. Exporters should also capitalize on the assistance extended by various quasi-governmental agencies to bolster export performance. Originality/value Given the performance advantage of export assistance, this study highlights the contribution of the private sector in promoting export entrepreneurship while shedding light on the pernicious role of (quasi-)governmental assistance in export entrepreneurship

Focal Liver Lesion Detection in Ultrasound Image Using Deep Feature Fusions and Super Resolution

This research presents a machine vision approach to detect lesions in liver ultrasound as well as resolving some issues in ultrasound such as artifacts, speckle noise, and blurring effect. The anisotropic diffusion is modified using the edge preservation conditions which found better than traditional ones in quantitative evolution. To dig for more potential information, a learnable super-resolution (SR) is embedded into the deep CNN. The feature is fused using Gabor Wavelet Transform (GWT) and Local Binary Pattern (LBP) with a pre-trained deep CNN model. Moreover, we propose a Bayes rule-based informative patch selection approach to reduce the processing time with the selective image patches and design an algorithm to mark the lesion region from identified ultrasound image patches. To train this model, standard data ensures promising resolution. The testing phase considers generalized data with a varying resolution and test the performance of the model. Exploring cross-validation, it finds that a 5-fold strategy can successfully eradicate the overfitting problem. Experiment data are collected using 298 consecutive ultrasounds comprising 15,296 image patches. This proposed feature fusion technique confirms satisfactory performance compared to the current relevant works with an accuracy of 98.40%

Widespread production of bioenergy: land and water availability factors

Widespread production of bioenergy appears to be a potential candidate to counteract fossil fuel depletion and environmental degradation challenges. However, the competing role of bioenergy with food and feed in the use of land and water resources intrinsically causes numerous social and environmental challenges, which translate into sustainability factors for bioenergy. This paper evaluates the status and prospects of land and water resources in terms of sustainability factors concerning widespread production of bioenergy. Four major factors that broadly connect with sustainability of bioenergy are evaluated in this work: land availability, soil erosion, nutrients and biodiversity losses, and water availability. This work has found that although widespread production of bioenergy is subject to several limitations and constraints associated with land and water resources, these two resources are still sufficient at the global level. Globally, available land for biomass production is expected to remain within the range of 1.17 to 2.18 Gha by 2050, which will not compete with food and feed production. Recognising the limits of using land and water resources against regional disparity and competing applications, as well as employing rational practices, could enable the attainment of extensive production of bioenergy

Utilizing Gravitational Energy as an Alternative Source To Produce Usable Electricity

Gravity is one of the most available and cheap source of energy. Utilization of gravity is being done from ancient times. But utilizing it as a source of electricity is not much old concept. Gravity light is an example of gravitational energy conversion to electrical energy. Using gravity as the main energy source a simple lever mechanism that would provide torque which will be rotating a generator via fly wheel. While moving, the vehicles possessing some kinetic energy that is wasted. This kinetic energy can be utilized on the lever mechanism to lift up the weight and in turn the generator can be rotated via fly wheel. This paper presents a comprehensive review on harvesting electrical energy using gravity as the main source. From this study, one is able to gain an idea about energy harvesting from gravity, its use in a road highway for energy production, an estimate of the cost of such setups and a possible means of putting together such a contraption