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Achieving the goals of sustainable development and poverty reduction implies an important condition for access to electricity for the entire population. In the economic literature, the relationship between electricity consumption and economic growth has different perspectives. The lack of good governance within an economy, besides the deficiencies of energy resources, is a key issue in worsening energy issues for developing countries. These countries have failed to alleviate the energy crises that have hindered development prospects, amid flourishing corruption and inefficient governments. Our research, using a panel methodology, analyzes the long-term relationship between energy consumption, economic growth and good governance for 14 Central and Eastern European countries, over the period 1995–2017. The study demonstrates empirically that there is a causal relationship between electricity consumption and economic growth, underlining the fact that deficiencies in the energy system lead to slowing economic growth. The study also shows that good governance influences electricity and Gross Domestic Product (GDP) consumption, and the governments from Central and Eastern European countries have to restore good governance in the economy, creating an environment conducive to investment in the energy sector, which would increase competition and reduce inefficiencies in the production, transmission, and distribution of energy.

The pretreatment of lignocellulosic biomass (LC biomass) prior to the anaerobic digestion (AD) process is a mandatory step to improve feedstock biodegradability and biogas production. An important potential is provided by lignocellulosic materials since lignocellulose represents a major source for biogas production, thus contributing to the environmental sustainability. The main limitation of LC biomass for use is its resistant structure. Lately, biological pretreatment (BP) gained popularity because they are eco-friendly methods that do not require chemical or energy input. A large number of bacteria and fungi possess great ability to convert high molecular weight compounds from the substrate into lower mass compounds due to the synthesis of microbial extracellular enzymes. Microbial strains isolated from various sources are used singly or in combination to break down the recalcitrant polymeric structures and thus increase biogasgeneration. Enzymatic treatment of LC biomass depends mainly on enzymes like hemicellulases and cellulases generated by microorganisms. The articles main purpose is to provide an overview regarding the enzymatic/biological pretreatment as one of the most potent techniques for enhancing biogas production.

In order to obtain bioenergy (biogas, biofuel) or pellets, different types of lignocellulosic biomass are subjected to a mechanical pretreatment, first by size reduction, then by separating, and ultimately by fracturing or bio-refining. Biomass processing mainly refers to a grinding process that occurs until reaching certain limits. The size reduction process, such as grinding, is an operation that is executed with different levels of energy consumption, considering biomass mechanical characteristics and the necessary grinding level. This paper, illustrates a comparative analysis of experimental results obtained by grinding multiple types of vegetal biomass (Miscanthus, corn stalks, alfalfa, willow) used in the process of bio-refining and bio-fracturing. Experiments were realized using both a laboratory knife mill Grindomix GM200 (Retsch GmbH, Haan, Germany), and a 22 kW articulated hammer mill, using different grinding system speeds and different hammer mill sieves. Results have shown that biomass mechanical pre-processing grinding leads to supplementary costs in the overall process through bio-refining or bio-fracturing in order to obtain bio-products or bio-energy. So, specific energy consumption for grinding using a hammer mill can reach 50–65 kJ/kg for harvested Miscanthus biomass, and 35–50 kJ/kg for dried energetic willow, using a 10 mm orifice sieve, values which increase processing costs.

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The purpose of this study was to analyze fiscal behavior in the European Union countries, to highlight the implications of institutional constraints on healthy fiscal attitudes, and to test the relationship between government decisions, fiscal responsibility instruments, and the sustainability of public finances during the period 2000–2014. By using panel data analysis, we tested the responsiveness of primary balance to government indebtedness, as well as to some determinants of fiscal responsibility, such as the degree of public spending or fiscal rules effectiveness, and we included two different perspectives regarding fiscal rules status. First, we computed a fiscal responsibility index, which measures the applicability of or compliance with the fiscal rules, referring to legal dimensions and administrative and institutional capacity. Second, we established a fiscal responsibility convergence index, which measures the status of the EU Member States regarding the approach of numerical rules. The empirical findings indicate that fiscal authorities do not act to the existing stock of public debt and highlights a negative response of budget balances to the stock of outstanding debt. Fiscal position improves when the index of fiscal responsibility is involved and countries become more sustainable when they are related to the entire level of fiscal governance, with respect to legal framework, institutional and administrative capacity, but at the debt ratio threshold of over 90%, the effect of the overall fiscal rule comes out as less relevant for the improvement of the primary balance.

The aim of this article is to present a nonconventional method for the efficient removal of lead ions from industrial wastewater. For this purpose, magnetite nanomaterial was used, which was very easily separated from the wastewater at the end of the treatment due to its magnetic properties. Currently, nanotechnology is an efficient and inexpensive manner that is being researched for wastewater treatment. Additionally, iron oxide nanoparticles are widely used to remove heavy metal ions from water due to their special properties. The experimental results detailed in this article show the influence of pH and contact time on the process of adsorption of lead ions from wastewater. The magnetite nanomaterial had its maximum efficiency of speed when the wastewater had pH 6. At a lower pH, the highest treatment efficiency was over 85%, and the required contact time has doubled. When the pH increases above 6, the precipitation process occurs. Langmuir and Freundlich models were used to describe the adsorption process.

The accumulation of waste and toxic compounds has become increasingly harmful to the environment and human health. In this context, the use of laccases has become a focus of interest, due to the properties of these versatile enzymes: low substrate specificity, and water formation as a non-toxic end product. Thus, we begin our study with a general overview of the importance of laccase for the environment and industry, starting with the sources of laccases (plant, bacterial and fungal laccases), the structure and mechanism of laccases, microbial biosynthesis, and the immobilization of laccases. Then, we continue with an overview of agro-waste treatment by laccases wherein we observe the importance of laccases for the biodisponibilization of substrates and the biodegradation of agro-industrial byproducts; we then show some aspects regarding the degradation of xenobiotic compounds, dyes, and pharmaceutical products. The objective of this research is to emphasize and fully investigate the effects of laccase action on the decomposition of lignocellulosic materials and on the removal of harmful compounds from soil and water, in order to provide a sustainable solution to reducing environmental pollution.