Search results for "Exchange"

Carbohydrate and nutritional responses to stem girdling and drought stress with respect to understanding symptoms of Huanglongbing (HLB) in Citrus

2013

The most important worldwide problem in citrus production is the bacterial disease Huanglongbing (HLB; citrus greening) caused by phloem-limited bacterium Candidatus Liberibacter asiaticus. The earliest visible symptoms of HLB on leaves are vein yellowing and an asymmetrical chlorosis referred to as “blotchy mottle”, thought to be the result of starch accumulation. We tested the hypothesis that such visible symptoms are not unique to HLB by stem girdling 2-yr-old seedlings of two citrus rootstocks with and without drought stress in the greenhouse. After 31 d, girdling had little effect on shoot growth but girdling increased the relative growth rate of shoots in drought stressed trees. Starc…

Possible role of mannitol as an oxygen radical scavenger in olive

2011

Along with mannose and sucrose, olive produces large amounts of mannitol in photosynthesizing leaves. Leaf mannitol shows large variation among olive genotypes and Sicilian cultivars with different leaf mannitol content were used in our trials to see whether mannitol may function as an additional non-enzymatic system to protect cells from oxygen radicals and photosystem damage. In one experiment, entire shoots of 'Passulunara', 'Castriciana', 'Nocellara del Belice', and 'Moresca' olive trees were taken to a greenhouse, and mature leaves were treated with paraquat solution, which generates oxygen radicals in presence of light. After 48 hours leaves were sampled, photographed and percent of n…

Impact of COVID-19 on aquaculture sector in Malaysia: Findings from the first national survey

2021

Abstract Malaysian aquaculture sector consists of 391,000 t of cultivated organisms produced per year with an economic value for over USD 700 million as estimated in 2019. The COVID-19 pandemic caused a large global human pandemic and it is currently ongoing, affecting profoundly Malaysian aquaculture, which is vital for seafood provision and security assurance. Thus, to increase our understanding about how the pandemic affects aquaculture sectors is crucial to design possible management measures both at local and national level. To do it, we designed a survey, starting in May 2020, consisting of 25 online questions to collect information about the impact of COVID-19 on the aquaculture sect…

Valuing the unmarketable: an ecological approach to the externalities estimate in fishing activities

2013

In a rapidly changing world, sustainability, if it can be said to exist at all, is concept that has attained mythic status, often pursued and rarely reached. In order to improve our capability to cope with environmental problems, adopting an Ecosystem Approach has been suggested. One of the major challenges in the implementation of this new paradigm relates to control of externalities. The recognition and quantification of externalities is often cast as valuing the unmarketable, and there are several approaches that have been proposed. Here, we analyze the opportunity to “feed” the economic valuation with ecological concepts. From an ecological perspective, the energy required to sustain a …

Modelling within-canopy heat exchanges of green roofing

2013

Experimental results on a solar desiccant and evaporative cooling system equipped with wet heat exchangers

2012

An innovative solar assisted desiccant and evaporative cooling (DEC) system for building air conditioning has been installed at the Solar Laboratory of the University of Palermo. In this system, air-to-air packaged wet heat exchangers are used to maximise the exploitation of the evaporative cooling potential associated with the exhaust air stream. Results obtained are very positive, showing that DEC systems can benefit from the use of wet heat exchangers to efficiently cool the air stream after the adsorption process in the desiccant wheel, without any change in moisture content

Economical aspects, toxicity, and environmental fate of cerium oxide

2020

Abstract The present chapter reports some economical aspects of the cerium oxide market. Porter’s and PESTEL analyses have been used to evidence the strengths and weaknesses of the ceria market, along with the potentiality and opportunities within the years to come. The wide use of CeO2 nanoparticles in many applications requires to consider also issues related to their toxicity and environmental fate. In this regard, some contradictory reports in the relevant literature have been surveyed, thus highlighting the need for further and detailed investigation on these topics in order to propose effective strategies of risk assessment and environmental remediation.

Ion Exchange Membrane deformation and its relevance in Reverse ElectroDialysis

2017

Reverse electrodialysis (RED) is an innovative electro-membrane technology for electric energy generation from two salt solutions with different concentration. This different concentration is the driving force to a selective movement of ions from the concentrate channel to the dilute one oriented by Ion Exchange Membranes (IEMs). Typically, RED stack are made by piling alternatively cation exchange membranes and anion exchange membranes with the aid of spacers or profiles built on the membrane surface. Two electrodic compartments are placed at the two ends of the stack, where the ion flux generated is converted into an electric current able to circulate through an external load connected to…

Electrodialysis with bipolar membranes for the generation of NaOH and HCl solutions from brines: an inter-laboratory evaluation of thin and ultrathin…

2022

The SEArcularMINE project aims to recover critical raw materials (CRMs) from brines from saltworks, thus facing a CRM shortage within Europe. To promote a fully circular scheme, the project valorises concentrated brines using electrodialysis with bipolar membranes (EDBM) to generate the required amounts of reactants (i.e., acids and bases). Regarding the performances of new non-woven cloth ion-exchange membranes (Suez): (i) an ultra-thin non-woven polyester cloth and (ii) a thin polypropylene cloth acting as the support structures were assessed. Additionally, the anion layer includes a catalyst to promote the water dissociation reaction. The effect of current density (100, 200, and 300 A m&…

Techno-economic assessment of multi-effect distillation process for the treatment and recycling of ion exchange resin spent brines

2019

Abstract A treatment chain including nanofiltration, crystallization and multi-effect distillation (MED) is for the first time proposed for the treatment of an effluent produced during the regeneration of Ion Exchange resins employed for water softening. The goal is to recover the minerals and to restore the regenerant solution to be reused in the next regeneration cycle. MED is the most crucial unit of the treatment chain from an economic point of view. A techno-economic analysis on the MED unit was performed and a novel performance indicator, named Levelized Brine Cost, was introduced as a measure of the economic feasibility of the process. Different scenarios were analysed, assuming diff…