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In this paper, perlite mining and rice production by-products, namely run-of-mine perlite and rice husk ash, are used as fine aggregates in combination with pumice and calcareous aggregates to produce lightweight concrete. Their use is evaluated mainly in terms of the durability of the concrete, by comparing four optimized lightweight concrete mixtures of similar density and strength with a reference one of normal weight. The sorptivity due to capillary sorption, open porosity, chloride migration, penetration resistance, and freeze and thaw response were studied to evaluate the durability of the lightweight concrete. According to the experimental results, the examined mixtures developed an adequate strength in order to be classified into strength classes greater than LC25/28 and, therefore, be used in structural applications. The durability of the mixtures was also sufficient, especially as far as the chlorides’ penetration resistance is concerned, which was found to be up to 39% lower compared to the reference mixture. The sorptivity and open porosity of the LWC mixtures increased due to the porous nature of the lightweight aggregates, and the mixtures were also found to be susceptible to freeze and thaw cycles. Exceptionally, the lightweight concrete mixtures comprising pumice and perlite exhibited a lower sorptivity and resistance to chloride penetration than the standard concrete and a promising tolerance to freezing and thawing. Thus, the optimized combination of pumice and perlite is a sustainable recommendation for structural lightweight concrete production and use, promoting the wider exploitation of natural aggregates with an acceptable compromise on strength and durability.

Type-B Aortic Dissection is a cardiovascular disease in which a tear develops in the intimal layer of the descending aorta, allowing pressurized blood to delaminate the layers of the vessel wall. In medically managed patients, long-term aneurysmal dilatation of the false lumen (FL) is considered virtually inevitable and is associated with poorer disease outcomes. While the pathophysiological mechanisms driving FL dilatation are not yet understood, hemodynamic factors are believed to play a key role. Computational Fluid Dynamics (CFD) and 4D-Flow MRI (4DMR) analyses have revealed correlations between flow helicity, oscillatory wall shear stress, and aneurysmal dilatation of the FL. In this study, we compare CFD simulations using a patient-specific, three-dimensional, three-component inlet velocity profile (3D IVP) extracted from 4DMR data against simulations with flow rate-matched uniform and axial velocity profiles that remain widely used in the absence of 4DMR. We also evaluate the influence of measurement errors in 4DMR data by scaling the 3D IVP to the degree of imaging error detected in prior studies. We observe that oscillatory shear and helicity are highly sensitive to inlet velocity distribution and flow volume throughout the FL and conclude that the choice of IVP may greatly affect the future clinical value of simulations.

Open Innovation has great significance and so far several definitions have been proposed, the most widely accepted definition referring to the correlation of Open Innovation with research organizations. Helix models have been proposed to analyze how collaborations work among key stakeholders and research centers and they were found to have a prominent part in all their iterations. This work presents the challenges that research organizations face in terms of interaction with other organizations, their operations (resources, funding issues), and how they determine the research directions to be followed, and analyzes how the adoption of Open Innovation practices can tackle these challenges and the effects it has. The Open Innovation practices of outsourcing and co-creation are mentioned, with the latter needing to be further developed and elaborated. We propose a novel process, called Research Loop, which aims and succeeds to provide Open Innovation for research organizations. It achieves to involve several different organizations, identify existing research gaps, and produce new knowledge. The proposed process includes the various advantages of applying Open Innovation to the analyzed research centers.

The paper deals with the assessment of CO2 storage capacity in cement concrete using reactive transport modelling of the accelerated carbonation, i.e. 15 Vol % and experiments. To meet the most rea...

A novel methodology for analyzing hybrid wind turbine-photovoltaic off-grid systems with battery storage is presented in this work. To support off-grid operation, small settlements were chosen as case studies for these autonomous hybrid systems. Μeteorological, demographic, geographical, geospatial, land use and load data with the design and implementation of off-grid power plants were used. The study aims at further supporting and improving off-grid hybrid energy systems in terms of design, analysis and integration, while a life-cycle analysis for the proposed systems was performed to quantify the relative environmental impact, as well. The findings show that the implementation of autonomous energy production by renewable energy systems for off-grid small settlements, based on the presented methodology, is feasible.

The Kármán–Howarth–Monin–Hill equation is employed to study the production and interscale energy transfer in a boundary layer undergoing bypass transition due to free-stream turbulence. The energy flux between different length scales is calculated at several streamwise locations covering the laminar, transitional and turbulent regimes. Maps of scale energy production and flux vectors are visualised on two-dimensional planes and three-dimensional hyper-planes that comprise both physical and separation spaces. In the transitional region, the maps show strong inverse cascade in the streamwise direction near the wall. The energy flux vectors emanate from a region of strong production and transfer energy to larger streamwise scales. To provide deeper insight into the origin of the inverse cascade process, we decompose the energy flux vector into components arising from nonlinear interactions between velocity fluctuations, mean flow inhomogeneity, pressure and viscous effects. The inverse cascade is mainly due to the nonlinear interaction component, and in the earliest stages of transition this component competes with that due to mean flow inhomogeneity. By superposing the instantaneous velocity fields and the energy flux vectors, we relate the inverse cascade process to the growth of turbulent spots. Once the transition process is complete, the maps become very similar to those observed in other fully developed turbulent flows, such as channel flow. Finally we characterise the nonlinear interaction term using probability density functions (PDFs) evaluated at different wall-normal heights. The PDFs are asymmetric and wide-skirted as in homogeneous isotropic turbulence, but are skewed towards positive values reflecting the inverse cascade.

Efficient and harmless disposal of landfill leachate has attracted increasing attention. In this study, the bio-electro-Fenton method was investigated and developed to degrade the organic compounds in landfill leachate by hydroxyl radical oxidation. The optimal operational parameters (i.e., pH and external voltage) of the bio-electro-Fenton system were detected. Under the conditions of pH 2, 0.6 V, the highest total chemical oxygen demand (COD) decrement efficiency was obtained (about 70%), with apparent removal constant at 6 h (k

Experimental investigation and model simulation was combined to identify the effect of metal ions on mitigating ammonia inhibition during anaerobic digestion. Five metal ions (Ca, Mg, Cu, Zn, Fe) were tested in reactors with 1 g-glucose/L/d and 5 g-N/L under fed batch operation. Ca addition was considered the optimal approach with a 25% increment in methane production via balanced-strengthening dehydrogenases and reinforcing protein-binding structure. Gene-sequencing results suggested 50% and 15% increment in acetotrophic-related and hydrogenotrophic-related dehydrogenases, respectively, after Ca addition. The Anaerobic Digestion Model No.1 was modified by introducing lactate-related reactions, syntrophic acetate oxidation process, and kinetic equation of metal ions, with satisfactory predictions of methane and intermediates (R

We investigate the role of laminar/turbulent interface in the interscale energy transfer in a boundary layer undergoing bypass transition, with the aid of the Karman-Howarth-Monin-Hill (KHMH) equation. A local binary indicator function is used to detect the interface and employed subsequently to define two-point intermittencies. These are used to decompose the standard-averaged interscale and interspace energy fluxes into conditionally-averaged components. We find that the inverse cascade in the streamwise direction reported in an earlier work arises due to events across the downstream or upstream interfaces (head or tail respectively) of a turbulent spot. However, the three-dimensional energy flux maps reveal significant differences between these two regions: in the downstream interface, inverse cascade is stronger and dominant over a larger range of streamwise and spanwise separations. We explain this finding by considering a propagating spot of simplified shape as it crosses a fixed streamwise location. We derive also the conditionally-averaged KHMH equation, thus generalising similar equations for single-point statistics to two-point statistics. We compare the three-dimensional maps of the conditionally-averaged production and total energy flux within turbulent spots against the maps of standard-averaged quantities within the fully turbulent region. The results indicate remarkable dynamical similarities between turbulent spots and the fully turbulent region for two-point statistics. This has been known only for single-point quantities, and we show here that the similarity extends to two-point quantities as well.

Tidal energy can play an important role in the Net Zero transition. Increasing tidal turbine performance through innovation is crucial if the cost of tidal energy is to become competitive compared to other sources of energy. The present investigation is a proof-of-concept study for the application of Vortex Generators (VGs) on tidal turbines in view of increasing their performance. The more mature wind energy industry uses passive VGs either as a retrofit or in the blade design process to reduce separation at the inboard part of wind turbine blades. Tidal turbine blades also experience flow separation and here we examine whether passive vane VGs can be used to reduce or suppress that separated flow. First, a wind tunnel investigation is performed to assess the performance of VGs on a 20% thick profile from the blade. Then, the VG effect on the 2D-profile is modelled in a Reynolds Averaged Navier-Stokes in-house solver. Results show that low profile VGs, i.e. VGs shorter than the local boundary layer, can increase the performance of the blade profile and successfully reduce flow separation. The VG effect on blade performance is examined in model scale and in full-size. VGs successfully suppress separation in both cases and it is shown that full-size information should be used for the placement of VGs. A maximum power coefficient increase of 1.05% is observed at a tip speed ratio of λ=3. The present proof-of-concept study demonstrates for the first time the potential of passive VGs to be included either in the design process of a tidal turbine blade or as a retrofit solution.

The introduction of new regulations for Means of Access (MA) has led to an increase in the number and complexity of access openings, an increase in the size of the access openings in the ship’s structure, and a stricter maintenance regime which presents new challenges throughout the life of modern vessels. Several of the major issues at the design stage of Permanent Means of Access (PMA); the construction of ships; the application of protective coatings during new building, together with coating maintenance during the service lifetime; problems related to cleaning holds after cargoes have been removed; action by the Butterworth crude oil washing action and the challenges of maintenance in ballast tanks, are discussed in this paper.

Road traffic accidents are the most common cause of blunt native kidney injuries. Transplanted kidneys are more exposed to such injuries due to the common positioning in the iliac fossa compared with the relatively protected position of the native kidneys. The small number of cases identified in the literature describe grade II and III transplant kidney injuries that were treated surgically. In our case a grade IV injury was managed conservatively giving the necessary time to appropriately plan the future renal replacement therapy options for the patient.

Greece produces significant amounts of residual biomass due to its intense agricultural and agro-industrial sector. The anaerobic digestion process has been frequently considered as the best environmental and economic solution for energy recovery from different biodegradable waste such as agricultural waste, livestock manure, agro-industrial waste, as well as for their co-digestion. The aim of this study was the assessment of biochemical methane potential (BMP) of biomass feedstocks representative of Northern and Southern Greece, which are available during the fall/winter and spring/summer seasons, through the implementation of BMP assays. The raw residues evaluated in the current work included: (a) crop residues (corn silage and unsuitable for human consumption watermelon), (b) agro-industrial residues (malt, tomato processing residues, orange peels and olive pomace) and (c) livestock (cattle) manure. Tests of both single substrates and various mixtures were conducted for the evaluation of their methane yields. The results of the mono-substrates are in accordance with other studies in the literature, with watermelon presenting the highest methane potential (421.0 ± 3.4 ml CH

Supply chain is a crucial part of the world economy and everyday life. During the outbreak of COVID-19 in 2020, governments across the globe have tried to maintain the supply chain operations in most of the essential goods and services. Dry bulk shipping, a sector characterized by trading versatility and a multitude of cargoes carried, has an important role to play towards that aim. Port restrictions, placed to limit the spread of COVID-19, have created the impression that the market of dry bulk shipping has, to some degree, been affected and become less predictable, as many other transporting services. In this article, this belief is investigated using both state space modeling and neural networks. In particular, using these methods, one-month ahead predictions (during 2020) of the overall freight cost are obtained for three types of vessels (representing the majority of the minor bulks industry). A good forecast performance is observed and this validates the models and the estimation methods proposed. Our results suggest that there is no significant effect of COVID-19 in these types of vessels and their operations. This can provide useful information to shipping managers and policy makers.

Water Treatment Plants treat "flushy" raw waters and the majority use electrolytes and polyelectrolytes for the removal of the solid and organic impurities included in surface waters. The dose of the used reagents depend strongly on the nature of the incoming surface water and its turbidity. Turbidity is due to the suspended particles in the source water and up to date is main criterion for the appropriate choice of the electrolyte and polyelectrolyte nature and dosage. One of the main findings of the present work is that the selection of the appropriate dose of coagulants and flocculants as a linear function of turbidity is not right, especially for the large values of turbidity. The most common electrolytes Aluminum sulfate and PolyAluminiumChloride together with the polyelectrolyte PolyAcrylaMide, are tested for their effectiveness in the removal of suspended particles and their results discussed based on the particle’s ζ-potential and size distribution. These common reagents have raised public health concerns due to the residual aluminium and acrylamide which remain in treated water and at produced sludge. Thus, the present work examined and suggests the use of polymers as the natural Chitosan and CMInulin and the synthetic PolyDiallylDiMethylAmmoniumChloride, as alternative, environmentally friendly coagulants, for their performance on the treatment of potable water. The new reagents proved to reduce the turbidity of the surface water up to 96%.

This study evaluated the methanogenic performance of typical substrates (acetate, formate, H

Open innovation has been found to have many benefits and tangible results for those who partake in it. This study aims to showcase the importance of open innovation, and through a theoretical example present how an organization (university, research center, company, firm, etc.) can take action to implement open innovation guidelines. In this paper, firstly, a demonstration showing how open innovation can work with multiple partners is shown. Secondly, a model is presented that shows the steps an organization must follow to successfully implement open innovation. This model covers the introduction of an organization to open innovation from the initial interest to the implementation of the final product. Several success stories are also presented to demonstrate how these steps have been used by major organizations during several collaborations as well as the results produced from implementing open innovation.

Bioaugmentation is an attractive method to improve methane production (MP) in the anaerobic digestion (AD) process. In this study, to tackle the ammonia inhibition problem, a long-term (operating over 6 months) acclimatized consortia and a well-constructed consortia were selected as the bioaugmentation consortia for sequencing batch AD reactors fed with dairy manure and pig manure under mesophilic condition. Similar responses, in terms of the reactor performance and microorganisms structure to the different consortia, were observed with both manure kinds indicating that the effectiveness of bioaugmentation was mainly decided by the composition of the added consortia, not the feedstock. 39 - 49% increment in MP was obtained in the reactors bioaugmented with well-constructed consortia, which was higher than the acclimatized consortia (about 25% increment in MP). Both acetogenesis and methanogenesis (advantageous) steps were stimulated with well-constructed consortia bioaugmentation. According to key functional enzyme analysis, the increment of glycine hydroxymethyltransferase and phosphoglycerate mutase might be the critical point in the bioaugmented AD system. Based on the higher functional contribution rate of the well-constructed consortia bioaugmentation reactors, Methanosarcina could have expressed more comprehensive functions or performed stronger activities in different functions than Methanosaeta.

The recent breakthroughs in deep neural architectures across multiple machine learning fields have led to the widespread use of deep neural models. These learners are often applied as black-box models that ignore or insufficiently utilize a wealth of preexisting semantic information. In this study, we focus on the text classification task, investigating methods for augmenting the input to deep neural networks (DNNs) with semantic information. We extract semantics for the words in the preprocessed text from the WordNet semantic graph, in the form of weighted concept terms that form a semantic frequency vector. Concepts are selected via a variety of semantic disambiguation techniques, including a basic, a part-of-speech-based, and a semantic embedding projection method. Additionally, we consider a weight propagation mechanism that exploits semantic relationships in the concept graph and conveys a spreading activation component. We enrich word2vec embeddings with the resulting semantic vector through concatenation or replacement and apply the semantically augmented word embeddings on the classification task via a DNN. Experimental results over established datasets demonstrate that our approach of semantic augmentation in the input space boosts classification performance significantly, with concatenation offering the best performance. We also note additional interesting findings produced by our approach regarding the behavior of term frequency - inverse document frequency normalization on semantic vectors, along with the radical dimensionality reduction potential with negligible performance loss. © 2021 Cambridge University Press. All rights reserved.

Introduction: Hidradenitis suppurativa (HS) is a chronic inflammatory skin disorder of the follicular epithelium. The aim of the study was to investigate the effectiveness of colchicine on the clinical outcomes of HS patients, and to evaluate wither colchicine as monotherapy or in combination with doxycycline would provide better outcomes. Methods: A retrospective study was conducted including 44 patients with established HS, divided into three groups. The first group (n = 15 patients) received colchicine as monotherapy, the second group (n = 14 patients) received colchicine and doxycycline 100 mg/d, while the third group (n = 15 patients) received colchicine and doxycycline 40 mg/d. Disease severity during treatment was assessed at baseline and follow-up, using the Hurley Scoring System and the International Hidradenitis Suppurativa Severity Score System (IHS4). All patients were also asked to complete a Dermatology Life Quality Index (DLQI) questionnaire. These scores were compared among the study groups. Results: The DLQI and IHS4 scores significantly improved after treatment with colchicine (p < 0.001) in all groups. All colchicine regimes, including the single colchicine regime, colchicine plus doxycycline 100 mg regime, and colchicine plus doxycycline 40 mg regime, resulted in significant improvements in the DLQI and IHS4 scores (p < 0.001). Clinical improvement based on DLQI and IHS4 scores was similar in all groups. None of the patients had to discontinue the treatment due to adverse events. Discussion: In conclusion, our findings suggest that colchicine may improve clinical severity and quality of life in HS patients, either as monotherapy or in combination with doxycycline, both at antimicrobial (100 mg) and sub-antimicrobial (40 mg) doses.

Ni catalysts based on Al2O3 and Al2O3 modified with CaO-MgO were tested for the dry reforming of biogas (BDR). Time-on-stream experiments were carried out between 600 and 800 °C, and the spent catalysts were examined using a variety of characterization techniques including, N2 adsorption/desorption, thermogravimetric analysis (TGA), Raman spectroscopy, electron microscopy (STEM-HAADF and HR-TEM), and X-ray photoelectron spectroscopy (XPS). It was revealed that the carbon deposits consisted of carbon nanotubes and amorphous carbon for both samples. XPS studies showed the presence of Ni0 on both catalysts and Ni2O3/NiAl2O4 on the Ni/Al2O3 sample. The time-on-stream experiments showed that the Ni/CaO-MgO-Al2O3 catalyst is more resistant to deactivation and more active and selective for all temperatures under investigation. It was concluded that doping Al2O3 with CaO-MgO enhances catalytic performance as: (a) it helps to maintain highly dispersed Ni0 during the BDR as the interaction between metal and support is a stronger one, (b) it leads to the formation of carbon structures that are easier to oxidize, and (c) it facilitates the gasification of the carbon deposits because its increased surface basic sites enhance the adsorption of carbon dioxide.

Choice of the best possible fixation system in terms of safety and effectiveness for intraperitoneal mesh placement in hernia surgery remains controversial. The aim of the present study was to compare the performance of four fixation systems in a swine model of intraperitoneal mesh fixation.Fourteen Landrace swine were utilized in the study. The experiment included two stages. Initially, four pieces of mesh (Ventralight ™ ST) sizing 10 × 5 cm were placed and fixed intraperitoneally to reinforce 4 small full thickness abdominal wall defects created with diathermy. These defects were repaired primarily with absorbable suture before mesh implantation. Each mesh was anchored with a different tack device between Absorbatack™, Protack™, Capsure™, or Optifix™. The second stage took place after 60 days and included euthanasia, laparoscopy, and laparotomy via U-shaped incision to obtain the measurements for the outcome parameters. The primary endpoint of the study was to compare the peel strength of the compound tack/mesh from the abdominal wall. Secondary parameters were the extent and quality of visceral adhesions to the mesh, the degree of mesh shrinkage and the histological response around the tacks.Thirteen out of 14 animals survived the experiment and 10 were included in the final analysis. Capsure™ tacks had higher peel strength when compared to Absorbatack™ (p = 0.028); Protack™ (p = 0.043); and Optifix™ (p = 0.009). No significant differences were noted regarding the extent of visceral adhesions (Friedman's test p value 0.854), the adhesion quality (Friedman's test p value 0.506), or the mesh shrinkage (Friedman's test p value = 0.827). Four out of the ten animals developed no adhesions at all 2 months after implantation.Capsure™ fixation system provided higher peel strength that the other tested devices in our swine model of intraperitoneal mesh fixation. Our findings generate the hypothesis that this type of fixation may be superior in a clinical setting. Clinical trials with long-term follow-up are required to assess the safety and efficacy of mesh fixation systems in hernia surgery.

Greece and China are two agricultural countries in which a significant percentage of their biomass consists of agricultural and livestock wastes. In Greece, the management practice that is still applied is burning the majority of the agricultural residues in the field, while in China large amount of untreated agricultural waste causes serious adverse effects on the rural living environment. Residual biomass could arise from the agricultural sector in the form of crop residues and of animal wastes. A comprehensive literature review was performed for both countries on primary agricultural and livestock wastes that includes: (a) crop residues that are left in the fields, (b) animal manures and (c) secondary agricultural wastes consisted of liquid and solid wastes from agricultural products processing plants. The average annual quantity of agricultural residues, animal manure and agro-industrial residues in Greece and China (a small and a large country, respectively) is 10 Mt/y and 860 Mt/y, 26 Mt/y and 216.5 Mt/y, 13.2 Mt/y and 213.7 Mt/y, for each corresponding category. According to the amount of the above residues generated per country, the theoretical estimated energy can reach up to 77 TWh and 5500 TWh for Greece and China, respectively, which suggests that both countries can cover a significant part of their energy needs (approximately 135% and 99%, respectively) only from their agricultural and livestock wastes. Τhese observations constitute strong recommendations mainly addressed to policy makers to substantially strengthen the efforts of research, technological and economic optimization of the applications of energy use of agricultural residual biomass for the benefit of the environment and humanity.

Upon presenting the particularities of the Arabian Peninsula on the durability of reinforced concrete structures, the procedure and outcomes of a durability analysis using a physicochemical deterministic service life estimation tool on a major infrastructure project of the region, that the authors were invited to perform, are presented. The results show that the initially performed stochastic durability analysis was validated, and further enhancements were proposed. It is argued that a verified physicochemical deterministic approach can produce accurate results under the highly aggressive environment of the Arabian Peninsula, which if necessary, can be further enriched using calibrated reduction (safety) factors.

The paper deals with the understanding of the CO2 capacity of adsorption through the anhydrite cement compound, i.e., CaO·SiO2 structure. The Wollastonite structure is prepared with various CaO/SiO2 ratios for the atomistic simulations. Subsequently, simulations of binary adsorption of H2O and CO2 have been performed to arrive at C–S–H structure. The CaO/SiO2 ratio is varied from 0.66 to less than 1.5 in the present study. The interlayer spacing between CaO sheets is considered as 13.5 A. The impact of the electrostatic charges has been explored using available CLAY_FF and CSH_FF potentials. The outcomes have been successfully examined and compared with experimental results. To understand the capacity adsorption of CO2 and selectivity effect on C–S–H forming, numerical experiments have been performed using CO2 concentrations from 10 ppm up to 1,000,000 ppm at 20 °C. These numerical experiments allow understanding of the selectivity of H2O and CO2 in binary mixture adsorption, and the capacity of CO2 adsorption in the Wollastonite atomic structure. According to the physisorption simulations, the CO2 adsorption capacity depends not only on CO2 concentration but also the Wollastonite structure. The possible CaCO3 precipitation and C–S–H structure are addressed.

This study evaluated the methanogenic performance of typical substrates (acetate, formate, H2/CO2, and glucose) under low and high ammonia levels and the Anaerobic Digestion Model No.1 (ADM1) was extended and modified for better simulation and understanding of the process. Formate-utilizing and hydrogen-utilizing methanogenesis showed stronger ammonia resistance than acetate-utilizing methanogenesis (13-23% vs. 34% decrease in methane production (MP)). Model extension, based on foundational experiments fed with three typical precursors (R2 > 0.92), was then validated with glucose degradation experiments, and satisfactory predictions of MP and total volatile fatty acids were obtained (R2 > 0.91). Based on the modified ADM1, the carbon fluxes of glucose degradation were determined, and formate-utilizing methanogenesis showed its importance with a 28-34% contribution of the total methanation, becoming the dominant pathway under high ammonia level. Formate-utilizing methanogenesis also had a thermodynamic advantage among the three pathways. 16S rRNA sequencing suggested a homology between the hydrogen-utilizing and formate-utilizing methanogens. Methanobacterium and Methanobrevibacter were found to be key methanogens, and their enrichment under high ammonia level confirmed the stronger ammonia tolerance of formate-utilizing and hydrogen-utilizing methanogenesis. The microbial characterization and modified ADM1 simulations supported each other.

In the absence of a carbonation model for soil cement, this research aims to assess the compatibility and applicability of an analytical model initially developed for concrete. Carbonation can be observed in any pavement layer which includes cement or lime. For instance, carbonation damages the cement-modified crushed rocks as a typical material for base course layer due to poor curing of material or cracking of asphalt. Experimental laboratory tests are utilised here in accelerated carbonation conditions to evaluate the analytical model. Cylindrical specimens are subjected to one-dimensional carbonation condition. Weight and ratio of constituents of mixes, as well as environmental factors, such as CO 2 concentration and relative humidity are recorded for analytical estimation of failure progresses. Nanosilica is also introduced in mixes to explore its effects during carbonation reactions. Results show linear correlations between experimental records and analytical model calculations. Thus, it can be concluded that carbonation rate can be predicted in soil cement also. In addition, the inclusion of nanosilica has a positive influences by slowing of the carbonation progress.

Agricultural residues in Greece are amounted to several million tons per year, the olive tree lops (OTL) ranked first with 1.4-3 million tons per year. After the removal of the thicker woods, the rest are burned in the countryside by farmers causing except from energy loss, particularly severe air pollution (greenhouse gases, micro particles, etc.). First objective of this study was to perform a techno-economical analysis of a complete management of OTL in a rural municipality (real application to the Municipality Department of Vasilaki in the Prefecture Laconia, Greece) for the final production of: a) leaves from OTL for extraction of useful constituents, b) bio-compost for soil enhancement and fertilizer and c) pellets for energy applications. From a sensitivity analysis, it was observed that the proposed investment was sensitive in changes of leaves value. Moreover, a change in the price of raw material alters considerably the investment. Generally, the expected profit was considered sufficient and the evaluation criteria (rate on return on initial investment, payout period and net present value) offer very promising results in the direction of undertaking the investment. As the main result, this work envisages to opening up a new road showing a feasible solution of this problem, better than that used nowadays. The proposed solution could be extended to any agricultural residue and can be applied by any interested farmer, enterprise or local authority, offering exploitation of natural resources and enhancement of agriculturist income, especially those in less favored regions.