Kogeneracija i povrat topline u industrijskom postupku

Related to energy requirements for non-cellulose i. e. polyester production as an energy-intensive process, potential saving options are proposed. From the process data, it is evident that unit operations need electric and thermal energy in significant amounts. At the same time, improved energy management could be realized by applying a combined heat and power system (CHP) instead of the usually used process with separate heat and power production. In addition, the boiler flue gases with a sufficiently high outlet temperature could be used for combustion air preheating. Considering industrial process data, a calculation and comparison between the primary energy demand for conventional, CHP system and flue-gas heat recovery is presented. Comparison between separate heat and electricity production i.e. the conventional system with an overall efficiency of 55.6 % and CHP with efficiency of 85 %, shows an absolute efficiency increase of 29.4 %. Using an air preheater for combustion air temperature increasing saves 5.6 % of the fuel and at the same time diminishes thermal pollution because the exhaust flue-gas temperature becomes 77.3 °C instead of 204°C. Conclusively, cogeneration and flue-gas heat recovery presents fuel savings, which also implies economic and environmental benefits.Predložene su mogućnosti uštede energije u industrijskoj proizvodnji poliestera kao energetski intenzivnom procesu. Iz procesnih podataka proizlazi značajna potrošnja električne i toplinske energije u procesnim operacijama. Istodobno, poboljšanje gospodarenja energijom moguće je ostvariti primjenom kogeneracije, tj. zajedničke proizvodnje toplinske i električne energije kao zamjene za uobičajenu odvojenu proizvodnju istih. Nadalje, plinovi izgaranja sa zadovoljavajućom temperaturnom razinom mogu se upotrebljavati radi predgrijavanja zraka za izgaranje. U skladu s procesnim podacima provedeni su proračuni i usporedba potrošnje energije za konvencionalni i kogeneracijski sustav kao i povrat topline dimnih plinova. Komparacija odvojene proizvodnje toplinske i električne energije s učinkovitošću od 55,6 % i kogeneracije s 85 % ukazuje na porast apsolutnog iskorištenja od 29,4 %. Primjenom predgrijača radi povišenja temperature zraka za izgaranje ušteda goriva je 5,6%. Time se istodobno smanjuje toplinsko opterećenje okoliša što rezultira iz sniženja izlazne temperature dimnih plinova od oko 127 °C. Zaključno, kogeneracija i povrat topline dimnih plinova osim sniženja specifične potrošnje energije rezultira ekološkim i gospodarstvenim prednostima

Effect of equivalent salt deposit density on flashover voltage of contaminated insulator energized by HVDC

In Malaysia, the demand for electric power is increasing day by day due to more consumption of power in the industrial sector. Recently, the high voltage DC transmission lines are under construction near the coastal environments for transmitting the power to the all states of Malaysia. Therefore, there is a concern about the reliability of these systems especially under adverse environmental conditions due to sea salt spray contamination. This reliability of this contaminated insulator can be improved through its performance studies. For this performance study, an analytical expression between flashover voltage and ESDD of the contaminated insulator has been proposed using Dimensional Analysis technique. The results obtained from the analytical expression are compared with the experimental results and in close agreement are foun

The Key Criteria in Deciding to Tender for Construction Projects

Planning for a construction project is a formidable task which involves a huge investment with multiple stakeholders such as clients, consultants, and contractors. A tender is a submission of a technical, administrative, and contractual material made by a potential contractor in response to an invitation to tender by the project client. Established contractors normally realise the importance of doing initial research before committing themselves to enter the tender. Normally, tender pre-qualification is a strict process. A low-quality tender submitted due to problems such as insufficient time and incomplete tender documents normally lead to tender rejection by the client. Thus, this research aimed to provide a strategy to help the contractors in deciding whether they should or should not submit a tender at the initial tendering decision phase. The literature review was focused on the key factors identified in influencing the decision-making process and in the final part, the initial conceptual model was establishe

Towards a data sharing Code of Conduct for international genomic research

Data sharing is increasingly regarded as an ethical and scientific imperative that advances knowledge and thereby respects the contributions of the participants. Because of this and the ever-increasing amount of data access requests currently filed around the world, three groups have decided to develop data sharing principles specific to the context of collaborative international genomics research. These groups are: the international Public Population Project in Genomics (P3G), an international consortium of projects partaking in large-scale genetic epidemiological studies and biobanks; the European Network for Genetic and Genomic Epidemiology (ENGAGE), a research project aiming to translate data from large-scale epidemiological research initiatives into relevant clinical information; and the Centre for Health, Law and Emerging Technologies (HeLEX). We propose seven different principles and a preliminary international data sharing Code of Conduct for ongoing discussion

DataSHIELD:An Ethically Robust Solution to Multiple-Site Individual-Level Data Analysis

&lt;b&gt;&lt;i&gt;Background:&lt;/i&gt;&lt;/b&gt; DataSHIELD (Data Aggregation Through Anonymous Summary-statistics from Harmonised Individual levEL Databases) has been proposed to facilitate the co-analysis of individual-level data from multiple studies without physically sharing the data. In a previous paper, we investigated whether DataSHIELD could protect participant confidentiality in accordance with UK law. In this follow-up paper, we investigate whether DataSHIELD addresses a broader range of ethics-related data-sharing concerns. &lt;b&gt;&lt;i&gt;Methods:&lt;/i&gt;&lt;/b&gt; Ethics-related data-sharing concerns of Institutional Review Boards, ethics experts, international research consortia and research participants were identified through a literature search and systematically examined at a multidisciplinary workshop to determine whether DataSHIELD proposes mechanisms which can address these concerns. &lt;b&gt;&lt;i&gt;Results:&lt;/i&gt;&lt;/b&gt; DataSHIELD addresses several ethics-related data-sharing concerns related to privacy, confidentiality, and the protection of the research participant's rights while sharing data and after the data have been shared. The data remain entirely under the direct management of the study that collected them. Data processing commands are strictly supervised, and the data are queried in a protected environment. Issues related to the return of individual research results when data are shared are eliminated; the responsibility for return remains at the study of origin. &lt;b&gt;&lt;i&gt;Conclusion:&lt;/i&gt;&lt;/b&gt; DataSHIELD can provide an innovative and robust solution for addressing commonly encountered ethics-related data-sharing concerns.</jats:p

The origin of large molecules in primordial autocatalytic reaction networks

Large molecules such as proteins and nucleic acids are crucial for life, yet their primordial origin remains a major puzzle. The production of large molecules, as we know it today, requires good catalysts, and the only good catalysts we know that can accomplish this task consist of large molecules. Thus the origin of large molecules is a chicken and egg problem in chemistry. Here we present a mechanism, based on autocatalytic sets (ACSs), that is a possible solution to this problem. We discuss a mathematical model describing the population dynamics of molecules in a stylized but prebiotically plausible chemistry. Large molecules can be produced in this chemistry by the coalescing of smaller ones, with the smallest molecules, the `food set', being buffered. Some of the reactions can be catalyzed by molecules within the chemistry with varying catalytic strengths. Normally the concentrations of large molecules in such a scenario are very small, diminishing exponentially with their size. ACSs, if present in the catalytic network, can focus the resources of the system into a sparse set of molecules. ACSs can produce a bistability in the population dynamics and, in particular, steady states wherein the ACS molecules dominate the population. However to reach these steady states from initial conditions that contain only the food set typically requires very large catalytic strengths, growing exponentially with the size of the catalyst molecule. We present a solution to this problem by studying `nested ACSs', a structure in which a small ACS is connected to a larger one and reinforces it. We show that when the network contains a cascade of nested ACSs with the catalytic strengths of molecules increasing gradually with their size (e.g., as a power law), a sparse subset of molecules including some very large molecules can come to dominate the system.Comment: 49 pages, 17 figures including supporting informatio

Healthy minds 0-100 years: Optimising the use of European brain imaging cohorts ("Lifebrain").

The main objective of "Lifebrain" is to identify the determinants of brain, cognitive and mental (BCM) health at different stages of life. By integrating, harmonising and enriching major European neuroimaging studies across the life span, we will merge fine-grained BCM health measures of more than 5000 individuals. Longitudinal brain imaging, genetic and health data are available for a major part, as well as cognitive and mental health measures for the broader cohorts, exceeding 27,000 examinations in total. By linking these data to other databases and biobanks, including birth registries, national and regional archives, and by enriching them with a new online data collection and novel measures, we will address the risk factors and protective factors of BCM health. We will identify pathways through which risk and protective factors work and their moderators. Exploiting existing European infrastructures and initiatives, we hope to make major conceptual, methodological and analytical contributions towards large integrative cohorts and their efficient exploitation. We will thus provide novel information on BCM health maintenance, as well as the onset and course of BCM disorders. This will lay a foundation for earlier diagnosis of brain disorders, aberrant development and decline of BCM health, and translate into future preventive and therapeutic strategies. Aiming to improve clinical practice and public health we will work with stakeholders and health authorities, and thus provide the evidence base for prevention and intervention.This research is funded by the EU Horizon 2020 Grant: ‘Healthy minds 0–100 years: Optimising the use of European brain imaging cohorts (“Lifebrain”)’. Grant agreement number: 732592. Call: Societal challenges: Health, demographic change and well-bein

The Global Brain Health Survey: Development of a Multi-Language Survey of Public Views on Brain Health.

Background: Brain health is a multi-faceted concept used to describe brain physiology, cognitive function, mental health and well-being. Diseases of the brain account for one third of the global burden of disease and are becoming more prevalent as populations age. Diet, social interaction as well as physical and cognitive activity are lifestyle factors that can potentially influence facets of brain health. Yet, there is limited knowledge about the population's awareness of brain health and willingness to change lifestyle to maintain a healthy brain. This paper introduces the Global Brain Health Survey protocol, designed to assess people's perceptions of brain health and factors influencing brain health. Methods: The Global Brain Health Survey is an anonymous online questionnaire available in 14 languages to anyone above the age of 18 years. Questions focus on (1) willingness and motivation to maintain or improve brain health, (2) interest in learning more about individual brain health using standardized tests, and (3) interest in receiving individualized support to take care of own brain health. The survey questions were developed based on results from a qualitative interview study investigating brain health perceptions among participants in brain research studies. The survey includes 28 questions and takes 15-20 min to complete. Participants provide electronically informed consent prior to participation. The current survey wave was launched on June 4, 2019 and will close on August 31, 2020. We will provide descriptive statistics of samples distributions including analyses of differences as a function of age, gender, education, country of residence, and we will examine associations between items. The European Union funded Lifebrain project leads the survey in collaboration with national brain councils in Norway, Germany, and Belgium, Brain Foundations in the Netherlands and Sweden, the National University of Ostroh Academy and the Women's Brain Project. Discussion: Results from this survey will provide new insights in peoples' views on brain health, in particular, the extent to which the adoption of positive behaviors can be encouraged. The results will contribute to the development of policy recommendations for supporting population brain health, including measures tailored to individual needs, knowledge, motivations and life situations

Genome-Wide Identification of Small RNAs in the Opportunistic Pathogen Enterococcus faecalis V583

Small RNA molecules (sRNAs) are key mediators of virulence and stress inducible gene expressions in some pathogens. In this work we identify sRNAs in the Gram positive opportunistic pathogen Enterococcus faecalis. We characterized 11 sRNAs by tiling microarray analysis, 5′ and 3′ RACE-PCR, and Northern blot analysis. Six sRNAs were specifically expressed at exponential phase, two sRNAs were observed at stationary phase, and three were detected during both phases. Searches of putative functions revealed that three of them (EFA0080_EFA0081 and EFB0062_EFB0063 on pTF1 and pTF2 plasmids, respectively, and EF0408_EF04092 located on the chromosome) are similar to antisense RNA involved in plasmid addiction modules. Moreover, EF1097_EF1098 shares strong homologies with tmRNA (bi-functional RNA acting as both a tRNA and an mRNA) and EF2205_EF2206 appears homologous to 4.5S RNA member of the Signal Recognition Particle (SRP) ribonucleoprotein complex. In addition, proteomic analysis of the ΔEF3314_EF3315 sRNA mutant suggests that it may be involved in the turnover of some abundant proteins. The expression patterns of these transcripts were evaluated by tiling array hybridizations performed with samples from cells grown under eleven different conditions some of which may be encountered during infection. Finally, distribution of these sRNAs among genome sequences of 54 E. faecalis strains was assessed. This is the first experimental genome-wide identification of sRNAs in E. faecalis and provides impetus to the understanding of gene regulation in this important human pathogen