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1.
Water Res X ; 19: 100170, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-36816494

RESUMO

Digitalisation has developed over half a century and is one of the global trends defining society of today and future. Digitalisation is envisioned to help water utilities to become: i) community orientated and digitally integrated with customers and society; ii) digitally transformed end-to-end throughout the value-chain and interconnected between business units; iii) predictive & proactive, utilizing models and applications for control and decision support; iv) visually communicative with customers and society, creating customers aware of the value of water; and financially sustainable by optimal operation (OPEX), and sustainable investments (CAPEX). Digitalisation is a process for business development, where digital solutions are used for automation and innovation. Utilizing the potential of the technological innovation requires a parallel organisational transformation. Any implementation of systems or applications must be motivated in actual needs for the organisation and service delivery. Prior to any digitalisation, identifying issues and areas of improvement is essential. Starting the digital journey, motivating employees, improving the digital culture and creating acceptance of new processes are needed on all levels. Most digital applications require collection, storage, sharing and integrated analysis of large amounts of data. This includes both soft and hard digital infrastructure.

2.
Int J Mol Sci ; 23(5)2022 Feb 25.
Artigo em Inglês | MEDLINE | ID: mdl-35269677

RESUMO

Oxytocin imprinted polymer nanoparticles were synthesized by glass bead supported solid phase synthesis, with NMR and molecular dynamics studies used to investigate monomer-template interactions. The nanoparticles were characterized by dynamic light scattering, scanning- and transmission electron microscopy and X-ray photoelectron spectroscopy. Investigation of nanoparticle-template recognition using quartz crystal microbalance-based studies revealed sub-nanomolar affinity, kd ≈ 0.3 ± 0.02 nM (standard error of the mean), comparable to that of commercial polyclonal antibodies, kd ≈ 0.02-0.2 nM.


Assuntos
Impressão Molecular , Anticorpos , Impressão Molecular/métodos , Nanogéis , Ocitocina , Polietilenoglicóis , Polietilenoimina , Polímeros/química , Técnicas de Microbalança de Cristal de Quartzo/métodos
3.
Polymers (Basel) ; 13(17)2021 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-34502881

RESUMO

Recent years have witnessed a dramatic increase in the use of theoretical and computational approaches in the study and development of molecular imprinting systems. These tools are being used to either improve understanding of the mechanisms underlying the function of molecular imprinting systems or for the design of new systems. Here, we present an overview of the literature describing the application of theoretical and computational techniques to the different stages of the molecular imprinting process (pre-polymerization mixture, polymerization process and ligand-molecularly imprinted polymer rebinding), along with an analysis of trends within and the current status of this aspect of the molecular imprinting field.

4.
Methods Mol Biol ; 2359: 241-268, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34410675

RESUMO

Molecular dynamics (MD) simulations of prepolymerization mixtures can provide detailed insights concerning the molecular-level mechanisms underlying the performance of molecularly imprinted polymers (MIPs) and can be used for the in silico screening of candidate polymer systems. Here, we describe the use of MD simulations of all-atom, all-component MIP prepolymerization mixtures and procedures for the evaluation of the simulation data using the Amber simulation software suite.


Assuntos
Impressão Molecular , Simulação de Dinâmica Molecular , Polímeros Molecularmente Impressos
5.
Water Sci Technol ; 83(6): 1335-1346, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33767040

RESUMO

This study highlights the need to increase our understanding of the interplay between sensor drift and the performance of the automatic control system. The impact from biased sensors on the automatic control systems is rarely considered when different control strategies are assessed in water resource recovery facilities. Still, the harsh measurement environment with negative effects on sensor data quality is widely acknowledged. Simulations were used to show how sensor bias in an ammonium cascade feedback controller impacts aeration energy efficiency and total nitrogen removal in an activated sludge process. Response surface methodology was used to reduce the required number of simulations, and to consider the combined effect of two simultaneously biased sensors. The effects from flow variations, and negatively biased ammonium (-1 mg/L) and suspended solids sensors (-500 mg/L) reduced the nitrification aeration energy efficiency by between 7 and 25%. Less impact was seen on total nitrogen removal. There were no added non-linear effects from the two simultaneously biased sensors, apart from an interaction between a biased ammonium sensor and dissolved oxygen sensor located in the last aerated zone. Negative effects from sensor bias can partly be limited if the expected bias direction is considered when the controller setpoint-limits are defined.


Assuntos
Oxigênio , Eliminação de Resíduos Líquidos , Reatores Biológicos , Nitrificação , Nitrogênio , Oxigênio/análise , Esgotos
6.
Sci Rep ; 11(1): 4910, 2021 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-33649346

RESUMO

Microglial cells are affected in Alzheimer's disease (AD) and interact with amyloid-beta (Aß) plaques. Apart from memory loss, depression is common in patients with AD. Electroconvulsive therapy (ECT) is an anti-depressive treatment that may stimulate microglia, induce neuroinflammation and alter the levels of soluble Aß, but the effects of ECT on microglia and Aß aggregation in AD are not known. We investigated the short- and long-term effects of ECT on neuroinflammation and Aß accumulation. 5xFAD mice received either electroconvulsive stimulation (ECS n = 26) or sham treatment (n = 25) for 3 weeks. Microglia and Aß were analyzed in samples collected 24 h, 5 weeks, or 9 weeks after the last treatment. Aß plaques and microglia were quantified using immunohistochemistry. The concentration of soluble Aß and cytokines was quantified using ELISA and levels of Aß aggregates were measured with Western Blot. Microglial phagocytosis of Aß in the hippocampus was evaluated by flow cytometry in Methoxy-X04 injected mice 24 h following the last ECS treatment. Y-maze and Elevated plus maze were performed to study behavior after 5 weeks. We could not detect any significant short- or long-term effects of ECS on Aß pathology or neuroinflammation, but ECS reduced abnormal behavior in the Elevated Plus maze.


Assuntos
Doença de Alzheimer/terapia , Eletroconvulsoterapia/métodos , Microglia/patologia , Doenças Neuroinflamatórias/terapia , Placa Amiloide/terapia , Animais , Camundongos , Camundongos Transgênicos
7.
J Am Chem Soc ; 142(26): 11404-11416, 2020 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-32425049

RESUMO

The design of artificial oxyanion receptors with switchable ion preference is a challenging goal in host-guest chemistry. We here report on molecularly imprinted polymers (MIPs) with an external phospho-sulpho switch driven by small molecule modifiers. The polymers were prepared by hydrogen bond-mediated imprinting of the mono- or dianions of phenyl phosphonic acid (PPA), phenyl sulfonic acid (PSA), and benzoic acid (BA) using N-3,5-bis-(trifluoromethyl)-phenyl-N-4-vinylphenyl urea (1) as the functional host monomer. The interaction mode between the functional monomer and the monoanions was elucidated by 1H NMR titrations and 1H-1H NMR NOESY supported by molecular dynamic simulation, which confirmed the presence of high-order complexes. PPA imprinted polymers bound PPA with an equilibrium constant Keq = 1.8 × 105 M-1 in acetonitrile (0.1% 1,2,2,6,6-pentamethylpiperidine) and inorganic HPO42- and SO42- with Keq = 2.9 × 103 M-1 and 4.5 × 103 M-1, respectively, in aqueous buffer. Moreover, the chromatographic retentivity of phosphonate versus sulfonate was shown to be completely switched on this polymer when changing from a basic to an acidic modifier. Mechanistic insights into this system were obtained from kinetic investigations and DSC-, MALDI-TOF-MS-, 1H NMR-studies of linear polymers prepared in the presence of template. The results suggest the formation of template induced 1-1 diad repeats in the polymer main chain shedding unique light on the relative contributions of configurational and conformational imprinting.

8.
Bioresour Technol ; 302: 122824, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32000132

RESUMO

This paper presents a modelling study aimed at minimizing the environmental foot print of a membrane bioreactor (MBR) for wastewater treatment. Specifically, an integrated model for MBR was employed in view of the management optimization of an MBR biological nutrient removal (BNR) pilot plant in terms of operational costs and direct greenhouse gases emissions. The influence of the operational parameters (OPs) on performance indicators (PIs) was investigated by adopting the Extended-FAST sensitivity analysis method. Further, a multi-objective analysis was performed by applying the Technique for Order of Preference by Similarity to Ideal Solution (TOPSIS). The results show-up that the sludge retention time is the OP mostly affecting all the investigated PIs. By applying the set of optimal OPs, there was a reduction of 48% and 10% of the operational costs and direct emissions, respectively.


Assuntos
Gases de Efeito Estufa , Eliminação de Resíduos Líquidos , Reatores Biológicos , Membranas Artificiais , Esgotos , Águas Residuárias
9.
Int J Mol Sci ; 20(12)2019 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-31212745

RESUMO

A family of non-ionic deep eutectic liquids has been developed based upon mixtures of solid N-alkyl derivatives of urea and acetamide that in some cases have melting points below room temperature. The eutectic behaviour and physical characteristics of a series of eleven eutectic mixtures are presented, along with a molecular dynamics study-supported hypothesis for the origin of the non-ideal mixing of these substances. Their use as solvents in applications ranging from natural product extraction to organic and polymer synthesis are demonstrated.


Assuntos
Acetamidas/química , Solventes/química , Temperatura , Ureia/química , Ligação de Hidrogênio , Simulação de Dinâmica Molecular , Estrutura Molecular , Solubilidade , Análise Espectral
10.
Water Res ; 155: 381-402, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30861379

RESUMO

Instrumentation, control and automation (ICA) are currently applied throughout the urban water system at water treatment plants, in water distribution networks, in sewer networks, and at wastewater treatment plants. However, researchers and practitioners specialising in respective urban water sub-systems do not frequently interact, and in most cases to date the application of ICA has been achieved in silo. Here, we review start-of-the-art ICA throughout these sub-systems, and discuss the benefits achieved in terms of performance improvement, cost reduction, and more importantly, the enhanced capacity of the existing infrastructure to cope with increased service demand caused by population growth and continued urbanisation. We emphasise the importance of integrated control within each of the sub-systems, and also across the entire urban water system. System-wide ICA will have increasing importance with the growing complexity of the urban water environment in cities of the future.


Assuntos
Sudorese , Água , Automação , Cidades , Eliminação de Resíduos Líquidos , Águas Residuárias , Abastecimento de Água
11.
Sci Total Environ ; 619-620: 721-731, 2018 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-29161597

RESUMO

Water availability and water demand are not evenly distributed in time and space. Many mega water diversion projects have been launched to alleviate water shortages in China. This paper analyzes the temporal and spatial features of 59 mega water diversion projects in China using statistical analysis. The relationship between nine major basins is measured using a network analysis method, and the associated economic, environmental and social impacts are explored using an impact analysis method. The study finds the development of water diversion has experienced four stages in China, from a starting period through to a period of high-speed development. Both the length of water diversion channels and the amount of transferred water have increased significantly in the past 50years. As of 2015, over 100billionm3 of water was transferred in China through 16,000km in channels. These projects reached over half of China's provinces. The Yangtze River Basin is now the largest source of transferred water. Through inter-basin water diversion, China gains the opportunity to increase Gross Domestic Product by 4%. However, the construction costs exceed 150 billion US dollars, larger than in any other country. The average cost per unit of transferred water has increased with time and scale but decreased from western to eastern China. Furthermore, annual total energy consumption for pumping exceeded 50billionkilowatt-hours and the related greenhouse gas emissions are estimated to be 48milliontons. It is worth noting that ecological problems caused by water diversion affect the Han River and Yellow River Basins. Over 500 thousand people have been relocated away from their homes due to water diversion. To improve the sustainability of water diversion, four kinds of innovative measures have been provided for decision makers: national diversion guidelines, integrated water basin management, economic incentives and ex-post evaluation.

12.
Bioresour Technol ; 241: 1145-1151, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28579177

RESUMO

The present study explores the interlinkages among the operational variables of a University of Cape Town (UCT) Integrated Fixed Film Activated Sludge (IFAS) membrane bioreactor (MBR) pilot plant. Specifically, dedicated experimental tests were carried out with the final aim to find-out a constitutive relationship among operational costs (OCs), effluent quality index (EQI), effluent fines (EF). Greenhouse gas (GHG) emissions were also included in the study. Results showed that the EQI increases at low flow rate likely due to the dissolved oxygen (DO) limitation in the biological processes. Direct GHGs increase with the increasing of the air flow due to the anoxic N2O contribution. Irreversible membrane fouling reduce from 98% to 85% at the air flow rate of 0.57m3h-1 and 2.56m3h-1, respectively. However, the increase of the air flow rate leads to the increase of the N2O-N flux emitted from the MBR (from 40% to 80%).


Assuntos
Reatores Biológicos , Esgotos , Oxigênio , Eliminação de Resíduos Líquidos
13.
Glob Chall ; 1(5): 1600015, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31565275

RESUMO

Water resources and water quality are closely related to oil exploration, refining and distribution. Since oil products provide over 90% of transport energy in almost all countries it is apparent that any oil operation is an inherent risk for water resources. Since water supplies will be increasingly stressed as a consequence of climate change and population increase the environmental risks associated with oil exploration may intensify. Thus, there are more reasons than CO2 emissions and climate change to cut down on oil production and consumption. In this paper water related risks are discussed from two aspects: (1) water use and water pollution as a result of normal exploration, refining and distribution, (2) water and marine life contamination caused by accidents. It will be exemplified by some major oil accidents, too often caused by human errors or negligence. Ecological effects of oil contamination for seawaters and freshwaters are discussed. Some aspects of social and economic consequences are examined. Some possibilities for mitigating oil leakage risks are highlighted.

14.
Glob Chall ; 1(5): 1600022, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31565278

RESUMO

Renewable energy technologies can make a major contribution to universal access to both energy and water in a sustainable way. In many regions of the world with energy poverty there are abundant renewable energy sources. In this review it is described how solar photovoltaic (PV) and wind energy have a huge potential to supply clean water, in particular in areas with no grid connection. Off-grid technologies can form a significant part of the solution, all the way from household level to village or community level. Small scale off-grid systems can provide not only lighting but also energy for pumping to gain access to water and to purify and re-use water. In rapidly growing peri-urban areas electric power grids may be available but need to be complemented with decentralized energy sources. Solar and wind can be part of a new kind of hybrid energy supplies. It is noted that there is a confluence of factors, such as greater urbanization, population increase, economic development that will determine the energy mix. The United Nations Sustainable Development Goals of clean water and energy for all are strongly related and will depend to a large extent on solar PV and wind.

15.
Glob Chall ; 1(5): 1700056, 2017 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-31565280
16.
Org Biomol Chem ; 14(18): 4210-9, 2016 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-27043914

RESUMO

All-component molecular dynamics studies were used to probe a library of oseltamivir molecularly imprinted polymer prepolymerization mixtures. Polymers included one of five functional monomers (acrylamide, hydroxyethylmethacrylate, methacrylic acid, 2-(triflouromethyl)acrylic acid, 4-vinylpyridine) and one of three porogens (acetonitrile, chloroform, methanol) combined with the crosslinking agent ethylene glycol dimethacrylate and initiator 2,2'-azobis(2-methylpropionitrile). Polymers were characterized by nitrogen gas sorption measurements and SEM, and affinity studies performed using radioligand binding in various media. In agreement with the predictions made from the simulations, polymers prepared in acetonitrile using either methacrylic or trifluoromethacrylic acid demonstrated the highest affinities for oseltamivir. Further, the ensemble of interactions observed in the methanol system provided an explanation for the morphology of polymers prepared in this solvent. The materials developed here offer potential for use in solid-phase extraction or for catalysis. The results illustrate the strength of this in silico strategy as a potential prognostic tool in molecularly imprinted polymer design.


Assuntos
Simulação por Computador , Simulação de Dinâmica Molecular , Impressão Molecular , Oseltamivir/química , Polímeros/síntese química , Conformação Molecular , Polímeros/química
17.
Sci Total Environ ; 551-552: 254-70, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-26878638

RESUMO

Nitrous oxide, carbon dioxide and methane are greenhouse gases (GHG) emitted from wastewater treatment that contribute to its carbon footprint. As a result of the increasing awareness of GHG emissions from wastewater treatment plants (WWTPs), new modelling, design, and operational tools have been developed to address and reduce GHG emissions at the plant-wide scale and beyond. This paper reviews the state-of-the-art and the recently developed tools used to understand and manage GHG emissions from WWTPs, and discusses open problems and research gaps. The literature review reveals that knowledge on the processes related to N2O formation, especially due to autotrophic biomass, is still incomplete. The literature review shows also that a plant-wide modelling approach that includes GHG is the best option for the understanding how to reduce the carbon footprint of WWTPs. Indeed, several studies have confirmed that a wide vision of the WWPTs has to be considered in order to make them more sustainable as possible. Mechanistic dynamic models were demonstrated as the most comprehensive and reliable tools for GHG assessment. Very few plant-wide GHG modelling studies have been applied to real WWTPs due to the huge difficulties related to data availability and the model complexity. For further improvement in GHG plant-wide modelling and to favour its use at large real scale, knowledge of the mechanisms involved in GHG formation and release, and data acquisition must be enhanced.


Assuntos
Poluição do Ar/estatística & dados numéricos , Monitoramento Ambiental/métodos , Modelos Químicos , Eliminação de Resíduos Líquidos/métodos , Poluentes Atmosféricos/análise , Dióxido de Carbono/análise , Efeito Estufa , Metano/análise , Óxido Nitroso/análise , Eliminação de Resíduos Líquidos/estatística & dados numéricos , Águas Residuárias/química , Águas Residuárias/estatística & dados numéricos
18.
Adv Biochem Eng Biotechnol ; 150: 25-50, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25786710

RESUMO

The development of in silico strategies for the study of the molecular imprinting process and the properties of molecularly imprinted materials has been driven by a growing awareness of the inherent complexity of these systems and even by an increased awareness of the potential of these materials for use in a range of application areas. Here we highlight the development of theoretical and computational strategies that are contributing to an improved understanding of the mechanisms underlying molecularly imprinted material synthesis and performance, and even their rational design.


Assuntos
Simulação por Computador , Modelos Químicos , Impressão Molecular/métodos , Polímeros/química , Polímeros/síntese química
19.
Bioresour Technol ; 181: 291-6, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25661308

RESUMO

Aerobic granulation is increasingly used in wastewater treatment due to its unique physical properties and microbial functionalities. Granule size defines the physical properties of granules based on biomass accumulation. This study aims to determine the profile of size development under two physicochemical conditions. Two identical bioreactors namely Rnp and Rp were operated under non-phototrophic and phototrophic conditions, respectively. An illustrative scheme was developed to comprehend the mechanism of size development that delineates the granular size throughout the granulation. Observations on granules' size variation have shown that activated sludge revolutionised into the form of aerobic granules through the increase of biomass concentration in bioreactors which also determined the changes of granule size. Both reactors demonstrated that size transformed in a similar trend when tested with and without illumination. Thus, different types of aerobic granules may increase in size in the same way as recommended in the aerobic granule size development scheme.


Assuntos
Tamanho da Partícula , Esgotos/química , Aerobiose , Biomassa , Reatores Biológicos , Águas Residuárias
20.
Int J Mol Sci ; 15(6): 10622-34, 2014 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-24927149

RESUMO

Aspects of the molecular-level basis for the function of ethylene glycol dimethacrylate and trimethylolproprane trimethacrylate crosslinked methacrylic acid copolymers molecularly imprinted with (S)-propranolol have been studied using a series of all-component and all-atom molecular dynamics studies of the corresponding prepolymerization systems. The crosslinking agents were observed to contribute to template complexation, and the results were contrasted with previously reported template-recognition behavior of the corresponding polymers. Differences in the extent to which the two crosslinkers interacted with the functional monomer were identified, and correlations were made to polymer-ligand recognition behavior and the results of nuclear magnetic resonance spectroscopic studies studies. This study demonstrates the importance of considering the functional monomer-crosslinker interaction when designing molecularly imprinted polymers, and highlights the often neglected general contribution of crosslinker to determining the nature of molecularly imprinted polymer-template selectivity.


Assuntos
Impressão Molecular , Polímeros/química , Espectroscopia de Ressonância Magnética , Metacrilatos/química , Simulação de Dinâmica Molecular
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