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1.
PLoS One ; 15(3): e0227368, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32130215

RESUMO

The idea that households produce and consume their own energy, that is, energy self-sufficiency at a very local level, captures the popular imagination and commands political support across parts of Europe. This paper investigates the technical and economic feasibility of household energy self-sufficiency in Switzerland, which can be seen as representative for other regions with a temperate climate, by 2050. We compare sixteen cases that vary across four dimensions: household type, building type, electricity demand reduction, and passenger vehicle use patterns. We assume that photovoltaic (PV) electricity supplies all energy, which implies a complete shift away from fossil fuel based heating and internal combustion engine vehicles. Two energy storage technologies are considered: short-term storage in lithium-ion batteries and long-term storage with hydrogen, requiring an electrolyzer, storage tank, and a fuel cell for electricity conversion. We examine technological feasibility and total system costs for self-sufficient households compared to base cases that rely on fossil fuels and the existing power grid. PV efficiency and available rooftop/facade area are most critical with respect to the overall energy balance. Single-family dwellings with profound electricity demand reduction and urban mobility patterns achieve self-sufficiency most easily. Multi-family buildings with conventional electricity demand and rural mobility patterns can only be self-sufficient if PV efficiency increases, and all of the roof plus most of the facade can be covered with PV. All self-sufficient cases are technically feasible but more expensive than fully electrified grid-connected cases. Self-sufficiency may even become cost-competitive in some cases depending on storage and fossil fuel prices. Thus, if political measures improve their financial attractiveness or individuals decide to shoulder the necessary investments, self-sufficient buildings may start to become increasingly prevalent.


Assuntos
Poluição do Ar/prevenção & controle , Clima , Indústria da Construção/métodos , Fontes de Energia Elétrica/economia , Semicondutores/economia , Automóveis/economia , Mudança Climática , Indústria da Construção/economia , Indústria da Construção/tendências , Fontes de Energia Elétrica/tendências , Eletrólise/economia , Estudos de Viabilidade , Combustíveis Fósseis/efeitos adversos , Humanos , Hidrogênio/química , Hidrogênio/economia , Lítio/química , Lítio/economia , Densidade Demográfica , Suíça
2.
Macromol Rapid Commun ; 41(4): e1900437, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31894897

RESUMO

In the past 20 years, organic solar cells (OSCs) have made great progress in pursuing high power-conversion efficiencies, reaching the application threshold. Instead, device stability is becoming particularly important toward commercialization. There are many factors influencing the stability of OSCs, such as light, heat, humidity, oxygen, as well as device structure. Active layer materials, as the most critical functional layer in the devices, are greatly affected by these factors in terms of both efficiency and stability. Herein, it is desirable and urgent to summarize methods for obtaining active layer materials with long-term stability, mainly focusing on the chemical structure and blending morphology. Meanwhile, the corresponding degraded mechanism of OSCs is concluded and analyzed. In this outlook, challenges for developing high-performance and stable OSCs are discussed.


Assuntos
Compostos Orgânicos/química , Polímeros/química , Fontes de Energia Elétrica/tendências , Desenho de Equipamento/instrumentação , Temperatura Alta/efeitos adversos , Umidade/efeitos adversos , Ciência dos Materiais , Oxigênio/efeitos adversos , Energia Solar
3.
Environ Sci Pollut Res Int ; 26(29): 29883-29895, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31410831

RESUMO

This simulation study is aimed to model a contemporary Proton Exchange Membrane fuel cell (PEMFC) CHP system having a 'heat and power' autonomy as well as a provision of demand-driven electrical supply to the grid. A novel nanowire-electrode PEMFC stack is adopted within this PEMFC CHP system so to effectively replace the existing natural gas fuelled durable solid oxide fuel cell (SOFC) CHP system installed at David Wilson Millennium Eco-house at University of Nottingham. The energy savings, environmental, and economic performances of the proposed PEMFC system are determined and compared to the base case (SOFC) which is operated continuously to maintain a 1.5 kWe. While to meetup the highly fluctuating and seasonal demands of heating and power like in the UK, a PEMFC is more productive and advantageous over a SOFC. The proposed PEMFC unlike to the SOFC will be able to operate and adjust its output and turn down instantly as per changing conditions of ambient temperatures and loads in terms of electricity and heat. The results of the modelling predicted that as compared to the base case scenario, this PEMFC CHP system will efficiently reduce an annual CO2 emission by 65.99% and fiscal costs by 66.74% with a viable internal rate of return as 8.93% and benefit to cost ratio as 1.02.


Assuntos
Dióxido de Carbono/análise , Fontes de Energia Elétrica , Eletricidade , Arquitetura de Instituições de Saúde/métodos , Calefação , Modelos Teóricos , Fontes de Energia Elétrica/economia , Fontes de Energia Elétrica/tendências , Eletrodos , Arquitetura de Instituições de Saúde/economia , Nanofios , Óxidos , Prótons , Reino Unido
4.
PLoS One ; 14(7): e0219326, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31295278

RESUMO

The Sustainable Energy Development Authority of Malaysia (SEDA) regularly receives complaints about damaged components and distribution boards of PV systems due to lightning strikes. Permanent and momentary interruptions of distribution circuits may also occur from the disturbance. In this paper, a solar PV Rooftop system (3.91 kWp) provided by SEDA was modelled in the PSCAD/EMTDC. The Heidler function was used as a lightning current waveform model to analyse the transient current and voltage at two different points susceptible to the influence of lightning events such as different lightning current wave shape, standard lightning current and non-standard lightning current. This study examines the effect on the system components when lightning directly strikes at two different points of the installation. The two points lie between the inverter and the solar PV array and between inverter and grid. Exceptionally high current and voltage due to the direct lightning strike on a certain point of a PV Rooftop system was also studied. The result of this case study is observed with and without the inclusion of surge protective devices (SPDs). The parameters used were 31 kA of peak current, 10 metres cable length and lightning impulse current wave shape of 8/20µs. The high current and voltage at P1 striking point were 31 kA and 2397 kV, respectively. As for the AC part, the current and voltage values were found to be 5.97 kA and 5392 kV, respectively.Therefore, SPDs with suitable rating provided by SEDA were deployed. Results showed that high transient current voltage is expected to clamp sharply at the values of 1.915 kV and 0 A at the P1 striking point. As for the AC part, the current and voltage values were found to be 0 kA and 0.751 V, respectively. Varying lightning impulse current wave shapes at striking point P2 showed that the highest voltage was obtained at waveshape 10/350 µs at 11277 kV followed by wave shapes of 2/70 µs, 8/20 µs and 0.7/6 µs. The high value of transient voltage was clamped at a lower level of 2.029 kV. Different lightning amplitudes were also applied, ranging from 2-200 kA selected based on the CIGRE distribution. It showed that the current and voltage at P1 and P2 were directly proportional. Therefore, the SPD will be designed at an acceptable rating and proper position of SPD installation at solar PV Rooftop will be proposed. The results obtained in this study can then be utilised to appropriately assign a SPD to protect the PV systems that are connected to the grid. Installing SPDs without considering the needs of lightning protection zones would expose the expensive equipment to potential damage even though the proper energy coordination of SPDs is in place. As such, the simulation results provide a basis for controlling the impacts of direct lightning strikes on electrical equipment and power grids and thus justify SPD coordination to ensure the reliability of the system.


Assuntos
Fontes de Energia Elétrica/tendências , Fenômenos Eletromagnéticos , Relâmpago , Sistemas Computacionais , Eletrodos , Hospitais/provisão & distribução , Humanos , Malásia , Reprodutibilidade dos Testes
5.
Brain Stimul ; 12(4): 845-850, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30876884

RESUMO

BACKGROUND: People with Parkinson's disease (PD) treated with deep brain stimulation (DBS) with non-rechargeable implantable pulse generators (IPGs) require elective IPG replacement operations involving surgical and anesthesiologic risk. Life expectancy and the number of replacements per patient with DBS are increasing. OBJECTIVE: To determine whether IPG longevity is influenced by stimulation parameters alone or whether there is an independent effect of the number of battery replacements and IPG model. METHODS: PD patients treated with bilateral subthalamic DBS were included if there was at least one IPG replacement due to battery end of life. Fifty-five patients had one or two IPG replacements and seven had three or four replacements, (80 Kinetra® and 23 Activa-PC®). We calculated longevity corrected for total electrical energy delivered (TEED) and tested for the effect of IPG model and number of previous battery replacements on this measure. RESULTS: TEED-corrected IPG longevity for the 1st implanted IPG was 51.3 months for Kinetra® and 35.6 months for Activa-PC®, which dropped by 5.9 months and 2.8 months, respectively with each subsequent IPG replacement (p < 10-6 for IPG model and p < 10-3 for IPG number). CONCLUSIONS: Activa-PC® has shorter battery longevity than the older Kinetra®, battery longevity reduces with repeated IPG replacements and these findings are independent of TEED. Battery longevity should be considered both in clinical decisions and in the design of new DBS systems. Clinicians need accessible, reliable and user-friendly tools to provide online estimated battery consumption and end of life. Furthermore, this study supports the consideration of using rechargeable IPGs in PD.


Assuntos
Tomada de Decisão Clínica/métodos , Estimulação Encefálica Profunda/tendências , Fontes de Energia Elétrica/tendências , Eletrodos Implantados/tendências , Doença de Parkinson/terapia , Idoso , Estimulação Encefálica Profunda/instrumentação , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico , Estudos Retrospectivos , Fatores de Tempo
6.
Brain Stimul ; 12(4): 851-857, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30842036

RESUMO

BACKGROUND: Deep brain stimulation (DBS) of the subthalamic nucleus (STN) is a well-established treatment for motor complications in Parkinson disease (PD). Since 2012, the nonrechargeable dual-channel neurostimulator available in France seems to have shorter battery longevity compared to the same manufacturer's previous model. OBJECTIVE: The aim of this study was to evaluate the battery longevity of older and more recent neurostimulators from the same manufacturer and to explore factors associated with battery life variations. MATERIALS AND METHODS: We retrospectively studied our cohort of PD patients who underwent STN DBS between 1987 and 2017. We collected data concerning neurostimulator replacements and parameters. We compared the survival of the first device available, Kinetra® and the current one, Activa-PC® (Medtronic Inc.) and estimated the factors that had an impact on battery longevity through a Cox logistic regression. RESULTS: Three hundred sixty-four PD patients received a total of 654 DBS STN neurostimulators: 317 Kinetra® and 337 Activa-PC®. The survival analysis, using the Kaplan-Meier estimator, showed a difference between the curves of the two devices (log-rank test; p < 0.001). The median survival of an Activa-PC® neurostimulator was 1666 days, while it was 2379 days for a Kinetra®. After adjustment, according to the multivariate analysis, the main factors associated with battery lifetime were: the neurostimulator type; the number of subsequent neurostimulator implantations; the total electrical energy delivered (TEED); and sex. CONCLUSION: The Kinetra® neurostimulator lifetime is 2.5 years longer than the Activa-PC®. The type of the device, the high TEED and the number of subsequent neurostimulator implantations influence battery longevity most. These results have medical-economic implications since the survival of PD patients with DBS increases over years.


Assuntos
Estimulação Encefálica Profunda/tendências , Fontes de Energia Elétrica/tendências , Neuroestimuladores Implantáveis/tendências , Doença de Parkinson/terapia , Núcleo Subtalâmico/fisiologia , Adulto , Idoso , Estudos de Coortes , Estimulação Encefálica Profunda/instrumentação , Eletrodos Implantados/tendências , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico , Estudos Retrospectivos
7.
Stereotact Funct Neurosurg ; 97(5-6): 362-368, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31945765

RESUMO

INTRODUCTION: Deep brain stimulation (DBS) for movement disorders has been mainly performed with constant voltage (CV) technology. More recently also constant current (CC) systems have been developed which theoretically might have additional advantages. Furthermore, rechargeable (RC) system implantable pulse generators (IPG) are increasingly being used rather than the former solely available non-rechargeable (NRC) IPGs. OBJECTIVE: To provide a systematic investigation how to proceed and adapt settings when switching from CV NRC to CC RC technology. METHODS: We prospectively collected data from 11 consecutive patients (10 men, mean age at DBS implantation 52.6 ± 14.0 years) with chronic DBS for dystonia (n = 7), Parkinson disease (n = 3), and essential tremor (n = 1) who underwent IPG replacement switching from a CV NRC system (Activa® PC; Medtronic®) to a CC RC system (Vercise® RC; Boston Scientific®). Systematic assessments before and after IPG replacement were performed. RESULTS: DBS technology switching at the time of IPG replacement due to battery depletion was at a mean of 108.5 ± 46.2 months of chronic DBS. No perioperative complications occurred. Clinical outcome was stable with overall mild improvements or deteriorations, which could be dealt with in short-term follow-up. Patients were satisfied with the new RC IPG. CONCLUSIONS: This study confirms both the safety and feasibility of switching between different DBS technologies (CV to CC, NRC to RC, different manufacturers) in patients with chronic DBS. Furthermore, it shows how the management can be planned using available information from the previous DBS settings. Individual assessment is needed and might partly be related to the DBS target and the underlying disease. MR safety might be a problem with such hybrid systems.


Assuntos
Tecnologia Biomédica/métodos , Tecnologia Biomédica/tendências , Estimulação Encefálica Profunda/métodos , Estimulação Encefálica Profunda/tendências , Fontes de Energia Elétrica/tendências , Eletrodos Implantados/tendências , Adulto , Idoso , Tecnologia Biomédica/instrumentação , Estimulação Encefálica Profunda/instrumentação , Distonia/diagnóstico , Distonia/cirurgia , Tremor Essencial/diagnóstico , Tremor Essencial/cirurgia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doença de Parkinson/diagnóstico , Doença de Parkinson/cirurgia , Estudos Prospectivos , Estudos Retrospectivos
8.
Environ Sci Pollut Res Int ; 25(20): 19845-19858, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29737484

RESUMO

The adoption and ratification of relevant policies, particularly the household enrolment system metamorphosis in China, led to rising urbanization growth. As the leading developing economy, China has experienced a drastic and rapid increase in the rate of urbanization, energy use, economic growth and greenhouse gas (GHG) pollution for the past 30 years. The knowledge of the dynamic interrelationships among these trends has a plethora of implications ranging from demographic, energy, and environmental and sustainable development policies. This study analyzes the role of urbanization in decoupling GHG emissions, energy, and income in China while considering the critical contribution of energy use. As a contribution to the extant body of literature, the present research introduces a new phenomenon called "the environmental urbanization Kuznets curve" (EUKC), which shows that at the early stage of urbanization, the environment degrades however, after a threshold point the technique effects surface and environmental degradation reduces with rise in urbanization. Applying the autoregressive distributed lag model and the vector error correction model, the paper finds the presence of inverted U-shaped curve between urbanization and GHG emission of CO2, while the same hypothesis cannot be found between income and GHG emission of CO2. Energy use in all the models contributes to GHG emission of CO2. In decoupling greenhouse gas emissions, urbanization, energy, and income, articulated and well-implemented energy and urbanization policies should be considered.


Assuntos
Dióxido de Carbono/análise , Desenvolvimento Econômico/tendências , Fontes de Energia Elétrica/tendências , Poluição Ambiental/análise , Gases de Efeito Estufa/análise , Renda , Urbanização/tendências , Dióxido de Carbono/economia , China , Desenvolvimento Econômico/estatística & dados numéricos , Fontes de Energia Elétrica/economia , Poluição Ambiental/economia , Efeito Estufa/prevenção & controle , Gases de Efeito Estufa/economia , Renda/estatística & dados numéricos
9.
ChemSusChem ; 10(11): 2352-2359, 2017 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-28409897

RESUMO

By introducing an in situ synthesized low-crystalline ZnO (LC-ZnO) (amorphous) layer between the cathode and the active layer of PCPDTBT:CdSe solar cell {PCPDTBT: poly[2,6-(4,4-bis(2-ethylhexyl)-4H-cyclopenta [2,1-b:3,4-b']dithiophene)-alt-4,7(2,1,3-benzothiadiazole)]}, the device keeps more than 80 and 40 % of its initial lifetime after 180 and 360 days without any encapsulation, respectively. In this regard, 180 days is the highest lifetime achieved for polymer-based solar cells with direct configuration. In addition, the power conversion efficiency (PCE) is improved up to 70 % in the presence of the LC-ZnO interfacial layer. The LC-ZnO layer is synthesized during polymer annealing after solution-deposition of the precursor at a low temperature (140 °C) and a short time. Highly crystalline ZnO (HC-ZnO) nanoparticles are also synthesized and applied as an interfacial layer. The results show that the LC-ZnO is superior to the HC-ZnO in acting as cathode interfacial layer and moisture scavenger because of the high coverage and surface area provided by the in situ synthesis method.


Assuntos
Fontes de Energia Elétrica/tendências , Energia Solar , Óxido de Zinco , Cristalização , Fontes de Energia Elétrica/normas , Eletrodos , Meia-Vida , Polímeros/química
10.
Electrophoresis ; 38(8): 1224-1231, 2017 04.
Artigo em Inglês | MEDLINE | ID: mdl-28078718

RESUMO

Fabric-based microfluidic fuel cells (MFCs) serve as a novel, cost-efficient alternative to traditional FCs and batteries, since fluids naturally travel across fabric via capillary action, eliminating the need for an external pump and lowering production and operation costs. Building on previous research with Y-shaped paper-based MFCs, fabric-based MFCs mitigate fragility and durability issues caused by long periods of fuel immersion. In this study, we describe a microfluidic fabric-based direct formate fuel cell, with 5 M potassium formate and 30% hydrogen peroxide as the anode fuel and cathode oxidant, respectively. Using a two-strip, stacked design, the optimized parameters include the type of encasement, the barrier, and the fabric type. Surface contact of the fabric and laminate sheet expedited flow and respective chemical reactions. The maximum current (22.83 mA/cm2 ) and power (4.40 mW/cm2 ) densities achieved with a 65% cotton/35% polyester blend material are a respective 8.7% and 32% higher than previous studies with Y-shaped paper-based MFCs. In series configuration, the MFCs generate sufficient energy to power a handheld calculator, a thermometer, and a spectrum of light-emitting diodes.


Assuntos
Fontes de Energia Elétrica/tendências , Formiatos , Microfluídica/instrumentação , Têxteis , Fontes de Energia Elétrica/economia , Desenho de Equipamento , Peróxido de Hidrogênio/química , Microfluídica/métodos , Papel
11.
ChemSusChem ; 9(23): 3338-3344, 2016 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-27943666

RESUMO

A novel spatial confinement strategy based on a carbon/TiO2 /carbon sandwich structure is proposed to synthesize TiC nanoparticles anchored on hollow carbon nanospheres (TiC@C) through a carbothermal reduction reaction. During the synthesis process, two carbon layers not only serve as reductant to convert TiO2 into TiC nanoparticles, but also create a spatial confinement to suppress the aggregation of TiO2 , resulting in the formation of well-dispersed TiC nanoparticles. This unique TiC@C structure shows an outstanding long-term cycling stability at high rates owing to the strong physical and chemical adsorption of lithium polysulfides (i.e., a high capacity of 732.6 mA h g-1 at 1600 mA g-1 ) and it retains a capacity of 443.2 mA h g-1 after 1000 cycles, corresponding to a decay rate of only 0.0395 % per cycle. Therefore, this unique TiC@C composite could be considered as an important candidate for the cathode material in Li-S batteries.


Assuntos
Fontes de Energia Elétrica/tendências , Nanopartículas/química , Adsorção , Carbono , Eletrodos , Compostos de Lítio , Nanosferas/química , Sulfetos/química , Titânio
12.
ChemSusChem ; 9(23): 3317-3323, 2016 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-27863048

RESUMO

An all-organic redox flow battery (RFB) employing a fluorescent boron-dipyrromethene (BODIPY) dye (PM567) was investigated. In a RFB, the stability of the electrolyte in all charged states is critically linked to coulombic efficiency. To evaluate stability, bulk electrolysis and cyclic voltammetry (CV) experiments were performed. Oxidized and reduced, PM567 does not remain intact; however, the products of bulk electrolysis evolve over time to show stable redox behavior, making the dye a precursor for the active species of an RFB. A theoretical cell potential of 2.32 V was predicted from CV experiments with a working discharge voltage of approximately 1.6 V in a static test cell. Mass spectrometry was used to identify the products of bulk electrolysis. Related experiments were carried out using ferrocene and cobaltocenium hexafluorophosphate as redox-stable benchmarks to further explain the stability results. The coulombic efficiency of a model cell using PM567 as a precursor for charge carriers stabilized around 73 %.


Assuntos
Compostos de Boro , Fontes de Energia Elétrica/tendências , Eletroquímica/métodos , Eletrólise , Corantes Fluorescentes/química , Oxirredução
13.
ChemSusChem ; 9(23): 3298-3306, 2016 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-27863063

RESUMO

Similar to polymer electrolyte membrane fuel cells, the widespread application of solid acid fuel cells (SAFCs) has been hindered partly by the necessity of the use of the precious-metal catalyst Pt in the electrodes. Here we investigate multi-walled carbon nanotubes (MWCNTs) for their potential catalytic activity by using symmetric cell measurements of solid-acid-based electrochemical cells in a cathodic environment. For all measurements, the carbon nanotubes were Pt free and subject to either nitrogen or oxygen plasma treatment. AC impedance spectroscopy of the electrochemical cells, with and without a DC bias, was performed and showed significantly lower initial impedances for oxygen-plasma-treated MWCNTs compared to those treated with a nitrogen plasma. In symmetric cell measurements with a DC bias, the current declines quickly for oxygen-plasma-treated MWCNTs and more slowly, over 12 days, for nitrogen-plasma-treated MWCNTs. To elucidate the degradation mechanisms of the oxygen-plasma-treated MWCNTs under SAFC operating conditions, theoretical calculations were performed using DFT. The results indicate that several degradation mechanisms are likely to occur in parallel through the reduction of the surface oxygen groups that were introduced by the plasma treatment. This finally leads to an inert MWCNT surface and a very low electrode performance. Nitrogen-plasma-treated MWCNTs appear to have a higher stability and may be worthwhile for future investigations.


Assuntos
Nanotubos de Carbono/química , Nitrogênio/química , Oxigênio/química , Fontes de Energia Elétrica/tendências , Eletroquímica/métodos , Eletrodos
14.
ChemSusChem ; 9(23): 3288-3297, 2016 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-27783456

RESUMO

Formamidinium lead triiodide (FAPbI3 ) is considered as an alternative to methylammonium lead triiodide (MAPbI3 ) because of its lower band gap and better thermal stability. However, owing to the large size of FA cations, it is difficult to synthesize high-quality FAPbI3 thin films without the formation of an undesirable yellow phase. Smaller sized cations, such as MA and Cs, have been successfully used to suppress the formation of the yellow phase. Whereas FA and MA lead triiodide perovskite solar cells (PVSCs) have achieved power conversion efficiencies (PCEs) higher than 20 %, the PCEs of formamidinium and cesium lead triiodide (FA1-x Csx PbI3 ) PVSCs have been only approximately 16.5 %. Herein, we report our examination of the main factors limiting the PCEs of (FA1-x Csx PbI3 ) PVSCs. We find that one of the main limiting factors could be the small grain sizes (≈120 nm), which leads to relatively short carrier lifetimes. We further find that adding a small amount of lead thiocyanate [Pb(SCN)2 ] to the precursors can enlarge the grain size of (FA1-x Csx PbI3 ) perovskite thin films and significantly increase carrier lifetimes. As a result, we are able to fabricate (FA1-x Csx PbI3 ) PVSCs with significantly improved open-circuit voltages and fill factors and, therefore, enhanced PCEs. With an optimal 0.5 mol % Pb(SCN)2 additive, the average PCE is increased from 16.18±0.50 (13.45±0.78) % to 18.16±0.54 (16.86±0.63) % for planar FA0.8 Cs0.2 PbI3 PVSCs if measured under reverse (forward) voltage scans. The champion cell registers a PCE of 19.57 (18.12) % if measured under a reverse (forward) voltage scan, which is comparable to that of the best-performing MA-containing planar FA-based lead halide PVSCs.


Assuntos
Fontes de Energia Elétrica/tendências , Energia Solar , Amidinas/química , Compostos de Cálcio/química , Césio/química , Chumbo , Óxidos/química , Tiocianatos , Titânio/química
15.
ChemSusChem ; 9(21): 3023-3039, 2016 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-27667306

RESUMO

Li-ion and Li-S batteries find enormous applications in different fields, such as electric vehicles and portable electronics. A separator is an indispensable part of the battery design, which functions as a physical barrier for the electrode as well as an electrolyte reservoir for ionic transport. The properties of the separators directly influence the performance of the batteries. Traditional polyolefin separators showed low thermal stability, poor wettability toward the electrolyte, and inadequate barrier properties to polysulfides. To improve the performance and durability of Li-ion and Li-S batteries, development of advanced separators is required. In this review, we summarize recent progress on the fabrication and application of novel separators, including the functionalized polyolefin separator, polymeric separator, and ceramic separator, for Li-ion and Li-S batteries. The characteristics, advantages, and limitations of these separators are discussed. A brief outlook for the future directions of the research in the separators is also provided.


Assuntos
Fontes de Energia Elétrica/tendências , Desenho de Equipamento/tendências , Humanos , Íons , Lítio , Polienos , Enxofre
16.
Europace ; 18(9): 1366-73, 2016 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26847076

RESUMO

AIMS: The longevity of generators is a crucial determinant of the cost-effectiveness of therapy with implantable cardioverter-defibrillators (ICDs) and cardiac resynchronization therapy defibrillators (CRT-D). We evaluated the trend of device-measured residual battery capacity and longevity projections over 5-year follow-up. We also investigated possible factors associated with battery drain. METHODS AND RESULTS: Data from 4851 patients in the European LATITUDE(®) database who were followed up for a minimum of 3 years were analysed. The factors associated with battery drain (i.e. year-to-year decrease in residual battery capacity), and thus potentially impacting on device longevity, were mainly the pacing parameters in CRT-D devices and the number of shocks delivered and diverted in both ICD and CRT-D (all P < 0.01 on linear regression analysis). Over the first 5 years, the longevity estimates provided by devices showed low intra-patient variability and increased with time. The estimates exceeded 10 years for CRT-D and 13 and 12 years for single- and dual-chamber ICDs, respectively. In CRT-D patients, the expected patient age on replacement was 80 ± 12 years, and the expected probability of undergoing device replacement was 63 ± 13% for New York Heart Association (NYHA) II patients and 37 ± 16% for NYHA III patients. For comparison, the probabilities of replacing a CRT-D lasting 5 years were 78 ± 8 and 59 ± 13%, respectively (both P < 0.001). CONCLUSION: Battery drain was mainly associated with pacing output in CRT-D devices and with the number of capacitor charges in both ICD and CRT-D devices. The longevity estimates provided by the devices were consistent and conservative. According to these estimates, among CRT-D recipients a low proportion of patients should require device replacement.


Assuntos
Dispositivos de Terapia de Ressincronização Cardíaca , Terapia de Ressincronização Cardíaca , Desfibriladores Implantáveis , Cardioversão Elétrica/instrumentação , Fontes de Energia Elétrica , Falha de Prótese , Tecnologia de Sensoriamento Remoto , Terapia de Ressincronização Cardíaca/efeitos adversos , Terapia de Ressincronização Cardíaca/tendências , Dispositivos de Terapia de Ressincronização Cardíaca/efeitos adversos , Dispositivos de Terapia de Ressincronização Cardíaca/tendências , Distribuição de Qui-Quadrado , Bases de Dados Factuais , Desfibriladores Implantáveis/efeitos adversos , Desfibriladores Implantáveis/tendências , Remoção de Dispositivo , Cardioversão Elétrica/efeitos adversos , Cardioversão Elétrica/tendências , Fontes de Energia Elétrica/efeitos adversos , Fontes de Energia Elétrica/tendências , Humanos , Modelos Lineares , Desenho de Prótese , Falha de Prótese/tendências , Tecnologia de Sensoriamento Remoto/tendências , Fatores de Risco , Fatores de Tempo , Resultado do Tratamento
17.
Waste Manag ; 49: 427-436, 2016 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-26818182

RESUMO

This paper proposes a forecast of certain rare earth flows in Europe at the 2020 horizon, based on an analysis of trends influencing various actors of the rare earth industry along the value chain. While 2020 is indicated as the forecast horizon, the analysis should be considered as more representative of the next decade. The rare earths considered here are used in applications that are important for a low-carbon energy transition and/or have a significant recycling potential: NdFeB magnets (Pr, Nd, Dy), NiMH batteries (Pr, Nd) and fluorescent lamp phosphors (Eu, Tb, Y). An analysis of major trends affecting the rare earth industry in Europe along the value chain (including extraction, separation, fabrication, manufacture, use and recycling), helps to build a scenario for a material flow analysis of these rare earths in Europe. The scenario assumes in particular that during the next decade, there exists a rare earth mine in production in Europe (with Norra Kärr in Sweden as a most likely candidate) and also that recycling is in line with targets proposed in recent European legislation. Results are presented in the form of Sankey diagrams which help visualize the various flows for the three applications. For example, calculations forecast flows from extraction to separation of Pr, Nd and Dy for magnet applications in Europe, on the order of 310 tons, 980 tons and 80 tons rare earth metal resp., while recycled flows are 35 tons, 110 tons and 30 tons resp. Calculations illustrate how the relative contribution of recycling to supply strongly depends on the situation with respect to demand. Considering the balance between supply and demand, it is not anticipated any significant shortage of rare earth supply in Europe at the 2020 horizon, barring any new geopolitical crisis involving China. For some heavy rare earths, supply will in fact largely outweigh demand, as for example Europium due to the phasing out of fluorescent lights by LEDs.


Assuntos
Fontes de Energia Elétrica , Imãs , Metais Terras Raras/provisão & distribução , Reciclagem , Fontes de Energia Elétrica/tendências , Europa (Continente) , Metais Terras Raras/análise , Reciclagem/tendências
18.
Waste Manag Res ; 33(11): 986-94, 2015 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-26341636

RESUMO

In 2013, more than four million (metric) tons (MT) of refined lead went into batteries in China, and 1.5 MT of scrap lead recycled from these batteries was reused in other secondary materials. The use of start-light-ignition (SLI), traction and energy storage batteries has spread in China in recent decades, with their proportions being 25.6%, 47.2% and 27.2%, respectively, in 2012. The total production of these batteries increased from 296,000 kVAh in 2001 to 205.23 MkVAh in 2013, with manufacturing located mainly in the middle and eastern provinces of the country. In this paper, we find that the market share of SLI batteries will decrease slightly, the share of traction batteries will continuously increase with the emergence of clean energy vehicles, and that of energy storage batteries will increase with the development of the wind energy and photovoltaic industries. Accounting for lead consumption in the main application industries, and the total social possession, it is calculated that used lead batteries could generate 2.4 MT of scrap lead in 2014, which is much higher than the 1.5 MT that was recycled in 2013. Thus, the current recycling rate is too low. It is suggested that while building large-scale recycling plants, small-scale plants should be banned or merged.


Assuntos
Fontes de Energia Elétrica/estatística & dados numéricos , Fontes de Energia Elétrica/tendências , Poluentes Ambientais/análise , Chumbo/análise , Reciclagem , China , Indústrias/estatística & dados numéricos , Indústrias/tendências
19.
Ther Umsch ; 72(8): 529-35, 2015 Aug.
Artigo em Alemão | MEDLINE | ID: mdl-26227982

RESUMO

Cardiac pacemakers are routinely used for the treatment of bradyarrhythmias. Contemporary pacemakers are reliable and allow for a patient specific programming. However, pacemaker replacements due to battery depletion are common (~25 % of all implantation procedures) and bear the risk of complications. Batteryless pacemakers may allow overcoming this limitation. To power a batteryless pacemaker, a mechanism for intracorporeal energy harvesting is required. Such a generator may consist out of subcutaneously implanted solar cells, transforming the small amount of transcutaneously available light into electrical energy. Alternatively, intravascular turbines may harvest energy from the blood flow. Energy may also be harvested from the ventricular wall motion by a dedicated mechanical clockwork converting motion into electrical energy. All these approaches have successfully been tested in vivo. Pacemaker leads constitute another Achilles heel of contemporary pacemakers. Thus, leadless devices are desired. Miniaturized pacemaker circuits and suitable energy harvesting mechanisms (incorporated in a single device) may allow catheter-based implantation of the pacemaker in the heart. Such miniaturized battery- and leadless pacemakers would combine the advantages of both approaches and overcome major limitations of today's systems.


Assuntos
Bradicardia/terapia , Marca-Passo Artificial/tendências , Desenho de Prótese/tendências , Fontes de Energia Elétrica/tendências , Eletrodos Implantados , Previsões , Humanos , Suíça
20.
Waste Manag ; 39: 236-45, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25782361

RESUMO

In this article, a new method based on Material Flow Accounting is proposed to study detailed material flows in battery consumption that can be replicated for other countries. The method uses regularly available statistics on import, industrial production and export of batteries and battery-containing electric and electronic equipment (EEE). To promote method use by other scholars with no access to such data, several empirically results and their trends over time, for different types of batteries occurrence among the EEE types are provided. The information provided by the method can be used to: identify drivers of battery consumption; study the dynamic behavior of battery flows - due to technology development, policies, consumers behavior and infrastructures. The method is exemplified by the study of battery flows in Sweden for years 1996-2013. The batteries were accounted, both in units and weight, as primary and secondary batteries; loose and integrated; by electrochemical composition and share of battery use between different types of EEE. Results show that, despite a fivefold increase in the consumption of rechargeable batteries, they account for only about 14% of total use of portable batteries. Recent increase in digital convergence has resulted in a sharp decline in the consumption of primary batteries, which has now stabilized at a fairly low level. Conversely, the consumption of integrated batteries has increased sharply. In 2013, 61% of the total weight of batteries sold in Sweden was collected, and for the particular case of alkaline manganese dioxide batteries, the value achieved 74%.


Assuntos
Fontes de Energia Elétrica/tendências , Resíduo Eletrônico/análise , Gerenciamento de Resíduos , Suécia
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