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1.
Pharmaceutics ; 15(6)2023 Jun 18.
Artigo em Inglês | MEDLINE | ID: mdl-37376210

RESUMO

The generation and accumulation of an electrostatic charge from handling pharmaceutical powders is a well-known phenomenon, given the insulating nature of most APIs (Active Pharmaceutical Ingredients) and excipients. In capsule-based DPIs (Dry Powder Inhalers), the formulation is stored in a gelatine capsule placed in the inhaler just before inhalation. The action of capsule filling, as well as tumbling or vibration effects during the capsule life cycle, implies a consistent amount of particle-particle and particle-wall contacts. A significant contact-induced electrostatic charging can then take place, potentially affecting the inhaler's efficiency. DEM (Discrete Element Method) simulations were performed on a carrier-based DPI formulation (salbutamol-lactose) to evaluate such effects. After performing a comparison with the experimental data on a carrier-only system under similar conditions, a detailed analysis was conducted on two carrier-API configurations with different API loadings per carrier particle. The charge acquired by the two solid phases was tracked in both the initial particle settling and the capsule shaking process. Alternating positive-negative charging was observed. Particle charging was then investigated in relation to the collision statistics, tracking the particle-particle and particle-wall events for the carrier and API. Finally, an analysis of the relative importance of electrostatic, cohesive/adhesive, and inertial forces allowed the importance of each term in determining the trajectory of the powder particles to be estimated.

2.
Waste Manag ; 155: 311-319, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36410148

RESUMO

Meeting the current demand for concrete requires not only mining tons of gravel and sand, but also burning large amounts of fossil fuel resources in cement kilning. Consequently, concrete recycling is crucial to achieving a material-efficient society, especially with the application of various categories of concrete and the goal of phasing out fossil fuels. A comparative life cycle assessment (LCA) is used to assess the engineering material footprint (EMF) and the fossil fuel material footprint (FMF) in closed-loop recycling of three types of concrete: siliceous concrete, limestone concrete, and lightweight aggregate concrete. This study aims to investigate the impact of (i) concrete categories, (ii) methods to model recycling, and (iii) using renewable energy sources on the material footprint in concrete recycling. The results highlight that the concrete recycling system can reduce 99% of the EMF and 66-93% of the FMF compared with the baseline system, in which concrete waste is landfilled. All three recycling modeling approaches indicate that concrete recycling can considerably reduce EMF and FMF compared with the baseline system, primarily resulting from the displacement of virgin raw materials. Using alternative diesels is more sensitive than adopting renewable electricity in reduction of the FMF in concrete recycling. Replacing diesel with electrolysis- and coal-based synthetic diesel for concrete recycling could even increase the FMF, while using biodiesel made from rapeseed and wood-based synthetic diesel can reduce 47-51% and 84-89% of the FMF, respectively, compared to the virgin diesel-based recycling system. Finally, we discussed the multifunctionality and rebound effects of recycling, and double-counting risk in material and energy accounting.


Assuntos
Combustíveis Fósseis , Reciclagem , Animais , Biocombustíveis , Carbonato de Cálcio , Estágios do Ciclo de Vida
3.
Sci Total Environ ; 803: 149892, 2022 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-34500281

RESUMO

The construction sector is the biggest driver of resource consumption and waste generation in Europe. The European Union (EU) is making efforts to move from its traditional linear resource and waste management system in the construction sector to a level of high circularity. Based on the theory of circular economy, a new paradigm called waste hierarchy was introduced in the EU Waste Framework Directive. This work uses the framework of the waste hierarchy to analyze the practice of construction and demolition waste (CDW) management in Europe. We explore the evolution of the waste hierarchy in Europe and how it compares with the circular economy. Then, based on the framework, we analyze the performance of CDW management in each EU member state. Innovative treatment methods of CDW, focusing on waste concrete, is investigated. This brings insight into optimizing and upgrading the CDW management in light of advanced technologies and steering the pathway for transitioning the EU towards a circular society.


Assuntos
Indústria da Construção , Gerenciamento de Resíduos , Materiais de Construção , Europa (Continente) , Resíduos Industriais/análise , Reciclagem
4.
Waste Manag ; 121: 33-41, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33341692

RESUMO

Bottom ash contains unfavorable contaminants that could leach into the circulating water used for wet treatment, and its improper disposal of bottom ash could cause ecological pollution. This study was to discuss the partition of heavy metals and salts of bottom ash into circulating water and ash stockpile runoff in wet treatment plants in southern China. The leachability of bottom ash before and after the wet treatment was also investigated. The checked heavy metals Pb, Cu, and Ni and dissolved salts Cl- and SO42- show lower available fractions in leachate from the treated bottom ash than that in raw bottom ash. Circulating water is contaminated by target heavy metals, which the contents of Cu and Pb is higher than its limit for urban wastewater discharge. The circulating water owned the highest concentration of Cl- and SO42-, above10000 mg/L, and 1100 mg/L, which is far higher than the limits. The detected heavy metals, Cl- and SO42- in runoff also exceed the limits for urban wastewater discharge. Locations for bottom ash processing and storage sites should be selected to control and prevent any leaching and runoff impacts. Any runoff and circulation water should be discharged to the lined landfill's leachate collection system or suitable industrial wastewater treatment facilities.


Assuntos
Metais Pesados , Eliminação de Resíduos , China , Cinza de Carvão , Incineração , Metais Pesados/análise , Sais , Resíduos Sólidos/análise
5.
BMC Anesthesiol ; 20(1): 122, 2020 05 23.
Artigo em Inglês | MEDLINE | ID: mdl-32446301

RESUMO

BACKGROUND: The use of Spinal Cord Stimulation (SCS) system to treat medically refractory neuropathic pain is increasing. Severe neuropathic pain can be found in giant chest wall arteriovenous malformations (AVMs), exceedingly rare and debilitating abnormalities, rarely reported during pregnancy. CASE PRESENTATION: We present a report of a pregnant patient with implanted Spinal Cord Stimulation (SCS) system because of painful thoracic AVM scheduled for an urgent cesarean section in which we used lumbar ultrasound (US) to rule out the possibility to damage SCS electrodes and to find a safe site to perform spinal anesthesia. CONCLUSIONS: The use of lumbar US to find a safe site for a lumbar puncture in presence of SCS system in a patient affected by painful thoracic AVM makes this case a particularly unique operative challenge and offers a new possible use of ultrasound to detect a safe space in patients with SCS implant.


Assuntos
Anestesia Obstétrica/métodos , Raquianestesia/métodos , Malformações Arteriovenosas/terapia , Complicações Cardiovasculares na Gravidez/terapia , Estimulação da Medula Espinal , Adulto , Cesárea , Feminino , Humanos , Gravidez , Parede Torácica/irrigação sanguínea , Ultrassonografia
6.
J Hazard Mater ; 389: 122045, 2020 05 05.
Artigo em Inglês | MEDLINE | ID: mdl-32000122

RESUMO

This study investigated the presence and concentration of 16 U.S. EPA priority controlled PAHs in gas, bio-oil and residues from the pyrolysis of different sewage sludges. We studied the temperature as a key influential factor for the formation of 16 targets PAHs and the effect of sludge source on the distribution of different molecules' PAHs were analyzed. Results showed that most of the 16 PAHs were formed during sludge pyrolysis and mainly ended up in bio-oil and gas. The distribution of PAHs in bio-oil was mostly dependent on pyrolysis temperature. With the increase of pyrolysis temperature from 450℃ to 850℃, it has been observed an increase of PAHs concentration in the bio-oils as follows: 16 % (ISS), 1.3 % (food manufacture wastewater sludge, FSS), 194 % (printing and dyeing wastewater sludge, PDSS), 334 % (DSS). 2, 3 and 4-ring PAHs dominate, and their total mass proportion is over 70 %. In gas, the types and concentrations of PAHs were less than in bio-oil. PAHs yield in solid was very low, and a trace content of PAHs of 0.0161 mg kg-1 was detected from the solid after the pyrolysis of DSS, while PAHs in solid for ISS and FSS are even non-existent and would cause fewer environmental problems.


Assuntos
Poluentes Ambientais/análise , Hidrocarbonetos Policíclicos Aromáticos/análise , Esgotos/análise , Poluentes Ambientais/química , Gases/análise , Gases/química , Temperatura Alta , Óleos/análise , Óleos/química , Hidrocarbonetos Policíclicos Aromáticos/química , Pirólise , Esgotos/química
7.
Risk Anal ; 39(12): 2766-2785, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31361041

RESUMO

Defenders have to enforce defense strategies by taking decisions on allocation of resources to protect the integrity and survivability of cyber-physical systems (CPSs) from intentional and malicious cyber attacks. In this work, we propose an adversarial risk analysis approach to provide a novel one-sided prescriptive support strategy for the defender to optimize the defensive resource allocation, based on a subjective expected utility model, in which the decisions of the adversaries are uncertain. This increases confidence in cyber security through robustness of CPS protection actions against uncertain malicious threats compared with prescriptions provided by a classical defend-attack game-theoretical approach. We present the approach and the results of its application to a nuclear CPS, specifically the digital instrumentation and control system of the advanced lead-cooled fast reactor European demonstrator.

8.
Waste Manag ; 60: 50-55, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-27353391

RESUMO

Plastic polymers are characterized by a high calorific value. Post-consumer plastic waste can be thus considered, in many cases, as a typical secondary solid fuels according to the European Commission directive on End of Waste (EoW). In Europe the practice of incineration is considered one of the solutions for waste disposal waste, for energy recovery and, as a consequence, for the reduction of waste sent to landfill. A full characterization of these products represents the first step to profitably and correctly utilize them. Several techniques have been investigated in this paper in order to separate and characterize post-consumer plastic packaging waste fulfilling the previous goals, that is: gravity separation (i.e. Reflux Classifier), FT-IR spectroscopy, NIR HyperSpectralImaging (HSI) based techniques and calorimetric test. The study demonstrated as the proposed separation technique and the HyperSpectral NIR Imaging approach allow to separate and recognize the different polymers (i.e. PolyVinyl Chloride (PVC), PolyStyrene (PS), PolyEthylene (PE), PoliEtilene Tereftalato (PET), PolyPropylene (PP)) in order to maximize the removal of the PVC fraction from plastic waste and to perform the full quality control of the resulting products, can be profitably utilized to set up analytical/control strategies finalized to obtain a low content of PVC in the final Solid Recovered Fuel (SRF), thus enhancing SRF quality, increasing its value and reducing the "final waste".


Assuntos
Cloreto de Polivinila/análise , Reciclagem/métodos , Resíduos Sólidos/análise , Gerenciamento de Resíduos/métodos , Calorimetria , Gravitação , Embalagem de Produtos , Eliminação de Resíduos , Espectroscopia de Infravermelho com Transformada de Fourier
9.
Risk Anal ; 35(1): 142-56, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25041408

RESUMO

Dynamic reliability methods aim at complementing the capability of traditional static approaches (e.g., event trees [ETs] and fault trees [FTs]) by accounting for the system dynamic behavior and its interactions with the system state transition process. For this, the system dynamics is here described by a time-dependent model that includes the dependencies with the stochastic transition events. In this article, we present a novel computational framework for dynamic reliability analysis whose objectives are i) accounting for discrete stochastic transition events and ii) identifying the prime implicants (PIs) of the dynamic system. The framework entails adopting a multiple-valued logic (MVL) to consider stochastic transitions at discretized times. Then, PIs are originally identified by a differential evolution (DE) algorithm that looks for the optimal MVL solution of a covering problem formulated for MVL accident scenarios. For testing the feasibility of the framework, a dynamic noncoherent system composed of five components that can fail at discretized times has been analyzed, showing the applicability of the framework to practical cases.

10.
Waste Manag ; 33(3): 574-84, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23273624

RESUMO

Packaging waste is one of the main sources of secondary polyolefins. It is essential to characterize polyolefins derived from this waste stream in such way, that not only mechanical sorting methods can effectively separate, but also that on-line sensor systems can quantitatively assess their distribution. The characterization methodology is hierarchical, relating all properties of waste particles in any phase of the processing ultimately to the input End-Of-Life products. The present paper documents a pre-concentrate obtained by hand picking of mixed Romanian household waste. Investigations have been addressed to identify the composition of this polyolefin waste stream, to study the polyolefin density distribution, to distinguish the polymer manufacturing methods (i.e. injection molding and blow molding) by flake physical properties and finally to perform all the required characterization and identification by hyperspectral imaging. On the basis of these analyses, polyolefins from packaging wastes can be recycled by density separation and their rheological properties and wall thickness indicate the molding procedures. Hyperspectral imaging based procedures have been also applied to set up quality control actions for recycled products.


Assuntos
Polienos , Embalagem de Produtos , Reciclagem/métodos , Produtos Domésticos , Polienos/análise , Polienos/química , Eliminação de Resíduos/métodos , Reologia , Romênia
11.
Kidney Int ; 62(6): 2126-35, 2002 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-12427137

RESUMO

BACKGROUND: The bulk of bicarbonate reabsorption along the loop of Henle (LOH) is localized at the level of the thick ascending limb (TAL) and is mainly dependent on the presence of luminal Na+-H+ exchanger (NHE-3). We investigated whether the reduction of renal mass is associated with alterations in LOH bicarbonate transport coupled to changes in NHE-3 gene expression and in vivo activity. METHODS: Sham-operated and remnant rats (4/6 nephrectomy) were studied 15 days after the surgery. To measure net bicarbonate reabsorption (JHCO3-) superficial loops were perfused by in vivo micropuncture. Perfusate was an end-like proximal solution containing 3H-methoxy-inulin. NHE-3 gene expression was quantified by competitive PCR using an internal standard of cDNA that differed from the wild-type NHE-3 by a deletion of 76 bp. Western blot experiments were performed on TAL suspension using anti-NHE-3 antibodies. RESULTS: At various LOH bicarbonate loads, JHCO3- was constantly larger in remnant rats as compared to sham-operated animals. NHE-3 mRNA abundance was estimated to be 0.339 +/- 0.031 attomoles (amol)/ng-1 total RNA in sham-operated (N = 5) and it increased to 0.465 +/- 0.023 in remnant rats (N = 5, P < 0.01). Western blot experiments showed a significant increase of NHE-3 protein abundance in TAL of remnant rats as compared to sham-operated animals. Finally, by means of a specific NHE-3 inhibitor, S-3226, in vivo microperfusion experiments demonstrated that NHE-3 in vivo activity along the LOH was substantially increased in remnant rats in addition to the non-NHE-3 bicarbonate transport. CONCLUSIONS: These data indicate that the reduction of renal mass increases mRNA, protein abundance and in vivo activity of NHE-3 along the TAL. This may explain, at least in part, the augmented transepithelial bicarbonate transport along the LOH. Such an effect will counterbalance the increased glomerular bicarbonate load, thus preventing urinary bicarbonate loss and mitigating the ensuing metabolic acidosis.


Assuntos
Acidose/metabolismo , Alcalose/metabolismo , Bicarbonatos/urina , Alça do Néfron/metabolismo , Trocadores de Sódio-Hidrogênio/genética , Trocadores de Sódio-Hidrogênio/metabolismo , Equilíbrio Ácido-Base/fisiologia , Animais , Western Blotting , Expressão Gênica/fisiologia , Guanidinas/farmacologia , Masculino , Metacrilatos/farmacologia , Nefrectomia , Reação em Cadeia da Polimerase , Ratos , Ratos Sprague-Dawley , Circulação Renal/fisiologia , Trocador 3 de Sódio-Hidrogênio , Trocadores de Sódio-Hidrogênio/antagonistas & inibidores
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