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1.
Heliyon ; 10(7): e28980, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38633643

RESUMO

Solid waste management is one of the biggest challenges of the current era. The combustible fractions in the waste stream turn out to be a good energy source if converted into refuse-derived fuel. Researchers worldwide are successfully converting it into fuel. However, certain challenges are associated with its application in gasifiers, boilers, etc. to co-fire it with coal. These include high moisture content, low calorific value, and difficulty to transport and store. The present study proposed torrefaction as a pretreatment of the waste by heating it in the range of 200 °C-300 °C in the absence of oxygen at atmospheric pressure. The combustible fraction from the waste stream consisting of wood, textile, paper, carton, and plastics termed as mixed waste was collected and torrefied at 225 °C, 250 °C, 275 °C, and 300 °C for 15 and 30 min each. It was observed that the mass yield and energy yield decreased to 45% and 62.96% respectively, but the energy yield tended to increase by the ratio of 1.39. Proximate analysis showed that the moisture content and volatile matter decreased for torrefied samples, whereas the ash content and fixed carbon content increased. Similarly, the elemental analysis revealed that the carbon content increased around 23% compared to raw samples with torrefaction contrary to hydrogen and oxygen, which decreased. Moreover, the higher heating value (HHV) of the torrefied samples increased around 1.3 times as compared to the raw sample. This pretreatment can serve as an effective solution to the current challenges and enhance refuse-derived fuel's fuel properties.

2.
Heliyon ; 10(5): e27185, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38495186

RESUMO

The present study investigates the MHD electro-osmotic flow of entropy generation analysis for peristaltic movement in a nanofluid with temperature-dependent viscosity. Long wavelengths, i.e., The magnitude of a wave's energy corresponds directly to its frequency while being inversely related to its wavelength in terms of velocity, temperature, and concentration, govern and confine the flow stream in the laminar region. Ohmic heating and hall effects are also included. Graphs are used to obtain and examine numerical solutions for axial velocity, temperature, concentration, Bejan number, and entropy generation. The effects of this research can help to improve pumping and gastrointestinal movements in different engineering devices. Debye-Huckel and lubrication approximations are studied to access the Boltzmann distribution of electric potential across an electric double layer. The investigations of an existing model are important in illuminating the microfluidics machinery used at the micro level for various transport phenomena in which fluids as well as particles are transported together. The current study has many applications and can be further extended to a three-dimensional profile with appropriate modifications and assumptions. When studying entropy generation, it is essential to examine the irreversible factors, while also taking into account the velocity and thermal slip conditions at channel boundaries. Moreover, the concept of entropy generation holds significant importance in comprehending various biological phenomena. Hence, the current research holds promising implications for both industrial and medical fields. The entropy generation is minimum at left wall of the channel for negative values of Helmholtz-Smoluchowski velocity.

3.
Heliyon ; 10(5): e26395, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38439869

RESUMO

It is precarious to scrutinize the impacts of operational parameters on corrosion when choosing materials for the green diesel and automotive industries. This was the original study to showcase an optimization stratagem for abating corrosion rates (CRs) of automotive parts (APs) explicitly copper and brass in a biodiesel environment, adopting novel Response Surface Methodology (RSM) and Adaptive Neuro-Fuzzy Inference System (ANFIS).To model CRs, the RSM and ANFIS were utilized. The mechanical properties of APs were inspected, explicitly their hardness number and tensile strength, as well as their outward morphologies. The optimal CRs for copper and brass were 0.01656 mpy and 0.008189 mpy at a B 3.91 biodiesel/diesel blend and 240.9-h exposure. The ANFIS model had a higher coefficient of determination and lower values of root mean squared errors (RMSE), mean average error (MAE), and average absolute deviation (AAD) when compared to the RSM model; this authenticates the ANFIS model's superiority for predicting CRs of copper and brass. The tensile strength of brass was greater than that of copper, while the latter had a higher hardness number. The information, model, and correlations can assist APS in mitigating and slaving over for the corrosiveness of APs while utilizing green diesel.

4.
Heliyon ; 10(4): e26493, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38440295

RESUMO

The present experimental study investigates the thermal and hydraulic performance of Ethylene Glycol (EG)-based ZnO nanofluids (NFs) in circular minichannel test sections, each of 330 mm in length and 1.0-2.0 mm inner diameters. The experiments were conducted under steady-state constant heat flux and laminar flow conditions. The stable ZnO/EG-based NFs were synthesized using a standard two-step method in varying nanoparticles (NPs) loadings (0.012-0.048 wt%). The morphological characteristics, crystal structure, and specific surface area (SSA) showed that the NPs were sized in nm, possessing excellent crystal structure and enhanced surface area. Thermal conductivity (TC) and viscosity (VC) of the NFs were examined in the 20-60 °C temperature range. Both TC and VC possessed an increasing trend with the rise in concentration of the NPs. However, with the temperature rise, TC increased while the VC decreased and vice versa. The highest enhancements in TC and VC were 14.38 % and 15.22 %, respectively, at 40 °C and 0.048 wt% of NPs loading. The highest enrichment recorded in the local and average heat transfer coefficient (HTC) were 14.80 % and 13.48% in a minichannel with 1.0 mm inner diameter, respectively. It was directly proportional to the NPs loading and volume flow rate of the NFs. The friction factor was also directly proportional to the test section's inner cross-sectional area, while the pressure gradient showed an inverse behavior. An inverse relationship was recorded for the volume flow rate of the NFs and vice versa. Maximum friction factor and the pressure drop for all three minichannel test sections were recorded as 34.58 % and 32.16 %, respectively. The well-known Shah correlation predicted the local and average HTC within ±15.0 %, while the friction factor and the pressure gradient were well predicted by the Darcy correlation within the ±10.0 % range.

5.
Heliyon ; 10(4): e26396, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38404828

RESUMO

Hybrid nanofluids (HNFs) of metallic oxide-based nanoparticles (NPs) have been prepared in different basefluids (BFs) employing the thermal plasma technique. NPs of ZnO-MgO were directly dispersed into pristine coolant, engine oil, distilled water (DW), and coconut oil. Plasma was generated between two identical electrodes applying 8.0 kV at the ambient conditions and proved economically viable in preparing stable HNFs. X-ray Diffractometry (XRD) showed ZnO and MgO NPs possessed hexagonal and cubic crystal structures, respectively. The band gap is calculated through UV-visible spectroscopy. The thermal conductivity (TC) of the HNFs has been measured using a thermal conductivity analyzer based on the transient hot wire method. The band gaps of pristine coolant and its HNFs were obtained to be 3.35 eV and 3.33 eV, respectively. In engine oil and its HNFs, band gaps of 3.16 eV and 3.02 eV have been extracted. There appears to be a slight reduction in band gap for coolant and engine oil-based HNFs. The band gap value of coconut oil-based HNFs was 4.05 eV, which showed a higher value than the pristine coconut oil-based HNFs (3.95 eV). The band gap calculated in the case of DW-based HNFs was 3.79 eV. TC of HNFs with volume concentration of 0.019 % for DW, 0.020 % for coolant, 0.016 % for engine oil, and 0.017 % for coconut oil were tested between 20 and 60 °C. An increase in TC was observed with the rise in temperature of the HNFs. Maximum increment in TC was observed at 60 °C for coolant-based HNFs, which was 19 %, followed by DW (18%), coconut oil (18%), and engine oil (16%), respectively. DW-based HNFs can be used as a coolant and optical filter for optoelectronics devices like photovoltaic cells for better performance. The study underscores precise control of NPs size as pivotal for band gap influence. HNFs hold promise as the next-gen heat transfer fluids (HTFs), revolutionizing thermal conductivity across industries. This research lays a firm foundation for plasma-synthesized HNFs' application in enhanced heat transfer and optoelectronic devices. Coolant-based HNFs excel in thermal conductivity, addressing heat transfer challenges.

6.
Heliyon ; 10(4): e25788, 2024 Feb 29.
Artigo em Inglês | MEDLINE | ID: mdl-38404874

RESUMO

Due to increasing urbanization and population growth, municipal solid waste management (MSWM) is a significant environmental concern in developing countries. Inadequate waste management systems lead to environmental pollution, health hazards, and economic losses. While considering the challenges and limitations, policymakers and authorities need to opt for such waste management scenarios that are environmentally friendly and resolve energy issues. Ten MSWM scenarios were developed and evaluated using seven different criteria. Four multi-criteria decision-making (MCDM) techniques, namely fuzzy logic, AHP, TOPSIS, and PROMETHEE II, were employed to rank the scenarios and identify the most appropriate option for solid waste management in Lahore. This study highlights that the optimal waste management approach comprises a composition of 54% anaerobic digestion, 37% gasification, and 9% landfill technologies. These percentages collectively represent the most suitable and effective strategies for the city's waste management needs. All the MCDM techniques consistently produce similar results. These scenarios have broader applicability across cities in Central Asia and beyond. The study's findings are aligned to promote sustainable and environmentally friendly MSWM practices. These findings endorse implementing strategies and measures aimed at fostering environmental sustainability and the responsible handling of waste, serving as a valuable reference for various regions.

7.
Heliyon ; 10(3): e25419, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38333824

RESUMO

Carbon capture, utilization and storage (CCUS) technologies are utmost need of the modern era. CCUS technologies adoption is compulsory to keep global warming below 1.5 °C. Mineral carbonation (MC) is considered one of the safest and most viable methods to sequester anthropogenic carbon dioxide (CO2). MC is an exothermic reaction and occur naturally in the subsurface because of fluid-rock interactions with serpentinite. In serpentine carbonation, CO2 reacts with magnesium to produce carbonates. This article covers CO2 mitigation technologies especially mineral carbonation, mineral carbonation by natural and industrial materials, mineral carbonation feedstock availability in Pakistan, detailed characterization of serpentine from Skardu serpentinite belt, geo sequestration, oceanic sequestration, CO2 to urea and CO2 to methanol and other chemicals. Advantages, disadvantages, and suitability of these technologies is discussed. These technologies are utmost necessary for Pakistan as recent climate change induced flooding devastated one third of Pakistan affecting millions of families. Hence, Pakistan must store CO2 through various CCUS technologies.

8.
Heliyon ; 9(11): e22404, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38074886

RESUMO

The carbon footprint (CFP) is a measure of greenhouse gases (GHGs) emitted throughout the lifecycle of a product or activity, while the energy footprint (EFP) and water footprint (WFP) measure energy and water consumption, respectively. These footprints are essential for managing emissions and consumption and promoting low-carbon consumption. A carbon labeling scheme could help consumers make informed choices. Asia is a major textile producer and consumer, so studying textiles' carbon, energy, and water footprints is essential for managing domestic emissions, energy and water consumption, and international trade negotiations. This paper presents a method and framework for assessing CFP, EFP, and WFP at the product level and calculates the footprints for textile products. The results show that the total CFP of all textile products produced is 42,624.12 MT CO2e, with indirect emissions contributing significantly more than direct emissions. The total EFP is 248.38 PJ, with electricity consumption being the main contributor, while the total WFP is 80.71 billion liters. The spinning stage of production has the highest CFP and EFP, and energy consumption is the main contributor to all footprints. These results can help compare different products and reduce the footprints of the textile sector.

9.
Heliyon ; 9(11): e21796, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38027886

RESUMO

Mineral technology has attracted significant attention in recent decades. Mineral carbonation technology is being used for permanent sequestration of CO2 (greenhouse gas). Temperature programmed desorption studies showed interaction of CO2 with Mg indicating possibility of using natural feedstocks for mineral carbonation. Soaking is effective to increase yields of heat-activated materials. This review covers the latest developments in mineral carbonation technology. In this review, development in carbonation of natural minerals, effect of soaking on raw and heat-activated dunite, increasing reactivity of minerals, thermal activation, carbonations of waste materials, increasing efficiency of carbonation process and pilot plants on mineral carbonation are discussed. Developments in carbonation processes (single-stage carbonation, two-stage carbonation, acid dissolution, ph swing process) and pre-process and concurrent grinding are elaborated. This review also highlights future research required in mineral carbonation technology.

10.
Heliyon ; 9(10): e21133, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37916073

RESUMO

Ecosystem degradation and fossil fuel depletion are the two foremost concerns to look for alternative fuels. Rapid population growth is primarily accountable for higher consumption of fossil fuel sources, although engine technology is achieving milestones in terms of fuel efficiency and lower exhaust emissions in order to contribute towards a sustainable environment. The main root cause of global warming is carbon dioxide emissions; therefore, it is imperative to assess the impact of alternative fuels in diesel engines with an aim to minimize carbon emissions. A current study deals with the reduction of carbon emissions and improvement of efficiency through addition of manganese nano-additive to di-ethyl ether and diesel fuel blend in particulate form. Fuel blends were formed by adding various proportions of manganese to high-speed diesel fuel and stirring the mixture while heating it for 10 min. The blends were then tested in diesel engines at two distinct loads and five engine speed ranges. Emission analyzer was used to ascertain the CO2 output of engine. At higher loads for 10 % diethyl ether in diesel, the increase in brake thermal efficiency was 24.19, 28.17 and 26.86 % when the manganese amount in blend was changed as 250 mg, 375 mg and 500 mg respectively. On the other side CO2 emissions increase by 11.57, 30.52 and 20.33 % for manganese concentrations of 250 mg, 375 mg and 500 mg respectively. Analysis performed with Design Expert 13 showed that the desirability was 0.796 for a blend of 375 mg manganese at 1300 rpm and 4500 W load with 33.0611 % BTE, 334.011kg/kWh BSFC, 67.8821Nm torque, and 6.072 % CO2. Therefore, it can be deduced that manganese nanoparticle blends improved engine performance but CO2 emissions also increase which can be responsible for global warming and it should be reduced through catalytic converters.

11.
Heliyon ; 9(11): e22028, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-38034731

RESUMO

This study was based on the experimental performance evaluation of a wood polymer composite (WPC) that was synthesized by incorporating untreated and treated rice husk (RH) fibers into a polypropylene random copolymer matrix. The submicron-scale RH fibers were alkali-treated to modify the surface and introduce new functional groups in the WPC. A compatibilizer (maleic anhydride) and a thermos-mechanical properties modifier (polypropylene grafted with 30 % glass fiber) were used in the WPC. The effects of untreated and treated RH on the WPC panels were studied using FESEM, FTIR, and microscope images. A pin-on-disk setup was used to investigate the bulk tribological properties of PPRC and WPC. The complex relationship between the friction coefficient of different loading of RH fibers in the WPC, as a function of sliding distance, was analyzed along with the temperature and morphology of the surface. It was observed that untreated RH acted as a friction modifier, while treated RH acted as a solid lubricant. Microhardness was calculated using the QCSM module on nanoindentation. It was found that untreated RH led to an increase in microhardness, while treated RH caused a decrease in hardness compared to PPRC.

12.
Heliyon ; 9(7): e17758, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37539290

RESUMO

For a few decades now fast depleting fossil fuels has been a major challenge. Fast expanding population and increased rate of urbanization has increased energy demand. This makes the current scenario worse. Fossil fuels' emissions are another challenge. Apart from fossil fuel emissions, the untreated disposal of waste cooking oil presents another environment's sustainability challenge. The treatment of waste cooking oil as fuel presents a tangible solution to challenge. In this research article, impact of the engine speed and the concentration of titanium dioxide (TiO2) nanoparticles (NPs) in diesel-biodiesel blended fuels on the engine's performance. The emission characteristics of a single-cylinder four-stroke diesel engine has also been examined. TiO2 NPs were produced by a sol-gel methodology. The diesel-biodiesel combination was fortified with TiO2 NPs at 40, 80 and 120 ppm. These mixtures were used to power the diesel engine, which was then run at 1150, 1400, 1650, 1900 and 2150 RPM. Interaction between engine speeds and nanoparticle concentrations and investigation of their combined effect on engine performance and emissions was done using response surface methodology. The minimum BSFC of 0.33994 kg/kWh and maximum BTE of 25.90% were found for B30 + 120 ppm biodiesel blend at 2150 rpm as compared to all other tested fuels. The emissions including CO and HC emissions were recorded as 25.61486 kg/kWh and 0.05289kg/kWh respectively at 2150 rpm for B30 + 120 ppm biodiesel blend while NOx on the contrary side exhibits a slight escalation with increasing engine speed and nanoparticles concentration. The findings of the experiments demonstrated that adding TiO2 nanoparticles to diesel-biodiesel blends is an effective way to enhance the performance of diesel engines while simultaneously reducing the emissions. It was also discovered that the mathematical model that was built can efficiently estimate the performance of the engine and the emission levels.

13.
Environ Pollut ; 326: 121474, 2023 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-36965686

RESUMO

Recently, solar photovoltaic (PV) technology has shown tremendous growth among all renewable energy sectors. The attractiveness of a PV system depends deeply of the module and it is primarily determined by its performance. The quantity of electricity and power generated by a PV cell is contingent upon a number of parameters that can be intrinsic to the PV system itself, external or environmental. Thus, to improve the PV panel performance and lifetime, it is crucial to recognize the main parameters that directly influence the module during its operational lifetime. Among these parameters there are numerous factors that positively impact a PV system including the temperature of the solar panel, humidity, wind speed, amount of light, altitude and barometric pressure. On the other hand, the module can be exposed to simultaneous environmental stresses such as dust accumulation, shading and pollution factors. All these factors can gradually decrease the performance of the PV panel. This review not only provides the factors impacting PV panel's performance but also discusses the degradation and failure parameters that can usually affect the PV technology. The major points include: 1) Total quantity of energy extracted from a photovoltaic module is impacted on a daily, quarterly, seasonal, and yearly scale by the amount of dust formed on the surface of the module. 2) Climatic conditions as high temperatures and relative humidity affect the operation of solar cells by more than 70% and lead to a considerable decrease in solar cells efficiency. 3) The PV module current can be affected by soft shading while the voltage does not vary. In the case of hard shadowing, the performance of the photovoltaic module is determined by whether some or all of the cells of the module are shaded. 4) Compared to more traditional forms of energy production, PV systems offer a significant number of advantages to the environment. Nevertheless, these systems can procure greenhouse gas emissions, especially during the production stages. In conclusion, this study underlines the importance of considering multiple parameters while evaluating the performance of photovoltaic modules. Environmental factors can have a major impact on the performance of a PV system. It is critical to consider these factors, as well as intrinsic and other intermediate factors, to optimize the performance of solar energy systems. In addition, continuous monitoring and maintenance of PV systems is essential to ensure maximum efficiency and performance.


Assuntos
Gases de Efeito Estufa , Energia Solar , Poeira/análise , Umidade
14.
Waste Manag ; 156: 1-11, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36424243

RESUMO

The integration of hydrogen in the primary energy mix requires a major technological shift in virtually every energy-related application. This study has attempted to investigate the techno-economic solar photovoltaic (PV) integrated water electrolysis and waste incineration system. Three different strategies, i.e., (i) PV + Battery(Hybrid mode with required batteries); (ii) auto-ignition (Direct coupling); and (iii) PV + Secondary-Electrolyzer(Direct coupling assisted with secondary electrolyzer), have been envisioned. The 'PV + Battery' consume 42.42 % and 15.07 % less energy than the auto-ignition and 'PV + Secondary-Electrolyzer' methods. However, the capital cost of 'PV + Battery' has been calculated to be 15.4 % and 11.8 % more than auto-ignition and 'PV + Secondary-Electrolyzer, respectively.The energy consumption relative to waste input, the 'PV + Battery' method used 80 % less energy, while auto-ignition and 'PV + Secondary-Electrolyzer' showed 70.5 % and 77.5 % less energy, respectively. Furthermore, these approaches showed a vast difference in cost-benefit for the longer run. 'PV + Battery' was forecasted to be 73.3 % and 23.3 % more expensive than auto-ignition and 'PV + Secondary-Electrolyzer' methods, respectively, for 30 years. Overall, this study can benefit from using either of these methods depending on the application, usage scale, and climatic conditions.


Assuntos
Hidrogênio , Incineração , Fontes de Energia Elétrica
15.
Arch Comput Methods Eng ; 29(1): 129-194, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33935484

RESUMO

Covid-19 has given one positive perspective to look at our planet earth in terms of reducing the air and noise pollution thus improving the environmental conditions globally. This positive outcome of pandemic has given the indication that the future of energy belong to green energy and one of the emerging source of green energy is Lithium-ion batteries (LIBs). LIBs are the backbone of the electric vehicles but there are some major issues faced by the them like poor thermal performance, thermal runaway, fire hazards and faster rate of discharge under low and high temperature environment,. Therefore to overcome these problems most of the researchers have come up with new methods of controlling and maintaining the overall thermal performance of the LIBs. The present review paper mainly is focused on optimization of thermal and structural design parameters of the LIBs under different BTMSs. The optimized BTMS generally demonstrated in this paper are maximum temperature of battery cell, battery pack or battery module, temperature uniformity, maximum or average temperature difference, inlet temperature of coolant, flow velocity, and pressure drop. Whereas the major structural design optimization parameters highlighted in this paper are type of flow channel, number of channels, length of channel, diameter of channel, cell to cell spacing, inlet and outlet plenum angle and arrangement of channels. These optimized parameters investigated under different BTMS heads such as air, PCM (phase change material), mini-channel, heat pipe, and water cooling are reported profoundly in this review article. The data are categorized and the results of the recent studies are summarized for each method. Critical review on use of various optimization algorithms (like ant colony, genetic, particle swarm, response surface, NSGA-II, etc.) for design parameter optimization are presented and categorized for different BTMS to boost their objectives. The single objective optimization techniques helps in obtaining the optimal value of important design parameters related to the thermal performance of battery cooling systems. Finally, multi-objective optimization technique is also discussed to get an idea of how to get the trade-off between the various conflicting parameters of interest such as energy, cost, pressure drop, size, arrangement, etc. which is related to minimization and thermal efficiency/performance of the battery system related to maximization. This review will be very helpful for researchers working with an objective of improving the thermal performance and life span of the LIBs.

16.
J Environ Manage ; 282: 111917, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33453625

RESUMO

This study investigated the engine performance and emission characteristics of biodiesel blends with combined Graphene oxide nanoplatelets (GNPs) and 10% v/v dimethyl carbonate (DMC) as fuel additives as well as analysed the tribological characteristics of those blends. 10% by volume DMC was mixed with 30% palm oil biodiesel blends with diesel. Three different concentrations (40, 80 and 120 ppm) of GNPs were added to these blends via the ultrasonication process to prepare the nanofuels. Sodium dodecyl sulphate (SDS) surfactant was added to improve the stability of these blends. GNPs were characterised using Scanning Electron Microscope (SEM) and Fourier Transform Infrared (FTIR), while the viscosity of nanofuels was investigated by rheometer. UV-spectrometry was used to determine the stability of these nanoplatelets. A ratio of 1:4 GNP: SDS was found to produce maximum stability in biodiesel. Performance and emissions characteristics of these nanofuels have been investigated in a four-stroke compression ignition engine. The maximum reduction in BSFC of 5.05% and the maximum BTE of 22.80% was for B30GNP40DMC10 compared to all other tested blends. A reduction in HC (25%) and CO (4.41%) were observed for B30DMC10, while a reduction in NOx of 3.65% was observed for B30GNP40DMC10. The diesel-biodiesel fuel blends with the addition of GNP exhibited a promising reduction in the average coefficient of friction 15.05%, 8.68% and 3.61% for 120, 80 and 40 ppm concentrations compared to B30. Thus, combined GNP and DMC showed excellent potential for utilisation in diesel engine operation.


Assuntos
Biocombustíveis , Emissões de Veículos , Monóxido de Carbono/análise , Formiatos , Gasolina , Grafite
17.
Sci Rep ; 10(1): 21960, 2020 12 15.
Artigo em Inglês | MEDLINE | ID: mdl-33319818

RESUMO

The main goal of the present work was to develop a value-added product of biodegradable material for sustainable packaging. The use of agriculture waste-derived carboxymethyl cellulose (CMC) mainly is to reduce the cost involved in the development of the film, at present commercially available CMS is costly. The main focus of the research is to translate the agricultural waste-derived CMC to useful biodegradable polymer suitable for packaging material. During this process CMC was extracted from the agricultural waste mainly sugar cane bagasse and the blends were prepared using CMC (waste derived), gelatin, agar and varied concentrations of glycerol; 1.5% (sample A), 2% (sample B), and 2.5% (sample C) was added. Thus, the film derived from the sample C (gelatin + CMC + agar) with 2.0% glycerol as a plasticizer exhibited excellent properties than other samples A and B. The physiochemical properties of each developed biodegradable plastics (sample A, B, C) were characterized using Fourier Transform Infra-Red (FTIR) spectroscopy and Differential Scanning Calorimetry (DSC), Thermogravimetric analysis (TGA). The swelling test, solubility in different solvents, oil permeability coefficient, water permeability (WP), mechanical strength of the produced material was claimed to be a good material for packaging and meanwhile its biodegradability (soil burial method) indicated their environmental compatibility nature and commercial properties. The reflected work is a novel approach, and which is vital in the conversion of organic waste to value-added product development. There is also another way to utilize commercial CMC in preparation of polymeric blends for the packaging material, which can save considerable time involved in the recovery of CMC from sugarcane bagasse.

18.
Handchir Mikrochir Plast Chir ; 46(1): 31-3, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24573826

RESUMO

While diaphyseal fractures of the forearm are a common orthopedic injury, Galeazzi fractures are difficult to treat. The current knowledge on pathobiomechanics and modified therapeutic decisions implicate the need to devise an updated classification and treatment regimen of Galeazzi fractures. We challenge the concept that isolated fractures of the radius should be considered as a Galeazzi fractures as long as stability of the distal radioulnar joint is not proven. Contrary to others we demonstrate that the fracture location alone is not sufficient to determine the stability of the distal radioulnar joint.


Assuntos
Placas Ósseas , Fixação Interna de Fraturas/métodos , Luxações Articulares/classificação , Luxações Articulares/cirurgia , Fraturas do Rádio/classificação , Fraturas do Rádio/cirurgia , Traumatismos do Punho/classificação , Traumatismos do Punho/cirurgia , Parafusos Ósseos , Fios Ortopédicos , Diáfises/diagnóstico por imagem , Diáfises/lesões , Diáfises/cirurgia , Consolidação da Fratura/fisiologia , Humanos , Luxações Articulares/diagnóstico por imagem , Complicações Pós-Operatórias/diagnóstico por imagem , Radiografia , Fraturas do Rádio/diagnóstico por imagem , Amplitude de Movimento Articular/fisiologia , Fraturas da Ulna/classificação , Fraturas da Ulna/diagnóstico por imagem , Fraturas da Ulna/cirurgia , Traumatismos do Punho/diagnóstico por imagem
19.
Acta Chir Orthop Traumatol Cech ; 77(6): 457-62, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21223824

RESUMO

Over the past fifty years, treatment outcomes of traumatic injuries in the upper limb have improved with the advent of better implants. However, the Monteggia fracture is often still associated with various complications, poor functional outcomes and a relatively high rate of revision surgeries. Rigid anatomic fixation of ulnar fracture is paramount. Open relocation of the radial head and soft tissue procedures are redundant. Monteggia fractures are challenging to treat. Critical analysis with respect to the high rate of complications and unsatisfactory functional outcomes is required. The type of fracture and associated injuries such as coronoid fracture and radial head fracture appear to influence the outcome in most cases. Negative prognostic factors such as prolonged immobilization, associated coronoid and radial head fractures must be minimized and treated appropriately. Prior to surgery the patient should be informed regarding the possible risk of residual functional limitations and the potential need for further revision surgeries.


Assuntos
Fratura de Monteggia/cirurgia , Adulto , Fixação Interna de Fraturas/métodos , Humanos , Fratura de Monteggia/classificação , Fratura de Monteggia/complicações , Fratura de Monteggia/diagnóstico , Cuidados Pós-Operatórios
20.
Z Orthop Unfall ; 145(2): 199-206, 2007.
Artigo em Alemão | MEDLINE | ID: mdl-17492561

RESUMO

AIM: Prosthetic replacement in the hand must address such unique challenges as preservation of the collateral ligaments, tendon balancing,and Stability. Surface replacement arthroplasty can be an alternative to other current implants. The purpose of this study was to evaluate the metacarpophalangeal joint kinematics after surface replacement arthroplasty. METHOD: The kinematics of pyrolytic carbon as a surface replacement implant for the metacarpophalangeal joint (MCP) was compared with the intact MCP joint in eight fresh cadaver long fingers by means of an electromagnetic tracking system (Polhemus, Colchester, VT). The eight human cadaver MCP joints were tested before implantation, after implantation, after collateral ligaments resection, and after collateral ligaments reconstruction. RESULTS: The kinematics of the MCP joint is reproduced by the joint surface replacement arthroplasty when normal ligament tension was present. The maximum angular displacement of the pyrocarbon implant was 378 for lateral deviation and 338 for rotation during the passive flexion and extension motion. The instantaneus center of rotation (ICR) after implant insertion was nearly identical to the center of rotation of the normal joint. The results also indicated that the collateral ligaments provide the primary stability of the MCP joint. No significant differences in lateral and rotational stability after surface replacement arthroplasty were noted. While collateral ligaments resection significantly affected the stability of the MCP joint. CONCLUSION: The ICR of the pyrocarbon implant most closely matched that of the intact MCP joint. The pyrocarbon implant provides suitable stability to radio-ulnar deviation and rotational stresses as a resurfacing implant and it simulates the kinematics of the intact MCP joint. By using new materials and taking the anatomical and biomechanical requirements into consideration, the endoprosthesis of the finger joints has created an option to achieve good long-term results. The inadequate results of earlier and current prostheses are a consequence of their mechanical construction and their materials. The success of the new implants could be proven by preferably long-term, controlled studies.


Assuntos
Artroplastia de Substituição de Dedo/instrumentação , Artroplastia de Substituição de Dedo/métodos , Distinções e Prêmios , Instabilidade Articular/fisiopatologia , Articulação Metacarpofalângica/fisiopatologia , Articulação Metacarpofalângica/cirurgia , Fenômenos Biomecânicos/história , Cadáver , Elasticidade , Desenho de Equipamento , Análise de Falha de Equipamento , Alemanha , História do Século XXI , Humanos , Técnicas In Vitro , Instabilidade Articular/etiologia , Minnesota , Ortopedia/história , Amplitude de Movimento Articular , Estresse Mecânico , Resultado do Tratamento
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