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1.
Turk J Med Sci ; 54(1): 204-212, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38812647

RESUMO

Background/aim: Male infertility rises for many reasons, along with age; therefore, we aimed to research the characterization of aquaporin-3, 7, and 8 in human sperm belonging to different age groups. Material and methods: This study was conducted on sperm samples of men aged over 18 years. A total of 60 men were included in the study and divided into three age groups: group 1, age 18-25 years (n = 20); group 2, age 26-35 years (n = 20); and group 3, age ≥35 years (n = 20). Sperm ejaculates obtained from each participant were used for spermiogram tests, Kruger strict morphology analysis, and immunohistochemistry. Results: We observed no statistically significant differences in terms of macroscopic and microscopic sperm testing. The immunostaining score of aquaporin-3 was the lowest in group 1 and increased in group 3 and group 2, respectively (p < 0.05). Aquaporin-8 immunostaining only increased in group 2 (p < 0.05). Aquaporin-7 immunostaining scores were not different between the groups (p > 0.05). When the immunostaining scores of aquaporin molecules were compared with each other, aquaporin-7 was significantly increased compared with the others (p < 0.05). Conclusion: According to the results, it can be stated that aquaporin-3 and aquaporin-8 molecules were more expressed at age 26 to 35 years, and aquaporin-7 was densely expressed from age 18 to 25 years. If the characterization of these molecules is adversely affected, male infertility may eventually emerge. We recommend further advanced-level studies on this subject.


Assuntos
Aquaporina 3 , Aquaporinas , Espermatozoides , Humanos , Masculino , Adulto , Aquaporinas/metabolismo , Aquaporinas/análise , Espermatozoides/metabolismo , Adulto Jovem , Adolescente , Aquaporina 3/metabolismo , Aquaporina 3/análise , Infertilidade Masculina/metabolismo , Fatores Etários , Imuno-Histoquímica , Análise do Sêmen/métodos
2.
Sci Rep ; 13(1): 7714, 2023 May 12.
Artigo em Inglês | MEDLINE | ID: mdl-37173363

RESUMO

Wood fiber is a great potential supportive material for creating a new composite the phase change materials (PCM) due to its beneficial qualities, including high sorption competency, low density, enviro -friendliness, economic effectiveness, and chemical inertness. The main objective of this paper is to study the effect of using the wood fiber/eutectic mixture of stearic and capric acid on the fuel, cost, and carbon emission-saving potentials for various PCM cases. Which experiences a phase transition within the thermally pleasant temperature range of buildings, used for the building's thermal energy storing purposes and consumption cost saving. The energy performance analysis was carried out for buildings incorporated with stearic and capric acid eutectic mixture of PCM with wood fiber-based insulation material (INS) in different climate regions. The results showed that the largest energy-saving capacity belongs to PCM5. The energy saving reaches 52.7% for PCM5 for a thickness of 0.1 m. The PCM1, PCM2, PCM3, PCM4 can provide energy saving rates of 23.5%, 34.3%, 44.7% and 50.5%, respectively. INS-PCM5 can provide about 1.74-, 1.5-, and 1.33 times larger cost savings than INS in 2nd, 3rd, and 4th regions for all fuels. The payback period varies between 0.37 and 5.81 years regarding the fuel and Region. Finally, the results indicate that the proposed composite provided a promising energy-saving potential in building applications by reducing.

3.
Materials (Basel) ; 15(24)2022 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-36556713

RESUMO

Significant research investigations on the characteristics of unexplored clay deposits are being conducted in light of the growing need for clay in the ceramic industry and the variable chemistry of clays. Parallel to this, the generation of waste materials like fly ash, ferrochrome slag, and silica fume is also increasing, responsible for environmental degradation. This paper aims to study the mineralogical properties of pure clays (one specimen from Siberia and five specimens from different locations in Turkey), and the effect of mentioned waste materials on the index properties of clays obtained. This study is divided into two phases, wherein in the first phase, the pure clay specimens are analyzed against mineralogical properties (i.e., chemical composition, thermal analysis, and particle size distribution). While in the second phase, index properties of pure clay specimens and clay specimens modified with 0-50% fly ash, ferrochrome slag, and silica fume are analyzed. The results reveal that the clay specimens from Turkey (USCS classification: CL) are fit for the ceramic industry and bricks production, and incorporation of waste materials can further improve their index properties. It is also observed that incorporation of 10-30% fly ash and ferrochrome slag have higher efficiency in reducing the plasticity index of clays studied as compared to the addition of silica fume.

4.
Environ Sci Pollut Res Int ; 29(59): 88710-88724, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35838937

RESUMO

Due to the increased population in the urbanized areas, considerable attention is being paid on the development of energy-efficient buildings. In construction, the use of insulating foams has grabbed considerable attention in recent decades due to their porous structure that can reduce thermo-acoustic conductivity leading to higher energy efficiency. Nonetheless, the production of certain foams (e.g., polymer foams) is based on harmful chemical substances, such as isocyanate, as well as having difficulty being recycled. In this regard, this study adopted the use of hydrodesulfurization (HDS) spent catalyst, which is a byproduct of petroleum industry and is known to be a hazardous solid waste material, to produce a more environmentally friendly composite foam with lower thermal conductivity. In this sense, a series of material property tests, as well as thermal conductivity test, have been conducted. In addition, to further confirm the impact of HDS inclusion in the produced foams, energy cost savings and CO2 emission reduction based on their actual application in four different environments and four different fuel types for heating have been evaluated. The results are found to be highly promising and point to the great potential of utilizing HDS spent catalyst as a hazardous waste to enhance the efficiency of foams leading to CO2 emission and energy use reduction by up to 68.79 kg/m2 and 8.6 kWh/m2, respectively. Finally, this would reduce the heating cost, up to 0.69 $/m2 in an idealized building. In the end, suggestions for future studies in this area are also provided.

6.
Environ Sci Pollut Res Int ; 29(47): 71936-71947, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35608771

RESUMO

Within the scope of the present study, the marble cutting waste, which is an industrial waste of different sizes (< 75 µm and < 150 µm), was incorporated into the clay structure at various rates and a total of 36 series bricks were produced. The brick mixtures were prepared by the semi-dry molding method and the brick specimens were sintered for three temperatures (850 °C, 950 °C, and 1050 °C). The fired bricks containing marble cutting waste with a lower particle size (75 µm) have higher compressive strength. However, all samples produced can meet the relevant standard requirements in terms of compressive strength. Thermal conductivity decreased from 1.008 to 0.775 W/mK with the incorporation of marble cutting waste, a decrease of approximately 23.11%. The effects of grain size, firing temperature, and marble cutting waste concentration on the quadratic model were statistically determined by variance analysis (ANOVA). According to statistical findings, the order of importance of design factors for brick properties (except for compressive strength) is marble cutting waste > firing temperature > particle size. For compressive strength, the most dominant factor is amount of marble cutting waste, followed by particle size and firing temperature, respectively. Consequently, the results suggest that marble cutting waste does not need to be reduced to smaller particle sizes to improve the fired clay brick properties.

7.
Materials (Basel) ; 15(2)2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-35057360

RESUMO

Fly ash wastes (silica, aluminum and iron-rich materials) could be smartly valorized by their incorporation in concrete formulation, partly replacing the cement. The necessary binding properties can be accomplished by a simple procedure: an alkali activation process, involving partial hydrolysis, followed by gel formation and polycondensation. The correlations between the experimental fly ash processing conditions, particle characteristics (size and morphology) and the compressive strength values of the concrete prepared using this material were investigated by performing a parametric optimization study to deduce the optimal processing set of conditions. The alkali activation procedure included the variation of the NaOH solutions concentration (8-12 M), temperature values (25-65 °C) and the liquid/solid ratio (1-3). The activation led to important modifications of the crystallography of the samples (shown by powder XRD analysis), their morphologies (seen by SEM), particle size distribution and Blaine surface values. The values of the compressive strength of concrete prepared using fly ash derivatives were between 16.8-22.6 MPa. Thus, the processed fly ash qualifies as a proper potential building material, solving disposal-associated problems, as well as saving significant amounts of cement consumed in concrete formulation.

8.
J Environ Manage ; 268: 110732, 2020 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-32510452

RESUMO

Evaluation of energy performance of a proposed lightweight concrete, a structural component, in a building application is a novel approach and significant attempt for the future of energy-efficient buildings. Buildings are one of the largest energy consumers in the world. Thermal protection in a building is the most effective way for energy saving. Many stimulatory measures for the spreading of energy savings technologies have been recently applied into the building sectors. In this study, an investigation was carried out based upon an experimental investigation to decide the thermal properties of the lightweight concrete with different ratios of vermiculite. Moreover, analytical simulation to evaluate the energy consumption in a real building application was carried out for various fuels and different climate regions of Turkey. The results show that the most significant reduction in the total heat need occurs in the 4th region, with about 5.6 kWh/m2-year for a thickness of 0.2 m. An energy-saving of 7.5% can be achieved in the 1st region. The proposed concrete can provide a significant reduction in energy consumption and can reduce the carbon emission related to the lower energy need of the buildings. The annual saving can increase to 0.61 $/m2 for LPG in the 4th region. The payback period varies between 1.4 years and 9 years, depending on the fuel. Many OECD countries having a high population pay higher prices for electricity and natural gas compared to Turkey. It means that such an energy-efficient material can save more price due to their higher fuel cost.


Assuntos
Clima , Eletricidade , Condutividade Térmica , Turquia
9.
Materials (Basel) ; 13(7)2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32244790

RESUMO

Hindered amine light stabilizers (HALSs) and nano ZnO were used to stabilize polypropylene (PP) film-based formulations that were exposed to ultraviolet (UV) light for different lengths of time, simulating the harsh outdoor weather of Dallas, Texas, USA. UV doses applied in our laboratory are 121 times larger than the UV dose provided by the sunlight in Texas. 15 different compositions were studied. Tensile behavior, UV transmittance, thermal stability (by thermogravimetric analysis) and dynamic friction of the so exposed PP-based films were determined. Scanning electron micrographs of fracture surfaces were obtained. Nano-ZnO-containing stabilizers impart strong UV resistance to our films. The combination of HALSs and nano-ZnO stabilizers makes the PP films harder-which is important for some PP applications, such as toy manufacturing.

10.
J Environ Manage ; 181: 185-192, 2016 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-27343435

RESUMO

Production of porous clay bricks lightened by adding olive mill waste as a pore making additive was investigated. Factors influencing the brick manufacturing process were analyzed by an experimental design, Taguchi method, to find out the most favorable conditions for the production of bricks. The optimum process conditions for brick preparation were investigated by studying the effects of mixture ratios (0, 5 and 10 wt%) and firing temperatures (850, 950 and 1050 °C) on the physical, thermal and mechanical properties of the bricks. Apparent density, bulk density, apparent porosity, water absorption, compressive strength, thermal conductivity, microstructure and crystalline phase formations of the fired brick samples were measured. It was found that the use of 10% waste addition reduced the bulk density of the samples up to 1.45 g/cm(3). As the porosities increased from 30.8 to 47.0%, the compressive strengths decreased from 36.9 to 10.26 MPa at firing temperature of 950 °C. The thermal conductivities of samples fired at the same temperature showed a decrease of 31% from 0.638 to 0.436 W/mK, which is hopeful for heat insulation in the buildings. Increasing of the firing temperature also affected their mechanical and physical properties. This study showed that the olive mill waste could be used as a pore maker in brick production.


Assuntos
Materiais de Construção , Olea/química , Gerenciamento de Resíduos/métodos , Resíduos , Silicatos de Alumínio/química , Argila , Força Compressiva , Indústria de Processamento de Alimentos , Resíduos Industriais , Porosidade , Temperatura , Condutividade Térmica
11.
Appl Radiat Isot ; 70(1): 341-5, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21996671

RESUMO

(241)Am-Be source and three samples including different amounts of boron atoms per unit volume called colemanite, ulexite and tincal were used in total macroscopic cross section experiments. Also FLUKA Monte Carlo code was used to simulate total macroscopic cross sections, absorbed doses and deposited energies by low energy neutron interactions. Besides half value layers of samples were calculated and compared to paraffin. As a result, ascending concentration of boron atoms can enhance neutron shielding property of samples.


Assuntos
Amerício/análise , Amerício/química , Compostos de Boro/química , Modelos Químicos , Nêutrons , Proteção Radiológica/métodos , Simulação por Computador , Teste de Materiais
12.
J Hazard Mater ; 192(1): 108-15, 2011 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21616593

RESUMO

Two problems are addressed simultaneously. One is the utilisation of sludge from the treatment of wastewater. The other is the modification of the mechanical properties of concrete. The sludge was subjected to two series of treatments. In one series, coagulants were used, including ferrous sulphate, aluminium sulphate or aluminium polyhydroxychloride. In the other series, an electrochemical treatment was applied with several starting values of pH. Then, concretes consisting of a cement matrix, silica sand, marble and one of the sludges were developed. Specimens without sludge were prepared for comparison. Curing times and aggregate concentrations were varied. The compressive strength, compressive strain at yield point, and static and dynamic elastic moduli were determined. Diagrams of the compressive strength and compressive strain at the yield point as a function of time passed through the minima as a function of time for concretes containing sludge; therefore, the presence of sludge has beneficial effects on the long term properties. Some morphological changes caused by the presence of sludge are seen in scanning electron microscopy. A way of utilising sludge is thus provided together with a way to improve the compressive strain at yield point of concrete.


Assuntos
Materiais de Construção , Teste de Materiais , Esgotos , Poluentes da Água , Eletroquímica
13.
Biol Trace Elem Res ; 135(1-3): 253-63, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19763408

RESUMO

The levels of liver lipid peroxidation, glutathione peroxidase, reduced glutathione, and vitamins A and E were used to follow the level of oxidative damage caused by ionizing radiation in pregnant rats. The possible protective effects of selenium and vitamin E supplemented to rats housed in concrete-protected cages using hematite and colemanite were tested and compared to untreated controls. Ninety-six rats were randomly divided into four main equal groups namely control (A), normal concrete (B), concrete containing colemanite (C), and concrete containing hematite (D). Except group A, all groups exposed to 7 Gy radiation. The four main groups were divided into four subgroups each as follows: subgroups 1 (n = 6): nonpregnant control rats. Subgroups 2 (n = 6): selenium and vitamin E combination was intraperitoneally (i.p.) given to the nonpregnant rats for 20 days. Subgroups 3 (n = 6): pregnant control rats. Subgroups 4 (n = 6): selenium and vitamin E combination was i.p. given to the pregnant rats for concessive 20 days. Lactate dehydrogenate, alkaline phosphates, and lipid peroxidation values were higher in subgroups 1 and 3 than in no radiation group although glutathione peroxidase and vitamin E levels in liver were lower in radiation group than in no radiation group. Lactate dehydrogenate activity and lipid peroxidation levels were found to be decreased in subgroups 2 and 4 protected with concrete containing hematite and colemanite when compared to subgroup 1 and 3 with normal concrete. The radiation doses in rats housed by concrete without colemanite and hematite exposed radiation clearly showed liver degeneration. In conclusion, selenium and vitamin E supplementations and housing by concrete with colemanite was found to offer protection against gamma-irradiation-induced liver damage and oxidative stress in rats, probably by exerting a protective effect against liver necrosis via its free radical scavenging and membrane stabilizing. Protective effects of colemanite in the liver seem to be more important than in hematite.


Assuntos
Boratos/uso terapêutico , Compostos Férricos/uso terapêutico , Fígado/efeitos da radiação , Gravidez/efeitos da radiação , Vitamina E/uso terapêutico , Animais , Feminino , Glutationa Peroxidase/metabolismo , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos da radiação , Fígado/efeitos dos fármacos , Minerais , Lesões Experimentais por Radiação/tratamento farmacológico , Radiação Ionizante , Protetores contra Radiação/uso terapêutico , Ratos , Ratos Wistar , Selênio/uso terapêutico
14.
Biol Trace Elem Res ; 132(1-3): 153-63, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19396408

RESUMO

The levels of blood lipid peroxidation, glutathione peroxidase, reduced glutathione, and vitamin C were used to follow the level of oxidative damage caused by 2.45 GHz electromagnetic radiation in rats. The possible protective effects of selenium and L-carnitine were also tested and compared to untreated controls. Thirty male Wistar Albino rats were equally divided into five groups, namely Groups A1 and A2: controls and sham controls, respectively; Group B: EMR; Group C: EMR + selenium, Group D: EMR + L-carnitine. Groups B­D were exposed to 2.45 GHz electromagnetic radiation during 60 min/ day for 28 days. The lipid peroxidation levels in plasma and erythrocytes were significantly higher in group B than in groups A1 and A2 (p<0.05), although the reduced glutathione and glutathione peroxidase values were slightly lower in erythrocytes of group B compared to groups A1 and A2. The plasma lipid peroxidation level in group A2 was significantly lower than in group B (p<0.05). Erythrocyte reduced glutathione levels (p<0.01) in group B; erythrocyte glutathione peroxidase activity in group A2 (p<0.05), group B (p<0.001), and group C (p<0.05) were found to be lower than in group D. In conclusion, 2.45 GHz electromagnetic radiation caused oxidative stress in blood of rat. L-carnitine seems to have protective effects on the 2.45-GHz-induced blood toxicity by inhibiting free radical supporting antioxidant redox system although selenium has no effect on the investigated values.


Assuntos
Carnitina/farmacologia , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/efeitos da radiação , Selênio/farmacologia , Animais , Antioxidantes/metabolismo , Ácido Ascórbico/sangue , Glutationa/sangue , Glutationa Peroxidase/sangue , Peroxidação de Lipídeos/efeitos dos fármacos , Peroxidação de Lipídeos/efeitos da radiação , Masculino , Ratos , Ratos Wistar
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