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1.
J Environ Manage ; 279: 111793, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-33360275

RESUMO

This paper provides a unique review of hydrogen production methods with wastewater treatment to depict a clean and sustainable approach. Various methods for hydrogen production from wastewaters are identified and discussed with recent details by discussing the critical challenges, opportunities, and future directions. Five main performance sectors are considered in detail for each hydrogen production method of the recent case studies, including economic, environmental, social, technical, and reliability. Eight hydrogen production methods are reviewed, including anaerobic method, photo fermentation, dark fermentation, electrolysis, electrodialysis, photocatalysis, photoelectrochemical methods, and super water gasification. A comparative assessment of six reviewed methods for hydrogen production, including environmental, economic, energetic, and exergetic impacts, is evaluated. The comparative assessment results indicate that dark fermentation technology is the most economical method, and it is followed by microbial electrolysis and photofermentation. The most environmentally friendly method for the lowest global warming potential (GWP) is the microbial electrolysis method, and it is followed by photocatalysis and photoelectrochemical methods. Furthermore, the highest energy and exergy efficiencies have been recorded for the microbial electrolysis to be 68% and 64.7%, respectively.


Assuntos
Hidrogênio , Águas Residuárias , Eletrólise , Fermentação , Reprodutibilidade dos Testes
2.
Chemosphere ; 337: 139367, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37414294

RESUMO

Hydrogen is recognized as a critical substance for diversifying the global energy supply, providing new economic opportunities and realizing a carbon-free energy sector. In the current study, a life cycle assessment is conducted on a photoelectrochemical hydrogen production process of a newly developed photoelectrochemical reactor. With a photoactive electrode area of 870 cm2, the hydrogen production rate of the reactor is 47.1 µg/s while operating with the energy and exergy efficiencies of 6.3% and 6.31%, respectively. For a Faradaic efficiency of 96%, the produced current density is evaluated as 3.15 mA/cm2. A comprehensive study is conducted for a cradle-to-gate life cycle assessment of the proposed hydrogen photoelectrochemical production system. The life cycle assessment results of the proposed photoelectrochemical system are further evaluated within a comparative analysis by considering a total of four key hydrogen generation processes, namely steam-methane reforming, photovoltaics-based and wind electricity-driven proton exchange membrane water electrolysis and the current photoelectrochemical system and studying five environmental impact categories. The global warming potential of hydrogen production via the proposed photoelectrochemical cell is evaluated as 1.052 kg CO2 equivalent per kg of produced hydrogen. In the normalized comparative life cycle assessment results, the PEC-based hydrogen production is found to be the most nature-friendly option among the considered pathways.


Assuntos
Vapor , Água , Água/química , Meio Ambiente , Eletrólise/métodos , Hidrogênio/química
3.
Leg Med (Tokyo) ; 62: 102220, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36842227

RESUMO

Sex estimation is the primary step in biological profiling via identification using skeletal elements. The aim of the present study was to evaluate the usefulness of the seventh cervical vertebra for sex estimation. The cervical computed tomography scans of 200 female and 200 male patients aged ≥ 20 years were analyzed. Eight different measurements of the seventh cervical vertebra were performed, including the transverse and anteroposterior diameters of the foramen vertebra, transverse and anteroposterior diameters of the corpus vertebra inferior surface, height of the corpus vertebra, corpus vertebrae-spinous process angle, and height and length of the spinous process. Independent two-sample t-test was performed; significant differences were observed between the sexes in all measurements except corpus vertebrae-spinous process angle. Further, univariate logistic regression analyses revealed that the length of spinous process showed the highest dimorphism. Among the univariate models created, the model obtained using only the length of the spinous process reached an accuracy rate of 80 %. Multivariate logistic regression analysis (via Forward LR Wald) was used for sex estimation with an accuracy of up to 90.8 % (89 % for men and 92.5 % for women). In conclusion, the seventh cervical vertebra is dimorphic in the Turkish population and allows sex estimation with high accuracy rates.


Assuntos
Vértebras Cervicais , Tomografia Computadorizada por Raios X , Humanos , Masculino , Feminino , Caracteres Sexuais
4.
Membranes (Basel) ; 13(5)2023 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-37233583

RESUMO

The polymer electrolyte membrane and its contact with electrodes has a significant effect on the performance of fuel and electrolysis cells but the choice of commercially available membranes is limited. In this study, membranes for direct methanol fuel cells (DMFCs) were made by ultrasonic spray deposition from commercial Nafion solution; the effect of the drying temperature and presence of high boiling solvents on the membrane properties was then analyzed. When choosing suitable conditions, membranes with similar conductivity, water uptake, and higher crystallinity than comparable commercial membranes can be obtained. These show similar or superior performance in DMFC operation compared to commercial Nafion 115. Furthermore, they exhibit low permeability for hydrogen, which makes them attractive for electrolysis or hydrogen fuel cells. The findings from our work will allow for the adjustment of membrane properties to the specific requirements of fuel cells or water electrolysis, as well as the inclusion of additional functional components for composite membranes.

5.
Arch Iran Med ; 25(9): 624-633, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-37543888

RESUMO

BACKGROUND: This study aimed to evaluate the characteristics of incidental findings (IFs) on computed tomography (CT) scans of trauma admissions, examine associations between IFs and gender and age-groups, and discuss the management strategies. METHODS: The CT reports were retrospectively reviewed to evaluate IFs. Cases were divided into five age-groups (0-19, 20- 39, 40-59, 60-79,≥80). IFs were classified as "Group 1": congenital anomalies that do not require further investigation, non-degenerative/minor degenerative findings; "Group 2": findings that do not require immediate intervention, require outpatient follow-up/in case of symptoms; and "Group 3": findings that require immediate intervention/further investigation. RESULTS: There were 2385 CT scans and 1802 incidental findings (IFs) in 783 trauma cases. CT scans with IFs constituted 50.2%. The percentage of IFs was 75.6% in males and 24.4% in females, and they occurred in 4.8%, 27.6%, 44.3%, 20.9%, and 2.4% of age groups 1 to 5, respectively. Group 1 had 34.6%, group 2 had 54.6%, and group 3 had 10.8% IFs. There was not any significant association between the classification and gender or age-groups. In terms of organs, IFs of the thyroid and gall bladder & bile ducts were significantly higher among females (P=0.044 and P<0.001, respectively), while IFs in the head & neck region were significantly higher in males (P<0.001). Incidental findings in the kidney, liver, adrenal gland, and vascular structures differed significantly across age-groups (P<0.05). CONCLUSION: There were no significant relationships between the classification of IFs and gender or age-groups. However, the distribution of IFs was significantly associated with gender and age-groups in terms of organs. Healthcare professionals should consider this relationship when following up and treating patients.


Assuntos
Achados Incidentais , Tomografia Computadorizada por Raios X , Masculino , Feminino , Humanos , Estudos Retrospectivos , Pescoço
6.
Int J Neural Syst ; 30(9): 2050046, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32902344

RESUMO

Obsessive-compulsive disorder (OCD) is one of the neuropsychiatric disorders qualified by intrusive and iterative annoying thoughts and mental attitudes that are activated by these thoughts. In recent studies, advanced signal processing techniques have been favored to diagnose OCD. This research suggests four different measurements; intrinsic phase-locked value, intrinsic coherence, intrinsic synchronization likelihood, and intrinsic visibility graph similarity that quantifies the synchronization level and complexity in electroencephalography (EEG) signals. This intrinsic synchronization is achieved by utilizing Multivariate Empirical Mode Decomposition (MEMD), a data-driven method that resolves nonlinear and nonstationary data into their intrinsic mode functions. Our intrinsic technique in this study demonstrates that MEMD-based synchronization analysis gives us much more detailed knowledge rather than utilizing the synchronization method alone. Furthermore, the nonlinear synchronization method presents more consistent results considering OCD heterogeneity. Statistical evaluation using sample [Formula: see text]-test and [Formula: see text]-test has shown the significance of such new methodology.


Assuntos
Encéfalo/fisiopatologia , Sincronização de Fases em Eletroencefalografia , Modelos Teóricos , Transtorno Obsessivo-Compulsivo/fisiopatologia , Processamento de Sinais Assistido por Computador , Humanos
7.
Forensic Sci Int ; 141(1): 33-7, 2004 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-15066711

RESUMO

Soils vary among different areas, and have some characteristics because of the natural effects and transfers made by human and other living beings in time. So that forensic examination of soil is not only concerned with the analysis of naturally occurring rocks, minerals, vegetation, and animal matter. It also includes the detection of such manufactured materials such as ions from synthetic fertilizers and from different environments (e.g., nitrate, phosphate, and sulfate) as environmental artifacts (e.g., lead or objects as glass, paint chips, asphalt, brick fragments, and cinders) whose presence may impart soil with characteristics that will make it unique to a particular location. Many screening and analytical methods have been applied for determining the characteristics which differentiate and discriminate the forensic soil samples but none of them easily standardized. Some of the methods that applied in forensic laboratories in forensic soil discrimination are the color comparison of the normal air-dried (dehumidified) and overheated soil samples, macroscopic observation, and low-power stereo-microscopic observation, determination of anionic composition by capillary electrophoresis (CE), and the elemental composition by scanning electron microscope (SEM)-energy dispersive X-ray spectrometer (EDS) and other high sensitivity techniques. The objective of this study was to show the effect of the application of 9 tonnes/cm2 pressure on the elemental compositions obtained by SEM-EDS technique and comparing the discrimination power of the pressed-homogenized and not homogenized forensic soil samples. For this purpose soil samples from 17 different locations of Istanbul were collected. Aliquots of the well mixed samples were dried in an oven at 110-120 degrees C and sieved by using 0.5 mm sieve and then the undersieve fraction(<0.5 mm) of these samples put on an adhesive tape placed on a stub. About 100-150 mg aliquots of dried, sieved samples were pressed under 9 tonnes/cm2 pressure by KBr disk preparation apparatus of an infrared spectrophotometer. Surfaces of the randomized particles and the pressed disks of the soil samples were scanned and the elemental compositions were determined with scanning electron microscope JEO-JSM-5600 equipped with an energy dispersive X-ray spectrometer OXFORD Link-ISIS-300. The samples from top of the sieves were examined with stereo-microscope equipped with JVC-TK-128DE color video camera and JVC-GV-PT2, digital video printer. Natural and artificial materials that have characteristic features were identified. Then for additional confirmation all soil samples were dried at 120 degrees C and over 780 degrees C and their colors compared. We concluded that pressing the whole sieved soil samples under 9 tonnes/cm2 pressure results in smashing over the harder particles into the softer matrix and results in homogenization of the soil sample. The elemental compositions of these samples obtained by SEM-EDS with 10-fold less standard deviation (S.D.) values and so that with more reproducibility and discrimination power.


Assuntos
Medicina Legal/métodos , Microscopia Eletrônica de Varredura , Solo/análise , Espectrometria por Raios X , Pressão , Turquia
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