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1.
Heliyon ; 9(6): e16390, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37274726

RESUMO

Heat transfer in water with the help of solar energy is an effective way to harness renewable energy and reduce reliance on non-renewable sources of energy. The utilization of turbulent promoters is an efficient solution to ameliorate the performance of heat exchangers (HE). The current work summarizes the experimental and numerical behaviour of HE reported in the literature, including the thermal examinations of HT and fluid flow characteristics with various turbulent promoters and tube arrangements. This article reviews multiple studies in which different twisted tape (TT) geometry enhances the HT rate in various HE tubes. The current work also compares the thermal performance (η) of TT configurations in HE tubes using correlations developed by different investigators. Maximum heat transfer and minimum friction factor concerning fluid utilized in the system may also produce the optimal form for twisted tapes.

2.
Materials (Basel) ; 15(8)2022 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-35454429

RESUMO

The realization of products from materials with high properties generally involves very high energy consumption. Thus, in the research, it was considered to optimize the machining process by cutting of an aluminum bronze alloy, so as to obtain a reduction in energy consumption in correlation with the roughness of the machined surfaces. The research focused on the processing of a semi-finished product with a diameter of Ø = 20 mm made of aluminum bronze (C62300). In addition, in the research, the aim was to establish some correlations between the amount of power consumed and the quality of the surfaces processed by cutting. In this sense, the forces were measured in the 3 directions specific to the cutting process (Fc; Ff; Fp) for 3 tools construction variants and power consumed. The results showed that, if a certain constructive variant of the cutting tool is used in the processing, a reduction of the power consumed to cutting can be obtained by approximately 30% and a reduction of the roughness of the processed surface by approximately 90-100%. Furthermore, following the statistical processing of the results, it was shown that it would be advisable to use, especially in roughing processes, the cutting tool variant that offers the greatest reduction in roughness and cutting power.

3.
Med Ultrason ; 22(2): 189-196, 2020 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-32190852

RESUMO

Pentalogy of Cantrell (POC) is a rare condition characterized by complete or partial expression of 5 types of congenital birth defects originating in (1) the lower sternum, (2) the anterior diaphragm, (3) the diaphragmatic pericardium, (4) the midline/ventral supraumbilical abdominal wall region, and (5) the heart. POC can be diagnosed antenatally by means of ultrasonography (US), the task being difficult if defects are minor. Advances in the field of US and the introduction of the first morphology trimester as state-of-the-art pregnancy monitoring, facilitate the early diagnosis of this condition. We performed a systematic review on 67 reported cases of POC diagnosed in the first trimester of pregnancy (published from January 1980 to July 2019). The aim of our systematic review was twofold: to assess the main US findings in the first trimester of pregnancy and to increase awareness of early diagnostic possibilities. Our study showed that POC can be diagnosed in the first trimesterof pregnancy based on key US findings such as the association between omphalocele and ectopia cordis. When these two anomalies are present, increased nuchal translucency can also be considered a marker of POC in the first trimester.


Assuntos
Pentalogia de Cantrell/diagnóstico por imagem , Primeiro Trimestre da Gravidez , Ultrassonografia Pré-Natal/métodos , Feminino , Humanos , Gravidez , Síndrome
4.
Med Ultrason ; 20(2): 221-227, 2018 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-29730690

RESUMO

Open spina bifida, also known as spina bifida aperta is a neural tube defect involving the lack of closure of vertebral arches and associated meninges and/or spinal cord abnormalities.Ultrasound examination is the gold standard for the diagnosis of spina bifida aperta. It represents the main imaging tool used to ascertain this diagnosis early in gestation. Three-dimensional ultrasound is necessary to detect the level and the size of the defect. Magnetic resonance imaging (MRI) represents a more sensitive tool, giving specific information of the defect and associated anomalies, playing an important role in ruling out differential diagnosis. Due to the advent of MRI use, it is possible today to achieve in utero treatment of fetuses with this pathology. The aim of the current review is to provide an update of literature regarding the role of ultrasound and MRI in the prenatal diagnosis of spina bifida aperta.


Assuntos
Imageamento por Ressonância Magnética/métodos , Diagnóstico Pré-Natal/métodos , Espinha Bífida Cística/diagnóstico por imagem , Ultrassonografia/métodos , Feminino , Humanos , Gravidez , Coluna Vertebral/diagnóstico por imagem , Ultrassonografia Pré-Natal
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