The passive bristling mechanism of the scales on the shortfin mako shark () is hypothesized to play a crucial role in controlling flow separation. In the hypothesized mechanism, the scales are triggered in response to patches of reversed flow at the onset of separation occurring in the low-speed streaks that form in a turbulent boundary layer. The two goals of this investigation were as follows: (1) to measure the reversing flow occurring within the low-speed streaks in a separating turbulent boundary layer; (2) to understand the passive flow control mechanism of movable shark skin scales that inhibit reversing flow within the low-speed streaks.
View Article and Find Full Text PDFThis smooth flat experimental study investigates the capability of mako shark scales to control flow separation when placed downstream of the onset of turbulent boundary layer separation and within the reattachment region. The objective of the study is to validate the hypothesis that the shark scales' bristling and recoiling would prevent the flow separation on the flank region (the fastest flow region) of the shark. A rotating cylinder was used to induce an adverse pressure gradient over a flat plate to produce a region of separated flow where the shark skin specimen was mounted.
View Article and Find Full Text PDFThe need to find alternative materials to replace aqueous amine solutions for the capture of CO in post-combustion technologies is pressing. This study assesses the CO sorption capacity and CO/N selectivity of three dicationic ionic liquids with distinct anions immobilized in commercial mesoporous silica support (SBA- 15). The samples were characterized by UART-FTIR, NMR, Raman, FESEM, TEM, TGA, Magnetometry (VSM), BET and BJH.
View Article and Find Full Text PDFBackground: Approximately 80% of infected women infected by Chlamydia trachomatis are asymptomatic, although this infection can lead to serious complications in the female reproductive tract. Few data on Chlamydia infection and genotypes are available in Amazonian communities.
Objectives: To describe the prevalence of and associated factors and to identify the genotypes of sexual C.
Encapsulated ionic liquids as green solvents for CO capture are reported in this work. We present a novel combination of water-based poly(ionic liquid) and imidazolium-based ionic liquids (Emim[X]). Poly(diallyldimethylammonium tetrafluoroborate)/Emim[X] capsules were developed for the first time using Nano Spray Dryer B-90.
View Article and Find Full Text PDFThe human T-lymphotropic virus type 1 (HTLV-1), isolated in 1980, causes T-cell leukemia/lymphoma in adulthood, a type of lymphoproliferative disease, and chronic HTLV-1-associated myelopathy, a disease that causes paralysis of the lower limbs, which occur in about 5% of cases in this viral infection. This study aimed to establish the hematological profile of patients with HTLV-1 infection in Belém do Pará, describing the hematological parameters under study, estimating the frequency of lymphocytic atypical, and associating the hematological profile with diseases and symptoms. Hematologic data from 202 individuals were analyzed, including 87 HTLV-1 infected individuals and 115 non-HTLV-1 infected individuals as a control group, composed, at a great part, of relatives of the infected.
View Article and Find Full Text PDFPLoS One
July 2022
Background: The Human Papillomavirus (HPV) and Chlamydia trachomatis are the most prevalent Sexually Transmitted Infections (STIs) worldwide, and are associated cervical cancer and pelvic inflammatory disease, respectively. However, 80% of women testing positive are asymptomatic. In the Amazon region, young women, in particular, are widely exposed to the infections and their consequences.
View Article and Find Full Text PDFCO separation from natural gas is considered to be a crucial strategy to mitigate global warming problems, meet product specification, pipeline specs and other application specific requirements. Silica xerogels (SX) are considered to be potential materials for CO capture due to their high specific surface area. Thus, a series of silica xerogels functionalized with imidazolium, phosphonium, ammonium and pyridinium-based room-temperature ionic liquids (RTILs) were synthesized.
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