Influence of hydrodynamic parameters in plate heat exchangers in ice slurry transport

Jiménez Pacheco Hugo Guillermo,Milon Guzmán Juan José,Miranda Ramos Lilia Mary,Delgado Sarmiento Pavel Kewin,Linares Flores Castro Antonio Erick,Leal Braga Sergio 대한설비공학회 2023 International Journal of Air-Conditioning and Refr Vol.31 No.1

Ice slurry is applied in different refrigeration and air conditioning systems, and among its main advantages is the ability to store latent heat and be pumpable as cold water. This fluid can be used for thermal storage instead of cold water or solid ice, since, at certain concentrations, it can be pumped through heat exchangers. For this technology to be widely used, the equipment must be designed considering the heat exchange characteristics. This study developed an experimental system to study the parameters that influence heat exchange, using ice slurry in a plate heat exchanger and water as a thermal load. Several situations with different flows and initial fractions of ice in ice slurry were analyzed. The input conditions of the thermal load were kept constant, the temperature, the pressure drop and the flow of the ice slurry in the heat exchanger were controlled, according to the Nusselt, Prandtl, and Reynolds coefficients. Results show that the global heat exchange coefficient increases with the increase of the initial ice fraction; the cooling capacity of the heat exchanger increases when ice slurry is used as a fluid. For flow rates greater than 0.16 kg/s and ice fractions above 11%, ice crystals are generated at the heat exchanger outlet, due to the ice slurry’s higher viscosity, at approximately 0.003 Pa at the outlet, since the pressure drop increases as the initial ice fraction increases. Results show ice slurry thermohydraulic behavior. Its use shows favorable characteristics in heat exchange. Ice slurry is applied in different refrigeration and air conditioning systems, and among its main advantages is the ability to store latent heat and be pumpable as cold water. This fluid can be used for thermal storage instead of cold water or solid ice, since, at certain concentrations, it can be pumped through heat exchangers. For this technology to be widely used, the equipment must be designed considering the heat exchange characteristics. This study developed an experimental system to study the parameters that influence heat exchange, using ice slurry in a plate heat exchanger and water as a thermal load. Several situations with different flows and initial fractions of ice in ice slurry were analyzed. The input conditions of the thermal load were kept constant, the temperature, the pressure drop and the flow of the ice slurry in the heat exchanger were controlled, according to the Nusselt , Prandtl , and Reynolds coefficients. Results show that the global heat exchange coefficient increases with the increase of the initial ice fraction; the cooling capacity of the heat exchanger increases when ice slurry is used as a fluid. For flow rates greater than 0.16 kg/s and ice fractions above 11%, ice crystals are generated at the heat exchanger outlet, due to the ice slurry’s higher viscosity, at approximately 0.003 Pa at the outlet, since the pressure drop increases as the initial ice fraction increases. Results show ice slurry thermohydraulic behavior. Its use shows favorable characteristics in heat exchange.

Effect of Spirulina maxima on Postprandial Lipemia in Young Runners: A Preliminary Report

Patricia Victoria Torres-Durán,Aldo Ferreira-Hermosillo,Arnulfo Ramos-Jiménez,Rosa Patricia Hernández-Torres,Marco Antonio Juárez-Oropeza 한국식품영양과학회 2012 Journal of medicinal food Vol.15 No.8

Trained people exhibit low plasma concentrations of triacylglcyerols in both fasting and postprandial states. Exercise practice is commonly believed to improve postprandial lipemia. In addition, elevated postprandial lipemia is an indicator of poor lipid clearance, and it has been associated with atherosclerosis, insulin resistance, and obesity. Spirulina maxima is an edible microorganism with a high nutritional value. When it is consumed, beneficial properties to health have been demonstrated, such as hypolipemic and antihypertensive properties in human beings. This work evaluates the effects of orally administrated S. maxima on postprandial lipemia in a young Mexican sporting population after 15 days of consumption,as a possible alternative treatment to improve their lipid clearance. Forty-one runners (10–26 years old; 21 men and 20women) volunteered to participate in the study. All of them were physically active for at least 1 year before the study and were not undergoing training during the study. The subjects consumed 5 g of Spirulina during 15 days. Before and after the treatment with Spirulina, they consumed (12 h fasting) a standardized meal with high fat content (53.2% total calories). Postprandial lipemia was measured at 1.5, 3, and 4.5 h after the fatty meal. Fasting plasma triacylglycerol (TAG) concentrations were lower after Spirulina treatment than before treatment. In addition, the postprandial area under the curve of TAG concentrations was lower after the treatment with Spirulina. Sixty-two percent of the youngest runners (10–16 years) studied exhibited the best response to the treatment. Orally administered S. maxima decreased postprandial lipemia in sporting teenagers. The youngest people were the most responsive to the beneficial effects of Spirulina on postprandial lipemia.

Growth performance, carcass traits, muscle fiber characteristics and skeletal muscle mRNA abundance in hair lambs supplemented with ferulic acid

( Edgar Fernando Peña-torres ),( Candelario Castillo-salas ),( Ismael Jiménez-estrada ),( Adriana Muhlia-almazán ),( Etna Aida Peña-ramos ),( Araceli Pinelli-saavedra ),( Leonel Avendaño-reyes ),( Cin 한국축산학회 2022 한국축산학회지 Vol.64 No.1

Ferulic acid (FA) is a phytochemical with various bioactive properties. It has recently been proposed that due to its phytogenic action it can be used as an alternative growth promoter additive to synthetic compounds. The objective of the present study was to evaluate the growth performance, carcass traits, fiber characterization and skeletal muscle gene expression on hair-lambs supplemented with two doses of FA. Thirty-two male lambs (n = 8 per treatment) were individually housed during a 32 d feeding trial to evaluate the effect of FA (300 and 600 mg d^-1) or zilpaterol hydrochloride (ZH; 6 mg d^-1) on growth performance, and then slaughtered to evaluate the effects on carcass traits, and muscle fibers morphometry from Longissimus thoracis (LT) and mRNA abundance of β2-adrenergic receptor (β₂-AR), MHC-I, MHC-IIX and IGF-I genes. FA increased final weight and average daily gain with respect to non-supplemented animals (p < 0.05). The ZH supplementation increased LT muscle area, with respect to FA doses and control (p < 0.05). Cross-sectional area (CSA) of oxidative fibers was larger with FA doses and ZH (p < 0.05). Feeding ZH increased mRNA abundance for β₂-AR compared to FA and control (p < 0.05), and expression of MHC-I was affected by FA doses and ZH (p < 0.05). Overall, FA supplementation of male hair lambs enhanced productive variables due to skeletal muscle hypertrophy caused by MHC-I up-regulation. Results suggest that FA has the potential like a growth promoter in lambs.

Abnormal expression of H-Ras induces S-phase arrest and mitotic catastrophe in human T-lymphocyte leukemia

Jorge Antonio Zamora Dominguez,Irma Olarte Carrillo,Rubén Ruiz Ramos,Christian Omar Ramos-Peñafiel,Luis Jiménez Zamudio,Ethel García Latorre,Federico Centeno Cruz,Adolfo Martínez Tovar 대한혈액학회 2023 Blood Research Vol.58 No.1

Background Leukemia is a neoplasm with high incidence and mortality rates. Mitotic death has been observed in tumor cells treated with chemotherapeutic agents. Ras family proteins participate in the transduction of signals involved in different processes, such as proliferation, differentiation, survival, and paradoxically, initiation of cell death. Methods This study investigated the effect of H-Ras expression on human T-cell acute lymphoblastic leukemia MOLT-4 cells. Cells were electroporated with either wild-type (Raswt) or oncogenic mutant in codon 12 exon 1 (Rasmut) versions of H-Ras gene and stained for morphological analysis. Cell viability was assessed using trypan blue staining and cell cycle analysis using flow cytometry. H-Ras gene expression was determined using quantitative real-time reverse transcription polymerase chain reaction. The t, ANOVA, and Scheffe tests were used for statistical analysis. Results Human T-cell acute lymphoblastic leukemia MOLT-4 cells showed nuclear fragmentation and presence of multiple nuclei and micronuclei after transfection with either wt or mutant H-Ras genes. Cell cycle analysis revealed a statistically significant increase in cells in the S phase when transfected with either wt (83.67%, P <0.0005) or mutated (81.79%, P <0.0001) H-Ras genes. Although similar effects for both versions of H-Ras were found, cells transfected with the mutated version died at 120 h of mitotic catastrophe. Conclusion Transfection of human T-cell acute lymphoblastic leukemia MOLT-4 cells with either normal or mutated H-Ras genes induced alterations in morphology, arrest in the S phase, and death by mitotic catastrophe.