Effect of calcium promoter on nano structure iron catalyst for Fischer–Tropsch synthesis

The Fischer-Tropsch synthesis (FTS) has been recognized as a heterogeneous surface-catalyzed polymerization process. During this process, CHx monomers formed via the hydrogenation of adsorbed CO on transition metals produce hydrocarbons and oxygenates with a broad range of chain lengths and functional groups. A series of Fe/Cu Fischer-Tropsch synthesis catalysts incorporated with a calcium promoter were prepared by a microemulsion method. The composition of the final nanosized iron catalysts in terms of the atomic ratio is as follows: 100Fe/4Cu, 100Fe/4Cu/2Ca, 100Fe/4Cu/4Ca. XRD, BET, TEM, and TPR techniques were used to study the catalysts phase, structure, and morphology. Fischer-Tropsch synthesis (FTS) reaction test was performed in a fixed bed reactor. All the promoted catalysts, compared to the unpromoted catalysts, have higher rates of FT and the secondary reaction for CO2 production. The formation of methane and light hydrocarbons is restrained with increasing the amount of calcium. The 100Fe/4Cu/2Ca shows the best performance between the prepared catalysts.</span

Feasibility study on the use of MIL-53(Al) as a support for iron catalysts in the CO hydrogenation reaction

The study examined the potential use of MIL-53(Al), a metal-organic compound created through solvothermal synthesis, as a support for iron catalysts in Fischer-Tropsch Synthesis (FTS). Fischer-Tropsch synthesis is a crucial aspect of Gas-to-Liquid (GTL) technology used in the petrochemical industry to produce light olefins. The catalyst's activity was assessed under specific conditions, including a gas hourly space velocity (GHSV) of 2700 h-1, a hydrogen to carbon monoxide (H2/CO) feed ratio of 2:1, temperatures ranging from 310 to 330 ℃, and pressures ranging from 5 to 9 bar. The feasibility study indicated that MIL-53(Al) has the potential to be a suitable support for iron catalysts in FTS, resulting in the production of light olefins (24%) at high temperatures and low pressure

Global depression in Breast Cancer patients: systematic review and meta-analysis

Background: Breast cancer is known as one of the most common diseases among women, the psychological consequences of which are common in women and affect various aspects of their lives, so this study aims to investigate the prevalence of depression among women with breast cancer globally. Method: The present meta-analysis was performed by searching for keywords related to breast cancer and depression in 4 main databases: PubMed, Embase, Web of Sciences and Scopus in the period of January 2000 to November 2021 and the results of the study using R and CMA software were analyzed. Results: A total of 71 studies were selected in English and the results of the analysis showed that the prevalence of depression in women with breast cancer is 30.2%, with Pakistan having the highest (83%) prevalence of depression and Taiwan having the lowest (8.3%). And in the WHO regions, EMRO region had the highest (49.7%) rate and SEARO region had the lowest (23%) prevalence of depression. Also, with increasing age, the prevalence of depression among women with breast cancer increases. Conclusion: Community and family support for women with breast cancer, holding psychology and psychotherapy courses, lifestyle modifications and training in this area can be effective in preventing the reduction of the prevalence of depression, and given the pivotal role of women in family affairs, this This can be in line with the work of health system policymakers

Introducing Model for Determining the Center of Mass in Children aged 6 to 12 years old in Isfahan

Objective: The center of mass is dependent on the distribution of mass and length of the upper parts of the body to the lower parts of the body. This plays a fundamental role in the body's balance, which can be measured in various ways. The purpose of this study was to provide a model for determining the center of mass of girls and boys aged 6 to 12 years. Methods: Participants in this study were 192 healthy girls and 192 healthy boys who were studying in Isfahan, from which 154850 students were selected through cluster sampling. For this purpose, their mass was measured with a bascule, variables related to stature with meter and center of mass were measured with a weighing machine based on calculating torques. with respect to the multivariate regression assumptions and stepwise method, the variables that had the greatest impact on the center of mass were selected and models were proposed whit them. Results: The girl&rsquo;s equation, shows that the stature, body mass index and sitting height per stature ratio, can be used to estimate the center of mass of girl children, and the estimated center of mass for boy children, with stature, sitting height and sitting height per stature ratio, form equation is possible. Conclusion: It is recommended to use the obtained equations in order to estimate the center of mass of children's bodies, rather than using multiple and sometimes difficult, time-consuming and costly methods and calculations. Conclusion: It can be said that, in order to calculate the center of mass of child, instead of using multiple and sometimes difficult, time consuming and costly methods and calculations, the equations obtained in this study should be used

A Study on the Selected Anthropomorphic Characteristics of Girls and Boys in Childhood and Adolescence

Introduction: The structural body features provide physicians, health care professionals, educators, and parents with important information like natural body development, physical activities in accordance through body size, sport talent identification, and prediction of certain diseases such as cardiovascular and cancer problems. This study was run to determine and compare the features of average body stature as height at both lying and standing positions, sitting height, and sitting height to standing height ratio. Materials and methods: Among 315,987 elementary to high school students in Isfahan City, Iran, 768 children and adolescents were selected through cluster sampling, and were categorized in four groups, according to age and gender. Postural variables were measured using a standard meter. To describe and analyze the data, one-way ANOVA, Levene, and Post Hoc tests were run at a significance level of less than 0.05. Results: Although lying height was higher than standing height, their increasing trends remained the same. Although the boys’ sitting height was higher than the girls’, the sitting height to standing height ratio of the boys was lower than girls. Adolescent girls and boys had the most and the least sitting height to standing height ratio, respectively. Sitting height to standing height ratio was different in each category (P < 0.001 for all). Conclusion: There was no significant difference in the mean lying height, standing height, and sitting height between boy and girl children. As to the sitting height to standing height ratio, girl adolescent with both boy and girl children were at the same level, and boy adolescent were on another. The findings have correspond to standards of Centers Disease Control and Prevention (CDCs) for height

Effects of Ethanol on the Expression Level of Various BDNF mRNA Isoforms and Their Encoded Protein in the Hippocampus of Adult and Embryonic Rats

We aimed to compare the effects of oral ethanol (Eth) alone or combined with the phytoestrogen resveratrol (Rsv) on the expression of various brain-derived neurotrophic factor (BDNF) transcripts and the encoded protein pro-BDNF in the hippocampus of pregnant and embryonic rats. A low (0.25 g/kg body weight (BW)/day) dose of Eth produced an increase in the expression of BDNF exons I, III and IV and a decrease in that of the exon IX in embryos, but failed to affect BDNF transcript and pro-BDNF protein expression in adults. However, co-administration of Eth 0.25 g/kg·BW/day and Rsv led to increased expression of BDNF exons I, III and IV and to a small but significant increase in the level of pro-BDNF protein in maternal rats. A high (2.5 g/kg·BW/day) dose of Eth increased the expression of BDNF exons III and IV in embryos, but it decreased the expression of exon IX containing BDNF mRNAs in the maternal rats. While the high dose of Eth alone reduced the level of pro-BDNF in adults, it failed to change the levels of pro-BDNF in embryos. Eth differentially affects the expression pattern of BDNF transcripts and levels of pro-BDNF in the hippocampus of both adult and embryonic rats

Performance evaluation of road base stabilized with styrene–butadiene copolymer latex and Portland cement

This study investigated the effects of the addition of a carboxylated styrene–butadiene emulsion (Tylac® 4190) and Portland cement on the long-term performance of road base. To achieve the goals of this study, a literature review, laboratory investigation, and data processing and analyses were accomplished. The specimens stabilized with Portland cement (0–6%) and Tylac® 4190 (5–10%) and subjected to different stress sequences in order to study the unconfined compressive strength, flexural strength, soaked and unsoaked California bearing ratio, dynamic creep, and wheel-tracking characteristics of 7-day-cured specimens. The permanent strain behavior of the samples was assessed by the Zhou three-stage creep model. The results of dynamic creep and wheel-tracking tests showed that the permanent deformation characteristics were considerably improved by the addition of a 4% Portland cement–8% Tylac® 4190 mixture, which resulted in reduction of permanent strain of the mixture. The use of the 4% cement–8% Tylac® 4190 mixture increased the flexural strength by 81.4% and 288.2% as compared to the use of 4% cement and 8% Tylac® 4190, respectively. Keywords: Road base, Long-term performance, Stabilized, Wheel tracking, Permanent strain, Polyme