Coagulation Of Wood Pollutants From Model Wastewater By Aluminium Salts

One of the stages of raw material preparation for plywood producing is hydrothermal treatment of birch wood. Wastewater from plywood hydrothermal basin is characterized by the high degree of contamination. The basic contaminating component of this wastewater is lignin, hemicellulose and extractive substances (LES), which are the main reason of a high level of chemical oxygen demand (COD) and color of water. The main objective of the present study is to investigate the influence of aluminium sulfate, aluminium chloride and poly aluminium chloride dose on coagulation of LES from model wastewater. It was established that the influence of coagulant dose on LES removal can be described by 3 regions: first region - the process of coagulation does not take place; second region is characterized by the sharp increase of efficiency of LES removal and the third region corresponds to decrease of efficiency of LES removal at the increase of coagulant dose

Influence of waste glass in the foaming process of open cell porous ceramic as filtration media for industrial wastewater

This paper reports the development and testing results of a prototype ceramic filter with excellent sorption properties (<99% elimination in 5 min) leading to good efficacy in the removal of industrial contaminants (Reactive Bezaktiv Turquoise Blue V-G (BTB) dye). The novelty in the investigation lies in developing the filter material obtained from the recycling of waste glass combined with highly porous open-cell clay material. This newly developed material showed a significant reduction in the energy requirements (sintering temperature required for the production of industrial filters) thus addressing the grand challenge of sustainable and cleaner manufacturing. The methodology entails sintering of the clay foam (CF) at temperatures ranging from 800 to 1050 °C and blending it with 5%, 7% and 10 wt% milled glass cullet. One of the aims of this investigation was to evaluate and analyse the effect of the pH of the solution, contact time and equilibrium isotherm on the sorption process and the mechanical compressive strength, porosity, water uptake. From the kinetic studies, it was discovered that the experimental results were well aligned with the pseudo-second-order model and chemisorption was discovered to be a mechanism driving the adsorption process. These findings are crucial in designing cost-effective industrial filtration system since the filter material being proposed in this work is reusable, recyclable and readily available in abundance. Overall, the pathway for the reuse of waste glass shown by this work help address the sustainability targets set by the UN Charter via SDG 6 and SDG 12

The advanced application of the wood-originated wastewater sludge

The wood hydrothermal treatment is one of the plywood production’s stages, which resulting in the production of wastewater containing such components as hemicelluloses, lignin and wood extractive substances (HLES). It is necessary to improve the wastewater treatment technology with the aim to enhance the yield of sludge from plywood wastewater for its effective and rational recycling. In the present study, the optimal coagulation conditions for the HLES removal have been found using the developed aluminium salt-based coagulant. The developed composite coagulant is characterized by lower doses, a wide range of the work pH values, the insensitivity against temperature changes and a higher coagulation efficacy compared with traditional aluminium salts. The proposed treatment technology generates many tons of woodoriginated sludge – a biomass coagulate. It was found that the formed coagulate produced in the process of wastewater treatment can increase the sorption ability of clay. The optimal content of the dry coagulate in a clay sorbent does not exceed 0.11%. The sorption capacity of the developed sorbent for water, rapeseed and silicone oil increases by 35%, 31% and 21%, respectively, relative to the unmodified clay sorbent. The sorption efficiency of heavy metals from water solutions is also increased by 10–12%. The thermal treatment of the modified clay sorbent at the high temperature leads to an increase in its sorption capacity for oil products

Fibrinolytic system changes in liver surgery : A pilot observational study

Publisher Copyright: © 2018 Ozolina, Nemme, Ozolins, Bjertnæs, Vanags, Gardovskis, Viksna and Krumina.Introduction: Bleeding occurs frequently in liver surgery. Unbalance between tissue plasminogen activator (t-PA) and plasminogen activator inhibitor-1 (PAI-1) concentrations might increase bleeding. Our aim was to analyze perioperative fibrinolytic changes during liver surgery. Materials and Methods: We evaluated 15 patients for inclusion into a prospective pilot study of liver surgery. We assessed fibrinolysis by plasma PAI-1 and t-PA: before surgery (T1), before Pringle maneuver (PM;T2), at the end of surgery (T3) and 24 h postoperatively (T4), and registered demographic and laboratory data, extent and duration of surgery, hemodynamic parameters, blood loss, and transfused volumes of blood products. Data presented as mean ± SD. Significance at P < 0.05. Results: After exclusion of six patients only undergoing biopsies, we included six women and three men aged 49.1 ± 19.6 years; two patients with liver metastases of colorectal cancer and hepatocellular carcinoma, respectively, two with focal nodular hyperplasia, two with hepatic hemangioma, and one with angiomyolipoma. Six patients underwent PM. PAI-1 plasma concentration (n = 9) rose from 6.25 ± 2.25 at T1 through 17.30 ± 14.59 ng/ml at T2 and 28.74 ± 20.4 (p = 0.007) and 22.5 ± 16.0 ng/ml (p = 0.04), respectively, at T3 and T4. Correspondingly, t-PA plasma concentration (n = 9) increased from 4.76 ± 3.08 ng/ml at T1 through 8.00 ± 5.10 ng/ml (p = 0.012) at T2 and decreased to 4.25 ± 2.29 ng/ml and 3.04 ± 3.09 at T3 and T4, respectively. Plasma t-PA level at T2 was significantly different from those at T1, T3, and T4 (p < 0.004). In PM patients, t-PA levels increased from T1, peaked at T2 (p = 0.001), and subsequently decreased at T3 and T4 (p = 0.011 and p = 0.037), respectively. Mean blood loss was 1,377.7 ± 1,062.8 ml; seven patients received blood products. Patients with higher PAI-1 levels at T3 received more fresh frozen plasma (r = 0.79; p = 0.01) and red blood cells (r = 0.88; p = 0.002). Conclusions: During liver surgery, fibrinolysis increased, as evidenced by rises in plasma PAI-1and t-PA, especially after start of surgery and following PM. Transfused volumes of blood products correlated with higher plasma concentrations of PAI-1. Confirming this tendency requires a larger cohort of patients.publishersversionPeer reviewe

Self-driven lattice-model Monte Carlo simulations of alloy thermodynamic

Monte Carlo (MC) simulations of lattice models are a widely used way to compute thermodynamic properties of substitutional alloys. A limitation to their more widespread use is the difficulty of driving a MC simulation in order to obtain the desired quantities. To address this problem, we have devised a variety of high-level algorithms that serve as an interface between the user and a traditional MC code. The user specifies the goals sought in a high-level form that our algorithms convert into elementary tasks to be performed by a standard MC code. For instance, our algorithms permit the determination of the free energy of an alloy phase over its entire region of stability within a specified accuracy, without requiring any user intervention during the calculations. Our algorithms also enable the direct determination of composition-temperature phase boundaries without requiring the calculation of the whole free energy surface of the alloy system

Student approaches for learning in medicine: What does it tell us about the informal curriculum?

Extent: 9p.Background: It has long been acknowledged that medical students frequently focus their learning on that which will enable them to pass examinations, and that they use a range of study approaches and resources in preparing for their examinations. A recent qualitative study identified that in addition to the formal curriculum, students are using a range of resources and study strategies which could be attributed to the informal curriculum. What is not clearly established is the extent to which these informal learning resources and strategies are utilized by medical students. The aim of this study was to establish the extent to which students in a graduate-entry medical program use various learning approaches to assist their learning and preparation for examinations, apart from those resources offered as part of the formal curriculum. Methods: A validated survey instrument was administered to 522 medical students. Factor analysis and internal consistence, descriptive analysis and comparisons with demographic variables were completed. The factor analysis identified eight scales with acceptable levels of internal consistency with an alpha coefficient between 0.72 and 0.96. Results: Nearly 80% of the students reported that they were overwhelmed by the amount of work that was perceived necessary to complete the formal curriculum, with 74.3% believing that the informal learning approaches helped them pass the examinations. 61.3% believed that they prepared them to be good doctors. A variety of informal learning activities utilized by students included using past student notes (85.8%) and PBL tutor guides (62.7%), and being part of self-organised study groups (62.6%), and peer-led tutorials (60.2%). Almost all students accessed the formal school resources for at least 10% of their study time. Students in the first year of the program were more likely to rely on the formal curriculum resources compared to those of Year 2 (p = 0.008). Conclusions: Curriculum planners should examine the level of use of informal learning activities in their schools, and investigate whether this is to enhance student progress, a result of perceived weakness in the delivery and effectiveness of formal resources, or to overcome anxiety about the volume of work expected by medical programs.Jianzhen Zhang, Raymond F Peterson and Ieva Z Ozolin