Karakteristik Membran Asimetris Polietersufone (PES) Dengan Pelarut Dimetil Formamide Dan N-Metil-2-Pyrolidone - (Characteristic of Poliethersulfone (PES) Asymmetric Membrane with Dimethyl Formamide and N-Methyl Pyrolidone as Solvent)

Membrane that is generally used for separation process could be made using phase inversion technique. This research aims to create polyethersulfone (PES) asymmetric membranes via phase inversion technique using solvent and Trans Membrane Pressure (TMP) as variable. SEM analysis indicated that membranes had asymmetric structure that consits of two layers which denser skin layer on the top surface and the porous support on the bottom. PES/DMF membrane showed larger pore structure than PES/NMP. The permeability coefficients of both membranes were in the ultrafiltration range. The coefficient permeability (Lp) of PES/DMF membrane was 35.769 L/m2.hour, much greater compared to PES/NMP membrane which was 15.364 L/m2.hour.bar. Molecular Weight Cut-Off (MWCO) of PES/DMF membrane was 177 Kda, meanwhile PES/NMP was 186 Kda. Performances of the membranes were evaluated using dextrane as feed solution. PES/DMF membrane resulted in an higher flux and lower rejection than PES/NMP

Enhancement of flexibility in multi-energy microgrids considering voltage and congestion improvement: Robust thermal comfort against reserve calls

In recent years, multi-energy microgrid (MEM) has gained increasing interest, which could use clean and efficient electro-thermal resources, multi-energy storages (MESs) and demand response potential to improve the flexibility of MEM. However, maximizing the flexibility potential of MEM and alongside managing the electrical parameters (EPs) is a challenging modeling problem. In this paper, a probabilistic nonlinear model is presented to maximize the flexibility with all the power grid constraints taking into account EPs constraints using power flow. To this end, voltage profile and congestion improvement, robust thermal comfort provision during reserve call and MESs utilization are the key properties of the proposed model. The outcome of suggested model ensures sustainability in the MEM performance, which is an essential feature in modern smart cities. The presented model is applied to a distribution network in the UK and results illustrate how equipment scheduling and demand response leads to observe the EPs limitation and maximizes MEM flexibility. The achieved results show a decrease in MEM revenue (decrease of 34% and 24% without and with reserve commitment, respectively) and in contrast, a significant increase in flexibility compared to non-compliance with EPs constraints

Removal of heavy metals from textile wastewater using sugarcane bagasse activated carbon

Excessive release of textile wastewater with heavy metals into environment has posed a great problem to the natural water system. The efficiency of the adsorption process to remove heavy metals depend on the adsorbent. The commercial activated carbon is one of the most efficient adsorbent, but the limitation lies in the high cost. Therefore, the present study aimed to investigate the efficiency of sugarcane bagasse activated carbon modified by phosphoric acid as adsorbent for the removal of zinc (Zn) and Ferum (Fe) from the textile wastewater. The adsorption process was conducted using batch method as a function for pH (2-7), contact time (30 min to 24 h) and adsorbent dosage (0.6 to 6g). The final concentrations of the metal ions were determined by ICP-MS. The results revealed that the adsorption efficiency increased with the contact time, the optimum time was recorded after 2 h. The removal percentage of Zn and Fe associated with the adsorbent dosage due to the greater surface area with optimum value of 4.0 g. The increasing of pH from 2 to 6 correlated with high adsorption efficiency, with the optimum condition at pH 5. The maximum percentage removal of Fe, Zn was 80%. These findings indicated that the SBAC is an attractive alternative adsorbent material for the metal ions removal in textile wastewater

Measuring students’ understanding in counting rules and its probability via e-learning mode: a Rasch measurement approach

Probability is a study of the rules that offers the foundational theory for the development of statistics. This sets out the investigation where students’ understanding of counting rules and its probability were explored using the Rasch measurement approach. A test instrument with 20 items was developed and administered to 74 students taking the STA150 Probability and Statistics course. Data were captured through an interactive e-learning platform that is dmodo.com and analyzed using Winsteps 3.81.0. The results from the Wright map showed that 83.8% of the students have the ability that matched well with the difficulty of the while 16.2% of the students need to be given more attention on the topic. The study was also able to show that the items can be replicated in other samples of similar characteristics. Keywords: students’ understanding; counting rules; probability Raschmeasurement model; Wright map

Quantification of cardiac capillarization in single-immunostained myocardial slices using weakly supervised instance segmentation

Decreased myocardial capillary density has been reported as an important histopathological feature associated with various heart disorders. Quantitative assessment of cardiac capillarization typically involves double immunostaining of cardiomyocytes (CMs) and capillaries in myocardial slices. In contrast, single immunostaining of basement membrane components is a straightforward approach to simultaneously label CMs and capillaries, presenting fewer challenges in background staining. However, subsequent image analysis always requires manual work in identifying and segmenting CMs and capillaries. Here, we developed an image analysis tool, AutoQC, to automatically identify and segment CMs and capillaries in immunofluorescence images of collagen type IV, a predominant basement membrane protein within the myocardium. In addition, commonly used capillarization-related measurements can be derived from segmentation masks. AutoQC features a weakly supervised instance segmentation algorithm by leveraging the power of a pre-trained segmentation model via prompt engineering. AutoQC outperformed YOLOv8-Seg, a state-of-the-art instance segmentation model, in both instance segmentation and capillarization assessment. Furthermore, the training of AutoQC required only a small dataset with bounding box annotations instead of pixel-wise annotations, leading to a reduced workload during network training. AutoQC provides an automated solution for quantifying cardiac capillarization in basement-membrane-immunostained myocardial slices, eliminating the need for manual image analysis once it is trained

A suggested prototype for assessing bone health

Background- Osteoporosis is becoming a health concern worldwide. Considering the fact that prevention plays an important role in reducing the burden of this silent disease and in view of the limited resources available, many countries have adopted certain programs to fight osteoporosis through shifting their attention towards at-risk individuals. The Iranian Multicenter Osteoporosis Study (IMOS) is one of these programs. The program aims to assess bone health and the prevalence of vitamin D deficiency in different parts of Iran with various altitudes, latitudes and lifestyle habits in a way that the results could be generalized to the country. Method- The present article presents the protocol used in the third phase of the study. It was designed based on the experiences gathered in the previous phases to overcome the shortcomings particularly subject loss. The questionnaire applied in this study was developed based on a thorough literature review of the risk factors and secondary causes of osteoporosis and was approved by an expert panel. It should be added that while the majority of the existing studies aim to study a certain aspect of osteoporosis, the present protocol provides the information needed for policy makers and researchers to study different osteoporosis-related issues. Conclusion- The authors believe the protocol, to be implemented with small modifications, can help policymakers in different parts of the world, particularly developing countries, gather accurate information on different aspects of bone health at the national level. © 2015, Academy of Medical Sciences of I.R. Iran. All rights reserved

Characteristic and Performance Tests of Membrane PES in Biodiesel Purification by Using Ultrafiltration Process

Polyethersulfone (PES) membranes were prepared via phase inversion method. The effect of polymer concentration on the morphology of the fabricated membranes were studied. Furthermore, the effect of transmembrane pressure (TMP)was also studied on the filtration performance of biodiesel purification. The morphology of fabricated PES membrane was analyzed by using Scanning Electron Microscopy (SEM) indicated that the PES membranes had skin layer on the membrane surface and pores layer on the bottom surface. The permeability coefficient (Lp) of PES membranes were about 21-40 L/m2.h. The Molecular Weight Cut Off (MWCO) test shows that the rejection of dextran solution with the molecular weight 18,8Kda was above 90%. The water contact angle of PES membranes was measured to know the hydrophilicity of PES membrane. The water contact angle was about 73oconfirmed that the PES membrane was hydrophobic. The increasing ofTrans-membrane Pressure (TMP) had a significant effect on the permeability of membrane which isthe permeability of biodiesel increases by increasing the TMP. The maximum of flux was obtained about 110 ml/se

Technical competencies of oil and gas construction project managers in Malaysia

The oil and gas business is one of the most important and largest industries in the world. Despite the industry's large economic contribution, the output of major projects has not met expectations, particularly with regard to cost and schedule goals. project managers should possess sufficient technical knowledge and skill to perform their jobs, especially in the oil and gas industry. This paper aims to assess the level of technical competencies for oil and gas construction project managers in Malaysia.Data were collected from 75 respondents from different organisations that are involved with oil and gas construction projects in Malaysia by using a questionnaire. The current level of construction project managers in the oil and gas construction in Malaysia are mostly competent and have the most satisfied rating in determining appropriate construction methods, followed by project scheduling, directing and monitoring the project's progress. Hopefully, this study can help the industry sector, especially in oil and gas, to find competent technical PMs to ensure the project can be delivered well