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2022 ◽  
Vol 36 ◽  
pp. 100747
Author(s):  
Antoon JB ten Kate ◽  
Patrick M Piccione ◽  
Peter Westbye ◽  
Antonio F Amado Becker

Nanomaterials ◽  
2022 ◽  
Vol 12 (2) ◽  
pp. 277
Author(s):  
Miral Al Sharabati ◽  
Rana Sabouni ◽  
Ghaleb A. Husseini

Metal−organic frameworks (MOFs) are a novel class of porous hybrid organic−inorganic materials that have attracted increasing attention over the past decade. MOFs can be used in chemical engineering, materials science, and chemistry applications. Recently, these structures have been thoroughly studied as promising platforms for biomedical applications. Due to their unique physical and chemical properties, they are regarded as promising candidates for disease diagnosis and drug delivery. Their well-defined structure, high porosity, tunable frameworks, wide range of pore shapes, ultrahigh surface area, relatively low toxicity, and easy chemical functionalization have made them the focus of extensive research. This review highlights the up-to-date progress of MOFs as potential platforms for disease diagnosis and drug delivery for a wide range of diseases such as cancer, diabetes, neurological disorders, and ocular diseases. A brief description of the synthesis methods of MOFs is first presented. Various examples of MOF-based sensors and DDSs are introduced for the different diseases. Finally, the challenges and perspectives are discussed to provide context for the future development of MOFs as efficient platforms for disease diagnosis and drug delivery systems.


Author(s):  
Jannik Burre ◽  
Dominik Bongartz ◽  
Alexander Mitsos

AbstractSuperstructure optimization is a powerful but computationally demanding task that can be used to select the optimal structure among many alternatives within a single optimization. In chemical engineering, such problems naturally arise in process design, where different process alternatives need to be considered simultaneously to minimize a specific objective function (e.g., production costs or global warming impact). Conventionally, superstructure optimization problems are either formulated with the Big-M or the Convex Hull reformulation approach. However, for problems containing nonconvex functions, it is not clear whether these yield the most computationally efficient formulations. We therefore compare the conventional problem formulations with less common ones (using equilibrium constraints, step functions, or multiplications of binary and continuous variables to model disjunctions) using three case studies. First, a minimalist superstructure optimization problem is used to derive conjectures about their computational performance. These conjectures are then further investigated by two more complex literature benchmarks. Our analysis shows that the less common approaches tend to result in a smaller problem size, while keeping relaxations comparably tight—despite the introduction of additional nonconvexities. For the considered case studies, we demonstrate that all reformulation approaches can further benefit from eliminating optimization variables by a reduced-space formulation. For superstructure optimization problems containing nonconvex functions, we therefore encourage to also consider problem formulations that introduce additional nonconvexities but reduce the number of optimization variables.


2022 ◽  
Vol 67 (1) ◽  
pp. 1-2
Author(s):  
J. Ilja Siepmann ◽  
Ramesh Gardas ◽  
David A. Kofke ◽  
Carlos Nieto de Castro ◽  
Eugene Paulechka ◽  
...  

Author(s):  
Muhammad Yasir ◽  
Awais Ahmed ◽  
Masood Khan ◽  
Zahoor Iqbal ◽  
Muhammad Azam

The most important and significant research topic in mechanical and industrial engineering is the fluid flow with heat transport by a stretched surface because of the numerous applications. The impact of heat transport on product quality can be noticed in the field of chemical engineering, polymer processing, glass fiber production, hot rolling, metal extrusion, production of paper, and drawing of plastic films and wires. In light of such foregoing applications, an attempt is made to model the thermal and solutal diffusion phenomena in Oldroyd-B nanofluid flow over a stretching cylinder by using Buongiorno's model and Cattaneo-Cristov theory. To explore the heat flow mechanism in the flow, the effects of heat source/sink with ohmic heating are also considered. Additionally, the influence of chemical reactions is used to investigate the solutal transport process in nanofluid flow. The mathematical formulation section of the manuscript depicts the mathematical modeling of momentum, heat, and mass diffusion equations. The effect of dimensionless physical constraints on the flow, temperature, and concentration distributions of Oldroyd-B nanofluid flow are investigated using the homotopy analysis method (HAM) in Wolfram Mathematica. In the results and discussion section, graphical findings are displayed and physically justified. A section of concluding remarks is added at the end of the text to emphasize the study's major findings.


2022 ◽  
pp. 18-25
Author(s):  
HONGJUAN WANG ◽  
WEI HU ◽  
OLENA SALIY

Purpose. Study pore size effect and morphology of mesoporous silica on metoprolol tartrate release.Methodology. A sample of hollow mesoporous silicon dioxide with amino-functional groups containing 12.7 wt. % metoprolol tartrate has been investigated as potential carriers for the controlled release of active substance. Studies of the release profiles of metoprolol tartrate were performed under the following conditions: dissolution medium was buffer solution with a pH of 7.4 (phosphate buffer); sampling time: from 0.5 h before 18 h. The metoprolol concentration in the liquid phase was evaluated by a UV-Vis spectrophotometer (Persee TU-190, Beijing, China) by use of quartz cuvettes with an optical path length of 1 cm at a maximum wavelength of 274 nm.Findings. In this work we have studied mesoporous silica as possible carrier to controlled release of metoprolol tartrate, a drug used in the treatment of some diseases of the cardiovascular system. The material for research was a sample of hollow mesoporous silicon dioxide with amino-functional groups 200–400 nm in size and 20–30 nm in shell thickness. A calibrated curve to determine the amount of metoprolol was constructed by determining the absorption dependence of the concentration of metoprolol in the range from 10 to 300 ppm. The same drug concentration was obtained as calculated from the drug release test formula, which concludes that the release of metoprolol is controlled.Originality. The controlled release of a sample of hollow spheres of mesoporous silicon dioxide filled with metoprolol tartrate was studied, which was synthesized by the School of Chemistry and Chemical Engineering, Qilu University of Technology, using a new technology, where hollow spheres of mesoporous silicon dioxide with amino groups were synthesized using CO2 gas bubbles as templates.Practical value. The metoprolol release amount could achieve a 50% release amounts within 1 hour and 90% within 5 hours, indicating that the synthesized mesoporous hollow sphere could achieve controlled drug release, and shows the potential of carriers with stimulus response and targeted therapy.


Athenea ◽  
2022 ◽  
Vol 2 (6) ◽  
pp. 28-42
Author(s):  
Alberto Echegaray

This article presents an approach to the problem of ceramic types adhesion, applying energy and matter balance to the established control volume (cyclone) with the use of mathematical formulas that are interrelated to develop mathematical calculations and establish a new mathematical model The first results are obtained by operating the energy balance considering the collision of particles, using the principle of conservation of energy, the first law of thermodynamics, in order to obtain information that allows describing the phenomena of thermoplasticity and creep, in the formation of adhesions, from a physicochemical and kinetic point of view, which will serve as the basis for understanding their effect. As a result, an energy value of 660 kJ / mol was obtained, sufficient energy to start the transformation of the solid particles to a state of thermo-flow that allows the adhesion phenomenon to be started. Keywords: Adhesion, energy balance, cyclones, elutriation, eutectoid, fayalite, thermoplasticity. References [1]O. Bustamante. “Dissipation of mechanical energy in the discharge of a hydrocyclone”. (Dyna, Ed.) The network of Scientific Journals of Latin America, the Caribbean, Spain, and Portugal, vol. 80 (181), Pages 136-143, 2013. [2]K.Petersen, P.Aldrich, and D.Van.,”Hydrocyclone underflow monitoring using image processing methods. Minerals Engineering”, pp. 301-315,1996. [3]M. Farghaly,” Controlled Wash Water Injection to the hydrocyclone underflow” [Ph.D. Thesis]. Erlangen, FAU, 2009. [4]M, Schneider, and T. Neesse. “Overflow-control system for a hydrocyclone battery. Int. J. Miner. Process". 74, pp. 339 – 343, 2004. [5]J.Bergström., “Flow field and fiber fractionation studies in hydro cyclones” [Ph.D. Thesis] Stockholm, Sweden, Royal Institute of Technology, 2006. [6]C, Liu, L. Wang, and Q. Lui., “Investigation of energy loss mechanisms in cyclone separators”. Chemical Engineering Technology 28, pp. 1182-1190, 2005. [7]O.Dam. & E.Jeffes.,.”Model for detailed assessment of chemical composition of reduced iron ores from single measurement”. Ironmaking and Steelmaking, 1987. [8]E. Ringdalen., “Softening and melting of SiO2 an important parameter for reactions with quartz in Si production” pp 43-44, 2016.


2022 ◽  
Vol 9 ◽  
Author(s):  
Banan Hudaib ◽  
Ali F. Al-shawabkeh ◽  
Fadia Hudaib

Background and Objectives: On March 11, the World Health Organization stated coronavirus disease 2019 (COVID-19) was a global pandemic; the rapid and extended spread of the COVID-19 pandemic has become a significant cause of concern for face-to-face university study. This study investigated the knowledge and awareness of chemical engineering students in Al-Balqa Applied University (BAU) in Jordan about respiratory protective measures against COVID-19.Materials and Methods: A cross-sectional study was developed using a multi-stage random sampling technique conducted from April 21–28, 2020. The data were collected through an online questionnaire distributed to BAU's chemical engineering students, with 179 responders completed the survey correctly. The data were analyzed statistically using the SPSS program. The questionnaire consisted of two parts: the first measured the student's general knowledge about the COVID-19 pandemic, while the second focused on the respiratory protection methods against COVID-19; it was structured to assess the student's knowledge about the suitable types of masks and respirators used in COVID-19 prevention, their detailed mechanism of action and filtration process type, their production materials, and finally how the student's knowledge affects choosing a proper preventive method.Results: The study found moderate awareness among engineering students about COVID-19 causative agent, effective preventive masks/respirators used, and the mask's viral blockage mechanisms. A total of 89 respondents (49.7%) pointed to the correct best protective mask, i.e., N95 mask. On the other hand, 119 respondents (66.5%) believed that a surgical mask is the best protective mask. The study also showed differences in knowledge between different academic years; the knowledge about respirators, masks, and their action mechanism among senior students in the last three academic years was better than the younger students with a P-value of 0.047 for knowledge about respirator used for protection against coronavirus disease and the P-value of 0.028 for knowledge of the comparisons between the N95 and surgical mask. On the other hand, the study showed a lack of awareness of the most suitable mask types used in pandemics and the appropriate use method.Conclusions: The study found that chemical engineering students in Al-Balqa university were moderately knowledgeable regarding COVID-19 respiratory preventive methods; these results provided an overview of each student's community's knowledge level. Therefore, efforts are needed to improve public awareness through comprehensive educational campaigns to increase students' knowledge, attitude, and practice.


2022 ◽  
Vol 43 (2) ◽  
Author(s):  
Dzmitry H. Zaitsau ◽  
Sergey P. Verevkin

AbstractNew experimental vapor pressures in the range 407 K to 460 K and vaporization enthalpy of the ionic liquids (IL) N-alkyl-N-methyl-pyrrolidinium bis(fluorosulfonyl)imide ionic liquids have been measured using quartz crystal microbalance. The absolute vapor pressures and vaporization enthalpies were compared with analogous pyrrolidinium-based ILs with the bis(trifluoromethanesulfonyl)imide anion. The evaluated difference in vaporization enthalpy of ILs with bis(fluorosulfonyl)imide and bis(trifluoromethanesulfonyl)imide anions allowed for estimation of corresponding property for a wide set of ILs with bis(fluorosulfonyl)imide anion. The results are relevant to chemical engineering calculations of processes involving ILs as reaction and separation media.


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