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Where precision is paramount in managing temperature and fluid dynamics, micro heat exchangers (MHXs) emerge as indispensable tools. This review investigates the significance of MHX technology, offering readers a comprehensive roapmap from conceptualization to market application. We dissect the nuances of material selection, shedding light on cutting‐edge advancements poised to revolutionize MHX efficiency. Furthermore, we explore how the geometry of MHX influences heat transfer dynamics and pressure drop, providing insights into enhancing the overall effectiveness. We delve into the various types of control instrumentation, offering a detailed analysis of their applicability. Beyond the technical prowess, the economic landscape plays a pivotal role in the adoption of MHX technology. [ABSTRACT FROM AUTHOR]

The synergy of integrating semiconductors and MOF photocatalysts is the chief motive for this review paper. This merit has been combined with the microfluidic platforms, which are the cutting‐edge technology of synthesis. The microfluidic synthesis of semiconductors and MOF photocatalysts are categorized according to morphology and linker, respectively. Enhancing the effectiveness of photocatalysis comes along with adding a proper amount of electron acceptor or hole scavenger, combing electrochemical with photocatalytic degradation, and optimizing the photocatalyst band gap. Moreover, approaches for improving photocatalytic activity of MOFs can be classified as functionalization of organic linkers/metal centers, sensitization, incorporation of nanoparticles, and hybridization with semiconductors. Finally, the current applications of microfluidic devices, from the detection of water quality parameters to the elimination of water contaminants, have been addressed. [ABSTRACT FROM AUTHOR]

Inexpensive and new adsorbents, which are produced by processing the abundant agricultural by-products, can provide an efficient solution for a cleaner environment. The occurrence of heavy metals in water may pose a significant threat to human health. In this work, the processed date kernels are used to remove chromium (VI) and iron (III) from water. The XRD, FTIR, SEM, VSM and EDX techniques are used to characterize the adsorbents. The equilibrium adsorbent dose for iron is 2 g/L while for chromium (VI) it is 4 g/L and the equilibrium time is 20 min. Moreover, acidic conditions favored the adsorption for both targets. The adsorption experiments showed that the kinetics of adsorption of chromium (VI) and iron (III) on date kernel powder fitted the pseudo-second-order model. The optimum adsorption capacities for iron (III) and chromium (VI) are 10.5 mg/g and 0.66 mg/g, respectively. In the meantime, the remarkable efficiency of the date kernel-based adsorbent for iron (III) removal paves the way for designing new magnetic adsorbents. [ABSTRACT FROM AUTHOR]

Background: Learning experiences help learners achieve educational goals and are usually related to the educational context that occurs in teaching groups, teacher-student relationships, and teaching-learning activities. Objectives: The current study aimed to explain the views of non-Iranian students on the quality of learning experiences at Shahid Beheshti University of Medical Sciences, Tehran, Iran. Methods: This was a qualitative study with the directional content analysis method. The participants were 12 non-Iranian students studying in the last year or before the last year inmedicine, nursing, and paramedical faculties of Shahid Beheshti University of Medical Sciences who were randomly selected from non-Iranian students for semi-structured oral interviews. The interviews continued until data saturation. Results: After content analysis, 85 initial codes were extracted. Based on the relationship between the codes, 14 subcategories were obtained and placed into 4 main categories. The main categories were available resources, available content, learning flexibility, and the quality of professors’ relationships with students. Conclusions: Based on the results, the quality of learning experiences plays a critical role in effective learning. Paying attention to the experiences and viewpoints of non-Iranian students studying at Shahid Beheshti University of Medical Sciences is very important to improve the quality of learning experiences and attract non-Iranian students. [ABSTRACT FROM AUTHOR]

For the first time, a bio-photo-catalyst is synthesized in a microfluidic platform. The microchannel, which is wall-coated by in situ synthesized bio-photo-catalyst is used as an opto-fluidic reactor for amoxicillin degradation. Analyses including SEM, XRD, FTIR, Raman, UV–Vis spectra, and DLS have been used to characterize samples. The structure and morphology of TiO2 in microfluidic assisted synthesis are studied at 70–120 °C. The results show that both single-crystalline anatase sample and two-phase samples of anatase and rutile can be attained. According to SEM images, the smallest size and the narrowest particle size distribution (0.86 nm ± 0.14 ) is achieved by synthesis at 70 °C. Elemental mapping of Ti shows a uniform coating layer on inner walls. Raman signals besides the primary amines in FTIR results show the biological activity of the cross-linked Glucose oxidase (GOx), which is aimed for situ generation of H2O2. FTIR comparison of bulk and spiral microfluidic synthesized ZnO indicates identical bonds. SEM-coupled with performance experimentation reveal that by regulating the flowrate of spiral micromixer for ZnCl2 at 25 µl/min and NaOH at 50 µl/min, the narrowest size distribution and best the bio-photo-catalytic performance of ZnO nanoparticles is observed. [ABSTRACT FROM AUTHOR]

This review paper is devoted to the intensification of processes for nitrate removal. First, the developments of microfluidic sensors for nitrate detection and analysis have addressed. Second, the process variables of photocatalytic nitrate removal have been categorized according to their relationship with activity, selectivity and stability of the catalyst. The objective of this classification is to generate guidelines toward the photocatalytic process optimization. Third, because of the fact that a single method for nitrate removal faces some challenges, hybrid methods have been presented, and the best choice for nitrate removal can be referred to as photocatalytic – reverse osmosis method. Finally, brine management strategies have also been stated. [ABSTRACT FROM AUTHOR]

Microfluidics is an emerging branch of science that has significant applications in various fields. In this review paper, after a brief introduction to the concept of photocatalysis, nanoparticle preparation methods and film formation techniques have been studied. Nanoparticle synthesis in microfluidic systems and microreactor types for on-chip photocatalyst synthesis and challenges of nanoparticles handling in microsystems have been reviewed. To resolve particle polydispersity and microchannel clogging, a good suggestion can be the use of droplet-based microreactors. The configurative designs for the microfluidic reactor with immobilized photocatalysts, their applications, and their challenges have been comprehensively addressed. The three main challenges ahead the immobilized photocatalytic microfluidic reactors are optimal light distribution, prevention of the recombination of photogenerated electrons and holes, and improved mass transfer. Internal light-emitting diodes with a waveguide can resolve the number one challenge of photocatalysis application in optofluidic reactors, that is, light distribution. [ABSTRACT FROM AUTHOR]

Aim: The study aimed to formulate solid lipid nanoparticles (SLNs) for the transdermal delivery of PPL to improve skin retention and efficacy., Materials and Method: The particle size distribution of SLNs was determined and the morphology of SLNs was also analyzed by SEM. In-vitro , ex-vivo and in vivo evaluations were done for PPL loaded SLN. The safety of drug delivery systems was assayed using MTT test., Results: The results indicated successful encapsulation of PPL in SLNs (59.38%), which exhibited a spherical shape and smooth surface. Compared to PPL solution, SLNs demonstrated a prolonged drug release profile in vitro . Stability tests over three months showed no significant changes in entrapment efficiency or size distribution. Enhanced permeation through shed snake and rat skin was observed with SLNs compared to the PPL solution. Ex-vivo and in vivo studies confirmed that PPL-loaded SLNs significantly increased drug content in the skin. Importantly, the SLNs displayed biocompatibility, as no significant cytotoxic effects were noted, and they were nonirritating to rat skin., Conclusion: To the best of our knowledge, this is the first study that indicates SLNs can be considered as a promising nanocarriers for transdermal delivery of PPL.