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Application of augmented reality (AR) in education has recently grown in interest due to distant, online, and self-directed learning. In this study, the impact of implementing an AR application on chemical engineering students’ learning motivation and performance was assessed. Two interactive AR lessons on common industrial equipment (i.e., centrifugal pump and shell-and-tube heat exchanger) were developed on the EON-XR platform. A cohort of 50 undergraduate chemical engineering students participated in the AR lessons and evaluated its impact on students’ learning motivation and usefulness as a learning resource. The level of students’ learning motivation was assessed with a 16-item questionnaire based on the Instructional Materials Motivation Survey (IMMS) from Keller’s ARCS model, and qualitative questions related to the future of AR technology in chemical engineering education. Results show that 82% of respondents found AR lessons helpful compared to conventional lesson delivery modes, while 92% were supportive for AR lessons to be an additional resource to existing learning materials. These findings demonstrated that AR technology impacted students’ learning motivation positively across multiple constructs, namely ‘Attention’, ‘Relevance’, ‘Confidence’ and ‘Satisfaction’ and showed great potential as an innovative pedagogical advancement in chemical engineering education. 相似文献
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An attempt has been made to reveal a detailed anatomy of students’ self-perceived engagement with material in a lecture and their learning of a key course threshold concept. A cohort of 80 students in a third year chemical engineering (64% response rate) course voluntarily recorded their engagement using a Likert-type scale at intervals of 5 min in a (nominally 50 min) lecture, together with written comments. Marks were awarded for a substantial, follow-up summative assignment to test their understanding of the threshold concept. It was found students were highly unaligned in their level of engagement with the lecture. A key reason was that individuals’ engagement varied highly significantly during the lecture. Six engagement styles were identified. Some 33% exhibited Type 1 (engage strongly at the start and slowly disengage) and 23% exhibited Type 2 (remain at a more or less fixed engagement). Significantly, there was no correlation between students’ engagement scores and marks awarded; in particular there was no correlation with specific lecture intervals in which material was identified as most important. Further, there was no correlation between the number of written comments made by an individual and their marks. It is concluded that student self-perceived engagement is not a good predictor of learning as assessed by marks awarded on a summative assignment. It is not known whether student engagement is predicated on particular lecture material and type of lecturer, or other contributing factors. The experimental design could be readily widely applied. 相似文献
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Recent reforms in engineering education have emerged to meet the changing needs of engineers, however sparse research exists that comprehensively assesses the outcomes associated with such engineering education efforts. Accordingly, there is an urgent need for educational approaches tied to assessing engineering students’ performance, retention, and impact.This study's purpose is to explore the relationship between sequential chemical engineering degree projects and students’ performance, engineering efficacy, multidisciplinarity, and retention. The projects for this education for chemical engineers research are thematically focused laboratory experiments embedded in a four-year chemical engineering program. Each project component is connected to the next, is increasingly complex as courses advanced, and is aligned with essential course content. This connectivity enables students to participate in logically sequenced experiments that culminate in well-developed senior laboratory projects. This study's educational impact was determined via comparison between seniors’ and freshmen’ performance, efficacy and retention.Results of this research indicate that the use of degree projects in chemical engineering education is impactful, resulting in students’ increased understanding of experimentation and course content; meaningful, resulting in statistically significant increased student chemical engineering efficacy; and engaging, resulting in students’ satisfaction with program impact, engagement with peers during experimentation, and dramatically increased student retention. 相似文献
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Chemical Engineering taught as a subject across three Energy Engineering-based degree streams was evaluated considering two cohorts in two consecutive years after the implementation of the Bologna Process in Spain. A regular continuous assessment methodology yielded negative results during the first year. Student insight on course development, own expectations and results, and the evaluation system were then explored via a 33-item survey with participation levels between 41% and 82%. Direct answers were evaluated including rank correlations between all items. The 465 correlation coefficients obtained showed stimulating and unanticipated results. For example, it was shown that a severe grading process (external blame-assignment) was only identified as an explanation for a low mark by those students who performed most poorly in the subject and, therefore, had a poorer understanding of the materials.Besides, the feedback received from students was used to implement several changes in both the teaching practice and the assessment method during the second year, such as incorporating exam-like problems in daily classes and setting two midterm exams instead of the final one. The results registered after the second year pointed to substantial progress in student learning. Pass rates also rose from a 30% in the first academic year to 49% and 58% in the two following ones. 相似文献
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Juan Eduardo Sosa-Hernández Angel M. Villalba-Rodríguez Kenya D. Romero-Castillo Ricardo Zavala-Yoe Muhammad Bilal Ricardo A. Ramirez-Mendoza Roberto Parra-Saldivar Hafiz M. N. Iqbal 《Polymer Engineering and Science》2020,60(8):1760-1772
Herein, we reviewed polymeric constructs of polyhydroxyalkanoates (PHAs) at large and poly-3-hydroxybutyrate (P3HB), in particular, for drug delivery and tissue engineering applications. Polymeric constructs that can efficiently respond to numerous variations in their surroundings have gained notable attention from different industrial sectors such as biomedical, clinical, pharmaceutical, and cosmeceutical. Among them, considerable importance is given to their drug delivery and tissue engineering applications. PHAs with peculiar reference to P3HB are gaining prominence attention as candidate materials with such requisite potentialities. The unique structural and functional characteristics of PHAs and P3HB are of supreme interest and being used to engineer novel constructs for efficient drug delivery and tissue regeneration purposes. So far, an array of methodological approaches, such as in vitro, in vivo, and ex vivo techniques have been exploited though using different materials with different geometries for a said purpose. However, a low-level production majorly limits their proper exploitation. Various physiochemical characteristics and production strategies have been introduced in this review. The data have been summarized on PHAs production by several microorganisms aiming to cover the scope of the last 10 years. The present review highlights the recent applications of PHAs and P3HB-based constructs, such as micro/nanoparticles, biocomposite, nanofibers, and hydrogels as novel drug carries for regenerative medicine and tissue engineering. In summary, drug delivery and tissue engineering potentialities of PHAs and P3HB-based constructs are discussed with suitable examples and envisioned directions of future developments. 相似文献
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A one-dimensional model published previously for spouted beds is evaluated. Certain errors exist in the governing equations which are modified and corrected in this Letter to Editor. It is confirmed that this is an efficient model as it needs few number of empirical correlations to solve. 相似文献
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I. S. Edelman S. A. Stepanov R. D. Ivantsov T. V. Zarubina E. E. Kornilova A. D. Vasil''ev 《Glass Physics and Chemistry》2001,27(5):454-459
The spectral, field, and temperature dependences of the magnetooptic Faraday effect and the optical absorption spectra in the IR range are measured for potassium aluminoborate glasses doped with iron, manganese, and diamagnetic metal oxides at low concentrations. It is found that the glasses are characterized by high magnitudes of the Faraday rotation and the magnetooptic figure of merit in the spectral range 1.3–1.5 m. The observed magnetooptic and optical properties of glasses are explained by the formation of magnetic-ordered nanosized particles that are similar to manganese ferrite in structure and properties. 相似文献
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Reduction of NO with ammonia in excess oxygen has been carried out on protonform and Cu2+exchanged MFI ferrialuminosilicate. Though HZSM5 showed very low activity, the framework Al in Hferrialuminosilicate greatly enhanced the activity. The framework Al in Cu2+exchanged ferrialuminosilicate also enhanced the activity to some extent. 相似文献
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A luminescent europium metal–organic framework [Eu(HL)(L)(H2O)2]·2H2O (1) (H2L = (2,3-f)-pyrazino(1,10)phenanthroline-2,3-dicarboxylic acid) with uncoordinated phenanthroline nitrogen sites was hydrothermally synthesized. It exhibits highly sensitive and selective sensing of Cu2 + in aqueous solution. To the best of our knowledge, complex 1 is the first luminescent Eu-MOF with uncoordinated phenanthroline nitrogen sites for selective sensing of Cu2 + in aqueous solution. The probable sensing mechanism was discussed in detail. 相似文献
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《Chemical engineering science》1986,41(2):307-315
A new dynamic electrochemical method for the determination of liquid-liquid mass-transfer coefficients in a stirred cell and in a mixer cell is described. Current transients are recorded for different flow conditions and evaluated applying a non-linear regression analysis. The resulting mass-transfer coefficients correlate linearly with the stirring rate but the mean values over a long time period are considerably low. The extent of the investigated initial time dependence of the mass-transfer coefficient decreases with increasing electrolyte concentration. 相似文献
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Hanns-Rudolf Paur Flemming R. Cassee Justin Teeguarden Heinz Fissan Silvia Diabate Michaela Aufderheide Wolfgang G. Kreyling Otto Hänninen Gerhard Kasper Michael Riediker Barbara Rothen-Rutishauser Otmar Schmid 《Journal of aerosol science》2011,42(10):668-692
The introduction of engineered nanostructured materials into a rapidly increasing number of industrial and consumer products will result in enhanced exposure to engineered nanoparticles. Workplace exposure has been identified as the most likely source of uncontrolled inhalation of engineered aerosolized nanoparticles, but release of engineered nanoparticles may occur at any stage of the lifecycle of (consumer) products. The dynamic development of nanomaterials with possibly unknown toxicological effects poses a challenge for the assessment of nanoparticle induced toxicity and safety.In this consensus document from a workshop on in-vitro cell systems for nanoparticle toxicity testing1 an overview is given of the main issues concerning exposure to airborne nanoparticles, lung physiology, biological mechanisms of (adverse) action, in-vitro cell exposure systems, realistic tissue doses, risk assessment and social aspects of nanotechnology. The workshop participants recognized the large potential of in-vitro cell exposure systems for reliable, high-throughput screening of nanoparticle toxicity. For the investigation of lung toxicity, a strong preference was expressed for air–liquid interface (ALI) cell exposure systems (rather than submerged cell exposure systems) as they more closely resemble in-vivo conditions in the lungs and they allow for unaltered and dosimetrically accurate delivery of aerosolized nanoparticles to the cells. An important aspect, which is frequently overlooked, is the comparison of typically used in-vitro dose levels with realistic in-vivo nanoparticle doses in the lung. If we consider average ambient urban exposure and occupational exposure at 5 mg/m3 (maximum level allowed by Occupational Safety and Health Administration (OSHA)) as the boundaries of human exposure, the corresponding upper-limit range of nanoparticle flux delivered to the lung tissue is 3×10?5–5×10-3 μg/h/cm2 of lung tissue and 2–300 particles/h/(epithelial) cell. This range can be easily matched and even exceeded by almost all currently available cell exposure systems.The consensus statement includes a set of recommendations for conducting in-vitro cell exposure studies with pulmonary cell systems and identifies urgent needs for future development. As these issues are crucial for the introduction of safe nanomaterials into the marketplace and the living environment, they deserve more attention and more interaction between biologists and aerosol scientists. The members of the workshop believe that further advances in in-vitro cell exposure studies would be greatly facilitated by a more active role of the aerosol scientists. The technical know-how for developing and running ALI in-vitro exposure systems is available in the aerosol community and at the same time biologists/toxicologists are required for proper assessment of the biological impact of nanoparticles. 相似文献
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《Chemical engineering science》1986,41(2):263-272
Flow of dilute, stable emulsions in porous media is important in several oil recovery processes. Because underground media have relatively low permeabilities, the emulsion drop sizes may overlap the pore sizes. Hence, strong interaction occurs between the emulsion droplets and pore constrictions, and local flow redistribution occurs within the porous medium. To predict quantitatively how emulsions are transported in underground media, a theoretical model is required which correctly accounts for the interactions between the flowing droplets and the pore walls.In Part I of this work, we present a simplified filtration model describing the flow of stable, dilute emulsions in unconsolidated porous media. In the model, emulsion drops are captured in pores by straining and interception and, thus, reduce the overall permeability. Transient flow behaviour is characterized by there parameters: a filter coefficient, a flow-redistribution parameter and a flow-restriction parameter. The filter coefficient controls the sharpness of the emulsion front, the flow-redistribution parameter dictates the steady-state retention, as well as the flow redistribution phenomenon, and the flow-restriction parameters describes the effectiveness of retained drops in reducing permeability.Critical comparison is made between the new filtration theory and the current continuum—viscous and retardation models for emulsion flow in porous media. Only the filtration picture is able to explain all the experimental observations. Quantitative comparison between the filtration flow theory and experiment is presented in Part II. 相似文献
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《Chemical engineering science》1986,41(5):1155-1161
This study of the radiation field generated in a cylindrical photoreactor irradiated from the bottom presents the theoretical foundations of a method for the experimental verification of three different radiation models. The expressions representing the local volumetric rate of energy absorption (LVREA) were formulated and applied to the prediction of the rate of an actinometric reaction. This reaction takes place inside a microreactor operated in a batch recycling system with polychromatic radiation.The values obtained portray the same behaviour as that of the energy densities calculated previously (Part I), thus becoming a valid, accurate method for the experimental measurement of the absolute values of the radiation field that are sought after (volumetric rate of energy absorption).The proposed approach is able to produce quasi-point values of the absolute values of the VREA at the microreactor as an excellent approximation to the absolute values of the LVREA (local measurements).The present work also points out the qualitative and quantitative discrepancies of the results predicted by the line models when compared with those of the extense source model with volumetric emission. 相似文献
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Zeolite-A was synthesized and converted into various ion-exchanged catalytic forms successfully. These catalysts were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Brunauer Emmett Teller (BET) surface area measurement and thermal programmed desorption (TPD). Their catalytic activity was tested on the synthesis of benzimidazole using o-phenylenediamine (OPDA) and aldehyde at room temperature. The reaction proceeds efficiently under ambient conditions. The catalysts gave a high isolated yield of benzimidazole in a shorter reaction time at room temperature and were recycled several times. 相似文献
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《Chemical engineering science》1986,41(2):273-281
Part I of this work outlined a new theory, based on deep-bed filtration concepts, to describe the flow of dilute, stable emulsions in underground porous media. Here, in Part II, we quantitatively test the proposed theory against experimental data and we indicate how the filtration model parameters can be estimated from first principles.Comparison is made between the theory and data on transient permeability and effluent concentration for dilute, oil-in-water emulsions of mean drop-size diameters ranging from 1 to 10 μm and volume concentrations of 0.5–2.5% flowing in quartz sandpacks of 0.57–2.0 μm2 permeability. The pH of the continuous aqueous phase is kept constant at 10. Filtration theory successfully represents the data, permitting unambiguous evaluation of the theoretical parameters.Procedures are described for a priori calculation of the filtration parameters from knowledge of the drop size and the pore-size and grain-size distributions of the porous medium. Good agreement is achieved between the experimentally determined parameters and their estimated values. Thus, the proposed filtration model provides a reliable tool for predicting emulsion flow behaviour in porous media. 相似文献
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In the present work, the production process of bio-jet paraffins is appropriately proposed according to the conditions of the socioeconomic situations, the current technologies of biofuel production and the available feedstock sources for the tropical countries. The blending process of bio-kerosene which is a mixture of bio-jet paraffins and fossil kerosene is also displayed. The two prototypes of bio-paraffins (Bio-P1 and Bio-JP2), which were manufactured in Indonesia following the proposed production process, are used for making bio-kerosenes in current study. The theoretical and experimental investigations have been carried out to evaluate and identify the critical properties of bio-kerosenes: distillations, freezing point, lower heating value, density, flash point and viscosity to ensure ASTM criteria of jet fuel. The results show it can be blended directly 5% volume of Bio-P1 or 10% volume of Bio-JP2 to commercial Jet A-1 for powering aviation gas turbine engines without redesigning fuel system or fuel supply infrastructure. The use of these bio-paraffins not only reduces CO2 lifecycle but also significantly decreases emissions of sulfur compounds (SOx). With preliminary achievements of this work, it is no doubt about the feasibility of developing aviation alternative fuels according to the proposed production process for the tropical countries. 相似文献