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Metal-organic frameworks (MOFs) are emerging materials with many current and potential applications due to their unique properties. One critical feature is that the physical and chemical properties of MOFs are tunable. One of the methods for tuning MOF properties is to introduce defects by design for desired applications. Characterization of MOF defects is important, but very challenging due to the local nature and short-range ordering. In this work, we have introduced the ordered vacancies (the defects) in the form of the coordinatively unsaturated sites (CUSs) into the framework of MOF MIL-120(Al). The creation of ordered vacancies is achieved by replacing one quarter of the BTEC (1,2,4,5-benzenetetracarboxylate) with BDC (benzene-1,4-dicarboxylate) linkers. Both parent and defective MOFs were characterized by multinuclear solid-state NMR spectroscopy. ¹H MAS NMR is used to characterize the hydrogen bonding in these MOFs, whereas ¹³C CP MAS NMR confirms unambiguously that the BDC is incorporated into the framework. One-dimensional ²⁷Al MAS NMR provides direct evidence of the coordinatively unsaturated Al sites (the defects). Furthermore, ²⁷Al 3QMAS experiments at 21.1 ​T allow direct identification of one penta-coordinated and three chemically inequivalent octahedral Al sites in the defective MIL-120(Al). Two of the above-mentioned octahedral Al sites are in the domain which appears defect-free. The third octahedral Al site is near the defective site. This work clearly demonstrates the power of solid-state NMR spectroscopy for characterization of defective MOFs.

A major challenge in upscaling and commercializing dye-sensitized solar cells (DSSC) is to simultaneously rely on a robust photoconversion efficiency (PCE) along with long-term device stability. Two-dimensional (2D) nanocarbon materials are known to improve the PCE and stability of devices made of hybrid nanocomposite photoanodes. However, there is inadequate knowledge on how the morphology of 2D nanocarbon materials plays an important role in improving photovoltaic (PV) performance and stability. Here we report the comparative effect on the PV performance and the long-term stability of DSSCs made of optimal loadings of few-layer graphene (FLG) flakes and graphene nanoribbons (GNR) into the mesoporous TiO₂ active layer. DSSCs were fabricated by using standard nanocrystalline TiO₂, GNR-TiO₂ and FLG-TiO₂ hybrid mesoporous films as anodes and subjected to continuous visible light irradiation to monitor their long-term stability. Results show that the optimized incorporation of GNR (0.005 wt%) and FLG (0.010 wt%) in the mesoporous TiO₂ active layer enhances the PCE by 34% and 21% compared to pristine TiO₂, respectively. Moreover, the operational stability of hybrid devices shows a 51.6% (for GNR-TiO₂) and a 10% (for FLG-TiO₂) sustained higher PCE than the device based on bare TiO₂, after 273 h of continuous one sunlight soaking. The electrochemical impedance spectroscopy (EIS) and transient photovoltage decay were studied to investigate how GNR strikingly reduces degradation of device performance as compared to its counterpart FLG-TiO₂ and TiO₂ based cells. This significant enhancement can be attributed to the structural modifications induced by GNR within the TiO₂ photoanode, which improves the electron lifetime and reduces non-radiative carrier recombination.

Background: Pain is a very important factor in patient recovery and satisfaction. Following incision and drainage of perianal abscess, wound packing has been found to be very painful. The aim of this study is to compare packing the wound and not packing the wound after incision and drainage (I&D) of perianal abscess, taking into account recurrence rate, rate of occurrence of perianal fistula as well as post-operative pain. Materials and Method: Standard medical electronic databases were searched with the help of a local librarian and relevant published randomised controlled trials (RCT) were shortlisted according to the inclusion criteria. The summated outcome of post-operative pain score, recurrence rate, and rate of occurrence of perianal fistula was evaluated using the principles of meta-analysis on RevMan 5 statistical software. Result: Three RCTs on 490 patients undergoing I&D of perianal abscess were found suitable for this meta-analysis. In the random effects model analysis, the post operative pain score was statistically lower in NPG [risk ratio 0.66, 95%, CI (0.36, 0.97), Z=4.25, P=0.0001]. There was no heterogeneity [Tau2=0.15; chi2=9.32; df=6; I2=36 %; p=0.16] between the studies, however, statistically it was not significant. In addition, there was no statistical difference between the 2 groups in terms of recurrence of perianal abscess or the occurrence of perianal fistula [risk ratio 0.64, 95%, CI (0.31, 1.31), Z=1.23, P=0.22], [risk ratio 1.41, 95%, CI (0.89, 2.23), Z=1.47, P=0.14] respectively. Conclusion: Not packing the wound post I&D of perianal abscess is associated with significantly reduced VAS pain scores, which may result in improved recovery and patient satisfaction and has no effect on recurrence rate or the occurrence of perianal fistula. However, more RCTs recruiting a greater number of patients are required to endorse these findings.

The best way for a person or an adult to gain knowledge, understanding, competence, and a positive outlook is through formal education. As a result, one undergoes maturation, honed skill, and instruction. The objective of the study is to find out the relationship between the quality of college life and students' academic motivation at the college level in the Multan division. The study used the descriptive method that used a correlational approach. The population of the study comprised all the women studies in the colleges that come under the jurisdiction of Multan division while the four hundred women were the sample of study who attended the college. The researchers used two questionnaires to collect data from the sample of the study. The study concluded that the quality of college life has a significant relationship with student's motivation. The study may recommend that college may foster a more upbeat environment for students' academic growth

Effective school leadership plays a crucial role in promoting a positive organizational culture and enhancing the quality of education in schools. This study aimed to evaluate the management skills and organizational culture of school heads in Southern Punjab. A quantitative research approach was used to gather information from the school head in Southern Punjab. A sample of 294 head teachers from southern Punjab was selected using a random sampling technique. The results showed that school heads in Southern Punjab have moderately high levels of management skills and moderately positive organizational cultures. There was a strong positive correlation between management skills and organizational culture, with management skills being a strong predictor of organizational culture. The findings highlight the importance of effective school leadership in promoting a positive organizational culture and enhancing the quality of education in schools.

MALL has grown in ESL classes during the previous decade. Researchers may now study the pros and cons of blended learning (BL), which combines online and in-person education. This quasi-experimental research examined how BL affects reading comprehension. This research examined how blended learning (BL) affected students' writing comprehension. 60 Pakistani secondary school pupils were split into control and experimental groups. The experimental group used "Reading Comprehension" mobile phone software to merge traditional teaching with blended learning for two months. An independent samples t-test compared pre-and post-test results. BL improved reading comprehension in the research.

The present study focuses on the use of politeness in teacher-student interaction in a Special Education institute in Pakistan. Using the concepts of Brown and Levinson (1987) and Leech (2014), visually impaired students in grade 8th were observed using or flouting politeness strategies and maxims in the classroom. The results show that the students used both positive and negative politeness strategies. The students repeatedly used negative politeness strategies in order to maintain social distance and to avoid imposition on the teacher. Also, they used maxims of modesty and obligation more frequently than the other maxims. Moreover, it has been observed that these students usually remained quiet and asked fewer questions during class. This research is significant in providing future researchers with a framework to work specifically in the domain of Special Education not only in Pakistan but also globally and will facilitate the development of pedagogical methods for inclusive education.

The Punjab Education Sector Reform Program (PSSP) was implemented in 2012 to improve the quality of education in public schools in Punjab, Pakistan. This study aims to compare the quality of teaching and management practices in public schools in Lodhran before and after the implementation of PSSP. The nature of the study was descriptive, while a survey was used to gather information from 250 PSSP school teachers out of 14 schools in Lodhran. The results showed significant improvements in the quality of teaching and management practices after implementing PSSP. Teachers reported feeling more supported and better equipped to teach, with increased access to professional development opportunities and teaching resources. School principals reported improved management practices, including better financial management, effective leadership, and accountability. The findings suggest that PSSP has positively impacted the quality of teaching and management practices in public schools in Lodhran.

Education plays a pivotal role to shape students personality for the benefit of society. The objective of the study was to find out the existing and achieved level of civic values. The population was undergraduate students studying social sciences at the University of Sargodha. The intact classes of BS 1st and 8th semesters were the sample of the study. The data were collected through a questionnaire regarding higher education and civic value. The data were analyzed by applying an independent sample t-test to compare the existing and achieved level of civic values of the students. The result revealed that the achieved level of civic values was more prominent than the existing level. It is recommended that such research should be conducted in different universities in Pakistan to find out the effect of the philanthropist role of students in building peace, cooperation and tolerance in society.

We report on triggering of p(NIPAM-AA) microgels’ photo-responsiveness by making complexes with a spiropyran (SP) containing surfactant. Being dissolved in water, the SP surfactant in its merocyanine state bears three charges, while irradiation with UV and vis light leads to the partial or complete reversal of the SP state. The complexation of the photo-responsive amphiphile with swollen anionic microgels results in charge compensation within the gel interior and as a consequence its size reduces and the volume phase transition temperature (VPTT) decreases down to 32 °C. Under irradiation the MC form photo-isomerizes to a ring closed SP state generating a more hydrophobic surfactant with one positive charge at the head. The increase in the hydrophobicity of the surfactant and thus of the interior of the gel results in the reversible size change of the microgel. We investigate the photo-responsivity of the microgel as a function of wavelength and irradiation intensity, as well as of surfactant concentration and charge density of the microgel. We show that the change in the size and VPTT of the microgels during irradiation occurs through a combination of two processes: heating of the solution during light absorption by the surfactant (more pronounced in the case of UV irradiation) and the change in the hydrophobicity of the surfactant.

Epoxy resins constitute a very significant portion of all high-performance plastics due to their excellent thermal and mechanical properties that appear in a wide range of applications. Nevertheless, traditional epoxy networks show limitations regarding chemical recycling due to their covalently crosslinked structures. The current methods to recycle epoxy resins are not indeed through sustainable ways, but this issue could be solved by developing smart monomers with functional groups, which can be switched between polymerized and depolymerized states. Herein, we developed two bio-based liquid monomers based on vanillin structures containing aldehyde, acetal, and oxirane-ring functionalities. These monomers were polymerized in solvent-free conditions using commercially available diamines, resulting in double-dynamic imine-acetal-containing thermosets. These networks combine the excellent properties of the traditional epoxy systems and dynamic polymers. Most importantly, such thermosets were fully depolymerized into vanillin, which can be reused for the preparation of original epoxy monomers, and a mixture of well-defined polyols, which was upcycled into high-performance polyurethane.

Resumen (Objetivo) En este trabajo se identifica y caracteriza el conocimiento especializado de tres profesores del área de matemáticas al analizar una secuencia de actividades, cuyo propósito es la enseñanza de la suma de fracciones empleando las Regletas de Cuisenaire. (Metodología) Se optó por un estudio cualitativo bajo un paradigma interpretativo, la intervención con los docentes se realizó durante cinco sesiones. Como instrumentos para la recolección de información se utilizaron entrevistas semiestructuradas, una secuencia de actividades y las Regletas de Cuisenaire en presentación digital. Para realizar la caracterización de los conocimientos se hizo uso del modelo del conocimiento especializado del profesor de matemáticas desarrollado por Carrillo y colaboradores. Tal modelo permite identificar el conocimiento que moviliza el docente de matemáticas en el campo de la enseñanza, así mismo permite organizarlo, clasificarlo y caracterizarlo. (Resultados) Desde los resultados de la investigación se obtuvo un mayor predominio en algunos de los subdominios que conforman el modelo, en particular, se encontró mayor influencia en el conocimiento de los temas y el conocimiento de las características del aprendizaje de las matemáticas. (Conclusiones) Finalmente, las reflexiones obtenidas en el estudio muestran la importancia de identificar los conocimientos que movilizan los docentes al momento de pensarse un proceso de instrucción, pues estos podrían ayudar a otros profesores a mejorar o reflexionar sobre sus prácticas de enseñanza y aprendizaje de las matemáticas, en este caso particular, el estudio de las fracciones. Abstract (Objective) This paper is intended to identify and characterize the specialized knowledge of three mathematics teachers through the analysis of a sequence of activities intended to teach the sum of fractions using Cuisenaire Rulers. (Methodology) A qualitative study using an interpretative paradigm was designed, and an intervention with the teachers was carried out during five sessions. Semi-structured interviews, a sequence of activities and Cuisenaire Rulers presented digitally were used as instruments for information collection. A model of specialized knowledge of the mathematics teacher developed by Carrillo and collaborators was used to characterize knowledge. This model makes it possible to identify the knowledge used by teachers in the field of mathematics, and to organize, classify and characterize it. (Results) The results of the investigation show a predominance of some of the subdomains that make up the model; in particular, a greater influence of knowledge of the topics and characteristics of learning mathematics. (Conclusions) Insights obtained during the investigation show the importance of identifying the knowledge that teachers make use of when thinking about an educational process, since this knowledge could help other teachers to improve or reflect on their teaching and learning practices in mathematics - in this particular case, in the study of fractions. Resumo (Objetivo) Neste artigo é identificado e caracterizado o conhecimento especializado de três professores de matemática por meio da análise de uma sequência de atividades, cujo objetivo é ensinar a soma de frações usando a Escala Cuisenaire. (Metodologia) Optou-se por um estudo qualitativo sob um paradigma interpretativo; a intervenção com os professores foi realizada durante cinco sessões. Como instrumentos de coleta de informações foram utilizadas entrevistas semiestruturadas, uma sequência de atividades e a Escala Cuisenaire em apresentação digital. Para caracterizar o conhecimento, foi utilizado o modelo de conhecimento especializado do professor de matemática desenvolvido por Carrillo e colaboradores. Tal modelo permite identificar o conhecimento que o professor de matemática mobiliza no campo da educação, assim como permite organizá-lo, classificá-lo e caracterizá-lo. (Resultados) Dos resultados da pesquisa, obteve-se uma maior predominância em alguns dos subdomínios que compõem o modelo, em particular, uma maior influência foi encontrada no conhecimento dos tópicos e no conhecimento das características da aprendizagem da matemática. (Conclusões) Finalmente, as reflexões obtidas no estudo mostram a importância de identificar os conhecimentos que os professores mobilizam ao pensar em um processo instrucional, pois podem ajudar outros professores a melhorar ou refletir sobre suas práticas de ensino e aprendizagem da matemática, neste caso particular, o estudo das frações.

Gravity separation of oil-water emulsions is an industrially crucial process. Mechanistic models for a batch separation process can immensely be beneficial by linking emulsion experimental characterization to optimal industrial equipment design. For this reason, a mathematical model for this process was developed, which considers droplets settling/ rising due to buoyancy force, binary and interfacial coalescence of the droplets using a film drainage model, and formation of a homophase. Various models for the droplet slip velocity were compared, which exhibit similar predictions using the Kumar and Hartland model and Behzadi et al. model while different from the Zaki and Richardson model. Another crucial part of the model is the proper mathematical description for forming the dense-packed layer (DPL). This study proposes a new approach to improve the prediction for the DPL formation by introducing diffusion in the model as an advection-diffusion equation. Accordingly, a suitable closure model for effective diffusion coefficient was selected, ensuring physical volume fraction range (0−1) in the system. Finally, the proposed closure model was tuned using experimental data for a stabilized water in model oil emulsion. Experiments were performed by the NMR technique for a wide range of initial water volume fractions (20–60%). The model prediction agrees well with the experiments. In particular, simultaneous agreement with all cases having various initial volume fractions and droplet size distributions suggests that this model can be generalized and applied to a wide range of oil and water emulsions. Additionally, the developed model shows promise as it can ensure physical values for volume fractions.

In this work, we propose a methodology to approach the design of chemical absorption columns with fast gas-liquid reactions by an experimental and modelling study, which accounts for thermodynamic (solubility) data, mass-transfer phenomena, and the reaction kinetics contribution. As a reference case, the SO2 absorption in aqueous solution of H2O2 at different concentrations, which oxidizes SO2 to sulfuric acid, is considered. A lab-scale fed-batch bubble column is used to evaluate SO2 solubility dataset in absorbing solutions of distilled water containing different dosages of H2O2. A thermodynamic model is developed and validated in a Thermodynamic Flash block of ASPEN PLUS®, allowing to describe the experimental results with optimum agreement. For kinetic experiments, a lab-scale falling-film absorber is used to investigate both SO2 mass-transfer rates and the fundamental kinetic aspects of an absorption process with chemical reaction. The physical contribution to the mass-transfer rate is evaluated through a set of dedicated experiments, which allowed determining gas-side (kGa) and liquid-side (kLa) coefficients in the falling-film absorber. Subsequently, the Enhancement factor (EL) of the SO2 oxidative absorption is evaluated for the oxidizing reaction (SO2 + H2O2 → H2SO4) under the explored experimental conditions, using the equilibrium dataset and the mass transfer coefficients previously obtained. Finally, EL is correlated to the Hatta number (Ha) with the Danckwerts kinetic model as a pseudo-mth-nth-order non-reversible reaction type and the model kinetic parameters are calculated.