Particulate Nature Research Articles

Green Synthesis of ZnMn2O4 Nanoparticles for Supercapacitor Applications

One of the important binary metal oxides, hetarolite (ZnMn2O4) was synthesized using the extract of Corallocarpus Epigaeus. The green synthesized nanoparticles have showed the tetragonal crystalline phase of ZnMn2O4 with the average crystalline size of 32 nm. The FT-IR study revealed the majorly presenting the Zn-O and Mn-O vibration peaks in the specimens. The band gap energy for the obtained nanoparticles through the Tauc’s plot method is 1.45 eV. The electron microscopic images revealed the particulate nature of the green synthesized ZnMn2O4 nanoparticles with an average particle size of 35 nm. Cyclic Voltammetry technique verified and validated the electrochemical properties of the prepared ZnMn2O4 nanoparticle. The examined electrochemical studies revealed the capacitance behavior as 380 F/g in aqueous electrolyte solution. The above studies has provided a splendid efficiency and proven that ZnMn2O4 can withstand as a prominent material for the super capacitor applications.

Effect of the Argumentation-Supported PBL on the Determination of PreService Science Teachers' Misconceptions about the Particulate, Space, and Motion Nature of Matter

Effect of the Argumentation-Supported PBL on the Determination of PreService Science Teachers' Misconceptions about the Particulate, Space, and Motion Nature of Matter

Fine tuning the structural colours of photonic nanosheet suspensions by polymer doping.

Aqueous suspensions of nanosheets are readily obtained by exfoliating low-dimensional mineral compounds like H3Sb3P2O14. The nanosheets self-organize, at low concentration, into a periodic stack of membranes, i.e. a lamellar liquid-crystalline phase. Due to the dilution, this stack has a large period of a few hundred nanometres, it behaves as a 1-dimensional photonic material and displays structural colours. We experimentally investigated the dependence of the period on the nanosheet concentration. We theoretically showed that it cannot be explained by the usual DLVO interaction between uniform lamellae but that the particulate nature of nanosheet-laden membranes must be considered. Moreover, we observed that adding small amounts of 100 kDa poly(ethylene oxide) (PEO) decreases the period and allows tuning the colour throughout the visible range. PEO adsorbs on the nanosheets, inducing a strong reduction of the nanosheet charge. This is probably due to the Lewis-base character of the EO units of PEO that become protonated at the low pH of the system, an interpretation supported by theoretical modeling. Oddly enough, adding small amounts of 1 MDa PEO has the opposite effect of increasing the period, suggesting the presence of an additional intermembrane repulsion not yet identified. From an applied perspective, our work shows how the colours of these 1-dimensional photonic materials can easily be tuned not only by varying the nanosheet concentration (which might entail a phase transition) but also by adding PEO. From a theoretical perspective, our approach represents a necessary step towards establishing the phase diagram of aqueous suspensions of charged nanosheets.

Challenges for Cell-Based Medicinal Products From aPharmaceutical Product Perspective.

Advanced therapy medicinal products (ATMPs), such as somatic cell-therapy medicinal products or tissue-engineered products for human use, offer new and potentially curative opportunities to treat yet untreatable diseases or disorders. For cell-therapy medicinal products (CBMPs), multiple stability and quality challenges exist and relate to the cellular composition and unstable nature of these parenteral preparations. It is the aim of this review to discuss open questions and problems associated with the development, manufacturing and testing of CBMPs from a pharmaceutical drug product perspective. This includes safety, storage and handling, particulates, the choice of container closure systems and integrity. Analytical methods commonly used to evaluate the quality of the final CBMP to ensure patient's safety will be discussed. Particulate contamination in final products deserve special attention since CBMPs cannot be sterile filtered. Visible and sub-visible particles may represent environmental contaminations or may form during storage. They may be introduced from processing materials such as single use product contact materials, ancillary materials, or any components such as primary packaging used for the final product. Currently available analytical methods for detecting particulates may not be easily applicable to CBMPs due to their inherent particulate nature and appearance.

Promoting senior primary school students’ understanding of particulate nature of matter through inquiry instruction with multiple representations

ABSTRACT This study examined the change in the two groups of senior primary school students’ understanding of particulate nature of matter (PNM) before and after each group involved in related instructions, namely inquiry instruction with multiple representations (IIMR) and regular instruction (RI). Data were collected through a two-tier questionnaire, and the data were analysed utilising statistical methods to compare the extent of change across the groups. The results revealed that both groups of students held similar but poor understandings of PNM before the instruction. Following the instruction, the IIMR students showed a greater improvement in scientific understandings about the PNM compared to their counterparts in the RI group. The results exhibited that carefully designed instruction of IIMR were strongly served for fostering students’ scientific understanding of PNM in comparison to the RI.

Fluidization Dynamics of Hydrophobic Nanosilica with Velocity Step Changes

Nanosilica is widely used in various applications, with its market expected to grow over USD 5 billion by 2025. The fluidized bed technology, owing to its intimate contact and efficient mixing of phases, is ideally suited for the large scale processing of powders. However, the bulk processing and dispersion of ultrafine nanosilica using the fluidized bed technology are critically affected by the interparticle forces, such that the hydrophilic nanosilica shows agglomerate bubbling fluidization (ABF), while the hydrophobic nanosilica undergoes agglomerate particulate fluidization (APF). This study carried out a detailed investigation into the fluidization hydrodynamic of the hydrophobic nanosilica by monitoring the region-wise dynamics of the fluidized bed subjected to a regular step change of fixed duration in the gas velocity. The gas flow was controlled using a mass controller operated with an analog output signal from a data acquisition system. The analog input data were acquired at the sampling rate of 100 Hz and analyzed in both time and temporal frequency domains. The effect of velocity transients on the bed dynamics was quickly mitigated and appeared as lower frequency events, especially in regions away from the distributor. Despite the apparent particulate nature of the fluidization, strong hysteresis was observed in both pressure drop and bed expansion. Moreover, the fully fluidized bed’s pressure drop was less than 75% of the theoretical value even though the bed appeared to free from non-homogeneities. Key fluidization parameters, e.g., minimum fluidization velocity (Umf) and the agglomerate size, were evaluated, which can be readily used in the large scale processing of nanosilica powders using fluidized bed technology.

Design of an electrostatic precipitator for a novel bituminous coal-fired circulating fluidised bed combustion power plant in Namibia

Coal-fired power plants utilising fluidised bed technologies emit copious amounts of fly-ash, which is harmful to people owing to its particulate nature. A planned 300 MW power plant will have an electrostatic precipitator (ESP) for fly-ash emissions control, in line with power generation industry best practices. This ESP should meet a fly-ash emission limit value ≤ 50 mg/Nm3. This paper details the design process and resultant technical specifications of a cold-side, single-stage, and plate-wire dry ESP designed for the power plant. The ESP will consist of twin-chambers with quadruple-fields (2 4 315 m3) and octonary bus-sections independently energised by individual high-frequency three-phase switched integrated rectifiers (70 kV, 800 mA) to maximise ionisation. Dynamically balanced, single-impact, tumbling hammer rappers (857.5 rpm) will dislodge fly-ash from the collector plates into mass-flow wedge-shaped hoppers. A specific collection area (≥ 56.9 m2/m3/s) and an ESP index (≥ 709.2 (kV/cm)2m2/m3/s) should guarantee a collection efficiency ( ≥ 99.5 %) and the specified emission limit value at 100 % boiler capacity and normal operating conditions (gas velocity ≤ 2.4 m/s; gas temperature ≤ 137 ℃; fly-ash loading ≤ 10 000 kg/Nm3; resistivity ≤ 1010 Ω‧cm). The design was successfully verified in principle using the validation square method, in conjunction with the leading comparable historical case studies approach. It is recommended to simulate ESP designs using suitable programs like Comsol Multiphysics and construct a pilot plant before attempting scaled-up construction and commissioning. Highlights A cold-side, single-stage plate-wire dry ESP system designed. Theoretical collection efficiency in excess of 99.5%. High-frequency, three-phase switched integrated rectifiers to be used for ionisation.

ENHANCING STUDENTS’ HIGH-ORDER COGNITIVE SKILLS FOR HIERARCHICAL DESIGNS IN MICRO AND SYMBOLIC PARTICULATE NATURE OF MATTER

To be familiar with micro and symbolic performances, students could work out more effective approaches of innovated techniques known as five hierarchical designs in chemistry equilibrium. However, the most frequently reported problem in students’ assessment of chemistry study is attributed to their poor skill recognizing basic concepts. The aim of this research was to construct the 6 test items to help undergraduate students assess their high-order and low-order cognitive skills as a deeper framework of particle representations. It takes a dynamic appeal for students to identify their profound understanding of cognitive skills in accordance with their potential performances of particle representations. In this research, students activate the test instrument to sustain their development of content validity and inter-rater reliability. The research results mark a different responsive engagement of both high-order and low-order cognitive skills in students’ total performances with the skill ratio score of 1:6 for conceptual recognition and analyses of micro and symbolic performances. All students’ micro and symbolic performances offer an indication for understanding their advanced cognitive skills in the particulate nature of matter. It is beneficial to improve new perspectives in the discussions and activity hierarchical designs in their chemistry equilibrium classrooms. Keywords: high-order cognitive skills, hierarchical designs, micro, symbolic performances, particulate nature of matter

Deflecting the Issue: The Origin of Nanoscale Material Build-up in Continuous Inkjet Printing

Continuous Inkjet (CIJ) printing relies on steering charged droplets accurately to the surface with electric fields. A vital component is the set of deflecting electrodes within the printhead that create these fields. Unwanted deposition of ink on the electrodes, known as build-up, is a concern for operators because it modifies the applied electric field, affects long-term reliability and requires manual intervention, but is not widely reported or explored. Here we report a laser-based high-speed visualisation technique to observe build-up and show it stems from small satellite droplets that break off from the main printed drops. We characterise the material build-up and reveal its nanoscale particulate nature. Combining the tracking with characterisation allows us to quantify the charge-to-mass ratio of these droplets. This study provides a route to understand the build-up phenomenon and will enable optimisation of the printing conditions and printing reliability.

Development and Application of the Multiple Representation-Based Learning Strategies Using Augmented Reality on the Concept of the Particulate Nature of Matter

Development and Application of the Multiple Representation-Based Learning Strategies Using Augmented Reality on the Concept of the Particulate Nature of Matter

Deflecting the Issue: The Origin of Nanoscale Material Build-up in Continuous Inkjet Printing

Abstract Continuous inkjet printing relies on steering charged droplets accurately to the surface by using electric fields. A vital component is the set of deflecting electrodes within the printhead, which create these fields. Unwanted deposition of ink on the electrodes, known as build-up, is a concern for operators because this modifies the applied electric field, affects long-term reliability, and requires manual intervention. However, this has not been widely reported or explored. Here, the authors report a laser-based high-speed visualization technique to observe build-up and show that it stems from small satellite droplets that break off from the main printed drops. They characterize the material build-up and reveal its nanoscale particulate nature. Combining the tracking with characterization allows quantifying the charge-to-mass ratio of these droplets. This study provides a route to understanding the build-up phenomenon, and it will enable optimization of printing conditions and printing reliability.

68. Spinal fusion with a resorbable mesh pouch in a preclinical posterolateral model

BACKGROUND CONTEXT Delivery and handling of graft material during surgery can be challenging often due to the particulate nature of materials, irrigation and risk of migration. Resorbable mesh pouches (RMP) offer a simple and effective way to handle and implant particulate grafts, maintain host bone contact and avoid migration. The current RMP was composed of a PLGA mesh. Two studies were performed using a well reported single level posterolateral rabbit spinal fusion model. Study 1 evaluated the RMP prefilled with demineralized bone matrix (DBM) and used as an extender with autograft while Study 2 evaluated the RMP filled with corticocancellous iliac crest autograft. An Autograft alone group was used as a positive control group in each study. PURPOSE To confirm that a porous resorbable mesh pouch, used to facilitate placement and containment of graft material does not impede bone formation. STUDY DESIGN/SETTING Preclinical in vivo study. PATIENT SAMPLE Not applicable. OUTCOME MEASURES Not applicable. METHODS Eighty skeletally mature female New Zealand White rabbits were enrolled following ethical approval in two studies. The transverse processes were exposed and decorticated with a pneumatic high-speed burr. The implant groups were 2cc of autograft, 2cc of autograft inside the RMP, or RMP pre-filled with 2cc DBM placed on top of 1cc of autograft bilaterally in the posterolateral gutters. Fusion assessment at 3 days (n=2 per group), 4 and 8 weeks (n=5 per group) and 12 weeks (n=8 per group) included manual palpation, X-rays, Faxitron radiographs, micro CT, histology and histomorphometry for bone formation as well as polymer resorption and reaction using polarized light. Statistical analyses were performed using a non-parametric Kruskal Wallis test for manual palpation, radiographs and micro CT grading while an ANOVA was used for histomorphometry and non-destructive range of motion testing. RESULTS All animals recovered uneventfully following surgery. No adverse reactions were noted macroscopically. The positive control groups performed consistently with the model and literature. Manual palpation at 12 weeks for RMP groups was 6/8 in both studies. Radiograph and micro computed tomographic grading and pmMA histomorphometry did not detect any differences between the groups at any time point. Paraffin histology revealed no adverse reactions associated with the RMP. The RMP pre-filled with DBM and combined with autograft or filled with autograft alone remodeled in the same manner as the positive control. The RMP progressively resorbed with time and was nearly completely resorbed by 8 weeks with no adverse cellular or tissue reactions. CONCLUSIONS The RMP facilitated graft placement and handling and did not impede the biology of healing and remodeling of autograft in the single-level rabbit spine model. FDA DEVICE/DRUG STATUS Resorbable Mesh Bag (Ballast) (Approved for this indication)

The drama of chemistry – supporting student explorations of electronegativity and chemical bonding through creative drama in upper secondary school

ABSTRACT Getting students to understand the particulate nature of matter is a major challenge for chemistry education. In upper secondary school students commonly struggle to distinguish between intra- and intermolecular bonding and analyse chemical bonding in terms of electronegativity. In this study, we explore how creative drama may be used in chemistry education to facilitate students’ explorations of electronegativity and chemical bonding in Swedish upper secondary chemistry education. The study was conducted as a design-based intervention in three cycles in two schools. The interventions (which lasted for 30–60 minutes) were single-lesson-interventions consisting of drama activities and discussions in whole-class and student groups. A qualitative content analysis produced themes that captured the ways in which the students explored electronegativity and chemical bonding and how creative drama enabled collective student agency. The findings indicate that creative drama enabled the students to link the electronegativity and polarity of molecules to formations of molecular grid structures using their own bodies to represent how molecules were organised in different states of matter. The results also indicate that creative drama in chemistry education may enhance student agency in their explorations of electronegativity and the linking of electronegativity to intramolecular and intermolecular bonding.

Hannah Arendt: Socratic Citizenship and Philosophical Critique

Abstract In this essay I trace the relationship between philosophy and politics in Hannah Arendt’s work, with specific reference to the tension between her Socratic commitments and her appeal to “common sense” or sensus communis. I argue Arendt’s idea of a “common sense of the world” gives rise to a conception of the public realm that has too much shape and integrity to fit the often misty and particulate nature of contemporary reality. This is not the familiar critique of Arendt as a nostalgic Grecophile. Rather, it is a critique aimed at the phenomenological concept of “world” underlying her analysis. This concept—derived, but notably different, from Husserl’s and Heidegger’s respective conceptions—relies on background practices and understandings that are thick enough to sustain both a common public culture and a shared “sense of the world.” I suggest that Arendt’s appeal to a sensus communis runs aground of the moral and value pluralism that both Weber and Berlin have suggested are constitutive features of modernity. I conclude with some remarks on the relationship between Arendt’s critique of modernity and Socratic philosophical critique (on the one hand) and Frankfurt School Critical Theory (on the other).

Rotavirus Inner Capsid VP6 Acts as an Adjuvant in Formulations with Particulate Antigens Only.

Novel adjuvants present a concern for adverse effects, generating a need for alternatives. Rotavirus inner capsid VP6 protein could be considered a potential candidate, due to its ability to self-assemble into highly immunogenic nanospheres and nanotubes. These nanostructures exhibit immunostimulatory properties, which resemble those of traditional adjuvants, promoting the uptake and immunogenicity of the co-administered antigens. We have previously elucidated an adjuvant effect of VP6 on co-delivered norovirus and coxsackievirus B1 virus-like particles, increasing humoral and cellular responses and sparing the dose of co-delivered antigens. This study explored an immunostimulatory effect of VP6 nanospheres on smaller antigens, P particles formed by protruding domain of a norovirus capsid protein and a short peptide, extracellular matrix protein (M2e) of influenza A virus. VP6 exhibited a notable improving impact on immune responses induced by P particles in immunized mice, including systemic and mucosal antibody and T cell responses. The adjuvant effect of VP6 nanospheres was comparable to the effect of alum, except for induction of superior mucosal and T cell responses when P particles were co-administered with VP6. However, unlike alum, VP6 did not influence M2e-specific immune responses, suggesting that the adjuvant effect of VP6 is dependent on the particulate nature of the co-administered antigen.

A phase field model for cohesive fracture in micropolar continua

While crack nucleation and propagation in the brittle or quasi-brittle regime can be predicted via variational or material-force-based phase field fracture models, these models often assume that the underlying elastic response of the material is not size-dependent. Yet, a length scale parameter must be introduced to these models to enable sharp cracks properly represented by a regularized implicit function. However, many materials with internal microstructures that contain surface tension, micro-cracks, micro-fracture, inclusion, cavity or those of particulate nature often exhibit size-dependent behaviors in both the path-independent and path-dependent regimes. This paper is intended to introduce a unified treatment that captures the size effect of the materials in both elastic and damaged states. By introducing a cohesive micropolar phase field fracture theory, along with the computational model and validation exercises, we explore the interacting size-dependent elastic deformation and fracture mechanisms exhibits in materials of complex microstructures. To achieve this goal, we introduce the distinctive degradation functions of the force-stress–strain and couple-stress-micro-rotation energy-conjugated pairs for a given regularization profile such that the macroscopic size-dependent responses of the micropolar continua are insensitive to the length scale parameter of the regularized interface. Then, we apply the variational principle to derive governing equations from the micropolar stored energy and dissipative functionals. Numerical examples are introduced to demonstrate the proper way to identify material parameters and the capacity of the new formulation to simulate complex crack patterns in the quasi-static regime.

3D Hierarchically Mesoporous Zinc-Nickel-Cobalt Ternary Oxide (Zn0.6Ni0.8Co1.6O4) Nanowires for High-Performance Asymmetric Supercapacitors.

Increased efforts have been devoted recently to develop high-energy-density supercapacitors (SC) without renouncing their power efficiency. Herein, a hierarchically mesoporous nanostructure of zinc-nickel-cobalt oxide (ZNCO) nanowires (NWs) is constructed by hierarchical aggregation of ZNCO nanoparticles. It is worth noting that cobalt and nickel rich lattice imparts higher charge storage capability by enhanced reversible Faradaic reaction while zinc provides structural stability and higher conductivity. Moreover, particulate nature of ZNCO NWs allows deep diffusion of electrolyte thus enabling reversible charge storage under higher current densities. The as-prepared ZNCO NWs exhibited excellent specific capacitance of 2082.21 F g−1 at the current density of 1 A g−1 with high stability up to 5,000 charge-discharge cycles. Further, the asymmetric SC device was assembled using ZNCO NWs (ZNCO NWs//MWCNTs) which exhibited high energy density of 37.89 Wh kg−1 and excellent capacitance retention up to 88.5% over 1,000 cycles. This work presents ways to construct multi-component high-energy-density materials for next-generation energy storage devices.

The Use of Information and Communication Tools to Teach Particulate Nature of Matter: A Study of a Science Class

This paper deals with the use of information and communication tools to teach particulate nature of matter in a Science class at Guakro Effah Senior High School in the Techiman North District of Ghana. The research design used for the study was action research. A sample of 35 students were selected for the study using convenience sampling technique. The instrument used for gathering data were test and observation. Information and communication tools were used to teach the students during the intervention. Data collected was analysed with descriptive and inferential statistics. The findings revealed that students understand abstract concepts better when information and communication tools were used to teach, students’ performance improved and they were motivated during Chemistry lesson when information and communication tools were used to teach. The study recommends the need to use information and communication tools to teach abstract concepts in chemistry and the need to priorities in-service training and seminars for Science teachers to improve on their skills in order to use information and communication tools in delivery of their lessons effectively. Keywords: Information, Communication tools, Particulate Nature of Matter DOI: 10.7176/JEP/11-13-11 Publication date: May 31 st 2020

Ultraefficient stabilization of high internal phase emulsions by globular proteins in the presence of polyols: Importance of a core-shell nanostructure

We report that oil-in-water (o/w) high internal phase emulsions (HIPEs) can be ultra-efficiently stabilized by globular proteins in the presence of appropriate concentrations of polyols. Using bovine serum albumin (BSA) and trehalose as the model globular protein and polyol, stable HIPE gels at 0.8 oil volume fraction can be easily prepared at a protein concentration in the aqueous phase as low as 0.005 wt% in the presence of 40 wt% trehalose. Higher concentrations of polyols facilitated the formation of finer HIPEs with a stronger gel network associated with a higher extent of droplet bridging. The HIPE gels exhibited excellent coalescence stability against long-term storage or upon extensive heating. The ultra-efficient stabilization of BSA in the presence of trehalose arises from two contributions: facilitated formation of bridged emulsions and interfacial stabilization of trehalose aggregates. The soft particulate nature of BSA in the presence of trehalose was due to the formation of a core-shell nanostructure with trehalose molecules surrounding the protein core. The findings provide a novel and facile strategy to transform globular proteins into outstanding soft particles for stabilizing HIPEs, as well as guiding the development of novel biocompatible and even food-grade HIPEs with promising applications in the food, cosmetics and pharmaceutical fields.

Learning in embodied activity framework: a sociocultural framework for embodied cognition

This paper proposes the Learning in Embodied Activity Framework (LEAF) which aims to synthesize across individual and sociocultural theories of learning to provide a more robust account of how the body plays a role in collaborative learning, particularly when students are learning about a collective phenomenon where coordination between and across students is important to their learning. To demonstrate the uses and limits of LEAF, we apply it to data from several iterations of the Science through Technology Enhanced Play (STEP) project. This project involved first and second-grade students using an embodied, mixed-reality simulation to learn about the particulate nature of matter. We use data from this project to demonstrate the ways in which students’ embodied actions serve as a resource in understanding their embodied activity both individually and collectively. We demonstrate how both dimensions provide insight into student cognition and learning. Supported by this analysis, we present LEAF as a useful tool to help researchers, designers, and instructors thoughtfully design collective activities.