A Three-Dimensional Population Balance model of Granulation Processes Employing Mechanistic Kernels

Granulation is a process for agglomeration where powder material is combined with liquid binder solution to facilitate the formation of larger, free-flowing granules. Granulation has become a mainstream process amongst the industries with applicability in numerous areas, which include the pharmaceuticals, mineral processing, fertilisers and in the production of a range of commodity products. A major driVing force for the production of granules from their ungranulated counterparts arises from the economic savings Le., increased bulk density permits savings to be made in transportation. and storage. Furthermore, granules may be tailored to possess certain desirable attributes that will suit the final application of the granules. Granulation is an example of a process that exhibits complex interactions between the underlying granulation phenomena such as nucleation, consolidation, aggregation and breakage. In addition, the granUle properties are distributed heterogeneously across the entire particle population posing as a particular challenge in generating a mathematical model that is able to accurately describe the granulation behaviour. The modelling approach used in this study is different from common practices, which tend to rely on heuristics and empiricism for the operation of the granulation process. This empirical approach signifies a disconnect from our understanding of the underlying physics of the process, which poses as a impediment towards the efficient operation of granulation processes. The work presented in this thesis attempts to address this disconnect by applying a threedimensional population balance with mechanistic representations for the underlying granulation rate processes. The population balance framework is ideally suited for this particular process, as it enables the evolution of the granules to be tracked with respect to differentiating particle traits, e.g. the granule size distribution. The selection of the desired properties is influenced by the importance of these particle properties on the end granule product, and also by their influence on key process mechanisms. A novel mechanistic nucleation kernel is developed incorporating fundamental material properties pertaining to the powder substrate and the liquid binder solution. The model form of the nucleation kernel is formulated by drawing a parallel with the collision/transition state theory. There are few literature reports on the inclusion of nucleation phenomena in the population balance models of granulation processes, let alone a mechanistic nucleation model. This study is one of the first in this regard. The recent recognition of the importance of the wetting kinetics and the nucleation thermodynamics on the nucleation phenomenon has been factored into the nucleation kernel by explicitly accounting for the effects of the liquid flow rate and the physicochemical properties of the material properties (surface tension, contact angle, and spreading coefficient). Batch granulation experiments were conducted obtaining granule measurements with respect to the size distribution, porosity and fractional binder content. Preliminary results for the validation of the population balance model with the experiment-measurements showed a good agreement, providing partial albeit valuable validation of the population balance model. This is also one of the first studies to model and validate a three-dimensional population balance model for granulation. Model based analyses were also carried out under a variety of processing conditions, which included the effects of changing formulations, droplet size effects, feed size distribution and the effects of powder and binder properties. The proposed model demonstrated the interactions for a range of feed formulations in tandem with granulating operating conditions, establishing qualitative agreement with similar findings derived from past experimental studies.Imperial Users onl

Protein crystallization in vivo

Protein crystallization in vivo provides some fascinating examples of biological self-assembly. Here, we provide a selective survey to show the diversity of functions for which protein crystals are used, and the physical properties of the crystals thatare exploited. Where known, we emphasize how the nature of the protein-protein interactions leads to control of the crystallization behaviour.Comment: 17 pages, 1 figur

Dual Enrollment, First-Year Retention, and Graduation: Analyzing the Impact of Dual Enrollment on Student Success Outcomes at a Public Research University

As more higher education institutions participate in offering college-level courses to high school students (often referred to as dual enrollment) it becomes increasingly important to evaluate the impact of participation in these courses on subsequent higher education student success outcomes, such as first-year retention and graduation rates. In recent years, there has been an increase in the body of literature devoted to this topic, however, much of this literature is aimed at analyzing the impact of dual enrollment courses on performance in community colleges. This study will examine the relationship between high school students taking dual enrollment courses and their later performance at a public, R1 university. Additionally, this study will employ Classification and Regression Trees (CART), a type of supervised statistical learning for identifying the success factors for dually enrolled students based on academic, demographic, and socioeconomic features. This study intends to offer results that provide generalizable knowledge for institutional decision-making pertaining to dual enrollment and success in higher education

Efficient Algorithm for Generating Order Packing Recommendations

Packing an order in the most appropriately sized boxes can improve customer experience, reduce costs, and alleviate stress for the operator that packs the items into the boxes. Products to determine optimal packaging typically consider permutations of packing options and select one that likely minimizes total costs while preventing the likelihood of product damage. However, such products use algorithms where the runtime increases exponentially with the addition of a box or an item in the input, thus making them impractical for orders that require multiple boxes and items. Moreover, such products typically do not take merchant and product variations and specialized needs into consideration. This disclosure describes an efficient general-purpose algorithm to generate packing recommendations. The algorithm produces near-optimal packing recommendations within a reasonable time

Evaluating User Satisfaction and Organisational Benefits of Electronic Medication Management System in an Australian Hospital

In this conceptual paper, we speculate on the possibility that a PhD by Artefact and Exegesis (A&E) may be legitimate in the Information Systems (IS) discipline. Research, as creative process and product with the intention of yielding new knowledge, takes many forms across the spectrum of academic disciplines. Other disciplines, particularly in the humanities’ fields of arts and design, have artefacts as a discrete part of their PhD product accompanied by an exegesis of one form or another. It may be that some research in the IS discipline lends itself to the A&E approach. This paper considers A&E PhDs in Humanities and how practice-based research is presented. We explore how A&E might apply to IS research, through comparison with the design science approach. We suggest tentative impacts on candidates, supervisors and examiners then conclude with the issues and open questions raised by our investigations

KINEMATIC DIFFERENCES BETWEEN ‘ONE-FOOTED’ AND ‘TWO-FOOTED’ YOUNG SOCCER PLAYERS KICKING WITH THE NON-PREFERRED LEG

The purpose of this study was to examine kinematic differences between ‘one-footed’ and ‘two-footed’ players when kicking with the non-preferred leg at a target and with maximal effort. Eighteen highly-trained young soccer players were categorised as one-footed (n=9) and two-footed (n=9) based on results of a kicking test. Motion analysis data showed that two-footed players run-up straighter and have less pelvic rotation at ball-foot impact than one-footed players and the differences are likely to be meaningful (ES differences of 0.89 and 0.99 respectively). Run-up angle and pelvic rotation angle are significantly correlated (P < 0.1). The study found that two-footed players are significantly smaller in stature than one-footed players (P < 0.1). Practical implications for soccer coaches arose from the study