172 research outputs found
Woodside Energy Ltd. Cossack Pioneer Facility Engineering Team
No full textCossack Pioneer is a floating production storage and offloading vessel located 112 km North West of Karratha. This report details the work performed during a 16 week internship with Woodside Energy Ltd working in the Cossack Pioneer Facility Engineering Team. This Perth based team provides engineering support to the production facility. The report incorporates a description of the facility and topsides process and discusses the systems used for process control.
The earlier work performed during the internship focussed on small engineering design and control system modifications for the instrumentation and control group within the facility engineering team. Partway through the internship focus changed and the challenging role of Facility Control Engineer for Cossack Pioneer was assumed during the absence of the facility Senior Control Engineer. The report provides discussion of learning outcomes acheived and experience gained during the internship
Corrigendum to Developing a Sustainability Indicator Set for Measuring Green Infrastructure Performance
No full textThere was only one correction in corresponding author. It should be Parisa Pakzad
Living alpha-olefin polymerization by cationic zirconium and hafnium complexes containing chelating diamidopyridine ligands
No full textThesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Chemistry, 2002.Vita.Includes bibliographical references (leaves 196-199).This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.by Parisa Mehrkhodavandi.Ph.D
Volumetric additive manufacturing of glass
No full textreservedAbstract
Volumetric additive manufacturing (VAM) is a new and highly efficient method for creating complex glass structures with great precision. This study looks at a technique called xolography, a type of volumetric 3D printing that uses colloidal silica suspensions to make glass parts. Unlike traditional additive manufacturing that builds parts layer by layer, xolography can solidify entire volumes at once and this efficiency allows for the quick production of detailed and defect-free glass components with high resolution.
The main goal of this research is to create a new and effective method for making high-purity glass using xolography. This study focuses on the rheological and optical properties of photopolymerizable resin, evolution of chemical structures and phases during heat treatment, as well as fine-tuning printing settings to ensure strength, transparency, and durability. It also examines how different sintering conditions affect the densification and optical properties of the printed glass.
Stable photopolymerizable resin with colloidal silica inks was formulated with controlled viscosity and light absorption to facilitate photopolymerization. Resin composition and printing parameters, such as UV light intensity and printing speed, were optimized. To achieve dense and crack-free glass, we studied thermal processes including debinding and sintering. Scanning Electron Microscopy (SEM) for microstructure analysis, Fourier Transform Infrared Spectroscopy (FTIR) for examining chemical bonds, and X-ray Diffraction (XRD) for phase evolution assessment were performed.
Experimental results demonstrate that xolography enables the production of highly complex and transparent glass structures with high fidelity and excellent optical clarity, highlighting the potential of volumetric additive manufacturing in glass fabrication by significantly reducing processing time and material waste while maintaining superior structural and optical properties.
Crack-free glass samples were obtained by carefully optimizing the debinding procedure. This study provides a clear framework for using xolography to create complex shapes, and marks an advancement in the volumetric additive manufacturing of glass. Further improvements in developing higher transparency feedstocks, achieving higher resolution, and managing multi-material printing will be useful.
Keywords: VAM, Volumetric Additive Manufacturing, High-Resolution 3D Printing, Xolography, Advanced Glass Manufacturing, Transparency, Photopolymerization, Amorphous materials.Abstract
Volumetric additive manufacturing (VAM) is a new and highly efficient method for creating complex glass structures with great precision. This study looks at a technique called xolography, a type of volumetric 3D printing that uses colloidal silica suspensions to make glass parts. Unlike traditional additive manufacturing that builds parts layer by layer, xolography can solidify entire volumes at once and this efficiency allows for the quick production of detailed and defect-free glass components with high resolution.
The main goal of this research is to create a new and effective method for making high-purity glass using xolography. This study focuses on the rheological and optical properties of photopolymerizable resin, evolution of chemical structures and phases during heat treatment, as well as fine-tuning printing settings to ensure strength, transparency, and durability. It also examines how different sintering conditions affect the densification and optical properties of the printed glass.
Stable photopolymerizable resin with colloidal silica inks was formulated with controlled viscosity and light absorption to facilitate photopolymerization. Resin composition and printing parameters, such as UV light intensity and printing speed, were optimized. To achieve dense and crack-free glass, we studied thermal processes including debinding and sintering. Scanning Electron Microscopy (SEM) for microstructure analysis, Fourier Transform Infrared Spectroscopy (FTIR) for examining chemical bonds, and X-ray Diffraction (XRD) for phase evolution assessment were performed.
Experimental results demonstrate that xolography enables the production of highly complex and transparent glass structures with high fidelity and excellent optical clarity, highlighting the potential of volumetric additive manufacturing in glass fabrication by significantly reducing processing time and material waste while maintaining superior structural and optical properties.
Crack-free glass samples were obtained by carefully optimizing the debinding procedure. This study provides a clear framework for using xolography to create complex shapes, and marks an advancement in the volumetric additive manufacturing of glass. Further improvements in developing higher transparency feedstocks, achieving higher resolution, and managing multi-material printing will be useful.
Keywords: VAM, Volumetric Additive Manufacturing, High-Resolution 3D Printing, Xolography, Advanced Glass Manufacturing, Transparency, Photopolymerization, Amorphous materials
Determining Area Affected by Corona in Lung Computed Tomography Images by Three-phase Level Set and Shearlet Transform
No full textAbstract Background: The COVID-19 pandemic has created a critical global situation, causing widespread challenges and numerous fatalities due to severe respiratory complications. Since lung involvement is a key factor in COVID-19 diagnosis and treatment, accurate identification of infected regions in lung images is essential. Methods: We propose a multiphase segmentation method based on the level set framework to determine lunginvolved areas. The shearlet transform, a high-precision directional multiresolution transform, is employed to guide the gradient flow in the level set formulation. Additionally, the phase stretch transform (PST) is applied to enhance the contrast between infected and healthy regions, improving convergence speed during segmentation. Results: The proposed algorithm was tested on 500 lung images. The method accurately identified infected areas, enabling precise calculation of the percentage of lung involvement. The use of the shearlet transform also allowed clear delineation of ground-glass opacity boundaries. Conclusion: The proposed multiphase level set method, enhanced with shearlet and phase stretch transforms, effectively segments COVID-19–infected lung regions. This approach improves segmentation accuracy and computational efficiency, offering a reliable tool for quantitative lung involvement assessment
Isolating, characterizing, and engineering novel Cu-proteins and peroxidases
No full textMetalloproteins are a fascinating class of proteins that function at the heart of several important biological processes including photosynthesis, respiration, and nitrogen fixation. It is even more amazing, considering that nature uses a small set of tertiary structures and metal centers to perform all these different functions with efficiency and selectivity. How nature tunes the activity within these scaffolds has been the area of research for many years. The goal of this work is to understand the underlying mechanisms of such tuning with a special focus on the role of subtle changes of residues in the secondary coordination sphere of the metal ion, an underexplored area of study. I use protein engineering techniques not only to shed light on the mechanisms underlying such changes, but also to design new functionalities within our scaffold proteins and to enhance their properties for specific purposes, such as fuel generation.
This work is divided into three main sections. In the first, I focus on characterizing a novel metalloprotein, N. mar_1307, from the organism Nitrosopumilus maritimus. While the protein shares a protein fold and Type 1 copper coordination site with other common electron transfer cupredoxins, the lack of an axial residue creates an open binding position in the Cu center, leading to a novel enzymatic function, NO oxidation. The purification, characterization, and activity assays of the protein are described in detail in chapter 2.
The second and major focus of this work is on tuning the reduction potential of azurin, a common electron transfer protein. In chapter 3 I demonstrate that how by making mutations around the Cu site, and replacing Cu with Ni I can obtain an azurin variant with a reduction potential of nearly 1V, the highest potential that can be observed under physiological conditions, along with other variants with negative potentials. Chapter 4 describes the characterization of a series of Phe114 mutants that were used to understand the role of this critical secondary sphere residue in tuning the reduction potential of the Cu site. Chapter 5 demonstrates the Marcus inverted region of electron transfer in a series of azurin variants with different reduction potentials. Finally, I show my initial attempts toward the design of a high-throughput screening platform for the directed evolution of azurin in chapter 6.
In chapters 7 and 8, I focus on the design of novel functionalities in one of our model scaffolds, cytochrome c peroxidase (CcP). Chapter 7 describes the work done to enhance the Mn(II) oxidation activity in a designed model of manganese peroxidase within the CcP scaffold based on modifications of the second coordination sphere around the Mn(II) binding site. In chapter 8 I report the design and characterization of a novel CcP variant that shows catalase-like activity in “as-purified” form and forms a heme-protein crosslink in the heme-bound form.Submission published under a 24 month embargo labeled 'Closed Access', the embargo will last until 2017-12-01The student, Parisa Hosseinzadeh, accepted the attached license on 2015-09-17 at 11:09.The student, Parisa Hosseinzadeh, submitted this Dissertation for approval on 2015-09-17 at 11:57.This Dissertation was approved for publication on 2015-10-08 at 14:46.DSpace SAF Submission Ingestion Package generated from Vireo submission #8686 on 2016-03-02 at 14:11:52Made available in DSpace on 2016-03-02T20:57:17Z (GMT). No. of bitstreams: 2
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Correction: Recent Advances in Atmospheric Chemistry of Mercury
No full textThe published paper [1] has been updated to remove instances of copied text from otherpublications [2–6]. Changes have been made throughout the paper, with the most significant alterationsmade in Sections 2.1, 2.4, 3.1, 3.2, 3.3, and 4.The authors wish to provide the following explanation. Ref. [1] is a review article that was invitedfor the journal Atmosphere. The author Lin Si took the lead in writing the article, although this is thefirst time she has undertaken writing a review paper. Sections copied were cited, and a number ofthem were taken from Parisa A. Ariya’s previously published articles. The authors offered to retractthe paper. As scientists we are seeker of the truth, and our integrity and ethics are the most preciousgifts that we leave to future next generations.This Correction was deemed necessary to avoid the impression that the text presented in [1]was the original work of the authors. The Editorial Office accepts that the authors did not intend tomisrepresent the work, however, the original wording did not make it sufficiently clear that a numberof passages were direct quotations.We wish to thank the authors for their cooperation and apologize to readers that this case was notdetected earlier. Atmosphere routinely checks submitted manuscripts for duplication, but issues weremissed in this case due to human error
The politics of the night: feminine writing and mother-daughter relations in Djuna Barnes, Angela Carter, and Shahrnush Parsipur
No full text© 2018 Dr Parisa ShiranThis thesis uses Luce Irigaray’s philosophy of sexual difference and Maurice Blanchot’s orphic philosophy of literature to examine representations of night in the fiction of three women novelists, Djuna Barnes, Angela Carter and Shahrnush Parsipur. Performing a feminist psychoanalytical reading of Blanchot, I reveal the various ways in which his poststructuralist literary theory rests upon and reflects the phallocentric constitution of the symbolic whereby linguistic signification (the production of the literary work) depends upon the loss of the mother (Eurydice), and the nocturnal exteriority of maternal-female sexual difference. If literature is the impossible movement towards the darkness of maternal origin (the other night), then it is twice as impossible for the female author to move towards the prelinguistic night of maternal origin because of the incest taboo and the phallocentric relegation of maternal-female sexuality to the unconscious. Through a combination of feminist psychoanalysis and literary criticism, the thesis proposes that a feminine literary category marked by maternal-female sexuality is a near-impossibility. However, I go beyond a feminist appropriation of Blanchot’s concept of the other night in order to explain the political relevance of the author’s sex in writing. The thesis also has a comparative dimension because the night is a key concept in Persian literature and in Sufism. In so far as Parsipur’s imagery of the pre-Oedipal night takes on a mystical shape very different from that of Barnes and Carter, the thesis reveals the cultural formation of the unconscious across different socio-cultural geographies in world literature
The catalyst role of school architecture in enhancing children's environmental behavior
No full textThe interrelationships between school design and children learning are well established. Less evident is
the relationship between sustainable school design and the level of environmental behaviour of the
children in attendance. Newly erected primary schools in Australia have been broadly graded as either sustainable or conventional. This paper evaluates the impact of both sustainable and conventional school design on children’s environmental behaviour, and examines the correlation between school design and children’s environmental behaviour. 624 children, aged 10-12 years old, completed a survey. This sample, from seven selected primary schools in Victoria (Australia), includes four conventional schools and three sustainable ones. The survey was developed according to GEB (General Ecological Behavior) scale and a few more school specific variables. The outcome of the survey was analyzed using an independent sample t-test and two-way between groups ANOVA in order to assess environmental behavior differences of children in both sustainable and conventional schools taking into account factors that either explicitly and/or implicitly impact on
their behavior such as sustainable school design, teachers’ environmental behavior and parents’
environmental behavior. The results show statistically significant differences in environmental behavior of children in sustainable schools and those in conventional schools. Comparing the means of children’s environmental behavior indicates that children in sustainable schools posses higher levels of pro-environmental behavior than children in conventional schools. The paper highlights the strong relationships between school design and children’s environmental behavior, and expands recognition of the role of environmentally sensitive school design not only to improve learning environments but more specifically to engage children ecologically with their immediate built environment
Evaluation of the Effect of Nanographene Oxide on Microleakage of Conventional and Resin-Modified Glass Ionomer
No full textObjectives. One of the important features of the restorative materials is the ability to seal and prevent the microleakage. Glass ionomer cement (GIC) still exhibits some microleakage despite establishing a chemical bond to the tooth. The aim of this study was to evaluate the effect of nanographene oxide (nGO) on the microleakage of conventional (CGIC) and resin-modified glass ionomer cement (RMGIC). Methods. Thirty intact extracted molars were used. Class V cavities were prepared on their buccal and lingual surfaces. The samples randomly divided into two main groups of CGIC and RMGIC; each of them was randomly subdivided into three subgroups, including the group without nGO (control), the group with 1% nGO, and the group with 2% nGO. After restoring the cavities, they were subjected to thermocycling (1,000 cycles at 5/55°C). Two percent basic fuchsin solution was used to perform the microleakage test, and then the sectioned samples were examined by a stereomicroscope 40x. Kruskal–Wallis test, Dunn’s test, and Mann–Whitney U test were used to analyze the data (P<0.05). Results. Group CGIC + 1% nGO at the gingival margin and group RMGIC + 1% nGO at both gingival and occlusal margins had significantly less microleakage than their control groups (P=0.008, P=0.002, P=0.023, respectively). Also, in these two groups, there were no significant differences between the microleakage of the occlusal and gingival margins (P=0.132, P=0.511, respectively), while in all other groups, the gingival microleakage was significantly higher than that of occlusal microleakage. Conclusions. The addition of 1% nGO significantly reduced the gingival microleakage of CGIC and the occlusal and the gingival microleakage of RMGIC, while the addition of 2% nGO did not cause a significant reduction in microleakage
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