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Mixed PET Plastics Waste to Dimethyl Terephthalate & Ethylene Glycol
Get PDFPolyethylene terephthalate (PET) plastic is integral to our everyday lives. As the primary plastic used in food and beverage packaging and synthetic textiles (PET Resin Association, 2015), PET is produced in North America at a rate of 3.1 million tons per year. However, as of 2015, only 26.6% of the PET produced is being recycled per year (PET Resin Association, 2015). Thus, the accumulation of PET waste has become a significant environmental concern. To address this problem, this report proposes a methanolysis plant using technology from Eastman Chemical Company (Sharpe et al., 2020) to depolymerize 100,000 metric tons of PET plastic waste annually into dimethyl terephthalate (DMT) and ethylene glycol (EG). The process in this report uses a sodium carbonate catalyst with a methanol reagent at a temperature of 160°C and pressure of 250 psig for one hour, during which the PET polymer undergoes a transesterification reaction to produce DMT and EG. Various separation processes were included in the design to produce products of 99.8 wt% pure DMT and 99.1 wt% pure glycols (97.5 wt% EG). Preprocessing equipment was also included in the design to filter out impurities from the PET waste feedstock before it entered the reactors.
Based on a cost of capital of 15% and current prices of feedstock and products, economic analyses predicted a -$198MM net present value (NPV), return of investment (ROI) of –12.18% in year 3, and a negative internal rate of return (IRR). However, based on aggressive growth rate projections of the recycled PET market, it is possible but unlikely to reach a positive NPV of 677MM. Thus, although the process is not currently economically viable, it is likely that future uptake of sustainable plastics would make the process profitable
Collation Model for LJS 54: Cartolarii
Get PDFA brief explanation of the office of notary and the purpose of notarial documents (f. 1r), followed by transcriptions of deeds and acts arranged in subject order as examples for a notary drawing up a document. The numbering of books corresponding to subjects is frequently in error, and the manuscript was probably compiled for personal use by the notary Contarini (or Conticini). Subjects include loans, sale contracts, dowries, wills, confessions, and evidence. Deeds added at the end (f. 37v-40v) may be in multiple hands. A marginal note in a later hand is dated 1301 (f. 9r).https://repository.upenn.edu/sims_models/1050/thumbnail.jp
Collation Model for LJS 490: [Astronomical compendium]
Get PDFCollection of astronomical and astrological texts. Includes tables of solar declination (f. 13r), fixed stars (f. 22r), elevation of the pole star in various cities (f. 26r), new and full moons (f. 83r-84v), sightings and transits or eclipses of Venus and Mercury (f. 87r), and the position of the sun in the ecliptic (f. 87v); treatises on instruments, such as the astrolabe (f. 17r-22r, 29r-33v, 43r-49r, 50r-50v), the sundial (f. 23r-25v), the quadrant (f. 27r-28v, 78v), the Jacob\u27s staff (baculus, f. 45r-49r, 79r, 91r), and the chilinder or traveler\u27s dial (f. 77r-78v); treatises on other scientific subjects, such as practical geometry (f. 41r-42v), determination of the date of Easter (computus, f. 64v-67v, 70v-75r, 89r-90v), and analysis of urine (f. 68r-70r); digressions on the work of Johannes Sacrobosco (f. 35r-39r); and excerpts from the Compilatio de astrorum scientia of Leopold of Austria (f. 80r-81v). Cities in the Baden-Württemberg region of Germany are mentioned frequently, along with major cities in Europe, especially Italy.https://repository.upenn.edu/sims_models/1059/thumbnail.jp
Collation Model for Ms. Codex 1229: [Processional [manuscript] : Dominican use].
Get PDFA selection of texts and chants for use in a French Dominican convent, including the service for after the death and at the burial of a member of the order, and the processions for Palm Sunday, Maundy Thursday, Good Friday, Easter, the Ascension, Corpus Christi, the Assumption, and the Purification. The procession for Maundy Thursday is the distinctively Dominican observance of Washing of the Altars, in this case dedicated to the Trinity, Saint Dominic, Saint Margaret, the Virgin Mary, the Holy Cross, the Eucharist, and all saints. Liturgical directions in French refer to the women of the order and the Latin liturgical texts provide both feminine and masculine forms. The chant is in square notation on a 4-line staff. Notated text has been added in a later hand to the first and last leaves (f. 1v, 153r-154r) and informal notes in French also appear on the first leaf.https://repository.upenn.edu/sims_models/1088/thumbnail.jp
Collation Model for Ms. Codex 1096: [Wedding regulations]
Get PDFSumptuary regulations for betrothals and weddings (Hochzeitsordnung) issued by the city of Nuremberg, covering such details as how the announcement of the engagement (Lautmerung) should be made; how much the musicians should be paid; what guests may be invited; and what kind of food and wine may be served. The form of the regulations given in the codex includes an amendment made in April 1511 (f. 7v). An amendment concerning the permissibility of the bridegroom giving the bride a maiden-ring worth 10 gulden, which became part of the code in or before 1526, has been written in subsequently, or as an afterthought, in a similar hand (f. 4r).https://repository.upenn.edu/sims_models/1085/thumbnail.jp
Collation Model for Oversize Ms. Codex 78: [Miscellany of works on Catholic doctrine, canon law and religious life]
Get PDFContains six works generally concerned with Catholic doctrine, canon law and religious life, including a register of Peter Lombard\u27s four books of Sentences, together with an index to St. Augustine\u27s City of God and other notes. Also includes works by Nikolaus Jauer, Bartholomaeus de Ebraco and Caspar de Caldrinis, as well as two unattributed works.https://repository.upenn.edu/sims_models/1092/thumbnail.jp
Asymptotic Properties Of Disordered Systems
Get PDFThis thesis considers asymptotic behaviors of high-dimensional disordered systems, including Ising model and mean-field spin glass models. We first study the decay rate of correlations in the two-dimensional random field Ising model (RFIM). Second, we study the limit free energy of disordered systems.
For RFIM, we are interested in the two-dimensional case where the external field is of i.i.d centered Gaussian variables. We show that under nonnegative temperature, the effect of boundary conditions on the magnetization in a finite box decays exponentially in the side length of the box.
On the side of mean-field models, we use the Hamilton-Jacobi equation (HJE) approach, initiated by Jean-Christophe Mourrat, to characterize limiting free energy in many models from statistical inference problems and mean-field spin glass models. We now investigate infinite-dimensional models including many spin glass models and inference problems where the rank of the signal matrix increases as is sent to infinity. We give an intrinsic meaning to the Hamilton--Jacobi equation arising from mean-field spin glass models in the viscosity sense, and establish the corresponding well-posedness.This will shed more light on the mysterious Parisi formula as the limit of free energy in the Sherrington--Kirkpatrick model
Accelerated Design Of Architected Materials With Geometric Heterogeneity For Enhanced Failure Characteristics
Get PDFNature provides countless examples of the use of material heterogeneity to enhance the failure properties of materials. Many biological materials, such as bone, marine shells, and fish scales, are extremely resilient to fracture and failure. These often consist of regions that are highly mineralized and stiff and regions of biopolymers that are extremely soft. In practice, combining such disparate materials in synthetic systems is fraught with difficulties, such as poor interfacial adhesion. However, we will show, geometric heterogeneity can lead to similar enhancements to failure characteristics, including distribution of voids (inspired by bamboo) and spatial variations in fiber orientation (inspired by many materials, such as aorta). With the nearly arbitrary arrangements of materials that is enabled by 3D printing, it is possible to produce systems with bioinspired, spatially-varying microstructures that results in large improvements to failure properties. In this dissertation, I will discuss two types of geometric heterogeneities that can be easily introduced to architected materials enhancing their failure characteristics. First, inspired by the microstructure of the dactyl club of the Mantis shrimp, we show how geometric defects that are intrinsic to extrusion-based additive processes (voids and weak interfaces) can be spatially arranged in a helical (Bouligand) pattern to produce complex crack patterns and enhanced energy absorption. Next, we show how spatial variations in fiber orientation (inspired by aorta) can be produced using direct ink writing (DIW), leading to soft composites with high toughness and fatigue threshold. Such geometric heterogeneities in architected materials, and the 3D printing processes used to create them, introduce a large number of parameters into the material design process, such as infill layer angle, fiber orientation, void placement, etc. Bio-inspiration provides a starting point and some basic intuition about how to design heterogeneous materials for improved failure properties, but it cannot guarantee optimal failure properties. I will therefore conclude the talk with a discussion of the use of Bayesian optimization for the acceleration of the design of architected heterogeneous materials with optimal failure properties. We will introduce a multi-fidelity Bayesian optimization approach to accelerate the design of heterogeneous triangular lattices with maximal energy absorption during compressive loading
Machine Learning Under Endogeneity
Get PDFRecent advances in machine learning literature provide a series of new algorithms that both address endogeneity and can be applied in high-dimensional environments, we call them MLIV. These algorithms are data-driven and exploit various forms of regularization to ameliorate the ill-posedness of the problem while maintaining the functional form flexibility. In this thesis, we discuss how MLIV estimators can be used to answer economic questions.
In the first chapter, Causal Gradient Boosting: Boosted Instrumental Variables Regression, we propose an MLIV algorithm called boostIV that builds on the traditional gradient boosting algorithm and corrects for the endogeneity bias. The algorithm is very intuitive and resembles an iterative version of the standard 2SLS estimator. The second chapter, Automatic Debiased Machine Learning in Presence of Endogeneity, introduces an approach for performing valid asymptotic inference on regular functionals of MLIV estimators. The approach is based on construction of an orthogonal moment function that has a zero derivative with respect to the MLIV estimator. We develop a penalized GMM estimator of the bias correction term necessary to obtain asymptotically normal debiased estimates and derive its convergence rate. We also give conditions for root-n consistency and asymptotic normality of the debiased MLIV estimator of the functional of interest. Finally, in the third chapter, Flexible Demand Estimation using Machine Learning, we demonstrate how to estimate substitution patterns in the market for sodas using the debiasing procedure from the second chapter.
These three chapters are highly interconnected. The first chapter proposes a new MLIV algorithm for flexible estimation in presence of endogenous regressors. However, it focuses on the underlying structural function which in the majority of cases does not have a clear economic interpretation. While the second chapter develops a method to perform inference on functionals of MLIV estimators, which have a clear economic interpretation and can be used to answer various economic questions of interest. Finally, the third chapter investigates an important applied question of flexible estimation of demand for differentiated goods, which is a perfect example of a high-dimensional problem with endogenous regressors. As a result, we get a full picture about the potential of MLIV methods in economics
those Philly Muslims : Race, Islam, And The Search For Muslim Philadelphia
No full textThis project uses race as a lens to explore intra-Muslim relations among Black U.S. American and Arab American Sunni Muslims in “Muslim Philadelphia.” In it, I examine how racio-religious hierarchies inform social relations, subjectivities, and geographies in the city. I draw upon work theorizing race and Islam, especially in the U.S. (e.g., Khabeer 2016, 2009; Jackson 2013; Grewal 2013, 2006; Karim 2008, 2006, 2005; Jackson 2005); and I also develop my own theories of “ummah talk” and “race silence” to describe the ways race and the ummah are, and are not, talked about by Muslims and in Muslim spaces. Using data from my ethnographic fieldwork, I argue that Arab-Black and other intra-Muslim relations in Philadelphia are structured hierarchically in ways that both reflect and diverge from mainstream, U.S. racial logics. Following Jackson (2005) and Khabeer (2009), I call this unique racio-religious ideology and ordering, “Arab-immigrant supremacy” and ask how this system integrates elements of white supremacy, anti-Blackness, and global and regional orders. I use the term “Muslim Philadelphia” throughout to refer to the diverse population of Muslims who call Philadelphia, Pennsylvania, home and to the specific Islamic culture of the city, which despite this diversity is inextricable from Blackness