Chip seals are a pavement surface treatment used for maintaining asphalt concrete pavements. National Cooperative Highway Research Program (NCHRP) Project 14-17 was performed to produce a national Chip Seal Manual which would consolidate the best chip seal engineering practices. A subcontract to NCHRP Project 14-17 performed at Texas A&M University was the basis for this thesis. It included the following tasks: investigation of a testing and grading system for grading asphalt binder residues from chip seal emulsions; and investigation of texture measurement methods for assessing existing pavement macrotexture before a chip seal is placed. The performance graded (PG) asphalt binder specification, which was developed to characterize asphalt binder properties related to the performance of hot mix asphalt concrete in pavements, cannot be directly applied to asphalt binders or emulsion residues for use in chip seals. Therefore, the surface performance graded (SPG) specification was developed using the same equipment as the PG system but with some procedural modifications and different limiting values for the test parameters. NCHRP Project 14-17 utilized the PG and SPG systems to grade base asphalt binders and recovered emulsion residues. Two emulsion residue recovery methods were compared: hot oven evaporation with nitrogen blanket and stirred can with nitrogen purge. The PG and SPG grades were found to be similar for the two emulsion residue recovery methods but slightly different from the base asphalt binder. A strawman specification for emulsion residues in chip seals was recommended for use with the stirred can recovery method. In chip seal construction, macrotexture of the existing pavement affects the rate at which chip seal emulsion must be applied. In this project, existing pavement macrotextures were measured at three chip seal projects immediately before construction using both the sand patch test and the circular track meter, CT Meter. The CT Meter was found to quickly and effectively measure pavement macrotexture. The CT Meter measurements correlated well with the sand patch test measurements. Finally, this project investigated the utility of measuring pavement macrotexture in the laboratory using the aggregate imaging system (AIMS) on pavement cores and on small samples cut from fabricated slabs. Statistical analyses showed good correlation between the mean profile depth, MPD, calculated from AIMS measurements on pavement cores and small samples, based on analysis using 50 mm (2 inch) segment lengths, and the MPD measured on the pavement or on the large fabricated slabs with the CTMeter. These results supported the use of AIMS to measure pavement macrotexture using small samples in the laboratory.

In this thesis, it was aimed to select and propose a feasible method, or series of methods, for the recovery of zinc (Zn) and lead (Pb) that are present in disposed &Ccedil / iNKUR leach residues having 12.43 % Zn, 15.51 % Pb and 6.27 % Fe. Initially, physical, chemical and mineralogical characterizations of the leach residues were done. Results of these analyses showed that lead was present as lead sulfate (PbSO4), and zinc was present as zinc sulfate heptahydrate (ZnSO4.7H2O), zinc ferrite (ZnFe2O4) and zinc silicate (2ZnO.SiO2) in the leach residues. Initially, water leaching experiments were carried out to determine water soluble amount of blended leach residue, and the maximum zinc recovery was obtained as 18 %. After these trials, sulphuric acid and brine leaching were used to recover zinc and lead, respectively. Firstly, due to the insufficient recovery in water leaching trials acid leaching experiments were done for zinc recovery and the parameters studied were acid concentration, reaction duration, leaching temperature and solid-liquid ratio (pulp density). About 72 % Zn was recovered after hot acid leaching by using 150 g/l H2SO4 at 95 oC in 2 hours with a pulp density of 200 g/l. For lead recovery brine leaching experiments were done with the secondary leach residue obtained after H2SO4 leaching. In brine leaching experiments, NaCl concentration, pulp density (solid/liquid ratio), reaction duration and leaching temperature were chosen as variables. Effect of HCl addition was also investigated. In brine leaching while lead recoveries up to 98 % could be attained at a low pulp density in laboratory scale, the maximum recovery obtained was 84.9 % at a high pulp density (200 g/l) with 300 g/l NaCl concentration in 10 minutes at 95 oC.

The high-volume air sampling (PS-1) and micro-orifice uniformdeposit impactor (MOUDI) were used to measure the concentrations ofpolycyclic aromatic hydrocarbons (PAHs) in the atmosphere for fourseasons at Tuzo-Yin and Hsiung-Kong site in Kaohsiung city, in the airof a agricultural residue open burning area in Jhu-Shan and Sin-Gang siteduring the rice straw non-burning and burning periods, together with thesize distributions. Also, the receptor model was employed to determinethe potential sources of PAHs. The results show that the highest concentrations of PAHs occurred inwinter, being 143.9 ng/m3 and 182.9 ng/m3 at Tzuo-Yin and Hsiung-Kongsite, respectively; while the lowest concentrations of PAHs occurred insummer, being 81.4 ng/m3 and 95.2 ng/m3. The low-weight PAHs in thetwo sites were abundant in gaseous phase, being 43.8−96.7% and65.2−97.5% at Tzuo-Yin and Hsiung-Kong site, respectively. Meanwhile,the high-weight PAHs were almost present in particulate phase, being40.5−95.2% and 24.8−94.1 % at Tzuo-Yin and Hsiung-Kong site,respectively. The average PAHs concentrations were 330.04 and 567.81 ng/m3during the rice straw non-burning and burning period in Jhu-Shan site, theaverage PAHs concentrations were 427.16 and 571.80 ng/m3 during therice straw non-burning and burning period in Sin-Gang site, respectively,in the rice straw burning period, which were higher than those on thenon-burning days. The results of by CMB receptor modeling indicated that the major sources of pollution was exhaust emission (49.5−63.3%) in Tzuo-Yin site,and was burning source (49.1−63.7%) in Hsiung-Kong site in Kaohsiungcity. The results of APCA model analysis indicated that the major sourcesof pollution was mobile source (gasoline and diesel) were 66.5¡Ó8.0%during the rice straw non-burning period, and was mobile (gasoline) andrice straw non-burning source were 57.3¡Ó6.9% during the rice strawburning period in Jhu-Shan site in Central Taiwan. The results of APCAmodel analysis indicated that the major sources of pollution was mobile(gasoline) and plastics incinerator source were 54.3¡Ó6.4% during the ricestraw non-burning period, and was burning incense in temple, rice straw,mobile (gasoline and diesel) source were 50.7¡Ó4.6% during the rice strawburning period in Sin-Gang site in Central Taiwan.

The increased use of fossil fuels during the last centuries has caused elevated levels of carbon dioxide in the atmosphere. There is significant evidence that this is the cause of global warming. To mitigate the global warming, measures has to be taken to use renewable fuels and make processes more efficient. Catalytic gasification and downstream upgrading of synthesis gas is a promising technology for biofuel production, where previous research in black liquor gasification is currently expanding into a wider fuel feedstock. This work focuses on co-gasification of black liquor and by-products from other biofuel production technologies. The interesting by-products were crude glycerol from biodiesel production and spruce fermentation residue from ethanol production. The main goals were to study if the fuels can mix homogeneously and study the char reactivity. CO2 char gasification for mixtures of black liquor and glycerol or fermentation residue respectively was studied using thermogravimetric analysis (TGA) for four temperatures between 750°C and 900°C. The results show that glycerol can be mixed in all proportions with black liquor and indicate that the char reactivity is unchanged. The sustained char reactivity for blends is attributed to the volatility of glycerol. The fermentation residue does not produce a homogeneous mixture with black liquor and the char is less reactive. More studies should be performed to further elucidate the validity of the results.

The field of protein engineering has been greatly augmented by the expansion of the genetic code using unnatural amino acids as well as the development of cell-free synthesis systems with high protein yield. Cell-free synthesis systems have improved considerably since they were first described almost 40 years ago. Residue specific incorporation of non-canonical amino acids into proteins is usually performed in vivo using amino acid auxotrophic strains and replacing the natural amino acid with an unnatural amino acid analog. Herein, we present an amino acid depleted cell-free protein synthesis system that can be used to study residue specific replacement of a natural amino acid by an unnatural amino acid analog. This system combines high protein expression yields with a high level of analog substitution in the target protein. To demonstrate the productivity and efficacy of a cell-free synthesis system for residue-specific incorporation of unnatural amino acids in vitro, we use this system to show that 5-fluorotryptophan and 6-fluorotryptophan substituted streptavidin retain the ability to bind biotin despite protein wide replacement of a natural amino acid for the amino acid analog. We envisage this amino acid-depleted cell-free synthesis system being an economical and convenient format for the high-throughput screening of a myriad of amino acid analogs with a variety of protein targets for the study and functional characterization of proteins substituted with unnatural amino acids when compared to the currently employed in vivo format. We use this amino acid depleted cell-free synthesis system for the directed evolution of streptavidin, a protein that finds wide application in molecular biology and biotechnology. We evolve streptavidin using in vitro compartmentalization in emulsions to bind to desthiobiotin and find, at the conclusion of our experiment, that our evolved streptavidin variants are capable of binding to both biotin and desthiobiotin equally well. We also discover a set of mutations for streptavidin that are potentially powerful stabilizing mutations that we believe will be of great use to the greater research community. / text

Graphene is a promising material for flexible electronics due to its extraordinary electrical, mechanical, and optical properties. One of the biggest challenges today is to transfer large-scale graphene sheet to flexible substrates with minimal quality degradation. In this thesis, a bilayer polymer support for graphene transfer is proposed. Liquid PDMS (polydimethylsiloxane) is first coated on graphene to conform to its surface morphology. A flexible plastic substrate is then pressed on PDMS as a durable support. After PDMS is cured, electrochemical delamination is used to separate graphene from the copper foil. Due to the extremely low work of adhesion between graphene and PDMS, the graphene film on PDMS can be further transferred onto silicon wafer or other flexible substrates by simple adhesion. An added benefit of the PDMS layer is its strain isolation effect, which could protect graphene-based devices from breaking under external loads applied on the flexible substrate. The strain isolation effect of PDMS is verified with an analytical model and finite element analysis. The design of a prototype roll-to-roll graphene transfer machine is also presented. / text

The indeterminate nature of lentil (Lens culinaris Medik), in conjunction with adverse field conditions, can lead to varying degrees of maturity among plants at harvest. This variable maturity may have a negative influence on lentil production and can delay harvest. Desiccants are currently used to improve lentil crop dry-down. However, applying desiccants too early may result in reduced crop yield and quality, and also leave unacceptable herbicide residues in lentil seeds. In addition, only four herbicides (glyphosate, diquat, saflufenacil, and glufosinate) are registered as desiccants for lentil desiccation in Canada, which limits options for growers. Therefore, the objectives of this thesis were i) to determine the importance of desiccant application timing in affecting crop yield and quality, as well as herbicide residues and ii) to determine whether additional desiccants applied alone or tank-mixed with glyphosate provide better crop desiccation. Field trials were conducted at Saskatoon and Scott, Saskatchewan, from 2012 to 2014. In the application timing trial, glyphosate or saflufenacil alone, or glyphosate+saflufenacil generally decreased seed yield, thousand seed weight, and crop dry-down, and increased herbicide residue levels at earlier application timings. For example, when applied at 60% seed moisture, saflufenacil reduced yield and thousand seed weight by 22% and 10%, respectively, and resulted in glyphosate and saflufenacil residues greater than 2.0 and 0.03 ppm, respectively. Although there were no reductions in yield and thousand seed weight when desiccants were applied at 50% or 40% seed moisture, glyphosate residue exceeded 2.0 ppm. Application of desiccants at 20 or 30% seed moisture content had no effect on yield, thousand seed weight, or herbicide residues. These results indicate that desiccant application timing is critical, and should not be made before 30% seed moisture. In a second study, glufosinate and diquat tank mixed with glyphosate were the most consistent desiccants and provided optimal crop dry-down without reducing yield and thousand seed weight, and effectively reduced glyphosate residue. The other herbicides tested (pyraflufen-ethyl and flumioxazin) were found to be poor options for growers as they had sub-optimal crop desiccation and did not affect glyphosate residue.

This doctoral thesis approaches the problem of designing versatile architectures for cryptographic hardware. By the term versatile we define hardware architectures capable of supporting a variety of arithmetic operations and algorithms useful in cryptography, with no need to reconfigure the internal interconnections of the integrated circuit. A versatile architecture could offer considerable benefits to the end-user. By embedding a variety of crucial operations in a common architecture, the user is able to switch seamlessly the underlying cryptographic protocols, which not only gives an added value in the design from flexibility but also from practicality point of view. The total cost of a cryptographic application can be also benefited; assuming a versatile integrated circuit which requires no additional circuitry for other vital operations (for example input–output converters) it is easy to deduce that the total cost of development and fabrication of these extra components is eliminated, thus reducing the total production cost. We follow a systematic approach for developing and presenting the proposed versatile architectures. First, an in-depth analysis of the algorithms of interest is carried out, in order to identify new research areas and weaknesses of existing solutions. The proposed algorithms and architectures operate on Galois Fields GF of the form GF(p) for integers and GF(2^n) for polynomials. Alternative number representation systems such as Residue Number System (RNS) for integers and Polynomial Residue Number System (PRNS) for polynomials are employed. The mathematical validity of the proposed algorithms and the applicability of RNS and PRNS in the context of cryptographic algorithms is also presented. The derived algorithms are decomposed in a way that versatile structures can be formulated and the corresponding hardware is developed and evaluated. New cryptanalytic properties of the proposed algorithms against certain types of attacks are also highlighted. Furthermore, we try to approach a fundamental problem in Very Large Scale Integration (VLSI) design, that is the problem of evaluating and comparing architectures using models independent from the underlying fabrication technology. We also provide generic methods to evaluate the optimal operation parameters of the proposed architectures and methods to optimize the proposed architectures in terms of speed, area, and area x speed product, based on the needs of the underlying application. The proposed methodologies can be expanded to include applications other than cryptography. Finally, novel algorithms based on new mathematical and design problems for the crucial operation of modular multiplication are presented. The new algorithms preserve the versatile characteristics discussed previously and it is proved that, along with existing algorithms in the literature, they may forma large family of algorithms applicable in cryptography, unified under the common frame of the proposed versatile architectures. / Η παρούσα διατριβή άπτεται του θέματος της ανάπτυξης ευέλικτων αρχιτεκτονικών κρυπτογραφίας σε ολοκληρωμένα κυκλώματα υψηλής ολοκλήρωσης (VLSI). Με τον όρο ευέλικτες ορίζονται οι αρχιτεκτονικές που δύνανται να υλοποιούν πλήθος βασικών αριθμητικών πράξεων για την εκτέλεση κρυπτογραφικών αλγορίθμων, χωρίς την ανάγκη επαναπροσδιορισμού των εσωτερικών διατάξεων στο ολοκληρωμένο κύκλωμα. Η χρήση ευέλικτων αρχιτεκτονικών παρέχει πολλαπλά οφέλη στο χρήστη. Η ενσωμάτωση κρίσιμων πράξεων απαραίτητων στη κρυπτογραφία σε μια κοινή αρχιτεκτονική δίνει τη δυνατότητα στο χρήστη να εναλλάσσει το υποστηριζόμενο κρυπτογραφικό πρωτόκολλο, εισάγοντας έτσι χαρακτηριστικά ευελιξίας και πρακτικότητας, χωρίς επιπρόσθετη επιβάρυνση του συστήματος σε υλικό. Αξίζει να σημειωθεί πως οι εναλλαγές αυτές δεν απαιτούν τη παρέμβαση του χρήστη. Σημαντική είναι η συνεισφορά μιας ευέλικτης αρχιτεκτονικής και στο κόστος μιας εφαρμογής. Αναλογιζόμενοι ένα ολοκληρωμένο κύκλωμα που μπορεί να υλοποιεί αυτόνομα όλες τις απαραίτητες πράξεις ενός αλγόριθμου χωρίς την εξάρτηση από εξωτερικά υποσυστήματα (π.χ. μετατροπείς εισόδου–εξόδου), είναι εύκολο να αντιληφθούμε πως το τελικό κόστος της εκάστοτε εφαρμογής μειώνεται σημαντικά καθώς μειώνονται οι ανάγκες υλοποίησης και διασύνδεσης επιπρόσθετων υποσυστημάτων στο ολοκληρωμένο κύκλωμα. Η ανάπτυξη των προτεινόμενων αρχιτεκτονικών ακολουθεί μια δομημένη προσέγγιση. Διενεργείται εκτενής μελέτη για τον προσδιορισμό γόνιμων ερευνητικών περιοχών και εντοπίζονται προβλήματα και δυνατότητες βελτιστοποίησης υπαρχουσών κρυπτογραφικών λύσεων. Οι νέοι αλγόριθμοι που αναπτύσσονται αφορούν τα Galois πεδία GF(p) και GF(2^n) και χρησιμοποιούν εναλλακτικές αριθμητικές αναπαράστασης δεδομένων όπως το αριθμητικό σύστημα υπολοίπων (Residue Number System (RNS)) για ακέραιους αριθμούς και το πολυωνυμικό αριθμητικό σύστημα υπολοίπων (Polynomial Residue Number System (PRNS)) για πολυώνυμα. Αποδεικνύεται η μαθηματική τους ορθότητα και βελτιστοποιούνται κατά τέτοιο τρόπο ώστε να σχηματίζουν ευέλικτες δομές. Αναπτύσσεται το κατάλληλο υλικό (hardware) και διενεργείται μελέτη χρήσιμων ιδιοτήτων των νέων αλγορίθμων, όπως για παράδειγμα νέες κρυπταναλυτικές ιδιότητες. Επιπρόσθετα, προσεγγίζουμε στα πλαίσια της διατριβής ένα βασικό πρόβλημα της επιστήμης σχεδιασμού ολοκληρωμένων συστημάτων μεγάλης κλίμακας (Very Large Scale Integration (VLSI)). Συγκεκριμένα, προτείνονται μέθοδοι σύγκρισης αρχιτεκτονικών ανεξαρτήτως τεχνολογίας καθώς και τρόποι εύρεσης των βέλτιστων συνθηκών λειτουργίας των προτεινόμενων αρχιτεκτονικών. Οι μέθοδοι αυτές επιτρέπουν στον σχεδιαστή να παραμετροποιήσει τις προτεινόμενες αρχιτεκτονικές με βάση τη ταχύτητα, επιφάνεια, ή το γινόμενο ταχύτητα x επιφάνεια. Οι προτεινόμενες μεθοδολογίες μπορούν εύκολα να επεκταθούν και σε άλλες εφαρμογές πέραν της κρυπτογραφίας. Τέλος, προτείνονται νέοι αλγόριθμοι για τη σημαντικότατη για την κρυπτογραφία πράξη του πολλαπλασιασμού με υπόλοιπα. Οι νέοι αλγόριθμοι ενσωματώνουν από τη μία τις ιδέες των ευέλικτων δομών, από την άλλη όμως βασίζονται σε νέες ιδέες και μαθηματικά προβλήματα τα οποία προσπαθούμε να προσεγγίσουμε και να επιλύσουμε. Αποδεικνύεται πως είναι δυνατή η ενοποίηση μιας μεγάλης οικογένειας αλγορίθμων για χρήση στην κρυπτογραφία, υπό τη στέγη των προτεινόμενων μεθοδολογιών για ευέλικτο σχεδιασμό.

No description available.

The gas-phase hydrogen/deuterium (H/D) exchange of protonated di- and tripeptides containing a basic amino acid residue has been studied with a Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometer. Bimolecular reactions are monitored as a function of time providing exchange efficiencies and temporal distributions for the peptide ions. Results from these experiments indicated that position of the basic residue within the peptide (i.e. N-terminal, internal, or C-terminal) influences gas-phase H/D exchange, suggesting unique peptide ion conformations. The FT-ICR mass spectrometer employed for these gas-phase H/D exchange studies was modified from its original design. Instrument modifications include development of an internal matrix assisted laser desorption ionization (MALDI) source for peptide protonation. In addition, a two-section cell was utilized, allowing control of ion motion and factors affecting gas-phase ion molecule reactions. Systems investigated in these gas-phase H/D exchange studies are peptides containing the same amino acid residues but different sequences. These sequence isomers display dissimilar reaction efficiencies and temporal distributions for deuterium incorporation depending on the primary structure of the peptide ion. Specifically, [M+H]+ peptide ions containing a N-terminal basic residue demonstrate unique H/D exchange behavior when compared to their internal and C-terminal counterparts. These differences are attributed to dissimilar intramolecular bridging interactions involved with inductive stabilization of the charge site. Gas-phase H/D exchange of peptide sequence isomers was also probed with various deuterium reagents. Findings suggest that different reagents also influence H/D exchange reaction rate efficiencies and temporal distributions. These dissimilarities are ascribed to relative gas-phase basicity and proposed mechanistic exchange differences for the deuterium reagents.