Mühendislik Fakültesi

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3-State Protein Secondary Structure Prediction based on SCOPe Classes
(INST TECNOLOGIA PARANARUA PROF ALGACYR MUNHOZ MADER 3775-CIC, 81350-010 CURITIBA-PARANA, BRAZIL, 2021) Atasever, Sema; Azgınoglu, Nuh; Erbay, Hasan; Aydın, Zafer; 0000-0002-2295-7917; AGÜ, Mühendislik Fakültesi, Bilgisayar Mühendisliği Bölümü; Atasever, Sema
Abstract Improving the accuracy of protein secondary structure prediction has been an important task in bioinformatics since it is not only the starting point in obtaining tertiary structure in hierarchical modeling but also enhances sequence analysis and sequence-structure threading to help determine structure and function. Herein we present a model based on DSPRED classifier, a hybrid method composed of dynamic Bayesian networks and a support vector machine to predict 3-state secondary structure information of proteins. We used the SCOPe (Structural Classification of Proteins-extended) database to train and test the model. The results show that DSPRED reached a Q3 accuracy rate of 82.36% when trained and tested using proteins from all SCOPe classes. We compared our method with the popular PSIPRED on the SCOPe test datasets and found that our method outperformed PSIPRED.
4D-QSAR investigation and pharmacophore identification of pyrrolo[2,1-c][1,4]benzodiazepines using electron conformational–genetic algorithm method
(Taylor and Francis Ltd., 2016) Özalp, A.; Yavuz, S.Ç.; Sabancı, N.; Çapur, F.; Kökbudak, Z.; Sarıpınar, E.; AGÜ, Mühendislik Fakültesi, Bilgisayar Mühendisliği Bölümü; Çopur, Fatih
In this paper, we present the results of pharmacophore identification and bioactivity prediction for pyrrolo[2,1-c][1,4]benzodiazepine derivatives using the electron conformational–genetic algorithm (EC–GA) method as 4D-QSAR analysis. Using the data obtained from quantum chemical calculations at PM3/HF level, the electron conformational matrices of congruity (ECMC) were constructed by EMRE software. The ECMC of the lowest energy conformer of the compound with the highest activity was chosen as the template and compared with the ECMCs of the lowest energy conformer of the other compounds within given tolerances to reveal the electron conformational submatrix of activity (ECSA, i.e. pharmacophore) by ECSP software. A descriptor pool was generated taking into account the obtained pharmacophore. To predict the theoretical activity and select the best subset of variables affecting bioactivities, the nonlinear least square regression method and genetic algorithm were performed. For four types of activity including the GI50, TGI, LC50 and IC50 of the pyrrolo[2,1-c][1,4] benzodiazepine series, the r2 train, r2 test and q2 values were 0.858, 0.810, 0.771; 0.853, 0.848, 0.787; 0.703, 0.787, 0.600; and 0.776, 0.722, 0.687, respectively.
94.8 Km-Range Direct Detection Fiber Optic Distributed Acoustic Sensor
(IEEE, 345 E 47TH ST, NEW YORK, NY 10017 USA, 01.01.2019) Uyar, Faruk; Onat, Talha; Unal, Canberk; Unal, Canberk; Ozdur, Ibrahim; Ozbay, Ekmel; 0000-0003-3552-1650; AGÜ, Mühendislik Fakültesi, Elektrik - Elektronik Mühendisliği Bölümü
This work demonstrates an ultra-long range direct detection fiber optic distributed acoustic sensor which can detect vibrations at a distance of 94.8 km with 10 m resolution along the sensing fiber. (C) 2019 The Author(s)
Ab initio simulation of amorphous BC3
(Elsevier B.V., 2020) Durandurdu M.; AGÜ, Mühendislik Fakültesi, Malzeme Bilimi ve Nanoteknoloji Mühendisliği Bölümü
We report the structural and electrical properties of an amorphous BC3 model based on ab initio molecular dynamics simulations. The amorphous network is achieved from the melt and has a layer-like structure consisting of mainly hexagonal (six membered) rings as in the crystal. However, the distribution of boron atoms in the noncrystalline configuration appears to differ significantly from that of boron atoms in the crystal. The network is a solid solution and has randomly distributed nanosized graphene-like domains at each layer. Boron atoms have a tendency to form more overcoordinated defects involving with boron-boron homopolar bond(s). The mean coordination of boron and carbon atoms is 3.2 and 3.0, respectively. Interestingly the amorphous configuration is found to have a slightly higher density and bulk modulus than the crystal, which are attributed to the existence of overcoordinated units in the amorphous state. Based on the localization of the band tail states, noncrystalline BC3 is speculated to be a semiconducting material.
Ab initio study of boron-rich amorphous boron carbides
(WILEY, 2023) Yıldız, Tevhide Ayça; Durandurdu, Murat; 0000-0001-5636-3183; AGÜ, Mühendislik Fakültesi, Malzeme Bilimi ve Nanoteknoloji Mühendisliği Bölümü; Yıldız, Tevhide Ayça; Durandurdu, Murat
Amorphous boron carbide compositions having high B contents (BxC1−x, 0.50 ≤ x ≤ 0.95) are systematically created by way of ab initio molecular dynamics calculations, and their structural, electrical, and mechanical characteristics are inclusively investigated. The coordination number of both B and C atoms increases progressively with increasing B/C ratio and more close-packed materials having pentagonal pyramid motifs form. An amorphous diamond-like local arrangement is found to be dominant up to 65% B content, and beyond this content, a mixed state of amorphous diamond– and B-like structures is perceived in the models because sp3 hybridization around C atoms is still leading one for all compositions. The pentagonal pyramid motifs around C atoms are anticipated to appear beyond 65% content. The intericosahedral linear C–B–C chains do not form in any model. All amorphous boron carbides are semiconducting materials. The mechanical properties gradually increase with increasing B concentration, and some amorphous compositions are proposed to be hard materials on the basis of their Vickers hardness estimation.
Absolute phase noise analysis of a harmonically modelocked semiconductor laser
(Optica Publishing Group (formerly OSA), 2017) Ozharar, Sarper; Ozdur, Ibrahim; 0000-0001-6452-0804; AGÜ, Mühendislik Fakültesi, Elektrik - Elektronik Mühendisliği Bölümü; Ozdur, Ibrahim
We have designed and built a fiber coupled semiconductor laser at 1550 nm, which is harmonically mode-locked at 10 GHz by an external RF oscillator. The absolute phase noise of the laser is measured and discussed for two different cavity lengths.
Absorption enhancement by semi-cylindrical-shell-shaped structures for an organic solar cell application
(OPTICAL SOC AMER, 2010 MASSACHUSETTS AVE NW, WASHINGTON, DC 20036 USA, 2020) Hah, Dooyoung; 0000-0002-1290-0597; AGÜ, Mühendislik Fakültesi, Elektrik - Elektronik Mühendisliği Bölümü
Organic solar cells are attractive for various applications with their flexibility and low-cost manufacturability. In order to increase their attractiveness in practice, it is essential to improve their energy conversion efficiency. In this work, semi-cylindrical-shell-shaped structures are proposed as one of the approaches, aiming at absorption enhancement in an organic solar cell. Poly(3-hexylthiophene-2,5-diyl) blended with indene-C60 bisadduct (P3HT:ICBA) is considered as the active layer. Light coupling to the guided modes and a geometrical advantage are attributed to this absorption enhancement. Finite-difference time-domain methods and finite element analysis are used to examine the absorption spectra for two types of devices, i.e., a debossed type and an embossed type. It is shown that absorption enhancement increases as the radius of the cylinder increases, but reaches a saturation at about 4-mu m radius. The average absorption enhancement with an active layer thickness of 200 nm and radius of 4 mu m, and for incidence angles between 0 degrees and 70 degrees, is found as 51%-52% for TE-polarized input and as 30%-33% for TM-polarized input when compared to a flat structure. Another merit of the proposed structures is that the range of incidence angles where the integrated absorption is at the level of the normal incidence is significantly broadened, reaching 70 degrees-80 degrees. This feature can be highly useful especially when organic solar cells are to be placed around a round object. The study results also exhibit that the proposed devices bear broadband absorption characteristics. (C) 2020 Optical Society of America
An accurate investigation of the mechanical response and damage model of aluminum 7068
(Abdullah Gül Üniversitesi, 2018) Karaveli, Kadir Kaan; AGÜ, Mühendislik Fakültesi, Makine Mühendisliği Bölümü; Karaveli, Kadir Kaan
The promising combination of high strength, high toughness, low density and corrosion resistivity have made aluminium (Al) alloys the material of choice in various applications, from buildings to aerospace, for decades. Especially, Al 7068 alloy is one of the recently developed materials used mostly in defence and automobile industries due to their exceptional mechanical properties. In this master thesis, the mechanical response and Johnson-Cook damage model of Al 7068-T651 alloy was investigated. Specifically, different Johnson-Cook damage parameters were determined for different application areas considering the maximum, minimum and average results. These damage parameters can be used for accurate Finite Element Analysis simulations. To determine these damage parameters tensile tests were conducted on notched and smooth specimen son both rolling direction and perpendicular to the rolling direction. The notch radius were selected as smooth, 0.4 mm, 0.8 mm and 2 mm to provide different stress triaxiality values and observe the mechanical response at these triaxiality values. Tensile tests were repeated seven times to obtain the accurate results. The final cross-sectional areas of fractured specimens were calculated through optical microscopy. The effects of stress triaxiality factor and rolling direction on the mechanical properties of Al 7068-T651 alloy were successfully investigated. All damage parameters were calculated via LevenbergMarquardt optimization method. Overall, three different Johnson-Cook damage parameters based on minimum, average and maximum equivalent strain values were calculated. These Johnson-Cook ii damage parameters can be utilized for the accurate damage simulations of different applications in Finite Element Analysis, which is a computational technique and is used to obtain approximate solution of several engineering problems
Accurate Prediction of Residual Stresses in Machining of Inconel 718 Alloy through Crystal Plasticity Modelling
(Afyon Kocatepe Üniversitesi, 2023) Kesriklioglu, Sinan; Kapci, Mehmet Fazil; Büyükçapar,Rıdvan; Çetin , Barış; Yılmaz, Okan Deniz; Bal, Burak; 0000-0002-2914-808X; 0000-0003-3297-5307; 0000-0002-2550-7911; 0000-0002-7389-9155; AGÜ, Mühendislik Fakültesi, Makine Mühendisliği Bölümü; Kesriklioglu, Sinan; Kapci, Mehmet Fazil; Büyükçapar, Rıdvan; Bal, Burak
Determination and assessment of residual stresses are crucial to prevent the failure of the components used in defense, aerospace and automotive industries. The objective of this study is to present a material method to accurately predict the residual stresses induced during machining of Inconel 718. Orthogonal cutting tests were performed at various cutting speeds and feeds, and the residual stresses after machining of Inconel 718 were characterized by X-ray diffraction. A viscoplastic self-consistent crystal plasticity model was developed to import the microstructural inputs of this superalloy into a commercially available finite element software (Deform 2D). In addition, same simulations were carried out with classical Johnson - Cook material model. The simulation and experimental results showed that the crystal plasticity based multi-scale and multi-axial material model significantly improved the prediction accuracy of machining induced residual stresses of Inconel 718 when compared to the existing model, and it can be used to minimize the surface defects and cost of production trials in machining of difficult-to-cut materials.
Activation of methane by Os+: Guided-ion-beam and theoretical studies
(CHEMM, 2013) Armentrout P.B.; Parke, Laura; Hinton, Christopher; Citir, Murat; 0000-0002-7957-110X; AGÜ, Mühendislik Fakültesi, Malzeme Bilimi ve Nanoteknoloji Mühendisliği Bölümü; Citir, Murat
Activation of methane by the third-row transition-metal cation Os + is studied experimentally by examining the kinetic energy dependence of reactions of Os+ with CH4 and CD4 using guided-ion-beam tandem mass spectrometry. A flow tube ion source produces Os+ in its electronic ground state and primarily in the ground spin-orbit level. Dehydrogenation to form [Os,C,2 H]++H2 is exothermic, efficient, and the only process observed at low energies for reaction of Os+ with methane, whereas OsH+ dominates the product spectrum at higher energies. The kinetic energy dependences of the cross sections for several endothermic reactions are analyzed to give 0K bond dissociation energies (in eV) of D0(Os+-C)=6.20±0. 21, D0(Os+-CH)=6.77±0.15, and D0(Os +-CH3)=3.00±0.17. Because it is formed exothermically, D0(Os+-CH2) must be greater than 4.71eV, and a speculative interpretation suggests the exothermicity exceeds 0.6eV. Quantum chemical calculations at the B3LYP/def2-TZVPP level show reasonable agreement with the experimental bond energies and with previous theoretical values available. Theory also provides the electronic structures of the product species as well as intermediates and transition states along the reactive potential energy surfaces. Notably, the structure of the dehydrogenation product is predicted to be HOsCH+, rather than OsCH2+, in contrast to previous work.
Active control of the nanoparticle self-assembly for photonic applications
(META Conference, 2023) Erdem, Talha; 0000-0003-3905-376X; AGÜ, Mühendislik Fakültesi, Elektrik - Elektronik Mühendisliği Bölümü; Erdem, Talha
Colloidal nanoparticles enable collective utilization of the inherent properties of the nanoparticles. Furthermore, their collective optical response can be fine-tuned employing DNA-driven self-assembly. Here, we present that the optical transmission of self-assembled DNA-functionalized gold nanoparticle network can be actively manipulated using an external optical excitation. We also show control of optical polarization of emitted light from semiconducting supraparticle networks hybridized with magnetic supraparticles. These results prove the potential of programmed nanoparticle self-assembly in tailoring optical features of colloidal systems.
Active Subnetwork GA: A Two Stage Genetic Algorithm Approach to Active Subnetwork Search
(BENTHAM SCIENCE PUBL LTDEXECUTIVE STE Y-2, PO BOX 7917, SAIF ZONE, 1200 BR SHARJAH, U ARAB EMIRATES, 2017) Ozisik, Ozan; Bakir-Gungor, Burcu; Diri, Banu; Sezerman, Osman Ugur; AGÜ, Mühendislik Fakültesi, Bilgisayar Mühendisliği Bölümü; Bakir-Gungor, Burcu
Background: A group of interconnected genes in a protein-protein interaction network that contains most of the disease associated genes is called an active subnetwork. Active subnetwork search is an NP-hard problem. In the last decade, simulated annealing, greedy search, color coding, genetic algorithm, and mathematical programming based methods are proposed for this problem. Method: In this study, we employed a novel genetic algorithm method for active subnetwork search problem. We used active node list chromosome representation, branch swapping crossover operator, multicombination of branches in crossover, mutation on duplicate individuals, pruning, and two stage genetic algorithm approach. The proposed method is tested on simulated datasets and Wellcome Trust Case Control Consortium rheumatoid arthritis genome-wide association study dataset. Our results are compared with the results of a simple genetic algorithm implementation and the results of the simulated annealing method that is proposed by Ideker et al. in their seminal paper. Results and Conclusion: The comparative study demonstrates that our genetic algorithm approach outperforms the simple genetic algorithm implementation in all datasets and simulated annealing in all but one datasets in terms of obtained scores, although our method is slower. Functional enrichment results show that the presented approach can successfully extract high scoring subnetworks in simulated datasets and identify significant rheumatoid arthritis associated subnetworks in the real dataset. This method can be easily used on the datasets of other complex diseases to detect disease-related active subnetworks. Our implementation is freely available at https://www.ce.yildiz.edu.tr/personal/ozanoz/file/6611/ActSubGA
Adaptive Fault Detection Scheme Using an Optimized Self-healing Ensemble Machine Learning Algorithm
(CHINA ELECTRIC POWER RESEARCH INST, 2022) Yavuz, Levent; Soran, Ahmet; Onen, Ahmet; Li, Xiangjun; Muyeen, S. M.; 0000-0003-1398-9447; AGÜ, Mühendislik Fakültesi, Elektrik - Elektronik Mühendisliği Bölümü; Yavuz, Levent; Soran, Ahmet
This paper proposes a new cost-efficient, adaptive, and self-healing algorithm in real time that detects faults in a short period with high accuracy, even in the situations when it is difficult to detect. Rather than using traditional machine learning (ML) algorithms or hybrid signal processing techniques, a new framework based on an optimization enabled weighted ensemble method is developed that combines essential ML algorithms. In the proposed method, the system will select and compound appropriate ML algorithms based on Particle Swarm Optimization (PSO) weights. For this purpose, power system failures are simulated by using the PSCAD-Python co-simulation. One of the salient features of this study is that the proposed solution works on real-time raw data without using any pre-computational techniques or pre-stored information. Therefore, the proposed technique will be able to work on different systems, topologies, or data collections. The proposed fault detection technique is validated by using PSCAD-Python co-simulation on a modified and standard IEEE-14 and standard IEEE-39 bus considering network faults which are difficult to detect.
Admissible invariants of genus 3 curves
(Springer New York LLC, 2015) Cinkir, Zubeyir; AGÜ, Mühendislik Fakültesi, Endüstri Mühendisliği Bölümü; Çinkir, Zübeyir
Several invariants of polarized metrized graphs and their applications in Arithmetic Geometry are studied recently. In this paper, we explicitly calculated these admissible invariants for all curves of genus 3. We find the sharp lower bound for the invariants φ, λ and ε for all polarized metrized graphs of genus 3. This improves the lower bound given for Effective Bogomolov Conjecture for such curves.
Advanced tunability of optical properties of CdS/ZnSe/ZnTe/CdSe multi-shell quantum dot by the band edge engineering
(ELSEVIER, 2022) Koc, Fatih; Kavruk, Ahmet Emre; Sahin, Mehmet; 0000-0002-9419-1711; AGÜ, Mühendislik Fakültesi, Malzeme Bilimi ve Nanoteknoloji Mühendisliği Bölümü; Şahin, Mehmet
In this study, the advanced manipulability of wave functions in a type-II multi-shell hetero-nanostructure (MS-HNS) and the tunability of radiative exciton lifetime over a wide range with and/or without changing in transition energies has been demonstrated by the band edge engineering. For this purpose, the electronic and optical properties of exciton (X) and biexciton (XX) in a spherical CdS/ZnSe/ZnTe/CdSe HNS have been explored in detail. In the calculations, effects of all Coulombic interactions between the charges have been taken into account on the wave functions. Moreover, in the case of XX, the exchange–correlation potential between the same charged particles has also been considered. The results have been presented as a function of CdS core radius and ZnSe shell thickness and the probable physical reasons have been discussed in detail.
Advances in the computation of nmr parameters for inorganic nuclides
(ELSEVIER, 2023) Holmes, Sean T.; Alkan, Fahri; Dybowski, Cecil; 0000-0002-4046-9044; AGÜ, Mühendislik Fakültesi, Malzeme Bilimi ve Nanoteknoloji Mühendisliği Bölümü; Alkan, Fahri
In this article, we discuss practical aspects of the computation of NMR parameters of inorganic nuclides, as well as insights afforded by such calculations into the characterization of molecular-level structure and dynamics and the validation of theoretical models. An emphasis is placed on calculation of the magnetic shielding tensors of solids using cluster-based models that account for intermolecular interactions. In particular, the use of valence modification of terminal atoms using bond valence theory (VMTA/BV), which reduces net charges on clusters through terminal pseudoatoms with nonstandard nuclear charges, is demonstrated to be a robust technique for calculations on nuclei in network solids. Cluster-based calculations, including those that employ the VMTA/BV method, afford a unique opportunity to calculate magnetic shielding tensors for nuclei in solids by using density functional theory approximations beyond the generalized gradient approximation and by incorporating relativistic effects at the spin-orbit level. These developments are spurred by use of the zeroth-order regular approximation (ZORA), which provides a robust method of accounting for relativistic effects (up to the spin-orbit level) experienced by valence electrons. Calculations of NMR parameters are discussed for fluorine, cadmium, tin, tellurium, mercury, lead, and platinum, all of which have seen significant advances in recent years. These examples highlight the importance of such factors as coordination geometry, oxidation state, relativistic effects, and density functional approximations on computed magnetic shielding tensors.
Advantage of co-culture strategy for targeted cancer treatment and in vitro studies
(ELSEVIERRADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS, 2021) Bayram, Nurun Nisa; Isoglu, Sevil Dincer; Baran, Yael; Ulu, Gizem Tugce; AGÜ, Mühendislik Fakültesi, Malzeme Bilimi ve Nanoteknoloji Mühendisliği Bölümü; Bayram, Nurun Nisa; Isoglu, Sevil Dincer
Advantage of co-culture strategy for targeted cancer treatment and in vitro studies
Aerial Swarms: Recent Applications and Challenges
(Springer, 2021) Mohamed Abdelkader; Samet Güler; AGÜ, Mühendislik Fakültesi, Elektrik - Elektronik Mühendisliği Bölümü; Güler, Samet
Purpose of review: Currently, there is a large body of research on multi-agent systems addressing their different system theoretic aspects. Aerial swarms as one type of multi-agent robotic systems have recently gained huge interest due to their potential applications. However, aerial robot groups are complex multi-disciplinary systems and usually research works focus on specific system aspects for particular applications. The purpose of this review is to provide an overview of the main motivating applications that drive the majority of research works in this field, and summarize fundamental and common algorithmic components required for their development. Recent findings: Most system demonstrations of current aerial swarms are based on simulations, some have shown experiments using few 10 s of robots in controlled indoor environment, and limited number of works have reported outdoor experiments with small number of autonomous aerial vehicles. This indicates scalability issues of current swarm systems in real world environments. This is mainly due to the limited confidence on the individual robot's localization, swarm-level relative localization, and the rate of exchanged information between the robots that is required for planning safe coordinated motions. Summary: This paper summarizes the main motivating aerial swarm applications and the associated research works. In addition, the main research findings of the core elements of any aerial swarm system, state estimation and mission planning, are also presented. Finally, this paper presents a proposed abstraction of an aerial swarm system architecture that can help developers understand the main required modules of such systems.
Aguhyper: a hyperledger-based electronic health record management framework
(PEERJ INC, 2024) Dedeturk, Beyhan Adanur; Bakir-Gungor, Burcu; 0000-0003-4983-2417; AGÜ, Mühendislik Fakültesi, Bilgisayar Mühendisliği Bölümü; Dedeturk, Beyhan Adanur; Bakir-Gungor, Burcu
The increasing importance of healthcare records, particularly given the emergence of new diseases, emphasizes the need for secure electronic storage and dissemination. With these records dispersed across diverse healthcare entities, their physical maintenance proves to be excessively time-consuming. The prevalent management of electronic healthcare records (EHRs) presents inherent security vulnerabilities, including susceptibility to attacks and potential breaches orchestrated by malicious actors. To tackle these challenges, this article introduces AguHyper, a secure storage and sharing solution for EHRs built on a permissioned blockchain framework. AguHyper utilizes Hyperledger Fabric and the InterPlanetary Distributed File System (IPFS). Hyperledger Fabric establishes the blockchain network, while IPFS manages the off-chain storage of encrypted data, with hash values securely stored within the blockchain. Focusing on security, privacy, scalability, and data integrity, AguHyper’s decentralized architecture eliminates single points of failure and ensures transparency for all network participants. The study develops a prototype to address gaps identified in prior research, providing insights into blockchain technology applications in healthcare. Detailed analyses of system architecture, AguHyper’s implementation configurations, and performance assessments with diverse datasets are provided. The experimental setup incorporates CouchDB and the Raft consensus mechanism, enabling a thorough comparison of system performance against existing studies in terms of throughput and latency. This contributes significantly to a comprehensive evaluation of the proposed solution and offers a unique perspective on existing literature in the field.
Air-stable, nanostructured electronic and plasmonic materials from solution-processable, silver nanocrystal building blocks
(American Chemical Society, 2014) Fafarman, Aaron T.; Hong, Sung-Hoon; Oh, Soong Ju; Caglayan, Humeyra; Ye, Xingchen; Diroll, Benjamin T.; Engheta, Nader; Murray, Christopher B.; Kagan, Cherie R.; 0000-0002-0656-614X; AGÜ, Mühendislik Fakültesi, Elektrik - Elektronik Mühendisliği Bölümü; Caglayan, Humeyra
Herein we describe a room-temperature, chemical process to transform silver nanocrystal solids, deposited from colloidal solutions, into highly conductive, corrosion-resistant, optical and electronic materials with nanometer-scale architectures. After assembling the nanocrystal solids, we treated them with a set of simple, compact, organic and inorganic reagents: ammonium thiocyanate, ammonium chloride, potassium hydrogen sulfide, and ethanedithiol. We find that each reagent induces unique changes in the structure and composition of the resulting solid, giving rise to films that vary from insulating to, in the case of thiocyanate, conducting with a remarkably low resistivity of 8.8 × 10-6 ·cm, only 6 times that of bulk silver. We show that thiocyanate mediates the spontaneous sintering of nanocrystals into structures with a roughness of less than 1/10th of the wavelength of visible light. We demonstrate that these solution-processed, low-resistivity, optically smooth films can be patterned, using imprint lithography, into conductive electrodes and plasmonic mesostructures with programmable resonances. We observe that thiocyanate-treated solids exhibit significantly retarded atmospheric corrosion, a feature that dramatically increases the feasibility of employing silver for electrical and plasmonic applications.

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