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In this study, similar aluminum alloys AA5052 with additional carbon fiber-reinforced polymer composite (CFRP) interlayer were selected to investigate the effect of welding parameters (rotational speed and dwell time) on the mechanical properties, joint efficiency, and microstructure of friction stir spot weld joint. The maximum tensile shear load was 1779.6 N with joint efficiency of 14.6% obtained at rotational speed of 2,000 rpm and 2 s dwell time, which is 39.5% higher than the value at low rotational speed 850 rpm and 2 s dwell time. Meanwhile, the maximum microhardness 58 HV was attained in the keyhole region at rotational speed of 2,000 rpm and dwell time of 5 s, which is 22.4% higher compared to low rotational speed. The SEM-EDS results reveal the presence of intermetallic compounds (Al-Mg-C), which enhance the intermetallic bonding between elements., NA

Luminescent solar concentrators (LSC) absorb large-area solar radiation and guide down-converted emission to solar cells for electricity production. Quantum dots (QDs) have been widely engineered at device and quantum dot levels for LSCs. Here, we demonstrate cascaded energy transfer and exciton recycling at nanoassembly level for LSCs. The graded structure composed of different sized toxic-heavy-metal-free InP/ZnS core/shell QDs incorporated on copper doped InP QDs, facilitating exciton routing toward narrow band gap QDs at a high nonradiative energy transfer efficiency of 66%. At the final stage of non-radiative energy transfer, the photogenerated holes make ultrafast electronic transitions to copper-induced mid-gap states for radiative recombination in the near-infrared. The exciton recycling facilitates a photoluminescence quantum yield increase of 34% and 61% in comparison with semi-graded and ungraded energy profiles, respectively. Thanks to the suppressed reabsorption and enhanced photoluminescence quantum yield, the graded LSC achieved an optical quantum efficiency of 22.2%. Hence, engineering at nanoassembly level combined with nonradiative energy transfer and exciton funneling offer promise for efficient solar energy harvesting., European Union (EU); Horizon 2020; European Research Council (ERC); Research and Innovation Programme

Phototherapies, in the form of photodynamic therapy (PDT) and photothermal therapy (PTT), are very promising treatment modalities for cancer since they provide locality and turn-on mechanism for toxicity, both of which are critical in reducing off-site toxicity. Irradiation of photosensitive agents demonstrated successful therapeutic outcomes; however, each approach has its limitations and needs to be improved for clinical success. The combination of PTT and PDT may work in a synergistic way to overcome the limitations of each method and indeed improve the treatment efficacy. The development of single photosensitive agents capable of inducing both PDT and PTT is, therefore, extremely advantageous and highly desired. Cyanine dyes are shown to have such potential, hence have been very popular in the recent years. Luminescence of cyanine dyes renders them as phototheranostic molecules, reporting the localization of the photosensitive agent prior to irradiation to induce phototoxicity, hence allowing image-guided phototherapy. In this review, we mainly focus on the cyanine dye-based phototherapy of different cancer cells, concentrating on the advancements achieved in the last ten years., NA

Minerals able to colour in blue (and green in combination with yellow pigments) are limited in number and geologically. After presenting a short history of the use of cobalt as a colouring agent of glass, glaze and enamel in the Western/Mediterranean, Islamic and Asian worlds since Antiquity, we will present the different forms (dissolved ions, natural and synthetic crystalline phases/pigments) of cobalt and associated elements regarding primary (transition metals) and secondary geological deposits (transition metals and/or arsenic, bismuth, silver). Attempts to identify the origin of cobalt have been made by many authors considering the associated elements but without considering the important modifications due to different processing of the raw materials (extraction/purification/formulation). We review the information available in the ancient reports and present literature on the use of cobalt, its extraction and production from the ores, the different geological sources and their relationship with associated elements (transition metals, bismuth, arsenic, and silver) and with technological/aesthetic requirements. (Partial) substitution of cobalt with lapis lazuli is also addressed. The relative application of non-invasive mobile Raman and pXRF analytical instruments, to detect mineral phases and elements associated with/replacing cobalt is addressed, with emphasis on Mamluk, Ottoman, Chinese, Vietnamese and Japanese productions. The efficiency of Ni-Zn-As diagram proposed by Gratuze et al. as a classification tool is confirmed but additionally, CoO-Fe2O3?MnO and CoO-NiO-Cr2O3 diagrams are also found as very efficient tools in this research. The relationship between the compositional data obtained from the artefacts and historical questions on the origin and date of their production are discussed in order to obtain a global historical view. The need of a better knowledge of (ancient) deposits of cobalt ores and the evolution of cobalt ore processing with time and p, French Agence Nationale de la Recherche ANR EnamelFC Project; Scientific and Technological Research Council of Turkey (TÜBİTAK)1001 Scientific and Technological Research Projects Funding Program

The prevalence of Parkinson's disease (PD) is increasing but the development of novel treatment strategies and therapeutics altering the course of the disease would benefit from specific, sensitive, and non-invasive biomarkers to detect PD early. Here, we describe a scalable and sensitive mass spectrometry (MS)-based proteomic workflow for urinary proteome profiling. Our workflow enabled the reproducible quantification of more than 2,000 proteins in more than 200 urine samples using minimal volumes from two independent patient cohorts. The urinary proteome was significantly different between PD patients and healthy controls, as well as between LRRK2 G2019S carriers and non-carriers in both cohorts. Interestingly, our data revealed lysosomal dysregulation in individuals with the LRRK2 G2019S mutation. When combined with machine learning, the urinary proteome data alone were sufficient to classify mutation status and disease manifestation in mutation carriers remarkably well, identifying VGF, ENPEP, and other PD-associated proteins as the most discriminating features. Taken together, our results validate urinary proteomics as a valuable strategy for biomarker discovery and patient stratification in PD.

Here, we report a new post-synthesis modification strategy for functionalizing reduced graphene aerogels (rGAs) towards an exceptional CO2 separation performance. 1-N-butyl-3-methylimidazolium hexafluorophosphate ([BMIM][PF6]) was impregnated on a rGA, prepared by reducing GA at 700 degrees C, at various ionic liquid (IL) loadings of 5, 10, 30, and 50 wt%. The resulting composites were characterized in deep detail by X-ray photoelectron spectroscopy, X-ray diffraction, N-2 physical adsorption measurements, scanning electron microscopy, Fourier transform infrared and Raman spectroscopies, and thermogravimetric analysis. Results indicated the presence of interactions between the rGA surface and the anion of the IL, potentially improving the CO2 affinity. Volumetric gas adsorption measurements using these materials showed that the deposition of [BMIM][PF6] on rGA surface at an IL loading of 50 wt% boosts the CO2/CH4 selectivity by more than 20-times, exceeding an absolute value of 120, a remarkably higher CO2/CH4 selectivity compared to that of other functionalized materials under similar operating conditions. Tunability of both the IL structure and the surface characteristics of rGA offer a tremendous degree of flexibility for the rational design of these IL/rGA composites towards high performance in gas separation applications., Scientific and Technological Research Council of Turkey (TÜBİTAK); Koç University Seed Fund Program; HEC-Pakistan Scholarship; TARLA; METU Prof. Dr. Mustafa N. Parlar Education and Research Foundation's 2019 Research Incentive Award

We incorporated a water-stable ionic liquid (IL), 1-butyl-3-methylimidazolium hexafluorophosphate, [BMIM][PF6], into a water-stable metal-organic framework (MOF), MIL-53(Al), to generate the [BMIM][PF6]/MIL-53(Al) composite. This composite was examined for water purification by studying its capacity for methylene blue (MB) and methyl orange (MO) removal from aqueous solutions having either single dye or a mixture of both. Data illustrated that the removal efficiency and the maximum adsorption capacity of MIL-53(Al) were increased several times upon [BMIM][PF6] incorporation. For instance, within 1 min, 10 mg of pristine MIL-53(Al) adsorbed 23.3% MB from 10 mg/L of MB solution, while [BMIM][PF6]/MIL-53(Al) composite was adsorbed 82.3% MB in an identical solution. In the case of MO, 10 mg of pristine MIL-53(Al) achieved 27.8 and 53.6% MO removal from 10 mg/L of MO solution, while [BMIM][PF6]/MIL-53(Al) composite removed 61.4 and 99.2% within 5 min and 3 h, respectively. Moreover, upon [BMIM][PF6] incorporation, the maximum MB and MO adsorption capacities of the pristine MOF were increased from 84.5 to 44 mg/g to 204.9 to 60 mg/g, respectively. The adsorption of dyes in pristine MIL-53(Al) and [BMIM][PF6]/MIL-53(Al) followed a pseudo-second-order kinetic model and a Langmuir isotherm model. In a mixture of both dyes, the IL/MOF composite showed a doubled MB selectivity after the IL incorporation. The composite was successfully regenerated at least two times after its use in water purification to remove MB, MO, and their mixtures. Infrared (IR) spectra indicated that the MB/MO adsorption occurs on [BMIM][PF6]/MIL-53(Al) by electrostatic interactions, hydrogen bonding, and pi-pi interactions. These results showed that [BMIM][PF6]/MIL-53(Al) composite is a highly promising material for efficient water purification., Scientific and Technological Research Council of Turkey (TÜBİTAK); Koç University Seed Fund Program

1-ethyl-3-methylimidazolium diethyl phosphate ([EMIM][DEP]) was incorporated into copper benzene-1,3,5-tricarboxylate, CuBTC. Consequences of molecular interactions on the CO2 separation performance of CuBTC were investigated. Scanning electron microscopy and X-ray diffraction results showed that the surface morphology and crystal structure of CuBTC remained intact upon the incorporation of the ionic liquid (IL); and the results of thermogravimetric analysis and infrared spectroscopy indicated the presence of interactions between the anion of the IL and the open metal sites of CuBTC. Gas adsorption measurements for the pristine CuBTC and IL-incorporated CuBTC were performed at 25 °C in a pressure range of 0.1–1 bar. Data showed that ideal CO2/CH4 and CO2/N2 selectivities of IL-incorporated CuBTC were 1.6- and 2.4-times higher compared to those of the pristine CuBTC at 0.01 bar, respectively. Moreover, for the CO2/CH4:50/50 and CO2/N2:15/85 mixtures, the corresponding selectivities were improved by more than 1.5- and 1.9-times compared to that of pristine CuBTC at 0.01 bar, respectively., Scientific and Technological Research Council of Turkey (TÜBİTAK); 1001- Scientific and Technological Research Projects Funding Program; European Union (EU); Horizon 2020; European Research Council (ERC) Research and Innovation Programme; COSMOS; Koç University Seed Fund Program; TARLA; HEC Pakistan Scholarship; METU Mustafa Parlar Foundation of Science and Education Incentive Award

Growing environmental problems along with the galloping rate of population growth have raised an unprecedented challenge to look for an ever-lasting alternative source of energy for fossil fuels. The eternal quest for sustainable energy production strategies has culminated in the electrocatalytic water splitting process integrated with renewable energy resources. The successful accomplishment of this process is thoroughly subject to competent, earth-abundant, and low-cost electrocatalysts to drive the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER), preferably, in the same electrolyte. The present contribution has been dedicated to studying the synthesis, characterization, and electrochemical properties of newfangled electrocatalysts with the formal composition of Mg1-xTMxB2 (x=0.025, 0.05, and 0.1; TM (transition metal)=Fe and Co) primarily in HER as well as OER under 1 M KOH medium. The electrochemical tests revealed that among all the metal-doped MgB2 catalysts, Mg0.95Co0.05B2 has the best HER performance showing an overpotential of 470 mV at-10 mA cm(-2) and a Tafel slope of 80 mV dec(-1) on account of its high purity and fast electron transport. Further investigation shed some light on the fact that Fe concentration and overpotential for HER have adverse relation meaning that the highest amount of Fe doping (x=0.1) displayed the lowest overpotential. This contribution introduces not only highly competent electrocatalysts composed of low-cost precursors for the water-splitting process but also a facile scalable method for the assembly of highly porous electrodes paving the way for further stunning developments in the field., Turkish Academy of Sciences (TUBA) Outstanding Young Scientist Award Program (GEBIP)

The aim of this research was to develop polymer-electrolyte membrane on the base of commercial polyimide Matrimid which has high proton conductivity at elevated temperatures above 100 °C. Hydrophobic ionic liquid 1-butylimidazolium bis(trifluoromethylsulfonyl)imide (BIM-TFSI) has been synthesized and used as proton conducting electrolyte. The electrical conductivity of the ionic liquid determined by electrochemical impedance method was found to have a value of 10–3 S/cm in the temperature range from 100 to 180 °С. The composite film based on Matrimid polyimide containing 70 wt % of protic ionic liquid has been prepared by casting from methylene chloride solution. Polyetheramine Jeffamine® D-2000 was used as a cross-linking agent for polyimide. According to mechanical and thermal analysis data, Matrimid/BIM-TFSI composite has tensile strength of 18 MPa and thermal degradation point of 306 °С. Electrophysical properties of polyimide film impregnated with ionic liquid was studied by two-probe technique at the frequencies of 0.1, 1.0 and 10 kHz by using immitance meter in the temperature range from 25 to 180 °С. The electrical conductivity was found to be 2.7∙10–4 S/cm at room temperature and reached the value of 1.5∙10–3 S/cm at 180 °С. Thus, in this work proton conducting membrane based on commercial polyimide has been obtained for the first time by simple method without additional sulfonation stage. Matrimid/BIM-TFSI composite membrane is promising for applications in fuel cells operating at elevated temperature without external humidification., Целью работы было получение полимер-электролитной мембраны на основе промышленного полиимида Matrimid с высоким уровнем протонной проводимости при температурах выше 100 °С. Синтезирована гидрофобная протонная ионная жидкость бис(трифторметилсульфонил)имид 1-бутилимидазолия (БИМ-ТФСИ), которая была использована в качестве протонпроводящего электролита. Удельная электропроводность ионной жидкости, измеренная методом электрохимического импеданса, имеет значение порядка 10–3 См/см в интервале температур 100–180 °С. Получена композитная пленка на основе полиимида Matrimid, содержащая 70 % ионной жидкости, поливом из раствора в метиленхлориде. Полиэфир Jeffamine® D-2000 использован в качестве сшивающего агента для полиимида. Согласно результатам механических и термических исследований, прочность на разрыв композита Matrimid/БИМ-ТФСИ составляет 18 мПа, а температура начала деструкции – 306 °С. Электрофизические свойства полиимидной пленки, насыщенной протонной ионной жидкостью, исследовали двухконтактным методом с помощью измерителя иммитанса на частотах 0.1, 1.0 и 10 кГц в температурном интервале 25–180 °С. Установлено, что удельная электропроводность материала составляет 2.7∙10–4 См/см при комнатной температуре, возрастая до величины 1.5∙10–3 См/см при 180 °С. Таким образом, в данной работе впервые получена протонобменная мембрана на основе коммерческого полиимида технологически простым методом, без дополнительной стадии сульфирования полимера. Композитная мембрана Matrimid/БІМ-ТФСІ перспективна для использования в топливных элементах, которые эксплуатируются при температурах выше 100 °С при отсутствии увлажнения., Метою роботи було отримання полімер-електролітної мембрани на основі промислового полііміду Matrimid з високим рівнем протонної провідності при температурі вище 100 °С. Синтезовано гідрофобну іонну рідину біс(трифторметилсульфоніл)імід 1-бутилімідазолію (БІМ-ТФСІ), яку використано в якості протонпровідного електроліту. Питома електропровідність іонної рідини, визначена методом електрохімічного імпедансу, має значення порядку 10-3 См/см в інтервалі температур 100-180 °С. Отримано композитну плівку на основі полііміду Matrimid із вмістом протонної іонної рідини 70 % поливом з розчину в метиленхлориді. Поліетерамін Jeffamine® D-2000 використано в якості зшиваючого агенту для полііміду. Згідно з результатами механічних і термічних досліджень, міцність на розрив композиту Matrimid/БІМ-ЕФСІ становить 18 мПа, а температура початку деструкції – 306 °С. Електрофізичні властивості поліімідної плівки, насиченої протонною іонною рідиною, досліджували двоконтактним методом за допомогою вимірювача іммітансу на частотах 0.1, 1.0 і 10 кГц в температурному інтервалі 25-180 °С. Встановлено, що питома електропровідність матеріалу становить 2.7 ∙ 10-4 См/см при кімнатній температурі, досягаючи величини 1.5 ∙ 10-3 См/см при 180 °С. Таким чином, в даній роботі вперше отримано протонобмінну мембрану на основі комерційного полііміду технологічно простим методом, без додаткової стадії сульфування полімеру. Композитна мембрана Matrimid/БІМ-ТФСІ перспективна для використання в паливних елементах, які експлуатуються при підвищених температурах за відсутності зволоження.

Abnormal behaviour of strong electrolytes was a hot research topic around the turn of twentieth century. In 1918, J. C. Ghosh published a series of articles dealing with this abnormal behaviour and suggested a cube root law for data correlation. The publications were both praised and criticised. Debye and Huckel published in 1923 their well-known theory of strong electrolytes, the square root law, which completely overshadowed Ghosh’s theory. By the middle of twentieth century, however, Ghosh’s theory became prominent again, particularly for concentrated electrolyte solutions, in the light of pseudo-lattice theory of strong electrolytes. In this article, we discuss some features and historical developments of Ghosh’s theory to commemorate its centenary year.

type:Journal Article, Sulfur-doped TiO2 was prepared by two methods; one was simple oxidation annealing of TiS2, the other was mixing of titanium isopropoxide and thiourea. These two sulfur-doped TiO2 preparations showed fairly different photocatalytic activity under visible light. The dynamics of photogenerated charge carriers were studied by the transient absorption measurement in the region of mid-IR. In both samples, excitation by 532 nm pulse led to photocarrier generation to the same extent. Nevertheless, the reactivity of the photocarriers was totally different. Photogenerated electrons and holes transferred to reactant gas in the latter sample, whereas they did not in the former sample. We attributed the different carrier behavior to the difference in the distribution of S atoms or particle size. These observations can explain the difference in capability of photocatalysis under visible light.

The article notes the features of applying the general equations of mathematical physics of an elliptic type in problems of modeling specific phenomena of the interaction of electromagnetic fields with elements and particles of an inhomogeneous dispersed medium. Such phenomena take place in installations for the separation of organic and mineral raw materials or the electromagnetic treatment of grain, seeds, etc. This is relevant, because the usual approach to the formulation of mathematical models in these problems, which is mainly based on differential equations of field theory in a simplified form, does not always adequately reflect the physical essence of the mentioned phenomena. Therefore, it limits the possibilities of an in-depth study of the influence of many factors determining the final results of separation and electromagnetic processing (EMP) processes. In the present work, an alternative approach is proposed based on the use of integral equations of field theory, which is based on the concept of primary and secondary field sources and can significantly reduce the order of the system of equations for the numerical implementation of algorithms for solving EMP problems, and the total amount of necessary computing resources. With this approach, local parameters of the field in interaction with individual particles and their influence on one another become available for calculation. This aspect is essential for determining the technological characteristics of EMP production installations. The presented mathematical model, in contrast to the common simplified approaches to determining the field parameters and ponderomotive forces acting on the particles of matter in the field, adequately reflects the physical laws of the distribution of potentials and electric field strength of real charges and induced sources. Due to this, it clearly reproduces the mechanism of the formation of the main components of mechanical forces acting on the polarized body from the si, В статье отмечены особенности применения общих уравнений математической физики эллиптического типа в задачах моделирования специфических явлений взаимодействия электромагнитных полей с элементами и частицами неоднородной дисперсной среды. Такие явления имеют место в установках сепарации органического и минерального сырья или электромагнитной обработки зерна, семян и проч. Это является актуальным, потому что обычный подход к формулировке математических моделей в указанных задачах, который базируется преимущественно на дифференциальных уравнениях теории поля в упрощенной форме, не всегда адекватно отражает физическую сущность упомянутых явлений. Поэтому он ограничивает возможности углубленного исследования влияния многих факторов, обусловливающих конечные результаты процессов сепарации и электромагнитной обработки (ЭМО). В представленной работе предложен альтернативный подход, построенный на использовании интегральных уравнений теории поля, который базируется на концепции первичных и вторичных источников поля и позволяет значительно уменьшить порядок системы уравнений при численном реализации алгоритмов решения задач ЭМО, и общий объем необходимых вычислительных ресурсов. При таком подходе оказываются доступными для расчета локальные параметры поля во взаимодействии с отдельными частицами и их влияние одной на другую. Указанный аспект является существенным для определения технологических характеристик производственных установок ЭМО. Представленная математическая модель, в отличие от распространенных упрощенных подходов к определению параметров поля и пондеромоторных сил, действующих в поле на частицы вещества, адекватно отражает физические закономерности распределения потенциалов и напряженности электрического поля реальных зарядов и индуцированных источников. Благодаря этому она наглядно воспроизводит механизм формирования главных составляющих механических усилий, действующих на поляризованное тело со стороны электрического поля в целом, через плотности элементарных, У статті виокремлено особливості застосування загальних рівнянь математичної фізики еліптичного типу в задачах моделювання специфічних явищ взаємодії електромагнітних полів з елементами і частинками неоднорідного дисперсного середовища. Такі явища мають місце в установках сепарації органічної та мінеральної сировини або електромагнітної обробки зерна, насіння та ін. Зазначене є актуальним, оскільки звичайний підхід до формулювання математичних моделей у наведених задачах, що базується переважно на диференціальних рівняннях теорії поля у спрощеній формі, не завжди адекватно відображає фізичну сутність згаданих явищ. Тому він обмежує можливості поглибленого дослідження впливу багатьох факторів, які обумовлюють кінцеві результати процесів сепарації та електромагнітної обробки (ЕМО). В роботі запропоновано альтернативний підхід, побудований на використанні інтегральних рівнянь теорії поля, який базується на концепції первинних і вторинних джерел поля і дозволяє значно зменшити порядок системи рівнянь при чисельній реалізації алгоритмів розв’язання задач ЕМО та загальний обсяг потрібних обчислювальних ресурсів. При такому підході виявляються доступними для обрахування локальні параметри поля у взаємодії з окремими частинками та їхнього впливу одне на одне. Зазначений аспект є суттєвим для визначення технологічних характеристик виробничих установок ЕМО. Представлена математична модель, на відміну від поширених спрощених підходів до визначення параметрів поля і пондеромоторних сил, що діють у полі на частинки речовини, адекватно відображає фізичні закономірності розподілу потенціалів і напруженості електричного поля реальних зарядів та індукованих джерел. Завдяки цьому вона наочно відтворює механізм формування головних складових механічних зусиль, що діють на поляризоване тіло з боку електричного поля в цілому, через щільність елементарних зусиль, які справляє поле на поверхневі заряди, що індукуються в діелектричних тілах у зоні дії полів. Така математична модель є універ

The aim of this study is to estimate the uncertainty of a portable X-ray fluorescence (p-XRF) instrument for the (semi-quantitative) analyses of tiles with underglaze decoration. Before starting the campaign of on-site measurements, the optimum acquisition time and the most accurate calibration mode were selected. For this purpose, the elemental composition of two glass standards of NIST (SRM610 and SRM612) and a Corning A standard were measured with varied times (5-360 s) and in different calibration modes (Mining, Mining Light Elements, Soil, and Rare Earth Elements). Afterwards, a set of blue-and-white tiles that was unearthed at Iznik Tile Kilns Excavation between the dig seasons of 2015 and 2019 was examined with p-XRF by selecting ten points of measure from each layer (body, transparent glaze, and blue coloured areas). The elemental composition of different layers was evaluated by means of the intragroup and intergroup data. They were also compared to the previous studies and found that the corrosion-free, homogeneous, and non-porous surfaces decrease the relative standard deviation (RSD) by increasing the consistency of the compositional data. The major elements found in the matrix of each layer (Al and Si for the body, Pb and Sn for the glaze) have the lowest value of RSD, as expected. However, the comparison of the data with the analysis of the reference materials showed that the content of Mg and also Si, which belong to the low-Z elements group, is shifted relatively towards the higher compositional values. The impossibility of measuring the elemental composition of sodium does not hinder the classification of the samples. Although the transition metals have very low concentrations, p-XRF measurements appear rather consistent and the intrinsic scattering of the data observed for a single artefact is largely smaller than those observed for the tiles of different historical buildings. Thus, it allows the classification to be made related to the different te, İstanbul University Scientific Research Projects Coordination Unit

Antimicrobial photodynamic therapy (aPDT) and antimicrobial photothermal therapy (aPTT) are promising local and effective alternative therapies for antibiotic resistant bacterial infections and biofilms. A combination of nanoparticles and organic photosensitizers offers a great opportunity to combine PDT and PTT for effective eradication of both planktonic bacteria and their biofilms. In this work, photo-induced antibacterial activity of indocyanine green (ICG), 3-aminopropylsilane coated superparamagnetic iron oxide nanoparticles (APTMS@SPIONs) and ICG loaded APTMS@SPIONs was evaluated on planktonic cells and biofilms of Gram-negative (E. coli,K. pneumoniae,P. aeruginosa) and Gram-positive (S. epidermis) bacteria. A relatively low dose of ICG (25 mu g mL(-1)) and SPIONs (0.425 mu g mL(-1)nanoparticle) in combination with single, short (10 min) laser irradiation at 808 nm with a power of 1150 mW was used in this study. No dark toxicity of the agents or antibacterial effect of the laser irradiation was observed. The charge of the particles did not provide a significant difference in their penetration to Gram-negativeversusGram-positive bacterial strains or their biofilms. APTMS@SPION/laser treatment completely eliminatedP. aeruginosaand provided 7-log reduction in the colony forming unit (CFU) ofE. Coli, but was not effective on the other two bacteria. This is the first example for antibacterial phototoxicity of this nanoparticle. ICG/laser and ICG-APTMS@SPION/laser treatments provided complete killing of all planktonic cells. Successful eradication of all biofilms was achieved with ICG/laser (3.2-3.7 log reduction in CFUs) or ICG-APTMS@SPION/laser treatment (3.3-4.4 log reduction in CFUs). However, an exceptionally high, 6.5-log reduction as well as a dramatic difference between ICGversusICG/APTMS@SPION treatment was observed inK. pneumoniaebiofilms with ICG-APTMS@SPION/laser treatment. Investigation of the ROS production and increase in the local temperature of the, Scientific and Technological Research Council of Turkey (TÜBİTAK)

Supported iridium complexes, Ir(C2H4)2/support, were characterized by X-ray absorption spectroscopy during a temperature ramp to 120 °C in flowing H2. Iridium in complexes bonded to weak and moderate electron-donor supports, SiO2and ?-Al2O3, underwent aggregation, forming nanoparticles and clusters, respectively. When the support was a strong electron-donor (MgO), iridium remained site-isolated. Density functional theory calculations confirm the dependence of iridium-support bond strength on the support's electron-donor character. Coating the SiO2-supported complexes with 1- n-ethyl-3-methyl-imidazolium acetate enhanced electron density on the iridium, hindering its aggregation. These results demonstrate opportunities for stabilizing atomically dispersed supported noble metals under reducing conditions by choice of support/ionic liquid sheath combinations., United States Department of Energy (DOE); University of California; Koç University TÜPRAŞ Energy Center (KUTEM); METU Prof. Dr. Mustafa N. Parlar Education and Research Foundation’s 2019 Research Incentive Award; TARLA

info:eu-repo/semantics/nonPublished

This study assesses the spatial and temporal characteristics of nighttime surface urban heat island (SUHI) effects over Greater Cairo: the largest metropolitan area in Africa. This study employed nighttime land surface temperature (LST) data at 1 km resolution from the Moderate Resolution Imaging Spectroradiometer (MODIS) Aqua sensor for the period 2003–2019. We presented a new spatial anomaly algorithm, which allowed to define SUHI using the most anomalous hotspot and cold spot of LST for each time step over Greater Cairo between 2003 and 2019. Results demonstrate that although there is a significant increase in the spatial extent of SUHI over the past two decades, a significant decrease in the mean and maximum intensities of SUHI was noted. Moreover, we examined the dependency between SUHI characteristics and related factors that influence energy and heat fluxes between atmosphere and land in urban environments (e.g., surface albedo, vegetation cover, climate variability, and land cover/use changes). Results demonstrate that the decrease in the intensity of SUHI was mainly guided by a stronger warming in daytime and nighttime LST in the neighborhood of urban localities. This warming was accompanied by a decrease in surface albedo and diurnal temperature range (DTR) over these areas. Results of this study can provide guidance to local urban planners and decision-makers to adopt more effective mitigation strategies to diminish the negative impacts of urban warming on natural and human environments.

[EN] The structure of xBaO·(1 − x) PO (x = 0.30, 0.35, 0.40, 0.45, and 0.50) glasses was studied by Raman spectroscopy and thermodynamic model Shakhmatkin and Vedishcheva (SVTDM). The seven system components (defined as stable crystalline phases of the BaO–PO binary phase diagram) were considered in the SVTDM: BaO, PO, 4BaO·PO (B4P), 3BaO·PO (B3P), 2BaO·PO (B2P), BaO·PO (BP), and BaO·2 PO (BP2). Only the equilibrium molar abundances of BP and BP2 were non-negligible in all studied glass compositions. Therefore, in the next step, multivariate curve analysis (MCR) of the baseline—subtracted, thermally—corrected experimental Raman spectra, was performed for two components (BP2 and BP). MCR resulted in the Raman spectra (loadings) and relative abundances (scores) of each considered component. The MCR method reproduced 98.93% of the spectral data variance. Then, the decomposition of Malfait was used. The perfect fit between the MCR loadings and the partial Raman spectra of BP2 and BP, obtained by Malfait’s decomposition, was found, confirming the validity of thermodynamic model.

Incorporation of ionic liquids (ILs) into metal-organic frameworks (MOFs) offers a broad potential in various applications. However, their applications in wastewater treatment have remained unexplored. Here, we investigate their potential in wastewater treatment and demonstrate a new concept of IL incorporation in ligand-functionalized MOFs, introducing IL/FMOFs. The composites were prepared by incorporating 1-n-butyl-3-methylimidazolium hexafluorophosphate, [BMIM][PF6], into UiO-66 and NH2-UiO-66 and tested for the adsorption of methylene blue (MB) and methyl orange (MO) from aqueous solutions. Data showed that NH2-functionalization and [BMIM][PF6] incorporation improved MB removal performance of UiO-66 by 16- and 48-times, as the capacity increased from 84.8 to 144.7 mg g(-1) and 174.1 mg g(-1), respectively. When considering both modifications together, [BMIM][PF6]/NH2-UiO-66 was almost 300 times faster than that of UiO-66, and the capacity exceeded 200 mg g(-1). Data further suggested that IL incorporation almost doubled MB/MO selectivity because of the strong electrostatic interactions and hydrogen bonding between [PF6](-) and MB, and pi-pi interactions between the [BMIM](+) cation and MB molecules. These results are the first to demonstrate the prospect of combining ligand functionalization with IL incorporation for modifying MOFs, introducing IL/FMOF composites for fast and selective removal of pollutants from wastewater., Scientific and Technological Research Council of Turkey (TÜBİTAK); TARLA

We demonstrate cuprous oxide (Cu2O) based screen engineered field effect solar cells with a record breaking efficiency, exceeding 3.486%, for Cu2O based p-n homojunction. In this architecture, CuO nanowire interphase is successfully employed in the Cu2O fabrication by effectively serving as a simultaneous ohmic current collector. These screen engineered field effect photovoltaic principles are essential in developing promising photovoltaics architectures for hard-to-dope materials that, in principle, enable extremely low-cost, high efficiency solar cells., Scientific and Technological Research Council of Turkey (TÜBİTAK); University of California

Nanoparticle based gene delivery systems holds great promise. Superparamagnetic iron oxide nanoparticles (SPIONs) are being heavily investigated due to good biocompatibility and added diagnostic potential, rendering such nanoparticles theranostic. Yet, commonly used cationic coatings for efficient delivery of such anionic cargos, results in significant toxicity limiting translation of the technology to the clinic. Here, we describe a highly biocompatible, small and non-cationic SPION-based theranostic nanoparticles as novel gene therapy agents. We propose for the first-time, the usage of the microRNA machinery RISC complex component Argonaute 2 (AGO2) protein as a microRNA stabilizing agent and a delivery vehicle. In this study, AGO2 protein-conjugated, anti-HER2 antibody-linked and fluorophore-tagged SPION nanoparticles were developed (SP-AH nanoparticles) and used as a carrier for an autophagy inhibitory microRNA, MIR376B. These functionalized nanoparticles selectively delivered an effective amount of the microRNA into HER2-positive breast cancer cell lines in vitro and in a xenograft nude mice model of breast cancer in vivo, and successfully blocked autophagy. Furthermore, combination of the chemotherapy agent cisplatin with MIR376B-loaded SP-AH nanoparticles increased the efficacy of the anti-cancer treatment both in vitro in cells and in vivo in the nude mice. Therefore, we propose that AGO2 protein conjugated SPIONs are a new class of theranostic nanoparticles and can be efficiently used as innovative, non-cationic, non-toxic gene therapy tools for targeted therapy of cancer., Scientific and Technological Research Council of Turkey (TÜBİTAK), 1003; Koç University

This joint issue of Optics Express and Optical Materials Express features 17 state-of-the art articles written by authors who participated in the international conference Advanced Solid-State Lasers held in Vienna, Austria, from September 29 to October 3, 2019. This introduction provides a summary of these articles that cover numerous areas of solid-state lasers from materials research to sources and from design to experimental demonstration., NA

Silicon nanowire-based sensors find many applications in micro- and nano-electromechanical systems, thanks to their unique characteristics of flexibility and strength that emerge at the nanoscale. This work is the first study of this class of micro- and nano-fabricated silicon-based structures adopting the scanning X-ray diffraction microscopy technique for mapping the in-plane crystalline strain (epsilon(044)) and tilt of a device which includes pillars with suspended nanowires on a substrate. It is shown how the micro- and nanostructures of this new type of nanowire system are influenced by critical steps of the fabrication process, such as electron-beam lithography and deep reactive ion etching. X-ray analysis performed on the 044 reflection shows a very low level of lattice strain (<0.00025 Delta d/d) but a significant degree of lattice tilt (up to 0.214 degrees). This work imparts new insights into the crystal structure of micro- and nanomaterial-based sensors, and their relationship with critical steps of the fabrication process., Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung (FWF)

We investigated the influences of the changes in the electronic structure and size of the anion of an imidazolium ionic liquid (IL) on gas adsorption and separation performance of the IL/ZIF-8 (zeolitic imidazolate framework) composites. We studied four different imidazolium ILs having the same cation, 1-n-butyl-3-methylimidazolium, [BMIM]+, with anions having structures allowing a systematic comparison of the changes in the electronic structure and size. To examine the influence of changes in the electronic structure, we considered anions representing the fluorination on the anion, methanesulfonate, [MeSO3]−, and trifluoromethanesulfonate, [CF3SO3]−. To investigate the change in the anion size, methyl sulfate, [MeSO4]−, and octyl sulfate, [OcSO4]−, were studied. Characterization of IL/ZIF-8 composites demonstrated successful incorporation of each IL in ZIF-8 without causing any detectable changes in the crystal structure and morphology of ZIF-8. Thermogravimetric analysis and infrared (IR) spectroscopy indicated the presence of direct interactions between ILs and ZIF-8, which directly control gas separation performance of the composite. Gas adsorption measurements illustrated that incorporation of ILs significantly improves the gas separation performance of the pristine ZIF-8. [BMIM][MeSO4]/ZIF-8 composite had 3.3- and 1.8-times higher CO2/N2 and CH4/N2 selectivities compared to ZIF-8, respectively, at 1 bar. When the IL has a fluorinated anion, CO2/CH4 selectivity improved 3-times compared to its non-fluorinated counterpart. Upon the incorporation of IL with a small anion, IL/ZIF-8 composite showed higher CO2/N2 and CH4/N2 selectivities compared to the composite having an IL with a bulky anion. These results will contribute in guiding rational design of IL/MOF composites for different gas separations., Scientific and Technological Research Council of Turkey (TÜBİTAK); 1001- Scientific and Technological Research Projects Funding Program; ERC-2017 -Starting Grant; European Research Council (ERC); European Union (European Union); Horizon 2020; Koç University Seed Fund Program; HEC-Pakistan Scholarship

There is an increasing demand for fast charging and high capacity lithium ion batteries. However, conventional Li-ion battery chemistries cannot meet the stringent requirements of these demands due to the poor performance of graphite anodes, especially on safety during fast charging. Finding the right anode material that can replace conventional graphite while providing high capacity is very challenging. Today, lithium titanium oxide (LTO) is considered one of the most attractive anode materials that can provide the desired ultra-fast charging ability (>10C) with high safety. However, it has many serious drawbacks when compared to the existing graphite anodes, including poor intrinsic conductivity, narrow electrochemical window, etc. Extensive research has been done to overcome these problems, especially in developing new LTO composite materials with reduced graphene oxide. However, even these methods have rapid capacity fading at high current densities, >5C, due to increased internal resistance and polarization losses. Here, we demonstrate an effective way to improve LTO composite materials by developing unique nanoengineered three-dimensional frameworks with hexagonal boron nitride (h-BN) addition. Li-ion cells with h-BN incorporation exhibit excellent performance and operational stability, especially at fast and ultra-fast charging rates, >10C., Next-Ion Energy, Inc.

Many animals collectively form complex patterns to tackle environmental difficulties. Several biological and physical factors, such as animal motility, population densities, and chemical cues, play significant roles in this process. However, very little is known about how sensory information interplays with these factors and controls the dynamics of pattern formation. Here, we study the direct relation between oxygen sensing, pattern formation, and emergence of swarming in active Caenorhabditis elegans aggregates. We find that when thousands of animals gather on food, bacteria-mediated decrease in oxygen level slows down the animals and triggers motility-induced phase separation. Three coupled factors-bacterial accumulation, aerotaxis, and population density-act together and control the entire dynamics. Furthermore, we find that biofilm-forming bacterial lawns including Bacillus subtilis and Pseudomonas aeruginosa strongly alter the collective dynamics due to the limited diffusibility of bacteria. Additionally, our theoretical model captures behavioral differences resulting from genetic variations and oxygen sensitivity., Scientific and Technological Research Council of Turkey (TÜBİTAK); ESRC Research Centre on Micro-Social Change at the University of Essex; Turkish Academy of the Sciences (Turkish Academy of Sciences (TÜBA)-GEBIP grant); Science Academy (BAGEP grant); British Academy

Colloidal quantum dots (QDs) are promising building blocks for luminescent solar concentrators (LSCs). For their widespread use, they need to simultaneously satisfy non-toxic material content, low reabsorption, high photoluminescence quantum yield, and large-scale production. Here, copper doping of zinc carboxylate-passivated InP core and nano-engineering of ZnSe shell facilitated high in-device quantum efficiency of QDs over 80%, having well-matched spectral emission profile with the photo-response of silicon solar cells. The optimized QD-LSCs showed an optical quantum efficiency of 37% and an internal concentration factor of 4.7 for a 10 × 10-cm2 device area under solar illumination, which is comparable with the state-of-the-art LSCs based on cadmium-containing QDs and lead-containing perovskites. Synthesis of the copper-doped InP/ZnSe QDs in gram-scale and large-area deposition (3,000 cm2) onto commercial window glasses via doctor-blade technique showed their scalability for mass production. These results position InP-based QDs as a promising alternative for efficient solar energy harvesting., European Research Council (ERC), European Union's Horizon 2020 Research and Innovation Programme; European Union (European Union); Horizon 2020; Turkish Academy of Sciences (TÜBA), TÜBA-Gedip The Young Scientist Award Program); Science Academy of Turkey (BAGEP; The Young Scientist Award Program)