bluuebunny/crossref_metadata_2025_split huggingface dataset:
Resilient and reproducible processing for CZTSe solar cells in the range of 10%
Authors: Taskesen Teoman , Steininger Vincent , Chen Wenjian , Ohland Jörg , Mikolajczak Ulf , Pareek Devendra , Parisi Jürgen , Gütay Levent 
Published: July 2018

AbstractIn this paper, we present our route to fabricate Cu2ZnSnSe4 (CZTSe) thin films, which allows to achieve reproducible processing of kesterite absorber, that leads to efficiencies in the range of 10%. The article mainly focuses on the annealing process and demonstrates that controlling of the reactor pressure for selenization can be reliably used to tune the losses of volatile constituents in the absorber, enabling adjustments on the properties of the film and solar cell. The findings reveal a noteworthy resilience to small changes of the process parameters in the vicinity of optimum conditions. Interestingly, a certain pressure range for optimum Zn and Sn composition exists, which results in a broad and stable process window and enables reproducible processing of CZTSe with high power conversion efficiencies. The established process also allows simple upscaling of the device area and results in a power conversion efficiency of ≈ 8% on a large area of 2.85 cm2. The highest efficiencies achieved by our process are around 11% for smaller lab scale devices.
Mixed micellization study of dodecyltrimethylammonium chloride and cetyltrimethylammonium bromide mixture in aqueous/urea medium at different temperatures: Theoretical and experimental view
Authors: Mahbub Shamim , Rub Malik Abdul , Hoque Md. Anamul , Khan Mohammed Abdullah 
Published: July 2018

AbstractThe behavior of mixed micelle formation between two cationic surfactants‐dodecyltrimethylammonium chloride (DTAC) and cetyltrimethylammonium bromide (CTAB) in absence/attendance of urea has been investigated by means of conductivity measurements over temperature range of 298.15 to 318.15 K. Lower magnitudes of the critical micelle concentration from their ideal values imply the strong interaction between the studied amphiphiles. The micellar mole fraction (X1) on the basis of the different proposed model (Rubingh, Motomura & Rodenas) and the ideal micellar mole fraction (Xid) were evaluated, and estimated results imply the high contribution of CTAB in the mixed micelle formation that enhances with the augment of the mole fraction of the CTAB. The values of activity coefficients (f1 and f2) (less than unity) and negative values of the interaction parameter (β) in all cases signify the attractive interaction between the amphiphiles studied. Spontaneous mixed micelle formation between the studied amphiphiles (dodecyltrimethylammonium chloride and CTAB) was indicated by the negative magnitudes of free energy of micellization (ΔGm0). The negative values of excess free energy of micellization (ΔGex) indicate the higher stability of the mixed micelle compared with the single micelle. The standard enthalpy change of micellization (ΔHm0) and standard entropy change of micellization (ΔSm0) were also calculated and discussed.
High Hydrostatic Pressure Induces a Lipid Phase Transition and Molecular Rearrangements in Low‐Density Lipoprotein Nanoparticles
Authors: Lehofer Bernhard , Golub Maksym , Kornmueller Karin , Kriechbaum Manfred , Martinez Nicolas , Nagy Gergely , Kohlbrecher Joachim , Amenitsch Heinz , Peters Judith , Prassl Ruth 
Published: July 2018

AbstractLow‐density lipoproteins (LDL) are natural lipid transporter in human plasma whose chemically modified forms contribute to the progression of atherosclerosis and cardiovascular diseases accounting for a vast majority of deaths in westernized civilizations. For the development of new treatment strategies, it is important to have a detailed picture of LDL nanoparticles on a molecular basis. Through the combination of X‐ray and neutron small‐angle scattering (SAS) techniques with high hydrostatic pressure (HHP) this study describes structural features of normolipidemic, triglyceride‐rich and oxidized forms of LDL. Due to the different scattering contrasts for X‐rays and neutrons, information on the effects of HHP on the internal structure determined by lipid rearrangements and changes in particle shape becomes accessible. Independent pressure and temperature variations provoke a phase transition in the lipid core domain. With increasing pressure an interrelated anisotropic deformation and flattening of the particle are induced. All LDL nanoparticles maintain their structural integrity even at 3000 bar and show a reversible response toward pressure variations. The present work depicts the complementarity of pressure and temperature as independent thermodynamic parameters and introduces HHP as a tool to study molecular assembling and interaction processes in distinct lipoprotein particles in a nondestructive manner.
Bioinspired Nanozymes with pH‐Independent and Metal Ions‐Controllable Activity: Field‐Programmable Logic Conversion of Sole Logic Gate System
Authors: Han Lei , Zhang Haijiao , Li Feng 
Published: July 2018

AbstractIn nature, different environmental factors make organisms to be programmed into different forms. However, it is difficult and significant to realize the field‐programmable logic conversion of sole logic system for molecular logic gates. Here, the concept of pH‐programmable “logic conversion” on the single logic gate based on the peculiar enzyme‐mimicking activity is presented. Inspired by natural enzymes with high pH‐stability and metal ions‐stimulated activity, pH‐independent and metal ions‐controllable catalase mimics (Co3O4 nanozymes) are designed by protein‐directed method. Although pH cannot directly change the activity of nanozymes, pH can change the existence state of metal ions and then the electron transfer rate on nanozymes. So, versatile roles of metal ions for catalase‐like and electrocatalytic activities are discovered on the premise of pH‐independency. For the proof‐of‐concept, OR/INHIBIT‐ and INHIBIT/AND‐switchable logic gates are facilely constructed using pH as the environmental stimulus and metal ions as inputs. Hence, the transformation of logic gate functions is realized without the change of logic gate elements and input molecules. This contribution may not only broaden the species and application area of nanozymes, but also open novel avenues for the molecular logic conversion and the metal ions sensor.
Energy Performance and Aging of RDX‐based TiH2, MgH2 Explosive Composites
Authors: Xue Bing , Lin Moujin , Ma Honghao , Wang Yixin , Shen Zhaowu 
Published: July 2018

AbstractTwo typical binary metal hydrides, TiH2 and MgH2 were introduced into the RDX based explosive composites. Charges with different contents of metal hydride were evaluated through underwater explosion. Composite with 10 % MgH2 exhibited the best shockwave parameters, peak overpressure, specific impulse and specific shock energy of which promoted by 5.7 %, 7.0 % and 8.4 % respectively. Whereas, the specific bubble energy of composite with 10 % TiH2 showed the maximum enhancement of 5.5 %, and density specific energy of which increased significantly attributed to the large density of TiH2. Meanwhile, a 2‐year ambient storage test of metal hydride reactants and RDX‐metal hydride explosive composites was conducted to evaluate the safety and stability. X‐ray diffraction (XRD), thermogravimetry (TG) and differential thermal analysis (DTA) were then conducted to analyze the aged samples. Results revealed that TiH2 and its explosive composites showed an excellent storage stability due to the formation of thin TiO2 film. Whereas, mass fraction of Mg(OH)2 was found increasing with time in both MgH2 and its explosive composite, of which hydrolysis of MgH2 was the main mechanism. Moreover, Mg was found in aged MgH2 powder as a result of decomposition. The mechanical strength of aged charges of RDX based MgH2 explosive composite also degraded significantly ascribed to the released hydrogen.
Monitoring transient events in infrared spectra using local mode analysis
Authors: Massarczyk Matthias , Schlitter Jürgen , Kötting Carsten , Rudack Till , Gerwert Klaus 
Published: July 2018

AbstractTime‐resolved Fourier transformed infrared (FTIR) spectroscopy of chemical reactions is highly sensitive to minimal spatiotemporal changes. Structural features are decoded and represented in a comprehensible manner by combining FTIR spectroscopy with biomolecular simulations. Local mode analysis (LMA) is a tool to connect molecular motion based on a quantum mechanics simulation with infrared (IR) spectral features and vice versa. Here, we present the python‐based software tool of LMA and demonstrate the novel feature of LMA to extract transient structural details and identify the related IR spectra at the case example of malonaldehyde (MA). Deuterated MA exists in two almost equally populated tautomeric states separated by a low barrier for proton transfer so IR spectra represent a mixture of both states. By state‐dependent LMA, we obtain pure spectra for each tautomeric state occurring within the quantum mechanics trajectory. By time‐resolved LMA, we obtain a clear view of the transition between states in the spectrum. Through local mode decomposition and the band‐pass filter, marker bands for each state are identified. Thus, LMA is beneficial to analyze the experimental spectra based on a mixture of states by determining the individual contributions to the spectrum and motion of each state.
β‐Strand twisting/bending in soluble and transmembrane β‐barrel structures
Authors: Kikuchi Nobuaki , Fujiwara Kazuo , Ikeguchi Masamichi 
Published: July 2018

AbstractThe majority of β‐strands in globular proteins have a right‐handed twist and bend. The dominant driving force for β‐strand twisting is thought to be inter‐strand hydrogen bonds. We previously demonstrated that for water‐soluble proteins, both the twisting and bending of β‐strand are suppressed by the polar side chains of serine, threonine, and asparagine residues. To determine whether this also holds for transmembrane β‐strands, we calculated and statistically analyzed the twist and bend angles of four‐residue frames of β‐strands in both transmembrane and water‐soluble β‐barrel proteins with known three‐dimensional structures. In the case of transmembrane β‐strands, we found that twisting was suppressed even for frames not containing serine, threonine, or asparagine residues. The suppression of twisting in transmembrane β‐strands could be attributed to the propagation of the suppressive effect of serine, threonine, and asparagine residues within a frame to the neighboring, hydrogen‐bonded strands under the restriction that all strands in the closed barrel structure must have similar twist angles. A similar tendency was also observed for water‐soluble β‐barrel proteins. We previously showed that the dominant driving force for β‐strand bending is hydrophobic interactions involving aromatic residues within and outside the strand. Transmembrane β‐barrels have no hydrophobic core; however, rather hydrophilic residues predominate inside the barrel or the β‐strands of transmembrane β‐barrels have larger bend angles than those of water‐soluble β‐barrels. Our results reveal that, in transmembrane β‐barrel proteins, the glycine‐aromatic ring motif is important for generating the β‐strand bending necessary for barrel formation.
Power analysis for group supplier selection with multiple production lines
Authors: Pearn W.L. , Tai Y.T. , Wu Yu‐Wen , Wang Yuan‐An 
Published: July 2018

AbstractGroup supplier selection problem is a critical problem because outsourcing is an important issue for supply chain management. For the advanced production processes with extremely low fraction of defectives, typical supplier selection methods no longer work because any sample of reasonable size probably contains no defective items. Thus, process capability indices have been extensively used for advanced production processes to evaluate and measure whether the process meets the specifications and they also provide quality assurance. In the globally competitive production environment, processes involving multiple production lines are quite common due to economies of scale considerations. In this paper, we consider a group supplier selection problem for multi‐supplier and multi‐line, in which a supplier group containing the best suppliers is selected based on a multi‐line yield index
. To avoid the inflation of multiple comparisons, we apply the Bonferroni method and subtraction test statistic to tackle the group supplier selection problem. Critical values for testing procedure and required sample sizes for designated selection powers are obtained and tabulated. In addition, we apply multiple comparisons with the best method and compare the selection powers with the Bonferroni method for various power settings to provide more accurate group supplier decisions for real‐world applications.
The guaranteed adaptive c‐charts with estimated parameter
Authors: Vakilian Fatemeh , Amiri Amirhossein , Faraz Alireza 
Published: July 2018

AbstractThe performance of control charts with estimated parameters in Phase II depends on the accuracy of parameter estimation in Phase I. Estimation accuracy depends on the amount of data. Simulation results show that no realistic number of Phase I samples is available to ensure that the in‐control performance of control charts with estimated parameters is close to cases where the parameters are known. In this paper, the bootstrapping method is applied to adjust the control and warning limits of c‐charts with adaptive sampling schemes, such as variable sample size, variable sampling intervals, and variable parameters. The adjusted charts guarantee that the in‐control average adjusted time to signal is more than a certain amount with a predefined probability. In addition, the performance of the adjusted adaptive c‐charts is compared with the commonly used approach to design adaptive c‐charts.
A surrogate‐based iterative importance sampling method for structural reliability analysis
Authors: Tang Zhang‐Chun , Xia Yanjun 
Published: July 2018

AbstractIn this paper, a surrogate‐based iterative importance sampling (IS) method is proposed to efficiently evaluate failure probability (FP) of engineering structures. The surrogate is constructed by the training points centered at the most probable failure point (MPP), which is estimated by an approximate algorithm without any additional evaluations of the real limit state function (LSF), and the IS method using the estimated MPP is further obtained; and an iterative procedure combined with the surrogate and the IS method is finally proposed to improve the accuracy of the estimated result for the FP. Three numerical examples are employed to demonstrate the accuracy of the proposed method, and further, an inside flap of an aircraft is employed to demonstrate the practical application of the proposed method in engineering problems. The results show that the reasonable estimated result of the FP within the range of 10−3‐10−5 can be evaluated by the proposed method with only hundreds of the evaluations of the real LSF.
Time‐dependent density‐functional study of the photoabsorption spectrum of Au25(SC2H4C6H5)18 anion: Validation of the computational protocol
Authors: Baseggio Oscar , De Vetta Martina , Fronzoni Giovanna , Toffoli Daniele , Stener Mauro , Sementa Luca , Fortunelli Alessandro 
Published: July 2018

AbstractA validation study of the computational protocol for predicting the optical properties of Monolayer‐Protected metal Clusters (MPCs) using time‐dependent density‐functional theory is presented. The Au25(SC2H4Ph)18− MPC is chosen as a reference, due to the availability of both structural and optical experimental data. The effects of the geometry, the basis set, the exchange‐correlation functionals, and the use of simplified or experimental ligands on the optical properties of Au25(SC2H4Ph)18− are discussed critically. When such options are carefully selected, an almost quantitative matching between theory and experiment is obtained. Noteworthy, the use of a precise geometric structure proves to be both crucial and critical for an accurate prediction of the optical response of MPC systems, a feature which is not easy to achieve using current density‐functional theory approaches.
Examination and analysis of Indian silver punch‐marked coins employing WD‐XRF and other noninvasive techniques
Authors: Mamania Divija , Singh M.R. , Lal U.S. 
Published: July 2018

The archaeometallurgical analysis of ancient silver coins provides useful information regarding fabrication methodology, provenance, and trade route and explains large diversification in elementary composition, weight, and physical features. The present investigation deals with the chemical analysis and examination of the processing history of Indian punch‐marked silver coins dating to 400–200 bc. The chemical analysis was carried out by wavelength dispersive X‐ray fluorescence and X‐ray Diffraction (XRD). The microstructural examination was performed using field emission scanning electron microscope (FE‐SEM) and different phases were identified by Scanning Electron Microscopy coupled with Energy Dispersive X‐ray (SEM‐EDX) Spectroscopy. It was observed that all eight coins were manufactured with silver‐copper alloy. The ore used for obtaining silver was argentiferous galena, and cupellation was carried with perfection. The absence of slag inclusions as revealed by SEM examination indicated that coins (numbers 2, 4, 5, and 7) were cast from a molten state. The presence of Cu2O, CuO, and Ag2O on the surfaces of the coins was confirmed by XRD. The formed oxide layers provided protection and saved the coins from bulky corrosion products. The data reveal great divergence of coin surface from the composition of the core with the far better metallurgical process for refining of silver for this hoard.
Computational and Experimental FT‐ IR, NMR, UV‐Vis Spectral Studies of 5,5′‐((4‐chlorophenyl)methylene)bis(1,3‐dimethyl‐6‐(methylamino)pyrimidine‐2,4(1H,3H)‐dione)
Authors: Shukla Shraddha , Bishnoi Abha , Fatma Shaheen , Verma Anil Kumar , Devi Poornima 
Published: July 2018

AbstractSynthesis of a novel 5,5′‐((4‐chlorophenyl)methylene)bis(1,3‐dimethyl‐6‐(methylamino)pyrimidine‐2,4(1H,3H)‐dione) has been done, followed by respective characterization by various spectroscopic techniques viz FT‐IR, 1H‐NMR, 13C‐NMR, UV‐Vis spectroscopy and computational methods. The study of the structure was done by Density Functional Theory (DFT) at the theory level Becke3–Lee–Yang–Parr (B3LYP) functional and 6–31G (d, p) as basis set. A close examination of various structural and thermodynamic parameters, electrostatic potential, electrophilicity (ω), chemical potential (μ), chemical hardness (η) and max amount of electronic charge transfer (▵Nmax) was done for this compound. Natural bond orbital analysis was employed to study the hyper conjugative interactions occurring within the molecule that are responsible for the stability of the molecule. To study the chemically active sites in the molecule, local reactivity descriptors were also calculated. Electric dipole moment, polarizability and first static hyperpolarizability values have been investigated for the title compound. In addition to it, a discussion about correlation graphs between 1H‐NMR and 13C‐NMR spectroscopic values is also done.
ESIPT‐Based Dual Chemosensor for Sequential Detection of Cd2+/Zn2+ and Nucleoside Triphosphates in Water: Application in Logic Gates
Authors: Singh Harminder , Sharma Rashmi , Bhargava Gaurav , Kumar Subodh , Singh Prabhpreet 
Published: July 2018

AbstractHere in, novel excited state intramolecular charge transfer (ESIPT)‐modulated fluorophore based on diphenylpyrimidinone DPHQ has been designed and synthesized. DPHQ shows selective 8‐fold ‘turn‐on’ fluorescence response with Cd2+/Zn2+ in buffer (containing 1% CH3CN, pH 7.2) with low detection limits of 55.7/2.7 nM accompanied with a fluorescent colour change from colourless to cyan. DPHQ–Cd2+ ensemble undergo selective fluorescence quenching with nucleoside triphosphates but it is silent to nucleoside di‐and mono‐phosphates. It can detect 58.4 nM concentration of adenosine triphosphate (ATP). The binding mode and sensing mechanism of DPHQ with Cd2+/Zn2+ was supported by the change in optical behaviors, density functional theory (DFT) calculations and Job's plot. DPHQ was successfully used for construction of ‘Set‐Reset’ memorized logic devices and OR, INHIBIT logic gates. As practical applications of DPHQ, we utilized DPHQ for detection of Cd2+/Zn2+ in blood serum and quantification of Zn2+ in tap water samples.
Basicity of Some Pyridinophanes in Gas Phase and Acetonitrile – a DFT Study
Authors: Despotović Ines 
Published: July 2018

AbstractThe gas phase proton affinities and basicities of a [1.1.1]‐(2,6)‐pyridinophane and its derivatives having one ‐CH2‐ bridge replaced by ‐CH=CH‐ and ‐CH2‐CH2‐ are examined by the DFT B3LYP/6‐311+G(2df,p)//B3LYP/6‐31G(d) method. The calculated proton affinities are within the range of 253.8 and 294.8 kcal mol−1. The upper‐scale basicity is consequence of unfavorable steric interactions in neutral bases and diminishing of former in conjugate acids with forming of intramolecular hydrogen bonds (IMHB) being amplified by substitution in theparaposition of pyridine rings by electron‐releasing substituents. The inspection of the nature of IMHBs reveals that IMHB is of a bifurcated type with energy spanning a range between 5.7 and 7.4 kcal mol−1. The basicities of pyridinophanes are examined in acetonitrile. It is found that their pKa values span a range between 18.9 and 31.3 units.
RETRACTED: Shrinkable Nanotubes for Duplex Formation of Short Nucleotides
Authors: Kameta Naohiro , Akiyama Haruhisa 
Published: July 2018

AbstractMolecular monolayer nanotubes produced by self‐assembly of an amphiphile modified with a 2‐nitrobenzyl group as a photoresponsive unit are able to encapsulate dinucleotides via electrostatic attraction. Upon photoirradiation, the 18 nm inner diameter of the nanotubes shrinks to less than 2 nm as a result of photochemical cleavage of the 2‐nitrobenzyl group in the amphiphile. This shrinking of the nanotube channels leads to a propulsive release of the dinucleotides into the bulk solution and simultaneously accelerates formation of the dinucleotide duplexes. The larger nanotube channels without photoirradiation merely release each dinucleotide into the bulk solution, indicating that the squeezing via transportation in the narrow nanotube channels is necessary for duplex formation. In addition to the size effect, water with a lower polarity confined within the narrow nanotube channels helps to stabilize the energetically unfavorable hydrogen‐bonded base pair between the dinucleotides. This system should enable researchers to perform biological reactions that occur only in specific environments and conditions in living organisms.