Miracle-dz/UniFAR-FTUs huggingface dataset:
Kinematic diffraction from a mathematical viewpoint

Abstract Mathematical diffraction theory is concerned with the analysis of the diffraction image of a given structure and the corresponding inverse problem of structure determination. In recent years, the understanding of systems with continuous and mixed spectra has improved considerably. Simultaneously, their relevance has grown in practice as well. In this context, the phenomenon of homometry shows various unexpected new facets. This is particularly so for systems with stochastic components. After the introduction to the mathematical tools, we briefly discuss pure point spectra, based on the Poisson summation formula for lattice Dirac combs. This provides an elegant approach to the diffraction formulas of infinite crystals and quasicrystals. We continue by considering classic deterministic examples with singular or absolutely continuous diffraction spectra. In particular, we recall an isospectral family of structures with continuously varying entropy. We close with a summary of more recent results on the diffraction of dynamical systems of algebraic or stochastic origin.
Neutron powder diffraction study ( T = 4.2-300 K) and polarization analysis of YBaCuFeO5+δ

The crystal and magnetic structures of the perovskite YBaCuFeO5+δ have been studied in the temperature range T = 4.2-300 K by powder neutron diffraction. In addition to the antiferromagnetic ordering transition at TN = 442 K, a commensurate–incommensurate magnetic transition is detected at TN ′ = 190 K. Below this temperature, two sets of satellite peaks surround the (1/2,1/2,1/2) magnetic peak at d ∼ Å, collapsing into a single set of satellites below 155 K. Polarization analysis has been performed to confirm the magnetic nature of the (1/2,1/2,1/2)± satellites.
Examining the Effects of Theory of Mind on playing the Game of ’No Thanks!’ using ACT-R-based Cognitive Models

Theory of mind is the ability for an individual to reason about the mental state of themselves and others. This project studied the effects of theory of mind on playing the card game of No Thanks! using cognitive models. Multiple cognitive models using different orders of theory of mind were developed using instance-based decision making and a partial implementation of the cognitive architecture ACT-R. Additionally, the performance of these models against human players was examined. An iOS application was developed for the Apple iPad with which a user could play the game of No Thanks! against the developed cognitive models. Both an experiment with human subjects and simulations in which the models played one other were conducted. The results of both experiments showed that models using first-order or second-order theory of mind had a significant advantage over models using zero-order theory of mind. However, the advantage of using second-order theory of mind over first-order theory of mind appears to be not as substantial. Furthermore, this project demonstrated that an academic AI method like instance-based decision making is suitable for creating a competitive game AI for a competitive game.
Surfactant droplet evaporation and deposition patterns on waxy leaf surface

Leaf surfaces are often altered when attacked by various insects and diseases. To evaluate the effect of droplet deposition on pesticide application efficiency, evaporation and deposit pattern formation of single droplets deposited at various locations on waxy leaves were investigated under controlled conditions. The locations on leaves included the intervenial area, midrib and secondary vein on both adaxial and abaxial surfaces. Tests were conducted with 300 and 600 µm droplets containing water and a nonionic surfactant. The ambient temperature was 25oC and relative humidity was 60%. Evaporation time and wetted area of droplets varied with where droplets deposited on leaf surfaces. The difference in evaporation time of 300 µm droplets without the surfactant on the intervenial area, midrib and secondary vein of adaxial surface was 30% while the difference in wetted area was 39%. The wetted area was significantly larger on the adaxial surfaces than on the abaxial surface but the evaporation time between both surfaces was not significantly different. For the whole leaf, the average evaporation time of 300 µm droplets was decreased by 44% and the average wetted area was increased by 202% when 0.25% nonionic surfactant was added into the spray solution. The total mean evaporation time increased 279% and the total mean wetted area increased 166% without the surfactant, 452% and 229% with the surfactant when the droplet diameter was changed from 300 to 600 µm. The largest spread area of droplets was appeared on the midrib of adaxial surface with the surfactant. The 300 µm droplets had longer evaporation time per droplet volume and greater wetted area per droplet volume than the 600 µm droplets. Increased pesticide application efficiency could be achieved with smaller droplets containing the surfactant to enhance the droplet spreading at different positions on waxy leaves.
Improving the Continuum Dielectric Approach to Calculating pKas of Ionizable Groups in Proteins

The pH-dependent characteristics of a protein are determined by the pKas of its titratable residues. Continuum electrostatic approaches provide a fast means of calculating the pKas of the titratable residues in proteins immersed in aqueous ionic solution. Here, we show how optimization of the parameters used in continuum electrostatic calculations can lead to significant improvements in the accuracy of pKa predictions. Dependence on the protein dielectric constant is studied, and two classes of ionizable sites are identified: (1) a large number of mostly solvent exposed residues for which the best pKa is calculated if the protein dielectric constant is set close to that of the aqueous solvent; and (2) a small number of mostly buried residues for which the best pKa is calculated with a lower site-specific protein dielectric constant. These two classes of ionizable sites can be distinguished using a criterion based on desolvation energy. A priori determination of the optimum protein dielectric constant for.
Freestanding 3D graphene/cobalt sulfide composites for supercapacitors and hydrogen evolution reaction

The development of lightweight, flexible, electrochemically active materials with high efficiency is important for energy storage and conversion. In this study, we report the fabrication of a freestanding, 3-dimensional graphene/cobalt sulfide nanoflake (3DG/CoSx) composite for supercapacitors and hydrogen evolution catalysts. The graphene framework formed by chemical vapour deposition provides superlight, highly conductive electron transport pathways, as well as abundant pores for electrolyte penetration. The densely patterned cobalt sulfide nanoflake arrays grown by electrodeposition offer a large surface area for electrochemical reactions, high theoretical capacitance and efficient hydrogen evolution catalytic activity. As a proof-of-concept, supercapacitors made of the 3DG/CoSx composites deliver a high specific capacitance of 443 F g−1 at 1 A g−1, with excellent capacity retention of 86% after 5000 cycles and mechanical flexibility. In addition, the 3DS/CoSx composites show attractive features as hydrogen evolution catalysts, with a low overpotential of 0.11 V and a Tafel slope of 93 mV dec−1.
Picosecond Time-Resolved Raman Spectroscopy of Solids: Capabilities and Limitations for Fluorescence Rejection and the Influence of Diffuse Reflectance

It has been known for many years that it should be possible to discriminate between Raman and fluorescence phenomena on the basis of their differing temporal responses. However, it is only relatively recently that optical technology has advanced sufficiently to achieve the necessary combination of high repetition rate and picosecond laser pulses, coupled with “gateable” multichannel detectors with matched repetition rates and short on-times. Both electronic and optical gating technologies have been shown to significantly improve the Raman spectra of highly fluorescent solutions. However, the performance of such systems with solid materials has not been reported in detail. To partially redress this imbalance, this article describes the ps-time-resolved Raman spectroscopy of solid films and powders. Excellent temporal resolution and fluorescence rejection was obtained with homogeneous films, but with powders, multiple scattering has the potential to significantly blur the time resolution. For example, after incidence of a 1-ps pulse on a powdered sample of trans-stilbene, the Rayleigh signal was spread over 100 ps in time and the Raman signal persisted for more than 300 ps. Simple models are presented that predict these temporal responses on the assumption that photons randomly “diffuse” through the powder, scattering at particle boundaries and sometimes reemerging to be detected at a later time. These dynamics imply that fluorescence rejection with bulk powders might be less effective than with homogeneous solids as the broadened Raman signal would be incompletely captured within the short detector “on” period. The fluorescence would be rejected, but so would the Raman signal (to some extent), giving a poor signal-to-noise ratio. This long-term signal persistence could also complicate the interpretation of pump-probe spectroscopy studies. However, further work is needed to assess the practical implications of these findings.
Elastic Bending of Semiconductor Wafer Revisited and Comments on Stoney's Equation

Since Stoney derived a simple relationship between the stress of a thin film and the curvature of its substrate for an electrolytically deposited metallic film on a thick substrate plate in 1909, the equation has been widely used by electrochemists to calculate stresses in electrolytically deposited films. Although the equation seems to work well for thin films with negligible thickness in comparison to the substrate, the underlying assumption in his derivation is found to be questionable. Various works have been published which calculate more precisely the stresses in the bending of a two-layer composite plate, where a thin layer on a thick substrate is an extreme case. However, there is some confusion in differentiating elastic bending due to internal stress from the externally applied moments (including our previous work). We re-examine the two bending conditions and point out that Stoney's equation was derived based on a neutral axis for zero bending moment which does not exist in the pure bending of a steel ruler on which his derivation was based. We also show that a single neutral axis for stresses does not exist in a two-layer system bent by internal stresses. Finally, we rederive the formula for the relationship between the wafer curvature and the lattice mismatch or differential thermal expansion for a binary composite plate using the proper bending moment calculation and examine the case of wafer bending of GaAs on Si substrate.
New world record efficiency for Cu(In,Ga)Se2 thin‐film solar cells beyond 20%

In this contribution, we present a new certified world record efficiency of 20.1 and 20.3% for Cu(In,Ga)Se2 thin‐film solar cells. We analyse the characteristics of solar cells on such a performance level and demonstrate a high degree of reproducibility. Copyright © 2011 John Wiley & Sons, Ltd.
Natural radioactivity and associated radiation hazards of river sands in Xi'an, China

The natural radionuclide γ-ray activities and the gamma-absorbed dose rates, produced by 226Ra, 232Th and 40K were determined in sands collected from four big rivers in Xi'an, China, using γ -ray spectrometry. The activity concentrations of 226Ra, 232Th and 40K in sand samples ranges from 11.0 to 41.3 Bq kg−1, 16.3 to 52.3 Bq kg−1 and 618.5 to 1186.6 Bq kg−1, respectively. The concentrations of these radionuclides are compared with the typical world values and the average activity of Chinese soil and Shaanxi soil. Radium equivalent activities (Raeq), external hazard index (H ex) and representative level index (I γ r) are calculated for the samples to assess the radiation hazards arising due to the use of these sand samples in the construction of dwellings. All the sand samples have Raeq activity lower than the limit of 370 Bq kg−1, H ex less than unity and I γ r close to 1 Bq kg−1. The overall mean outdoor terrestrial gamma dose rate is 65.0 nGy h−1 and the corresponding outdoor annual effective dose is 0.080 mSv. None of the studied riverbeds are considered a radiological risk and sand can be safely used in construction.
Existence of Double-Charged Oxide Traps in Submicron MOSFET's

Channel resistance fluctuations in very small-area MOSFET's are caused by a localized modulation of the electrostatic potential at the channel region. The modulation is brought about by trapping and detrapping of the individual electrons into and from interface traps, respectively. The magnitude of the fluctuation is evaluated by using a screened Coulomb potential in two dimensional electron gas together with the electric image force. The magnitude of the channel current fluctuations increases with the number of trapped electrons. The RTS with three current levels is explained by the proposed “double-charged oxide trap” model.
Real time drift measurement for colloidal probe atomic force microscope: a visual sensing approach

Drift has long been an issue in atomic force microscope (AFM) systems and limits their ability to make long time period measurements. In this study, a new method is proposed to directly measure and compensate for the drift between AFM cantilevers and sample surfaces in AFM systems. This was achieved by simultaneously measuring z positions for beads at the end of an AFM colloidal probe and on sample surface through an off-focus image processing based visual sensing method. The working principle and system configuration are presented. Experiments were conducted to validate the real time drift measurement and compensation. The implication of the proposed method for regular AFM measurements is discussed. We believe that this technique provides a practical and efficient approach for AFM experiments requiring long time period measurement.
Facile upscaled synthesis of layered iron oxide nanosheets and their application in phosphate removal

Layered iron oxide nanosheet material is a new efficient adsorbent which is here developed and investigated for removing the eutrophicant phosphate from water. The layered Fe-III nanosheets are synthesized by anion exchanging layered Fe-II/Fe-III hydroxide chloride (green rust; GR) with dodecanoate, followed by solid state oxidation and exfoliation, by which the yield of the product can be easily scaled up. The obtained product exhibits a distinct platy structure with a minimal Fe-III oxide sheet thickness of 1 nm and lateral size of 100 to 200 nm as observed by means of high resolution transmission electronic microscopy, selected area electronic diffraction and atomic force microscopy. The Fe-III nanosheets can be well dispersed and stable in aqueous solution, showing a low tendency of aggregation. The performance of the obtained nanosheets to remove phosphate has been evaluated in kinetic and batch experiments under different environmental conditions (i.e. interfering anions and pH). The kinetic study shows that phosphate removal by the iron oxide quickly reaches a plateau with the rate constant k(2) ranging from 5.2 x 10(-4) to 1.4 x 10(-3) g (mu mol(-1) min(-1)) for the initial phosphate concentrations of 40 and 80 mu mol L-1 (1.2 to 2.4 mg P per L) at pH 7. The maximum phosphate adsorption capacity of the layered Fe-III nanosheets is 2540 mu mol g(-1) (about 77 mg g(-1); 4006 mu mol P per g Fe) at pH 5, showing excellent potential for phosphate removal from wastewater. Our results also indicate that the performance of the layered Fe-III nanosheets for phosphate removal is selective. X-ray photoelectron spectroscopic analyses of O 1s, Fe 2p and P 2p spectra provide evidence for phosphate removal by forming inner-sphere Fe-O-P surface complexes. The cost-effective, environmentally friendly and highly efficient layered Fe-III nanosheet material is a promising material for the removal of phosphate or other oxyanions in future water treatment technologies.
High-pressure high-temperature synthesis of Cr2O3 and Ga2O3

We report the results of high-pressure high-temperature (HP-HT) synthesis of two sesquioxides, Cr2O3 at 22 GPa and 1950°C and Ga2O3 at 21 GPa and 1600°C, and their X-ray diffraction and Raman studies. After HP-HT synthesis, both oxides presented assemblies of single crystallites that adopted a corundum structure. For HP-HT-synthesized single crystal of Cr2O3, we determined the lattice parameters and the atomic positions in the corundum structure as follows: a=4.9530 Å, c=13.5884 Å, Cr (12 c): 0, 0, 0.3475; O (18 c): 0.3058(5), 0, 0.25. We explained the ‘evidence’ for the existence of a ‘distorted’ corundum lattice above 13–15 GPa by resonant effects in Raman spectra. For Ga2O3, it was demonstrated that HP-HT synthesis can fully turn a sample from a monoclinic C2/m phase (β-Ga2O3) to a corundum phase (α-Ga2O3), although at ambient temperature this sluggish transition is usually completed at ∼35–40 GPa. It was found that α-Ga2O3 exhibits a very strong luminescence doublet that resembles the one in ruby, and hence could have potential for pressure calibration.
Cardiolipin content controls mitochondrial coupling and energetic efficiency in muscle

Decreasing mitochondrial energy-production efficiency in skeletal muscle can confer protection against diet-induced obesity. Unbalanced energy partitioning participates in the rise of obesity, a major public health concern in many countries. Increasing basal energy expenditure has been proposed as a strategy to fight obesity yet raises efficiency and safety concerns. Here, we show that mice deficient for a muscle-specific enzyme of very-long-chain fatty acid synthesis display increased basal energy expenditure and protection against high-fat diet–induced obesity. Mechanistically, muscle-specific modulation of the very-long-chain fatty acid pathway was associated with a reduced content of the inner mitochondrial membrane phospholipid cardiolipin and a blunted coupling efficiency between the respiratory chain and adenosine 5′-triphosphate (ATP) synthase, which was restored by cardiolipin enrichment. Our study reveals that selective increase of lipid oxidative capacities in skeletal muscle, through the cardiolipin-dependent lowering of mitochondrial ATP production, provides an effective option against obesity at the whole-body level.
Liquid-liquid phase separation of light-inducible transcription factors increases transcription activation in mammalian cells and mice

Engineering liquid-liquid phase separation into synthetic and optogenetic transcription factors increases gene expression. Light-inducible gene switches represent a key strategy for the precise manipulation of cellular events in fundamental and applied research. However, the performance of widely used gene switches is limited due to low tissue penetrance and possible phototoxicity of the light stimulus. To overcome these limitations, we engineer optogenetic synthetic transcription factors to undergo liquid-liquid phase separation in close spatial proximity to promoters. Phase separation of constitutive and optogenetic synthetic transcription factors was achieved by incorporation of intrinsically disordered regions. Supported by a quantitative mathematical model, we demonstrate that engineered transcription factor droplets form at target promoters and increase gene expression up to fivefold. This increase in performance was observed in multiple mammalian cells lines as well as in mice following in situ transfection. The results of this work suggest that the introduction of intrinsically disordered domains is a simple yet effective means to boost synthetic transcription factor activity.
Conformations and Metal Ion Affinities of Glutamine Binding with Alkali and Alkaline Earth Metal Cations: an ab initio Study

Conformations and reaction energetics are important for understanding the interactions between biomolecules and metal ions. In this work, we report a systematic ab initio study on the conformations and metal ion affinities of glutamine (Gln) binding with alkali and alkaline earth metal ions. An efficient and reliable method of searching low energy conformations of metalated Gln is proposed and applied to the complexes of Gln·M+/++ (M+/++=Li+, Na+, K+, Rb+, Cs+, Be++, Mg++, Ca++, Sr++, and Ba++). In addition to all conformers known in literatures, many new important conformations are located, demonstrating the power of the new method and the necessity of the conformational search performed here. The metal coordination modes, relative energies, dipole moments, and equilibrium distributions of all important conformations of Gln·M+/++ are calculated by the methods of B3LYP, BHandHLYP, and MP2. IR spectra and metalation enthalpies and free energies are also presented and compared with the available experiments.
Climate Change and Viticulture: Research Needs for Facing the Future

The rapidly increasing world population and the scarcity of suitable land for agricultural food production together with a changing climate will ultimately put pressure on grape producing areas for the use of land and the input of resources. For most grape producing areas the predicted developments in climate will be equivalent to becoming more marginal for quality production and/or will require improved resource management. This will have a pronounced impact on grapevine physiology, biochemistry and ultimately production methods. Research in the entire area of stress physiology, from the gene to the whole plant and vineyard level (including soils) will need to be expanded to aid in the mitigation of arising problems. Three major challenges can be identified: one related to the lack of knowledge about how plants, micro-organisms and pathogens will respond to a rise in CO2 concentration, temperature and a possible lack of water simultaneously under field conditions; the second related to evaluation of the carbon budget of vineyards and the release of nitrous oxide and possibly methane, two of the most potent greenhouse gases, from viticultural production systems and the development of mitigation strategies; and the third on the broader aspect of resource management in the production chain within the wine industry and possibilities for its improvement.
FitGISAXS: software package for modelling and analysis of GISAXS data using IGOR Pro

A software package for performing modelling and analysis of GISAXS (grazing-incidence small-angle X-ray scattering) data within the distorted-wave Born approximation has been developed using the IGOR Pro scripting language (http://www.wavemetrics.com). The tool suite uses a slab-model approach with the Abeles matrix method to calculate X-ray reflectivity curves, electric field intensity distributions and GISAXS intensities from supported or buried scatterers arranged in two or three dimensions in a stratified medium. Models are included to calculate the scattered intensity for monodisperse, polydisperse and interacting particles with various size distributions, form factors and structure factors. The source code for the entire package is freely available, allowing anyone to develop additional tools.