Miracle-dz/UniFAR-FTUs huggingface dataset:
Crystal structure and biodegradation of aliphatic polyester crystals

The biodegradability of aliphatic polyesters, which are produced by biosynthesis and chemo-synthesis, strongly correlates to the polymer morphology such as crystallinity, molecular orientation, chain packing and crystal surface, in addition to the chemical structure. For elucidation of biodegradation mechanism of crystal regions on an atomic level, lamellar single crystals of poly([R]-3-hydroxybutyrate) (P(3HB)) and its copolymers, poly([R]-3-hydroxyvalerate) (P(3HV)), poly(4-hydroxybutyrate) (P(4HB)), poly(L-lactic acid) (PLLA) and poly(ethylene succinate) (PES) were prepared from dilute solution by isothermal crystallization, and the crystal structures and morphologies were investigated by means of mainly transmission electron microscopy and atomic force microscopy. All single crystals were intramolecular single crystals, with spiral growth in some cases, and these crystals gave well-resolved electron diffractograms. The enzymatic degradation of lamellar crystals of P(3HB) and its copolymers was carried out with extracellular PHB depolymerases, and it was revealed that enzymatic degradation of lamellar crystals progressed from crystal edges and ends rather than the chain-folding surfaces of crystals, in spite of the homogeneous adsorption of enzyme molecules on the crystal surfaces by substrate-binding domain. Furthermore, in the case of PLLA single crystals, single crystals were also degraded from the edges to yield a rounded shape without decreasing the molecular weights and lamellar thickness. These results suggest that the attack by the active site of enzyme takes place at disordered regions of the crystals, that is, disordered lateral sites with high mobility of molecular chains are preferentially degraded.
A theoretical STM study of Co n /Pt(111)

It is shown that by ‘stacking’ together a semi-infinite sample subsystem with a semi-infinite tip subsystem, difficulties with respect to a common Fermi level for the whole system can approximately be overcome in all those cases when the substrate (serving as lead) and the second lead are different materials. Based on this procedure by means of the spin-polarized (fully) relativistic screened Korringa–Kohn–Rostocker method and an equivalent Kubo equation, theoretical spin-polarized STM spectra for Pt(111)/Co n /Cr15 W22/Cu(111) with respect to an applied external magnetic field are evaluated in terms of difference conductivities as a function of the corresponding free energy. These spectra are interpreted using layer-resolved contributions to the difference conductivities in order to indicate which parts of the sample dominate changes in the tunneling current caused by changing the orientation of the magnetization. Also shown are estimates of the time-scales to switch from perpendicular to in-plane and vice versa. All investigated properties suggest that different situations apply when the number of Co layers on top of Pt(111) is increased from one to three.
In‐situ Analysis of Lichen Pigments by Fourier Transform Laser Microprobe Mass Spectrometry with External Ion Source

Several selected lichen samples are analysed by Fourier transform laser microprobe mass spectrometry with 5 μm resolution and with virtually no sample preparation. The application area can be increased to molecules with molecular weight higher than 500, because of the detection of post-laser generated ions. In most cases, enough information is available to allow, in combination with IR and NMR data, complete structural characterization of the pigments, without the analysis of reference products.
Frequency-Dependent Switching Behavior under Triangular Waves in Antiferroelectric and Ferrielectric Chiral Smectic Phases

A realistic model structure of the ferrielectric phase is proposed by taking into account the apparent tilt angle measurements. On the basis of the model, the electric and optical responses are investigated in the ferrielectric SmCγ* as well as in the antiferroelectric SmCA* phases of MHPOBC (C8H17O---COO--COOC*H(CH3)C6H13) under triangular waves of various frequencies. At low frequencies, D-E curves show double and triple hysteresis loops characteristic of the antiferroelectric and the ferrielectric phases, respectively. T (transmittance)-E curves also reveal similar hysteresis loops. With increasing frequency, the direct switching between the two ferroelectric states occurs without passing through the antiferroelectric state or the ferrielectric states. The complicated frequency dependence is interpreted based on the spatially inhomogeneous domain switching.
Coarse-grained interactions in polymer melts: a variational approach

We investigate the modeling of a polymer melt on large length scale by averaging out fast fluctuating degrees of freedom in the microscopic model. We determine pair interactions in the coarse-grained system that give the best representation of the fine-grained system in a variational sense. Starting from the Gibbs-Bogoliubov inequality we derive a correction to a trial potential that minimizes the variational free energy of the coarse-grained system. By applying this correction repeatedly, pair interactions that are optimal in variational sense are obtained self-consistently. To calculate the potential of mean force in the polymer system, we consult the replica approach. The effective potential results in a radial distribution function for the coarse-grained sites that is less structured than that of the microscopic system. We also found that the soft effective interaction is unable to reproduce the virial distribution of the fine-grained system.
Characterization of Nitrate Contamination in an Arid Region of China

There are two pathways for nitrate to enter into human body: drinking water and food. Therefore, nitrate contamination of drinking water and agricultural crops is of particular interest to governments and the general public owing to the possible implications for health. This work investigated nitrate contents in various crops and in different parts of each crop and in drinking water as well in the Zhangye Basin, Northwest China. It provided evidence of severe nitrate contamination of drinking water, especially, in vegetable-growing villages. As to the nitrate contamination of crops, the present study revealed that all sampled crops adjust their nitrate distributions in a way that the edible parts contain much less nitrate than non-edible parts except lettuce. The nitrate content in the edible root of lettuce reached up to 5900 mg/kg exceeding the limit set by the European Commission.
Supply chain risk analysis of company X : risk management tool for supply chain risks

Purpose – The purpose of this research is to develop a supply chain risk management tool that can measure/assess and monitor risk in the supply chain. Additionally, this research redesign assessment and monitoring models for the automotive company in the Netherlands. Design/methodology/approach – This business research uses multiple methodologies to solve the business problem for company X. First, the problem solving methodology of Aken et al. (2012) was used during the process. The supply chain-risk literature is then further analysed and several interviews in combination with the business documentation are used for identifying the SC risks, with the aim developing a risk management tool. Findings –The risk management tool is constructed based on a probability–impact matrix and a multi-criteria scoring procedure. This risk management tool calculates the risk degree of each identified risk and monitors these risks over time with weights. The risk management tool is a visual construct so it is easy to understand under which risk level the company operates. Research limitations/implications – This research has some limitations. One issue was time limitation; this results in that the research focused only on main supply chain risks with disruptive potential. Practical implications – The risk management tool was constructed especially for company X to measure its supply chain risk. There is a possibility to introduce this model to other industries if the risk identification and risk categories match a company’s requirements. Originality/value – This research redesign two methods to assess and monitor risks in the supply chain and implement the risk results in a colour visual manner. Key words- Supply chain risk management, Supply chain risk, Risk management process, Risk assessment, Risk management, Automotive industry
Extraction of Lanthanides with Diamides of Dipicolinic Acid from Nitric Acid Solutions. I

Abstract Three ortho-, meta-, and para-derivates of ethyl(tolyl)diamides of dipicolinic acid were synthesized and tested on their extraction performance from nitric acids solutions. Extraction of americium and lanthanides (Ln) by these compounds as a function of nitric acid concentration was studied. Distribution ratios of studied metals were determined using ICP-OES method and radiotracer 241Am. Am/Ln separation differs among studied diamides, and the best separation was found for N,N′-diethyl-N,N′-di(ortho)tolyl-diamide.
Regeneration of used engine lubricating oil by solvent extraction

Abstract Huge amounts of used lubricating oils from automotive sources are disposed of as a harmful waste into the environment. For this reason, means to recover and reuse these wastes need to be found. Problems arising from acid treatment include environmental problems associated with the disposal of acid sludge and spent earth, low product yield (45-65%) and incomplete removal of metals. The processes of re-refining of used lubricating oils depend greatly on the nature of the oil base stock and on the nature and amount of contaminants in the lubricant resulting from operations. The study was carried out on a sample of 15W40 type used oil collected from one automobile. The re-refining process of used oil consists of dehydration, solvent extraction, solvent stripping and vacuum distillation. This study aims to investigate a process of solvent extraction of an alcohol-ketone mixture as a pre-treatment step followed by vacuum distillation at 5 mmHg. The primary step was conducted before the solvent extraction that involves dehydration to remove the water and fuel contaminants from the used oil by vacuum distillation. The solvent extraction and vacuum distillation steps were used to remove higher molecular weight contaminants. The investigated solvent to oil ratios were 2, 3, 4, 5 and 6. The solvent composition is 25% 2-propanol, 50% 1- butanol and 25% butanone or methyl ethyl ketone (MEK). The percentage of oil recovery for the solvent to oil ratio of 6:1 is further improved, but for the ratio values higher than 6:1, operation was considered economically not feasible. Finally, the re-refined oil properties were compared with the commercial virgin lubricating oil properties.
Synthesis and characterization of mesoporous CaO–MO–SiO2–P2O5 (M = Mg, Zn, Cu) bioactive glasses/composites

Mesoporous CaO–MO–SiO2–P2O5 (M = Mg, Zn, Cu) bioactive glasses/composites have been prepared by a one-pot synthesis route of simultaneous evaporation-induced self-assembly of Ca, P, Si and M sources. The effects of the substitution of CaO by MO in the mesoporous bioactive glasses/composites on the mesoporous structure and hydroxyapatite (HA)-forming ability were studied. The amorphous silicate can be detected on all the mesoporous CaO–MO–SiO2–P2O5 (M = Mg, Zn, Cu) bioactive glasses/composites, and Zn2SiO4 and CuO can be clearly detected on bioactive glass with high Zn contents and all of the Cu-containing bioactive glasses/composites, respectively. The MgO-substituted bioactive glasses/composites show the highest surface area among all MO-containing glasses/composites and the presence of crystallized phases of Zn2SiO4 and CuO in the ZnO- and CuO-containing bioactive glasses/composites lead to the decreased surface area and pore volume. The substitution of Ca with Mg, Zn or Cu inhibits the formation of HA deposition on the surface of the mesoporous bioactive glasses/composites, especially at high MO contents. The presence of MgO, ZnO and CuO slowed down the deposition rate of HA following a sequence of Cu < Mg < Zn. Therefore, the HA crystallite size and morphology can be easily tuned by the incorporation of Mg, Zn and Cu, which facilitates the wide application of the mesoporous bioactive glasses/composites.
EFFECT OF NITROGEN SOURCES AND RATES ON YIELD AND QUALITY OF SILAGE CORN

The objective of this study was to determine the effect of nitrogen (N) application source and rate on silage corn (Zea mays L.). Urea, ammonium nitrate, and ammonium sulfate were compared at 50, 100, 150, and 200 kg N ha−1. The application of ammonium sulfate produced the highest plant height, leaf area index (LAI), total yield, and stem, leaf, and ear dry matter, followed by ammonium nitrate and urea. However, nitrogen sources had no marked effects on the content of protein, ash, oil, soluble carbohydrates, acid detergent fiber (ADF) and neutral detergent fiber (NDF). As the rate of nitrogen increased plant height, LAI, total yield, and stem, leaf, tassel, and ear dry matters, and protein, ash and oil contents increased while soluble carbohydrates, ADF, and NDF contents decreased. Ammonium sulfate was the most effective N source on production and 200 kg N ha−1 was the most effective N rate on corn yield and quality.
Tracing interactions in the indigenous Caribbean through a biographical approach : Microwear and material culture across the historical divide (AD 1200-1600)

Much attention has been paid to the exchange of objects, ideas, and people in the Caribbean. Networks of interaction connected local communities across pan-regional scales, shaping indigenous socio-political integrations and their responses in colonial situations. This work examines the poorly understood cultural trajectories and reinterpretations of celts and paraphernalia exchanged in the late pre-colonial and early colonial Dominican Republic and the Windward Islands. Reconstructing the biographies of these artefacts traces their ‘object life’ sequences from start to finish. The dissertation principally applies microscopic wear trace analysis supported by experimental archaeology to examine the manufacturing technology and use of the studied objects. Integrated with contextual analysis and provenance data, the reconstructed biographies form a window into cross-cultural patterns of artefact production, function, and circulation. These are interpreted following a relational perspective adopted from Amerindian ontologies. The exchange of ground stone celts is shown to be closely interrelated with regional network structures. Though only specific communities specialised in production activities, requisite technical knowledge was widely shared. Once acquired, even exotic rocks and tool types were polished, hafted, and used in conventional ways. Conversely, the cultural and social values of most carved shell and bone paraphernalia are foremost expressed in local technological traditions and the preservation of inherited practices. These findings produce a better understanding of indigenous material culture and its relation to social interactions in the pre- and early colonial Caribbean.
A novel multiple linear multivariate NIR calibration model‐based strategy for in‐line monitoring of continuous mixing

The capability of near infra-red (NIR) spectroscopy to predict many different variables, such as concentration and humidity, has been demonstrated in many published works. Several of those articles have been in the subject of real time prediction of continuous operations. However, those demonstrations have been for narrow ranges of the variables, especially for powder concentration, which could present a nonlinear behavior of the NIR absorbance as a function of the entire range of concentration. This work developed a novel strategy to predict the entire range of powder concentration using multiple linear NIR calibration models. The root mean standard error of prediction and relative standard deviation (RSD) parameters were used to establish the number of the multiple linear calibration models; other statistical features were used to establish the correct prediction. It was found that a minimum number of linear partial least squares (PLS) calibration models were necessary to accurately predict the range from 0 to 100% w/w. This technique could also be used with other nonlinear behaviors. V C 2014 American Institute of Chemical Engineers AIChE J, 60: 3123–3132, 2014
New ladder‐type conjugated polymer with broad absorption, high thermal stability, and low band gap

New ladder-type π-conjugated polymer poly{6-alkyl-pyrrolo[3,2-b:4,5-b′]bis-[1,4]benzothiazine} (PPBBTZ) was synthesized through a simple method. PPBBTZ showed good solubility in organic solvents (such as chloroform, tetrahydrofuran, chlorobenzene, o-dichlorobenzene) and high thermal stability (decomposition temperatures up to 323 °C and 299 °C in nitrogen and air, respectively). The highest occupied molecular orbital and lowest unoccupied molecular orbital energy level estimated from electrochemistry result and absorption spectrum were −5.46 and −3.81 eV, respectively, with a band gap of 1.65 eV. More interestingly, PPBBTZ displayed broad absorption from ultraviolet to visible light regions (200–750 nm). These properties suggested PPBBTZ was a good candidate in opto-electronics. © 2012 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2012
Initiation and propagation thresholds of positive prebreakdown phenomena in hydrocarbon liquids

This paper presents an experimental study of the initiation of positive streamers under step voltage in point-plane geometry, in a number of hydrocarbon liquids. The experimental conditions (point tip radius, pulse risetime, gap length) were strictly controlled in order to take valid measurements of the initiation fields and threshold propagation voltages of streamers. Transient currents associated with the initiation of positive streamers were recorded down to the /spl mu/A range with a sensitive differential measurement technique. The different current shapes obtained in the liquids studied are presented. The measured inception fields of positive streamers and propagation thresholds of filamentary streamers are discussed according to the properties of the liquids (ionization potentials and mobility of charge carriers). >
Molecular Docking Simulation of Short-Chain Four Disulphide Bridged Scorpion Toxins with Structural Model of Human Voltage-Gated Potassium Ion Channel Kv1.3

We report structural model of the human voltage-gated potassium ion channel Kv1.3 obtained based on the crystallographic structure of KcsA by homology modeling. Molecular docking simulations were performed between the model structure of Kv1.3 channel with three short-chain four disulphide bridged scorpion toxins HsTX1 from the venom of Heterometrus spinnifer (Scorpionidae), maurotoxin (MTX) from Scorpiomaurus palmatus and Pandinus toxin 1(Pi1) from Pandinus imperator which belongs to the � -KTx6 subfamily. By integrating the homology modeling and docking simulations we obtained the three dimensional structures of toxin-channel complexes. The final docked complexes were then subject to minimization with CHARMM force field and investigated key interacting residues, electrostatic interaction energies, binding free energies, disulphide bridge pairing determination, folding pattern, hydrogen bond formation, hydrophobic contacts and flexibilities between selected scorpion toxins to the Kv1.3 channel.
Free Energy of a Nonuniform System. I. Interfacial Free Energy

It is shown that the free energy of a volume V of an isotropic system of nonuniform composition or density is given by : NV∫V [f 0(c)+κ(▿c)2]dV, where NV is the number of molecules per unit volume, ▿c the composition or density gradient, f 0 the free energy per molecule of a homogeneous system, and κ a parameter which, in general, may be dependent on c and temperature, but for a regular solution is a constant which can be evaluated. This expression is used to determine the properties of a flat interface between two coexisting phases. In particular, we find that the thickness of the interface increases with increasing temperature and becomes infinite at the critical temperature Tc , and that at a temperature T just below Tc the interfacial free energy σ is proportional to (T c −T) 3 2 . The predicted interfacial free energy and its temperature dependence are found to be in agreement with existing experimental data. The possibility of using optical measurements of the interface thickness to provide an additional check of our treatment is briefly discussed.
Large-scale synthesis of Co2V2O7 hexagonal microplatelets under ambient conditions for highly reversible lithium storage

Micro-/nanostructured mixed transition metal oxides (MTMOs) with their unique morphologies have attracted much attention due to their potential applications such as lithium-ion batteries (LIBs). Nevertheless, in contrast to active research for the synthesis of MTMOs (AxB3−xO4 (A, B = Co, Ni, Zn, Mn, Fe)), metal vanadates seem to be an unnoticed group, possibly due to the lack of appropriate synthetic methods. In this work, for the first time, we report a structure- and size-controlled synthesis of pseudohexagonal monoclinic Co2V2O7·nH2O monodisperse hexagonal nanoplatelets (MHNPs) through a facile water bath method via a micelle-assisted assembly-Ostwald ripening process. The amount of hexamethylenetetramine in the reaction was found to be pivotal to the formation of hexagonal nanoplatelets. Additionally, the structure of MHNPs could be retained only in a certain temperature range. By calcination of Co2V2O7·nH2O in air, mesoporous Co2V2O7 MHNPs composed of numerous nanometer-sized subunits could be harvested. Benefiting from the unique structure and probably synergetic effects of different metal ions, the as-prepared Co2V2O7 MHNPs possess high specific capacity, long-term cycling stability, and good rate capability. Specifically, the Co2V2O7 MHNPs exhibit a reversible capacity as high as 866 mA h g−1 with nearly 100% capacity retention after 150 cycles, making them potential electrode materials for LIBs.
Hydrogen bonding and molecular mobility in liquid water in external electromagnetic fields

Nonequilibrium molecular dynamics simulations of water have been performed in the isothermal–isobaric ensemble in the presence of external electromagnetic fields of varying intensity in the microwave to far-infrared frequency range, using a rigid/polarizable and a flexible/nonpolarizable potential model, from 260 to 400 K. Significant alterations in molecular mobility and hydrogen bonding patterns were found vis-a-vis zero-field conditions. In addition, the influence of the isothermal–isobaric ensemble on these observations was gauged by means of comparison with pure Newtonian simulation findings in the presence of external fields, and the former results were in reasonable accord with the latter.
One-step synthesis, growth mechanism and photoluminescence properties of hollow GeO2 walnuts

Hollow GeO2 walnuts were synthesized via a simple one-step process in an emulsion system. We investigated the growth mechanism and optical properties of the products and found that the reactive temperature and the addition of ethanol were crucial factors in controlling the morphology of GeO2 crystals. Above the ethanol boiling temperature, hollow walnuts were formed, whereas well-dispersed solid GeO2 polyhedrons and dimers were obtained below the critical point. A possible formation mechanism of the hollow interior of GeO2 walnuts is proposed suggesting that it was formed from the gas bubble released by the boiling ethanol and followed by the Ostwald ripening process of the encapsulating crystals. Photoluminescence measurement shows an enhanced emission peak at 538 nm for hollow GeO2 walnuts with blue shift compared with that of the solid structure. Our results indicate hollow GeO2 walnuts may have potential applications in light-emitting nanodevices. This method also suggests a new approach for fabricating other particles with hollow structure.