Miracle-dz/UniFAR-FTUs huggingface dataset:
Reactions of benzophenone in its triplet state with aliphatic substrates: hydrogen isotope exchange, formation of organochromium(III) species, and related reactions

U.V. irradiation (for up to 20 min) of benzophenone in 54%(v/v) dioxane–water in the presence of chromium(II) trifluoromethanesulphonate results in the formation of the penta-aquadioxanylchromium(III) complex. The complex is thought to arise from the trapping by CrII of dioxanyl radicals which are the result of H-atom abstraction by 3Ph2CO* from dioxane. On prolonged irradiation (1 h) in the presence of tracer quantities of tritiated water, the products are Cr(H2O)63+ and tritium-labelled dioxane, formed by reaction of the penta-aquadioxanylchromium(III) complex with hydronium ions present in the solution. When the irradiation of benzophenone and chromium(II) trifluoromethane-sulphonate is carried out in 54%(v/v) tetrahydrofuran–water and in 54%(v/v) 1,2-dimethoxyethane–water, the more acid-stable penta-aquachromium(III) complexes derived from tetrahydrofuran and 1,2-dimethoxyethane are formed.
Synthesis of Nanosized “Cored” Star Polymers

A synthetic approach to nanosized “cored” star polymers is reported. A 5,10,15,20-tetrakis(4-carboxyphenyl)porphyrin core was functionalized with four 2,2,6,6-tetramethylpiperidinyl-1-oxy (TEMPO) initiating groups. Four-armed star copolymers of styrene and 4-hydroxystyrene were synthesized and functionalized with 3,5-di(3-buten-1-oxy) benzyl bromide groups but exhibited poor solubility. As an alternative, 5,10,15,20-tetrakis(3‘,5‘-dihydroxyphenyl)porphyrin was functionalized with 2-bromo-2-methyl-propionyl groups capable of initiating atom transfer radical polymerization (ATRP). Copolymerization of the core initiator with 1-but-3-enyl-4-vinylbenzene and styrene at low conversion produced soluble eight-armed star block copolymers. Through the ring-closing metathesis (RCM) reaction, the alkene groups of the polymer were intramolecularly cross-linked. The ester groups linking the cross-linked polymer arms to the porphyrin core were hydrolyzed, producing a “cored” star polymer with a molecular weight of appro.
Efficient synthesis of β- and γ-amino acid derivatives using new functionalised zinc reagents: enhanced stability and reactivity of β-amido zinc reagents in dimethylformamide

The new zinc reagents 3 and 4 are not sufficiently stable to be prepared efficiently in THF, but they can be prepared in DMF under mild and convenient conditions; subsequent palladium- catalysed coupling with aromatic iodides gives protected β- and γ-amino acids 11 and 12 in generally good yields.
Efficiency of compost-fertilizer blends compared with fertilizer alone

Combining composts with sufficient fertilizer to meet crop requirements has several benefits over the use of compost as a sole N source, including reduced accumulation in soils of heavy metals, salts, or P. The objective of this research was to find blends of compost and fertilizer that would equal the yield and N uptake of N fertilizer. Biosolids compost-fertilizer blends made to equal 100 mg available N kg were compared with urea or NH4NO3 fertilizer. Zero to 50% of the blend's available N came from biosolids compost; the remainder came from fertilizer. N-labeled fertilizer was used to determine the proportion of N uptake attributed to fertilizer. Fescue (Festuca arundinacea Schreb.) was used as the indicator plant. Compost did not increase the efficiency of NH4NO3 fertilizer. The amount of available N provided by urea-compost blends was less than the amount provided by NH4NO3-compost blends. Urea-compost blends that had 17 to 50% fertilizer equivalents from compost equaled 100% urea. Blends of 50% NH4NO3 and 50% biosolids compost available N or 67% NH4NO3 and the equivalent of 33% biosolids compost N produced greater yields and N uptake by fescue. N analysis suggested that NH4NO3 fertilizer stimulated soil and/or compost mineralization producing more N than predicted from incubation studies of compost N mineralization rates. However, previous studies showed that soil mineralization was not affected by compost, which leads to the conclusion that fertilizer stimulated compost mineralization. Urea did not affect compost similarly, possibly because of a larger active N pool in urea compost blends compared with NH4NO3 compost blends.
Crystal structure solution of small‐to‐medium‐sized molecules at non‐atomic resolution

Data resolution limits the information carried by diffraction data and is therefore the most critical limit for the success of ab initio crystal structure solution. To overcome this limit, two methods have recently been proposed, namely the correction of resolution bias in electron-density maps and extrapolation of the structure factors beyond the data resolution limit. The first method has successfully been applied to powder data and the second to protein data. Neither of them has been applied to single-crystal data from small or medium-sized molecules. A third technique, the active use of the PSI-0 triplets in a tangent procedure, was applied to small molecules in the early days of crystallography, but it soon became obsolete because of the great success of methods combining reciprocal and direct space techniques. This paper explores the role of data resolution for small-to-medium-sized molecules and studies the usefulness of three auxiliary techniques, i.e. active use of the PSI-0 triplets, resolution bias correction and extrapolation of the structure factors.
Hall measurement studies and an electrical conduction model of tin oxide ultrafine particle films

The Hall effect has been measured for ultrafine particle films of tin oxide (particle size 50–200 A) in contact with reducing gases. Both the carrier concentration and mobility increased with an increasing concentration of reducing gas. As a result, conductivity, the product of the carrier concentration and mobility, shows a large gas concentration dependence. This means the ultrafine particle films are highly sensitive to gases. The variation of the carrier mobility with the gas concentration is interpreted in terms of a model in which the width of a long, thin channel, determined by particle size and Debye length, increases with a decrease in the number of O− ions desorbed by a chemical reaction with the reducing gases.
De l'importance de la fonction de poids dans le noyau des sous-arbres

Les methodes a noyaux sont une des approches permettant l’apprentissage a partir de donnees arborescentes. Parmi elles, nous nous interessons au noyau des sous- arbres, qui presente l’avantage combinatoire de pouvoir enumerer l’ensemble des objets utilises pour estimer la similitude entre deux arbres. Nous introduisons le concept de reduction DAG, puis de recompression DAG, qui menent a un algorithme efficace pour calculer le noyau. La possibilite d’aborder une base de donnees sous un format fortement compresse nous permet d’introduire une nouvelle fonction de poids, qui parvient a capturer de l’information dans des donnees ou les poids proposes dans la litterature n’y arrivent pas.
Enzyme-Catalyzed Ring-Opening Polymerization of Seven-Membered Ring Lactones Leading to Terminal-Functionalized and Triblock Polyesters

Terminal-functionalized polyesters and triblock polyesters were synthesized by lipase-CA-catalyzed ring-opening polymerization of seven-membered ring lactones, i.e., 1,5-dioxepan-2-one (DXO) and e-caprolactone (CL), in the bulk in the presence of an appropriate alcohol that acts as an initiator. To introduce a double bond at the chain end, 4-pentene-2-ol was used to initiate the polymerization of the lactones. The unsaturation introduced at the chain end in this way is a useful approach for synthesizing comb polymers. Two different dihydroxyl compounds, viz. poly(caprolactone diol) and poly(ethylene glycol), were used as macro-initiators. Triblock copolymers were synthesized in this way, where the macro-initiator formed the middle block. Polymers having different degrees of polymerization were synthesized by varying the molar feed ratio of monomer to initiator. DXO and CL showed significant differences in reactivity toward lipase-CA-catalyzed polymerization initiated by different alcohols as initiators. T.
Modeling of Cross-Flow Across an Electrostatically Charged Monolith Filter

The flow field and filtration efficiency of electrostatically charged micro-channel filters under cross-flow conditions were modeled. In our simulations, the fluid flows tangentially to the filter face (cross-flow). Particles with diameters larger than 2 μm were considered in this study, hence, the effects of Brownian motion were not included in the simulations. The influence of particle size, pressure drop, and electrostatic charge on the filtration efficiency was investigated. Measurements from performing electrostatic force microscopy (EFM) on the monolith sample confirmed the presence of charge and gave a qualitative measurement of the charge distribution. Results from the flow simulations indicate that the electrostatic forces increased the particle capture efficiency only at lower pressure drop. At higher pressure drops, electrostatic forces did not significantly increase the capture efficiency of the particles. Also, the capture efficiency of relatively small particles is found to be more dependent on the pressure drop across the filter than that of larger particles.
Tetrahydroisoquinoline‐Based N‐Oxides as Chiral Organocatalysts for the Asymmetric Allylation of Aldehydes

The short synthesis of a series of novel chiral N-oxideorganocatalysts and their evaluation in the asymmetric allylation reaction of aromatic and α-β-unsaturated aldehydes with allyltrichlorosilane is reported. These readily modifiable organocatalysts are the first of their kind based on the tetrahydroisoquinoline framework. The chiral homoallyl products were obtained with good chemical efficiency (up to 93 % yield) and high enantioselectivity (up to 91 % ee) under mild reaction conditions (23 °C).
Flow-Achieving Online Planning and Dispatching for Continuous Transportation With Autonomous Vehicles

In large-scale industrial applications, goods must be continuously transported between locations, which in the absence of conveyor systems is by a fleet of individual vehicles. This article introduces flow-achieving scheduling tree (FAST), an online dispatching algorithm that allows vehicles to efficiently operate as a team to maximize the system’s throughput while meeting a production schedule. A high-performance model is developed for high-fidelity prediction of vehicle interactions and system performance. It is subsequently optimized using a self-tuning variant of Monte Carlo tree search (MCTS) to make agile dispatch decisions in real time. The method is validated using an open-cut mine site and is shown to outperform a commonly used algorithm in this domain. Note to Practitioners—This article was motivated by the problem of dispatching autonomous haul trucks on open-cut mine sites. The proposed method is suited to any industrial transportation system where a continuous stream of goods must be efficiently transported between the load and unload stations by a potentially heterogeneous fleet of automated vehicles. The system makes decisions in real time while reacting to performance variations and disturbances by using a receding horizon approach. Off-the-shelf software commonly used in this domain is based on heuristics with limited ability to optimize, leading to myopic decision making without taking vehicle interactions into account. Here, flow-achieving scheduling tree (FAST) overcomes this by optimizing over possible schedules and thereby implicitly accounting for knock-on effects. Future work will incorporate additional constraints into the optimization process and validate FAST in other industrial domains.
Test-anxiety and achievement of B.ed student teachers

As a part of formative assessment B. Ed student teachers were supposed to have individual presentations of some elements/topics from their trimester course work. It was observed by the researcher that student-teachers feel anxiety before and during presentations. Once, when quite a good number of student-teachers were found absent in the class during the trimester, and when asked for, one of the student-teachers present in the class answered, “When it comes to presentations/test/examinations and now our examination is approaching fast, they feel like dying or committing suicide. ” To author, that was an enough sufficient indication of anxiety among the student-teachers studying at tertiary level. Hence it was decided by the authors to find out through this mini research the anxiety in these student-teachers. One self-made test anxiety inventory was administered to them and the observations and results have been recorded. It was evident from this work that student-teachers at tertiary level also face anxiety and related problems. It was also compared with the exam scores of the subjects. If they are, “Test-wise”, the anxiety and related problems would be minimal. So, they need to be, “Test-wise”.
A Calibration Technique for Improving Refractive Index Retrieval from Aerosol Cavity Ring-Down Spectroscopy

Cavity ring-down spectroscopy (CRDS) is a technique that is commonly used to measure the extinction of light by aerosol particles in situ. This extinction, when normalized to particle concentration, yields the extinction cross section, a measure of a single particle's ability to scatter and absorb light. The complex index of refraction can then be retrieved by comparison of the extinction cross sections at several particle diameters with those predicted by Mie theory. This approach requires accurate determination of particle diameter and concentration as well as the length of the extinction region in the cavity, but it is often difficult to quantify the systematic errors in the measurements of these quantities. Here, we introduce a calibration technique using particles of a reference compound to account for these systematic errors. The two calibration parameters are: Cf , which scales the measured extinction cross sections, and Δd, which shifts the particle diameters. It is found that Cf correlates strongly with the condensation particle counter (CPC) used to measure particle concentration and that Δd is associated with the differential mobility analyzer (DMA) used to select particle diameters. Calibration is shown to reduce errors of subsequently-measured extinction cross sections of a test aerosol from 11% to with a concomitant improvement in the accuracy of the retrieved complex index of refraction and corresponding atmospheric radiative forcing estimates. Copyright 2013 American Association for Aerosol Research
Determination of rotational viscosity of nematic liquid crystals from transient current : numerical analysis and experiment

A simple method is presented for the determination of the rotational viscosity of nematic liquid crystals. Theoretical expressions for the rotational viscosity from transient displacement current in nematic liquid crystals are derived. The validity of the expressions is numerically examined. It is found that the rotational viscosity can be obtained with sufficient accuracy. The rotational viscosity of ZLI-2293 (Merck Ltd.) is measured at various temperatures by the present method.
Sources and Source Strengths of Volatile Organic Compounds in a New Office Building

This study was conducted at a newly constructed federal office building in Portland, Oregon. The primary objectives were to identify the major sources of volatile organic compounds (VOC) in the building and to measure both long-term (one year) and short-term (several day) variations in concentrations and source strengths. Samples for VOC were collected on four occasions over a period of 14 months starting with the first month of occupancy. During the final sampling period, samples were collected over four days (Friday - Monday). The samples were analyzed for individual compounds and for total VOC (TVOC). The results were expressed as specific source strengths, as well as concentrations, to facilitate comparisons of measurements made under different ventilation conditions. The primary source of VOC in the building was identified as liquid-process photocopiers and plotters which emitted a characteristic mixture of C10-Cn isoparaffinic hydrocarbons. The specific source strength of TVOC, which was dominated b.
Nitrogen-doped hierarchically porous carbon as efficient oxygen reduction electrocatalysts in acid electrolyte

Nitrogen-doped carbon was found to exhibit excellent activity as an electrocatalyst in renewable energy devices. A controllable method to synthesize N-doped hierarchically porous carbons (PNCEs) partly with graphene-like structure using polyaniline (PANI)–polyvinylpyrrolidone (PVP) composite as a carbon source via a soft-template process was reported. The catalytic mechanism was thoroughly studied to better understand the relationship between the structure, Fe species and catalytic activity. The PNCE prepared at 1000 °C displays the best performance achieving a maximum power density of 456 mW cm−2 and oxygen reduction reaction (ORR) onset potential of 0.90 V. More prominently, the catalyst presents superior stability, as well as poison tolerance including methanol and SO2 to the commercial JM-Pt/C catalyst in 0.5 M H2SO4. The PVP is proven to tailor the structure, improve the surface area, and alter the transition metal species. The PNCEs synthesized under NH3 exhibit considerably better catalytic activity toward ORR compared with the undoped carbon and PNCEs synthesized under an N2 atmosphere. Furthermore, we find that the nitrogen bonding configurations, textural structure, Fe species and surface areas of PNCEs play key roles in the electrocatalytic activity towards the ORR. The formed FeN4 species hosted in the micropores acts as the active component for ORR activity in PNCEs, although it is not the only contributor to the high performance of PNCEs. The catalyst is expected to be a promising non-noble electrocatalyst for use in polymer electrolyte membrane fuel cells.
Proton inclusion properties of a new azamacrocycle. Synthesis, characterization and crystal structure of [H3L][Cl]3·2H2O (L = 4,10-dimethyl-1,4,7,10-tetraazabicyclo [5.5.2] tetradecane)

Abstract Macrocyclic compounds have been extensively investigated, the interest for this huge class of compounds spans from fundamental research to specific industrial applications. 1 – 8 We have recently published a few papers on small macrocycles having cage-like molecular topology.9 – 19 They present special proton-transfer properties and in few cases they are strong, selective lithium binders in aqueous solution.14,15,17 The three-dimensional cavity present in these compounds is achieved by connecting two secondary nitrogen atoms of a tetraazamacrocycle with different bridging groups (see Fig 1). Molecular topology and nature of donor atoms are the most important elements influencing the chemical properties of this class of compounds. For these reasons we are continuing our investigations on these compounds by systematically changing the bridging unit; we report here the synthesis and chemical properties of the new cage 4,10-dimethyl-1,4,7,10-tetraazabicyclo[5.5. 2]-tetradecane, abbreviated as L.
Direct patterning of noble metal nanostructures with a scanning tunneling microscope

We demonstrate in this article the controlled deposition of noble metal dots and lines using local chemical vapor deposition in the tip–sample gap of a scanning tunneling microscope. 3 nm diam rhodium dots have been patterned by local decomposition of an inorganic precursor, which was synthesized on purpose. Deposition is obtained on gold surfaces by applying a series of negative voltage pulses on the sample exceeding a voltage threshold of 1.9 V. The influence of kinetics parameters (pulse voltage duration and number, as well as the effect of gas pressure) are presented. In a second step, the deposition process has been applied on hydrogenated silicon (100) surfaces. These samples were previously hydrogen passivated using two different wet etching operations, leading surface dangling bonds saturated by either mono- or di-hydride bonds. The difference in the deposition processes observed in both cases is discussed.
A detailed investigation of the formation kinetics and layer structure of poly(ethylene glycol) tether supported lipid bilayers

Supported lipid bilayers formed from liposomes containing phospholipids with covalently attached poly(ethylene glycol) (PEG-SLBs) potentially circumvent two current limitations of membrane sensor platforms, namely air-stability and limited aqueous space between the sensor substrate and the membrane. However, questions regarding the formation kinetics through self assembly and the presence of a PEG cushion underneath the lipid bilayer are still unanswered. Quartz crystal microbalance with dissipation monitoring and fluorescence recovery after photobleaching (FRAP) measurements show that PEG-SLB formation through self-assembly is possible in the mushroom regime while it is hindered in the brush regime. The observed dependence of the kinetics on grafting density and molecular weight of the PEG-lipids is attributed to the electrostatic and steric shielding effect of the enveloping PEG layer. In the mushroom phase, non-densely packed PEG does not completely screen lipid-surface interactions while in the brush phase, densely packed non-interacting PEG chains stabilise liposomes and prevent overall attractive interactions. Force–distance measurements are used to directly measure the thickness of the PEG-SLB structure and demonstrate the presence of PEG chains on both sides of the lipid bilayer. FRAP measurements support this finding by showing increased lipid mobility for increased PEG layer thickness through decoupling of the membrane from the substrate. Force–distance and FRAP measurements further reveal the mobility of the PEG-lipids and the novel detailed behavior of laterally mobile PEG mushrooms under mechanical compression.
Essential Oil Content and Composition of Lavandula Angustifolia Mill. as Affected by Drying Method and Extraction Time

Abstract The aerial parts of Lavandula angustifolia Mill. , were collected from Iran at the full-flowering stage and dried by three different drying methods (sun-drying, shade-drying and oven-drying at 45°C). The essential oils were extracted by hydro-distillation method with two different times of extraction (1 and 3 hours) and analyzed using GC and GC/MS. Although extraction time has no significant effect on the essential oil composition, the drying methods yielded significant effects. Forty components were detected in the oil of L. angustifolia under different drying methods, including, 1,8-cineole (29.0-38.0 %), linalool (6.8-19.2 %), camphor (9.6-14.6 %), borneol (8.4-15.2 %) and β-phellandrene (4.0-7.0 %), as main components.
Contribution of SO3 to the acid neutralizing capacity of Andosols exposed to strong volcanogenic acid and SO2 deposition

Soil response to acid and sulphur inputs is influenced largely by the soil's physico‐chemical properties. We studied the effects of such depositions in two types of Andosols exposed to volcanogenic emission (Masaya, Nicaragua), namely Eutric Andosols rich in allophanic constituents, and Vitric Andosols rich in volcanic glass. Small mineral reserves and large contents of secondary short‐range ordered minerals indicate a more advanced weathering of the Eutric than the Vitric Andosols. Strong correlations between soil specific surface and oxalate‐extractable Al, Si and Fe contents highlight the predominant contribution of short‐range ordered minerals to surface area.