Miracle-dz/UniFAR-FTUs huggingface dataset:
The Radiationless Transfer of Energy of Electronic Excitation between Impurity Molecules in Crystals

The theory of transfer of electronic excitation energy between impurity molecules is developed without employing perturbation theory. The role of the lattice vibrations in the transfer process of the electronic excitation energy is taken into account. It is shown that the transfer time of electronic dipole excitation is proportional to the distance between molecules raised to the third power rather than to the sixth as it follows from the first-order perturbation theory. A connection of parameters determining the transfer process of electronic excitation with the spectra of impurity absorption and luminescence is found.
Unterrichtsbezogene Vorstellungen von Lehramtsstudierenden der Chemie am Beginn ihres Studiums und ihre Einordnung

Diese Studie uber unterrichtsbezogene Vorstellungen von Lehramtsstudierenden der Chemie am Beginn ihres Studiums basiert auf der Analyse von Zeichnungen, in denen Studierende sich selbst als Lehrperson in einer fur sie typischen Unterrichtssituation zeichnen und die dargestellten Aktivitaten und Ziele der Unterrichtssituation beschreiben. Das zu Grunde liegende Instrument und ein auf der Basis von Gegenstandsbezogener Theoriebildung (Grounded Theory) entwickeltes Auswertungsraster werden vorgestellt. Es werden ein Uberblick uber die Vorstellungen von 85 Lehramtsstudierenden der Chemie und eine Einordnung in den Zusammenhang von ahnlich grosen Studierendengruppen der Physik, Biologie und des Sachunterrichts gegeben. Die Ergebnisse zeigen, dass die Studierenden der Chemie im Vergleich zu Biologie und Sachunterricht starker lehrerzentrierte und sachstrukturorientierte Vorstellungen von Unterricht mit in ihr Studium bringen. Diese Auspragung ist allerdings nicht so stark entwickelt, wie in der Physik. Konsequenzen fur die Lehrerbildung werden diskutiert.
Development of Organic Fertilizer Products and Systems to Improve Soil Fertility of Organic Vegetable Production of Cabbage in Benguet, Philippines

Formulation of organic fertilizers were studied to support organic vegetable production in Benguet, Philippines. The formulated liquid organic fertilizers based on farmers’ concoctions showed very low nutrient contents. New formulations using legume seeds were done which resulted to higher nutrient contents. Likewise, solid organic fertilizers were formulated using locally available raw materials. A combination of 50% chicken manure, 20% sawdust, 20% sunflower leaves, 10% Alnus compost and Trichoderma gave the highest nutrient contents. The solid and reformulated organic liquid fertilizers and Trichoderma were tested on cabbage grown in farm under conversion to organic production. Lower yields were observed during the early part of conversion. However, after three years of conversion, the yields of cabbage had significantly increased which were comparable to the yield in conventional farms. The recommended rates of solid and liquid formulated organic fertilizers found effective for both cabbage are 10t/ha of formulated solid fertilizer and 60 ml/L of liquid fertilizer, respectively. The nutrient management system found effective for organic production of cabbage was the application of Trichoderma two weeks before planting and split application of solid organic fertilizers three times during the growing period, that is, before planting, 15 days after planting and 30 days after planting at the rate of 2.5, 2.5 and 5.0 t/ha, respectively. The organic liquid fertilizer was applied at the rate of 60 ml per liter of water 15 days after planting and every two weeks thereafter until cabbage heads have formed. This nutrient management system provided the crops the essential nutrients during the critical growth and reproductive stages which resulted to higher yields comparable to those produced in conventional farms.
Synthesis and Evaluation as Glycosidase Inhibitors of Carbasugar‐Derived Spirodiaziridines, Spirodiazirines, and Spiroaziridines

The spirodiaziridines 6 and 9, potential inhibitors of α- and β-glucosidases, were prepared from the validoxylamine A-derived cyclohexanone 5. The trimethylsilyl protecting groups of 5 are crucial for the formation of 6 in good yields. Oxidation of 6 gave 7. The diaziridine 6 (pKHA=2.6) and the diazirine 7 did not inhibit the β-glucosidases from almonds, the β-glucosidase from Caldocellum saccharolyticum, and the α-glucosidase from yeast. The N-benzyl diaziridine 9 is a very weak inhibitor of the α-glucosidase, but did not inhibit the β-glucosidases. To see whether the weak inhibition is due to the low basicity of the diaziridines or to geometric factors, we prepared the spiro-aziridines 21 and 25 and 1-epivalidamine (32). The known cyclohexanone 10 was methylenated and epoxidised to 16 and 17. Azide opening of 16 and 17, mesylation, LiAlH4 reduction, and deprotection gave the aziridines 21 and 25 respectively. 1-Epivalidamine (32) was prepared from the known carba-glucose 29. The aziridine 25 (pKHA=6.8) is a weak irreversible inhibitor of the β-glucosidase from Caldocellum saccharolyticum and a weak reversible inhibitor of the α-glucosidase from yeast, but did not inhibit the β-glucosidases from almonds. The poorly stable aziridine 21 weakly inhibited the three enzymes. Similarly, 1-epivalidamine (pKHA=8.4) proved only a weak inhibitor. The known cyclopentylamine 34 (pKHA=7.9), however, is a micromolar inhibitor of these enzymes. The much stronger inhibition by 34 is related to the pseudoaxial orientation of its amino group.
Surface-enhanced and STM-tip-enhanced Raman spectroscopy at metal surfaces

The strong electromagnetic field enhancement, occurring at illuminated metal structures with sub-wavelength dimensions, is exploited to develop Raman spectroscopy with exceedingly high sensitivity and lateral resolution, possibly down to single molecule detection. After reviewing Surface Enhanced Raman Spectroscopy (SERS) on single crystalline surfaces and colloids we present recent results on the Tip Enhanced Raman Spectroscopy (TERS) approach, where a metal tip is used as an external enhancing unit. In this way the electromagnetic and chemical surface enhancement are physically separated: the former is confined to the tip, the latter to the metal-adsorbate system. So far, TERS has been reported only for a few molecules exhibiting large Raman cross sections, such as sulphur or dye molecules. Here, we present combined SERS and TERS studies for the CN- ions and TERS for Brilliant Cresyl Blue adsorbed at smooth thin gold films.
Coping Strategies Used By Students with Disabilities in Managing Social and Higher Educational Experiences

: This study attempts to understand social and educational experiences of students with disabilities in institutions of higher education and is exploratory in nature. To understand the educational experiences of these students, it is not enough to know only the availability of services and resources. It is also necessary to understand the students personally, and the circumstances in which they live. To answer the research questions posed in this study, the researcher has used mixed methods and three universities were selected through purposive sampling in so as to gain maximum diverse variation. For this study, in-depth interviews were conducted with hundred students with disabilities in selected universities in Andhra Pradesh, India. In this study, quantitative and qualitative data analyses were used and in most cases quotes of real text for each theme were maintained and used extensively. The findings of the study show the students were very categorical about their special needs in order to achieve their goals. A greater understanding has been gained regarding coping strategies adopted by them to manage their higher education needs. Based on findings of the study the researcher has brought out the factors which influence the creation of an inclusive environment in institutions of higher education.
Tetrakis(triethylammonium) hexakis(isothiocyanato-N)nickel(II)

The unit cell of the title compound, (C 6 H 16 N) 4 [Ni-(NCS) 6 ], contains two independent centrosymmetric [Ni(NCS) 6 ] 4- anions and eight Et 3 NH + cations. The Ni-N distances are in the range 2.072 (4)-2.097 (4)A. In one anion, all six S atoms are hydrogen bonded to cations, but the second anion is involved in only two hydrogen bonds. There are no significant geometrical differences between the two anions.
Impact of Substrate Defects on the Equilibrium One-Dimensional Island Size Distribution

As long as only first-neighbour interactions are considered, equilibrium island size distributions of monoatomic islands in one dimension follow an exponential law regardless of the strength and the repulsive or attractive character of the adsorbate–adsorbate interactions. However, one-dimensional atomic wires obtained via nucleation at the step edges have a monomodal island size distribution. In this paper, we present a simple one-dimensional Monte Carlo model that shows how the monomodal distribution observed experimentally can be obtained by including surface defects that only suppress the interaction between two successive adsorbates.
Assessment of β-Carotene Content in Sweetpotato Breeding Lines in Relation to Dietary Requirements

Abstract Sweetpotato (Ipomoea batatas, Lam.) β-carotene represents an important nutritional source of vitamin A in a number of areas worldwide. Genetic variation for β-carotene and the minimum content required among cultivars for different levels of consumption were determined using a cross-section of the sweetpotato germ plasm. β-Carotene was separated and measured by HPLC using a Vydac C18 218TP54 column and a mobile phase of methanol:acetonitrile:tetrahydrofuran (25:28:2). Peak identity was established by spectral comparison using a Shimadzu SPD-M6A photodiode array UV-VIS detector. Recovery was determined by standard addition prior to saponification. Many of the white to pale cultivars did not contain any detectible provitamin A activity (β-cryptoxanthin, α-carotene, β-carotene). β-Carotene levels ranged from 1 to 190 μg · g−1 dry wt in blanched roots containing detectable levels of β-carotene. β-Carotene content was highly correlated with hue angle in lines with yellow to deep orange color (r = −0.99) and the relationship can be used for the estimation of β-carotene. The specific β-carotene content needed for new cultivars to provide the vitamin A requirement was estimated using the per capita consumption of sweetpotatoes in various geographic areas and the percentage of the RDA to be provided by sweetpotatoes. Populations in many areas of the world would benefit from increased β-carotene contents in available sweetpotatoes.
Simulation and experimental study of polymer deformation in nanoimprint lithography

A polymer deformation process is studied by numerical simulations and the results are compared with the related experimental results in nanoimprint lithography. The imprint pressures required for successful imprinting and the filling rate into the mold grooves are studied as the aspect ratio of the pattern, initial thickness of the polymer, and the duty ratio of the pattern are changed. The required pressure increases not only for high aspect ratio pattern but also low aspect ratio pattern. Also, the pressure increases when the initial thickness of the polymer decreases to less than about two times that of the groove depth of the mold. These results are explained by the deformation mechanism of the polymer and agree well with the related experimental results. Based on these theoretical and experimental studies, fabrication of a high aspect ratio pattern having 100 nm width and 860 nm height is successfully demonstrated using thick polymer by nanoimprint lithography.
Dispersion of collective excitations of amorphous and liquid Zr67Ni33 alloys

Molecular dynamics simulations have been performed to study the collective excitation of Zr67Ni33 amorphous and liquid alloys with a pair functional potential. The spectrum and the correlation function of the particle current are calculated for longitudinal and transverse modes. The dispersion relation is estimated from the spectrum. It is related to the peak position of the static structure factor and is strongly dependent on temperature at large wavenumbers. The collective excitation is evident for the Zr-Zr correlation but not for the Ni-Ni correlation. The motion of the Zr-Zr correlation is non-localized but that of the Ni-Ni correlation is localized. The sound velocity and the Debye temperature are calculated from the dispersion relation. The calculated power spectrum agrees with the previously reported experimental result. The power spectrum of the Zr atom of the amorphous state is similar to that of the crystal state. On the other hand, the power spectrum of Ni shows an obvious difference between the amorphous and crystal states.
Grain-size analysis and Arcellinida as tools for inferring paleoclimatological variability: a case study from Holocene Canadian Subarctic Lake Sediments

The central Northwest Territories of the Canadian Subarctic, and the myriad of lakes found therein, has through previous research been shown to archive records of past Holocene climate variability. Due to the low temporal resolution of previous paleoclimatic reconstructions questions remain as to past rates of natural climate change, a deficiency of concern to policy makers and modelers responsible with addressing human induced climate change. Two paleolimnological proxies of climate variability, end-member mixing analysis (EMMA) of lake grain-size distributions and the Arcellinida were further developed to increase the temporal resolution of paleoclimate reconstructions and provide a more complete picture of environmental response to past climate variability. A mm-interval subsampling strategy made possible through use of a custom-designed sledge microtome combined with EMMA of lake sediment cores significantly increased the temporal resolution of paleoclimate reconstructions. EMMA of lake sediment cores was used to describe changes in lake catchment hydrology and track the rate of climate deterioration and subsequent amelioration associated with known Holocene events such as the Holocene Climate Optimum (HCO) and the onset of the Neoglacial. Arcellinida as demonstrated here, are sensitive to treeline dynamics. Due to their well-preserved dissolution-resistant tests, rapid generation time and trophic position within lacustrine environments they offer unique insight into climate variability and change. Arcellinida are also characterized by ecophenotypes, which respond markedly to changing environmental conditions making them valuable tools for reconstructing environmental change. Three ecological transitions were seen in the observed Arcellinida communities through the past ca. 6600 cal yBP. Zone 1 spanned ca. 6600-2800 cal yBP and characterized the hydroecology of the lake during the HCO. Zone 2 spanned ca. 2800-140 cal yBP, which represents the Neoglacial. Zone 3 spans ca. 140 cal yBP to present and archives the recovery of the region from the Little Ice Age. Further development of these proxies will help to constrain the rate of climate variability and increase our understanding of the many ways in which the environment responds to climate change. This has implications not only for the Canadian Subarctic but for the Taiga biome, the largest terrestrial biome in the world.
Rhizosphere soil enzymatic and microbial activities in bamboo forests in southeastern China

Abstract Bamboo has been introduced to coastal sandy areas in southeastern China to protect and restore coastal ecosystems. An understanding of the chemistries and enzymatic and microbial activities in the soils of these bamboo forests will aid our understanding of how bamboo plantations can improve soil fertility and will provide scientific evidence for policy makers for encouraging the planting of bamboo in other coastal areas. We investigated the physical and chemical properties of the rhizosphere soil [soil moisture content (SMC), pH, and contents of soil organic matter (SOM), total nitrogen (TN), available nitrogen (AN), total phosphorus (TP), available phosphorus (AP), total potassium (TK) and available potassium (AK)], enzymatic activities (sucrase, protease, urease and catalase) and microbial properties (counts of bacteria, fungi and actinomycetes) in five bamboo forests. The bamboo forests had significantly higher levels of SOM, TN, AN, TP, AP, TK, and AK and lower pH relative to a control soil sample from an area devoid of plants. Soil enzymatic activities and microbial communities were considerably higher in the bamboo forests than in the soil from the barren land. The chemical contents, enzymatic activities and microbial counts of the soil and the litter and root biomasses were higher in forests with the bamboo species Dendrocalamopsis oldhami and Pseudosasa amabilis than in forests with the other three species (Acidosasa edulis, Dendrocalamopsis vario-striata, and Dendrocalamopsis beecheyana var. pubescens), which suggests that these two species could adapt to sandy soil and grow well in a hostile environment. These results indicate that planting bamboo may help to both enrich soil fertility and increase the diversity of tree species in coastal ecosystems. The difference between aboveground and belowground biomass may have been responsible for these changes in soil properties.
Do not always blame the photons: Relationships between deprotection blur, line-edge roughness, and shot noise in extreme ultraviolet photoresists

A corner rounding metric has been used to determine the deprotection blur of Rohm and Haas XP 5435, XP 5271, and XP 5496 extreme ultraviolet (EUV) photoresists as base wt % is varied, an experimental open platform photoresist (EH27) as base wt % is varied, and TOK EUVR P1123 and FUJI 1195 photoresists as postexposure bake temperature is varied. In the XP 5435, XP 5271, XP 5496, and EH27 resist platforms, a six times increase in base wt % reduces the size of successfully patterned 1:1 lines by over 10nm and lowers intrinsic line-edge roughness (LER) by over 2.5nm without changing deprotection blur. In TOK EUVR P1123 photoresist, lowering the PEB temperature from 100to80°C reduces measured deprotection blur (using the corner metric) from 30to20nm and reduces the LER of 50nm 1:1 lines from 4.8to4. 3nm. These data are used to drive a lengthy discussion about the relationships between deprotection blur, LER, and shot noise in EUV photoresists. The authors provide two separate conclusions: (1) shot noise is prob.
Effect of Ramadan fasting on body weight and serum cholesterol in middle aged healthy subjects: An observational trial

Introduction: There are significant changes in the food habits, sleep and behaviour during Ramadan fasting which may significantly impact the body metabolism. This study evaluated effect of Ramadan fasting on body weight and serum cholesterol among normal healthy subjects. Materials and Methods: Thirty normal and apparently healthy subjects in the age group of 35 to 65 years and determined to complete full month of fasting during Ramadan were enrolled in the study. The outcome measures: body weight & serum cholesterol were assessed in all the subjects before and after Ramadan month. Results: The subjects (age: 45.2 ± 7.24 years), underwent a significant decrease in body weight from 60.1 ± 9.4 kg to 58.5 ± 9.2 kg (p Conclusion: Based on findings from our study sample, we conclude that Ramadan fasting by middle aged healthy individuals may lead to reduction in body weight and decrease in serum cholesterol. Keywords: Ramadan fasting, Body weight, Serum cholesterol.
Influence of contacts on the electron transport dynamics inside a mesoscopic system

In mesoscopic systems the Wigner function picture is used for studying electron quantum transport. In this work we present theoretical results on the effect of contact proximity in nanometric devices. If the correlation of the electron wavefunction vanishes inside the contact regions, the transport properties inside the device are affected. We have verified this influence analytically. The main effect is the dependence of the tunnel current through potential barriers on the distance between the contacts. Using three different simulation schemes we have observed modifications in the electron density and conductance for simple devices depending on the distance between the contacts.
Computer Simulations of Polymers Close to Solid Interfaces: Some Selected Topics

This paper presents a topical overview of molecular-dynamics and Monte Carlo simulations for polymer systems close to solid interfaces. The simulations utilize simplified coarse-grained models: The polymers are represented by bead-spring chains, and the walls by a crystalline layer of Lennard-Jones particles or by a smooth impenetrable barrier. This approach has two advantages. First, it reduces the complexity of the simulation. Often, it is only then possible that the interesting length and time scales can be studied at all. Second, the approach concentrates on generic features that are believed to determine the physics of the problem under consideration. The results of the simulation can thus help to single out those features which should be incorporated in an analytical treatment. In this paper, we want to illustrate the versatility of these models by applying them to a broad spectrum of different problems. The situations considered range from the adsorption of a polymer from dilute solution onto a wall, over the importance of sub-monolayer monomeric or polymeric lubricants for kinetic friction, to the crystallization or glass transition of dense polymer films.
Hydrates in the methane‐nitrogen system

The gas hydrate equilibrium curves for systems containing methane and nitrogen have been obtained in the temperature interval 32°F. to 72°F. and between pressures of 350 and 5100 Ib. /sq.in. abs. The composition of the equilibrium gas and hydrate phases was determined experimentally at 32°F. and 44°F. This information was used to calculate vapor-solid equilibrium ratios for both nitrogen and methane. A comparison is made between the equilibrium ratios in this system which crystallizes in Structure I and the ratios in systems reported earlier which crystallize in Structure II. Les courbes d'equilibre de clathrates pour les systemes contenant du methane et de I'azote ont ete obtenues entre les temperatures de 32° a 72°F. et les pressions de 350 a 5100 Ibs/po2. On a determine la composition a I'equilibre entre les phases gaz et clathrate a 32, 39.7 et 44°F. qui a ete utilisee pour calculer le rapport vapeur-solide pour le methane et I'azote. Ce rapport vapeur-solide est compare avec un systeme anterieur qui cristallise differemment.