393 research outputs found

    An Isotropic Metric

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    An isotropic metric for a black hole and a better vacuum condition \nabla^2 V_G =0 are presented which yield distinct terms for the energy densities of ordinary matter and gravitational fields in the Einstein tensor (G^44 =-g^2 (2\nabla^2 V_G +(\nabla V_G)^2)). This model resolves an inconsistency between electromagnetism and gravity in the calculation of field energy. Resolution of this inconsistency suggests a slight modification of the Einstein equation to gG^\mu\nu = 8\pi G T^\mu\nu

    Debate in science: The case of acculturation

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    The acculturation paradigm of measuring assimilation, separation, integration and marginalization confuses dimensional and categorical conceptions of its constructs, fails to produce ipsative data from mutually exclusive scales, misoperationalizes marginalization as distress, mismeasures biculturalism using double-barreled questions instead of computing it from unicultural measures, and then tends to misinterpret and miscite this faulty science. Extensive published but widely uncited data cast doubt on claims that integration is preferred by minority groups or is beneficial for them. Such salient but unseen problems suggest that the community of acculturation researchers is biased and blinded by an ideology, probably the commendable ideology of liberalism, which advocates freedom of choice, tolerance, plurality, and redress of harm. Phenomenological observations that challenge the paradigm include the absence of studies of majority group acculturation, the well-replicated fact that minorities never prefer pure uniculturalism, the indistinctiveness of cultures, and the predominance of researchers, theory and data from similar Anglo-Saxon settler societies (USA, Australia, Canada)

    Historical Trends in the Astronomy, Math, and Physics Section of the Virginia Academy of Science

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    A brief history of the Astronomy, Math, and Physics section of the Virginia Academy of Science is presented, noting trends in participation and content

    The coming PIN code epidemic: A survey study of memory of numeric security codes

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    Most people must remember various numeric passwords, security codes and PIN numbers for banking, credit cards, debit cards, online accounts, mobile phones, door locks, luggage locks, etc. One pilot study (N=13) developed a list of eleven strategies for remembering numeric codes, and another (N=15) optimized the research questionnaire which asked respondents about a) the number of security codes they had, b) the number of self-created codes, c) mnemonic strategies used, d) problems and effort remembering codes, and e) gender, age, and education. Respondents (N=388) had a median of 4 security codes and typically used 2 different memory strategies, the most common of which were based on repetition and on keypad pattern. Difficulties remembering codes were unrelated to gender or education but were positively correlated with age and with number of strategies used. Self-creation of codes slightly reduced difficulties remembering numeric codes

    Preparation, Features, and Efficiency of Nanocomposite Fertilisers Based on Glauconite and Ammonium Dihydrogen Phosphate

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    This paper studies the chemical and mechanochemical preparation of glauconite with ammonium dihydrogen phosphate (ADP) nanocomposites with a ratio of 9:1 in the vol.% and wt.%, respectively. The methods include X-ray diffraction analysis, scanning electron microscope with energy-dispersive X-ray spectroscopy, transmission electron microscopy, infrared spectroscopy, and differential thermal analysis with a quadruple mass spectrometer. The manufactured nanocomposites keep the flaky glauconite structure. Some glauconite unit structures have been thickened due to minimal nitrogen (ammonium) intercalation into the interlayer space. The globular, granular, or pellet mineral particles of nanocomposites can be preserved via chemical techniques. Globular and micro-aggregate particles in nanocomposites comprise a thin film of adsorbed ADP. The two-step mechanochemical method makes it possible to slightly increase the proportion of adsorbed (up to 3.2%) and intercalated (up to 6.0%) nutrients versus chemical ways. Nanocomposites prepared via chemical methods consist of glauconite (90%), adsorbed (1.8–3.6%), and intercalated (3.0–3.7%) substances of ADP. Through the use of a potassium-containing clay mineral as an inhibitor, nitrogen, phosphorus, and potassium (NPK), nanocomposite fertilisers of controlled action were obtained. Targeted and controlled release of nutrients such as phosphate, ammonium, and potassium are expected due to various forms of nutrients on the surface, in the micropores, and in the interlayer space of glauconite. This is confirmed via the stepwise dynamics of the release of ammonium, nitrate, potassium, and phosphate from their created nanocomposites. These features of nanocomposites contribute to the stimulation of plant growth and development when fertilisers are applied to the soil.Russian Science Foundation through the research project 22-77-1000

    Water–rock interaction within the oligotrophic peat bog (part of the Vasyugan Swamp, Western Siberia)

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    Geochemical conditions of the formation of various minerals were studied within the oligotrophic pine-shrub and sphagnum peat bog. It was shown that at least two complex barriers function within the peat deposit. These barriers correspond to the changes in the advective and diffusion transfer of substances and promote the immobilization of Fe and a number of other chemical elements. The upper complex geochemical (redox, sulfide and sorption) barrier occurs approximately at the depths of 0.40 to 1.25 m. The lower complex geochemical (alkaline and sorption) and mechanical barriers are located at the bottom part of the peat deposit (the depth of 2.25–2.50 m)

    Structural-chemical features and morphology of glauconites in sedimentary iron ore of Bakchar prospect (Western Siberia)

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    The research embraces the investigation results of glauconites in Bakchar iron ore occurrences to evaluate the potential diversified commercial application of this mineral. The following lab methods were used to analyze the morphology, chemical composition and structure of glauconites: granulometric analysis, optical microscopy, electron microscopy, X-ray fluorescence analysis, atomic arc-emission analysis and infrared spectroscopy. Glauconite was classified according to morphology and grain color and chemical composition and some specific characteristics were also determined (relative content of absorbed water, random distribution of smectite flakes within the grain structures). The research results showed that pistacho-green glauconite grains are less subjected to alteration than greenish-yellow grains due to the content of potassium, iron, absorbed water and organic impurities

    Mechanochemical Preparation of Slow Release Fertilizer Based on Glauconite–Urea Complexes

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    We investigated the mechanochemical synthesis of complex slow release fertilizers (SRF) derived from glauconite. We studied the effectiveness of the mechanical intercalation of urea into glauconite using planetary and ring mills. The potassium-nitric complex SRFs were synthesized via a mechanochemical method mixing glauconite with urea in a 3:1 ratio. The obtained composites were analyzed using X-ray diffraction analysis, scanning electron microscopy, X-ray fluorescence analysis, and infrared spectroscopy. The results show that as duration of mechanochemical activation increases, the mineralogical, chemical, and structural characteristics of composites change. Essential modifications associated with a decrease in absorbed urea and the formation of microcrystallites were observed when the planetary milling time increased from 5 to 10 min and the ring milling from 15 to 30 min. Complete intercalation of urea into glauconite was achieved by 20 min grinding in a planetary mill or 60 min in a ring mill. Urea intercalation in glauconite occurs much faster when using a planetary mill compared to a ring mill

    Cold-seep carbonates of the Laptev Sea continental slope: Constraints from fluid sources and environment of formation

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    This study presents results of the petrographic, mineralogical, stable isotopes of oxygen and carbon, and trace element investigation of authigenic carbonates collected at newly discovered active cold seeps on the Laptev Sea continental slope at ∼300 m water depth. These carbonates are mainly represented by Mg-calcite with MgCO3 content from 9.1 mol% to 14.0 mol%. The low δ13C values of carbonates ranging from −50.6 ‰ to −32.4 ‰ (V-PDB) indicate that they were formed from anaerobic oxidation of biogenic methane and minor participation of other carbon sources. The difference between measured (from 4.7 ‰ to 5.5 ‰) and calculated (4.0 ‰) δ18Ocarb values might be inherited from fluids enriched in 18O due to dissociation of gas hydrates, which could be the source of methane. The carbonates exhibit weak enrichment in Co, moderate and strong enrichments in As, Mo, and Sb, and strong enrichment in U. Interestingly, As, Sb, and Co correlate with the pyrite content. This indicates that authigenic iron sulfides promote the immobilization of these redox-sensitive elements in seep sediments. The (Mo/U)EF values and anomalies of concentration of Mo and U probably indicate variations in the redox conditions during carbonate formation due to episodically seepage activity changes. Ascending methane-bearing fluids were the main contributor to the enrichment of cold-seep carbonates in As, Mo, Sb, and U at the Laptev Sea continental slope. However additional input from the particulate shuttle process can not be ruled out
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