Articoli di riviste: "Primitive matter"

1

Bhandari, N. "Primitive Matter in Meteorites". Symposium - International Astronomical Union 120 (1987): 485–91. http://dx.doi.org/10.1017/s0074180900154506.

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A large number of elements in certain meteorites have isotopic composition different from that existing in rocks of the earth or the moon. Excess amounts of some isotopes, which are radiogenic daughters, are attributed to the in situ decay of their parent nuclide. Material containing radioactive parents is believed to have been injected into the condensing solar nebula, from astrophysical sites of their production shortly before formation of these grains. Other isotopic anomalies do not show mass dependent pattern which is characteristic of chemical fractionation. They must be primary isotopic abundances, if it is assumed that physico-chemical processes in the solar nebula cannot produce non-mass dependent fractionation. In such a case the observed isotopic ratios characterise elements differently synthesised and injected into the solar nebula which condensed before it had enough time to homogenise. Thus the isotopically anomalous matter has extra solar origin and may contain supernovae condensates, interstellar matter or dust from other stars. The evidence for different isotopic anomalies is briefly summarised and discussed in terms of the current ideas regarding chemical processes occurring in the early solar system.

2

Flynn, G. J., L. P. Keller, S. Wirick e C. Jacobsen. "Organic matter in interplanetary dust particles". Proceedings of the International Astronomical Union 4, S251 (febbraio 2008): 267–76. http://dx.doi.org/10.1017/s174392130802173x.

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AbstractAnhydrous interplanetary dust particles (IDPs), which are the most mineralogically primitive extraterrestrial materials available for laboratory analysis, contain several percent organic matter. The high O:C and N:C ratios suggest the organic matter in the anhydrous IDPs is significantly less altered by thermal processing than the organic matter in meteorites. X-ray Absorption Near-Edge Structure (XANES) spectroscopy and infrared spectroscopy demonstrate the presence of C=C, most likely as C-rings, C=O, and aliphatic C-H2and C-H3in all the IDPs examined. A D-rich spot, containing material that is believed to have formed in a cold molecular cloud, has C-XANES and infrared spectra very similar to the organic matter in the anhydrous IDPs, possibly indicating a common formation mechanism. However the primitive organic matter in the IDPs differs from the interstellar/circumstellar organic matter characterized by astronomical infrared spectroscopy in the relative strengths of the asymmetric aliphatic C-H2and C-H3absorptions, with the IDP organic having a longer mean chain length. If both types of organic matter originated by the same process, this may indicate the interstellar organic matter has experienced more severe radiation processing than the organic matter in the primitive IDPs.

3

Cody, George D., Conel M. O'D Alexander, A. L. David Kilcoyne e Hikaru Yabuta. "Unraveling the chemical history of the Solar System as recorded in extraterrestrial organic matter". Proceedings of the International Astronomical Union 4, S251 (febbraio 2008): 277–84. http://dx.doi.org/10.1017/s1743921308021741.

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AbstractWe have initiated an extensive program of molecular analysis of extraterrestrial organic matter isolated from a broad range of meteorites (spanning multiple classes, groups, and petrologic types), including recent molecular spectroscopic analyses of the organic matter in the Comet 81P/Wild 2 samples. The results of these analyses clearly reveal the signature of multiple reaction pathways that transformed extraterrestrial organic matter away from its primitive roots. The most significant molecular transformation occurred in the post-accretionary phase of the parent body. However, each of the various chemical transformation trajectories point unambiguously back to a common primitive origin. Applying a wide range of spectroscopic techniques we find that the primitive organic precursor is striking in its chemical complexity exhibiting a broad array of oxygen- and nitrogen-bearing functional groups. The π-bonded carbon exists as predominately highly substituted single ring aromatics, there exists no evidence for abundant, large, polycyclic aromatic hydrocarbons (PAHs). We find that the molecular structure of primitive extraterrestrial organics is consistent with synthesis from small reactive molecules, e. g. formaldehyde, whose random condensation and subsequent rearrangement chemistry at low temperatures leads to a highly cross-linked macromolecule.

4

Libourel, Guy, Patrick Michel, Marco Delbo, Clément Ganino, Alejandra Recio-Blanco, Patrick de Laverny, Michael E. Zolensky e Alexander N. Krot. "Search for primitive matter in the Solar System". Icarus 282 (gennaio 2017): 375–79. http://dx.doi.org/10.1016/j.icarus.2016.09.014.

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Wooden, D. H., H. A. Ishii e M. E. Zolensky. "Cometary dust: the diversity of primitive refractory grains". Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences 375, n. 2097 (29 maggio 2017): 20160260. http://dx.doi.org/10.1098/rsta.2016.0260.

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Comet dust is primitive and shows significant diversity. Our knowledge of the properties of primitive cometary particles has expanded significantly through microscale investigations of cosmic dust samples (anhydrous interplanetary dust particles (IDPs), chondritic porous (CP) IDPs and UltraCarbonaceous Antarctic micrometeorites, Stardust and Rosetta ), as well as through remote sensing ( Spitzer IR spectroscopy). Comet dust are aggregate particles of materials unequilibrated at submicrometre scales. We discuss the properties and processes experienced by primitive matter in comets. Primitive particles exhibit a diverse range of: structure and typology; distribution of constituents; concentration and form of carbonaceous and refractory organic matter; Mg- and Fe-contents of the silicate minerals; sulfides; existence/abundance of type II chondrule fragments; high-temperature calcium–aluminium inclusions and ameboid-olivine aggregates; and rarely occurring Mg-carbonates and magnetite, whose explanation requires aqueous alteration on parent bodies. The properties of refractory materials imply there were disc processes that resulted in different comets having particular selections of primitive materials. The diversity of primitive particles has implications for the diversity of materials in the protoplanetary disc present at the time and in the region where the comets formed. This article is part of the themed issue ‘Cometary science after Rosetta’.

6

Messenger, Scott, e K. Nakamura-Messenger. "Interstellar and Solar System organic matter preserved in interplanetary dust". Proceedings of the International Astronomical Union 11, A29B (agosto 2015): 426. http://dx.doi.org/10.1017/s1743921316005718.

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AbstractInterplanetary dust particles (IDPs) collected in the Earths stratosphere derive from collisions among asteroids and by the disruption and outgassing of short-period comets. Chondritic porous (CP) IDPs are among the most primitive Solar System materials. CP-IDPs have been linked to cometary parent bodies by their mineralogy, textures, C-content, and dynamical histories. CP-IDPs are fragile, fine-grained (< um) assemblages of anhydrous amorphous and crystalline silicates, oxides and sulfides bound together by abundant carbonaceous material. Ancient silicate, oxide, and SiC stardust grains exhibiting highly anomalous isotopic compositions are abundant in CP-IDPs, constituting 0.01-1% of the mass of the particles. The organic matter in CP-IDPs is isotopically anomalous, with enrichments in D/H reaching 50x the terrestrial SMOW value and 15N/14N ratios up to 3x terrestrial standard compositions. These anomalies are indicative of low T (10-100 K) mass fractionation in cold molecular cloud or the outermost reaches of the protosolar disk. The organic matter shows distinct morphologies, including sub-um globules, bubbly textures, featureless, and with mineral inclusions. Infrared spectroscopy and mass spectrometry studies of organic matter in IDPs reveals diverse species including aliphatic and aromatic compounds. The organic matter with the highest isotopic anomalies appears to be richer in aliphatic compounds. These materials also bear similarities and differences with primitive, isotopically anomalous organic matter in carbonaceous chondrite meteorites. The diversity of the organic chemistry, morphology, and isotopic properties in IDPs and meteorites reflects variable preservation of interstellar/primordial components and Solar System processing. One unifying feature is the presence of sub-um isotopically anomalous organic globules among all primitive materials, including IDPs, meteorites, and comet Wild-2 samples returned by the Stardust mission. We will present an overview of the current state of understanding of the properties and origins of organic matter in primitive IDPs.

7

Hui, Zhenyang, Zhaochen Cai, Bo Liu, Dajun Li, Hua Liu e Zhuoxuan Li. "A Self-Adaptive Optimization Individual Tree Modeling Method for Terrestrial LiDAR Point Clouds". Remote Sensing 14, n. 11 (26 maggio 2022): 2545. http://dx.doi.org/10.3390/rs14112545.

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Individual tree modeling for terrestrial LiDAR point clouds always involves heavy computation burden and low accuracy toward a complex tree structure. To solve these problems, this paper proposed a self-adaptive optimization individual tree modeling method. In this paper, we first proposed a joint neighboring growing method to segment wood points into object primitives. Subsequently, local object primitives were optimized to alleviate the computation burden. To build the topology relation among branches, branches were separated based on spatial connectivity analysis. And then the nodes corresponding to each object primitive were adopted to construct the graph structure of the tree. Furthermore, each object primitive was fitted as a cylinder. To revise the local abnormal cylinder, a self-adaptive optimization method based on the constructed graph structure was proposed. Finally, the constructed tree model was further optimized globally based on prior knowledge. Twenty-nine field datasets obtained from three forest sites were adopted to evaluate the performance of the proposed method. The experimental results show that the proposed method can achieve satisfying individual tree modeling accuracy. The mean volume deviation of the proposed method is 1.427 m3. In the comparison with two other famous tree modeling methods, the proposed method can achieve the best individual tree modeling result no matter which accuracy indicator is selected.

8

Busemann, H. "Interstellar Chemistry Recorded in Organic Matter from Primitive Meteorites". Science 312, n. 5774 (5 maggio 2006): 727–30. http://dx.doi.org/10.1126/science.1123878.

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9

Kuga, Maïa, Bernard Marty, Yves Marrocchi e Laurent Tissandier. "Synthesis of refractory organic matter in the ionized gas phase of the solar nebula". Proceedings of the National Academy of Sciences 112, n. 23 (26 maggio 2015): 7129–34. http://dx.doi.org/10.1073/pnas.1502796112.

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In the nascent solar system, primitive organic matter was a major contributor of volatile elements to planetary bodies, and could have played a key role in the development of the biosphere. However, the origin of primitive organics is poorly understood. Most scenarios advocate cold synthesis in the interstellar medium or in the outer solar system. Here, we report the synthesis of solid organics under ionizing conditions in a plasma setup from gas mixtures (H2(O)−CO−N2−noble gases) reminiscent of the protosolar nebula composition. Ionization of the gas phase was achieved at temperatures up to 1,000 K. Synthesized solid compounds share chemical and structural features with chondritic organics, and noble gases trapped during the experiments reproduce the elemental and isotopic fractionations observed in primitive organics. These results strongly suggest that both the formation of chondritic refractory organics and the trapping of noble gases took place simultaneously in the ionized areas of the protoplanetary disk, via photon- and/or electron-driven reactions and processing. Thus, synthesis of primitive organics might not have required a cold environment and could have occurred anywhere the disk is ionized, including in its warm regions. This scenario also supports N2 photodissociation as the cause of the large nitrogen isotopic range in the solar system.

10

VLČCEK, LUKÁ[Sbreve]C, e IVO NEZBEDA. "From realistic to primitive models: a primitive model of methanol". Molecular Physics 101, n. 19 (10 ottobre 2003): 2987–96. http://dx.doi.org/10.1080/00268970310001605750.

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11

Ortega-Casanova, J., M. Ortega-Cortes, P. Cortes-Carretero e J. Ortega-Cortes. "A primitive method for cooling water: does the shape matter?" Case Studies in Thermal Engineering 26 (agosto 2021): 101022. http://dx.doi.org/10.1016/j.csite.2021.101022.

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12

Antognazza, Maria Rosa. "Primary Matter, Primitive Passive Power, and Creaturely Limitation in Leibniz". Studia Leibnitiana 46, n. 2 (2014): 167–86. http://dx.doi.org/10.25162/sl-2014-0011.

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13

Stinchcombe, Robin. "Primitive cooperative particle flow models". Physica A: Statistical Mechanics and its Applications 372, n. 1 (dicembre 2006): 1–11. http://dx.doi.org/10.1016/j.physa.2006.05.013.

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14

Nezbeda, Ivo, Jiří Kolafa e Yurij Kalyuzhnyi. "Primitive model of water". Molecular Physics 68, n. 1 (1 settembre 1989): 143–60. http://dx.doi.org/10.1080/00268978900102021.

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15

Nezbeda, Ivo, e Gustavo A. Iglesias-Silva. "Primitive model of water". Molecular Physics 69, n. 4 (marzo 1990): 767–74. http://dx.doi.org/10.1080/00268979000100561.

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16

Santos, Manuel B., Paulo Mateus e Armando N. Pinto. "Quantum Oblivious Transfer: A Short Review". Entropy 24, n. 7 (7 luglio 2022): 945. http://dx.doi.org/10.3390/e24070945.

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Quantum cryptography is the field of cryptography that explores the quantum properties of matter. Generally, it aims to develop primitives beyond the reach of classical cryptography and to improve existing classical implementations. Although much of the work in this field covers quantum key distribution (QKD), there have been some crucial steps towards the understanding and development of quantum oblivious transfer (QOT). One can show the similarity between the application structure of both QKD and QOT primitives. Just as QKD protocols allow quantum-safe communication, QOT protocols allow quantum-safe computation. However, the conditions under which QOT is fully quantum-safe have been subject to intense scrutiny and study. In this review article, we survey the work developed around the concept of oblivious transfer within theoretical quantum cryptography. We focus on some proposed protocols and their security requirements. We review the impossibility results that daunt this primitive and discuss several quantum security models under which it is possible to prove QOT security.

17

YAMAMOTO, Tetsuo. "Chemical Composition and Origin of Primitive Matter of the Solar System." Journal of the Mineralogical Society of Japan 20, n. 4 (1991): 187–92. http://dx.doi.org/10.2465/gkk1952.20.187.

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Gay, Fabrizio, e Irene Cazzaro. "Self-organized matter: design and primitive future of the eidetic categories". Design Journal 20, sup1 (28 luglio 2017): S317—S331. http://dx.doi.org/10.1080/14606925.2017.1352849.

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19

Busemann, Henner, M. O'D Alexander e Larry R. Nittler. "Characterization of insoluble organic matter in primitive meteorites by microRaman spectroscopy". Meteoritics & Planetary Science 42, n. 7-8 (agosto 2007): 1387–416. http://dx.doi.org/10.1111/j.1945-5100.2007.tb00581.x.

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20

Egg, Matthias, e Michael Esfeld. "Primitive ontology and quantum state in the GRW matter density theory". Synthese 192, n. 10 (8 novembre 2014): 3229–45. http://dx.doi.org/10.1007/s11229-014-0590-3.

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21

Sciortino, Francesco. "Primitive models of patchy colloidal particles. A review". Collection of Czechoslovak Chemical Communications 75, n. 3 (2010): 349–58. http://dx.doi.org/10.1135/cccc2009109.

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In this article I will review some recent studies of the phase behavior and of the self-assembly of patchy colloidal particles. These studies have been based on simple primitive models for colloid–colloid interactions, effectively extending to soft matter the seminal work of I. Nezbeda on associated fluids. I will discuss the possibilities offered by the study of the self-assembly of particles with limited valence in deepening our understanding of the onset of the liquid state, of the differences between gels and glasses and of the possible connection between physical and chemical gels. A review with 55 references.

22

Messenger, S. "Interstellar Matter in Meteorites and Interplanetary Dust". Symposium - International Astronomical Union 197 (2000): 527–36. http://dx.doi.org/10.1017/s0074180900165088.

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Meteorites and interplanetary dust particles (IDPs) are primitive solar system materials which contain preserved nebular condensates, circumstellar dust grains and partially preserved molecular cloud matter. The circumstellar dust grains found in meteorites are direct samples of a variety of stars, and provide detailed constraints on models of stellar nucleosynthesis. Hydrogen and nitrogen isotopic anomalies in organic matter in meteorites and IDPs are thought to originate from chemical processes in a presolar molecular cloud. This material is better preserved, but less well characterized among IDPs.

23

Maupin, Romain, Zahia Djouadi, Rosario Brunetto, Obadias Mivumbi, Christophe Sandt e Ferenc Borondics. "Polyaromatic Units Set the Albedo of Dark Extraterrestrial Materials". Planetary Science Journal 3, n. 1 (1 gennaio 2022): 10. http://dx.doi.org/10.3847/psj/ac424b.

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Abstract Primitive extraterrestrial materials are generally dark, a characteristic often associated with the presence of polyaromatic organic material and/or sulfides. We show in this study that the reflectance level measured at 0.55 μm of IDPs and some meteorites is correlated to the degree of graphitization of the polyaromatic organic matter. The reflectance level of the primitive surfaces therefore allows us to obtain information on the polyaromatic organic material present on the surface of solar system small bodies observed by remote sensing or visited by space missions. We discuss our results in view of the sample return missions Hayabusa2 and OSIRIS-REx.

24

van Dishoeck, Ewine F. "Organic matter in space - An overview". Proceedings of the International Astronomical Union 4, S251 (febbraio 2008): 3–16. http://dx.doi.org/10.1017/s1743921308021078.

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AbstractOrganic compounds are ubiquitous in space: they are found in diffuse clouds, in the envelopes of evolved stars, in dense star-forming regions, in protoplanetary disks, in comets, on the surfaces of minor planets, and in meteorites and interplanetary dust particles. This brief overview summarizes the observational evidence for the types of organics found in these regions, with emphasis on recent developments. The Stardust sample-return mission provides the first opportunity to study primitive cometary material with sophisticated equipment on Earth. Similarities and differences between the types of compounds in different regions are discussed in the context of the processes that can modify them. The importance of laboratory astrophysics is emphasized.

25

Kolafa, Jiří, e Ivo Nezbeda. "Primitive models of associated liquids". Molecular Physics 72, n. 4 (marzo 1991): 777–85. http://dx.doi.org/10.1080/00268979100100551.

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Madsen, M. B., S. Mørup, T. V. V. Costa, J. M. Knudsen e M. Olsen. "Superparamagnetism in primitive meteorites". Hyperfine Interactions 41, n. 1 (dicembre 1988): 827–30. http://dx.doi.org/10.1007/bf02400518.

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MARROCCHI, Y., S. DERENNE, B. MARTY e F. ROBERT. "Interlayer trapping of noble gases in insoluble organic matter of primitive meteorites". Earth and Planetary Science Letters 236, n. 3-4 (15 agosto 2005): 569–78. http://dx.doi.org/10.1016/j.epsl.2005.04.010.

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McKay, Adam J., e Nathan X. Roth. "Organic Matter in Cometary Environments". Life 11, n. 1 (8 gennaio 2021): 37. http://dx.doi.org/10.3390/life11010037.

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Comets contain primitive material leftover from the formation of the Solar System, making studies of their composition important for understanding the formation of volatile material in the early Solar System. This includes organic molecules, which, for the purpose of this review, we define as compounds with C–H and/or C–C bonds. In this review, we discuss the history and recent breakthroughs of the study of organic matter in comets, from simple organic molecules and photodissociation fragments to large macromolecular structures. We summarize results both from Earth-based studies as well as spacecraft missions to comets, highlighted by the Rosetta mission, which orbited comet 67P/Churyumov–Gerasimenko for two years, providing unprecedented insights into the nature of comets. We conclude with future prospects for the study of organic matter in comets.

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McKay, Adam J., e Nathan X. Roth. "Organic Matter in Cometary Environments". Life 11, n. 1 (8 gennaio 2021): 37. http://dx.doi.org/10.3390/life11010037.

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Comets contain primitive material leftover from the formation of the Solar System, making studies of their composition important for understanding the formation of volatile material in the early Solar System. This includes organic molecules, which, for the purpose of this review, we define as compounds with C–H and/or C–C bonds. In this review, we discuss the history and recent breakthroughs of the study of organic matter in comets, from simple organic molecules and photodissociation fragments to large macromolecular structures. We summarize results both from Earth-based studies as well as spacecraft missions to comets, highlighted by the Rosetta mission, which orbited comet 67P/Churyumov–Gerasimenko for two years, providing unprecedented insights into the nature of comets. We conclude with future prospects for the study of organic matter in comets.

30

Isnard, R., A. Bardyn, N. Fray, C. Briois, H. Cottin, J. Paquette, O. Stenzel et al. "H/C elemental ratio of the refractory organic matter in cometary particles of 67P/Churyumov-Gerasimenko". Astronomy & Astrophysics 630 (20 settembre 2019): A27. http://dx.doi.org/10.1051/0004-6361/201834797.

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Context. Because comets are part of the most primitive bodies of our solar system, establishing their chemical composition and comparing them to other astrophysical bodies gives new constraints on the formation and evolution of organic matter throughout the solar system. For two years, the time-of-flight secondary ion mass spectrometer COmetary Secondary Ion Mass Analyzer (COSIMA) on board the Rosetta orbiter performed in situ analyses of the dust particles ejected from comet 67P/Churyumov-Gerasimenko (67P). Aims. The aim is to determine the H/C elemental ratio of the refractory organic component contained in cometary particles of 67P. Methods. We analyzed terrestrial and extraterrestrial calibration samples using the COSIMA ground-reference model. Exploiting these calibration samples, we provide calibration lines in both positive and negative ion registration modes. Thus, we are now able to measure the cometary H/C elemental ratio. Results. The mean H/C value is 1.04 ± 0.16 based on 33 different cometary particles. Consequently, the H/C atomic ratio is on average higher in cometary particles of 67P than in even the most primitive insoluble organic matter extracted from meteorites. Conclusions. These results imply that the refractory organic matter detected in dust particles of 67P is less unsaturated than the material in meteorites.

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Hirschfelder, Joseph O. "Primitive exchange perturbation theory, IV". International Journal of Quantum Chemistry 5, S4 (18 giugno 2009): 257–69. http://dx.doi.org/10.1002/qua.560050728.

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Patsahan, O. V., e I. M. Mryglod. "Critical behaviour of the restricted primitive model". Journal of Physics: Condensed Matter 16, n. 16 (9 aprile 2004): L235—L241. http://dx.doi.org/10.1088/0953-8984/16/16/l01.

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Masubuchi, Yuichi, Giovanni Ianniruberto, Francesco Greco e Giuseppe Marrucci. "Primitive chain network simulations for branched polymers". Rheologica Acta 46, n. 2 (23 maggio 2006): 297–303. http://dx.doi.org/10.1007/s00397-006-0112-4.

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Meléndez-López, A., M. F. García-Hurtado, J. Cruz-Castañeda, A. Negrón-Mendoza, S. Ramos-Bernal e A. Heredia. "Gamma Irradiation of Aqueos Solution of L-Aspartic Acid, L-Aspartic Acid in Solid State, and L-Aspartic Acid Adsorbed into Na-Montmorillonite: Its Relevance in Chemistry Prebiotic". Journal of Nuclear Physics, Material Sciences, Radiation and Applications 8, n. 2 (10 febbraio 2021): 105–8. http://dx.doi.org/10.15415/jnp.2021.82012.

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Aspartic acid is an amino acid present in the modern proteins, however, is considered a primitive amino acid hence its importance in prebiotic chemistry experiments studies. In some works of prebiotic chemistry have been studied the synthesis and the stability of organic matter under high energy sources, and the role of clays has been highlighted due to clays that can affect the reaction mechanisms in the radiolytic processes. The present work is focused on the study of the role of Namontmorillonite in the gamma radiolysis processes of L-aspartic acid. Gamma radiolysis processes were carried out in three different systems a) L-aspartic acid in aqueous solution; b) L-aspartic acid in solid-state; and c) L-aspartic acid adsorbed into Na-montmorillonite. L-aspartic acid was analyzed by high-performance liquid chromatography−electrospray ionization−mass spectrometry (HPLCESI-MS). The results showed that the decomposition of L-aspartic acid considerably decreased in the presence of clay thus highlighting the protector role of clays and favors the stability of organic matter even under the possible high energy conditions of primitive environments. The principal product ofgamma radiolysis of L-aspartic acid was succinic acid produced by deamination reaction. On the other hand, when aspartic acid was irradiated in solid-state the main product was the L-aspartic acid dimer. Both radiolysis products are important for chemical evolution processes for L-aspartic acid in primitive environments.

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STRNAD, MARTIN, e IVO NEZBEDA. "Extended primitive models of water revisited". Molecular Physics 93, n. 1 (1 gennaio 1998): 25–30. http://dx.doi.org/10.1080/00268979809482185.

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NEZBEDA, MARTIN STRNAD IVO. "Extended primitive models of water revisited". Molecular Physics 93, n. 1 (gennaio 1998): 25–30. http://dx.doi.org/10.1080/002689798169401.

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Kuehni, Rolf. "Focal Color Variability and Unique Hue Stimulus Variability". Journal of Cognition and Culture 5, n. 3-4 (2005): 409–26. http://dx.doi.org/10.1163/156853705774648554.

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AbstractThe degree to which physiology and culture have affected the formation of primitive color categories continues to be a matter of discussion. In this paper the degree of agreement between the ranges of individual color term foci for the four hue-based color categories yellow, green, blue, and red and individual choices of Munsell samples representing for the observers Hering's four unique hues is investigated. The color term focus range data are extracted from the survey results of the 110 unwritten languages of the World Color Survey, also in terms of the Munsell color order system. Agreement of approximately 90% between the two has been found, indicating the likelihood of a strong color vision system related physiological component in the formation of these four primitive hue categories.

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Patsahan. "PHASE BEHAVIOUR OF THE RESTRICTED PRIMITIVE MODEL". Condensed Matter Physics 7, n. 1 (2004): 35. http://dx.doi.org/10.5488/cmp.7.1.35.

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De Gregorio, Bradley T., Rhonda M. Stroud, Kate D. Burgess e Conel M. O'D Alexander. "Nanoscale Variation in Carbonaceous Matter from Primitive Meteorites Revealed by Aberration-Corrected STEM". Microscopy and Microanalysis 21, S3 (agosto 2015): 2265–66. http://dx.doi.org/10.1017/s1431927615012106.

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Martins, Zita, e Matthew A. Pasek. "Delivery of Organic Matter to the Early Earth". Elements 20, n. 1 (1 febbraio 2024): 19–23. http://dx.doi.org/10.2138/gselements.20.1.19.

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The inner Solar System—including the planet Earth—was heavily bombarded by comets, asteroids, and their fragments (i.e., meteorites, micrometeorites, and interplanetary dust particles) from 4.56 to about 3.5 billion years ago. This bombardment resulted in a rich assortment of organics delivered to the Earth, as comets and many asteroids contain carbonaceous material. These organic compounds were likely further processed on the early Earth (e.g., by impact-shock reactions), providing a feedstock of prebiotic molecules to the crust and oceans. In this chapter, we review the mechanisms of organic matter delivery to the primitive Earth, further reactions and processing, and the importance of exogenous material in the evolution of our planet and life.

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ARONOV, D. V., I. R. LEVINA e I. M. SMIRNOV. "PROTECTION OF PRIMITIVE TRIBES IN INTERNATIONAL ENVIRONMENTAL LAW OF THE EARLY XX CENTURY". JOURNAL OF PUBLIC AND MUNICIPAL ADMINISTRATION 10, n. 2 (2021): 173–79. http://dx.doi.org/10.22394/2225-8272-2021-10-2-173-179.

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The goal of this article is to analyze primitive tribes as a legal subject or subject-matter of the international environmental law of the early twentieth century. The article presents the analysis of the object and subjects formation of the international environmental law legal protection on the example of Berne Conference of Experts in 1913. The issue of preserving the habitat and the lifestyle of national-ities leading a primitive way of life is considered. Nowa-days, the primacy of human rights and freedoms as the system-forming center of modern political systems and regimes is not seriously disputed by anyone. The slightest attempts to talk about the prevalence of other values (state, religious) are perceived as an attempt at sacrilege during the period of the Catholic religion dogmas dominance in Europe.

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Zhilinskii, Boris. "On the number ofk-faces of primitive parallelohedra". Acta Crystallographica Section A Foundations and Advances 71, n. 2 (4 febbraio 2015): 212–15. http://dx.doi.org/10.1107/s205327331402806x.

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Dehn–Sommerville relations for simple (simplicial) polytopes are applied to primitive parallelohedra. New restrictions on numbers ofk-faces of non-principal primitive parallelohedra are explicitly formulated for five-, six- and seven-dimensional parallelohedra.

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De Gregorio, Bradley T., e Cécile Engrand. "Diversity of Complex Organic Matter in Carbonaceous Chondrites, IDPs, and UCAMMs". Elements 20, n. 1 (1 febbraio 2024): 24–30. http://dx.doi.org/10.2138/gselements.20.1.24.

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Complex organic matter is present in many extraterrestrial materials such as chondrite meteorites, micrometeorites, and interplanetary dust. The observed complexity of this organic matter is due to the combination of diversity of primitive organic materials that accreted onto asteroids and the subsequent effect of hydrothermal and/or metamorphic alteration that took place after accretion. These processes resulted in a variety of carbonaceous grain morphologies, elemental abundances, and organic functional group compositions. Some carbonaceous dust grains and micrometeorites have cometary origins and provide insights into the unique processing histories on those outer Solar System bodies. Isotopic analyses can help distinguish carbonaceous grains that retain their pre-accretion heritage, while advanced microscopy techniques reveal the interplay of complex organic matter with surrounding mineral.

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Lei, Lijian, Linchang Miao, Chao Li, Xiaodong Liang e Junjie Wang. "The effects of composite primitive cells on band gap property of locally resonant phononic crystal". Modern Physics Letters B 35, n. 20 (20 maggio 2021): 2150334. http://dx.doi.org/10.1142/s0217984921503346.

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Locally resonant phononic crystal (LRPC) has the extraordinary property to prohibit the wave propagation in specific low-frequency ranges, however it exists limitation in engineering application due to narrow band gap width. Extensive achievements have been obtained on the locally resonant band gap (LRBG) tunability, whereas existing investigations mainly concern the independent primitive cells structure, which have the limitation in obtaining low-frequency and broadband simultaneously. In this paper, the composited locally resonant phononic crystals (CLRPC) are proposed and the effects of primitive cells contact state on the LRBG properties are investigated. The dispersion curves are applied to obtain the LRBG, and the corresponding modal features are analyzed to explain the band gap formation mechanism. The band structure indicates the design of composite primitive cells is able to increase the band gap number and obtain lower band gap, which is verified by the frequency response function (FRF). For the band gap formation mechanism, the asymmetric vibration due to primitive cells contact leads to diverse and strong coupling response, which generates more band gaps and reduces the band gap starting frequency, therefore the band gaps can be tuned by designing carefully the geometry structure of CLRPC. Further researches on band gap optimization demonstrate that the smaller cell spacing, smaller lattice constant and larger damping of coating layer should be satisfied to obtain broader LRBG and considerable attenuation synchronously. This investigation can provide references for the locally resonant isolation structure design in the low-frequency vibration control field.

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Pitzer, Kenneth S., e Donald R. Schreiber. "The restricted primitive model for ionic fluids". Molecular Physics 60, n. 5 (10 aprile 1987): 1067–78. http://dx.doi.org/10.1080/00268978700100711.

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Andrecut, Mircea. "Patterns Formation in a Primitive Life Form Model". International Journal of Modern Physics B 12, n. 27n28 (10 novembre 1998): 2881–88. http://dx.doi.org/10.1142/s0217979298001691.

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A computational study of population dynamics in a primitive life form model is presented. The spatio-temporal dependencies of density were calculated for different values of the control parameters (birth and death rates). The calculations have shown that the dynamics of the investigated system lead to the formation of patterns and self-organization only for a certain dependence between the control parameters.

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Carvalho, Richard. "PSYCHIC RETREATS REVISITED: BINDING PRIMITIVE DESTRUCTIVENESS, OR SECURING THE OBJECT? A MATTER OF EMPHASIS?" British Journal of Psychotherapy 19, n. 2 (dicembre 2002): 153–71. http://dx.doi.org/10.1111/j.1752-0118.2002.tb00071.x.

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Delpoux, Olivier, Didier Gourier, Laurent Binet, Hervé Vezin, Sylvie Derenne e François Robert. "CW- and pulsed-EPR of carbonaceous matter in primitive meteorites: Solving a lineshape paradox". Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy 69, n. 5 (maggio 2008): 1301–10. http://dx.doi.org/10.1016/j.saa.2007.09.045.

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Godoy, Ricardo, Dean S. Karlan, Shanti Rabindran e Tomás Huanca. "Do modern forms of human capital matter in primitive economies? Comparative evidence from Bolivia". Economics of Education Review 24, n. 1 (febbraio 2005): 45–53. http://dx.doi.org/10.1016/j.econedurev.2003.11.008.

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REMUSAT, L., F. PALHOL, F. ROBERT, S. DERENNE e C. FRANCELANORD. "Enrichment of deuterium in insoluble organic matter from primitive meteorites: A solar system origin?" Earth and Planetary Science Letters 243, n. 1-2 (15 marzo 2006): 15–25. http://dx.doi.org/10.1016/j.epsl.2005.12.010.

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