Structural Studies of the Alkali Metal Picrates

1995 ◽  
Vol 48 (7) ◽  
pp. 1311 ◽  
Author(s):  
JM Harrowfield ◽  
BW Skelton ◽  
AH White
Keyword(s):  
Alkali Metal ◽  
Sodium Salt ◽  
The Other ◽  
Two Dimensional ◽  
Phenolic Oxygen ◽  
Metal Atoms ◽  
Group Oxygen ◽  
The One ◽  
Potassium Picrate ◽  
Oxygen Atoms

A comparative series of room-temperature, single-crystal X-ray studies of the alkali metal (and ammonium) picrate structures is presented, all being in some sense revisitations of earlier work of various vintages, except for that of the sodium salt. Lithium picrate monohydrate is triclinic, Pī, a 10.710(6), b 7.186(1), c 7.112(1) Ǻ, α 65.89(1), β 71.90(3), γ 84.45(2)°, Z = 2 f.u.; conventional R on |F| was 0.053 for No = 1792 'observed' (I > 3σ(I)) reflections. Sodium picrate monohydrate is monoclinic, C 2/m, a 13.074(6), b 20.080(6), c 3.690(3) Ǻ, β 90.67(3)°, Z = 4 f.u.; R was 0.056 for No 519. Potassium picrate (anhydrous) is orthorhombic, Ibca , a 13.316(3), b 19.107(5), c 7.138(2) Ǻ, Z = 8 f.u ., R 0.036 for No 1308; the ammonium salt is isomorphous, a 13.474(4), b 19.790(7), c 7.131 (4) Ǻ, R 0.040 for No 981. Rubidium picrate (anhydrous) is monoclinic, P 21/c, a 10.604(1), b 4.556(3), c 19.183(2) Ǻ, β 101.41(1)°, Z = 4 f.u ., R 0.039 for No 1878; the caesium salt is isomorphous, a 10.810(1), b 4.700(1), c 19.400(3) Ǻ, β 101.43(1)°, R 0.027 for No 2177. The lithium salt is binuclear, the phenolic oxygen atoms bridging the five-coordinate lithium atoms, while the sodium salt is a two-dimensional polymer parallel to the ab plane, the picrates cross-linking one-dimensional arrays of sodium atoms of two types, one eight-coordinate and linked by bridging phenolic oxygen atoms, and the other six-coordinate and linked by water molecules. The potassium and ammonium salts are also two-dimensional polymers parallel to the ab planes, linked in the second dimension by pairs of picrates opposed in polarity and linking the eight-coordinate potassium atoms by phenolic oxygen atoms on the one hand, and the 4-nitro group oxygen atoms on the other. The rubidium and caesium salts are two-dimensional polymers in the ac plane, eight-coordinate metal atoms being linked by a complex web of picrate groups; unlike the other compounds, they do not contain bridging phenolic oxygen atoms.

scholarly journals ‘Eye-Like Radiance’: The Depiction of Gemstones in Roman Wall Painting

Arts ◽  
2019 ◽  
Vol 8 (2) ◽  
pp. 60
Author(s):  
Ruth Allen
Keyword(s):  
Wall Painting ◽  
The Other ◽  
Two Dimensional ◽  
Dimensional Representation ◽  
Roman Art ◽  
Roman Wall Painting ◽  
The One ◽  
Precious Stones

The study of ornament in Greek and Roman art has been the focus of increasing scholarly interest over the last decade, with many publications shedding new light on the dynamics of ornatus in antiquity, and the discourses that shaped and situated it. Through an analysis of the depiction of gemstones in Roman wall painting, this article demonstrates the importance of ornamental details both to the mechanics of two-dimensional representation and to the interpretation of the images they adorned. I argue that by evoking the material qualities and sensual pleasures of real precious stones, painted gems served on the one hand to enhance the illusory reality of wall painting, and on the other to extol the delights of luxury and refinement—that is, of ornamentation itself.

scholarly journals Crystal structure and Hirshfeld surface analysis of (2E)-1-(3-bromophenyl)-3-(4-fluorophenyl)prop-2-en-1-one

2019 ◽  
Vol 75 (2) ◽  
pp. 146-149
Author(s):  
Zeliha Atioğlu ◽  
S. Bindya ◽  
Mehmet Akkurt ◽  
C. S. Chidan Kumar
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Surface Analysis ◽  
Crystal Packing ◽  
Hirshfeld Surface ◽  
The Other ◽  
Hirshfeld Surface Analysis ◽  
Two Dimensional ◽  
Compound C ◽  
The One

In the title compound, C15H10BrFO, the molecular structure consists of a 3-bromophenyl ring and a 4-fluorophenyl ring linked via a prop-2-en-1-one spacer. The 3-bromophenyl and 4-fluorophenyl rings make a dihedral angle of 48.90 (15)°. The molecule has an E configuration about the C=C bond and the carbonyl group is syn with respect to the C=C bond. In the crystal, molecules are linked by C—H...π interactions between the bromophenyl and fluorophenyl rings of molecules, resulting in a two-dimensional layered structure parallel to the ab plane. The molecular packing is stabilized by weak Br...H and F...H contacts, one of which is on the one side of each layer, and the second is on the other. The intermolecular interactions in the crystal packing were further analysed using Hirshfeld surface analysis, which indicates that the most significant contacts are Cl...H/H...Cl (20.8%), followed by C...H/H...C (31.1%), H...H (21.7%), Br...H/H...Br (14.2%), F...H/H...F (9.8%), O...H/H...O (9.7%).

scholarly journals Characterization of the Structure of 2-(4-methyl-2 Phenyl-4, 5-dihydrooxazol-4-ylmethyl)-isoindole-1, 3-dione by 1D, COSY and HSQC 2D NMR Spectroscopy

2021 ◽  
pp. 30-37
Author(s):  
Khadim Dioukhane ◽  
Younas Aouine ◽  
Asmae Nakkabi ◽  
Salaheddine Boukhssas ◽  
Hassane Faraj ◽  
...  
Keyword(s):  
Nmr Spectroscopy ◽  
2D Nmr ◽  
The Other ◽  
Two Dimensional ◽  
Hsqc Spectrum ◽  
2D Nmr Spectroscopy ◽  
Perfect Correlation ◽  
Dione Derivative ◽  
The One

The identity of the 2-(4-Methyl-2-phenyl-4,5-dihydrooxazol-4-ylmethyl)-isoindole-1,3-dione, previously synthesized in our laboratory, was proven without doubt by means of 1D and 2D NMR spectroscopy. Two-dimensional NMR spectroscopy played a major role. The analysis of the 2D-COSY spectrum of isoindoline-1,3-dione derivative shows a perfect correlation between neighboring protons. Thus, a correlation was noted between the protons of the phthalimide, H(8) and H(9) on the one hand and H(8') and H(9') on the other hand. The analysis of the 2D-HSQC spectrum of the studied compound indicates a faultless correlation between protons and adjacent carbons, and no correlation in the case of all quaternary carbons.

scholarly journals A stronger recognizability condition for two-dimensional languages

2013 ◽  
Vol Vol. 15 no. 2 (Automata, Logic and Semantics) ◽  
Author(s):  
Marcella Anselmo ◽  
Maria Madonia
Keyword(s):  
Finite Automata ◽  
The Other ◽  
Two Dimensional ◽  
Minimal Size ◽  
One Dimensional ◽  
Tiling System ◽  
International Audience ◽  
The One

Automata, Logic and Semantics International audience The paper presents a condition necessarily satisfied by (tiling system) recognizable two-dimensional languages. The new recognizability condition is compared with all the other ones known in the literature (namely three conditions), once they are put in a uniform setting: they are stated as bounds on the growth of some complexity functions defined for two-dimensional languages. The gaps between such functions are analyzed and examples are shown that asymptotically separate them. Finally the new recognizability condition results to be the strongest one, while the remaining ones are its particular cases. The problem of deciding whether a two-dimensional language is recognizable is here related to the one of estimating the minimal size of finite automata recognizing a sequence of (one-dimensional) string languages.

scholarly journals Building Rubiks Cube: A Function Of Production

2008 ◽  
Vol 12 (1) ◽  
pp. 25-32
Author(s):  
Jose Villacis Gonzalez
Keyword(s):  
The Other ◽  
Two Dimensional ◽  
3 Dimensional ◽  
Production Processes ◽  
Key Factor ◽  
Final Design ◽  
Dimensional Cube ◽  
The One ◽  
The Cost ◽  
The Relationship

The Rubiks cube is a special game and a very particular puzzle. The 3-dimensional cube is made up of six faces, or boundary sections, of the same size. Each face, or section, consists of several two dimensional square parts, or cubelets. Every cubelet has the same surface area, and each of the six faces has the same number of cubelets. Therefore, the cubes surface is entirely covered with isocubelets. The cubelets are painted in six different colours, and it is possible to create a design where each face shows only one colour. Such is the object of the game: to turn the cubelets and sections of the cube so that only one (different) colour shows on each one of the six faces. If one manages to master the puzzle, the cube will show six faces of the same size, each coloured differently. The cubelets and sections of the cube can be turned both horizontally and vertically in order to change colours while trying to determine the appropriate combination to complete the puzzle. This approach is linked to a particular function in microeconomics that deals with the relationship between two magnitudes: on the one hand, the moves needed to achieve the desired final design; and on the other hand, the cost linked to the required production processes. This analytical model must use combinatorial mathematics equipment because, after all, the key factor in solving the Rubiks cube is the way in which the cubelets and sections are arranged.

The Relationship between Legality and Legitimacy: A Double-Edged Sword

2019 ◽  
pp. 302-310
Author(s):  
Dana Burchardt
Keyword(s):  
The Other ◽  
Two Dimensional ◽  
Legal Norms ◽  
Other Hand ◽  
Norm Theory ◽  
The One ◽  
The Relationship

This comment on Thilo Marauhn’s chapter addresses the relationship between legality and legitimacy from a norm-related perspective. It inquires into the reasons for the two-dimensional relationship between legality and legitimacy through the lens of norm theory. It considers legal norms on the one hand and legitimacy norms on the other hand, interrogating how these different kinds of norms can coexist, interrelate, and influence each other and what functions they can fulfil in the international sphere. By doing so, it highlights to what extent legal norms and legitimacy norms compete and complement each other—where the double-edged sword in the relationship between legality and legitimacy can be used for undercutting or rather for defending each other.

ENTANGLEMENT, PURITY AND VIOLATION OF BELL INEQUALITY

2009 ◽  
Vol 07 (07) ◽  
pp. 1313-1320 ◽  
Author(s):  
DONG-LING DENG ◽  
JING-LING CHEN
Keyword(s):  
Bell Inequality ◽  
The Other ◽  
Two Dimensional ◽  
Entanglement Of Formation ◽  
Other Hand ◽  
Chsh Inequality ◽  
The One ◽  
The Relationship ◽  
Qubit States

We use the Clauser–Horne–Shimony-Holt (CHSH) inequality to investigate the relationship among entanglement, purity and violation of the Bell inequality. On the one hand, we show numerically that all two-dimensional (qubit) states, whose entanglement of formation (EOF) is larger than [Formula: see text], violate the CHSH inequality. On the other hand, any state with purity smaller than 0.5562 may not violate it.

Crystal engineering using bisphenols: interwoven ladders, sheet and framework structures in the binary adducts of 4,4′-sulfonyldiphenol with pyrazine (2/1), 4,4′-bipyridyl (1/1), trans-1,2-bis(4-pyridyl)ethene (1/1), 1,2-bis(4-pyridyl)ethane (1/1) and 4,4′-trimethylenedipyridine (1/1), and in 4,4′-sulfonyldiphenol–4,4′-trimethylenedipiperidine–water (2/2/1)

1999 ◽  
Vol 55 (4) ◽  
pp. 573-590 ◽  
Author(s):  
George Ferguson ◽  
Christopher Glidewell ◽  
Richard M. Gregson ◽  
Emma S. Lavender
Keyword(s):  
Hydrogen Bonds ◽  
Crystal Engineering ◽  
Three Dimensional ◽  
The Other ◽  
Single Type ◽  
Water Molecules ◽  
Two Dimensional ◽  
Double Helices ◽  
The One ◽  
N Vector

The structures of six hydrogen-bonded adducts of 4,4′-sulfonyldiphenol with heteroaromatic amines have been determined. In 4,4′-sulfonyldiphenol–pyrazine (2/1) the pyrazine molecules lie across centres of inversion. The bisphenol molecules are linked into C(8) chains parallel to [100] by means of O—H...O=S hydrogen bonds, and antiparallel pairs of these chains are cross-linked by the pyrazine molecules, via O—H...N hydrogen bonds, to form molecular ladders containing R_6^6(50) rings between the rungs of the ladders. Each ladder is interwoven with two neighbouring ladders, thus producing a continuous two-dimensional sheet. The structure of 4,4′-sulfonyldiphenol–4,4′-bipyridyl (1/1) consists of spiral C_2^2(21) chains parallel to [010] containing alternating bisphenol and bipyridyl molecules linked by O—H...N hydrogen bonds: these chains are linked by two types of C—H...O hydrogen bonds which form C(5) chains along [001] and C_2^2(10) chains along [101], thus generating two interconnected nets characterized in the one case by a chequerboard pattern of R_6^6(44) and R_6^6(52) rings, and in the other by a single type of R_6^6(46) ring. 4,4′-Sulfonyldiphenol–trans-1,2-bis(4-pyridyl)ethene (1/1) [systematic name: 4,4′-sulfonyldiphenol–trans-4,4′-vinylenedipyridine (1/1)] and 4,4′-sulfonyldiphenol–1,2-bis(4-pyridyl)ethane (1/1) [systematic name: 4,4′-sulfonyldiphenol–trans-4,4′-ethylenedipyridine (1/1)] are isomorphous: the 1,2-bis(4-pyridyl)ethene component exhibits orientational disorder, corresponding approximately to a 180° rotation of ca 23% of the molecules about the N...N vector; in each compound the structure is built from C_2^2(23) chains of alternating bisphenol and bis(pyridyl) molecules connected by O—H...N hydrogen bonds, running parallel to [112] and generated by translation. The [112] chains are linked by C—H...O hydrogen bonds which generate C_2^2(12) chains parallel to [101], so forming a two-dimensional net built from R_6^6(50) rings. The structure of 4,4′-sulfonyldiphenol–4,4′-trimethylenedipyridine (1/1) consists of C_2^2(24) chains parallel to [100] generated by translation and consisting of alternating bisphenol and bis(pyridyl) molecules linked by O—H...N hydrogen bonds. Pairs of such chains are coiled together to form double helices, and pairs of such double helices, of opposite hand, are linked together by paired C—H...O hydrogen bonds in R_2^2(10) rings to form pairs of interwoven ladders in which the C_2^2(24) chains form the uprights and the R_2^2(10) rings form the rungs, between which are R_6^6(50) rings: an R_2^2(10) ring belonging to one ladder lies at the centre of an R_6^6(50) ring belonging to the other. 4,4′-Sulfonyldiphenol–4,4′-trimethylenedipiperidine–water (2/2/1) is a salt, 2C13H27N_2^+·2C12H9O4S−·H2O, containing two independent singly protonated diamine cations, two independent bisphenolate anions, and neutral water molecules. The two independent diamine cations are linked by N—H...N hydrogen bonds into C_2^2(24) chains running parallel to [001] and generated by translation, and each type of bisphenolate anion forms an independent spiral C(12) chain, also parallel to [001]. The three types of chain are linked by the water molecules: the two types of bisphenolate chain are linked by water molecules acting as double donors in O—H...O− hydrogen bonds in a C_6^4(32) chain parallel to [100], thus generating a two-dimensional net built from R_8^6(56) rings; the diamine chains are linked to these nets by means of N—H...O hydrogen bonds in which the water molecules act as acceptors and further hydrogen bonds, of N—H...O− and N—H...O=S types, link these two-dimensional nets into a continuous three-dimensional framework.

The Flight from the Good Life: Fahrenheit 451 in the Context of Postwar American Dystopias

1994 ◽  
Vol 28 (2) ◽  
pp. 225-240
Author(s):  
David Seed
Keyword(s):  
New World ◽  
Good Life ◽  
Seventh Century ◽  
The Other ◽  
The Good Life ◽  
Two Dimensional ◽  
Aldous Huxley ◽  
Brave New World ◽  
Grand Inquisitor ◽  
The One

Surveying the American scene in 1958, Aldous Huxley recorded his dismay over the speed with which Brave New World was becoming realized in contemporary developments: “The nightmare of total organization, which I had situated in the seventh century After Ford, has emerged from the safe, remote future and is now awaiting us, just around the next corner.” Having struck a keynote of urgency Huxley then lines up a series of oppositions between limited disorder, individuality and freedom on the one hand, and order, automatism and subjection on the other in order to express his liberal anxieties that political and social organization might hypertrophy. Huxley sums up an abiding fear which runs through American dystopian fiction of the 1950s that individuals will lose their identity and become the two-dimensional stereotypes indicated in two catch-phrases of the period: the “organization man” and the “man in the grey flannel suit. ” William H. Whyte's 1956 study diagnoses the demise of the Protestant ethic in American life and its replacement by a corporate one which privileges “belongingness. ” The result might be, he warns, not a world controlled by self-evident enemies familiar from Nineteen Eighty-Four, but an antiseptic regime presided over by a “mild-looking group of therapists who, like the Grand Inquisitor, would be doing what they did to help you.”

A note on the optimum profile of a sprayless planing surface

1999 ◽  
Vol 384 ◽  
pp. 281-292 ◽  
Author(s):  
DMITRI V. MAKLAKOV
Keyword(s):  
Water Surface ◽  
Lift Force ◽  
Exact Analytical Solution ◽  
The Other ◽  
Two Dimensional ◽  
End Points ◽  
Spray Formation ◽  
Isoperimetric Constraint ◽  
The One ◽  
Optimum Profile

The paper presents an exact analytical solution to the problem of finding the optimum profile of a two-dimensional plate which planes on a water surface without spray formation and maximizes the lift force. The lift is maximized under the only isoperimetric constraint of fixed total arclength of the plate. The exact solution is compared with approximate analytical and numerical results by Wu & Whitney (1972). The shape of the optimum plate turns out to be technically unrealizable because of small, tightly wound spirals near the end points. It was shown numerically that cutting off small segments near the end points leads on the one hand to insignificant change in the lift force and on the other hand to a non-separating boundary layer along the remaining part of the optimum plate.

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