1,748 research outputs found
Creatinium hydrogen oxalate
The crystal structure of the title compound, C4H10N3O2
+·C2HO4
−, is stabilized by N—H⋯O and O—H⋯O hydrogen bonds. The anions are connected by an O—H⋯O hydrogen bond, leading to C(5) chain extending along c axis. The cations are dimerized around the corners of the unit cell, leading to an R
2
2(14) ring motif. This leads to a cationic molecular aggregation at x = 0 or 1 and an anionic molecular aggregation at x = 1/2
Creatininium cinnamate
The crystal structure of the title compound (systematic name: 2-amino-1-methyl-4-oxo-4,5-dihydro-1H-imidazol-3-ium 3-phenylprop-2-enoate), C4H8N3O+·C9H7O2
−, is stabilized by N—H⋯O hydrogen bonding. Cations are linked to anions to form ion pairs with an R
2
2(8) ring motif. These ion pairs are connected through a C
2
2(6) chain motif extending along the c axis of the unit cell. This crystal packing is characterized by hydrophobic layers at x ∼ 1/2 packed between hydrophilic layers at x ∼ 0
Creatininium 2-chloroacetate
In the title compound (systematic name: 2-amino-1-methyl-4-oxo-4,5-dihydro-1H-imidazol-3-ium 2-chloroacetate), C4H8N3O+·C2H2ClO2
−, the molecular aggregations are stabilized through classical (N—H⋯O) and non-classical (C—H⋯O and C—H⋯N) hydrogen-bonding interactions. The cations are linked to the anions, forming ion pairs through two N—H⋯O bonds that produce characteristic R
2
2(8) ring motifs. These cation–anion pairs are connected through another N—H⋯O hydrogen bond, leading to an R
4
2(8) ring motif. Further weak C—H⋯N interactions link the molecules along the a axis, while other C—H⋯O interactions generate zigzag chains extending along b
Preparation and Study of Charge Transfer Complexes of N.N.N.N-Tetra-Methyl-Para-Phenylene-Diamine (TMPD) with NG, Tetryl, RDX and HMX
Charge transfer complexes of NG tetryl, RDX and HMX as electron acceptors with tetra-methyl-para-phenylene-diamine (TMPD) as electron donor were prepared and studied. When the solution of nitro-explosives in an inert solvent were added to a solution of TMPD, an intense violet colour was produced. This colour is due to the formation of TMPD cation known as Wurster radical formed from TMPD through the loss of an electron. It has been shown that one mole of each of NG, tetryl, RDX and HMX is needed to form oneTMPD cation. These complexes have also been studied by ultra-violet and infrared spectroscopy
A triclinic polymorph of 3-nitroanilinium chloride
The asymmetric unit of the title compound, C6H7N2O2
+·Cl−, contains two independent ion pairs. A monoclinic form of the title compound with only one ion pair in the asymmetric unit has been reported previously [Ploug-Sørensen & Andersen (1986). Acta Cryst. C42, 1813–1815]. In the crystal of the title compound, the components are linked into layers parallel to (001) by intermolecular N—H⋯Cl hydrogen bonds, with alternating hydrophilic and hydrophobic regions
Large deviations of the sample mean in general vector spaces
Let X1, X2, ··· be a sequence of i.i.d. random vectors taking values in a space V, let X-n = (X1 + ··· + Xn)/n, and for J ⊂ V let an(J) = n-1log P(X-n∈ J). A powerful theory concerning the existence and value of limn→∞ an(J) has been developed by Lanford for the case when V is finite-dimensional and X1 is bounded. The present paper is both an exposition of Lanford's theory and an extension of it to the general case. A number of examples are considered; these include the cases when X1 is a Brownian motion or Brownian bridge on the real line, and the case when X-n is the empirical distribution function based on the first n values in an i.i.d. sequence of random variables (the Sanov problem)
Creatininium hydrogen maleate
In the title compound, C4H8N3O+·C4H3O4
−, the cations and anions are linked through N—H⋯O hydrogen bonds making a ionic pair with an R
2
2(8) ring motif. These ionic pairs are further connected through another N—H⋯O hydrogen bond, leading to an R
6
6(16) ring motif around the inversion centres of the unit cell. These approximately planar aggregates are further connected through weak van der Waals interactions in the unit cell. The anions have a characteristic intramolecular O—H⋯O hydrogen bond with a self-associated ring S(7) motif
The statistical strength of experiments to reject local realism with photon pairs and inefficient detectors
Because of the fundamental importance of Bell's theorem, a loophole-free
demonstration of a violation of local realism (LR) is highly desirable. Here,
we study violations of LR involving photon pairs. We quantify the experimental
evidence against LR by using measures of statistical strength related to the
Kullback-Leibler (KL) divergence, as suggested by van Dam et al. [W. van Dam,
R. Gill and P. Grunwald, IEEE Trans. Inf. Theory. 51, 2812 (2005)].
Specifically, we analyze a test of LR with entangled states created from two
independent polarized photons passing through a polarizing beam splitter. We
numerically study the detection efficiency required to achieve a specified
statistical strength for the rejection of LR depending on whether photon
counters or detectors are used. Based on our results, we find that a test of LR
free of the detection loophole requires photon counters with efficiencies of at
least 89.71%, or photon detectors with efficiencies of at least 91.11%. For
comparison, we also perform this analysis with ideal unbalanced Bell states,
which are known to allow rejection of LR with detector efficiencies above 2/3.Comment: 18 pages, 3 figures, minor changes (add more references, replace the
old plots, etc.)
Allocative Efficiency of Resource use on Beekeeping in Chitwan District of Nepal
Agriculture is facing with increasing pollinators decline all over the world affecting the functioning of regulatory and production service of pollination in adverse manner. Study on ways to conserve pollinating agents like bee is crucial in modern intensive agriculture. In this context a study was conducted to estimate the productivity and resource use efficiency of bee keeping in Chitwan district of Nepal. The study used data collected from randomly selected 48 bee keepers using face to face interview technique in the year 2014. Descriptive statistics, gross margin analysis, benefit cost analysis and multiple regression analysis using Cob-Douglas form were employed to achieve study objectives. It was found that farmers were rearing honey bee on an average of about 34 hives per farm with annual productivity of bee products equivalent to 36 Kg honey per hive. Gross margin of beekeeping in the research area was found to be NRs. 3111.55 per hive with undiscounted benefit cost ratio of 1.71. Human labour use, expenditure on sugar, drugs and comb foundation and; migration cost were significantly contributing to the productivity of beekeeping and were required to increase their use by 39%, 34% and 74%, respectively to achieve optimum profit. It was suggested to increase the level of all variable inputs through loan, subsidy and insurance to promote beekeeping enterprise in the study area for ensuring optimum profit to farmers and conservation of the most important agent of pollination
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