3,945 research outputs found
2-(m-Tolyloxy)benzoic acid
In the crystal structure of the title compound, C14H12O3, the molecules form classical O—H⋯O hydrogen-bonded carboxylic acid dimers. The dihedral angle between the two rings is 80.9 (3)°
Bis(μ2-2-chlorobenzoato-κ2 O:O′)bis[(2-chlorobenzoato-κO)(1,10-phenanthroline-κ2 N:N′)copper(II)] dihydrate
In the title compound, [Cu2(C7H4ClO2)4(C12H8N2)2]·2H2O, the two crystallographically independent dinuclear complex molecules, A and B, have different Cu⋯Cu separations, viz. 3.286 (1) Å in A and 3.451 (1) Å in B. Both independent molecules reside on inversion centres, so the asymmetric unit contains a half-molecule each of A and B and two water molecules. Each Cu atom has a square-pyramidal environment, being coordinated by two O atoms from two bridging 2-chlorobenzoate ligands, one O atom from a monodentate 2-chlorobenzoate ligand and two N atoms from a 1,10-phenanthroline ligand. The water molecules can also be considered as coordinating ligands, which complete the coordination geometry up to distorted octahedral with elongated Cu—O distances, viz. 3.024 (3) Å in A and 2.917 (3) Å in B. In the crystal, weak intermolecular C—H⋯O interactions contribute to the consolidation of the crystal packing
Diethyl 2-{[(4-methoxy-3-pyridyl)amino]methylidene}malonate
In the title molecule, C14H8N2O5, the amino group is involved in the formation an intramolecular N—H⋯O hydrogen bond. In the crystal, weak intermolecular C—H⋯O and C—H⋯N hydrogen bonds link the molecules into ribbons along the b axis
Efficacy and Safety of Ribavirin with Sofosbuvir Plus Ledipasvir in Patients with Genotype 1 Hepatitis C: A Meta-Analysis
Does global value chain engagement improve export quality? Evidence from Chinese manufacturing firms
Using a firm-level data set of Chinese manufacturing sector, we
examine whether global value chain (G.V.C.) engagement induces
firms to upgrade the quality of the goods that they export.
Empirical results show that G.V.C. participation has positive impact
on export product quality, and this finding is consistent across
several robustness checks. However, the influence of G.V.C.
embedment on export quality presents an ‘inverted-U’ shape. The
mechanism analysis demonstrates that the effect of G.V.C. participation
on export quality is driven by competition effect and firms’
willingness to import high-quality intermediates. Furthermore, the
quality effect of G.V.C. embedment differs depending on firm
characteristics. This article therefore contributes to a better understanding
of the benefits of participation in G.V.C.s for manufacturing
firms from developing countries
A SiO J = 5 - 4 Survey Toward Massive Star Formation Regions
We performed a survey in the SiO line toward a sample of
199 Galactic massive star-forming regions at different evolutionary stages with
the SMT 10 m and CSO 10.4 m telescopes. The sample consists of 44 infrared dark
clouds (IRDCs), 86 protostellar candidates, and 69 young \HII\ regions. We
detected SiO line emission in 102 sources, with a detection
rate of 57\%, 37\%, and 65\% for IRDCs, protostellar candidates, and young
\HII\ regions, respectively. We find both broad line with Full Widths at Zero
Power (FWZP) 20 \kms and narrow line emissons of SiO in objects at various
evolutionary stages, likely associated with high-velocity shocks and
low-velocity shocks, respectively. The SiO luminosities do not show apparent
differences among various evolutionary stages in our sample. We find no
correlation between the SiO abundance and the luminosity-to-mass ratio,
indicating that the SiO abundance does not vary significantly in regions at
different evolutionary stages of star formation.Comment: 25 pages, 9 figures, 5 tables, accepted for publication in Ap
Excited Heavy Quarkonium Production at the LHC through -Boson Decays
Sizable amount of heavy-quarkonium events can be produced through -boson
decays at the LHC. Such channels will provide a suitable platform to study the
heavy-quarkonium properties. The "improved trace technology", which disposes
the amplitude at the amplitude-level, is helpful for deriving
compact analytical results for complex processes. As an important new
application, in addition to the production of the lower-level Fock states
and , we make a further study on the
production of higher-excited -quarkonium Fock states
, and . Here
stands for the -charmonium,
-quarkonium and -bottomonium respectively. We show
that sizable amount of events for those higher-excited states can also be
produced at the LHC. Therefore, we need to take them into consideration for a
sound estimation.Comment: 7 pages, 9 figures and 6 tables. Typo errors are corrected, more
discussions and two new figures have been adde
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