Strengthening measurements from the edges: application-level packet loss rate estimation

Network users know much less than ISPs, Internet exchanges and content providers about what happens inside the network. Consequently users cannot either easily detect network neutrality violations or readily exercise their market power by knowledgeably switching ISPs. This paper contributes to the ongoing efforts to empower users by proposing two models to estimate -- via application-level measurements -- a key network indicator, i.e., the packet loss rate (PLR) experienced by FTP-like TCP downloads. Controlled, testbed, and large-scale experiments show that the Inverse Mathis model is simpler and more consistent across the whole PLR range, but less accurate than the more advanced Likely Rexmit model for landline connections and moderate PL

2-(Phenyl­carbonothio­ylsulfan­yl)acetic acid

The title compound, C9H8O2S2, can be used as a chain transfer agent and may be used to control the behavior of polymerization reactions. O—H⋯O hydrogen bonds of moderate character link the mol­ecules into dimers. In the crystal, the dimers are linked into sheets by C—H⋯O inter­actions, forming R 4 2(12) and R 2 2(8) edge-fused rings running parallel to [101]. There are no inter­molecular inter­actions involving the S atoms

3-(2,4-Dibromo­anilino)-2,2-dimethyl-2,3-dihydro­naphtho[1,2-b]furan-4,5-dione: a new substituted aryl­amino nor-β-lapachone derivative

The title compound, C20H15Br2NO3, shows the furan ring to adopt a half-chair conformation and the two ring systems to be approximately perpendicular [dihedral angle = 71.0 (2)°]. In the crystal structure, inter­molecular C—H⋯O contacts link the mol­ecules

4-Methyl­phenyl 4-bromo­benzoate

In the title compound, C14H11BrO2, an ester formed from the reaction of 4-methyl­phenol with 4-bromo­benzoyl­chloride, the dihedral angle between the benzene rings is 54.43 (7)°, indicating a twist in the mol­ecule. In the crystal, weak C—H⋯O inter­actions link the mol­ecules into supra­molecular layers in the bc plane, and these are connected along the a axis by Br⋯Br contacts [3.6328 (5) Å]

trans-5,6-Diphenyl­perhydro­pyran-2,4-dione

In the title compound, C17H14O3, the pyran ring adopts a boat conformation and the dihedral angle between the aromatic ring planes is 59.1 (1)°. In the crystal structure inter­molecular C—H⋯O hydrogen bonds and C—H⋯π inter­actions link the mol­ecules

1-(4-Bromo­phen­yl)-2-ethyl­sulfinyl-2-(phenyl­selan­yl)ethanone monohydrate

In the title hydrate, C16H15BrO2SSe·H2O, the sulfinyl O atom lies on the opposite side of the mol­ecule to the Se and carbonyl O atoms. The benzene rings form a dihedral angle of 51.66 (17)° and are splayed with respect to each other. The observed conformation allows the water mol­ecules to bridge sulfinyl O atoms via O—H⋯O hydrogen bonds, generating a linear supra­molecular chain along the b axis; the chain is further stabilized by C—H⋯O contacts. The chains are held in place in the crystal structure by C⋯H⋯π and C—Br⋯π inter­actions

2-(4-Methyl­phen­yl)-1H-anthraceno[1,2-d]imidazole-6,11-dione: a fluorescent chemosensor

In the title compound, C22H14N2O2, the five rings of the mol­ecule are not coplanar. There is a significant twist between the four fused rings, which have a slightly arched conformation, and the pendant aromatic ring, as seen in the dihedral angle of 13.16 (8)° between the anthraquinonic ring system and the pendant aromatic ring plane

cis-Bis[1,1-dibenzyl-3-(furan-2-yl­carbonyl)thio­ureato-κ2 O,S]copper(II)

In the title compound, [Cu(C20H17N2O2S)2], the CuII atom is coordinated by the S and O atoms of two 1,1-dibenzyl-3-(furan-2-ylcarbon­yl)thio­ureate ligands in a distorted square-planar geometry. The two O and two S atoms are mutually cis to each other. The Cu—S and Cu—O bond lengths lie within the ranges of those found in related structures. The dihedral angle between the planes of the two chelating rings is 26.15 (6)°

Conventional and microwave-assisted reaction of N-hydroxymethylphthalimide with arylamines: synthesis of N-(arylaminomethyl)-phthalimides

An efficient and easy synthesis of compounds: 2-Phenylaminomethyl-isoindole-1,3-dione (5a), 2-[(2-Clorophenylamino)methyl]-isoindole-1,3-dione (5b), 2-[(3-Clorophenylamino)methyl]-isoindole-1,3-dione (5c), 2-[(4-Clorophenylamino)methyl)-isoindole-1,3-dione (5d), 2-[(2-Fluorophenylamino)methyl]-isoindole-1,3-dione (5e), 2-[(3-fluorophenylamino)methyl]-isoindole-1,3-dione (5f), 2-[(4-Fluorophenylamino)methyl]-isoindole-1,3-dione (5g), 2-[(2-Nitrophenylamino)methyl]-isoindole-1,3-dione (5h), 2-[(3-Nitrophenylamino)methyl]-isoindole-1,3-dione (5i), 2-[(4-Nitrophenylamino)methyl]-isoindole-1,3-dione (5j), 2-[1H-(1,2,4)Triazol-3-yl-aminomethyl)-isoindole-1,3-dione (5k) and 2-([1,2,4]-Triazole-4-yl-aminomethyl)-isoindole-1,3-dione (5l), is described. The general synthesis procedure starts from N-hydroxymethylphthalimide 3 and aryl- and [1,2,4-triazol-3- and 4-yl]-amines 4a-l by conventional and solvent-free microwave-mediated. The reaction of 3 with 4l turned out to be a very rapid and high-yielding one. A comparison of these two methods has been made. Three probable mechanisms of formation of N-(arylaminomethyl)-phthalimides (one in the solution phase and two in the microwave-accelerated conditions are proposed. Crystallographic analyses of 5d furnished the correct conformation of this molecule. Ab initio molecular orbital calculations of 5d using 6-31G* basis set were performed and the results were comparable to the X-ray data