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Shellac, also known as lac, is composed mainly of aleuritic acid.

A subject of continuous discussion in the field of underwater archaeology is how to safely extract fragile waterlogged artifacts while maintaining their best condition. In this study, lacquerware with fragile wooden body was simulated and extracted, using a triple-package reinforcement technique. Using veratraldehyde as a temporary consolidant, SH-MWCNTs@PU sponge/epoxy resin composite materials as free-form reinforced layers, and double-sided self-adhesive bandages wrapped around the outer layer, the safe underwater extraction and the layer-by-layer removal of the simulated artifacts were studied. The method maximized the preservation of the artifacts’ state and information and minimized their damage during removal and transport. This method can be used as a technique for the extraction of fragile artifacts from underwater archaeological excavation sites.

Three new crystal structures containing [PtCl6]2&minus, pyridinium and benzimidazole groups have been prepared: [PtCl6]&middot, (H-bzm)2&middot, 2(H2O) (1), [PtCl6]&middot, (H-bipy)2&middot, 2(H2O) (2), [PtCl6]&middot, (H-dimethyl-bipy)2&middot, 2(H2O) (3) [H-bzm: benzimidazole cation, H-bipy: 2,2&prime, bipyridine cation, H-dimethyl-bipy: 4,4&prime, bimethyl-2,2&prime, bipyridine cation]. All compounds have been fully characterized by elemental analyses, single-crystal X-ray analyses, IR spectra, TG analyses, and fluorescence studies. Single-crystal X-ray diffraction analysis suggests that the primary synthon contains +N&ndash, H&middot, &middot, Cl&minus, including ionic bonding and hydrogen bonding interactions. The dimensions are enhanced further by secondary O&ndash, H ∙∙Cl and N&ndash, H ∙∙O hydrogen bonding interactions between donor and acceptor atoms located at the periphery of these synthons. Moreover, coulombic attractions between the ions play an important role in reinforcing the structures of these complexes. In addition, antitumor activity against human lung adenocarcinoma cell line (A549) and human nasopharyngeal carcinoma cell line (CNE-2) was performed. These complexes all showed inhibition to the two cell lines, while complex 3 exhibited higher efficiency than complexes 1&ndash, 2.

In the solvothermal condition, a Pd(II) complex with a in situ synthesis ligand, [Pd(2,2’-bipy)2(CN)2] (1) was obtained and characterized by elemental analysis, IR, UV, TG, and powder X-ray analysis. The single crystal X-ray analysis showed that the title complex is different from the reported 2,2’-bipyridyl-dicyanopalladium(II) (2) in crystal system and structural parameters. The catalytic investigation for the reactions of the disproportionation of hydrogen peroxide and oxidation of sulfide showed that the complex 1 is an active homogeneous catalyst in the presence of imidazole and 2-sulfobenzoic acid, respectively.

The structural properties of a new copper (II) complex [Cu2(cip)2(bpy)2(pip)]·6H2O (bpy=2,2’-bipyridyl, cip=1-cyclopropyl-6-4-oxo-1,4-dihydroquinoline-3-carboxylic acid, pip= piperazinyl anion), obtained during the synthesis of the copper complex with ciprofloxacin (cpf), has been investigated. The complex crystallizes in the triclinic system, space group P-1. The cell dimensions are: a=6.874(2) Å, b= 10.761(3) Å, c= 17.969(5) Å, α =80.071(6)°, β= 85.253(6)°, γ=79.109(6)°，V=1284.5(6) Å3, and Z=2. The Cu (II) ion displays a five-coordinate square pyramidal coordination with two nitrogen donors from bpy, the 4-keto and 3-carboxylate oxygen donors of cip, and the third nitrogen atom of the pip anion occupying the fifth site. There is a stack effect between cip ring and bpy ring from another molecule, where the stacking distance is about 3.5 Å. The results of elemental analysis and FT-IR measurement are also included. Both ligand and complex were assayed against gram-positive and gram-negative bacteria by the doubling dilutions method. The complex shows the same minimal inhibitory concentration (MIC) against S. Aureus and E. Coli bacteria as the corresponding ligand.

By modifying the delta values of molecular connectivity indexes, new quantum-topology descriptors are presented in this paper. Their ability to describe molecular structure, both geometric and electronic, is established by correlating them with the bonding energy (E), force constant (kappa), and radius (R) of a heterogeneous set of monohydrides, as well as with the solubility in water -log S, hydrophobic constants -log P, and molecular volumes of halogenobenzenes and the standard heat of formation of SiXn (n = 1-4, X = F, Cl, Br, I). Moreover, it is clearly demonstrated that this ability is greater than that shown by the chi connectivity indexes.

Aryl halides were prepared by condensation of 2-methylquinoline and bromo- or chloro-arylaldehydes in acetic anhydride. Diarylamines reacted with the aryl halides to afford novel triarylamine derivatives using Pd(OAc)2/P ( o-tolyl)3 as catalyst. These compounds have potential as organic light-emitting device materials and were characterised by FT-IR, 1H NMR and elemental analyses. The UV-vis absorption and photoluminescent spectra of the compounds in CH2CI2 were investigated. The lowest absorption band of the triarylamine derivatives centred at about 400 nm was assigned to a charge-transfer transition with an emission at 500–515 nm.

Aryl halides were prepared by condensation of 2-methylquinoline and bromo- or chloro-arylaldehydes in acetic anhydride. Diarylamines reacted with the aryl halides to afford novel triarylamine derivatives using Pd(OAc) 2/ P (o-tolyl) 3 as catalyst. These compounds have potential as organic light-emitting device materials and were characterised by FT-IR, 1 H NMR and elemental analyses. The UV-vis absorption and photoluminescent spectra of the compounds in CH 2 Cl 2 were investigated. The lowest absorption band of the triarylamine derivatives centred at about 400 nm was assigned to a charge-transfer transition with an emission at 500―515 nm.