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In the quest for optimal H 2 evolution (HE) through ethanol photoreforming, a dual cocatalyst-modified heterocatalyst strategy is utilized. Tin(II) sulfide (SnS) was hybridized with α-Fe 2 O 3 to form the heterocatalyst FeOSnS with a p-n heterojunction structure as confirmed by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), UV-vis diffusive reflectance spectroscopy (UV-vis DRS), and Brunauer-Emmett-Teller (BET) techniques. PdO x and PdO x /MnO x cocatalysts were loaded onto the FeOSnS heterocatalyst through the impregnation method, as verified by high-resolution transform electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), and elemental mapping. Photocatalytic ethanol photoreforming resulted in the production of H 2 as the main product with a selectivity of 99% and some trace amounts of CH 4 . The FeOSnS2-PdO x 2%/MnO x 1% photocatalyst achieved the highest HE rate of 1654 μmol/g, attributed to the synergistic redox contribution of the PdO x and MnO x species., Competing Interests: The authors declare no competing financial interest., (© 2022 The Authors. Published by American Chemical Society.)

Inspired by the crystal structure of a Mn III dinuclear complex we obtained featuring both Jahn-Teller (JT) elongation and compression distortions, we have modelled a series of complex cations based on the disordered crystal formulation; [Mn 2 (L1) 2 (μ 2 -OH) 2 ) 4+ (1), [Mn 2 (L1)(L2)(μ 2 -OH) 2 ) 4+ (2), [Mn 2 (L2)(L1)(μ 2 -OH) 2 ) 4+ (3), and [Mn 2 (L2) 2 (μ 2 -OH) 2 ) 4+ (4) (where L1 = (1 E ,1' E )-5- tert -butyl-3-(((4-(((5- tert -butyl-2-hydroxy-3-(( E )-(hydroxyimino)methyl)benzyl)(methyl)amino)methyl)benzyl)(methyl)amino)methyl)-2-hydroxybenzaldehyde and L2 = 3,3'-(1,4-phenylenebis(methylene))bis(methylazanediyl)bis(methylene)bis(5- tert -butyl-2-hydroxybenzaldehyde)) with different geometries to investigate the effects of the distortions on the magnetic coupling parameter. All computationally modelled dimers had a ferromagnetic interaction between the Mn III centres, with greater magnetic coupling calculated for complexes with both JT elongation and compression present. The ferromagnetic contribution to the J coupling was ascribed to the orthogonality of the singly occupied magnetic orbitals along with the cross-interaction between the unfilled Mn1(d x 2 - y 2 ) and singly occupied Mn2(d x 2 - y 2 ) orbitals. Constrained calculations showed that reducing the extent of the compression at Mn2 results in a concomitant increase in the dihedral angle between the JT axes, thereby reducing the relative magnitude of the magnetic coupling between Mn III centres.

Iron oxide nanoparticles (IONPs) have gained increasing attention in various biomedical and industrial sectors due to their physicochemical and magnetic properties. In the biomedical field, IONPs are being developed for enzyme/protein immobilization, magnetofection, cell labeling, DNA detection, and tissue engineering. However, in some established areas, such as magnetic resonance imaging (MRI), magnetic drug targeting (MDT), magnetic fluid hyperthermia (MFH), immunomagnetic separation (IMS), and magnetic particle imaging (MPI), IONPs have crossed from the research bench, received clinical approval, and have been commercialized. Additionally, in industrial sectors IONP-based fluids (ferrofluids) have been marketed in electronic and mechanical devices for some time. This review explores the historical evolution of IONPs to their current state in biomedical and industrial applications.

We report the synthesis and crystal structure of the first quinolino[7,8- h ]quinoline beryllium(II) complex of the general formula [BeL2(MeCN)Br]Br·MeCN, containing the ligand 4,9-dihydroxyquinolino[7,8- h ]quinoline (L2). The Be(II) cation is a great size match for the dinitrogen binding pocket of the quinolino[7,8- h ]quinoline ligand as indicated by minimal out-of-plane displacement and ligand distortion parameters.

Cu I complexes containing the bulky dialkylbiarylphosphane 2-(di-tert-butylphosphanyl)-2',4',6'-triisopropylbiphenyl ( t BuXPhos, L) and an ancillary ligand (Cl - , Br - , I - , MeCN, ClO 4 - or SCN - ) have been structurally characterized, namely, chlorido[2-(di-tert-butylphosphanyl)-2',4',6'-triisopropylbiphenyl-κP]copper(I), [CuCl(C 29 H 45 P)], 1, bromido[2-(di-tert-butylphosphanyl)-2',4',6'-triisopropylbiphenyl-κP]copper(I), [CuBr(C 29 H 45 P)], 2, [2-(di-tert-butylphosphanyl)-2',4',6'-triisopropylbiphenyl-κP]iodidocopper(I), [CuI(C 29 H 45 P)], 3, (acetonitrile-κN)[2-(di-tert-butylphosphanyl)-2',4',6'-triisopropylbiphenyl-κP]copper(I) hexafluoridophosphate, [Cu(CH 3 CN)(C 29 H 45 P)]PF 6 , 4, [2-(di-tert-butylphosphanyl)-2',4',6'-triisopropylbiphenyl-κP](perchlorato-κO)copper(I), [Cu(ClO 4 )(C 29 H 45 P)], 5, and di-μ-thiocyanato-κ 2 S:N;κ 2 N:S-bis{[2-(di-tert-butylphosphanyl)-2',4',6'-triisopropylbiphenyl-κP]copper(I)}, [Cu 2 (NCS) 2 (C 29 H 45 P) 2 ], 6. Iodide complex 3 shows significant Cu I -arene interactions, in contrast to its chloride 1 and bromide 2 counterparts, which is attributed to the weaker interaction between the iodide ion and the Cu I centre. When replacing iodide with an acetonitrile (in 4) or perchlorate (in 5) ligand, the reduced interaction between the Cu I atom and the ancillary ligand results in stronger Cu I -arene interactions. No Cu I -arene interactions are observed in dimer 6, due to the tricoordinated Cu I centre having sufficient electron density from the coordinated ligands.

Quinolino[7,8- h ]quinoline is a superbasic compound, with a p K aH in acetonitrile greater than that of 1,8-bis(dimethylaminonaphthalene) (DMAN), although its synthesis and the synthesis of its derivatives can be problematic. The use of halogen derivatives 4,9-dichloroquinolino[7,8- h ]quinoline ( 16 ) and 4,9-dibromoquinolino[7,8- h ]quinoline ( 17 ) as precursors has granted the formation of a range of substituted quinolinoquinolines. The basicity and other properties of quinolinoquinolines can be modified by the inclusion of suitable functionalities. The experimentally obtained p K aH values of quinolino[7,8- h ]quinoline derivatives show that N 4 , N 4 , N 9 , N 9 -tetraethylquinolino[7,8- h ]quinoline-4,9-diamine ( 26 ) is more superbasic than quinolino[7,8- h ]quinoline. Computationally derived p K aH values of quinolinoquinolines functionalized with dimethylamino (NMe 2 ), 1,1,3,3-tetramethylguanidino (N═C(NMe 2 ) 2 ) or N , N , N ', N ', N ″, N ″-hexamethylphosphorimidic triamido (N═P(NMe 2 ) 3 ) groups are significantly greater than those of quinolino[7,8- h ]quinoline. Overall, electron-donating functionalities are observed to increase the basicity of the quinolinoquinoline moiety, while the substitution of electron-withdrawing groups lowers the basicity.

Assessment of DNA repair in cultured human fibroblasts by autoradiography may be facilitated by using semiautomated grain counting instruments. The instrument-determined number of autoradiographic grains per nucleus in cultured human skin fibroblasts was found to be linear in comparison to visual counts up to only 30 grains per nucleus. However, with two different instruments a greater range of linearity (to 100 to 120 grains per nucleus) was attained by measuring the grain surface area per nucleus. Semiautomated analysis of the grain surface area per nucleus yielded measurements of relative rates of unscheduled DNA synthesis after ultraviolet irradiation in xeroderma pigmentosum and normal human fibroblasts, which were reproducible and rapid.

Survival of cells in suspension culture after treatment with damaging agents is usually measured by extrapolation from growth curves or by growth of colonies in soft agar. We have developed a survival assay which measures the ability of small numbers of cells to initiate microscopic cultures in wells of microtiter plates without agar or feeder layers. Suitable human lymphoblastoid lines were obtained by selection of rapidly growing cultures from microtiter wells in which < 200 cells were inoculated in 0.2 ml RPMI 1640 medium and incubated at 37 degrees with 5% CO2 at 95% relative humidity. Survival after damage was measured by inoculating groups of 24 microtiter wells with appropriate serial dilutions of cells. The wells were examined microscopically at intervals and scored for evidence of cell proliferation. Survival was calculated with the Poisson formula on the basis of the fraction of wells in which cells were not proliferating. Survival did not change appreciably after 2--3 weeks incubation. Survival measured by the microtiter-well assay was found to be similar to survival measured by extrapolation from growth curves after damaging the cells with bleomycin or with 8-methoxypsoralen plus long-wavelength ultraviolet radiation. The microtiter-well assay affords a simple, accurate measure of cell survival in human lymphoblastoid cells with suitable growth ability.