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Three new complexes derived from 2-(4-(pyridin-2-yl)piperazin-1-yl)acetic acid (HL), [M(L)2(H2O)2] where M = CuII (1), ZnII (2) and CdII (3), have been synthesized and characterized by IR spectroscopy, elemental analysis and X-ray crystallography. The inhibitory activity of these three complexes against MAO-B was tested in vitro, and the molecular docking experiments were also carried out to rationalize their binding models. Both the experimental and docking simulation results indicated that complex 1 has the best inhibitory activity with IC50 value being 6.5 ± 0.31 μM.

Two novel mononuclear complexes, [Cu(L)2(H2O)]·2H2O (1) and [Ni(L)2(H2O)2] (2) (HL = 2-[4-(4-fluorophenyl)piperazin-1-yl]acetic acid) were synthesized and structurally determined by single-crystal X-ray diffraction. Their inhibitory activities were tested in vitro against jack bean urease. Molecular docking was investigated to determine the probable binding mode. The experimental values and docking simulation exhibited that complex 1 had better inhibitory activity than the positive reference aceto hydroxamic acid (AHA), showing IC50 value of 0.15±0.08 µM, while 2 showed no inhibitory activity.

In the title compound, C10H8O4, the almost planar coumarin ring system (r.m.s. deviation = 0.0216 Å from the plane through all 11 non-H atoms of the system) has hydroxymethyl and hydroxyl substituents at the 4- and 7-positions, respectively. In the crystal, two classical O—H...O hydrogen bonds generate a three-dimensional network structure.

C19H12ClF2N5O2, monoclinic, P21/n (no. 14), a = 14.405(9) Å, b = 7.579(5) Å, c = 17.610(9) Å, β = 95.856(13)°, V = 1913(2) Å3, Z = 4, Rgt(F) = 0.0464, wRref(F2) = 0.1134, T = 296 K. [ABSTRACT FROM AUTHOR]

The reaction of copper and nickel salts with the O,N-donor Schiff base 5-bromo-2-((2-hydroxyethylimino)methyl)phenol (HL) in methanol provides two new complexes [CuL2] (1) and [Ni2L2(N3)2(CH3OH)2]·CH3OH (2). The complexes have been characterized by analytical and spectroscopic measurements. The crystal structures of the complexes have been determined by X-ray crystallography. The Cu atom in the mononuclear complex 1 is in square planar coordination. The Ni atoms in the end-on azido bridged dinuclear complex 2 are octahedral coordination. The Schiff base ligands coordinate to the Cu and Ni atoms via NO and NOO donor sets, respectively. The antimicrobial activities of the complexes were assayed. [ABSTRACT FROM AUTHOR]

The reactions of Ni(OAc)2·2H2O with Schiff base ligands 5-bromo-2-((cyclopentylimino)methyl)phenol (HL¹) and 5-bromo-2-(((2-(isopropylamino)ethyl)imino)methyl)phenol (HL²) in methanol afforded two discrete trinuclear complexes [Ni3(L¹)2(μ2-η¹:η¹-OAc)2(DMF)2(BrSal)2] (1) and [Ni3(L²)2(μ2-η¹:η¹-OAc)2(μ2-η2:η¹-OAc)2] (2), where BrSal is the monoanionic form of 4-bromosalicylaldehyde. The complexes were characterized by elemental analysis, IR and UVVis spectroscopy. The crystal structures of the complexes have been determined by X-ray crystallography. In both complexes, the nickel atoms are in octahedral coordination geometries. The L¹ ligand coordinates to the nickel atoms through the phenolate O and imino N atoms, and the L² ligand coordinates to the nickel atoms through the phenolate O, imino N and amino N atoms. The antimicrobial activities of the complexes were assayed. [ABSTRACT FROM AUTHOR]

Bearing capacity of belled pier foundation is critical in designing transmission lines in coarse saline soil region. This paper describes model test results on belled pier foundations. Axial uplift behaviours including failure modes, load-displacement curves, and ultimate uplift bearing capacity were discussed. The failure planes in four cases were obtained from pulled out cone-shaped bodies. An empirical equation was developed with a critical parameter of an uplift angle in design. Results indicate the range where the ground uplift shows circular extension at higher loads and the overall shear failure finally occurred. The load-displacement curves are primarily softening, and the uplift bearing capacity for coarse-grained saline soils (CSS) in the crystalline state increases at larger thickness, higher than that in dissolved state. Failure planes all exhibit approximately linear change from bottom to up. The angles of uplift for soils in crystalline and dissolved states can be taken as 34° and 18°, while 32° for the conventional for the sake of safety. Uplift behaviour of belled piers in CSS was modelled incorporating a practical interface model, with both failure planes and plastic range. [ABSTRACT FROM AUTHOR]

Using the density functional theory calculations with the PBE exchange-correlation energy functional, we have studied the low-energy structures and electronic properties of Ni-Al alloy clusters for adsorbing or doping an aluminum atom to Ni (n = 13, 19, 23, 26, 29 and 55) clusters. The most stable structures of NiAl are viewed as adding an Al atom at the hollow triangle and rhombus site of the icosahedron (n = 13, 55) and double-icosahedron (n = 19, 23, 26 and 29) structures, respectively. For NiAl, it can be seen that an Al atom gradually moves from surface (n = 13, 19, 23 and 26) to the interior site (n = 29, 55) in the most stable structures. The electronic properties of the Ni-Al alloy clusters including binding energies, magnetic properties, charge transfer and density of states have also been studied. [ABSTRACT FROM AUTHOR]

Manipulating nanowire assembly could help the design of hierarchical structures with unique functionalities. Herein, we first report a facile solution-based process under ambient conditions for co-assembling two kinds of nanowires which have suitable composition and functionalities, such as Ag and Te nanowires, for the fabrication of flexible transparent electrodes. Then Te nanowires can be etched away easily, leaving Ag nanowire networks with controllable pitch. By manipulating the assembly of Ag and Te nanowires, we can precisely tailor and balance the optical transmittance and the conductivity of the resulting flexible transparent electrodes. The network of Ag nanowires which have tunable pitch forms a flexible transparent conducting electrode with an averaged transmission of up to 97.3% and sheet resistances as low as 2.7 W/sq under optimized conditions. The work provides a new way for tailoring the properties of nanowire-based devices. [ABSTRACT FROM AUTHOR]

The novel title organic salt, 4C5H7N2+·C24H8O84−·8H2O, was obtained from the reaction of perylene-3,4,9,10-tetracarboxylic acid (H4ptca) with 4-aminopyridine (4-ap). The asymmetric unit contains half a perylene-3,4,9,10-tetracarboxylate (ptca4−) anion with twofold symmetry, two 4-aminopyridinium (4-Hap+) cations and four water molecules. Strong N-H...O hydrogen bonds connect each ptca4− anion with four 4-Hap+ cations to form a one-dimensional linear chain along the [010] direction, decorated by additional 4-Hap+ cations attached by weak N-H...O hydrogen bonds to the ptca4− anions. Intermolecular O-H...O interactions of water molecules with ptca4− and 4-Hap+ ions complete the three-dimensional hydrogen-bonding network. From the viewpoint of topology, each ptca4− anion acts as a 16-connected node by hydrogen bonding to six 4-Hap+ cations and ten water molecules to yield a highly connected hydrogen-bonding framework. π-π interactions between 4-Hap+ cations, and between 4-Hap+ cations and ptca4− anions, further stabilize the three-dimensional hydrogen-bonding network. [ABSTRACT FROM AUTHOR]

Two new complexes with 5-methyl-1-(pyridine-3-yl)-1H-1,2,3-triazole-4-carboxylic acid (Hmptc) ligand: [Cd(mptc)2(H2O)4] (1) and [Cu(mptc)4 ⋅ 2H2O]n (2) were prepared and their crystal structures were determined by single crystal X-ray diffraction analyses. In complex 1, the Cd(II) ions coordinates with the pyridyl nitogen atom from the Hmptc ligand, forming a mononuclear Cd(II) compound. Complex 2 exhibits a novel two-dimensional (2D) polymer in which four Hmptc ligands stabilize the Cu(II) atom. And the coordination involves one nitrogen atom of the triazole, one oxygen atom of the carboxylic acid and the pyridyl nitrogen atom. In addition, FT-IR and solid-state fluorescent emission spectroscopy of two compounds have been determined. [ABSTRACT FROM AUTHOR]

The self-assembly of one equivalent each of copper bromide and ammonium thiocyanate with O,N-donor Schiff base ligands 2-bromo-6-[(2-dimethylaminoethylimino)methyl]phenol (L1) and 2-bromo-6-[(2-ethylaminoethylimino)methyl]phenol (L2) in methanol under aerobic conditions provide two mononuclear copper(II) complexes [CuL1(NCS))] (1) and [Cu(L2)2]·2Br (2). The complexes have been characterized by analytical and spectroscopic measurements. The crystal structures of the complexes have been determined by X-ray crystallography. In both complexes, the metal centers are in square planar coordination geometries. The L1ligand coordinates the metal ion through the three N,N,O donor atoms, while the L2ligand coordinates the metal ion merely through the imine-N and the phenolate-O atoms. Slight change in the terminal groups of the Schiff base ligands as well as the formation of hydrogen bonds can lead to totally different structures during the self-assembly processes. [ABSTRACT FROM PUBLISHER]

Abstract: Two new macrocyclic hexanuclear metal(III) 18-metallacrowns-6, [Mn6(acshz)6(H2O)6]·18H2O (1) and [Fe6(acshz)6(CH3OH)6]·6CH3OH·6H2O (2), have been synthesized and characterized, where acshz3− is N-acetyl-5-chlorosalicylhydrazidate. These crystal structures contain neutral 18-membered metallacrown rings consisting of six metal(III) ions and six acshz3− ligands. The ring is formed by the succession of six structural moieties of the type [M(III)–N–N] through hydrazide N–N groups bridging the ring metal ions. The ligand enforces the metal ions to form the stereochemistry of a propeller configuration with alternate Λ/Δ or Δ/Λ forms. The largest diameters of the hexanuclear rings are about 6.97Å at the entrance and 9.53Å at the centre of the cavity for 1; and 7.94 and 10.24Å for 2, respectively. The solution integrity and stability of the metallacrowns were confirmed using electrospray ionization ESI-MS and UV–Vis spectroscopy in methanol. Antibacterial screening data indicate the formation of the metallacrown 1 reduces the antimicrobial activity of the ligand H3acshz hugely, while metallacrown 2 has strong antimicrobial activity against Bacillus subtilis (B. subtilis). [Copyright &y& Elsevier]

Abstract: The reaction of N-propionyl-5-chlorosalicylhydrazide (H3pcshz) with Mn(OAc)2 ·4H2O in methanol solution gives a novel 18-metallacrown-6 [Mn(pcshz)(CH3OH)]6 ·4CH3OH·4H2O (1). The structure of 1 has been determined by X-ray diffraction and it crystallizes in the monoclinic system and space group P2(1)/n. The ring of the metallacrown is consisted of six interlink [Mn–N–N] repeated units through hydrazide N–N group bridging the ring manganese ions. And the ligand enforces the metal ions to form the stereochemistry as a propeller configuration with alternation Λ/Δ form. The largest diameters of the disc-shaped hexanuclear ring are about 8.82Å at entrance, 9.83Å at the central of the cavity, respectively. The solution integrity and stability of the metallacrown was studied by electrospray ionization (ESI)-MS and UV–Vis spectroscopy. The results show it is soluble and stable in methanol. Antibacterial screening data indicate the forming of the complex weakens dramatically the antibacterial activity of the ligand H3pcshz except for Eschericha coli. [Copyright &y& Elsevier]

C12H12N8O7Zn, monoclinic, P21/c (no. 14), a = 8.2116(3) Å, b = 11.1926(4) Å, c = 17.3488(7) Å, β = 96.2450(10)°, V = 1585.05(10) Å3, Z = 4, Rgt(F) = 0.0263, wRref(F2) = 0.0722, T = 150(2) K. [ABSTRACT FROM AUTHOR]

Two colorimetric thiourea-based chemsensors with two relatively rigid arms, 2A and 2B , were synthesized. Their binding abilities with halide anions, AcO - , were studied by UV-Vis spectroscopy in DMSO. The two sensors showed a notable selective color response to F - anion from colorless to green-yellow in recognition. The structures of the two sensors and their binding behaviors are discussed. The association constants were calculated by nonlinear fittings of 1:1, 1:2 or 1:1 to 1:2. [ABSTRACT FROM AUTHOR]

Abstract: A novel cross-net-shaped metallamacrocycle, (H4L=(Z)-3-(salicylhydrazinocarbonyl) propenoic acid), has been prepared and characterized. The crystal structure contains seven crystallographically unique manganese ions, in which two opening 13-membered metallacrown rings and two strands, Mn–N–N–Mn, are bridged by eight μ-maleoyl groups. The high nuclearity of the molecule shows large magnetic moments, with the value of μ eff at 300K is 19.01μB. [Copyright &y& Elsevier]

Two-dimensional (2D) materials are ultra-thin crystals with layered structures that have a monolayer and multiple layers of atomic thickness. Due to excellent performance, 2D materials represented by graphene have caused great interest from researchers in various fields, such as nano-electronics, sensors, solar cells, composite materials, and so on. In recent years, when graphite was used for liquid phase lubrication, there have been many disadvantages limiting its lubrication properties, such as stable dispersion, fluidity and so on. Therefore, 2D materials have been used as high-performance liquid-phase lubricant additives, which become a perfect entry point for high-performance nano-lubricants and lubrication applications. This review describes the application of 2D materials as additives in the field of liquid-phase lubrication (such as lubricating oil and water lubrication) in terms of experimental content, lubrication performance, and lubrication mechanism. Finally, the challenges and prospects of 2D materials in the lubrication field were also proposed. [ABSTRACT FROM AUTHOR]

The article discusses the crystal structure of N-(1-benzyl-2-oxoindolin-3-yl)-N-p-tolylbenzofuran- 2-carboxamide, whose chemical formula is C31H24N2O3. Topics discussed include its physical properties, chemical formula, chemical structure, and its atomic coordinates and displacement parameters.

The article discusses the crystal structure of N-(1-benzyl-2-oxoindolin-3-yl)-N-p-tolylbenzofuran- 2-carboxamide, whose chemical formula is C31H24N2O3. Topics discussed include its physical properties, chemical formula, chemical structure, and its atomic coordinates and displacement parameters.

Three novel complexes, [Cu( L ) 2 (H 2 O)]( 1 ), [Zn( L ) 2 (H 2 O) 2 ]·CH 3 OH·1.5H 2 O( 2 ), and [Ni( L ) 2 (H 2 O) 1.8 ]·CH 3 OH·1.2H 2 O ( 3 ) (HL = 2-{4-[bis(4-fluorophenyl)methyl]pipera-zin-1-yl} acetic acid), were synthesized and structurally determined by single-crystal X-ray diffraction. Molecular docking study preliminarily revealed that complex 1 had potential Monoamine oxidase B inhibitory activity. All acquired compounds were tested against rat brain MAO-B in vitro. In accordance with the result of calculation, it showed complex 1 (IC 50 = 1.85 ± 0.31 μ M) have good inhibitory activity against MAO-B at the same micromolar concentrations with positive control Iproniazid Phosphate (IP, IC 50 = 7.59 ± 1.17 μ M). These results indicated that complex 1 was a potent MAO-B inhibitor. [ABSTRACT FROM AUTHOR]

C19H12ClF2N5O2, monoclinic, P21/n (no. 14), a = 14.405(9) Å, b = 7.579(5) Å, c = 17.610(9) Å, β = 95.856(13)°, V = 1913(2) Å3, Z = 4, Rgt(F) = 0.0464, wRref(F2) = 0.1134, T = 296 K. [ABSTRACT FROM AUTHOR]

Abstract: The multidentate ligand, 4-(5′-chlorosalicylhydrazinocarbonyl) butyric acid, has been synthesized and reacted with FeCl3 to produce the iron(III) 18-metallacrown-6 complex [FeIII 6(C13H12N2O5Cl)6(CH3OH)6]·5CH3OH. In the complex the ligand 4-(5′-chlorosalicylhydrazinocarbonyl) butyric acid was esterified and transferred into methyl 4-(5′-chlorosalicylhydrazinocarbonyl) butyrate. In the crystal structure, the hexanuclear 18-membered rings of iron atoms are linked by six hydrazide N–N groups. The deprotonated and esterified ligand acts as a trianionic pentadentate ligand, one phenolate oxygen, one hydrazide nitrogen and one carbonyl oxygen in the ligand are bound to one Fe3+ cation, and the other carbonyl oxygen plus the other hydrazide nitrogen in the same ligand are chelated to an adjacent Fe3+ cation. In hydrochloric acid the metallacrown [FeIII 6(C13H12N2O5Cl)6(CH3OH)6]·5CH3OH can be treated with SnCl2 to obtain purified ester methyl 4-(5′-chlorosalicylhydrazinocarbonyl) butyrate. [Copyright &y& Elsevier]

In the title compound, [Rh(C6H5N4)Cl2(C12H27P)2], the RhIII ion is chelated by the singly deprotonated 2,2′-biimidazolate (Hbim−) ligand and coordinated by two chloride ions and two tri-n-butylphosphane ligands. The chloride ions and N atoms of the Hbim− ligand lie in a plane where the sum of X—Rh—X angles between cis sites is 360°. The phosphane ligands occupy the sites perpendicular to the plane, completing the overall distorted octahedral coordination sphere. The complex forms a self-complementary hydrogen-bonded dimer with the inversion-related complex through N—H...N hydrogen bonds.

As one of the important structural materials in nuclear industry, the corrosion resistance of zirconium alloy limits their in-pile application. Therefore, it is necessary to investigate the corrosion mechanism of zirconium alloys. The zirconium-oxygen reaction at the O/M interface is one of the factors that affect the oxidation process. There are few reports in this regard. Ideally, the reaction process at the O/M interface has certain relevance with the initiation oxidation of zirconium, which provided a new way to investigate the reaction process by observing the initiation oxidation behaviours. To investigate the oxidation behaviours of zirconium alloy at the initial stage, in this paper, zircaloy-4 TEM thin foil specimens in 3 mm diameter were studied by TEM observation after heating in air condition with a vacuum of 3 Pa at 280 °C, 290 °C and 300 °C for 30 min exposures. The results show that, ZrO 2 begin to nucleate at a size of 3–5 nm at a high Zr/O ratio of 10.4 and oxide layer formed while Zr/O was 4.6. As a result of stress caused by the P.B ratio of Zr, slip bands formed and a bcc structure sub-oxide b-ZrOx (a = 0.51 nm) grew up along with the slip bands was observed. At both sides of b-ZrOx, two hcp structure sub-oxides having the same a -axis lattice parameter and different c -axis lattice parameter were detected. [ABSTRACT FROM AUTHOR]

Abstract: The trianionic heptadentate ligand, (Z)-3-(5′-chlorosalicylhydrazinocarbonyl) propenoic acid, has been synthesized and reacted with FeCl3·6H2O, to produce the complex [FeIII 6(C12H8N2O5Cl)6(H2O)4(CH3OH)2]·8H2O·4CH3OH. In the self-assembly process the ligand was esterified and transferred into (Z)-methyl 3-(5′-chlorosalicylhydrazinocarbonyl) propenoate. In the crystal structure, the neutral Fe(III) complex contain a 18-membered metallacrown ring consisting of six Fe(III) and six trianionic ligands. The 18-membered metallacrown ring is formed by the succession of six structural moieties of the type [Fe(III)–N–N]. Due to the meridional coordination of the ligands to the Fe3+ ions, the ligands enforce the stereochemistry of the Fe3+ ions as a propeller configuration with alternating Λ/Δ forms. The metallacrown can be treated with SnCl2 or Zn powder to obtain purified ester. [Copyright &y& Elsevier]