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The eastern Central Asian Orogenic Belt (CAOB) in NE China is a key area for investigating continental growth. However, the complexity of its Paleozoic geological history has meant that the tectonic development of this belt is not fully understood. NE China is composed of the Erguna and Jiamusi blocks in the northern and eastern parts and the Xing’an and Songliao-Xilinhot accretionary terranes in the central and southern parts. The Erguna and Jiamusi blocks have Precambrian basements with Siberia and Gondwana affinities, respectively. In contrast, the Xing ’an and Songliao-Xilinhot accretionary terranes were formed via subduction and collision processes. These blocks and terranes were separated by the Xinlin-Xiguitu, Heilongjiang, Nenjiang, and Solonker oceans from north to south, and these oceans closed during the Cambrian (ca. 500 Ma), Late Silurian (ca. 420 Ma), early Late Carboniferous (ca. 320 Ma), and Late Permian to Middle Triassic (260 –240 Ma), respectively, forming the Xinlin-Xiguitu, Mudanjiang-Yilan, Hegenshan-Heihe, Solonker-Linxi, and Changchun-Yanji suture zones. Two oceanic tectonic cycles took place in the eastern Paleo-Asian Ocean (PAO), namely, the Early Paleozoic cycle involving the Xinlin-Xiguitu and Heilongjiang oceans and the late Paleozoic cycle involving the Nenjiang-Solonker oceans. The Paleozoic tectonic pattern of the eastern CAOB generally shows structural features that trend east-west. The timing of accretion and collision events of the eastern CAOB during the Paleozoic youngs progressively from north to south. The branch ocean basins of the eastern PAO closed from west to east in a scissor-like manner. A bi-directional subduction regime dominated during the narrowing and closure process of the eastern PAO, which led to “soft collision” of tectonic units on each side, forming huge accretionary orogenic belts in central Asia.

Identifying the reserve quota of maintenance spares is an important foundation work in spare parts management. The higher the reserve quota of maintenance spares, the higher the service level, accordingly, stock funds occupied more. It is also a kind of large waste for the enterprise. Therefore, it is becoming more importance for making the best reserve quota. In this work, it was based on the consuming law of maintenance spares that the mathematical model was established, so service level of maintenance conditions was identified according to that. The best reserve quota was identified depend on the relationship between service level of maintenance condition and the best service level.

Abstract: It is known that natural systems are undeniably subject to random fluctuations, arising from either environmental variability or internal effects. In this paper, a spatial version of an epidemic model which contains some important factors, such as noise on the infective and diffusion processes on both the susceptible and infective, is investigated. From the numerical results, we know that noise can induce instability and enhance the oscillation of the species density and the cooperation between noise and diffusion gives rise to the appearance of a rich transport phenomenology. Our results show that noise can play a prominent role in the spatial epidemic model.

Two novel phosphonate compounds, Cui2Cuii[(3-C5H4N)CH(OH)PO3]2(1) and Zn[(3-C5H4N)CH(OH)PO3] (2), have been synthesized by solvothermal reactions of the corresponding metal salts with [hydroxy(3-pyridyl)methyl]phosphonic acid. Compound 1contains inorganic chains made up of CuiiO4planes and CPO3tetrahedra through corner sharing. These chains are connected by CuiON units through pyridine rings, forming a 3D open framework structure. Compound 2adopts a new type of pillared layered structure. The inorganic layer contains 8- and 16-membered rings made up of ZnO3N and CPO3tetrahedra. Pyridine rings are fixed between the inorganic layers through covalent bonds. The magnetic study shows that weak ferromagnetic interactions are mediated between magnetic centers in compound 1.

This paper describes the syntheses and characterization of two new copper(Ii) diphosphonates: [NH₃(CH₂)₂NH₃]₂[Cu₂(hedp)₂]·H₂O (1) and [NH₃CH(CH₃)CH₂NH₃]₂[Cu₂(hedp)₂] (2) (hedp = 1-hydroxyethylidenediphosphonate). Both compounds exhibit similar one-dimensional linear chain structures. The symmetrical {Cu₂(hedp)₂} dimers are connected by edge-shared {CuO₅} square pyramids and form infinite chains. The Cu(ii) ions are alternately bridged by O–P–O groups and O atoms. The Cu–O–Cu angles are 95.8(1) and 96.1(1)° for 1 and 2, respectively. Their magnetic properties show moderately strong antiferromagnetic interactions in both compounds.

The new macrocyclic compound bearing hydroxyethyl pendant arms containing p-xylyl spacers, 3,6,9,16,19,22-hexaaza-6,19-bis(2-hydroxyethyl)-tricyclo[22,2,2,211,14] triaconta-1,11,13,24,27,29-hexaene, crystallizes in the monoclinic space group P21/cwith a= 8.700(2) Å, b= 18.301(4) Å, c= 11.766(2) Å, β = 108.57(2)°. The two hydroxyethyl pendants are at the opposite sides of the macrocyclic plane. Benzene rings in macrocycle are parallel and exist the π-π weak interaction with distance of 4.28 Å. The crystal packing of the macrocycle is stabilized by the hydrogen bonds.

The synthesis and crystal and molecular structure of [Gd(H3L)(NO3)(H2O)](ClO4)2are reported. The complex crystallizes in the orthorhombic system, space group Pbca with lattice parameters a = 16.974(8), b = 20.010(4), c = 25.202(4) Å, and Dcalc= 1.736 mg m−3, forZ = 8. The coordination number of gadolinium (III) is nine, and its coordination geometry is a distorted monocapped square antiprisms. In the complex, three benzene rings make dihedral angles of 91.7, 92.7, 66.3°, respectively. A water molecule acts as a guest molecule encapsulated in the cryptate.

The complex [Sm(H3L)(NO3)(H2O)](NO3)2 · H2O was synthesized by the (2+3) condensation of tris(2-aminoethyl)amine with 2,6-diformyl-4-chlorophenol in the presence of Sm3+. Its crystal structure has been determined. In the complex the coordination number of Sm3+ is nine. A water molecule is encapsulated in the cryptate as a guest, confirmed by electrospray mass spectrometry, thermal analysis and the X-ray crystal structure.

An azide-bridged polymeric cationic chain complex, [LCu2(N3)2]n(ClO4)2n·n(H2O)**, where L=the dinucleating macrocyclic ligand bis-p-xylylBISDIEN, has been prepared and characterized by x-ray crystallography, u.v.-vis and i.r. spectra, and by magnetic measurements. The structure consists of cationic azide-bridged [LCu2(N3)2]2+(unit) chains, non-coordinated perchlorate anions and crystallized water molecules. The azide anion is bound to two copper atoms in neighboring units with an end-to-end bridging mode. In each unit, the copper atoms have a different coordination geometry; Cu(1) is a four-coordinated, distorted square-planar geometry, whereas Cu(2) is a five-coordinated, distorted square-pyramid. The electronic spectra of the title complex differ in anhydrous and in aqueous MeCN solutions, indicating that dissociation and solvation occur in aqueous solutions. The characteristic i.r. absorptions of azides and perchlorates are described. Magnetic moments vary from 2.05 (B.M.) at 300K to␣2.01 (B.M.) at 80K, which suggests that very weak interactions exist between the metals.

Syntheses and crystal structures of tris[2-(1-naphthalenyloxy)ethyl]amine 1and tris[2-(1-naphthalenyloxyl)ethyl]amine perchlorate 2are reported. Compound 1crystallizes in the rhombohedral system, space group R3¯ with a= 13.077(4), c= 29.011(8) Å, and Dcalc= 1.233g/cm3for Z= 6; compound 2crystallizes in the cubic system, space group P213 with lattice parameters a= 14.630(5) Å and Dcalc= 1.332g/cm3for Z= 4. In 1,three naphthalene rings make dihedral angles of 109.21, 70.78, 70.78,° respectively. In 2they make dihedral angles of 107.3, 72.7, 72.7° respectively. Deviation of N from the plane (C(12),C(12)i,C(12)ii) in 1is 0.3742 Å which is less than that in (2) (−0.4223 Å). The crystals structure is stabilized by van der Waals interactions in both compounds.

A new facile method—aminolysis of calix[4]arene esters to obtain lower rim double-1,2-amide-bridged calix[4]arenes is described. We also report the single crystal structure of compound 3which forms a long chain supramolecule in the solid state viaintermolecular hydrogen bonding.

Reaction of Me3In with 5, 6-benzoquinoline (1:1 molar ratio) resulted in the formation of the Lewis acid-base adduct Me3In(BQ)2. This adduct is much less air and moisture sensitive than the trialkyl indium. It was found to be a discrete 1:2 molecular adduct of trimethylindium. The stereochemistry about 5-coordinated indium is trigonal bipyramidal. 1H NMR spectra of the adduct revealed a downfield shift of the metal alkyl protons. The complex crystallizes in the orthorhombic space group Pbcn with a = 16.672(4), b = 7.537(4), c = 18.969(3)Å and Z = 4. The structure was refined to R = 0.040 for 1732 observed reflections. The In-N bond length is 2.709(2)Å. C-In-N bond angles are in the range of 85.56(6)-92.6(1)°. This compound has a structure different to corresponding BQ adducts with Me3Al and Me3Ga.

Four new NiII–NiII–NiII homotrinuclear complexes namely [Ni(α-BD)2{NiL2}](ClO4)2 [L = 1,10-phenanthroline (phen), 5-nitro-1,10-phenanthroline (5-NO2-phen), 2,2′-bipyridyl (bpy) or 4,4′-dimethyl-2,2′bipyridyl (Me2bpy) and (α-BD)− = α-benzyldioximato ion] have been prepared and characterized. Based on elemental analyses, i.r. spectra, conductivity measurements, extended α-benzyldioximato-bridged systems consisting of three nickel(II) ions in which the central nickel(II) ion has a square-planar environment and the end capped two nickel(II) ions have a distorted octahedral environment are proposed for these structures. The temperature dependence of the magnetic susceptibility for complexes (1) (phen), (2) (5-NO2-phen), (3) (bpy) and (4) (Me2bpy) were measured over the 77–300 K range and the observed data were successfully simulated by an equation based on the spin Hamiltonian operator (H^ = −2JS^1S^2), giving the exchange integral J = −13.31 cm−1 for (1), J = −7.37 cm−1 for (2), J = −8.96 cm−1 for (3) and J = −7.33 cm−1 for (4) These results indicate a weak antiferromagnetic spin exchange interaction between the two terminal nickel(II) io

The complex [Nd(HL)(NO3)(H3O)]NO3·6H2O was synthesized by the 2 4;+ 4;3 condensation of tris(2-aminoethyl)amine (tren) with 2,6-diformyl-4-chlorophenol in the presence of Nd3+ as the template. The complex has been characterized by elemental analysis, molar conductivity and IR spectroscopy. The crystal structure of the complex [Nd(HL)(NO3)(H3O)]NO3·2MeOH has been determined. The co-ordination number of neodymium(III) is nine and its co-ordination geometry is monocapped square antiprismatic. One oxonium ion acts as a guest molecule encapsulated in the cryptate. The existence of the oxomium ion was confirmed by electrospray mass spectrometry, thermal analysis, X-ray crystal structure determination and 1H NMR spectroscopy.

The title compound, [Zn(C7H8NO3S)2(H2O)4], has an octahedral coordination around the central Zn atom composed of two axial N atoms from the pyridine ligands and four equatorial O atoms of water mol­ecules, forming a monomeric centrosymmetric complex. The two Zn—N bond distances are 2.102 (3) Å, while the four Zn—O bond distances range from 2.114 (2) to 2.167 (2) Å. Packing is determined by hydrogen bonds formed by the water mol­ecules. The sulfonate group does not take part in coordination to the Zn atom.

In the title compound, 4‐(4H‐1,2,4‐triazol‐4‐yl­imino­methyl)­phenol hemi­hydrate, C9H8N4O·0.5H2O or (I)·0.5H2O, mol­ecules of (I) are arranged as layers running along the baxis through intermolecular O—H⋯N and C—H⋯O hydrogen bonds. These layers are stabilized by hydrogen‐bonded water mol­ecules to form three‐dimensional networks.

The new mixed valence layered cluster compound, [VvVivO4(OH)·0.5H2O]n, contains the first two-dimensional V-O cation [VvVivO4]nn+with water molecules and OH−anions interlayer region, and it’s structure was determinated by crystal X-ray diffraction, EPR and TG analysis.

The title 1,2,3‐triazole derivative (IIIe) exhibits the most powerful in vitro activity against A431 and K562 human tumor cell lines (IC50< 1.9 μg/ml).

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