Prediction and controlling for welding deformation of propeller base structure

Welding deformation often brings about manufacturing problems such as dimensional inaccuracies during assembly and reduces fabrication efficiency.Prediction and controlling welding deformation can help to improve the quality of welded structures.In this paper,the welding deformation of propeller base struc-tures is predicted by means of numerical approaches and mechanical constraints are proposed to control deformations in welding process.Thermal elasto-plastic finite element method(TEP FEM)is employed to simulate welding process of the base structure.Computed accuracy of welding deformation by TEP FEM analysis is verified by comparing with experimental data of tee joint welding.Results show that welding deformations of the base mainly comprise out-of-plane distortion of ring fringe and radial distortion of cylindrical plate.Exerting mechanical constraints of fixed points at fringe and rigid supports inside cylin-der can decrease out-of-plane and radial distortions effectively.The numerical approach adopted in this article can serve as an effective tool to optimize welding process planning in integrated design method.

Optimal design and effectiveness evaluation for inerter-based devices on mitigating seismic responses of base isolated structures

The optimal design and effectiveness of three control systems,tuned viscous mass damper(TVMD),tuned inerter damper(TID)and tuned mass damper(TMD),on mitigating the seismic responses of base isolated structures,were systematically studied.First,the seismic responses of the base isolated structure with each control system under white noise excitation were obtained.Then,the structural parameter optimizations of the TVMD,TID and TMD were conducted by using three different objectives.The results show that the three control systems were all effective in minimizing the root mean square value of seismic responses,including the base shear of the BIS,the absolute acceleration of structural SDOF,and the relative displacement between the base isolation floor and the foundation.Finally,considering the superstructure as a structural MDOF,a series of time history analyses were performed to investigate the effectiveness and activation sensitivity of the three control systems under far field and near fault seismic excitations.The results show that the effectiveness of TID and TMD with optimized parameters on mitigating the seismic responses of base isolated structures increased as the mass ratio increases,and the effectiveness of TID was always better than TMD with the same mass ratio.The TVMD with a lower mass ratio was more efficient in reducing the seismic response than the TID and TMD.Furthermore,the TVMD,when compared with TMD and TID,had better activation sensitivity and a smaller stroke.

Synthesis and Crystal Structure of a Zinc(II) Complex Salt with the Schiff Base of Picolinaldehyde N-oxide and Semicarbazone

The title zinc（Ⅱ） complex salt [Zn（H2O）6]（ClO4）2-（PNOS）4, where PNOS is derived from picolinaldehyde N-oxide with semicarbazone, has been prepared and structurally characterized by X-ray single-crystal analysis. It crystallizes in triclinic, space group PI with a = 7.529（3）, b = 10.206（4）, c = 14.678（6）A, a = 86.293（6）, β= 87.686（7）, γ= 81.382（6）°, C28H44Cl2N16O22Zn, Mr = 1093.06, V = 1112.3（8） ,A^3 Z = 1, Dc = 1.632 g/cm^3, S = 1.089, μ（MoKa） = 0.773 mm^-1, F（000） = 564, the final R = 0.0438 and wR = 0.1076 for 3888 independent reflections with Rint = 0.0224. The crystal structure possesses a [Zn（H2O）6]^2＋ cation, two ClO4^- anions and four PNOSs. In the crystal structure, Zn^2＋ cation is located at the symcenter and coordinated by six water molecules. In [Zn（H2O）6]^2＋, an elongate octahedral complex cation, the average Zn-O bond length is 2.087（2） A. There exist a lot of H bonds in the structure, linking the cation [Zn（H2O）6]^2＋, anion ClO4^- and PNOS to form a 3D network.

Structured Illumination Chip Based on Integrated Optics

A compact structured illumination chip based on integrated optics is proposed and fabricated on a silicon-on- insulator platform. Based on the simulation of Caussian beam interference, we adopt a chirped diffraction grating to achieve a specific interference pattern. The experimental results match well with the simulations. The portability and flexibility of the structured illumination chip can be increased greatly through horizontal encapsulation. High levels of integration, compared with the conventional structured illumination approach, make this chip very compact, with a footprint of only around 1 mm2. The chip has no optical lenses and can be easily combined with a microfluidic system. These properties would make the chip very suitable for portable 3D scanner and compact super-resolution microscopy applications.

Polarization-Insensitive Magnetic Quadrupole-Shaped and Electric Quadrupole-Shaped Fano Resonances Based on a Plasmonic Composite Structure

A combined structure with the unit cell consisting of four sub-units with 90° rotation in turn is designed. Each of sub-units is composed of two gold rods in transverse arrangement and one gold rod in longitudinal arrangement. Simulating electromagnetic responses of the structure, we verify that the structure exhibits the double Fano resonances, which originate from the coupling between magnetic quadrupoles and electric dipoles and the coupling between electric quadrupoles and electric dipoles. Simulation results also demonstrate that the structure is polarization-insensitive and shows an analogue of electromagnetically induced transparency at the two Fano resonances. Such a plasmonic structure has potential applications in photoelectric elements.

Syntheses and Crystal Structures of Calix[4]arene Dithiocarbazate Schiff Bases

The regioselective syntheses of novel p-tert-butylcalix[4]arenes with functional aldehyde and dithiocarbazate Schiff base groups were carried out. p-tert-Butylcalix[4]arene was alkylated with o-, p-（ω-chloroalkoxy）- benzaldehydes in the system of K2CO3/KI/CH3CN to give calixarene 1,3-dialdehydes. Then the condensation reactions of active calixarene aldehydes with S-methyl and S-benzyldithiocarbazate, calixarene sulfur-containing Schiff bases were efficiently obtained in satisfied yields. The single crystal analysis of the four representative products shows that calixarene aldehydes and Schiff bases exist in cone conformation and there are interesting intermolecular hydrogen-bands and π...π interaction in the crystals.

High-Efficiency Green Phosphorescent Organic Light-Emitting Diode Based on Simplified Device Structures

A high-efficiency green phosphorescent organic light emitting diode with a simplified structure is achieved that is free of a hole transport layer. The design of this kind of device structure not only saves the consumption of organic materials but also greatly reduces the structural heterogeneities and effectively facilitates the charge injection into the emissive layer. The resulting green phosphorescent organic light-emitting diodes （PHOLEDs） exhibit higher electroluminescent efficiency. The maximum external quantum efficiency and current efficiency reach 23.7% and 88 cd/A, respectively. Moreover the device demonstrates satisfactory stability, keeping 23.7% and 88cd/A, 22% and 82cd/A, respectively, at a luminance of 100 and 1000cd/m2. The working mechanism for achieving high efficiency based on such a simple device structure is discussed correspondingly. The improved charge carrier injection and transport balance are proved to prominently contribute to achieve the high efficiency and great stability at high luminance in the green PHOLEDs.

PHYLETIC RELATIONSHIP OF PROTEIN STRUCTURES BASED ON SPATIAL PREFERENCE OF RESIDUES

A distance measure that infers to indicate the evolutionary relationship of protein structures has been developed based on spatial preference factors of residues. The spatial preference factor is a reflection of the environment of residues in tertiary structure. Compared with the phyletic relationships derived from sequence homologies and three-dimensional structures, we find that the two lines of evolution are similar in general. This approach is applied to a group of glins here.

Synthesis and Crystal Structure of a New 2D O-bridged Copper(Ⅱ) Coordination Polymer Constructed from Sulfonate-derived Schiff Base

A new chain-like coordination polymer, namely, [CuL]n （1, Na2L = 2-[（2-hydroxy- benzylidene）-amino]-benzenesulfonic acid sodium salt）, has been synthesized and characterized by single-crystal X-ray diffraction, IR spectroscopy and elemental analysis. Complex 1 crystallizes in monoclinic system, space group P21/c with a = 9.2296（16）, b = 10.4754（18）, c = 12.200（2） A, β = 102.392（2）°, V = 1152.0（3）A3, CI3H9CuNOaN, Mr = 338.83, Dc = 1.953 g/cm3, Z = 4, F（000） = 684, p = 2.089 mm-1, the final R = 0.0376 and wR = 0.0956. X-ray diffraction analyses indicate that 1 displays a square-pyramidal metal center with NO4 donor sets. The sulfonate-derived Schiff base serves as a common N,O,O＇-tridentate and a unique O-bridged ligand connecting the metals. Dinuclear copper complexes serve as secondary building blocks （SBUs） to construct an unusual 2D coordination network. In the crystal, the components form a stable 3D supramolecular architecture by C-H...O interactions and to-stacking

Memory Behaviors Based on ITO/Graphene Oxide/Al Structure

We investigate the memory properties of the ITO/graphene oxide/Al diodes. It is found that the devices show different memory behaviors with the diverse geometry and thickness of Al. When the thickness of the Al electrode is relatively thick, the device of the cross-point Al electrode shows a three-level memory effect, and the counterpart device of the cross-bar Al electrode exhibits a volatile static random access memory effect. When the thickness of the AI electrode is thinner, the above devices demonstrate a flash memory effect. The different memory behaviors of ITO/GO/AI diodes are ascribed to the mode and degree of reduction and oxidation of GO.

Syntheses, Crystal Structures and Antibacterial Activities of Cobalt(Ⅱ) and Manganese(Ⅱ) Complexes with Schiff Base Ligand Derived from Tryptamine

Two new mononuclear complexes, namely [Co（L）2]（1） and [Mn（L）2]（2）（HL = N-（3-methylsalicylidene）tryptamine）, have been synthesized by the reactions of the ligand with cobalt acetate or manganese acetate in anhydrous ethanol. The crystal structures of the complexes were characterized by IR spectrum, elemental analysis, PXRD and single-crystal X-ray diffraction analysis. Complex 1 crystallizes in monoclinic, space group C2/c, with a = 23.146（2）, b = 9.4864（10）, c = 13.9261（15）A, β = 102.898（2）°, V = 2980.6（5） ？3, Z = 4, Dc = 1.367 g/cm3, F（000） = 1284 and μ = 0.616 mm^-1. Complex 2 crystallizes in monoclinic, space group P21/n, with a = 14.807（11）, b = 13.118（10）, c = 16.663（13） A, β = 111.237（14）°, V = 3017（4） A^3, Z = 4, Dc = 1.342 g/cm^3, F（000） = 1276 and μ = 0.477 mm-1. The units of complex 1 are linked by intermolecular N–H…π hydrogen bonds into infinite 1D chains, which are further extended into a 3D supramolecular structure by a series of π···π stacking interactions. The units of complex 2 are linked by intermolecular N–H…π hydrogen bonds and C–H…π hydrogen bonds into an infinite 3D supramolecular structure. Meanwhile, the antibacterial activities of the ligand and its complexes have been tested against four kinds of bacteria. The results show that the three compounds all have excellent antibacterial activities and that 1 and 2 possess stronger inhibiting effects against the bacteria than the Schiff base.

Crystal Structure of a Hexanuclear Silver（Ⅰ） Compound [Ag_6L^66]·4DMF and Luminescence Discussion of a Series of Silver（Ⅰ） Clusters

A new silver（Ⅰ） compound 6 （[Ag6L66]·4DMF） containing thiosemicarbazone with the group of 2-chloro-1-benzene was synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analysis and fluorescence spectrum. The title compound 6 crystallizes in monoclinic, space group C2/c with a = 26.9236（18）, b = 15.2553（8）, c = 24.6237（13） , β = 103.0680（10）°, V = 9851.7（10）3, C58H66Ag6Cl6N20O3S6, Mr = 2143.59, Dc = 1.445 g/cm3, μ（MoKα） = 1.503 mm-1, F（000） = 4232, Z = 4, the final R = 0.0565 and wR = 0.1654 for 5831 observed reflections （Ⅰ 〉 2σ（Ⅰ））. Similar to the structure of the compounds we have reported, compound 6 also exhibits a hexanuclear silver（Ⅰ） cluster. In the cluster, the S atom of ligand L6 （L6 = 2-chloro-1-benzaldehyde thiosemicarbazone） served as a triply bridged chelator to connect the six silver atoms into a Ag6L66 cluster. The luminescence property of compound 6 was investigated at room temperature and compared with other similar compounds in order to find the factors influencing their luminescent property.

Syntheses and Crystal Structures of Hg(Ⅱ)and Ag(Ⅰ)Complexes Containing 2-Acetylpyridine-paminobenzoylhydrazone Ligand

The two complexes [HgI_2L]（DMF）（1） and [AgL_2]（ClO_4）（CH_3CN）（2） were synthesized from the reaction of Schiff base ligand（2-acetylpyridine-p-aminobenzoylhydrazone）（L） with HgI_2 or AgClO_4 respectively. The compounds are characterized by ^1H NMR,FTIR and elemental analysis. The structures of the ligand and two complexes are measured via single-crystal X-ray diffraction. In these two complexes,the structures are both distorted triangular bipyramids with five-coordinated centers.

Prediction of Superconductivity for Oxides Based on Structural Parameters and Artificial Neural Network Method

Superconductive properties for oxides were predicted by artificial neural network (ANN) method with structural and chemical parameters as inputs. The predicted properties include superconductivity for oxides, distributed ranges of the superconductive transition temperature (Tc) for complex oxides, and Tc values for cuprate superconductors. The calculated results indicated that the adjusted ANN can be used to predict superconductive properties for unknown oxides.

Synthesis and Crystal Structure of a Novel Bis(chlorido)-bridged One-dimensional Chain-like Copper(Ⅱ) Polymer

A copper（Ⅱ） complex [LCu2Cl4]n was synthesized by a new bis-Schiff base ligand containing quinoline unit, 1,4-bis[2-（4-fluorophenyl）iminomethyl-8-quinolinoxy]butane（L）. X-ray crystal structure shows that it is a binuclear complex, and the crystal belongs to the triclinic system, space group P1, with a = 9.387（2）, b = 9.968（2）, c = 10.291（2） ？, α = 87.532（3）, β = 63.762（2）, γ = 86.628（3）o, V = 862.1（3） ？^3, Z = 1, Dc = 1.640 Mg/m^3, F（000） = 428, R = 0.0416 and wR = 0.1141. Each Cu（Ⅱ） metal ion coordinates with a quinoline N atom, an imine N atom, an ether oxygen atom and three chlorides, forming a distorted six-coordinated octahedronal structure. Each copper（Ⅱ） complexation unit links with one of the adjacent ligand copper complexation units through the chlorido bridging groups, thus generating an infinite one-dimensional chain structure. Such 1D chains further construct a 2D network structure by π-π stacking interactions.

Synthesis, Structure and Comparison of Luminescent Property between Two Hexanuclear Silver(Ⅰ) Thiosemicarbazone Clusters

A new silver（Ⅰ） compound 4 containing thiosemicarbazone with group 2-quinoline was synthesized and structurally characterized by single-crystal X-ray diffraction, elemental analysis and fluorescence spectrum. Compound 4 crystallizes in triclinic, space group P1 with a = 12.2710（9）, b = 16.9281（13）, c = 17.2984（13）, α = 112.8500（10）, β = 103.4890（10）, γ = 102.6860（10）°, V = 3020.9（4） 3, C80H94Ag6N28O6S6, Mr = 2383.41, Dc = 1.310 g/cm3, μ（MoKα） = 1.108 mm-1, F（000） = 1196, Z = 1, the final R = 0.0567 and wR = 0.1368 for 5112 observed reflections （I 〉 2σ（I））. Similar to the structure of compound 2 we have reported, compound 4 also exhibits a hexanuclear silver（Ⅰ） cluster. In the cluster, the S atom of ligand L4 （L4 = 2-quinolinecarboxaldehyde thiosemicarbazone） serves as a triply bridged chelator to connect the six silver atoms into a Ag6L46 cluster. The luminescence property of 4 is investigated at room temperature and compared with that of 2.

Synthesis and Crystal Structure of 5-Nitro-4-salicylidene-amino-3-methyl-1,2,4-triazol-5-thione

The crystal structure of 5-nitro-4-salicylideneamino-3-methyl-1,2,4-triazole-5-thione ([C 10 H 9N 5O 3S]·HCON(CH 3) 2, M r=352.38)(CCDC No. 216094) was determined by the single crystal X-ray diffraction method. The crystal belongs to a triclinic system, the space group is P1 with unit cell constants a= 0.6113(2) nm, b=1.0836(4) nm, c=1.3132(5) nm, α=74.523(7)°, β=117.68(3)°, γ= 79.769(7)°, V=0.8245(5) nm 3, Z=2, D c=1.419 g/cm 3, μ=0.228 mm -1 , F(000)=368, R and wR are 0.0579 and 0.1040, respectively, beasd on 3348 unique reflections of which 1925 reflections were observed[I>2σ(I)]. The results indicate that the title compound can be assigned to the thione tautomeric form rather than the thiol tautomeric form. It contains a five membered triazole ring and a phenyl ring with a dihedral angle of 4.35°. The intermolecular hydrogen bond N3_H3…S1, O1_H1…O4 can be observed.

Synthesis,Crystal Structure and Biological Activity of(E)-3-Chloro-2-(2-(2-methylbenzylidene)-hydrazinyl)pyridine

The novel Schiff base（E）-3-chloro-2-（2-（2-methylbenzylidene）hydrazinyl）pyridine was synthesized and characterized by ^1H NMR, MS, elemental analysis and X-ray diffraction. The compound crystallizes in monoclinic space group Pbca with a = 14.6638（3）, b = 7.7522（2）, c = 20.3850（4） A, V = 2317.30（9） A^3, Z = 8, R = 0.063 and w R = 0.1922. The title compound exhibits good antifungal activity against Stemphylium lycopersici（Enjoji） Yamamoto and Fusarium oxysporum sp. cucumebrium.

Crust-mantle structure under South Pole and Ross Sea Beach in Antarctica

A comparison of theoretical seismograms under discussion with four teleseismograms recorded by WWSSN of SBA(New Zealand) and SPA (U.S.A.),shows that the crustal thickness beneath South Pole is a double-layered structure, about 45 km ; crustal thickness below the Ross Sea Beach,a single structure, is about 24 km ;and at the depth of 350～450 km there exists a low velocity layer. The above results indicate the different tectonic characteristics on both sides of Antarctic Transantarctic Mountains.

Erratum to "Uniform Coverage of Fibres over Open-contoured Freeform Structure Based on Arc-length Parameter" [Chinese Journal of Aeronautics 21(2008)571-577]

It is regretted that the author corrections requested at the proof stage were not made accurately. There are some incorrect typings in two equations which will lead to inaccurate results if readers perform calculations directly