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Hydrothermal reactions of isonicotinic acid (Hina), 2-sulfobenzoic acid (H(2)sba), d-block metal salts and lanthanide oxides/hydroxides yielded 17 three-dimensional (3D) 3d-4f and 4d-4f heterometallic coordination polymers (HCPs). They are formulated as [LaAg(sba)(ina)(2)](n) (1), [Ln(2)Ag(2)(sba)(2)(ina)(4)(H(2)O)(2)](n) [Ln = Pr (2), Nd (3), Sm (4), Eu (5), Gd (6), Tb (7), Dy (8), Ho (9), Er (10)] and [Ln(2)Cu(2)(sba)(2)(ina)(4)(H(2)O)(2)](n) [Ln = La (11), Pr (12), Nd (13), Sm (14), Eu (15), Gd (16), Tb (17)]. Their structures were characterized by single crystal X-ray diffraction, powder X-ray diffraction (XRD), infrared (IR) spectroscopy, elemental analysis (EA), and thermogravimetric analysis (TGA). It reveals that they represent two structural types of 3D HCPs. Furthermore, the investigations of their solid-state photoluminescent (PL) property demonstrate the extraordinary emission behaviors. HCP 1(La-Ag) exhibits tunable blue-to-green PL emissions by variation of excitation light. HCPs 6(Gd-Ag), 11(La-Cu), 12(Pr-Cu) and 16(Gd-Cu) show d(10)-metal-based ligand-to-metal charge transfer (LMCT) or metal-to-ligand charge transfer (MLCT) emissions. HCPs 3(Nd-Ag), 4(Sm-Ag), 5(Eu-Ag), 7(Tb-Ag), 8(Dy-Ag), 13(Nd-Cu), 14(Sm-Cu), 15(Eu-Cu) and 17(Tb-Cu) display characteristic PL emissions of the corresponding Ln(III) ions, while both d(10)-metal-based and 4f-metal-centered emissions are observed in the emission spectra of 4(Sm-Ag), 8(Dy-Ag), 14(Sm-Cu) and 17(Tb-Cu).

Recrystallization of enantiopure amino acid derivatives N-(2-pyridylmethyl)-alanine in MeOH resulted in high quality crystals of compounds 1 (L-Hpala) and 2 (D-Hpala). Self-assembly of L- or D-Hpala with Zn(CH3CO2)(2)center dot 2H(2)O in MeOH in a ratio of 2:1 produced two enantiopure neutral mononuclear complexes [Zn(L-pala)(2)]center dot H2O (3) and [Zn(D-pala)(2)] center dot H2O (4) with almost quantitative yields. X-ray single crystal diffraction analyses reveal that they are two-dimensional undulate homochiral supramolecular structures. Circular dichroism (CD) spectra confirm that 1 and 2, 3 and 4 are one pair of enantiomers, respectively. [Cu-1.5(spp)(bpy)(1.5)(H2O)(2)(NO3)](NO3)center dot 4H(2)O (5) was prepared by the self-assembly of Cu(NO3)(2)center dot 3H(2)O pala(-), and 4,4'-dipyridyl (bpy) in a H2O-EtOH mixture involving the in situ formation of a Schiff base ligand N-(2-pyridylmethyl)-pyruvic acid (spp(-)). Compound 5 crystallized in the cent rosymmetric C2/c space group. It features a three-dimensional supramolecular network by interconnection of an antenna-shaped Cu-containing sheet and a hydrogen bonded supramolecular layer in the alternate ...ABAB... stacking mode. The solid-state photoluminescence properties of 1 and 3 were also investigated.973 Program [2006CB932903, 200703815303]; NSFC [20873151, 20731005]; NSF of Fujian Province [2006F3134]; CA

Hydrothermal reactions of N-piperidinomethane-1-phosphonic acid (H 2 pmp) and oxalate anion with trivalent rare earth metal ions yielded 13 rare earth oxalatophosphonates with three closely related structural types, ranging from two-dimensional (2D) networks to three-dimensional (3D) frameworks. They are formulated as [Ln 3 (Hpmp) 5), Sm (6), Eu (7), Tb (8), Dy (9), Ho (10), Er (11), Yb (12), Y (13), type II structure], andTheir structures were characterized by single crystal X-ray diffraction, powder X-ray diffraction (PXRD), infrared (IR) spectroscopy, elemental analysis (EA), and thermogravimetric analysis (TGA), except that the structures of compounds 2 and 3 were confirmed by PXRD, IR, and EA. The effects of reaction conditions including pH value, reaction temperature, counterion, and stoichiometry of the starting materials on the structures have been discussed. Furthermore, the solid-state photoluminescence properties of the Eu (2 and 7) and Tb (3 and 8) compounds have been measured at room temperature. The two types of Eu and Tb compounds display intense red and green luminescence emissions, respectively, with lifetimes at the millisecond order.

ABSTRACT:The rheological behaviors of semi-aromatic transparent polyamide (SATPA) melt are investigated using a capillary rheometer. The effects of shear rate, shear stress, and temperature on the apparent viscosity a of SATPA are discussed. A correlation of non-Newtonian index with temperature is obtained. The results show the shear thinning of SATPA; meanwhile a decreases with increasing temperature and shear rate, and the viscous flow activation energy is further obtained from temperature dependence of the samples. It was concluded that the apparent viscosity a is sensitive to temperature at lower shear rate owing to the higher viscous flow activation energy; on the contrary, the influence of temperature effect on the apparent viscosity becomes minor at higher shear rate due to the lower viscous flow activation energy.

This is a new report on the early Eocene radiolarian fauna from the Sangdanlin section in the Gyirong region, along the southern margin of the Yarlung Zangbo Suture Zone. The Sangdanlin section measured in this study is divided into three lithostratigraphic units from bottom to top: the Zongzhuo, Sangdanlin, and Zheya formations. Abundant radiolarian fossils were obtained from the Sangdanlin section and 54 species of 30 genera were identified and assigned as follows: Cryptamphorella conara‐C. macropora the late Cretaceous Zone and Amphisphaera coronate, Buryella tetradica‐Bekoma campechensis, and B. bidartensis‐B. divaricata the Paleocene‐early Eocene Interval Zones. The Paleocene‐early Eocene radiolarian zones are comparable to the radiolarian zones RP4‐RP8 in New Zealand. Based on the data of radiolaria and lithofacies, it is suggested that the Zongzhuo Formation should be deposited along the base of the north‐facing, continental slope of the Greater Indian continental margin, and the Sangdanlin Formation should be a deep marine, sedimentary sequence located in a foreland basin. The early Eocene radiolarian fauna in the Sangdanlin Formation constrains the initial age of the India‐Asia collision to no later than 53.6 Ma.

Alzheimer's disease (AD) is one of the most common progressive neurodegenerative diseases, and the number of AD patients has increased year after year with the global aging trend. The onset of AD has a long preclinical stage. If doctors can make an initial diagnosis in the mild cognitive impairment (MCI) stage, it is possible to identify and screen those at a high-risk of developing full-blown AD, and thus the number of new AD patients can be reduced. However, there are problems with the medical datasets including AD data, such as insufficient number of samples and different data distributions. Transfer learning, which can effectively solve the problem of distribution discrepancy between training and test data and an insufficient number of target samples, has attracted increasing attention over recent years. In this paper, we propose a multi-source ensemble transfer learning (METL) approach by introducing ensemble learning and our tritransfer model that uses Tri-Training, which ensures the transferability of source data by the tri-transfer model and high performance through ensemble learning. The experimental results on the benchmark and AD datasets demonstrate that our proposed approach has effective transferability, robustness, and feasibility, and is superior to existing algorithms. Based on METL, we propose an auxiliary diagnosis system for the initial diagnosis of AD, which helps doctors identify patients in the MCI stage as quickly as possible and with high accuracy so that measures can be taken to prevent or delay the occurrence of AD.

An organic ligand 4-(1,2,4-triazol-1-yl) benzoic acid (Htzbc) with a nonlinear optical (NLO) chromophore has been synthesized. Reaction of Zn(NO3)2 with Htzbc ligand in 1-n-butyl-3-methylimidazolium tetrafluoroborate ionic liquid afforded compound Zn(tzbc)2 (1). The Htzbc organic solid and 1 crystallize in the acentric Pn and Cc space groups, respectively. The tetrahedral Zn2+ center in 1 coordinates to two triazole nitrogen atoms and two carboxylate oxygen atoms from four tzbc– ligands, leading to a noncentrosymmetric 5-fold interpenetrating diamondoid network. Second-harmonic generation (SHG) measurements revealed the Htzbc solid and 1 have SHG activities. The Htzbc compound has a large SHG effect, which is approximately 3 times that of KDP and is type-I phase matchable, while 1 also belongs to phase-matchable class with a SHG response of about 1.2 times that of KDP. The SHG active of the organic solid can be derived from the inherently dipolar Htzbc molecule as well as the optimal relative orientation of the molecular NLO-phores in the crystal packing. The odd number-fold interpenetrated diamondoid network with dipolar NLO chromophoric units based on asymmetrical bridging ligands and metal centers results in the SHG activity of 1. In addition, elemental analysis, IR spectra, powder X-ray diffraction patterns (PXRD), and thermogravimetric analysis of both compounds are described.