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Hexagonal boron nitride nanosheets(BNNSs) were prepared by a facilechemical exfoliation method. Then cosolution film casting method wasused to obtain poly(butylene adipate) (PBA)/BNNSs nanocomposites.The incorporated BNNSs changed the formation condition of the polymorphiccrystals of PBA. The results of differential scanning calorimetry(DSC) and wide-angle X-ray diffraction (WAXD) showed that BNNSs significantlyfacilitated the formation of α-form crystals for isothermaland nonisothermal crystallization. Compared to pure PBA at 28 °C,the α-form crystals would not disappear until the temperaturedecreased to 13 °C with the addition of 0.5 wt % BNNSs. In addition,the excellent heterogeneous nucleation ability of BNNSs was identifiedby the nonisothermal and isothermal crystallization process. The enzymaticdegradation experiments exhibited that PBA/BNNSs nanocomposites possesseda considerably lower degradation rate than neat PBA. This work demonstratesthat BNNSs is an efficient material to regulate the formation of polymorphiccrystals and the degradation behavior of PBA. [ABSTRACT FROM AUTHOR]

The reaction of 3-(2,4-dicarboxyphenyl)-2,6-pyridinedicarboxylic acid (H4dppd) with rare earth nitrates under hydrothermal conditions generated a series of new two-dimensional (2D) coordination polymers, namely {[La(Hdppd)(H2O)2·(H2O)2]n (1), [Ln2(Hdppd)2(H2O)4·(H2O)3]n [Ln = Sm (2), Eu (3)] and [Ln(Hdppd)-(H2O)3·H2O]n [Ln = Gd (4), Tb (5), Dy (6), Ho (7), Er (8)] [Hdppd = 3-(2,4-dicarboxyphenyl)-2,6-pyridinedicarboxylic trivalent anion]}. The complexes were characterized by X-ray single-crystal diffraction, infrared spectroscopy, elemental analysis and thermogravimetric analysis. Luminescence spectroscopy of 3 and 5 showed bright red and green luminescences due to the 4fn-4fn transitions in Eu3+ and Tb3+ respectively, although the luminescence lifetime is shortened by non-radiative decay due to the presence of coordinating water molecules. The magnetic properties of 2-8 were measured and discussed. Compound 6 exhibits frequency dependent out-of-phase signals, and ferromagnetic coupling exists in 8. [ABSTRACT FROM AUTHOR]

The poly(ethylene glycol) (PEG, with M 2000)-urea inclusion compound (IC) crystallized at high temperature region showed two typical orientations, flat-on and edge-on crystals. 2D-XRD and polarized FTIR spectroscopy revealed that the PEG chains within urea channels were perpendicular to the substrate in flat-on oriented crystals, while PEG chain axes were parallel to the substrate and lay along the growth direction in the edge-on crystals. FTIR absorption bands of PEG in the ICs are sensitive to orientation of the crystals. A scheme of PEG chain packing in the urea IC channel was proposed, which could explain the orientation of the crystal nucleus causing the two types of morphologies. Furthermore, functioning of PEG2000 chain end with analine had significantly influence on the morphology and orientation of the inclusion compound crystals, due to the defects caused by large terminal groups included in the urea channel. [ABSTRACT FROM AUTHOR]

A family of lanthanide-organic frameworks, {Ln2(pyip)(ox)2.5(H2O)5}n (Ln = La (1), Pr (2), Sm (3), Eu (4), Gd (5), Tb (6), Dy (7)) has been synthesized based on mixed bridging ligands, H2pyip and oxalate anion (H2pyip = 5-(4-pyridyl)-isophthalic acid, H2ox = oxalic acid) and characterized by elemental analysis, Fourier transform infrared spectroscopy, steady state and time-resolved luminescence spectroscopy, thermogravimetric analysis, powder X-ray diffraction and single-crystal X-ray diffraction. The single-crystal X-ray diffraction analysis results show that complexes 1-7 are isostructural. They crystallize in the same P21/c space group and exhibit a (3,4)-connected {42.6.82.10}{82.10} topology, being a 2-nodal net topology. The luminescence properties of 3, 4, 6, and 7 were investigated and related to the structural properties. The magnetic studies reveal that strong ferromagnetic coupling exists in compound 6. [ABSTRACT FROM AUTHOR]

A series of new amphiphilic phosphonium materials that combine the electronic features of phospholes with self-assembly features of lipids were synthesized. Variable concentration/temperature and 2D NMR studies suggested that the systems undergo intramolecular conformation changes between a "closed" and "open" form that are triggered by intermolecular interactions. The amphiphilic features of the phospholium species also induce liquid crystalline and soft crystal phase behavior in the solid state, which was studied by differential scanning calorimetry (DSC), polarized optical microscopy (POM), and variable temperature powder X-ray diffraction (VT-PXRD). The studies revealed that both conjugated backbones and counteranions work together to organize the systems into different morphologies (liquid crystal/soft crystal). Dithieno[3,2-b:2',3'-d]phosphole-based compounds exhibit enhanced emission in the solid state and at low temperature in solution due to aggregation-induced enhanced emission (AIEE). Photoinduced electron transfer (PET) induced via the alkoxybenzyl group at the phosphonium center in the fused-ring systems can be effectively suppressed through intermolecular charge transfer (ICT) processes within the main scaffold of a nonfused system, which was confirmed by static and dynamic fluorescence spectroscopy. The dynamic features of these new materials also endow the systems with external-stimuli responsive photophysical properties that can be triggered by temperature and/or mechanical forces. [ABSTRACT FROM AUTHOR]

Background: Ovarian cancer is the second most common gynecologic malignancy. As the primary imaging modality, computed tomography (CT) can provide staging information for preoperative planning and determination of surgical resectability. As a new three-dimensional postprocessing tool for CT images, cinematic rendering (CR) has the potential to depict anatomic details accurately. Case presentation: (Case 1) A 44-year-old married woman was diagnosed with recurrent ovarian cancer. CT images indicated the recurrent nodules and masses in the pelvic cavity and the upper middle abdominal peritoneum. The CR image showed that the multiple metastatic lesions and lymph nodes could not be completely removed by reoperation. The patient agreed to receive continued chemotherapy. (Case 2) A 51-year-old woman was admitted to our hospital due to abdominal distension and defecation that had increased for 6 months, with aggravation over the past 3 days. CT examination found cystic and solid masses in the bilateral ovarian area. The CR image demonstrated that the ovarian mass violated the posterior wall of the bladder and the anterior rectal wall. The preoperational imaging evaluation ensured the safety of the operation. Conclusion: CR could improve the visualization of ovarian cancer masses, metastatic lymph nodes, and peritoneal metastases. CR has a good clinical value and will be more helpful in the preoperational evaluation of ovarian cancer. [ABSTRACT FROM AUTHOR]

Abstract: Electrochemical performance of Cu2MoS4 was evaluated. When the cutoff potential is limited between 1.6 and 3.0V, the material can give stable cycle performance of up to 100mAhg−1. However, the material shows slow kinetics within this region. The material can give a discharge capacity of up to 653mAhg−1 when discharged to 0.6V vs. Li/Li+, with a first cycle efficiency of 61.3%. This corresponds to an insertion of 8.5Li and an extraction of 5.2Li from the material. XRD and XPS measurements both suggest Cu displacement from the material during discharge and charge, which is a possible reason for the poor cycle stability of the material. A reaction mechanism is proposed based on the XPS analysis. Better cycle performance is observed for Cu2MoS4/GO composite. [Copyright &y& Elsevier]

Thin film of p-type cupric oxide ( p -CuO) is grown on silicon (n-Si) substrate by using chemical bath deposition (CBD) technique and a precise control of thickness from 60 nm to 178 nm has been achieved. The structural properties and stoichiometric composition of the grown films are observed to depend significantly on the growth time. The chemical composition, optical properties, and structural quality are investigated in detail by employing XRD, ellipsometric measurements and SEM images. Also, the elemental composition and the oxidation states of Cu and O in the grown samples have been studied in detail by XPS measurements. Thin film of 110 nm thicknesses exhibited the best performance in terms of crystal quality, refractive index, dielectric constant, band-gap, and optical properties. The study suggests synthesis route for developing high quality CuO thin film using CBD method for electronic and optical applications. [ABSTRACT FROM AUTHOR]

Abstract: The present study established a time-saving technique for hydrogen uptake measurements using a high-pressure thermo-gravimetric analyzer (HPTGA). The critical buoyancy effects were considered in the analysis model. The HPTGA technique developed here for metal–organic frameworks (MOFs) was validated through independent experiments. The room temperature (RT) hydrogen uptake of MOFs via spillover was significantly enhanced by use of a bridge-building treatment. MOF samples with different structural parameters and RT hydrogen uptake performance can be prepared and manipulated through various factors affecting their synthesis. The structural evolution of MOFs within various steps during the synthesis and bridge-building processes were investigated by electron microscopy, nitrogen sorption isotherm analysis, and powder X-ray diffraction. [Copyright &y& Elsevier]