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A water-stable Zn-MOF was constructed based on H2PBA and 1, 10-phenanthroline under solvothermal conditions. The compound exhibited a 3D (2,3,8)-connected (43)2(46.66.815.12)(8) topology framework. The crystal structure and phase purity of the compound was verified by single crystal X-ray diffraction. Subsequently, some studies on the morphology, structure, and luminescent properties were carried out. The results showed that this compound could be used as a versatile chemosensor for Fe3+/Cu2+, trinitrophenol and colchicine via a luminescence quenching effect in an aqueous medium. [ABSTRACT FROM AUTHOR]

Searching for new low-dimensional organic–inorganic hybrid phosphors is of great significance due to their unique optical properties and wide applications in the optoelectronic field. In this work, we report a Mn4+ doped zero-dimensional organic–inorganic hybrid phosphor [N(CH3)4]2ZrF6, which was synthesized by a wet chemical method. The crystal structure, thermal stability, and optical properties were systemically investigated by means of XRD, SEM, TG-DTA, FTIR, DRS, emission spectra, excitation spectra, as well as decay curves. Narrow red emission with high color purity can be observed from [N(CH3)4]2ZrF6:Mn4+ phosphor, which maintains effective emission intensity even at room temperature, indicating its potential practical application in WLEDs. In the temperature range of 13–295 K, anti-Stokes and Stokes sidebands of Mn4+ ions exhibit different temperature responses. By applying the emission intensity ratio of anti-Stokes vs. Stokes sidebands as temperature readout, an optical thermometer with a maximum absolute sensitivity of 2.13% K−1 and relative sensitivity of 2.47% K−1 can be obtained. Meanwhile, the lifetime Mn4+ ions can also be used for temperature sensing with a maximum relative sensitivity of 0.41% K−1, demonstrating its potential application in optical thermometry. [ABSTRACT FROM AUTHOR]

Ce3+/Tb3+ co‐doped NaMgBO3 phosphors were successfully synthesized by solid‐state method. Under 381 nm excitation, the cyan emission owing to the 5d → 4f of Ce3+ ions and green emissions arising from the 5D4 → 7FJ (J = 6, 5, 4, and 3) transitions of Tb3+ ions were seen in all the phosphors. Through theoretical analysis, one knows that the energy transfer from Ce3+ to Tb3+ ions with high efficiency of 83.74% was contributed by dipole–dipole transition. Furthermore, the internal quantum efficiency of NaMgBO3:0.01Ce3+,0.03Tb3+ phosphor was 54.28%. Compared with that of at 303 K, the emission intensity of the developed products at 423 K still kept 73%, revealing the splendid thermal stability of the studied phosphors. Through utilizing the resultant phosphors as cyan‐green components, the fabricated white‐LED device exhibited an excellent correlated color temperature of 2785 K, high color‐rendering index of 85.73, suitable luminance efficiency of 25.00 lm/W, and appropriate color coordinate of (0.4279, 0.3617). Aside from the superior photoluminescence, the synthesized phosphors also exhibited excellent cathode‐luminescence properties which were sensitive to the current and accelerating voltage. Furthermore, the NaMgBO3:0.01Ce3+,0.03Tb3+ phosphors with multi‐mode emissions were promising candidates for optical anti‐counterfeiting. All the results indicated that the Ce3+/Tb3+ co‐doped NaMgBO3 phosphors were potential multi‐platforms toward white‐LED, field emission displays, and optical anti‐counterfeiting applications. [ABSTRACT FROM AUTHOR]

Ethylene glycol (EG)-based hybrid nanofluids containing graphene oxide–silver nanosheets (GO–Ag) were simply prepared without using any surfactant. The graphene oxide–silver composites were characterized using X-ray diffraction analysis, transmission electron microscope, infrared and UV–visible spectroscopy. The stability of GO–Ag nanofluids was estimated by UV–visible spectroscopy. The GO–Ag/EG hybrid nanofluids has good stability without significant sedimentation for 60 days. A few thermophysical properties of GO–Ag/EG nanofluids with 0.1, 0.2 and 0.3 wt% nanosheets were analysed experimentally at different temperatures ranging from 20 to 50°C. [ABSTRACT FROM AUTHOR]

In order to improve the accuracy of load forecasting, eliminate the correlation between multi-meteorological factors and eliminate redundancy, a load forecasting method based on GOA-LSSVM is proposed. Firstly, the principal component analysis is used to express the data dimension reduction and characteristics of load influencing factors, and the main influencing factors are determined. Then, based on the influence of parameter combination of C and G, the LSSVM model parameters are selected by Grasshopper optimization algorithm. The results show that compared with GOA-LSSVM and LSSVM, this algorithm can effectively improve the accuracy of load prediction, and can eliminate the correlation between data redundancy and influencing factors through data reduction and feature representation. It simplifies the complexity of load prediction model, and also the speed of prediction model is improved, which proves the validity and reliability of this algorithm. [ABSTRACT FROM AUTHOR]

KBaY(MoO4)3 : Eu3+ phosphors were synthesized using high temperature solid state method, and their structure, morphology and luminescent properties were characterized by means of X-ray diffraction (XRD), scan electron microscope (SEM), luminescent spectra and luminescent decay curves. The results of XRT) showed that the XRI) patterns of KBaY(MoO4)3 : Eu3+ were consistent with those of pure KBaY(MoO4)3 and the Y<3+ ions could be completely substituted by Eu3+ ions without damaging the structure of KBaY(MoO4)3. The excitation spectra showed that KBaY(MoO4)3 : Eu3+ exhibited an intensive excitation band at 394 nm, which meant the KBaY(MoO4)3 could be effectively excited by NUV LED. According to the luminescent spectra, in the v matrix, the optimum concentration of Eu3+ ions was up to 90%, indicating that the concentration quenching effect was weak for the KBaY(MoO4)3 : Eu3+. The emission intensity decreased with the increasing of temperature. As the temperature reached to 200 °C, the emission intensity of the sample was about 63% of that at 30 °C, and the activation energy of KBaY(MoO4)3 : Eu3+ was calculated to be 0.261eV through fitting the curves of ln(I0C/IT - 1)-1/kT. [ABSTRACT FROM AUTHOR]

Defective TiO has attracted increasing attention for use in photocatalytic and electrochemical materials because of its narrowed band-gap and improved visible-light photocatalytic activity. However, a facile and efficient approach for obtaining defect-rich TiO still remains a challenge. Herein, we demonstrate such an approach to narrow its bandgap and improve visible-light absorption through implanting abundant defects by aerodynamic levitated laser annealing (ALLA) treatment. Note that the ALLA method not only provides rapid annealing, solidifying and cooling process, but also exhibits high efficiency for homogeneous and defective TiO nanoparticles. The laser-annealed TiO achieves a high hydrogen evolution rate of 8.54 mmol·h·g, excellent decomposition properties within 60 min, and outstanding recyclability and stability, all of which are superior to the corresponding properties of commercial P25. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Needle knife precut sphincterotomy (PS) during endoscopic retrograde cholangiopancreatography (ERCP) has been associated with a high risk of post-ERCP pancreatitis (PEP). This study aimed to examine the effect of no prophylaxis, somatostatin, rectal diclofenac and pancreatic duct (PD) stenting in reducing rates of PEP in patients who underwent early PS. METHODS: This was a retrospective comparative study and the study period was from January 2006 to December 2015. A standardized approach to early PS was used: (i) inadvertent guidewire cannulation of the PD>thrice; (ii) impacted bile duct stone; (iii) inability to achieve deep cannulation within 10 min. PEP prophylactic measures included: (i) none when there was minimal papilla trauma; (ii) somatostatin infusion; (iii) rectal diclofenac; (iv) PD stent. The difference in rates of PEP between the different strategies was analysed. RESULTS: During the study period, PS was performed in 191 ERCP patients (mean age 66 years; 56.5% males). The ERCP success rate after PS was 93.2% (178/191). Overall the PEP rate was 3.1% (6/191) and the severity in all cases was mild. PEP occurred in 6.1% of patients with PD cannulation but not in those without (P = 0.016). PEP rates were 1.8%, 7.3%, 1.8% and 0% in control, somatostatin, diclofenac and PD stenting groups, respectively (P = 0.209). CONCLUSIONS: There was no significant difference in PEP rates after early PS whether or not prophylactic measures were adopted if there was minimal papilla trauma. A trend towards lower PEP rates was observed in patients who had either rectal diclofenac or PD stenting, compared to somatostatin. [ABSTRACT FROM AUTHOR]

Vasculitis is an inflammation that can present as acute or chronic in nature, which causes changes in the walls of blood vessels, including thickening, weakening, narrowing and scarring. Gemcitabine, an antimetabolite chemotherapeutic agent, is generally well tolerated with a favorable side effect profile. However, there is increasing evidence that it is associated with vasculitis, which can affect small and large vessels. In this case report, we report a patient who has experienced fever with severe tenderness over right carotid artery, which occurred on the fifth day after the administration of gemcitabine. The exact mechanism of gemcitabine-induced vasculitis is unknown but cessation of gemcitabine and initiation of anti-inflammatory treatment appears to aid in the resolution of the clinical syndrome. [ABSTRACT FROM AUTHOR]

Background and Aim Clarithromycin-based triple therapy ( TT) is the first-line treatment for Helicobacter pylori infection in Singapore. There is awareness that TT may no longer be effective due to increased clarithromycin resistance rates. Sequential therapy ( ST) and concomitant therapy ( CT) are alternative treatment regimens. This study aimed to compare the efficacy of 10-day TT, ST, and CT as first-line treatment for H. pylori infection. Methods A randomized study conducted in a teaching hospital. Patients aged 21 years and older with newly diagnosed H. pylori infection were randomized to 10-day TT, ST, or CT. Treatment outcome was assessed by 13-carbon urea breath test at least 4 weeks after therapy. Intention to treat ( ITT), modified ITT ( MITT), and per protocol ( PP) analyses of the eradication rates were performed. Results A total of 462 patients were enrolled ( ST: 154; TT 155; CT 153). Patient demographics were similar. Eradication rates for ST versus TT versus CT: ITT analysis: 84.4% versus 83.2% versus 81.7% ( P = not significant [ NS]); MITT analysis: 90.3% versus 92.1% versus 94.7% ( P = NS); PP analysis: 94.1% versus 92.8% versus 95.4% ( P = NS). Antibiotic resistance rates for amoxicillin, clarithromycin, and metronidazole were 4.7%, 17.9%, and 48.1%, respectively. Dual clarithromycin and metronidazole resistance occurred in 7.5%. Dual resistance and lack of compliance were predictors of treatment failure. Conclusions TT, ST, and CT all achieved eradication rates above 80% on ITT and above 90% on MITT and PP analyses. Dual resistance and lack of compliance were predictors of treatment failure (clinicaltrials.gov: NCT02092506). [ABSTRACT FROM AUTHOR]

In order to solve the common problems in existing solar greenhouses such as simple equipment, poor environmental regulation and cold prevention ability, as well as low land utilization rate and labor productivity, a new type of greenhouse, the assembly type solar double effect greenhouse was built and researched. There are two kinds of structures for the assembly type of the solar double effect greenhouse: internal insulation greenhouse and external insulation greenhouse. Internal insulation warehouse has two layer frames with single layer film covering each layer frame, in addition, one layer of heat preservation quilt is placed between the two layer frames to insulate and preserve heat energy during the night. The external insulation greenhouse has a structure of transparent Polycarbonate sandwich plate as its back half roof and back wall. In winter time, thermal insulation material is filled in the interlayer to preserve heat, in the meantime, the heat preservation quilt is covered on the front half roof, it changed the old way of an opaque back wall and an opaque back half roof in the previous greenhouse. Both the internal and the external insulation greenhouses are fully transparent greenhouses with galvanizing steel structures as framework. A solar energy source heat pump system is assembled in the greenhouse, it includes a solar heat collector, thermal storage pool and the heat pump, with water as its medium, it uses the solar heat collector to convert solar energy into heat energy and it is stored in thermal storage pool. When it is cold, the solar heat collector converts the heat energy stored in the heated water to the greenhouse. When the stored heated water is too cold to provide heat energy, the heat pump is started to convert the low grade heat energy to high grade heat energy, to provide heat energy to the greenhouse. The heat pump can also convert the steam and redundant heat energy in the air into heated water and it is stored in the thermal storage pool, so as to adjust the air temperature and moisture in the greenhouse automatically thus achieving double effects. In this paper, insulation moisture performance and the yield increasing effect are mainly researched for the assembly type of the solar double effect greenhouse. The test was processed from Dec. 2012 to Jan. 2013. The main test indexes are, air minimum temperature, daily average temperature, light intensity, relative air humidity, crops yield per plant and yield per unit area. The test results show: For the internal insulation greenhouse, the minimum temperature of the testing greenhouse was always over 9°C . Compared to the reference greenhouse, during Jan. 2013, the average temperature increased 3.4°C, the monthly average minimum temperature increased 4.0°C, and the monthly average relative air humidity was below 80%, thus achieved a 70% reduction in the incidence of vegetables. For the external insulation greenhouse, the average minimum temperature of the testing greenhouse was 12.5°C, the relative air humidity was below 80%, and the average temperature increased 3.8°C compare to the reference greenhouse. The temperature was 27.7°C higher than outside of the greenhouse (-15.2°C), the yield of the planting vegetables increased 19% - 55%. The conclusion is, the assembly type of the solar double effect greenhouse improved environmental conditions greatly, and improved the capacity of both cold and disease prevention, and increased both production and income. The research and application of this new type of greenhouse are referenced for similar areas in northern China. [ABSTRACT FROM AUTHOR]

In this paper, a unique approach for road extraction utilizing pixel spectral information for classification and image segmentation -derived object features was developed. In this approach, road extraction was performed in two steps. In the first step, support vector machine (SVM) was employed merely to classify the image into two groups of categories: a road group and a non-road group. For this classification, support vector machine (SVM) achieved higher accuracy than Gaussian maximum likelihood (CML). In the second step, the road group image was segmented into geometrically homogeneous objects using a region growing technique based on a similarity criterion, with higher weighting on shape factors over spectral criteria. A simple thresh olding on the shape index and density features derived from these objects was performed to extract road features, which were further processed by thinning and vectorization to obtain road centerlines. The experiment showed the proposed approach worked well with images comprised by both rural and urban area features. [ABSTRACT FROM AUTHOR]

An Mg-doped isotope lithium niobate (Mg:7LiNbO3) crystal was successfully grown from 7LiOH, Nb2O5, and MgO using the Crozchralski method. The weight of the as-grown crystal with good quality was about 40 g. The crystal structure was determined as an R3c space group using the X-ray powder diffraction (XRPD) method, and the crystal composition (Li%) determined using the Raman mode linewidth method was 49.29%. The average transmittance of the crystal in the range of 500–2500 nm was approximately 72%. Various thermal properties, including the specific heat (Cp), the thermal expansion coefficient (α), the thermal diffusion coefficient (λ), and the thermal conductivity (κ), were carefully determined and calculated, and the value divergences among Mg:7LiNbO3, the undoped isotope lithium niobate (7LiNbO3), and natural lithium niobate (LiNbO3) crystals were mainly related to the differences in microstructure caused by the crystal composition. [ABSTRACT FROM AUTHOR]