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The effect of pedestrian and bicycle infrastructure is used to analyze the capacity for right-turn lane at signalized intersection. Each cycle at the signalized intersection was divided into several periods. The effect of pedestrian and bicycle at each period was analyzed. The number of right-turn cars going through signalized intersection was calculated by using probability theory and mathematical statistics. The capacity under the effect of pedestrian and bicycle for right-turn lane at signalized Intersection was deduced. The calculated results were deduced by using the survey data of two signalized intersections at Jinan city. The mean difference values are 8% and 10.1%, compared with VISSIM simulation results. The comparisons show that this model can fully describe the effect of pedestrian and bicycle to signalized intersection.

The X-ray Fluorescence Spectrometry (XRF) method was adapted for the determination of 10 major elements, such as silicon, aluminum, calcium and magnesium, in different types of rocks. The calibration curves were determined from 28 different types of rock standards which were fused into glass beads. The matrix effect was calibrated by using empirical factors. This method was used for determining the 10 major elements of samples from GeoPT proficiency testing. The 23 types of rock samples were analyzed over 15 years and the results indicate that this method is most effective in determining SiO2, Al2O3, K2O and CaO with the obtained|Z| < 2 for all samples. This method is also suitable for determining MgO, MnO, TiO2 and Na2O although each element has only one suspect result in different samples with the obtained|Z|>2, which was caused by the matrix difference between samples and standard samples in measuring the lower content elements. When the content of TFe2O3 is higher than 1.00% and P2O5 between 0.08% and 0.80%, the results can match expectations (the obtained|Z| < 2). To sum up, the developed XRF method has long term stability and is effective, which can match the expectation of applied geochemistry laboratories for determination of 10 major elements in different types of rock samples.

In this paper, we present the methods of parametrically reconstructing the position of a 3D scattering center model of the targets from SAR images for a target recognition application. First, a framework for reconstructing the 3D position of the targets from the SAR images is proposed. Then, a method that uses the parameters obtained from the scattering center of the targets from the SAR images is used for reconstructing the 3D scattering center model. Finally, the proposed methods are confirmed using the simulated data.

The accuracy of the certified values of the national reference materials plays an important role in instrument calibration, and therefore quality control for analysis data. In order to test the accuracy of the certified values of the Chinese National Standard Reference Materials, 36 trace elements were determined for 18 National Standard Reference Materials of rock (from GBW 07103 to GBW 07125), 19 National Standard Reference Materials of sediment (from GBW 07301 to GBW 07318) and 19 National Standard Reference Materials of soil (from GBW 07401 to GBW 07430) by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS). These National Standard Reference Materials were digested by using the pressurized acid digestion technique. The relative standard deviation (RSD) of most trace elements in these materials were typically better than 10%, except for Ni, Cr, Pb, Co, Cu, Sc, Yb and Lu in several reference materials. Most of the results were consistent with the certified values in the literature, and with a relative error of less than 10%. Results given here indicate that a few certified values of some reference materials should be revised. In addition, content values of some trace elements in the National Standard Reference Materials of sediment or National Standard Reference Materials of soil, such as Ni for GBW 07306, Be, Hf and Ta for GBW 07313, Li and Be for GBW 07314, Hf and Ta for GBW 07409, GBW 07410 and GBW 07411, Gd and Ta for GBW 07426 are provided here.

MOFs with semiconducting behavior exhibit unique optoelectronic properties, and they are hailed as future low-bandgap materials, which are expected to serve as a new generation of functional materials to solve some thorny problems in the field of environment and energy. In this work, eight semiconducting MOFs with chemical formulae, {[Cd(m-bix)(ATP)]}n (1), {[Zn2(m-bix)(ATP)2]·DMF}n (2), {[Cd(m-bix)(BDC)(H2O)]}n (3), {[Co2(m-bix)(BDC)2(H2O)3]·2H2O·CH3OH}n (4), {[Ni2(m-bix)(BDC)2(H2O)3]·2H2O·CH3OH}n (5), {[Cd(m-bix)(Cl)]}n (6), {[Zn(m-bix)(CO3)]}n (7), and {[Cd(FDC)(H2O)3]·2H2O}n (8) (m-bix = m-bis(imidazol-1-ylmethyl)benzene; H2ATP = 2-aminoterephthalic acid; H2BDC = p-phthalic acid; H2FDC = 2,5-furandicarboxylic acid), were successfully synthesized by hydrothermal techniques. Comprehensive characterization of the as-synthesized MOFs showed that they display interesting topologies and fascinating structures (of 6 and 8 being 1D, 1, 2, 3, and 7 being 2D and 4 and 5 being 3D). The incorporation of π-conjugated ligands and abundant intermolecular hydrogen bonds endows these MOFs with higher carrier transport rates, resulting in unique optoelectronic properties. The optical band gaps of MOFs 1–8 obtained by UV reflection spectroscopy were 2.86, 2.59, 3.91, 3.01, 3.69, 3.19, 3.09, and 3.87 eV, respectively, proving that they are all potential semiconductor materials. Electrochemical oxygen evolution reaction (OER) catalysis studies revealed that MOFs 4–5 are efficient catalysts for the OER process with lower overpotentials of 381 and 397 mV at 10 mA cm−2 and lower Tafel slopes of 75.1 and 74.4 mV dec−1. Photoluminescence studies demonstrated that the Cd-based and Zn-based MOFs, especially MOF 2, exhibit strong violet light emission properties in the range of 405–446 nm, which are expected to be used in the development of new luminescent materials. In addition, the photocatalytic performance of these MOFs was evaluated. Among them, the best photocatalytic performance of 4 and 6 was attributed to the combination of the band gap value and luminescence performance, resulting in more photogenerated carriers and thus more catalytically active sites. This work not only provides a certain theoretical and experimental basis for further research on the optoelectronic properties of MOFs, but also affords an advanced strategy for the development of novel multifunctional materials to solve real-life environmental and energy problems. [ABSTRACT FROM AUTHOR]

In order to solve the problems of environmental pollution and energy crisis, it is of great significance to develop low-cost, high-efficiency and environmentally friendly multifunctional materials to deal with environmental and energy concerns. Herein, two multifunctional Cu(II) coordination complexes with the formula {[Cu(m-bix)(FDC)(H2O)]·H2O}n (1) and {[Cu2(DAP)4(NIP)2]·DMF}n (2) (m-bix = m-bis(imidazol-1-ylmethyl)benzene; DAP = N-(4-pyridyl)dimethylamine; H2FDC = 2,5-furandicarboxylic acid; H2NIP = 5-nitroisophthalic acid) were successfully constructed by using mixed ligands via a solvothermal method. Structural analyses show that both complexes exhibit a 1D chain structure, extending into a 3D supramolecular network via abundant hydrogen bonding forces. Electrochemical oxygen evolution reaction (OER) catalytic studies reveal that 1 and 2 are efficient electrocatalysts for the OER. In particular, 2 has a lower overpotential of 360 mV at 1 mA cm−2 under alkaline conditions. Furthermore, both complexes exhibit excellent photocatalytic activity due to their narrow band gaps – 2.51 eV (494 nm) for 1 and 2.77 eV (448 nm) for 2. The oxidation system composed of the complex and H2O2 can degrade methyl orange azo dyes (40 mg L−1) to less than 10% in only 150 minutes under sunlight irradiation. This work demonstrates that employing mixed ligands is a promising approach to obtain multifunctional complexes. It also opens up a unique path for the development of high-efficiency, low-cost, and environmentally friendly multifunctional materials to address environmental and energy issues. [ABSTRACT FROM AUTHOR]

Mesenchymal stem cells (MSCs) are a new therapeutic strategy for inflammatory bowel disease (IBD), and their efficacy has been widely recognized. However, there are still some challenges in cell therapy, including stable cell passage, laboratory conditions for cell culture, high-cost burden, and poor transplantation. The conditioned medium (CM) of MSCs is considered be an excellent alternative to cell transplantation, but the paracrine group in MSC-CM is limited in variety and low in concentration, which cannot meet the therapeutic needs of injured tissues and needs to be optimized. Pretreatment with low concentration of hydrogen peroxide (H2O2) can not only protect cells from oxidative damage, but also play a role similar to growth factors and regulate the physiological function of stem cells, to obtain an improved conditioned medium. To determine the optimal protocol for pretreatment of MSCs with H2O2, and to study the efficacy and potential mechanism of MSC-CM pretreated with H2O2 on Dextran Sulfate Sodium (DSS)-induced acute experimental colitis. MSCs were exposed to different concentrations of H2O2, and the optimal H2O2 pretreatment conditions were determined by evaluating their critical cell functional properties. H2O2-pretreated MSC-CM was transplanted into experimental mouse colitis by enema at 2, 4, and 6 days in modeling, and the changes of colonic tissue structure, the levels of inflammation and oxidative stress, the molecular changes of Nrf2/Keap1/ARE axis, and the related indicators of apoptosis in colonic epithelial cells were observed in each group. In vitro, Pretreated MSCs with 25 μM H2O2 significantly enhanced cell proliferation, migration, and survival, but had no effect on apoptosis. In vivo, MSC-CM treatment decreased apoptosis and extracellular matrix deposition, and maintained the mechanical barrier and permeability of colonic epithelial cells in experimental mouse colitis. Mechanistically, H2O2-pretreated MSC-CM against reactive oxygen species (ROS) production and MDA generation, accompanied by increases in components of the enzymatic antioxidant system includes SOD, CAT, GSH-PX, and T-AOC, which is through the up-regulation of the Nrf2, HO-1, and NQO-1 antioxidant genes. Our data confirmed that 25 μM H2O2 pretreated MSC-CM treatment could effectively improve intestinal mucosal repair in experimental colitis, which may be achieved by activating Nrf2/Keap1/ARE pathway. [ABSTRACT FROM AUTHOR]