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In this paper, two types of solid phase 2D and 3D XBOFs were selectively constructed from identical building blocks of tetraphenylmethane tetrapyridine derivative and 1,4-diiodotetrafluorobenzene by changing the crystallization solvent. This 3D XBOF is a novel hybrid supramolecular organic framework with the synergistic control of hydrogen and halogen bonds. [ABSTRACT FROM AUTHOR]

The molar heat capacities of one-three-dimensional metal-organic frameworks Al4(OH)2(OCH3)4(H2N-BDC)3 (CAU-1) were measured by temperature-modulated differential scanning calorimetry (TMDSC) over the temperature range from 213 to 393 K for the first time. No phase transition or thermal anomaly was observed in the experimental temperature range. The fundamental thermodynamic parameters such as entropy and enthalpy relative to 298.15 K were calculated based on the experimentally determined molar heat capacities. The compound was characterized by elemental analysis, powder XRD, FT-IR spectrum. Moreover, the thermal stabilities and decomposition mechanisms of hydrated phase and dehydrated phase of CAU-1 were investigated by thermogravimetric spectrometer in the temperature range 298-1023 K. [ABSTRACT FROM AUTHOR]

Constitutive model plays an important role in the numerical simulations of metal forming. However, the influence of the models on the calculation is vague. Based on the stress-strain data of Al 7050 and Ti-6Al-4V alloys generated by isothermal compressive tests, the Johnson-Cook (JC) and Arrhenius-type (A-type) hyperbolic sine models were fitted to obtain the constants. Flow stresses directly calculated by the equations were compared with the experiment results, and rigid-plastic finite element analyses (FEA) utilizing these models were employed to simulate the same compression processes. The results show that A-type model has higher accuracy in the direct prediction of flow stress, even outside of the fit domain. The simulation results using A-type model also have higher agreement with the experiment; however, the suitability is affected by the referential parameters employed in the regression process. In terms of the overall deformation and strain distributions, there are slight differences among the simulation results using these two models. [ABSTRACT FROM AUTHOR]

We aim to develop novel photoresponsive surface molecularly imprinted polymer (SIMP) microspheres, an SiO2-SIMP, for the photocontrolled extraction of uric acid from biological samples. The SiO2-SMIP was prepared on silica microspheres by surface polymerization and characterized by using scanning electron microscopy, transmission electron microscopy, FTIR spectroscopy, thermogravimetric analysis, nitrogen adsorption-desorption analysis, and UV-visible spectroscopy. The SiO2-SMIP microspheres showed a photocontrolled uptake and release of uric acid in NaH2PO4 buffer upon alternate irradiation at 365 and 440 nm. The SiO2-SMIP microspheres were able to photocontrollably extract uric acid from complicated biological samples for concentration analysis with no significant interference encountered and it exhibited very good recognition ability and fast binding kinetics toward uric acid. [ABSTRACT FROM AUTHOR]

Abstract: A new type of chiral copper complexes of N,P-ferrocenyl ligands with central and planar chirality as efficient catalyst was applied to the enantioselective addition of diethylzinc to N-diphenylphosphinoylimines. The (R)- and (S)-enantiomers of the addition reaction were obtained for this transformation. In the presence of 6mol% of bidentate ligand 1 and 12mol% of Cu(OTf)2, the asymmetric addition process affords N-diphenylphosphinoylamides in up to 97% ee and 95% yields. [Copyright &y& Elsevier]

Lycium barbarum polysaccharides (LBP) are derived from Wolfberry and have antioxidant activities. This study aimed to evaluate the efficacy of LBP for kidney injury in a rat model of sepsis. Male rats were divided randomly to control group (Con), LPS group (LPS), ulinastatin group (ULI), low dose LBP group (LBP-1), middle dose LBP group (LBP-2) and high dose LBP group (LBP-3). After intraperitoneal injection of LPS (5 mg/kg) to make sepsis model (LPS group), 10,000 U/kg ulinastatin were given in ULI group, and 200, 400 and 800 mg/kg LBP was given in LBP-1, -2, -3 group, respectively. Serum IL-1β, IL-6, IL-8, TNF-α and NF-κB levels were measured by ELISA. Nrf2, Keap1, NF-κB, HO-1 and NQO1 expression levels were detected by PCR and Western blot analysis. We found that LBP decreased the levels of NF-κB and pro-inflammatory cytokines while attenuated kidney injury. In addition, LBP regulated Keap1-Nrf2/ARE signaling pathway in the kidney. In conclusion, LBP attenuates inflammation injury in the kidney via possible regulation of Keap1-Nrf2/ARE signaling. [ABSTRACT FROM AUTHOR]

It is recognized that the cerebral ischemia/reperfusion (I/R) injury triggers inflammatory activation of microglia and supports microglia-driven neuronal damage. Our previous studies have shown that ginsenoside Rg1 had a significant protective effect on focal cerebral I/R injury in middle cerebral artery occlusion (MCAO) rats. However, the mechanism still needs further clarification. Here, we firstly reported that ginsenoside Rg1 effectively suppressed the inflammatory activation of brain microglia cells under I/R conditions depending on the inhibition of Toll-likereceptor4 (TLR4) proteins. In vivo experiments showed that the ginsenoside Rg1 administration could significantly improve the cognitive function of MCAO rats, and in vitro experimental data showed that ginsenoside Rg1 significantly alleviated neuronal damage via inhibiting the inflammatory response in microglia cells co-cultured under oxygen and glucose deprivation/reoxygenation (OGD/R) condition in gradient dependent. The mechanism study showed that the effect of ginsenoside Rg1 depends on the suppression of TLR4/MyD88/NF-κB and TLR4/TRIF/IRF-3 pathways in microglia cells. In a word, our research shows that ginsenoside Rg1 has great application potential in attenuating the cerebral I/R injury by targeting TLR4 protein in the microglia cells. [ABSTRACT FROM AUTHOR]

Azobenzene-bridged cationic–neutral and cationic–cationic were synthesized, characterized and compared with azobenzene-bridged neutral–neutral materials. Azobenzene-bridged cationic–cationic and neutral–neutral materials exhibited well-defined and reversible redox couples during redox processes, good electrochromic behavior, and appropriate contrast ratios in the visible regions. However, azobenzene-bridged cationic–neutral materials exhibited a quasi-reversible electrochemical process. The electrochromic stability of these compounds is in the order: azobenzene-bridged neutral–neutral materials > azobenzene-bridged cationic–cationic materials > azobenzene-bridged cationic–neutral materials. Electrochromic devices based on azobenzene-bridged neutral–neutral materials achieved maximum optical contrast, fast response time, and high coloration efficiency. The substituents of azobenzene-bridged cationic–cationic materials and the anions of azobenzene-bridged cationic–neutral materials did not significantly influence their electrochemical properties and response time, but slightly affected the maximum optical contrast, change in optical density, and coloration efficiency. [ABSTRACT FROM AUTHOR]