A More Efficient Method for Preparing a MIP-CQDs/ZnO1-x Photodegradant with Highly Selective Adsorption and Photocatalytic Properties.

The application of semiconductor photocatalysts in wastewater treatment always has a drawback, which is the lack of selectivity for pollutants, but molecular imprinting technology (MIT) is a remarkable method for preparing highly selective adsorbents for low concentration target pollutants. Up to now, the research of molecular imprinting materials has mainly focused on organic polymers, and there has been little research on inorganic molecular imprinting materials. In the present work, we introduced carbon quantum dots (CQDs) into the flower-like hierarchical ZnO to prepare photocatalysts CQDs/ZnO. Further, with ciprofloxacin (CIP) as the template molecule, a molecular imprinting material MIP-CQDs/ZnO1-x was prepared by introducing both oxygen vacancies and imprinted cavities into CQDs/ZnO by the hydrothermal calcination method. It can not only increase the concentration of oxygen vacancies and broaden the light absorption range of zinc oxide without changing the crystal form of ZnO but also make it have the characteristics of preferential adsorption and degradation of CIP during the degradation process. Under the synergistic effect of CQDs, oxygen vacancies, and molecularly imprinted cavities, the molecularly imprinted material exhibits excellent photocatalytic and selective adsorption performance.

Metallization on Sapphire and Low-Temperature Joining with Metal Substrates.

To meet the packaging requirements of sapphire in special electronic components, there is an urgent need for a joining process that can realize a good connection between sapphire and dissimilar metals at a low temperature. In this work, the surface of a sapphire substrate was successfully catalytically activated and metallized by an electroless nickel plating process. Moreover, the solderability and interconnection of metallized sapphire with Sn-based solders were evaluated and investigated at 250 °C, and the wetting angle of the Sn-based solders on sapphire on sapphire without and with metallization was 125° and 51°, respectively. The interfacial microscopic morphology and element distribution in the Cu/Sn-Ag solder/sapphire solder joints were analyzed. It was found that the middle solder layer has diffused during the reflow process, inferring good adhesion between sapphire and Cu substrate with the aid of the Ni-P deposition. Thus, a sapphire welding method with a simple process suitable for practical applications is demonstrated.

[Effect of autophagy regulator on the injury of rat hippocampal neurons induced by oxygen-glucose deprivation].

OBJECTIVE: To explore the effect of autophagy regulator on the injury of rat hippocampal neurons induced by oxygen-glucose deprivation (OGD). METHODS: Rat hippocampal neurons were cultivated in primary and subjected to OGD to simulate neuronal hypoxic ischemia injury for 2 hours or 6 hours followed by reperfusion for 12 hours with or without 3-methyladenine (3-MA, 20 µmol/L) or rapamycin (0.2 µmol/L). The morphology of neurons was observed with optical microscope. The expression of autophagy-related protein (LC3, P62) and apoptosis-related protein (cleaved caspase-3) were assessed by Western Blot analysis. The apoptosis of neurons was detected by flow cytometry, the release rate of lactate dehydrogenase (LDH) was calculated by automatic biochemical analyzer, and the cell activity was determined by methyl thiazolyl tetrazolium (MTT) colorimetric assay. RESULTS: Compared with the control group, the expression of LC3 II/I (gray value: 3.091±0.160, 3.422±0.186 vs. 0.256±0.021), cleaved caspase-3 (gray value: 0.230±0.025, 0.440±0.051 vs. 0.050±0.007), neuronal apoptotic rate, LDH release rate [(38.50±4.15)%, (59.60±5.65)% vs. (12.40±1.32)%] were increased, while the expression of P62 (gray value: 0.290±0.025, 0.120±0.026 vs. 0.450±0.040), neuronal activity [(71.40±7.23)%, (42.80±4.12)% vs. (100.30±2.30)%] were decreased at 2 hours or 6 hours after OGD (all P < 0.05). When the time of OGD was 2 hours and it was combined with 3-MA, the expression of LC3 II/I (gray value: 2.281±0.121), the neuronal activity [(51.10±5.73)%] were decreased, while the expression of P62 and cleaved caspase-3 (gray scale: 0.410±0.037, 0.330±0.027, respectively), neuronal apoptotic rate, the injury of neurons [LDH release rate: (47.30±4.43)%] were increased (all P < 0.05). When the time of OGD was 2 hours and it was combined with rapamycin, the expression of LC3 II/I (gray value: 3.689±0.214), the neuronal activity [(85.30±8.56)%] were increased, while the expression of P62 and cleaved caspase-3 (gray value: 0.170±0.040, 0.090±0.096, respectively), neuronal apoptotic rate, the injury of neurons [LDH release rate: (24.30±2.14)%] were decreased (all P < 0.05). On the contrary, when the time of OGD was 6 hours and it was combined with 3-MA, the expression of LC3 II/I and cleaved caspase-3 (gray value: 3.021±0.178, 0.240±0.017), neuronal apoptotic rate, the injury of neurons [LDH release rate: (36.60±3.45)%] were decreased, while the expression of P62 (gray value: 0.350±0.060), the neuronal activity [(59.70±6.13)%] were increased (all P < 0.05). When the time of OGD was 6 hours and it was combined with rapamycin, the expression of LC3 II/I and cleaved caspase-3 (gray value: 3.923±0.201, 0.590±0.062), neuronal apoptotic rate, the injury of neurons [LDH release rate: (71.20±7.81)%] were increased, while the expression of P62 (gray value: 0.070±0.008), the neuronal activity [(27.30±2.12)%] were decreased (all P < 0.05). CONCLUSIONS: The enhancement of autophagy has protective effect on neurons under the condition of mild OGD, while it can aggravate the injury of neurons induced by a long-time OGD.