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Surface-enhanced Raman scattering (SERS) is a very important tool in vibrational spectroscopy. The coupling of nanomaterials induces local surface plasmon resonance (LSPR), which contributes greatly to SERS. Due to its remarkable sensitivity in trace detection, SERS has gained prominence in the fields of catalysis, biosensors, drug tracking, and optoelectronic devices. SERS activity is believed to be closely related to the LSPR and charge transfer (CT) of the material. Noble metal nanostructures have been commonly used as SERS-active substrates due to their strong local electric fields and relatively mature preparation, application, and enhancement mechanisms. In recent years, SERS research based on semiconductor materials has attracted significant attention because semiconductor materials have advantages such as repeatable preparation, simple pretreatment, stable SERS spectra and superior biocompatibility, stability, and reproducibility. Semiconductor-based SERS has the potential to enrich SERS theory and applications. Thus, the development of semiconductor materials will introduce a new epoch for SERS-based research. In this review, we outline the two main kinds of semiconductor SERS-active substrates: inorganic and organic semiconductor SERS-active substrates. We also provide an overview of the SERS mechanism for different kinds of materials and SERS-based applications. [ABSTRACT FROM AUTHOR]

In this paper, Al/TiB2 + 10%Ti4O7/PbO2-xCeO2 composite electrode materials were prepared by thermal spraying technology and electrochemical deposition method. The microstructure of the coatings with different contents of Ce3+ was observed by scanning electron microscope, and the phase composition of the coatings was analyzed by X-ray diffractometer. The electrochemical properties of the electrodes were studied by Tafel, EIS, LSV, and CV. The results show that with the increase of Ce3+ concentration, the overall performance of the electrode is improved, but when the content exceeds 1.5 g/L, it will cause agglomeration and reduce the electrode performance. Therefore, when the Ce3+ concentration is 1.5 g/L, the comprehensive performance and effect of the electrode are the best. Moreover, it can be seen from the SEM image that after adding Ce3+, the grains are denser than that of the composite anode without addition. [ABSTRACT FROM AUTHOR]

Based on density functional theory, this paper uses first-principles methods to study the stability, electronic properties, anisotropy, thermodynamic properties, and optical properties of compound MB2 (M = V, Nb, Zr). The enthalpy of formation indicates that the compound MB2 is energy stable. Studying its electronic properties, it is concluded that the compound MB2 (M = V, Nb, Zr) has metallic properties from the band structure and density of states diagram. The analysis of the differential charge density shows that the binding force between B–M and M–M atoms is greater than that of B–B. The results of elastic performance research show that VB2, NbB2, and ZrB2 exhibit brittleness and are brittle materials. Moreover, VB2, NbB2, and ZrB2 also meet the mechanical stability standards. Research shows that the anisotropy of MB2 is: NbB2 > VB2 > ZrB2.The quasi-harmonic Debye model is used to study the thermodynamic properties of compound MB2 (M = V, Nb, Zr). We analyzed the change curve of heat capacity, volume, thermal expansion coefficient, and Debye temperature at 0–1600 K and 0–100GPa. According to the analysis of thermodynamic properties, MB2 also satisfies the thermal stability condition. Finally, this paper studies the absorption and reflection of light by MB2. It is found that absorption and reflection are relatively strong in the ultraviolet region. [ABSTRACT FROM AUTHOR]

Abstract Background This study was designed to mainly evaluate the activity and safety of olanzapine compared with 5-hydroxytryptamine3(5-HT3) receptor antagonists for prevention of chemotherapy-induced nausea and vomiting(CINV) in patients receiving highly or moderately emetogenic chemotherapy (HEC or MEC). The second goal was to evaluate the impact of olanzapine on quality of life (QoL) of cancer patients during the period of chemotherapy. Methods 229 patients receiving highly or moderately emetogenic chemotherapy were randomly assigned to the test group [olanzapine(O) 10 mg p.o. plus azasetron (A) 10 mg i.v. and dexamethasone (D) 10 mg i.v. on day 1; O 10 mg once a day on days 2-5] or the control group (A 10 mg i.v. and D 10 mg i.v. on day 1; D 10 mg i.v. once a day on days 2-5). All the patients filled the observation table of CINV once a day on days 1-5, patients were instructed to fill the EORTC QLQ-C30 QoL observation table on day 0 and day 6. The primary endpoint was the complete response (CR) (without nausea and vomiting, no rescue therapy) for the acute period (24 h postchemotherapy), delayed period (days 2-5 poschemotherapy), the whole period (days 1-5 postchemotherapy). The second endpoint was QoL during chemotherapy administration, drug safety and toxicity. Results 229 patients were evaluable for efficacy. Compared with control group, complete response for acute nausea and vomiting in test group had no difference (p > 0.05), complete response for delayed nausea and vomiting in patients with highly emetogenic chemotherapy respectively improved 39.21% (69.64% versus 30.43%, p < 0.05), 22.05% (78.57% versus 56.52%, p < 0.05), complete response for delayed nausea and vomiting in patients with moderately emetogenic chemotherapy respectively improved 25.01% (83.07% versus 58.06%, p < 0.05), 13.43% (89.23% versus 75.80%, p < 0.05), complete response for the whole period of nausea and vomiting in patients with highly emetogenic chemotherapy respectively improved 41.38% (69.64% versus 28.26%, p < 0.05), 22.05% (78.57% versus 56.52%, p < 0.05), complete response for the whole period of nausea and vomiting in patients with moderately emetogenic chemotherapy respectively improved 26.62% (83.07% versus 56.45%, p < 0.05), 13.43% (89.23% versus 75.80%, p < 0.05). 214 of 299 patients were evaluable for QoL. Comparing test group with control group in QoL evolution, significant differences were seen in global health status, emotional functioning, social functioning, fatigue, nausea and vomiting, insomnia and appetite loss evolution in favour of the test group (p < 0.01). Both treatments were well tolerated. Conclusion Olanzapine can improve the complete response of delayed nausea and vomiting in patients receiving the highly or moderately emetogenic chemotherapy comparing with the standard therapy of antiemesis, as well as improve the QoL of the cancer patients during chemotherapy administration. Olanzapine is a safe and efficient drug for prevention of CINV.