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A new simple strategy based on TiO2@reduced graphene oxide (rGO) composites for QDSSCs is demonstrated in this study. We prepare TiO2@rGO-2 photoanodes in which graphene was obtained through hydrothermal and high-temperature reduction. This task is conducted to make TiO2@rGO composite be uniformly mixed together. The SILAR method is applied to the QDs adsorption of TiO2@rGO composites. Compared with that of TiO2@rGO-1 photoanodes, the complete reduction properties of TiO2@rGO-2 photoanodes result in a remarkable increase in the photovoltaic characteristics of solar cells. The relevant performance characteristics of QDSSCs are observed, and the current–voltage curve results show CdS/TiO2@rGO-2 and Mn2+–CdS/TiO2@rGO-2 photoelectric conversion efficiencies of 1.51% and 2.54%, respectively. These measured values are almost 10% higher than those of cells with TiO2@rGO-1 as photoanode, in fact. Electrochemical impedance testing results show that the effective secondary reduction of graphene leads to this meaningful enhancement.

Introduction The efficacy of dopamine versus epinephrine for pediatric or neonatal septic shock remains controversial. We conduct a meta-analysis to explore the influence of dopamine versus epinephrine on shock reversal for pediatric or neonatal septic shock. Methods We have searched PubMed, EMbase, Web of science, EBSCO, and Cochrane library databases through July 2019 for randomized controlled trials (RCTs) assessing the efficacy and safety of dopamine versus epinephrine for pediatric or neonatal septic shock. Results Three RCTs are included in the meta-analysis. Overall for pediatric or neonatal septic shock, dopamine and epinephrine reveal comparable shock reversal within 1 h (risk ratios (RR) = 0.61; 95% CI = 0.16 to 2.31; P = 0.47), mortality (RR = 1.16; 95% CI = 0.87 to 1.55; P = 0.30), heart rate (standard mean differences (SMD) = 0.03; 95% CI = -0.28 to 0.34; P = 0.85), systolic blood pressure (SMD = -0.18; 95% CI = -0.69 to 0.33; P = 0.49), mean arterial pressure (SMD = -0.15; 95% CI = -1.64 to 1.34; P = 0.84) and adverse events (RR = 1.00; 95% CI = 0.94 to 1.07; P = 0.91). Conclusions Dopamine and epinephrine show the comparable efficacy for the treatment of pediatric or neonatal septic shock.

In this paper, we developed a simple and convenient method for incorporating graphene with anatase-rutile TiO2 composite and applied it as photoanode to improve the photovoltaic performance of CdS QDSSCs. Our research indicated in a CdS QDSSC system, the photoelectric conversion efficiency (PCE) of anatase-rutile TiO2 (TGr0) composite photoanode was 86% higher than that rutile TiO2 NRs. We also found that the PCE increased first and then decreased with the change of graphene content after the graphene was introduced into the anatase-rutile TiO2 photoanode. When the ratio of optimized graphene/anatase TiO2 particles composite that spin-coated on rutile TiO2 NRs photoanode was 5%, we attained a maximum PCE of 2.20%, which was 178% and 50% higher than that pure TiO2 NRs (0.79%) and TGr0 (1.47%), respectively.

Phototropism and photomorphogenesis play important roles in plant growth. In this work, a series of novel Ba2LaNbO6 (BLN):Mn4+,Yb3+ phosphors for plant-cultivation light-emitting diodes (LEDs) were successfully synthesized through a high-temperature solid-state reaction. The emission peak of Mn4+ centered at 677 nm matched the red light emission required for phototropism well, while that of Yb3+ centered at 998 nm matched the far-red light emission required for photomorphogenesis. SEM images of the BLN:Mn4+,Yb3+ phosphors developed in this study showed that the samples were composed of micron-sized particles that can be coated onto LED chips. The photoluminescence excitation spectra of the phosphors showed broad bands from 250 nm to 550 nm, matching those of LED chips well. The activation energy of Mn4+ in the BLN:Mn4+ phosphor was calculated to be approximately 0.462 eV, thus confirming the good thermal stability of the material. The CCT, CRI, and luminous efficiency of a developed LED were 4021 K, 76.8, and 38 Im/W, respectively. Analysis of fluorescence lifetimes proved the occurrence of energy transfer between Mn4+ and Yb3+, and the intensity ratio of far-red and near-infrared emissions could be controlled by adjusting the doping ratio of Mn4+ and Yb3+ to meet the requirements of different plants. Taken together, the results showed that BLN:Mn4+,Yb3+ is a phosphor that can potentially be applied to plant-cultivation LEDs.

A novel Mn4+-doped Ca2GdNbO6 (CGN) phosphor was prepared by high-temperature solid-state reaction. The crystal structure was investigated by X-ray diffraction patterns and unit cell structure. Mn4+ replaced the location of Nb5+ in the CGN lattice, and the value of energy gap (Egap) decreased from 2.16 eV to 1.13 eV, indicating that Mn4+ ions play a great influence on the absorption of CGN hosts. The broad excitation band from 250 nm to 550 nm matches well with commercial near-UV light emitting diodes, and the emission peak centered at 680 nm is due to 2E→4A2g transition in Mn4+ ions. The CIE chromaticity coordinates (0.698, 0.303) of CGN:Mn4+ phosphor was close to standard red color coordinates (0.666, 0.333). These investigations demonstrate CGN:Mn4+ phosphor as an efficient red phosphor for potential applications.

A novel ferrierite type zeolite named as IEZ-Al-PLS-3(S4R) with pore sizes of 14 × 12-ring (R) was post synthesized by simply interlayer silylation of lamellar precursor Al-PLS-3 taking 1,3,5,7-tetramethylcyclosilone (TMCS) as silane. Its catalytic properties were tested by isomerization/disproportionation of m-xylene, alkylation/acylation of anisole with benzyl alcohol/acetic anhydride. The catalytic performance of IEZ-Al-PLS-3(S4R) was compared with Al-PLS-3 (10 × 8-R) and IEZ-Al-PLS-3(1Si) (12 × 10-R) which were prepared by calcination or silylation using dimethoxydimethylsilane (DEDMS) as silane of as made Al-PLS-3 respectively. Since these materials have the same laminates composition, the differences of catalytic performance can be considered as the result of different pore sizes. We also prepared conventional 10-R zeolite ZSM-5 and 12-R zeolite Beta for control experiments. IEZ-Al-PLS-3(S4R) showed even higher catalytic activities than Beta as a result of its enlarged 14-R pore size.

Graphene is known as an electro-chemical material and widely used in electro-chemical devices, especially in solar cell. Decreasing the thickness of the layer is a critical way to improve the electrochemical property of solar cells as far as possible. Among the various oxidation approaches, presented herein is a facile approach, which is easier, less cost and more effective, environmental benign with the greener processing and without any requirement for post purification, towards the synthesis of graphene oxide (GO) with different oxidation degrees by potassium ferrate (K2FeO4). A modified method using less amount of oxidizing agent is reported herein. It is the pretreatment of the synthesis of graphite, which maintains the thermal cycle of the system. This novel reports to compound GO with controlled oxidation degrees can not only increase the quantity of oxygen-containing functional groups on GO surface, increase space between graphene oxide layer and facilitate the dispersion of graphene in aqueous solution. Thus, the modified method shows prospect for large-scale production of graphene oxide and its novel application, in addition to its derivative and market potential for solar cells.

We show that in a four-level atomic system with electromagnetically induced transparency, a coherent pump field can induce light amplification without or with population inversion. As the pump field intensity increases, the atomic system evolves from normal dispersion and amplification without population inversion into anomalous dispersion and amplification with population inversion. We report an experiment on light amplification in cold rubidium atoms and present experimental measurements that agree with theoretical calculations based on the four-level model system.