RESUMEN
Organic dyes in natural waters jeopardize human health. Whether semiconductor materials can effectively degrade dyes has become a challenge for scientific research. Based on this, this study rationally prepared different nanocomposites to remove organic dyes effectively. Pure SnO2 quantum dots, ZnO nanosheets, and SnO2/ZnO (ZS) binary nanocomposites are prepared using the hydrothermal method. Subsequently, SnO2/ZnO@GO (ZSG) ternary composites containing different amounts of GO, i.e., ZSG-5, ZSG-15, and ZSG-25, are synthesized by an ultrasonic water bath method, in which ZS was coupled with GO to form Z-type heterojunctions. The ZSG-15 ternary composites exhibited excellent photocatalytic activity for the degradation of rhodamine B by simulating sunlight. The test results show that the degradation rate of ZSG-15 is about 7.6 times higher than ZnO. The increase in photocatalytic activity is attributed to the synergistic effect of SnO2 and GO to improve the separation efficiency of photogenerated carriers in ZnO. Notably, the large specific surface area of GO increases the reactive sites. Compared with binary nanocomposites, ZSG-15 broadens the response range to light while further accelerating the electron transport rate and improving the photoelectric stability.
RESUMEN
Two new tin(II) phosphates, SnII SnIV (PO4 )2 and SrSn(PO4 )PO2 (OH)2 , were synthesized by the high-temperature solution method and hydrothermal method, respectively. Theoretical study indicates that by introducing tin(II) with stereochemical activity lone pairs (SCALP) in metal phosphates, the birefringence was enhanced, 0.048@1064â nm for SnII SnIV (PO4 )2 and 0.080@1064â nm for SrSn(PO4 )PO2 (OH)2 .
RESUMEN
Sn3B10O17Cl2 was successfully obtained for the first time under the sealed environment and crystallized in the space group Pbcn belonging to the orthorhombic system, which is featured by the fundamental building blocks [B5O11] that are linked to construct a three-dimensional framework with Cl and Sn atoms located inside and at the edge of the channel to balance the charge. Moreover, the optical performance measurement shows that Sn3B10O17Cl2 owns a cutoff edge of about 280 nm. Theoretical study indicates its large optical anisotropy with the birefringence 0.125@546 nm; meanwhile, the structure-performance relationships were analyzed by the first-principle calculation.
RESUMEN
The development of high-power solid-state lasers is in urgent need of new infrared nonlinear optical (IR NLO) materials with a wide band gap and a high laser-induced damage threshold. A new infrared nonlinear optical material Na2Ga2SiS6 has been synthesized for the first time, crystallizing in the Fdd2 (no. 43) noncentrosymmetric space group. Its three-dimensional tunnel framework consists of two typical NLO active motifs [GaS4] and [SiS4], with Na+ cations located inside the tunnels. Na2Ga2SiS6 exhibits comprehensive optical properties, namely, a wide transmission range, a high laser-induced damage threshold (10 × AgGaS2), a type-I phase-matching second-harmonic generation response (0.2 × AgGaS2), and especially a wide band gap (3.93 eV), which is the largest in the A2MIII2MIVQ6 (A = alkali metals; MIII = IIIA elements; MIV = IVA elements; Q = S and Se) family. Therefore, Na2Ga2SiS6 does not produce two-photon absorption under a 1064 nm laser pump and could be used in high-energy laser systems, which makes Na2Ga2SiS6 a promising candidate for high-energy IR NLO applications.
RESUMEN
Geographic patterns in body size are often associated with latitude, elevation, or environmental and climatic variables. This study investigated patterns of body size and cell size of the green anole lizard, Anolis carolinensis, and potential associations with geography or climatic variables. Lizards were sampled from 19 populations across the native range, and body size, red blood cell size and size and number of muscle cells were measured. Climatic data from local weather stations and latitude and longitude were entered into model selection with Akaike's information criterion to explain patterns in cell and body sizes. Climatic variables did not drive any major patterns in cell size or body size; rather, latitude and longitude were the best predictors of cell and body size. In general, smaller body and cell sizes in Florida anoles drove geographic patterns in A. carolinensis. Small size in Florida may be attributable to the geological history of the peninsular state or the unique ecological factors in this area, including a recently introduced congener. In contrast to previous studies, we found that A. carolinensis does not follow Bergmann's rule when the influence of Florida is excluded. Rather, the opposite pattern of larger lizards in southern populations is evident in the absence of Florida populations, and mirrors the general pattern in squamates. Muscle cell size was negatively related to latitude and red blood cell size showed no latitudinal trend outside of Florida. Different patterns in the sizes of the 2 cell types confirm the importance of examining multiple cell types when studying geographic variation in cell size.