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A novel and highly efficient Ag3VO4/C3N4/reduced TiO2 microsphere composite was obtained through a hydrothermal and depositional process. The microstructure, individual components with different proportions, and optical properties of the ternary nanocomposites were intensively studied. The prepared ternary composites exhibited superior photocatalytic performance of degradation of methylene blue compared with single component and S1 (C3N4/reduced TiO2) binary composites, demonstrating that the introduction of Ag3VO4 into g-C3N4/r-TiO2 can effectively improve the photocatalytic activity. Recycling experiments confirmed that the nanocomposites exhibited superior cycle performance. The enhanced capability could be attributed to a synergetic effect including the formation of heterojunction, large surface area, improved light absorption, matched energy band structure, and the improved separation efficiency of photogenerated charges coming from dual Z-scheme structure. Particularly, the introduction of Ag3VO4 makes the dual Z-scheme charge transfer pathway completed with improved separation efficiency and stronger redox ability of photogenerated electrons and holes. The work provides a promising method to develop a new dual Z-scheme photocatalytic system to remove environmental pollutant.
Given the global water challenges, solar-driven steam generation has become a renewed topic recently as an energy-efficient way for clean water production. Here, a hybrid plasmonic structure consisting of a top layer of TiN nanoparticles (NPs) and a bottom layer of mesoporous anodized alumina membrane (AAM) was rationally designed and fabricated. The top TiN NPs with broadband light absorption acted as a plasmonic heating layer, which converted the absorbed light to heat efficiently for interfacial water heating. The AAM acted as the mechanical support layer, guaranteeing the heat isolation and continuous water replenishment. With optimized thickness of the TiN top layer, a solar steam generation efficiency of 87.7% was achieved in this study. This efficiency is comparable or even higher than prior studies. The current work proves the capability of the TiN NPs as an alternative photothermal material.
This paper presents new water-soluble bio-polyelectrolyte-based nanoparticles, formed from lanthanide-induced polysaccharide aggregates (LIPAs). These new nano-aggregates are formed by coordinating a photoluminescent lanthanide–ligand complex to a single polyelectrolyte [i.e. polyanionic hyaluronic acid (HA)] or to two oppositely charged polyelectrolytes [i.e. HA and polycationic chitosan (CHI)]. We demonstrate that photoluminescent Eu3+–ligand complexes, which are dispersed homogeneously in aqueous solution by the association with water-soluble HA. The polysaccharide supermolecular assembly can be tuned to obtain nanoparticles of different sizes and surface charges. The preparation of stable and water-soluble lanthanide complexes via Eu3+–LIPAs opens opportunities for use of luminescent lanthanides in aqueous environments, for biosensing and bioimaging applications.
Auto-alignment is a basic technique for high-power laser systems. Special techniques have been developed for laser systems because of their differing structures. This paper describes a new sensor for auto-alignment in a laser system, which can also serve as a reference in certain applications. The authors prove that all of the beam transfer information (position and pointing) can theoretically be monitored and recorded by the sensor. Furthermore, auto-alignment with a single lens sensor is demonstrated on a simple beam line, and the results indicate that effective auto-alignment is achieved.
Suboptimal vitamin B2 status is encountered globally. Riboflavin deficiency depresses growth and results in a fatty liver. The underlying mechanisms remain to be established and an overview of molecular alterations is lacking. We investigated hepatic proteome changes induced by riboflavin deficiency to explain its effects on growth and hepatic lipid metabolism. In all, 360 1-d-old Pekin ducks were divided into three groups of 120 birds each, with twelve replicates and ten birds per replicate. For 21 d, the ducks were fed ad libitum a control diet (CAL), a riboflavin-deficient diet (RD) or were pair-fed with the control diet to the mean daily intake of the RD group (CPF). When comparing RD with CAL and CPF, growth depression, liver enlargement, liver lipid accumulation and enhanced liver SFA (C6 : 0, C12 : 0, C16 : 0, C18 : 0) were observed. In RD, thirty-two proteins were enhanced and thirty-one diminished (>1·5-fold) compared with CAL and CPF. Selected proteins were confirmed by Western blotting. The diminished proteins are mainly involved in fatty acid β-oxidation and the mitochondrial electron transport chain (ETC), whereas the enhanced proteins are mainly involved in TAG and cholesterol biosynthesis. RD causes liver lipid accumulation and growth depression probably by impairing fatty acid β-oxidation and ETC. These findings contribute to our understanding of the mechanisms of liver lipid metabolic disorders due to RD.
Nine possible native point defects in MgCaSi have been studied by employing density functional theory based ab initio calculations. The complex chemical potential limits are first determined using a two-dimension (∆μMg, ∆μCa) diagram, then the defect formation energies as a function of the atomic chemical potential are gained. The energetic results show that under Mg-rich conditions, the most favorable defect is MgCa rather than MgSi, while CaMg is predominant compared to CaSi under Ca-rich conditions. The bonding energy is first introduced to uncover the intrinsic feature of defect formation energy. The local geometric distortion around CaMg, MgSi, and CaSi antisite defects gradually increases due to the smaller atomic radii from Ca to Mg and Si, showing the important role of the geometrical mismatch. The density of states indicates that the higher stability of CaMg and MgCa originates from the smaller deviation of the Fermi level from the pseudo-gap.
The Ga-doped ZnO (GZO) were deposited by magnetron reactive sputtering on glass substrates at room temperature with different deposited times to obtain various thickness. The root-mean-square (RMS) roughness obtained from the atomic force microscopy (AFM) images is observed to shift linearly with the deposited time, the fractal geometry and multi-resolution signal decomposition (MRSD) based on wavelet transform were applied on the surface profiles and the results does not synchronously changes as the thickness, which is related to the profile’s frequency. The calculated compressive in-plane stress of highly c-axis oriented GZO films also shows an irregular variation as the increase of film thickness, what’s more, the in-plane stress and fractal dimension exhibit a polynomial relationship and the two parameters can be used for describing the surface morphology.
Based on 15 diffusion couples located in face centered cubic single-phase region of ternary Ni–Al–Mo system, high-throughput determination of composition-dependent interdiffusivity matrices at 1273, 1373, and 1473 K was performed by using the recently developed numerical inverse method. The determined main interdiffusivities over the investigated composition and temperature ranges are all positive, and
is generally larger than
generally increases with concentration of Al, while
increases with concentrations of both Al and Mo. In contrast, the cross interdiffusivities can be either positive or negative. Average relative errors of
were evaluated to be 2.4, 5.1, 16.1, and 1.7% using error propagation. Furthermore, our prediction of composition profiles and interdiffusion fluxes based on evaluated interdiffusivity matrices agrees quite well with measured data. Traditional Matano–Kirkaldy method was also applied to further verify the reliability of obtained interdiffusivities. Besides, three-dimensional planes of activation energies of main interdiffusivities were also evaluated using the Arrhenius equation.
A new planar microstrip-fed monopole ultra-wideband (UWB) antenna with dual notched bands has been presented. By employing a simple dual-mode resonator with two symmetrical outer high-impedance lines beside the microstrip feed line of the proposed UWB antenna, two controllable rejection bands with high-frequency selectivity are created. The parametric studies of the proposed structure are explored for the dual band-notched operating mechanism. Finally, the experimental results, including return losses, radiation patterns, and peak gains are shown, declaring that the proposed antenna has good impedance matching performance and radiation pattern properties.
Hydrophobic functionalized SBA-15 has been developed via postsynthesis modification with trimethylchlorosilane (TMCS) and used for volatile organic compounds (VOCs) removal. The adsorption and desorption performance of different SBA-15-TMCS under static and dynamic conditions were investigated. Experimental results indicated that all samples showed a highly ordered two dimensional hexagonal mesostructure, and the organic groups were chemically incorporated into the pore surface of SBA-15 substrate. Comparing with commercial silica gel and activated carbon, SBA-15-TMCS shows higher static adsorption capacities of n-hexane and 93# gasoline, good recyclability, lower water vapor adsorption capacity, higher dynamic adsorption capacity, and longer breakthrough time. The high adsorption efficiency and stability of SBA-15-TMCS are associated with their hydrophobic surface, uniform and large pore size, high surface area and pore volume. The designed SBA-15-TMCS with high VOC adsorption capacity and recyclability shows great potential for VOC removal.
Using trait activation theory as a framework, this study developed and tested a cross-level model of individual innovative behavior. Data from a sample of 334 employees within 75 work teams were used to examine the hypothesized model. Results showed that employee learning goal orientation was positively related to innovative behavior only when the team structure was more organic. Additionally, the relationship between employee learning goal orientation and innovative behavior would be strongest when both the team structure was more organic and team mean learning goal orientation was higher.
X-ray powder diffraction data, unit-cell parameters, and space group for calcium(II)–naproxen complex, C28H26CaO6·2H2O, are reported [a = 36.918(2) Å, b = 5.655(6) Å, c = 12.505(6) Å, β = 91.263(2)°, cell volume V = 2610.47 Å3, Z = 4, and space group C2]. All measured lines were indexed and are consistent with the C2 space group. No detectable impurities were observed.
The association of 24 h urinary Na and potassium excretion with the risk of the metabolic syndrome (MetS) has not been studied in China. The aim of the present study was to examine this association by analysing the data from 1906 study participants living in north China. To this end, 24 h urine samples were collected. Of the 1906 participants, 471 (24·7 %) had the MetS. The mean urinary Na and K excretion was 228·7 and 40·8 mmol/d, respectively. After multivariate adjustment, the odds of the MetS significantly increased across the increasing tertiles of urinary Na excretion (1·00, 1·40 and 1·54, respectively). For the components of the MetS, the odds of central obesity, elevated blood pressure and elevated TAG, but not the odds of low HDL-cholesterol and elevated fasting glucose, significantly increased with the successive tertiles of urinary Na excretion. Furthermore, for every 100 mmol/d increase in urinary Na excretion, the odds of the MetS, central obesity, elevated blood pressure and elevated TAG was significantly increased by 29, 63, 22 and 21 %, respectively. However, urinary K excretion was not significantly associated with the risk of the MetS. These findings suggest that high Na intake might be an important risk factor for the MetS in Chinese adults.
A seawater salinity sensor based on microring resonator with weak temperature dependence is proposed, which is coated by MgF2 film with positive thermo-optic coefficient. Temperature dependences of the sensor on fiber diameter, probing wavelength and coating thickness are theoretically investigated and ranges of microfiber diameters for weak temperature dependence are obtained. Under the temperature insensitive condition, sensitivity and detection limit of salinity sensing are studied. By optimizing the parameters of the sensing system, salinity sensitivity and detection limit can reach 0.03 nm/‰ and 0.13‰, respectively. The model presented here may be helpful for developing weak temperature dependence sensors for salinity sensing with high sensitivity, low detection limit and miniaturized sizes.
Due to the existence of spatial walk-off and/or group-velocity mismatch effects, pump-to-signal phase transfer becomes inevitable during parametric amplification. We experimentally demonstrate that in hybrid seeded optical parametric amplifiers (OPAs) that include two OPA stages seeded by the signal and idler waves, respectively, the phase of the output signal can be restored to its initial value, although there are spatial and temporal phase fluctuations on the pump source. This method significantly relaxes the requirement for high pump beam quality, which is always very stringent in parametric amplification systems. With the introduction of this scheme into birefringent phase-matching OPAs or chirped-pulse OPAs, it should be promising to achieve intense femtosecond laser pulses that are close to the diffraction limit in space and ultra-high contrast in time, simultaneously.
To assess correlations between cruciferous vegetable intake and urinary isothiocyanate (ITC) level, in addition to glutathione S-transferase (GST) genotypes and other individual factors.
The study included cohort participants whose urinary ITC levels had been previously ascertained. Urinary ITC was assessed using HPLC. Usual dietary intake of cruciferous vegetables was assessed using a validated FFQ and total dietary ITC intake was calculated. Recent cruciferous vegetable intake was determined. GST genotypes were assessed using duplex real-time quantitative PCR assays. Spearman correlations were calculated between the covariates and urinary ITC levels and linear regression analyses were used to calculate the mean urinary ITC excretion according to GST genotype.
Urban city in China.
The study included 3589 women and 1015 men from the Shanghai Women’s and Men’s Health Studies.
Median urinary ITC level was 1·61 nmol/mg creatinine. Self-reported usual cruciferous vegetable intake was weakly correlated with urinary ITC level (rs=0·1149; P<0·0001), while self-reported recent intake was more strongly correlated with urinary ITC (rs=0·2591; P<0·0001). Overall, the GST genotypes were not associated with urinary ITC level, but significant differences according to genotype were observed among current smokers and participants who provided an afternoon urine sample. Other factors, including previous gastrectomy or gastritis, were also related to urinary ITC level.
The study suggests that urinary secretion of ITC may provide additional information on cruciferous vegetable intake and that GST genotypes are related to urinary ITC level only in some subgroups.
Potassium dihydrogen phosphate (KDP) single crystals are the only nonlinear crystals currently used for electro-optic switches and frequency converters in inertial confinement fusion research, due to their large dimension and exclusive physical properties. Based on the traditional solution-growth process, large bulk KDP crystals, usually with sizes up to 600
so as to make a frequency doubler for the facility requirement loading highly flux of power laser, can be grown in standard Holden-type crystallizers, without spontaneous nucleation and visible defects, one to two orders of magnitude faster than by conventional methods. Pure water and KDP raw material with a few ion impurities such as Fe, Cr, and Al (less than 0.1 ppm) were used. The rapid-growth method includes extreme conditions such as temperature range from 60 to 35
C, overcooling up to 5
C, growth rates exceeding 10 mm/day, and crystal size up to 600 mm. The optical parameters of KDP crystals were determined. The optical properties of crystals determined indicate that they are of favorable quality for application in the facility.
This study aimed at examining three tilt angle-based positive responses and the time to positive response in a head-up tilt test for children with orthostatic intolerance, and the psychological fear experienced at the three angles during head-up tilt test. A total of 174 children, including 76 boys and 98 girls, aged from 4 to 18 years old (mean 11.3±2.8 years old), with unexplained syncope, were randomly divided into three groups, to undergo head-up tilt test at the angles of 60°, 70° and 80°, respectively. The diagnostic rates and times were analysed, and Wong–Baker face pain rating scale was used to access the children’s psychological fear. There were no significant differences in diagnostic rates of postural orthostatic tachycardia syndrome and vasovagal syncope at different tilt angles during the head-up tilt test (p>0.05). There was a significant difference, however, in the psychological fear at different tilt angles utilising the Kruskal–Wallis test (χ2=36.398, p<0.01). It was mildest at tilt angle 60° utilising the Kolmogorov–Smirnov test (p<0.01). A positive rank correlation was found between the psychological fear and the degree of tilt angle (rs=0.445, p<0.01). Positive response appearance time was 15.1±14.0 minutes at 60° for vasovagal syncope children. There was no significant difference in the time to positive response, at different tilt angles during the head-up tilt test for vasovagal syncope or for postural orthostatic tachycardia syndrome. Hence, it is suggested that a tilt angle of 60° and head-up tilt test time of 45 minutes should be suitable for children with vasovagal syncope.
Mexican sunflower is a native species of North and Central America that was introduced into China early last century, but it has widely naturalized and become a harmful invasive plant in tropical and subtropical regions in South China. Inter-simple sequence repeat (ISSR) markers were employed to assess genetic diversity and variation in Mexican sunflower populations from China and neighboring regions. The karyotypes of populations were also studied. Our research showed high levels of genetic diversity in all populations. The lowest genetic diversity estimates were represented in two populations in Laos, suggesting prevention of new introductions into Laos is critical. Partitioning of genetic variance revealed that genetic variation was mostly found within populations, and unweighted pair group method with arithmetic means (UPGMA) analysis showed that the introductions into China and Laos were independent. There were no obvious correlations between genetic relationships and geographic distance of populations in China, consistent with the human associated dispersal history of Mexican sunflower. Previous cytological data and our chromosome count (2n = 34) and karyotype analysis showed chromosome stability among populations. The high levels of genetic diversity within invasive Mexican sunflower populations could be challenging for its management in China, and further expansion and potential negative effects on ecological systems of this plant should be monitored.
The purpose of the present study was to evaluate the impact of a lifestyle intervention programme, combined with a daily low-glycaemic index meal replacement, on body-weight and glycaemic control in subjects with impaired glucose regulation (IGR). Subjects with IGR were randomly assigned to an intervention group (n 46) and a control group (n 42). Both groups received health counselling at baseline. The intervention group also received a daily meal replacement and intensive lifestyle intervention to promote healthy eating habits during the first 3 months of the study, and follow-up visits performed monthly until the end of the 1-year study. Outcome measurements included changes in plasma glucose, glycated Hb (HbA1c), plasma lipids, body weight, blood pressure and body composition (such as body fat mass and visceral fat area). The results showed that body-weight loss after 1 year was significant in the intervention group compared with the control group ( − 1·8 (sem 0·35) v.− 0·6 (sem 0·40) 2·5 kg, P< 0·05). The 2 h plasma glucose concentration decreased 1·24 mmol/l in the intervention group and increased 0·85 mmol/l in the control group (P< 0·05) compared with their baseline, respectively. A 5 kg body-weight loss at 1 year was associated with a decrease of 1·49 mmol/l in 2 h plasma glucose (P< 0·01). The incidence of normal glucose regulation (NGR) in the two groups was significantly different (P= 0·001). In conclusion, the combination of regular contact, lifestyle advice and meal replacement is beneficial in promoting IGR to NGR.