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Bi nanoparticles were used to fabricate Bi/Bi2O3 heterojunction by an in situ sintering method in a muffle furnace. The experimental results show that the surface plasmon resonance (SPR) effect and oxygen vacancy (OV) defects of Bi/Bi2O3 hybrids can enhance the visible-light absorption and carrier separation efficiency, and thus improve the photocatalytic activity of Bi/Bi2O3 composites for tetracycline (TC) degradation under visible-light illumination. Moreover, by means of increasing the calcination time of Bi nanoparticles, the photocatalytic degradation efficiency of the as-prepared hybrids shows a tendency of first increasing and then decreasing. When the calcination time was 15 min, a maximum value of 81.7% was reached within 60 min. This is higher than that of 16% of the pristine Bi nanoparticles. In addition, h+ plays a major role during the degradation reaction of TC. This study can provide promising guide for the rational design and development of Bi-based photocatalysts and degradation of antibiotics under solar light illumination. [ABSTRACT FROM AUTHOR]

A cauliflower-like In2.77S4 has been synthesized using polyvinylpyrrolidone (PVP) as a surfactant, and the In2.77S4/BiVO4 composite photocatalysts were further prepared via a hydrothermal method. The photocatalytic activity of the samples was evaluated using tetracycline (TC) dilute solution. The photocatalytic degradation mechanism of the as-prepared composites was also discussed. Moreover, the state density and electron transfer of as-constructed composites were investigated through density-functional theory (DFT). Analysis results show that the as-hybridized products have higher photocatalytic activity than pure samples. With increasing the amount of BiVO4, the photocatalytic activity of the as-constructed In2.77S4/BiVO4 composites is firstly increased and then decreased. The best photocatalytic degradation efficiency of the as-prepared composite for TC is 89.9% in 90 min, which is higher than 61% of In2.77S4 and 51% of BiVO4, respectively. The reason of photocatalytic property enhancement is that there are chemical bonds between the interface of In2.77S4 and BiVO4, and it is confirmed that h+ plays a leading role during the photocatalytic degradation process. This work can provide a reference for the treatment of antibiotics pollution in water under solar light. [ABSTRACT FROM AUTHOR]

The yolk–shell Bi@void@SnO2 photocatalyst was synthesized via a step-by-step process. The composition, morphology, optical and photoelectrochemical properties as well as the surface chemical composition and states of the samples were characterized by X-ray diffraction, transmission electron microscopy, UV–Vis diffuse reflectance spectra, electrochemical impedance spectra and X-ray photoelectron spectrometer, respectively. The tetracycline has been used to evaluate the photocatalytic activities of the as-synthesized samples. Compared with the degradation efficiency of 16.33% for pure Bi and almost nothing for SnO2 under visible light irradiation, the as-developed Bi@void@SnO2 photocatalyst possesses 81.81% of degradation efficiency. Meanwhile, the light absorption of the as-developed yolk–shell composites is broadened from ultraviolet to visible light comparing to pure SnO2 due to the surface plasmon resonance effect of Bi spheres. Moreover, the superoxide radicals, especially in holes, play leading roles during the photocatalytic degradation process. In addition, the decomposition mechanism of the as-fabricated composites for tetracycline is analyzed in detail. [ABSTRACT FROM AUTHOR]

The AgI/2D-La2Ti2O7 hybrids were obtained via a facile method at room temperature. Rhodamine B, as an organic dye, was used to determine the photocatalytic activity of the samples. The photocatalytic degradation mechanism was also analyzed. Experimental results display that AgI can broaden the light absorption of La2Ti2O7 under the visible light irradiation. The photocatalytic degradation efficiency of the as-synthesized hybrids appears the tendency of first increasing and then decreasing with increasing the usage of La2Ti2O7. When the usage of La2Ti2O7 is 10%, within 60 min, the as-synthesized hybrids possess the maximum of 93.1%. This is higher than 2.1% of La2Ti2O7 and 80.9% of AgI. Moreover, the improved photocatalytic activity can be attributed to AgI particles conjugating with 2D-La2Ti2O7 nanosheets via chemical-bonds, which can enhance the separation and transformation of the photo-generated holes and electrons. In addition, the dominating role is superoxide radicals during the photocatalytic process. [ABSTRACT FROM AUTHOR]

The Ag2CrO4/SnO2 n-n type heterojunction has been fabricated by coupling Ag2CrO4 particles with SnO2 nanorods via an in situ synthetic method. The photocatalytic degradation mechanism of the as-prepared heterojunction has also been discussed. Characterization results revealed that the as-fabricated Ag2CrO4/SnO2 composites could reinforce the photo-degradation competencies for rhodamine B dilute solution compared to pure Ag2CrO4 and SnO2 samples. As the increase in the molar ratios of Ag2CrO4-SnO2, the photocatalytic degradation efficiency appeared to the tendency of first increasing and then decreasing. When it was 4:10, in 90 min, the as-obtained samples possessed the vintage photocatalytic degradation efficiency of 95.8% among of pure SnO2, Ag2CrO4 and the as-prepared composites with various molar ratios, respectively. Furthermore, the Ag2CrO4 and SnO2 were connected via chemical bonds to form the homogenous heterojunction. It could boost the separation and transfer of the photogenerated holes and electrons. In addition, the holes, hydroxyl and superoxide radicals played a major role during the photodegradation process. [ABSTRACT FROM AUTHOR]

The direct Z-scheme Ag2WO4/WS2 photocatalysts had been fabricated by using a deposition method. Experimental results indicated that WS2 nanosheets could improve the photocatalytic activity, light absorption and recyclability of Ag2WO4 under the visible light irradiation. The degradation efficiency of the as-obtained Ag2WO4/WS2 hybrids for rhodamine B displayed first increasing and then decreasing with increasing the usage of WS2 nanosheets. When the usage of WS2 was 15 wt%, in 120 min, it reached the maximum of 97.8%, which was higher than 17.8% of pure Ag2WO4. Moreover, after three cycles of the degradation, the as-prepared hybrids still possessed 94.4% of the degradation efficiency, which increased by 1211.1% compared with pure Ag2WO4. Moreover, superoxide and hydroxyl radicals played major role during the process of photocatalytic degradation. The enhanced photocatalytic activity could be ascribed to the formation of direct Z-scheme photocatalytic system between Ag2WO4 and WS2. [ABSTRACT FROM AUTHOR]

The novel AgCl/Ag2SO3 hybrids as an efficient photocatalyst had been fabricated by an in situ synthetic method. The correlations between the structure and the photocatalytic properties of the as‐fabricated hybrids were analyzed. Experimental results exhibited that with increasing the amount of Ag2SO3, the degradation rate of the as‐obtained samples was firstly increased and then decreased under the visible light irradiation. When the mass ratio of AgCl to Ag2SO3 was 1:2, in 30 min, it displayed the highest degradation rate of 99.2% for rhodamine‐B, which was obviously higher than 46.1, 60.5, and 14.6% of pure AgCl, Ag2SO3, and TiO2 (P25), respectively. Similar results could be found in degradation of methyl orange. It had the maximum of 97.4% in 90 min, which was higher than 55.2, 48.7, and 12.7% of pure AgCl, Ag2SO3, and P25, respectively. Moreover, the as‐prepared hybrids possessed the enhanced separation and transfer of photo‐generated electron–hole pairs compared to the pure samples. In addition, the holes and superoxide radicals played the dominant role and the hydroxyl radicals played the secondary role during the process of photocatalytic degradation. [ABSTRACT FROM AUTHOR]

Hexagonal boron nitride was adopted as a heterogeneous nucleation agent to fabricate polyamide 6 based nanocomposite films via a solution casting method. Isothermal crystallization behaviors of the as-prepared films were measured by using differential scanning calorimetry. Results showed that both the crystallization temperature and fillers loading greatly affected the crystallization process of the asprepared samples. The crystallization nucleation and growth mechanism did not change during the initial stage of crystallization. The halftime of crystallization gradually increased with increasing crystallization temperature. Moreover, it decreased first and then increased with increasing the fillers loading at low crystallization temperature, while it decreased gradually at high crystallization temperature. Furthermore, the crystallization activation energy of the as-prepared samples gradually decreased with increasing fillers loading. [ABSTRACT FROM AUTHOR]

1. Although the importance of elevated circulating plasma catecholamines on cardiac structural and functional remodelling of hypertension is well documented, it is unclear whether the catecholamine–b-adrenoreceptor (bAR)–cAMP system can predict different cardiovascular events. 2. A total of 601 identified hypertensive patients with baseline and follow-up plasma levels of noradrenaline (NA) and adrenaline (Adr), lymphocyte bAR density (Bmax) and intralymphocyte cAMP levels in peripheral blood (last examination 60 ± 26 months apart) were followed up for an additional 24 ± 12 months. 3. After the last follow up, a composite end-point of cardiovascular death, non-fatal myocardial infarction (MI) and stroke occurred in 139 patients (23.1%). In Cox analyses, adjusting for other standard factors as well as treatment effect, NA (hazard ratio 1.22; 95% confidence interval (CI) 1.17–1.28; P = 0.0008), Adr (hazard ratio 1.53; 95% CI 1.18–2.00; P = 0.002), bAR (hazard ratio 1.12; 95% CI 1.06–1.17; P = 0.007) and cAMP (hazard ratio 1.15; 95% CI 1.09–1.21; P = 0.005) separately predicted cardiovascular mortality. Noradrenaline, Adr, bAR and intralymphocyte cAMP separately predicted fatal/non-fatal MI; NA and Adr predicted fatal/non-fatal stroke, whereas Bmax and intralymphocyte cAMP levels were not a significant predictor of fatal/non-fatal stroke. When stratifying the study population by NA or Adr (median 4 nmol/L), Bmax (median 600 fmol/107 cells) and cAMP (median 5.0 pmol/mg protein) above and below the median values in both parameters categories, patients above the median had composite cardiovascular end-point (all P < 0.001) and high cardiovascular death (all P < 0.01, log-rank test). 4. These results suggest that plasma NA and Adr are significant predictors of cardiovascular mortality, MI and stroke. The Bmax and intralymphocyte cAMP levels are significant predictors of cardiovascular mortality and MI, but not stroke. [ABSTRACT FROM AUTHOR]

The Zn2+ doped In2.77S4 (Zn–In2.77S4) photocatalyst has been synthesized via a one-step hydrothermal method. The tetracycline was adopted to measure the photocatalytic performance of the as-fabricated Zn–In2.77S4 composites. The probable photocatalytic degradation mechanism of the as-prepared composites was also discussed. Experimental results reveal that doping Zn2+ into In2.77S4 can broaden the light absorption range and improve the recycle ability as well as the separation efficiency of photo-generated electron–hole pairs of pure In2.77S4. Moreover, as the doping amount of Zn2+ increased the photocatalytic efficiency of the as-obtained Zn–In2.77S4 composites appears the tendency of firstly increasing and then decreasing. When the molar ratio of Zn2+ to In3+ is 0.04:1 (4%), in 15 min, the photocatalytic efficiency of the as-developed Zn–In2.77S4 photocatalyst reaches to the maximum of 90.0%. It is higher than 31.8% of pure In2.77S4. Furthermore, superoxide radicals and holes play major roles in the process of photodegradation tetracycline. This research can supply a promising guide to solve antibiotics pollution in water under sunlight. [ABSTRACT FROM AUTHOR]

The In2.77S4/SrCO3 heterojunction photocatalyst had been prepared by one-step hydrothermal method. X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectrometry, UV-Vis diffuse reflectance spectroscopy and electrochemical impedance spectroscopy were used to analyze the structure, morphology, chemical compositions, optical properties and charge carrier behaviors of the as-prepared In2.77S4/SrCO3 hybrids, respectively. Experimental results revealed the SrCO3 could obviously improve the recyclability and photocatalytic activities of In2.77S4 nanosheets for both methyl orange and tetracycline oxidation under visible light. The photocatalytic degradation efficiency of the as-obtained In2.77S4/SrCO3 hybrids was first increased and then decreased with increasing the molar ratio of Sr(NO3)2 to In(NO3)3·4.5H2O. When it was 0.4:1, that of the as-prepared hybrids with the band gap of 1.63 eV reached the maximum of 96.0% in 30 min for methyl orange and 82.7% in 20 min for tetracycline. These were higher than 88.0% and 40.0% of In2.77S4 nanosheets as well as 0.8 and 1.8% of SrCO3 particles, respectively. After three cycles, its photocatalytic efficiency still possessed 92.7% for methyl orange and 80.3% for tetracycline, which were much higher than 35.3% and 11.3% of In2.77S4 nanosheets. Moreover, the possible photocatalytic degradation mechanism of the In2.77S4/SrCO3 hybrids was also proposed. [ABSTRACT FROM AUTHOR]

The In2.77S4 microspheres had been firstly fabricated by using polyethylene glycol (PEG) as the morphological modifier and then used to hybridize with In(OH)3 nanocubes by a simply depositional method. The structure, optical properties, morphology, chemical compositions, and charge carrier behaviors of the as-prepared In2.77S4/In(OH)3 composites were characterized, respectively. The methyl orange, tetracycline, rhodamine B, and Cr(VI) dilute solution were selected to evaluate their photocatalytic activities. Experimental results showed that In(OH)3 nanocubes could improve the photocatalytic activity and recyclability of the In2.77S4 microspheres under the visible light irradiation. With the usage of In(OH)3 increased, the photocatalytic efficiency of the hybrids was firstly increased and then decreased. When the mass ratios of In2.77S4 to In(OH)3 were 6:2, it reached the maximum of 100% in 15 min for methyl orange, obviously higher than 67.4% of In2.77S4 and 1.1% of In(OH)3. Meanwhile, it could also oxidize 85.6% of tetracycline in 20 min, 97.8% of rhodamine B in 7.5 min, and reduce 92.9% of Cr(VI) in 30 min under the visible light irradiation. Moreover, it could still degrade 91.7% of methyl orange solution after 3 cycles, which was much higher than 40.7% of In2.77S4 microspheres. In addition, the possible mechanism of enhancing photocatalytic properties was proposed. [ABSTRACT FROM AUTHOR]

To assess the relations of vascular ground flora to soil organic carbon (SOC) contents, we carried out plant census and soil sampling in 3 forest stands, i.e. 1-year and 3-year eucalyptus planted forests and a secondary broadleaved forest in western Guangdong, China. Variability in species composition and diversity in the ground flora was tested using multi-response permutation procedures (MRPP), and potential species indicators were detected by indicator species analysis (ISA). Dominant species in the ground flora differentiated natural secondary forest from eucalyptus planted forests, and the SOC content of the 0~25 cm soil layer varied significantly across the 3 forest stands. Significant differences in SOC content were found among the 5 groupings of the ground flora, which was defined by two-way indicator species analysis (TWINSPAN). MRPP indicated that species composition and diversity of the ground flora varied significantly in response to a gradient of SOC content. ISA revealed that 19 species, including Smilax glabra (IV > 50), were indicative of soil environments with high SOC content (> 30 g·kg-1), and only 1 species, i.e. Inula cappa, were indicative of low SOC content (< 20 g·kg-1). This study suggested that indicator species of different SOC regimes can be detected using a simple community analysis technique, and such indicator plants can be used for soil nutrient and soil carbon pool dynamics monitoring and assessment. [ABSTRACT FROM AUTHOR]

Objective To investigate the stratification risk of catecholamines-β-adrenoceptor (β-AR)-cAMP pathway for cardiogenic death events in patients with congestive heart failure (CHF). Methods A total of 83 identified CFIF patients with a baseline and follow-up plasma levels of norepinephrine (NE) and epinephrine (E), lymphocytes β-AR density (Bmax), and intralymphocyte cAMP content in peripheral blood were followed up. Major cardiogenic death events were registered. Results The period between the initial entry and the last follow-up measurement were 51±16 months, the total duration of clinical follow-up after the last measurement were 14±8 months. During follow-up, 39 patients died of cardiogenic (sudden death 17 patients, worsening heart failure 22 patients). Persistence of high NE, E, and cAMP from baseline to follow-up were confirmed as risk predicting factors of cardiovascular events. Persistence NE above 4.0 nmol/L, E above 3.5 nmol/L, and the intralymphocyte cAMP content above 3.5 pmd∙ mg-1∙pro-1 from baseline to follow-up were significant adverse prognostic predictors. The major cardiogenic death events rates per 100 patients-years were 1.33 and 4.82 in patients with NE below and above 4.0 nmol/L (HR: 2.91; 95% CI: 1.08-7.33; P = 0.015); were 1.42 and 4.36 in the patients with E levels below and above 3.5 nmol/L (HR: 2.64; 95% CI: 1.02-6.41; P= 0.019); were 1.81 and 4.67 in the patients with the intralymphocyte cAMP content below and above 3.5 pmd∙mg-1∙pro-1 (HR: 2.79; 95% CI: 1.04-6.83; P = 0.017), but difference was not significant between the β-AR density below and above median. Conclusions Persistent increase in circulating catecholamines and intralymphocyte cAMP content may increase the long-term mortality in CHF patients. [ABSTRACT FROM AUTHOR]