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English language copy of the questionnaire. (DOCX 29 kb)

Copper-based nanoparticles were synthesized using the glycine–nitrate process (GNP) by using copper nitrate trihydrate [Cu(NO3)2‧3H2O] as the main starting material and glycine [C2H5NO2] as the complexing and incendiary agent. The as-prepared powders were characterized through X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET) analysis, X-ray photoelectron spectroscopy, and scanning electron microscopy. Using Cu(NO3)2.3H2O as the oxidizer (N) and glycine as fuel (G), we obtained CuO, mixed-valence copper oxides (CuO + Cu2O, G/N = 0.3–0.5), and metallic Cu (G/N = 0.7). The XRD and BET results indicated that increasing the glycine concentration (G/N = 0.7) and reducing particle surface area increased the yield of metallic Cu. The effects of varying reaction parameters such as catalyst activity, catalyst dose, and H2O2 concentration on nonylphenol-9-polyethoxylate (NP9EO) degradation were assessed. With a copper‐based catalyst in a heterogeneous system, the NP9EO and total organic carbon removal efficiencies were 83.1% and 70.6%, respectively, under optimum operating conditions (pH, 6.0; catalyst dose, 0.3 g/L; H2O2 concentration, 0.05 mM). The results suggested that removal efficiency increased with an increase in H2O2 concentration but decreased when the H2O2 concentration exceeded 0.0.5 mM. Furthermore, the trend of photocatalytic activity was as follows: G/N = 0.5 > G/N = 0.7 > G/N = 0.3. The G/N = 0.5 catalysts showed the highest photocatalytic activity and resulted in 94.6% NP9EO degradation in 600 min.

Community characteristics of Stipa roborowskyi steppe in Xizang YANG Yao, GUO Ke, ZHAO Li-Qing, ZHAO Hai-Wei, QIAO Xian-Guo, LIU Hui-Ming, and LIU ChangCheng State Key Laboratory of Vegetation and Environmental Change, Institute of Botany, Chinese Academy of Sciences, Beijing 100093, China; University of Chinese Academy of Sciences, Beijing 100049, China; College of Life Sciences, Inner Mongolia University, Hohhot 010021, China; and Satellite Environment Center, Ministry of Environmental Protection, Beijing 100094, China

Antimony toxicity occurs either due to occupational exposure or during therapy. There is a growing need for biological monitoring of antimony to provide exposure information to help prevent hazardous exposure. This study presents supercritical carbon dioxide (SC-CO2) extraction as an inherently safe and clean sample treatment method for analyzing trace antimony in spiked human urine. Extraction was performed in the presence of a fluorinated β-diketone chelating agent, thenoyltrifluoroacetone, by unmodified SC-CO2. Quantitative extractions were conducted at 60 °C and 17.2 MPa with 15 min static plus 10 min dynamic extractions. The extracts were subsequently analyzed by graphite furnace atomic absorption spectroscopy with spiking Pd(NO3)2–Mg(NO3)2 matrix modifier. The proposed procedure was successfully applied to determine the concentrations of antimony in spiked urine samples with satisfactory recoveries of 95.6%–102.9% (n = 6) and relative standard deviations