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A novel two-stage biological/flocculation process was developed for treating the pulping effluent from the alkaline peroxide mechanical pulping (APMP) process. In the first biological stage, the aerobic fermentation by using Aspergillus niger can decrease the chemical oxygen demand (COD) by about 60% while producing about 7 g/l of solid biomass. In the second stage (post-coagulation/flocculation), the residual COD, turbidity and color, can be further decreased by using alum and polyacrylamide (PAM). The overall removal efficiencies of COD, color and turbidity from the APMP pulping effluent by the above two-stage biological-coagulation/flocculation process were 93%, 92% and 99%, respectively, under the conditions studied., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Background: As common pathogens in the human respiratory tract, fungal-spore-related health risks have been challenging to evaluate properly. This paper presents numerical simulations of particle deposition of Aspergillus niger spores in human nasal cavities. Methods: 30 healthy adults (including 60 nasal chambers) who lived in northwest China were recruited to conduct a nasal cavity numerical simulation using computational fluid dynamics–discrete phase model (CFD-DPM). The deposition rate in each anatomic area and its influencing variables, such as body position and respiratory flow rate, were analyzed. Results: (1) Under a resting condition, only about 5.57% ± 1.51% Aspergillus niger spores were deposited in the nasal cavity, while most of them escaped from the nasopharynx, and 0.31% ± 0.20% spores entered the maxillary sinus; (2) under an exercising condition, spores deposited in the nasal cavity were about 2.09 times as many as that in the resting state; (3) in a lying position, the A. niger spores deposited evenly on the lateral wall of the nasal cavity and the sinus when compared with a standing position. However, the deposition rate in each anatomic area did not change significantly. [ABSTRACT FROM AUTHOR]

Six corroded glazed pottery figurines, which excavated from the Qibi Ming Tomb of the Tang Dynasty in Xianyang, were selected to study the corrosion mechanism. Optical microscopy (OM), scanning electron microscopy equipped with energy dispersive X-ray spectrometry (SEM–EDS), Energy X-ray fluorescence spectrometry (EDX), and micro-Raman spectroscopy were applied to analyze the pristine composition of the glaze layer and pottery substrate, the composition and microstructure of corrosion products. The results indicate that lead-glazed pottery figurines are low-temperature PbO-CaO-SiO2 glaze, with Pb as the main flux, and Cu, Fe as the main colorant. The corrosion products include PbCO3, CaCO3, PbCO3·PbCl2, PbCl2, PbO2, and Si-rich layer. There are Aspergillus niger and Aspergillus sclerotiorum on the surface of glazed pottery. These microorganisms produce organic acids and mold spots on the surface of the pottery figurines, which in turn cause corrosion pits to form on the surface of the figurines. Chemical corrosion reactions mainly include dissolution–precipitation, combination reaction, and oxidation reaction. This article describes the corrosion process of lead-glazed pottery figurines and establishes corresponding corrosion models. This study provides new insights into the corrosion mechanism of lead-glazed pottery, which is of great significance for studying pottery corrosion. [ABSTRACT FROM AUTHOR]

Rot disease is a serious disease in pomegranate (Punica granatum L.) plantations in China. This disease usually weakens tree vigor, and seriously reduces the ornamental value, fruit yield, and quality. A better understanding of the pathogen that causes a disease is important for its control. Thus, the aims of this study were to isolate and identify the pathogen causing rot disease and to explore substances for its biological control. In this study, the morphology of the hyphae and spores of the pathogens was observed, and the pathogens were identified by morphological characteristics and the internal transcribed spacer (ITS) regions of their rDNA. Furthermore, the activity of an aqueous garlic extract as antifungal treatment for the identified pathogens was assessed. The results showed that the pathogens causing soft rot and dry rot in ‘Xinjiang Big Seed’ pomegranate were most probably Aspergillus niger and Botryosphaeria dothidea, respectively. In addition, the pathogenicity of A. niger was stronger than that of B. dothidea. The aqueous garlic extract had a strong antifungal effect on both pathogens by inhibiting mycelium growth in vitro, and the minimum inhibitory concentrations against A. niger and B. dothidea were 7.5 mg/mL and 10 mg/mL, respectively. [ABSTRACT FROM AUTHOR]

Heavy metals were bioleached from municipal solid waste incineration fly ash by Aspergillus niger (AS 3.879) using one-step and two-step bioleaching. The pH variation, organic acids, and metals concentrations, as well as the metals extraction yield of these two processes were compared. The maximum metals extraction yield was obtained in one-step bioleaching of 20 g/L fly ash, where 98.7% of Mn, 87.6% of Cd, 69.7% of Cu, 68.5% of Zn, 42.1% of Cr, 31.7% of Fe, and 36.5% of Pb were extracted; meanwhile, the pH decreased to 3.03 and the fungus secreted 36.6 mmol/L gluconic acid after 336 h. The results indicated that one-step bioleaching was preferable for the treatment of fly ash at low concentrations (10–20 g/L). Two-step bioleaching was appropriate to detoxify the fly ash at high concentrations (40–50 g/L) because A. niger grew and generated 33.9 mmol/L gluconic acid even at 50 g/L fly ash in two-step bioleaching compared to the fungal growth only observed at 10–40 g/L fly ash in one-step bioleaching. The gluconic acid was determined as the major leaching agent both in one-step and two-step bioleaching. In addition, the TCLP tests results of the bioleached fly ash showed that the leaching toxicities of the treated fly ash were far lower than the regulated levels of China. [ABSTRACT FROM AUTHOR]

The article presents abstracts of several studies on environmental geochemistry. Some of the abstracts presented include "Biogeochemical Cycling of Nutrients in Karstic Catchments, Southwestern China: Linkages to Changes of Eco-Environments," by Congqiang Liu and "Emerging Organic Contamination in China," by Guibin Jiang and colleagues.