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BACKROUND Few studies have been carried out to connect nutrients recovery from wastewater and heavy metals immobilization in contaminated soil. To achieve the goal, ammonia nitrogen ( AN) and phosphorus (P) were recovered from rare-earth wastewater by using the formation of struvite, which was used as the amendment with plant ash for copper, lead and chromium immobilization. RESULTS AN removal efficiency and residual P reached 95.32 ± 0.73% and 6.14 ± 1.72 mg L−1 under optimal conditions: pH=9.0, n(Mg): n(N): n(P) = 1.2:1:1.1, which were obtained using response surface methodology ( RSM). The minimum available concentrations of Cu, Pb and Cr ( CPC) separately reduced to 320.82 mg kg−1, 190.77 mg kg−1 and 121.46 mg kg−1 with increasing immobilization time at the mass ratio of phosphate precipitate ( PP)/plant ash ( PA) of 1:3. Humic acid ( HA) and fulvic acid ( FA) were beneficial to immobilize Cu, both of which showed no effect or even a negative effect on Pb and Cr immobilization. CONCLUSION Building up a suitable 'bridge' to connect and achieve recovery of nutrients and reuse of struvite. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

Activated carbon (AC) was prepared from surplus sludge using chemical activation method with the assistance of ZnCl. The influences of process parameters on the AC's specific surface area and adsorption capacity for Pb were examined to optimize these parameters. The optimal conditions for the preparation of AC were determined to be activation temperature of 500 °C, activation time of 1 h, impregnation ratio of 1:1 (solid-to-liquid volume) with the 30% ZnCl solution (mass fraction), giving the BET surface area of 393.85 m/g and yield of 30.14% with 33.45% ash. Also, the pyrolysis temperature was found to be the most important parameter in chemical activation. FTIR spectra provided the evidence of some surface structures such as C=C and C-O-C. In the adsorption studies, a rise in solution pH led to a significant increase in adsorption capacity when the pH value varied from 3.0 to 7.0, and the optimal pH for removal of Pb was 7.0. It was observed that the pseudo-second-order equation provided better correlation for the adsorption rate than the pseudo-first-order and the Langmuir model fitted better than the Freundlich model for adsorption isotherm. The adsorption capacity of AC to Pb was 11.75 mg/L at solution pH 7.0, the equilibrium time 480 min and 25 °C. Moreover, the adsorption process is endothermic according to the value of enthalpy change. [ABSTRACT FROM AUTHOR]

To improve the utilization and investment efficiency of large-scale apparatus and equipment, and to offer a beter service to university V education, research and the local economy construction, universities should pursue to construct a sharing platform of large-scale apparatus and equipment. The status of large-scale apparatus and equipment management in universities was analyzed. Based on working practice, main problems, such as low utilization rate, imperfect management system, low level of operationin, in the opening-up and sharing management of large-scale apparatus and equipment in universities were discussed and analyzed, because investment mechanism of large-scale instrument and equipment was not perfect, management was closed of, rigorous scientific proof was insufficient before purchase, management mode was limited, the management system opening to the outside world was lack, operation management level was low and management and technical team was not enough. Suggestions and measures which could promote the opening-up and sharing management and improve the utilization efficiency of large-scale apparatus and equipment in universities were discussed from drawing up policy laws and regulations, reforming management system and operational mechanism. Thesec suggestion couold make the profitable utilization plan and establishing working model. [ABSTRACT FROM AUTHOR]

The adsorption of two phenols, namely, phenol and salicylic acid (SA) onto a water-compatible hypercrosslinked polymeric resin (NJ-8) were studied in terms of pseudo-second-order and first order mechanisms for chemical sorption as well as an intraparticle diffusion mechanism process. Kinetic analysis showed that the intraparticle diffusion process was the essential rate-controlling step. The activation energies of sorption have also been evaluated with the pseudo-second-order and intraparticle diffusion constants, respectively. Adsorption equilibrium data were well fitted by the Langmuir, Freundlich and Redlich-Peterson isotherms. Adsorption was exothermic and basically of a type of transition between physical and chemical character. The sorption capacity was higher for SA due to its more hydrophobic. Phenol has a higher adsorption enthalpy since it could form stronger hydrogen bonding on NJ-8. [ABSTRACT FROM AUTHOR]

Nano-hydroxyapatite (n-HA) was used to make a new hydrogel biocomposite with poly(vinyl alcohol) (PVA) by a unique technique. Fourier transform infrared absorption spectra (IR), transmission electron microscopy (TEM), X-ray diffraction (XRD), thermogravimetric analysis (TG) and burning test were used to test the physical and chemical characteristics of the composite. Chemical binding between inorganic n-HA and poly(vinyl alcohol) was investigated and discussed. The results showed that the composite had good thermal stability and homogeneity. The n-HA crystals were uniformly distributed in the polymer matrix. The improved n-HA/PVA hydrogel could be used as an artificial articular cartilage, showing a promoting prospect. [ABSTRACT FROM AUTHOR]

Our previous studies have demonstrated that the urotensin (UII) and its receptor are up-regulated in the skeletal muscle of mice with type II diabetes mellitus (T2DM), but the significance of UII in skeletal muscle insulin resistance remains unknown. The purpose of this study was to investigate the effect of UII on NADPH oxidase and glucose transport signaling pathways in the skeletal muscle of mice with T2DM and in C2C12 mouse myotube cells. KK/upj-AY/J mice (KK) mice were divided into the following groups: KK group, with saline treatment for 2 weeks; KK+ urantide group, with daily 30 µg/kg body weight injections over the same time period of urantide, a potent urotensin II antagonist peptide; Non-diabetic C57BL/6J mice were used as normal controls. After urantide treatment, mice were subjected to an intraperitoneal glucose tolerance test, in addition to measurements of the levels of ROS, NADPH oxidase and the phosphorylated AKT, PKC and ERK. C2C12 cells were incubated with serum-free DMEM for 24 hours before conducting the experiments, and then administrated with 100 nM UII for 2 hours or 24 hours. Urantide treatment improved glucose tolerance, decreased the translocation of the NADPH subunits p40-phox and p47-phox, and increased levels of the phosphorylated PKC, AKT and ERK. In contrast, UII treatment increased ROS production and p47-phox and p67-phox translocation, and decreased the phosphorylated AKT, ERK1/2 and p38MAPK; Apocynin abrogated this effect. In conclusion, UII increased ROS production by NADPH oxidase, leading to the inhibition of signaling pathways involving glucose transport, such as AKT/PKC/ERK. Our data imply a role for UII at the molecular level in glucose homeostasis, and possibly in skeletal muscle insulin resistance in T2DM. [ABSTRACT FROM AUTHOR]