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This study was conducted to investigate the efficiency and characteristics of de-nitrification using bamboo as solid phase carbon source in a batch and continuous flow mode. Compared to no solid phase carbon source system, the higher nitrate-N removal efficiency and the less nitrite-N accumulation was observed in a de-nitrification system by using bamboo as solid phase carbon source. The results showed that nitrate-N volumetric load averaged between 2.09 mg/L.h when filamentous bamboo as single carbon source, and mean nitrite-N accumulations was only 0.23 mg as 1 g nitrate-N was removed. Moreover, temperature was an important influencing factor for nitrate-N volumetric load and nitrite accumulation. In addition, refractory organic compounds and nitrate-N can simultaneous remove.

The purpose of this study is to investigate the efficiency and characteristics for treatment of polluted landscape water using filamentous bamboo as bio-carrier. Results demonstrated that the COD removal rate could be increased more 13% because glucose was added into the raw. And the COD removal was mainly decided for the biofilm on the filamentous bamboo, which is 2.53 times higher than activitcd sludge in a batch hybrid unit. Additionally, Rich biological phases was obversed during the test.

A novel MnO 2 /graphene (G)/nickel foam (NF) composite as supercapacitor electrode was fabricated by a facile electrochemical deposition approach for the first time. The approach includes electrophoretic deposition of G on NF (EPD-G/NF) and electrodeposition of MnO 2 on EPD-G/NF (MnO 2 /EPD-G/NF). Compared with other methods for preparing MnO 2 /G composite, our green strategy avoids using harsh chemicals (e.g. hydrazine) or high temperature treatment for reducing graphene oxide. Owing to unique structure, specific capacitance ( C s ) of the MnO 2 /EPD-G/NF electrode is as high as 476 F g − 1 at high current density of 1 A g − 1 in 0.5 M Na 2 SO 4 solution, which is the highest C s for MnO 2 /G composites to date, and the C s is higher than that of MnO 2 /NF electrode. Furthermore, it also exhibits high rate capacity, such as 216 F g − 1 of C s at 10 A g − 1 . On the other hand, our strategy provides a versatile method for fabrication of other G-based composites with metal oxide/hydroxide or conducting polymer as supercapacitor electrode.

The article reviewed the advanced methods of ecological floating bed including usage of non-biodegradable bio-carrier, choosen of excellent plants, ion-beam irradiation, immobilized bacteria and aeration. Based on the review, the authors present the idea using biodegrable materials as bio-carrier, which not only could enhance the biomass in the ecological floating bed, but also could overcome the insufficience in carbon source for biological denitrification.

The effect of the electrodeposition temperature on the electrochemical performance of Ni(OH)2 electrode was investigated in this report. Ni(OH)2 was electrodeposited directly on nickel foam at different temperatures. The crystalline structure, morphology and specific surface area of the prepared Ni(OH)2 were characterized by X-ray powder diffraction (XRD), field emission scanning electronic microscopy (FESEM) and Brunauer–Emmett–Teller (BET). Electrochemical techniques such as cyclic voltammetry (CV), chronopotentiometry, and electrochemical impedance spectra (EIS) were carried out to systematically study the electrochemical performance of various Ni(OH)2 electrodes in 1 M KOH electrolyte. The results demonstrated that the electrodeposition temperature had obviously affected the properties of the Ni(OH)2. A pure α-Ni(OH)2 phase could be observed at low temperature. When the temperature increased to 65 °C, the β-Ni(OH)2 phase together with α-Ni(OH)2 phase were present. Moreover, the sample synthesized at 65 °C possessed a porous honeycomb-like microstructure and the corresponding specific capacitance was up to 3357 F g−1 at a charge–discharge current density of 4 A g−1, which suggested its potential application as an electrode material for supercapacitors.

For the problem of wetting collapsible loess foundation in loess area, and common methods used in dealing with collapsible loess foundation are insufficiency, new treatment technologies, including loess solidified by polymer and comprehensive method of dynamic compaction and chemical solidification, were proposed. Experimental studies on loess solidified by a series of SH were carried out. The results show that the loess solidified by SH has advantages of high strength, good water-resistance, and frost resisting, low-cost. Consequently, SH is feasible to deal with loess foundation. Because it fits in with the development trend for new combined technology in reinforcement of rock and soil, dynamic compaction and chemical solidification has some applying prospects. In order to establish this new method, things correlated with the study should be done.

Two parallel biofilm reactors were developed and applied for treating the simulated wastewater. The experimental results showed that compared with a without electric-shocking biofilm, and a mean removal rate of COD increased by 18.82% by shocking of direct current. Which suggested that the electro-shocking can significantly increase the removal rate of COD.

Novel dual molecular- and ion-recognition responsive poly(N-isopropylacrylamide-co-benzo-12-crown-4-acrylamide) (PNB12 C4 ) linear copolymers with benzo-12-crown-4 (B12C4) as both guest and host units are prepared. The copolymers exhibit highly selective sensitivities toward γ-cyclodextrin (γ-CD) and Na(+) . The presence of γ-CD induces the lower critical solution temperature (LCST) of PNB12 C4 copolymer to shift to a higher value due to the formation of 1:1 γ-CD/B12C4 host-guest inclusion complexes, while Na(+) causes a negative shift in LCST due to the formation of 2:1 "sandwich" B12C4/Na(+) host-guest complexes. Regardless of the complexation order, when γ-CD and Na(+) coexist with PNB12 C4 , competitive complexation actions of B12C4 as both guest and host units toward γ-CD and Na(+) finally form equilibrium 2:2:1 γ-CD/B12C4/Na(+) composite complexes, and the final LCST values of PNB12 C4 copolymer reach almost the same level. The results provide valuable guidance for designing and applying PNB12 C4 -based smart materials in various applications.

Three dimensional manganese dioxide/Pt/nickel foam (shortened to MnPtNF) hybrid electrodes were prepared by double-pulse polarization and potentiostatic deposition technologies for supercapacitor applications. The decoration of Pt nanoparticles onto nickel foam varies the nucleation mechanism of the manganese dioxide species, inducing the formation of manganese dioxide nanosheets. Additionally, controlling the size of the Pt nanoparticles leads to modulated nanosheet architecture and electrochemical properties of the manganese dioxide electrode, as revealed by XRD, Raman spectra, SEM, TEM, cyclic voltammetry, galvanostatic charge-discharge and electrochemical impedance spectroscopy. The nanosheet architecture of the MnPtNF electrode favors the transportation of electrons and ions, which results in the enhanced electrochemical properties. Importantly, the optimized MnPtNF electrode obtains a maximum specific capacitance of 1222 F g(-1) at 5 A g(-1) (89% of the theoretical specific capacitance of MnO2) and 600 F g(-1) at 100 A g(-1). Moreover, the presence of Pt nanoparticles in the MnO2 electrode effectively improves its cycling stability, which is confirmed by the increase of the specific capacitance retention from 14.7% to 90% after 600 cycles.

A three dimensional (3D) nanostructured nickel oxide (NiO) electrode was fabricated by an electrodeposition method employing nickel foam (NF) as a scaffold and used for glucose detection. Taking advantage of the synergetic effect of NF and NiO, the 3D NiO/NF electrode shows excellent performance in glucose detection.

3D NiχCo1−χ oxides with different morphologies for high-capacity supercapacitors were controllably synthesized via an electrodeposition method combined with a simple post annealing process. The synthesis involves the co-electrodeposition of the bimetallic (Ni, Co) hydroxide precursor on a nickel foam scaffold and subsequent thermal transformation to NiχCo1−χ oxides. The crystalline structure, morphology and electrochemical performance of the 3D NiχCo1−χ oxides can be readily manipulated by simply varying the Co/Ni molar ratio in the electrodeposition electrolyte. With the increase of the Co/Ni molar ratio, the characteristic peak intensities and the signal sites were gradually changed from a NiO crystal dominant structure to NiCo2O4 and finally to a Co3O4 dominant structure. Moreover, the morphology also can be controlled by adjusting the Co/Ni molar ratio in the electrodeposition electrolyte. In addition, the Ni0.61Co0.39 oxide electrode shows a large specific capacitance of 1523.0 F g−1 at 2 A g−1 and 95.30% of that can be retained, even at a high current density of 30 A g−1. The superior rate capability should be attributed to the unique 3D network-like architecture, which can enlarge the liquid–solid interfacial area, facilitate the electron and ion transport, and further increase the utilization of the active material. To demonstrate its practical application, an asymmetric supercapacitor based on the Ni0.61Co0.39 oxide electrode as a positive electrode and activated carbon as a negative electrode was fabricated. Owing to the outstanding capacitive behavior of the Ni0.61Co0.39 oxide electrode, the asymmetric device delivers a prominent energy density of 36.46 W h kg−1 at a power density of 142 W kg−1, and which holds great promise for potential applications in energy storage.

The negative electrical effects of Pd and Rh metals at the Si-SiO 2 interface and the heat treatment behavior of these effects are studied experimentally. In addition, the results of electron spectroscopy analysis of the impurity-doped interfaces are also presented.

After having investigated the transition metals palladium(Pa) and rhodium(Rh), we have found in our experiments that the rare-earth metals Gd and La are another kind of metal impurities producing negative electric effects at the Si-SiO 2 interface. In this paper, we present the results of our investigation on the influence of heat-treatment on these effects and the results of AES and ESCA studies of the impurities-doped interfaces. These results will be briefly discussed in terms of the relevant action mechanisms of the negative electric effects.