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Abstract: In recent years, wetland restoration measures have created extensive concerns globally. The theory and practice of restoring wetland vegetation diversity in wetlands through soil seed banks is discussed in this paper. A comparative study on soil seed bank and species composition in Yeyahu Wetland, Beijing, was conducted in 2007. Species and quantities of seeds from 12 sample sites were counted and measured by the seed-germinating method. After germination, 27 species belonging to 16 families and 23 genera were recorded, with an average of 11.75 species per sample site, and total average density of 24831.0individuals/m2. There were significant differences between the soil seed bank and vegetation in spring, summer and autumn, with similarity coefficients of 0.2620±0.0868, 0.2580±0.0778 and 0.1953±0.0452, respectively. Also in 2008, by using the seed bank technique, vegetation diversity was restored in a degraded wetland near Maying River of Yeyahu Wetland through the processes of spot selection, topographic surveying, water level monitoring, and vegetation management. The results showed that in the restored regions, both species and diversity coefficients of vegetation observably increased: 73.68% of the hydrophytic species we discovered were transplanted from provenance regions; germination of seeds in the soil lasted until late September; and many species completed their life history and produced new seeds to renew the seed bank. In addition, the results suggested that seed bank technique not only increased richness and multiplicity of vegetation, but also provided food chains with animal diversity in wetlands. [Copyright &y& Elsevier]

Abstract: In this paper, we reported the successful synthesis of hollow hemispherical Mn11(HPO3)8(OH)6 superstructures on a large scale via a facile mixed-solvothermal route without assistance of any surfactant, employing MnAc2·4H2O and NaH2PO2·H2O as the reactants, the mixture of N,N-dimethylformamide (DMF) and water as the solvent. The reaction was carried out at 160°C for 12h. HPO3 2− ions were provided via the dismutation reaction of H2PO2 − ions. The as-obtained product was characterized by X-ray powder diffraction (XRD), energy dispersive spectrometry (EDS) and field emission scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Some factors influencing the morphology of the hollow hemispherical Mn11(HPO3)8(OH)6 superstructures, such as the reaction temperature, time, the amount of NaH2PO2, and the volume ratio of DMF/water, were systematically investigated. A possible growth mechanism was proposed based on experimental results. [Copyright &y& Elsevier]

Abstract: The perovskite single-crystalline LaMnO3 nanocubes have been fabricated through a facile salt-assisted solution combustion process, using ethylene glycol as a fuel and corresponding nitrates as oxidants. The effects of the fuel-to-oxidant molar ratio and the fraction of added NaCl on the phase and microstructure of the products were investigated by X-ray diffraction, transmission electron microscopy and selected area electron diffraction. The possible mechanism about the effect of molten salt on morphological evolution of the as-prepared LaMnO3 particles in salt-assisted solution combustion synthesis was also discussed. [Copyright &y& Elsevier]

Abstract: Urchin-like CuO microspheres have been successfully synthesized via a simple water–ethyleneglycol (water–EG) mixed-solvothermal route at 100°C for 12h, employing cupric chloride (CuCl2) and potassium hydroxide (KOH) as starting reactants in the absence of any surfactant or template. The as-obtained product was characterized by means of powder X-ray diffraction (XRD), transmission electron microscopy (TEM), and field-emission scanning electron microscopy (FESEM). It was found that the volume ratio of water and EG played an important role in the formation of urchin-like CuO microspheres. The UV–vis absorption and the photocatalytic degradation for organic dyes of the final product were also studied. [Copyright &y& Elsevier]

Abstract: The saturation magnetostriction of α″-Fe16N2 phase was evaluated by measuring the magnetostriction curve of Fe84.8N7.8B7.4 ribbon with α″-Fe16N2 nanocrystallites embedded in an amorphous matrix. The magnetostriction measurement was carried out at room temperature by means of the three terminal capacitance method. The prepared sample exhibits a saturation magnetostriction of 2.52×10−6. The saturation magnetostriction of α″-Fe16N2 phase is evaluated to be −19.1×10−6 according to a simple rule of mixtures. [Copyright &y& Elsevier]

External inputs and internal cycling are two pathways of nutrients to the aquatic macrophytes in the wetland ecosystem. Internal sources of nutrients include plant die-off and the decomposition of organic matter. In this study, we used a stable nitrogen isotope ( 15 N) enrichment experiment to track the timing and magnitude of cattail ( Typha angustifolia ) use of coontail ( Ceratophyllum demersum ) – derived nitrogen (CDN) in a freshwater wetland. Dry coontail powder enriched in 15 N (δ 15 N = 1259 ± 15‰) was buried in the soil close to the roots of cattail plants in field mesocosms at the Yeyahu National Preserve, Beijing, China, from July 22 to September 30, 2014. Different parts (roots, rhizomes, stems, leaves and leaf apexes) of the cattail plants were collected at day 0, 14, 28, 42, 49, 56, 63 and 70 for stable isotope analysis. Results reveal uptake of the nitrogenous nutrient from coontail detritus by cattail four weeks after being exposed to CDN. The maximum uptake rate for excess 15 N in roots, leaves, stems, rhizomes and leaf apexes were 1.55 ± 0.84, 0.69 ± 0.11, 0.33 ± 0.08, 0.14 ± 0.11, 0.06 ± 0.02 mg 15 N m −2 . The root system is the largest pool of nitrogen in cattails, which serves as the source of nitrogen for other plant parts. The uptake rate per unit biomass was highest in the leaf apexes. [ABSTRACT FROM AUTHOR]

• Wetland Degradation Index (WDI) was constructed on a pixel-by-pixel basis. • WDI incorporates lake shrinkage index (LSI), vegetation/soil degradation index. • LSI considers long-term continuous variations of water extent with Landsat images. • First assessment on lake wetland degradation in Bashang Plateau, China. Continuous monitoring of wetland dynamics and regional-scale assessment of wetland degradation are important to understand wetland ecosystem processes and to formulate restoration measures. The lake wetlands in Bashang Plateau play vital roles in providing essential resources and maintaining biodiversity in North China, while they were not fully investigated in previous studies. In addition, previous studies on wetland degradation assessment mostly relied on wetland area change every five or ten years. Continuous dynamics of wetlands was rarely considered. In this study, we developed a new wetland degradation index (WDI) to assess lake wetland degradation in Bashang Plateau based on time series Landsat imagery from 1985 to 2020 on Google Earth Engine platform. WDI integrates three indicators, namely lake shrinkage index (LSI), vegetation degradation index (VDI) and soil degradation index (SDI), which represents hydrodynamics of wetland inundation, vegetation, and soil conditions of wetlands, respectively. Different from previous research that utilized remotely sensed image to extract wetland every five or ten years, the LSI considers time-series continuous dynamics of lake water inundations and the transitions between water and non-water on a pixel-by-pixel basis. Our results showed that small lake wetlands with area less than 8 ha are dominant in Bashang Plateau. Both the number and the area of lake wetlands showed large interannual variations. The number (area) of lake wetlands reached 1715 (31,419 ha) in 1995–1996 and were only 493 (7,717 ha) in 2009–2010. The total area of the lake wetlands in 2019–2020 was only around 1/3 of that in 1995–1996. The LSI, VDI, SDI, as well as WDI demonstrate large spatial variations among the lake wetlands and within the lake wetlands. Wetlands in the western and central subregions experienced more severe degradation than those in the eastern subregion, and the edge of the wetlands normally showed more severe degradation. The resulted degradation grades are consistent with our field investigations. Among the 11 counties in Bashang Plateau, Zhangbei (ZB) county in the western subregion has the largest area with severe and very severe degradation grades. Degradation of lake wetlands was mainly associated with groundwater level declination which was induced by anthropogenic activities and economic development. The proposed WDI in this study can be widely applicable for regional-scale wetland degradation assessment using remote sensing techniques and thus further help decision making in lake wetland conservation and restoration. [ABSTRACT FROM AUTHOR]

In this paper we reported a NH3·H2O-assisted solvothermal route for successful synthesis of cadmium hydroxyl chlorides (Cd x (OH) y Cl z ) microstructures with different phases and shapes, employing 1D CdQCl (Q=quinoline) complex microwires as the precursor. Experiments contained two processes: firstly, CdQCl complex microwires with 500–600nm in diameter and several hundreds of micrometers in length were prepared by the complexation between CdCl2·2.5H2O and quinoline at room temperature; then, CdQCl microwires were solvothermally treated at 150°C for 10h in the presences of different amounts of NH3·H2O to produce Cd x (OH) y Cl z microstructures with various phases and shapes. The as-obtained precursor and Cd x (OH) y Cl z microstructures were characterized by scanning electron microscopy, transmission electron microscopy, Infrared spectrometry and X-ray powder diffraction. Experiments showed that hexagonal Cd(OH)Cl was obtained from water–methanol system, while rhombohedral Cd4(OH)5Cl3 from methanol system. Also, it was found that the shapes of Cd x (OH) y Cl z could be tuned by the amounts of NH3·H2O. Furthermore, the UV diffuse reflection and photoluminescence spectra of the precursor and Cd x (OH) y Cl z were also investigated. [ABSTRACT FROM AUTHOR]

Abstract: Nickel phosphide nanocrystals with various phases have been successfully synthesized via a simple solvothermal route at 180°C for 16h, employing nickel chloride and white phosphorus (WP) as starting reactants in the presence of sodium dodecylbenzene sulfonate (SDBS). X-ray powder diffraction (XRD) research showed that the pure Ni12P5 phase with a high yield could be obtained in an ethanol solution, and the pure Ni2P form was prepared in a mixed system with the volume ratio of water/ethanol of 10:10. Namely, the presence of water molecules induced the phase conversion of nickel phosphides. Furthermore, in order to investigate the correlation between properties and phases, as a case, the photocatalytic degradation abilities of two nickel phosphide phases for organic dyes were compared. [Copyright &y& Elsevier]

Abstract: An integrated wetland system (IWS) including constructed wetlands (CWs) and modified natural wetlands (NWs) for wastewater treatment to replenish water to wetlands located at the Beijing Wetland School (BWS) in Beijing, China, is presented in this paper. The synergistic effects of CWs and NWs on treated water quality are investigated. The IWS is proved to be an effective wastewater treatment technique and a better alternative to alleviate the water shortage for conservation of wetlands based on the monitoring data obtained from October 2007 to 2008. The results show that CWs and NWs play different roles in removing contaminants from wastewater. The COD removal efficiency in CWs is higher than that in modified NWs, whereas the modified NWs can compensate for the deficiency of CWs where a stable and sufficient rhizosphere is not fully formed in the start-up period. All removal rates of COD, TN, and TP in CWs and modified NWs vary from 50 to 70%, while the total removal rate of COD, TN, and TP in IWS is about 85–90%. The operational results show that the maximum area loading of organic pollutants in modified NWs (65kg/had) is slightly higher than the empirical one (60kg/had) recommended by for free water surface wetlands. [ABSTRACT FROM AUTHOR]

Abstract: Dumbbell-shaped barium carbonate superstructures were successfully synthesized in the aqueous system containing egg albumin and ethylenediaminetetraacetate disodium (EDTA-2Na), employing BaCl2, NaHCO3 and NH3·H2O as the starting reagents. The as-prepared product was characterized by X-ray powder diffraction (XRD), energy dispersive spectrometry (EDS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Some factors influencing the morphology of BaCO3 crystals, such as the time, the amounts of egg albumin and EDTA-2Na, were studied. Experimental facts showed that a proper amount of egg albumin and EDTA-2Na played crucial roles in the formation of dumbbell-shaped BaCO3 superstructures. [Copyright &y& Elsevier]

Abstract: In the present paper, we reported the successful synthesis of dumbbell-like YF3 nanostructures with a high yield in a mixed system of water/N,N-dimethylformamide (DMF) under the assistance of ultrasound waves of 40kHz with the ultrasonic power of 100% (200W) at 65°C for 2h, employing Y2O3 (99.99%) and NH4F as the starting reactants. The product was characterized by means of powder X-ray diffraction (XRD), energy dispersive spectrometry (EDS), transmission electron microscopy (TEM), selected area electron diffraction (SAED) pattern and field-emission scanning electron microscopy (SEM). Some factors influencing the morphology of YF3 nanostructures, including the ultrasonic time and power, the amount of NH4F, and the ratio of water/DMF, were systematically investigated. Research showed that the morphology of YF3 could be tuned by the volume ratio of water/DMF. The roles of DMF and the ultrasonic wave in the formation of YF3 nanostructures were discussed. [Copyright &y& Elsevier]

Abstract: In the present paper, novel t-Se microspheres with holes were successfully prepared via a facile solution-phase approach at 150°C for 20h, employing SeO2 and glucose as reagents, poly(vinylpyrrolidone) (PVP) as the surfactant. The phase and morphology of the product were characterized by means of powder X-ray diffraction (XRD), energy dispersive spectrometry (EDS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). The conversion from α-Se to t-Se was investigated by a series of experiments and a possible formation process was suggested based on the experimental results. [Copyright &y& Elsevier]

Abstract: In this paper, we report the successful synthesis of NiTiO3 microtubes constructed by nearly spherical nanoparticles via a simple solution-combusting method employing a mixture of ethanol and ethyleneglycol (V/V=60/40) as the solvent, nickel acetate as the nickel source, tetra-n-butyl titanate as the titanium source and oxygen gas in the atmosphere as the oxygen source. The as-obtained product was characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), and energy dispersive X-ray spectrometry (EDS). The UV–vis absorption spectrum of the product showed two absorption peaks centered at 258.6 and 350.1nm, respectively. The Brunauer–Emmett–Teller (BET) surface area of the product was 14.06m2/g and the pore size distribution mainly located from 20 to 30nm. The photocatalytic degradation property of the product for organic dyes showed that the as-obtained porous NiTiO3 microtubes could strongly promote the degradation of organic dyes including Pyronine B, Safranine T and Fluorescein. [Copyright &y& Elsevier]

We report the successful preparation of flower-like ZnO microstructures in one step by a simple, rapid and reliable ultrasound irradiation route, using only Zn(CH3COO)2 and NaOH as starting materials. The product was characterized by powder X-ray diffraction, energy-dispersive X-ray spectrometry, transmission electron microscopy and scanning electron microscopy. The UV–vis absorption and emission spectra, photocatalytic activity and electrochemical properties of the as-obtained flower-like ZnO microstructures were studied. [Copyright &y& Elsevier]

Abstract: Barium carbonate crystals with higher-order superstructures have been successfully synthesized in a simple aqueous system containing a general polymer, polyacrylamide (PAM) at room temperature. BaCl2, NaHCO3 and NH3·H2O were used as the starting reagents. The X-ray powder diffraction (XRD) analysis showed the product was the orthorhombic BaCO3. Scanning electron microscopy (SEM) observations showed that higher-order superstructures were formed by the self-assembly of BaCO3 nanorods. Research showed that the morphology of the as-synthesized BaCO3 crystals could gradually evolve with the reaction time. Also, the morphology of BaCO3 crystals was affected by the initial concentrations of reactants: lower concentrations were used for the formation of dumbbell-shaped BaCO3 crystals. Based on the experimental results, a possible formation mechanism of BaCO3 superstructures was discussed. [Copyright &y& Elsevier]

Abstract: In the present paper, we successfully prepared PbTe nanocrystals in a simple aqueous system via the hydrothermal route employing PbO, Te powders and N2H4·H2O as the starting reactants at 150°C for 14h. Some factors affecting the morphologies of the PbTe nanocrystals, such as the reaction temperature, time, the amount of NaOH, sorts of reductants and Pb2+ ion sources, were systematically investigated. Experimental results indicated that, under keeping the other experimental conditions constant: raising the reaction temperature, the shapes of the as-obtained PbTe hardly changed, while decreasing the temperature, some PbTe dendrites were obtained; the short reaction time availed to obtain cubes with a hole in the center of each face; more amounts of NaOH were favorable to the formation of regular PbTe nanocuboids. When NaBH4 was used as the reductant, a large amount of near spherical PbTe nanocrystals was produced; while NaH2PO2 was used, many PbTe crystals with hollow framework structures were obtained. When Pb(CH3COO)2 was used as the Pb2+ ion source, some dendrites made of many irregular particles were generated; while PbSO4 was employed, many PbTe nanocuboids were produced. A possible formation mechanism of PbTe nanocrystals was proposed based on the experimental results. [Copyright &y& Elsevier]

In the present work, we report the successful preparation of columnar hexagonal-shaped ZnO crystals in one step by a simple, rapid and reliable microwave irradiation route, using Zn(CH3COO)2, hexamethylenetetramine, acrylamide and 2,2′-azo-bis-iso-butyronitrile as the starting materials. The in situ produced polyacrylamide acted as the surfactant directing the growth of ZnO crystals. The photocatalytic activity and electrochemical properties of the as-obtained columnar hexagonal-shaped ZnO crystals were studied. [Copyright &y& Elsevier]

Abstract: In the current paper, we successfully prepared lead sulfide (PbS) microcrystals with various shapes in a simple aqueous system using the hydrothermal synthesis route. Experimental results indicated that the change of the molar ratio of Pb2+/S2O3 2− could significantly influence the morphology of the product while keeping the other experimental conditions constant: with the decrease of the molar ratio of Pb2+/S2O3 2− from 1:1 to 1:4, the shape of the products varied from tri-prism, cube to magic-square structure. Changing the reaction temperature had big effect on the shape of the product: flower-shaped product was obtained at 80°C and cube-shaped products were produced at 120°C. When the reaction time varied, the shapes of the as-obtained PbS crystals also changed. At the same time, SEM observations showed that the counter-anions for Pb2+ could influence the shape of the product: Pb(NO3)2 being used as lead ion sources, most flower-shaped and few cubic PbS crystals were produced; while PbSO4 as lead ion source, the PbS cubes were obtained. An evolution process was described based on experimental facts. [Copyright &y& Elsevier]

ZnS nanoparticles about 3 nm in size were prepared by a simple, rapid and reliable route under microwave irradiation in a heterogeneous system, using ZnAc2·2H2O (Ac&z.dbnd6;CH3COO) and Na2S·9H2O as the starting materials, ethylene glycol (EG) as the medium. The product was characterized with X-ray powder diffraction (XRD), transmission electron microscopy (TEM) and ED, respectively. The optical properties of ZnS nanoparticles were studied. [Copyright &y& Elsevier]

Two different morphologies of Co nanostructures, such as hollow nanotubes and nanowires composed of nanowhiskers, have been prepared in a controllable fashion by using a pore-wall modified alumina membrane and adjusting electrodeposition parameters. The mechanism of formation of the Co nanostructures was also discussed. [Copyright &y& Elsevier]

An array of CdS nanotubes was successfully prepared in a porous anodic alumina (PAA) membrane under the assistance of microwave irradiation, employing CdCl2 and thiourea as the starting materials. TEM and SEM observations clearly showed the tubular structure of the product. SAED and XRD patterns showed the as-prepared product was non-crystalline, but EDX analysis confirmed the formation of CdS in the PAA membrane. [Copyright &y& Elsevier]

Highlights: [•] La-doped ZnO nanoparticles were successfully prepared via a simple solution-combustion route. [•] The integration of La3+ ions into ZnO decreased the band-gap of ZnO nanoparticles. [•] La-doped ZnO nanoparticles could remove more Pb and Cu ions from water resources than undoped ZnO. [ABSTRACT FROM AUTHOR]

Abstract: Sn1−x RE x O2−x/2 (RE=Y, La, Gd and Nd) nanorods have been prepared by annealing the as-obtained products from microwave-induced KCl-assisted solution combustion reaction. The phase evolution in the synthesis process was investigated by an X-ray diffractometer. Accordingly, the possible growth mechanism of Sn1−x RE x O2−x/2 nanorods was discussed based on oriented attachment by polar forces. The results showed that the Sn0.8Y0.2O1.9 nanorods were rutile-structured single crystals with 8–12nm diameter and 100–200nm length. Proper addition of KCl into the redox mixture solution is critical to the formation of Sn1−x RE x O2−x/2 nanorods. The approach is convenient, inexpensive and efficient for the high yield preparation of Sn1−x RE x O2−x/2 nanorods. [Copyright &y& Elsevier]

Abstract: The transport of dissolved inorganic nitrogen in wetlands was investigated in the Yeyahu National Preserve of Beijing, China, from July to December 2011. Stable isotope of nitrogen (15N) as NH4 + was added to experimental mesocosms vegetated by seven common wetland plants. The 15N abundance in soil and various plant parts were measured at prescribed time intervals during the 49-day experimental period. Rapid 15N enrichments were found in soil and aquatic plants during the first sampling event at day 3 and typically increased linearly during the experimental period. Highest 15N enrichment was found in submerged plants, followed by emergent plants and soil. No differences in δ 15N values were found among leaves and stems of all submerged plants (Potamogeton pusillus, Potamogeton perfoliatus, Najas marina, Ceratophyllum demersum), suggesting that these plant structures are equally effective in nitrogen assimilation. The roots of P. perfoliatus displayed the lowest enrichment compared to the stems and leaves. Such results indicate that submerged plant roots may have a relatively weak role in nitrogen assimilation. The two emergent plants (Phragmites australis and Typha orientalis) showed no differences in δ 15N values among all plant parts, suggesting rapid translocation of nitrogen from roots to other portions. This experiment demonstrates that wetland soil and plant stems and leaves are major sinks for dissolved nitrogen from the surface water and provides valuable insight into nitrogen retention and transport pathways in various wetland plants. [Copyright &y& Elsevier]

Abstract: CoSn(OH)6 nanocubes were rapidly prepared by a simple sonochemical route at room temperature for 30min, employing CoCl2, SnCl4 and NaOH as the starting reactants in the absence of any surfactant or template. Subsequently, CoSn(OH)6 nanocubes were converted into SnO2–Co3O4 hybrids by calcining at 500°C for 120min in air. Interestingly, the as-obtained SnO2–Co3O4 hybrids still kept the cubic morphology of CoSn(OH)6. The above samples were characterized by X-ray powder diffraction (XRD), field emission scanning electron microscopy (SEM), energy dispersive spectrometry (EDS), and (high resolution) transmission electron microscopy (HRTEM/TEM). Experiments showed that SnO2–Co3O4 hybrids owned the stronger photocatalytic activity for the degradation of methylene blue than CoSn(OH)6 nanocubes. [Copyright &y& Elsevier]

Abstract: In this paper, a two-step route was designed to prepare AgBr nanoparticles (NPs)-modified BiOBr nanoplates. Smooth BiOBr nanoplates were firstly synthesized through a simple hydrothermal method employing Bi(NO3)3 and KBr as the reactants in the absence of any surfactant or template; sequentially, smooth BiOBr nanoplates were immerged into a diluted AgNO3 solution to generate AgBr/BiOBr composite nanostructures based on ion exchanges. The as-obtained products were characterized by X-ray powder diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectrometry (EDS) and transmission electron microscopy (TEM). Photodegradation experiments showed that AgBr NPs-modified BiOBr nanoplates exhibited superior and better photocatalytic property compared with commercial P25 and pure BiOBr nanoplates. [Copyright &y& Elsevier]

Abstract: In this paper, we report the hydrothermal preparation of Cd(OH)2 nanowires and further conversion to CdO nanobelts, CdS nanowires and CdSe nanoparticles through thermal treatment, solvothermal and mixed-solvothermal routes, respectively. The as-obtained products were characterized by means of powder X-ray diffraction (XRD), transmission electron microscopy (TEM), and field emission scanning electron microscopy (FEMSEM). Research showed that four cadmium compounds were good photocatalysts for the degradation of organic dyes such as Safranine T and Pyronine B, under irradiation of 365nm UV light. The order of catalytic activity of different materials was found to be Cd(OH)2

Abstract: In this paper we reported the preparation of wrapped CuS nanowires via a simple hydrothermal reaction at 180 °C for 2 h, employing CuSO4·5H2O and thiourea as reactants in the absence of any structure-directing agent. SAED pattern showed that the wrapped CuS nanowires were polycrystalline, which was comprised of small nanoparticles. TEM observations showed that wrapped nanowires could grow and further transfer to hollow spheres with the prolonging of the reaction time from 2 h to 13. The UV–Vis spectra of CuS prepared at 180 °C for different times were studied. The possible transfer mechanism from wrapped nanowires to hollow spheres was suggested. [Copyright &y& Elsevier]

Abstract: CuO nanorods were obtained through the reaction of cupric dodecyl sulfate (Cu(DS)2) and NaOH at 80°C. The products were characterized by powder X-ray diffraction, transmission electron microscopy, selected area electron diffraction, X-ray photoelectron spectroscopy and UV–vis absorption spectroscopy. The probable mechanism of the formation of CuO nanorods was discussed. [Copyright &y& Elsevier]

Abstract: X-ray diffraction (XRD), temperature-programmed reduction (TPR) and X-ray photoelectron spectroscopy (XPS) were employed to investigate the dispersion of copper oxide in CuO/TiO2 samples prepared by one and double-step impregnations and the NO+CO activities of CuO/TiO2 samples were also tested. The results indicate that the dispersion capacity of copper oxide in CuO/TiO2 samples with one-step impregnation and double impregnations are about 0.52 and 0.98mmol/100m2 TiO2, respectively, which should be related to the shielding effect of accompanying NO3 − anions during the impregnations. Therefore, the dispersion capacity of copper oxide on anatase with double impregnations could approach to 1.16mmol/100m2 TiO2, i.e. a value corresponding to the density of vacant sites on the (001) surface of TiO2. The NO+CO activities of CuO/TiO2 samples suggest that dispersed copper oxide species in these catalysts is the mainly active species and the increasing amount of dispersed copper oxide would enhance their activities. It seems to suggest that, for the supported catalysts, double or multiple impregnations would result in better activity than those prepared by one-step impregnation. In addition, the coordination environment of the dispersed copper oxide species existed on the anatase surface has been discussed by the incorporation model [Y. Chen, L.F. Zhang, Catal. Lett. 12 (1992) 51]. [Copyright &y& Elsevier]

Abstract: A magnetite with high aspect ratio has been synthesized by a wet chemical process. A surfactant, polyethylene glycol, was used as the template, and a ferrous ammonia sulphate was used as iron source. In the one-step synthesis, a suitable ratio between the rates of deposition and oxidation of ferrous ions was achieved by adjusting the diffusion of ammonia and resulted in the iron oxide deposited with nanorod morphology. According to X-ray powder diffraction analysis, these nanorods crystallize in structure of magnetite phase. Transition electron microscopy and selected area electron diffraction investigations have revealed that nanorods are single crystal and up to 2000 nm long and their diameters generally range from 20 to 100 nm. The measurement by vibration sample magnetization shows the magnetization of the as-synthesized nanorods is higher than 50 emu/g. The presented one-step synthesis approach provides an advantageous access to large quantity of this important anisotropic nanomaterial. [Copyright &y& Elsevier]

Abstract: PbS nanocubes have been synthesized by one-step solid-state reaction between Pb(DS)2 (DS: dodecylsulfate anion) and Na2S·9H2O. The nanocrystals were characterized by X-ray powder diffraction, Transmission electron microscopy, UV–vis absorption spectrum and X-ray photoelectron spectra. The research showed that the functionized surfactant lead dodecyl sulfate (LDS) played an important role in the formation of PbS nanocubes. [Copyright &y& Elsevier]

Large-scale of long NbS2 nanowire strands were successfully synthesized by a catalyzed transport reaction involving C60. The strands have a diameter of 1–2 μm and length up to 0.5 mm, which are composed of single nanowire. The diameter of single nanowire is 1.6–20 nm. The products were characterized by powder X-ray diffraction, transmission electron microscopy, selected area electron diffraction, high-resolution transmission electron microscopy, scanning electron microscopy, and X-ray photoelectron spectroscopy. Probable mechanisms for catalytic growth were proposed. [Copyright &y& Elsevier]

In the current paper, the submicron Cu2O hollow spheres composed of small Cu2O nanoparticles of 22 nm in size were successfully prepared via using a multiple emulsion (O/W/O) system as the template. In this system, the interior oil phase was used as the core and exterior oil phase as the dispersion medium to prevent the product from aggregating; the reactants are dissolved in interim water layer. The liquid-droplet of the multiple emulsions plays a template and space-limiting role in addition to preventing the product from aggregation. [Copyright &y& Elsevier]

In the current paper, PbS micron crystals with a flower-like structure are reported via a simple aqueous-phase route under microwave irradiation, employing (CH3COO)2Pb, Na2S2O3 and H2O as the starting materials. No extra surfactants or templates were used. XRD and XPS analyses proved the formation of PbS in this simple system. The observations from TEM and SEM showed that the product composed of many flowers with micron size. Selected area electron diffraction (SAED) patterns confirmed that the micron flower was single crystal. Experiments showed that the Pb2+/S2O32− mole ratio influenced the morphology of the PbS micro-crystals. [Copyright &y& Elsevier]

Purpose: To investigate the effects of interferon-β-1a (IFN-β-1a) on the trafficking of cell populations in peripheral blood cells of multiple sclerosis (MS) patients. Methods: In this open-label pharmacodynamic study, peripheral blood was obtained from 10 relapsing–remitting (RR) MS patients just prior to and at 1, 2, 4, 8, 24, 48, 120, and 168 h after intramuscular injection of 30-μg IFN-β-1a. Timed samples were also obtained from five controls at 0, 8, 24, 48 and 168 h. The blood cells were analyzed using four-color flow cytometry with antibody conjugates directed against cell surface proteins specific for T cells, B cells, NK cells, and the activation marker, CD69. Results: IFN-β-1a treatment resulted in selective, time-dependent effects on many cell populations in peripheral blood. The trafficking of T-helper and T-suppressor/cytotoxic subsets of T cells were qualitatively different. The most prominent effects were on the trafficking of natural killer cells, the levels of which decreased to 23.5% of pretreatment values at 8 h after treatment. The levels of CD69-positive NK cells increased to a peak value of 606% of pretreatment levels at the 24-h time point. In untreated controls, these characteristic trafficking effects were not observed. There was inter-patient heterogeneity in the levels of activated NK cells at the 6-month time point that may potentially be relevant for individualizing IFN-β therapy. Conclusions: IFN-β treatment can induce specific, selective, and time-dependent trafficking of cells and its effects on different subsets of a given cell type are not qualitatively similar. The dynamics indicate that the activation of NK cells by IFN-β is possibly dependent on the trafficking of NK cells. The activated NK cell levels after prolonged therapy may potentially provide a surrogate marker for IFN-β exposure. [Copyright &y& Elsevier]

Amorphous rod-like and needle-like nanoparticles of cobalt disulfide were prepared by the reaction of CoCl2·6H2O with thiourea in the presence of some hydrazine in aqueous solution. The reaction was undertaken in an open reflux system at a relatively low temperature. Polycrystalline cobalt disulfide nanorods were obtained by a similar reaction in an alcohol/water mixed solution. The products were characterized by Fourier transform infrared spectrometer (FTIR), X-ray powder diffraction (XRD) and transmission electron microscopy (TEM). The effects of solvent, temperature and time of the reaction on the formation of cobalt disulfide nanocrystalline were discussed. It was found that hydrazine played an important role in shaping rod- or needle-like nanoparticles, and the reflux temperature and time mainly influenced the crystallization of nanoparticles. In addition, the microwave (wavelength λ=3 cm) absorption property of this nanocomposite at room temperature was also investigated. [Copyright &y& Elsevier]

Nanoparticles of Bi4Ti3O12 have been prepared by chemical coprecipitation. The phase structure was investigated by X-ray diffraction (XRD) and refined using the Rietveld method. Orthorhombic Bi4Ti3O12 particles were obtained after heating at 700 and 800 °C; however, for the particles calcined at 500–650 °C, the results suggested the presence of a high-temperature tetragonal phase at room temperature. This structural anomaly was further confirmed by differential thermal analysis (DTA). [Copyright &y& Elsevier]

Poly(N-vinyl-2-pyrrolidone) (PVP) cluster-assembled nanostructured films have been prepared by low energy cluster beam deposition method. TEM micrographs show that the films are assembled by spherical particles, which are distributed uniformly and randomly in the films. The pressure of helium carrier gas has a significant effect on the particle sizes and their distribution. Fourier transform infra-red and UV–Vis absorption spectra measurement have been performed so as to determine the structures and analyze the optical properties of the films. It is shown that the structural units of the nanoparticles of PVP cluster-assembled films are almost the same as that of original PVP. When compared to the original PVP casting film, PVP cluster-assembled film has 18 nm blue shift of maximum absorption and 0.67 eV blue shift of band gap. [Copyright &y& Elsevier]

Abstract: Rice-like α-Fe2O3 nanorods have been successfully synthesized by a simple microwave–hydrothermal route, employing FeCl3·6H2O and ethylenediamine (en) as the starting materials. The phase of the as-prepared product was characterized by X-ray powder diffraction and further determined by Rietveld refinement of XRD data. The morphology of the product was observed by field emission scanning electron microscopy (SEM) and (high-resolution) transmission electron microscopy (HR/TEM). The formation of Fe2O3 was further confirmed by energy dispersive X-ray spectrometry (EDS) and the Fourier transform infrared (FTIR) spectrum of the product. Experiments showed that the product possessed a high coercive force of 467.1Oe at room temperature, and exhibited a strong electrochemical response to Hg2+ ions in water resources. [Copyright &y& Elsevier]

The hollow Cu2−xS microspheres were successfully prepared via a novel template-free route in a simple system containing CuSO4, Na2S2O3 and H2O at the ambient conditions. A possible formation mechanism was proposed. [Copyright &y& Elsevier]