A pilot-scale multilayer rapid infiltration system (MRIS) for domestic wastewater treatment was e... more A pilot-scale multilayer rapid infiltration system (MRIS) for domestic wastewater treatment was established and efficient removal of ammonia and chemical oxygen demand (COD) was achieved in this study. The microbial community composition and abundance of ammonia oxidizers were investigated. Efficient biofilms of ammonia oxidizers in the stationary phase (packing material) was formed successfully in the MRIS without special inoculation. DGGE and phylogenetic analyses revealed that proteobacteria dominated in the MRIS. Relative abundance of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) showed contrary tendency. In the flowing phase (water effluent), AOA diversity was significantly correlated with the concentration of dissolve oxygen (DO), NO3-N and NH3-N. AOB abundance was significantly correlated with the concentration of DO and chemical oxygen demand (COD). NH3-N and COD were identified as the key factors to shape AOB community structure, while no variable sig...
Layer based rapid fabrication technologies have seen rapid progress in recent years in terms of b... more Layer based rapid fabrication technologies have seen rapid progress in recent years in terms of both material choices and part accuracy. Given the great progress, such technologies still have difficulties in meeting the accuracy requirements of functional parts such as mechanisms with joints. In mechanism fabrication, one of the critical factors is the joint clearance. With the limited accuracy of
TiNi alloy, especially porous TiNi, a good biocompatible material, can be made by laser induced s... more TiNi alloy, especially porous TiNi, a good biocompatible material, can be made by laser induced self-propagating high-temperature synthesis (SHS). A 40-W CO2 laser was used to ignite the powders of Ti and Ni, and TiNi intermetallic compound was synthesized by SHS in a reaction kettle of stainless steel. High-speed photography, X-ray diffraction, and scanning electron microscopy were used to investigate
Semantic Web organizes voluminous data on Internet in a machine-understandable manner, which sati... more Semantic Web organizes voluminous data on Internet in a machine-understandable manner, which satisfies the continuously increasing requirements on data interoperation. In the context of Semantic Web, Ontology and RDF statements are widely used as a standard to describe semantic information of data. However, currently most of the web applications employ XML as a data media. XML can only describe the
Hierarchical ZnO microrods have been prepared by cetyltrimethylammonium bromide (CTAB)-assisted h... more Hierarchical ZnO microrods have been prepared by cetyltrimethylammonium bromide (CTAB)-assisted hydrothermal process at low temperature. Sheetlike or fluffy ZnO nanostructures have been developed in a large density on the surface of the microrods. The ZnO cores grow preferentially along [001]; the nanosheets are single crystalline and grow in two dimensions along the [001] and [120] directions. The formation of hierarchical
In this study polyaluminum chloride (PAC) has a high Alb content, 80.1%. It was the most efficien... more In this study polyaluminum chloride (PAC) has a high Alb content, 80.1%. It was the most efficient species of PAC. PAC was synthesized with a membrane reactor which made of a hollow-fiber (HF) ultrafiltration membrane (UFM). The UFM was made from PPESK, a novel membrane material with properties of excellent thermal, chemical and mechanical stability. In this reactor, a sodium
Clad layers using high power carbon dioxide laser and various powder compositions of W, C, Co and... more Clad layers using high power carbon dioxide laser and various powder compositions of W, C, Co and WC on carbon steel substrate have been investigated. Microstructures of the clad layers are greatly affected by the processing parameters: powder size; powder type; shielding gas; degree of dilution; and geometry of the clad layer. Clad layers with large WC particles in a
Using ethylene glycol methyl ether (EGME) or acetic acid (AA) as additives and N-methyl-2-pyrroli... more Using ethylene glycol methyl ether (EGME) or acetic acid (AA) as additives and N-methyl-2-pyrrolidone (NMP) as a solvent, defect-free skinned poly(phthalazinone ether sulfone ketone) (PPESK) hollow fiber asymmetric nanofiltration membranes were prepared by dry/wet phase inversion technique from 23wt.% solids of PPESK/additive/NMP solutions. The pure water was used as a coagulant media. The effects of non-solvent additive on the membrane
Twenty-four major and trace elements and the mineralogical composition of four sediment cores alo... more Twenty-four major and trace elements and the mineralogical composition of four sediment cores along the Pearl River and estuary were analyzed using ICP-AES, ICP-MS, and X-ray diffraction (XRD) to evaluate contamination levels. The dominant minerals were quartz, kaolinite, and illite, followed by montmorillonite and feldspars, while small amounts of halite and calcite were also observed in a few samples. Cluster analysis (CA) and principal component analysis (PCA) were performed to identify the element sources. The highest metal concentrations were found at Huangpu, primarily due to wastewater treatment plant discharge and/or the surreptitious dumping of sludge, and these data differed from those of other sources. Excluding the data from Huangpu, the PCA showed that most elements could be considered as lithogenic; few elements are the combination of lithogenic and anthropogenic sources. An antagonistic relationship between the anthropogenic source metals (K, Ba, Zn, Pb, Cd, Ag, Tl, a...
The biomaterial class of chitooligosaccharides (chitin), commonly found in insects and fungi, is ... more The biomaterial class of chitooligosaccharides (chitin), commonly found in insects and fungi, is one of the most abundant on earth. Substantial evidence implicates chitin in mediating a diverse array of plant cellular signaling events, including the induction of plant defense mechanisms against invading pests. However, these recognition and mediation mechanisms, including the binding kinetics between chitin and their plant recognition receptors, are not fully understood. Therefore, the creation of a platform capable of both interfacing with chitin and plant cell receptors, and monitoring their interactions, would significantly advance our understanding of this plant defense elicitor. Recently, a label-free, highly sensitive biosensor platform, based on Whispering Gallery Mode optical microresonators, has been developed to study such biomolecular interactions. Here, we demonstrate how this unique platform can be interfaced with chitin using simple carbohydrate chemistry. The surface chemistry is demonstrated using X-ray photoelectron spectroscopy, fluorescence microscopy, optical profilometry, ellipsometry, and contact angle measurements. The resulting surface is uniform, with an average surface roughness of 1.25 nm, and is active toward chitin recognition elements. Optical loss measurements using standard quantitative cavity analysis techniques demonstrate that the bioconjugated platforms maintain the high performance (Q > 10 6 ) required to track binding interactions in this system. The platform is able to detect lectin, which binds COs, at 10 g/mL concentration. This biosensor platform's unique capabilities for label-free, high sensitivity biodetection, when properly interfaced with the biomaterials of interest, could provide the basis for a robust analytical technique to probe the binding dynamics of chitin-plant cell receptors.
In this study, the contents, sources and accumulation rate of sedimentary organic matter (OM) in ... more In this study, the contents, sources and accumulation rate of sedimentary organic matter (OM) in the Pearl River Estuary (PRE) and adjacent coastal area were investigated. The stable carbon isotopic composition (δ13C) is a reliable geochemical proxy and was used to indicate the OM origin here. Nevertheless, the organic carbon and nitrogen molar ratios (TOC/TN) and the stable nitrogen isotopic
A ca. 600 m-long, 0.5-20 m-wide NW-SE trending granite dike crosscuts the high pressure-low tempe... more A ca. 600 m-long, 0.5-20 m-wide NW-SE trending granite dike crosscuts the high pressure-low temperature (HP-LT) Tianshan metamorphic belt, the foliation of which is parallel to the main ENE regional trend in the Chinese South Tianshan Orogen. It is mainly composed of plagioclase, K-feldspar, quartz, muscovite, biotite and secondary chlorite, while fluorite, zircon and xenotime occur as accessories. The immediate country rock is a quartz-biotite-plagioclase schist, which grades several tens of meters away from the granite dike into a chlorite-mica-albite schist. The latter schist is intimately intercalated with blueschist layers and boudins. The A/CNK value of the granite dike samples varies from 1.15 to 1.27 indicating a strongly peraluminous composition. CaO/Na 2 O ranges from 0.06 to 0.17 and Al 2 O 3 /TiO 2 from 240 to 525, similar to the ratios of strongly peraluminous (SP) granites exposed in 'high-pressure' collision zones such as the Himalayas. A zircon U-Pb age of 285 Ma was obtained for the granite dike, thus constraining the upper limit for the age of HP-LT metamorphism. The petrological and geochemical data suggest that the SP leucogranite dike intruded during the exhumation of overthickened crust in the post-collisional setting between the Yili (-Central Tianshan) and Tarim blocks. The dataset presented here in conjunction with previously published data corroborate that the HP-LT metamorphism must have occurred earlier than the Permian in the Tianshan Orogen. Therefore, the collision between the Yili (-Central Tianshan) and Tarim blocks and the final amalgamation of the Southwestern Altaids must have been terminated in Late Paleozoic and not in Triassic times as previously suggested.
Due to the high peroxidase-like activity and small lateral size of graphene quantum dots (GQDs), ... more Due to the high peroxidase-like activity and small lateral size of graphene quantum dots (GQDs), the covalently assembled GQDs/Au electrode exhibits great performance and stability in H(2)O(2) detection. It is better or comparable to some enzyme-immobilized electrodes, and thus could be useful in sensing H(2)O(2) changes in biological systems.
Total metal concentrations (Cr, Ni, Cu, Zn, and Pb), acid volatile sulfide and simultaneously ext... more Total metal concentrations (Cr, Ni, Cu, Zn, and Pb), acid volatile sulfide and simultaneously extracted metals (AVS-SEM), and heavy metal fractionation were used to assess the heavy metals contamination status and ecological risk in the sediments of the Pearl River Estuary (PRE) and adjacent shelf. Elevated concentrations at estuarine sites and lower concentrations at adjacent shelf sites are observed, especially for Cu and Zn. Within the PRE, the concentration of heavy metals in the western shore was mostly higher than that in the middle shore. The metals from anthropogenic sources mainly occur in the labile fraction and may be taken up by organisms as the environmental parameters change. A combination of total metal concentrations, metal contamination index and sequential extraction analysis is necessary to get the comprehensive information on the baseline, anthropogenic discharge and bioavailability of heavy metals.
Hollow fiber ultrafiltration membranes were prepared successfully from poly(phthalazinone ether s... more Hollow fiber ultrafiltration membranes were prepared successfully from poly(phthalazinone ether sulfone ketone) (PPESK) with a dry/wet phase inversion technique. Ethylene glycol methyl ether, diethylene glycol (DegOH) and methyl ethyl ketone were used as non-solvent additives and N-methyl-2-pyrrolidone used as a solvent in membrane preparation. The effects of PPESK concentration, the type of additives and the concentration of DegOH in casting
A pilot-scale multilayer rapid infiltration system (MRIS) for domestic wastewater treatment was e... more A pilot-scale multilayer rapid infiltration system (MRIS) for domestic wastewater treatment was established and efficient removal of ammonia and chemical oxygen demand (COD) was achieved in this study. The microbial community composition and abundance of ammonia oxidizers were investigated. Efficient biofilms of ammonia oxidizers in the stationary phase (packing material) was formed successfully in the MRIS without special inoculation. DGGE and phylogenetic analyses revealed that proteobacteria dominated in the MRIS. Relative abundance of ammonia-oxidizing archaea (AOA) and ammonia-oxidizing bacteria (AOB) showed contrary tendency. In the flowing phase (water effluent), AOA diversity was significantly correlated with the concentration of dissolve oxygen (DO), NO3-N and NH3-N. AOB abundance was significantly correlated with the concentration of DO and chemical oxygen demand (COD). NH3-N and COD were identified as the key factors to shape AOB community structure, while no variable sig...
Layer based rapid fabrication technologies have seen rapid progress in recent years in terms of b... more Layer based rapid fabrication technologies have seen rapid progress in recent years in terms of both material choices and part accuracy. Given the great progress, such technologies still have difficulties in meeting the accuracy requirements of functional parts such as mechanisms with joints. In mechanism fabrication, one of the critical factors is the joint clearance. With the limited accuracy of
TiNi alloy, especially porous TiNi, a good biocompatible material, can be made by laser induced s... more TiNi alloy, especially porous TiNi, a good biocompatible material, can be made by laser induced self-propagating high-temperature synthesis (SHS). A 40-W CO2 laser was used to ignite the powders of Ti and Ni, and TiNi intermetallic compound was synthesized by SHS in a reaction kettle of stainless steel. High-speed photography, X-ray diffraction, and scanning electron microscopy were used to investigate
Semantic Web organizes voluminous data on Internet in a machine-understandable manner, which sati... more Semantic Web organizes voluminous data on Internet in a machine-understandable manner, which satisfies the continuously increasing requirements on data interoperation. In the context of Semantic Web, Ontology and RDF statements are widely used as a standard to describe semantic information of data. However, currently most of the web applications employ XML as a data media. XML can only describe the
Hierarchical ZnO microrods have been prepared by cetyltrimethylammonium bromide (CTAB)-assisted h... more Hierarchical ZnO microrods have been prepared by cetyltrimethylammonium bromide (CTAB)-assisted hydrothermal process at low temperature. Sheetlike or fluffy ZnO nanostructures have been developed in a large density on the surface of the microrods. The ZnO cores grow preferentially along [001]; the nanosheets are single crystalline and grow in two dimensions along the [001] and [120] directions. The formation of hierarchical
In this study polyaluminum chloride (PAC) has a high Alb content, 80.1%. It was the most efficien... more In this study polyaluminum chloride (PAC) has a high Alb content, 80.1%. It was the most efficient species of PAC. PAC was synthesized with a membrane reactor which made of a hollow-fiber (HF) ultrafiltration membrane (UFM). The UFM was made from PPESK, a novel membrane material with properties of excellent thermal, chemical and mechanical stability. In this reactor, a sodium
Clad layers using high power carbon dioxide laser and various powder compositions of W, C, Co and... more Clad layers using high power carbon dioxide laser and various powder compositions of W, C, Co and WC on carbon steel substrate have been investigated. Microstructures of the clad layers are greatly affected by the processing parameters: powder size; powder type; shielding gas; degree of dilution; and geometry of the clad layer. Clad layers with large WC particles in a
Using ethylene glycol methyl ether (EGME) or acetic acid (AA) as additives and N-methyl-2-pyrroli... more Using ethylene glycol methyl ether (EGME) or acetic acid (AA) as additives and N-methyl-2-pyrrolidone (NMP) as a solvent, defect-free skinned poly(phthalazinone ether sulfone ketone) (PPESK) hollow fiber asymmetric nanofiltration membranes were prepared by dry/wet phase inversion technique from 23wt.% solids of PPESK/additive/NMP solutions. The pure water was used as a coagulant media. The effects of non-solvent additive on the membrane
Twenty-four major and trace elements and the mineralogical composition of four sediment cores alo... more Twenty-four major and trace elements and the mineralogical composition of four sediment cores along the Pearl River and estuary were analyzed using ICP-AES, ICP-MS, and X-ray diffraction (XRD) to evaluate contamination levels. The dominant minerals were quartz, kaolinite, and illite, followed by montmorillonite and feldspars, while small amounts of halite and calcite were also observed in a few samples. Cluster analysis (CA) and principal component analysis (PCA) were performed to identify the element sources. The highest metal concentrations were found at Huangpu, primarily due to wastewater treatment plant discharge and/or the surreptitious dumping of sludge, and these data differed from those of other sources. Excluding the data from Huangpu, the PCA showed that most elements could be considered as lithogenic; few elements are the combination of lithogenic and anthropogenic sources. An antagonistic relationship between the anthropogenic source metals (K, Ba, Zn, Pb, Cd, Ag, Tl, a...
The biomaterial class of chitooligosaccharides (chitin), commonly found in insects and fungi, is ... more The biomaterial class of chitooligosaccharides (chitin), commonly found in insects and fungi, is one of the most abundant on earth. Substantial evidence implicates chitin in mediating a diverse array of plant cellular signaling events, including the induction of plant defense mechanisms against invading pests. However, these recognition and mediation mechanisms, including the binding kinetics between chitin and their plant recognition receptors, are not fully understood. Therefore, the creation of a platform capable of both interfacing with chitin and plant cell receptors, and monitoring their interactions, would significantly advance our understanding of this plant defense elicitor. Recently, a label-free, highly sensitive biosensor platform, based on Whispering Gallery Mode optical microresonators, has been developed to study such biomolecular interactions. Here, we demonstrate how this unique platform can be interfaced with chitin using simple carbohydrate chemistry. The surface chemistry is demonstrated using X-ray photoelectron spectroscopy, fluorescence microscopy, optical profilometry, ellipsometry, and contact angle measurements. The resulting surface is uniform, with an average surface roughness of 1.25 nm, and is active toward chitin recognition elements. Optical loss measurements using standard quantitative cavity analysis techniques demonstrate that the bioconjugated platforms maintain the high performance (Q > 10 6 ) required to track binding interactions in this system. The platform is able to detect lectin, which binds COs, at 10 g/mL concentration. This biosensor platform's unique capabilities for label-free, high sensitivity biodetection, when properly interfaced with the biomaterials of interest, could provide the basis for a robust analytical technique to probe the binding dynamics of chitin-plant cell receptors.
In this study, the contents, sources and accumulation rate of sedimentary organic matter (OM) in ... more In this study, the contents, sources and accumulation rate of sedimentary organic matter (OM) in the Pearl River Estuary (PRE) and adjacent coastal area were investigated. The stable carbon isotopic composition (δ13C) is a reliable geochemical proxy and was used to indicate the OM origin here. Nevertheless, the organic carbon and nitrogen molar ratios (TOC/TN) and the stable nitrogen isotopic
A ca. 600 m-long, 0.5-20 m-wide NW-SE trending granite dike crosscuts the high pressure-low tempe... more A ca. 600 m-long, 0.5-20 m-wide NW-SE trending granite dike crosscuts the high pressure-low temperature (HP-LT) Tianshan metamorphic belt, the foliation of which is parallel to the main ENE regional trend in the Chinese South Tianshan Orogen. It is mainly composed of plagioclase, K-feldspar, quartz, muscovite, biotite and secondary chlorite, while fluorite, zircon and xenotime occur as accessories. The immediate country rock is a quartz-biotite-plagioclase schist, which grades several tens of meters away from the granite dike into a chlorite-mica-albite schist. The latter schist is intimately intercalated with blueschist layers and boudins. The A/CNK value of the granite dike samples varies from 1.15 to 1.27 indicating a strongly peraluminous composition. CaO/Na 2 O ranges from 0.06 to 0.17 and Al 2 O 3 /TiO 2 from 240 to 525, similar to the ratios of strongly peraluminous (SP) granites exposed in 'high-pressure' collision zones such as the Himalayas. A zircon U-Pb age of 285 Ma was obtained for the granite dike, thus constraining the upper limit for the age of HP-LT metamorphism. The petrological and geochemical data suggest that the SP leucogranite dike intruded during the exhumation of overthickened crust in the post-collisional setting between the Yili (-Central Tianshan) and Tarim blocks. The dataset presented here in conjunction with previously published data corroborate that the HP-LT metamorphism must have occurred earlier than the Permian in the Tianshan Orogen. Therefore, the collision between the Yili (-Central Tianshan) and Tarim blocks and the final amalgamation of the Southwestern Altaids must have been terminated in Late Paleozoic and not in Triassic times as previously suggested.
Due to the high peroxidase-like activity and small lateral size of graphene quantum dots (GQDs), ... more Due to the high peroxidase-like activity and small lateral size of graphene quantum dots (GQDs), the covalently assembled GQDs/Au electrode exhibits great performance and stability in H(2)O(2) detection. It is better or comparable to some enzyme-immobilized electrodes, and thus could be useful in sensing H(2)O(2) changes in biological systems.
Total metal concentrations (Cr, Ni, Cu, Zn, and Pb), acid volatile sulfide and simultaneously ext... more Total metal concentrations (Cr, Ni, Cu, Zn, and Pb), acid volatile sulfide and simultaneously extracted metals (AVS-SEM), and heavy metal fractionation were used to assess the heavy metals contamination status and ecological risk in the sediments of the Pearl River Estuary (PRE) and adjacent shelf. Elevated concentrations at estuarine sites and lower concentrations at adjacent shelf sites are observed, especially for Cu and Zn. Within the PRE, the concentration of heavy metals in the western shore was mostly higher than that in the middle shore. The metals from anthropogenic sources mainly occur in the labile fraction and may be taken up by organisms as the environmental parameters change. A combination of total metal concentrations, metal contamination index and sequential extraction analysis is necessary to get the comprehensive information on the baseline, anthropogenic discharge and bioavailability of heavy metals.
Hollow fiber ultrafiltration membranes were prepared successfully from poly(phthalazinone ether s... more Hollow fiber ultrafiltration membranes were prepared successfully from poly(phthalazinone ether sulfone ketone) (PPESK) with a dry/wet phase inversion technique. Ethylene glycol methyl ether, diethylene glycol (DegOH) and methyl ethyl ketone were used as non-solvent additives and N-methyl-2-pyrrolidone used as a solvent in membrane preparation. The effects of PPESK concentration, the type of additives and the concentration of DegOH in casting
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