There are about 19 Neolithic Age sites and 120 Shang-Zhou dynasties sites in the western lakeshore of Chaohu Lake,Anhui Province,China.Based on sites data,topographic data,drainage maps,administrative maps and SPOT5 r...There are about 19 Neolithic Age sites and 120 Shang-Zhou dynasties sites in the western lakeshore of Chaohu Lake,Anhui Province,China.Based on sites data,topographic data,drainage maps,administrative maps and SPOT5 remote sensing data,spatial analysis methods were introduced into the archaeology of Chaohu Lake Basin with Geographic Information System(GIS).The spatial analysis methods include:1) Point Density Analysis with density model to acquire the shift of the sites;2) Distance Analysis to reveal the spatial structure of the sites;3) 3D Analysis based on Digital Elevation Model to get micro-geomorphologic features of the sites;and 4) Buffer Analysis to discover the relationship between the sites and rivers.The results indicate that the archaeological sites spread from the western lakeshore of Chaohu Lake gradually to the northwest,later to the south,and then symmetrically spread.Controlled by productive forces and other factors,ancient people preferred to reside in those places near water,or in plain and fertile land,which resulted in linear and decentralized distribution of the sites,and presented such disciplines as river valley directivity,terrace directivity and soil directivity.This paper indicates that the distribution of archaeological sites was influenced earlier by natural elements and later by human elements in the study period.The research is important for the integration of GIS and archaeology.展开更多
The operation principle of a novel portable oil ingredient instrument is introduced. Using the theory of fluorescence measurement, this instrument can carry out fast and consecutive in-situ detection of oil ingredient...The operation principle of a novel portable oil ingredient instrument is introduced. Using the theory of fluorescence measurement, this instrument can carry out fast and consecutive in-situ detection of oil ingredient in sea water, confirming fast and correctly the situation of oil contamination such as the concentration and the area, etc. The lowest detectable concentration for the instrument is 1×10 -8 g/ml with the precision of less than 3 %. The results of experiment and practice show that this system has well water-sealed characteristic and repeatability.展开更多
The Yangzi Petrochemical Company has successfully imple-mented the test commissioning of a 45 t/h pressure filter (base on dry feed material) installed in the PTA unit with its pressure filter technique commanding a l...The Yangzi Petrochemical Company has successfully imple-mented the test commissioning of a 45 t/h pressure filter (base on dry feed material) installed in the PTA unit with its pressure filter technique commanding a leading展开更多
A novel multi-tube photoreactor with 0.0188m3 valid reaction volume was constructed in pilot-scale. This rectangular reactor consisted of 13 regularly distributed silica glass tubes coating with TiO2 thin film photo-c...A novel multi-tube photoreactor with 0.0188m3 valid reaction volume was constructed in pilot-scale. This rectangular reactor consisted of 13 regularly distributed silica glass tubes coating with TiO2 thin film photo-catalyst. Total active area of TiO2 thin film is 0.3916m2. The ratio of surface area to volume achieves 20.8m-1. Photocatalytic experiment of phenol red demonstrates that the apparent reaction rate constant (k) is 0.074 65 h-1 and 0.16502h-1 for reaction system with and without micro-bubbles mixing. The corresponding apparent quantum efficiency (a) is 8.1771 X 10-7g.J-1 and 4.9036 x 10-7g-J-1, respectively. COD value of reactant could decrease to 17mg.L-1 and high performance liquid chromatography (HPLC) only shows two absorption peaks in 24 h pho-tocatalytic process time, so this photoreactor has good photomineralization effect. Experimental results reveal that photocatalytic destruction of organics is possible by using the multi-tube photoreactor.展开更多
The increased production and price of rare earth elements(REEs) are indicative of their importance and of growing global attention. More accurate and practical exploration procedures are needed for REEs, and for other...The increased production and price of rare earth elements(REEs) are indicative of their importance and of growing global attention. More accurate and practical exploration procedures are needed for REEs, and for other geochemical resources. One such procedure is a multivariate approach. In this study, five classifiers, including multilayer perceptron(MLP), Bayesian, k-Nearest Neighbors(KNN), Parzen, and support vector machine(SVM),were applied in supervised pattern classification of bulk geochemical samples based on REEs, P, and Fe in the Kiruna type magnetite-apatite deposit of Se-Chahun,Central Iran. This deposit is composed of four rock types:(1) High anomaly(phosphorus iron ore),(2) Low anomaly(metasomatized tuff),(3) Low anomaly(iron ore), and(4)Background(iron ore and others). The proposed methods help to predict the proper classes for new samples from the study area without the need for costly and time-consuming additional studies. In addition, this paper provides a performance comparison of the five models. Results show that all five classifiers have appropriate and acceptable performance. Therefore, pattern classification can be used for evaluation of REE distribution. However, MLP and KNN classifiers show the same results and have the highest CCRs in comparison to Bayesian, Parzen, and SVM classifiers. MLP is more generalizable than KNN and seems to be an applicable approach for classification and predictionof the classes. We hope the predictability of the proposed methods will encourage geochemists to expand the use of numerical models in future work.展开更多
This study carried out full-scale gas water heater combustion experiments and adopted FDS (fire dynamics simulator) to simulate three scenarios--different balcony environments when using water heater, such as airtig...This study carried out full-scale gas water heater combustion experiments and adopted FDS (fire dynamics simulator) to simulate three scenarios--different balcony environments when using water heater, such as airtight balcony, indoor door with openings and force ventilation to compare with full-scale combustion experiments. According to FDS simulation results, 02, CO and CO2 simulation concentration value correspond with full-scale experimental results. When the indoor O2 concentration was lower than 15%, which causes incomplete combustion, the CO concentration would rise rapidly and even reached above 1,500 ppm, causing death in short time. In addition, when the force ventilation model supplied the water heater with enough air to bum, the indoor CO concentration will keep low and harmless to humans. The study also adopted diverse variables, such as the opening area of window, outdoor wind speed and water heater types, to analyze deeply user's safety regarding gas water heater. In a result, while balcony area is larger than 14 mE, the volume of water heater is below 16 L (33.1 kW), and the indoor window, connecting balcony with room, is closed, if the opening on the outdoor window of the balcony is larger than 0.2 mE, this can ensure the personal security of the indoor space.展开更多
The presented results are related to the leaching of Pb-Zn-Cu-Fe sulphide concentrate, obtained from barite-sulphide ores, under the elevated temperatures and pressures in an autoclave. The leaching process was perfor...The presented results are related to the leaching of Pb-Zn-Cu-Fe sulphide concentrate, obtained from barite-sulphide ores, under the elevated temperatures and pressures in an autoclave. The leaching process was performed using the sulphur acid solution with the oxygen addition for the separation of the targeted metals from the polymetallic concentrate. In this process influences of various parameters were discussed and then correlated to the leached metals, zinc, copper and iron. Zinc, copper and iron were dissolved in a solution, while lead remained as insoluble in the leach residue. The best leaching results were determined under the temperature of 210 ℃ during the 240 min. Obtained leaching degrees were 98% zinc, 95% copper and 96% iron.展开更多
The quest for materials and devices that are capable of controlling heat flux continues to fuel research on thermal controlling devices. In this letter, using molecular dynamics simulations, we demonstrate that a part...The quest for materials and devices that are capable of controlling heat flux continues to fuel research on thermal controlling devices. In this letter, using molecular dynamics simulations, we demonstrate that a partially clamped singlelayer graphene can serve as a thermal modulator. The mismatch in phonon dispersion between the unclamped and clamped graphene sections results in phonon interface scattering, and the strength of interface scattering is tunable by controlling the clamp-graphene distance via applying the external pressure. Owing to the ultra-thin structure of graphene and its highly sensitive phonon dispersion to external physical interaction, the modulation efficiency--which is defined as the ratio of the highest to lowest heat flux-can reach as high as 150% at a moderate pressure of 50 GPa. This modulation efficiency can be further enhanced by arranging a number of clamps in series along the direction of the heat flux.展开更多
基金Under the auspices of National Natural Science Foundation of China (No 40571162)Education Department of Anhui Province Foundation (No 2007sk097)Natural Science Foundation of Anhui (No 090415212),Program for Innovative Research Team in Anhui Normal University
文摘There are about 19 Neolithic Age sites and 120 Shang-Zhou dynasties sites in the western lakeshore of Chaohu Lake,Anhui Province,China.Based on sites data,topographic data,drainage maps,administrative maps and SPOT5 remote sensing data,spatial analysis methods were introduced into the archaeology of Chaohu Lake Basin with Geographic Information System(GIS).The spatial analysis methods include:1) Point Density Analysis with density model to acquire the shift of the sites;2) Distance Analysis to reveal the spatial structure of the sites;3) 3D Analysis based on Digital Elevation Model to get micro-geomorphologic features of the sites;and 4) Buffer Analysis to discover the relationship between the sites and rivers.The results indicate that the archaeological sites spread from the western lakeshore of Chaohu Lake gradually to the northwest,later to the south,and then symmetrically spread.Controlled by productive forces and other factors,ancient people preferred to reside in those places near water,or in plain and fertile land,which resulted in linear and decentralized distribution of the sites,and presented such disciplines as river valley directivity,terrace directivity and soil directivity.This paper indicates that the distribution of archaeological sites was influenced earlier by natural elements and later by human elements in the study period.The research is important for the integration of GIS and archaeology.
文摘The operation principle of a novel portable oil ingredient instrument is introduced. Using the theory of fluorescence measurement, this instrument can carry out fast and consecutive in-situ detection of oil ingredient in sea water, confirming fast and correctly the situation of oil contamination such as the concentration and the area, etc. The lowest detectable concentration for the instrument is 1×10 -8 g/ml with the precision of less than 3 %. The results of experiment and practice show that this system has well water-sealed characteristic and repeatability.
文摘The Yangzi Petrochemical Company has successfully imple-mented the test commissioning of a 45 t/h pressure filter (base on dry feed material) installed in the PTA unit with its pressure filter technique commanding a leading
基金Supported by the Natural Science Foundation of Jiangsu Province (JH01-010).
文摘A novel multi-tube photoreactor with 0.0188m3 valid reaction volume was constructed in pilot-scale. This rectangular reactor consisted of 13 regularly distributed silica glass tubes coating with TiO2 thin film photo-catalyst. Total active area of TiO2 thin film is 0.3916m2. The ratio of surface area to volume achieves 20.8m-1. Photocatalytic experiment of phenol red demonstrates that the apparent reaction rate constant (k) is 0.074 65 h-1 and 0.16502h-1 for reaction system with and without micro-bubbles mixing. The corresponding apparent quantum efficiency (a) is 8.1771 X 10-7g.J-1 and 4.9036 x 10-7g-J-1, respectively. COD value of reactant could decrease to 17mg.L-1 and high performance liquid chromatography (HPLC) only shows two absorption peaks in 24 h pho-tocatalytic process time, so this photoreactor has good photomineralization effect. Experimental results reveal that photocatalytic destruction of organics is possible by using the multi-tube photoreactor.
文摘The increased production and price of rare earth elements(REEs) are indicative of their importance and of growing global attention. More accurate and practical exploration procedures are needed for REEs, and for other geochemical resources. One such procedure is a multivariate approach. In this study, five classifiers, including multilayer perceptron(MLP), Bayesian, k-Nearest Neighbors(KNN), Parzen, and support vector machine(SVM),were applied in supervised pattern classification of bulk geochemical samples based on REEs, P, and Fe in the Kiruna type magnetite-apatite deposit of Se-Chahun,Central Iran. This deposit is composed of four rock types:(1) High anomaly(phosphorus iron ore),(2) Low anomaly(metasomatized tuff),(3) Low anomaly(iron ore), and(4)Background(iron ore and others). The proposed methods help to predict the proper classes for new samples from the study area without the need for costly and time-consuming additional studies. In addition, this paper provides a performance comparison of the five models. Results show that all five classifiers have appropriate and acceptable performance. Therefore, pattern classification can be used for evaluation of REE distribution. However, MLP and KNN classifiers show the same results and have the highest CCRs in comparison to Bayesian, Parzen, and SVM classifiers. MLP is more generalizable than KNN and seems to be an applicable approach for classification and predictionof the classes. We hope the predictability of the proposed methods will encourage geochemists to expand the use of numerical models in future work.
文摘This study carried out full-scale gas water heater combustion experiments and adopted FDS (fire dynamics simulator) to simulate three scenarios--different balcony environments when using water heater, such as airtight balcony, indoor door with openings and force ventilation to compare with full-scale combustion experiments. According to FDS simulation results, 02, CO and CO2 simulation concentration value correspond with full-scale experimental results. When the indoor O2 concentration was lower than 15%, which causes incomplete combustion, the CO concentration would rise rapidly and even reached above 1,500 ppm, causing death in short time. In addition, when the force ventilation model supplied the water heater with enough air to bum, the indoor CO concentration will keep low and harmless to humans. The study also adopted diverse variables, such as the opening area of window, outdoor wind speed and water heater types, to analyze deeply user's safety regarding gas water heater. In a result, while balcony area is larger than 14 mE, the volume of water heater is below 16 L (33.1 kW), and the indoor window, connecting balcony with room, is closed, if the opening on the outdoor window of the balcony is larger than 0.2 mE, this can ensure the personal security of the indoor space.
文摘The presented results are related to the leaching of Pb-Zn-Cu-Fe sulphide concentrate, obtained from barite-sulphide ores, under the elevated temperatures and pressures in an autoclave. The leaching process was performed using the sulphur acid solution with the oxygen addition for the separation of the targeted metals from the polymetallic concentrate. In this process influences of various parameters were discussed and then correlated to the leached metals, zinc, copper and iron. Zinc, copper and iron were dissolved in a solution, while lead remained as insoluble in the leach residue. The best leaching results were determined under the temperature of 210 ℃ during the 240 min. Obtained leaching degrees were 98% zinc, 95% copper and 96% iron.
文摘The quest for materials and devices that are capable of controlling heat flux continues to fuel research on thermal controlling devices. In this letter, using molecular dynamics simulations, we demonstrate that a partially clamped singlelayer graphene can serve as a thermal modulator. The mismatch in phonon dispersion between the unclamped and clamped graphene sections results in phonon interface scattering, and the strength of interface scattering is tunable by controlling the clamp-graphene distance via applying the external pressure. Owing to the ultra-thin structure of graphene and its highly sensitive phonon dispersion to external physical interaction, the modulation efficiency--which is defined as the ratio of the highest to lowest heat flux-can reach as high as 150% at a moderate pressure of 50 GPa. This modulation efficiency can be further enhanced by arranging a number of clamps in series along the direction of the heat flux.