In a re-study of regional geology by the China Geological Survey （CGS）, the key problem is in the stratigraphical division and correlation. According to the new isotopic dating of the Mesoand Neoproterozoic in China...In a re-study of regional geology by the China Geological Survey （CGS）, the key problem is in the stratigraphical division and correlation. According to the new isotopic dating of the Mesoand Neoproterozoic in China, there have been great changes in the strata correlation and tectonic explanation. The authors obtained four zircon sensitive high resolution ion micro-probe （SHRIMP） U- Pb datings from the bentonite of the Lengjiaxi Group （822±10 Ma, 823±12 Ma and 834±11 Ma） and Banxi Group （802.6±7.6 Ma） in north Hunan Province, which is considered to be the middle part of the Jiangnan Orogenic Belt. On the basis of the zircon dating mentioned above, the end of the Wuling orogen is first limited in the period from 822 Ma to 802 Ma in one continued outcrop （Lucheng section） in Linxiang city, Hunan Province. Combining a series of new zircon U-Pb datings in the Yangtze and Cathaysia blocks, several Neoproterozoic volcanic events and distribution of the metamorphic rocks in the Jiangnan Orogenic Belt have been distinguished. In the context of the global geodynamics, it is useful to set up a practical and high precision chronological framework and basic and unified late Precambrian section in South China.展开更多
In the pilot study of treating the purified terephthalic acid(PTA) wastewater with the functional Strain Fhhh in the carrier activated sludge process(CASP), the ratio of COD∶TN∶TP and the concentrations of Cu, Mn, S...In the pilot study of treating the purified terephthalic acid(PTA) wastewater with the functional Strain Fhhh in the carrier activated sludge process(CASP), the ratio of COD∶TN∶TP and the concentrations of Cu, Mn, Se and Zn were controlled to improve the manganese peroxidase(MnP) levels for increasing the treatment efficiency. When the ratio of COD∶TN∶TP was 100∶0.36∶0.15 and the concentrations of Cu, Mn, Se and Zn were 0.54, 5.07, 0.00 and 0.08 mg/L, the MnP specific activity(MnP-SA) reached 689 U/L, and the sludge loading rate to COD(SLRC) was 1.09 d -1, which was 4—7 fold of that in other processes reported. The data indicated that improving MnP level could enhance the degradability of Fhhh. And the potentials of Fhhh and CASP will be also discussed in this paper.展开更多
The chemical and physical properties of nitrogen and phosphorus as well as their concentrations in the over- lying water, pore-water and sediments in Huainan segment of the Huaihe river were analyzed. The chemical for...The chemical and physical properties of nitrogen and phosphorus as well as their concentrations in the over- lying water, pore-water and sediments in Huainan segment of the Huaihe river were analyzed. The chemical forms of phosphorus in sediments were differentiated by a sequential fraction method. The results revealed that the NH+4 -N content in pore-water of 6 surface sediments is obviously higher than that in overlying water, indicating that there is a dynamic tendency of releasing NH+4 -N from sediment into overlying water. Chemical compound of nitrogen differs among segments of the river, while phosphorus has no such difference. Calcium bound phosphate (Ca-P) and iron bound phosphate (Fe-P) accounts for 60 % of the total phosphorus, and occluded-P (O-P) accounts for less than 20 %. Our findings indicate that 1) industrial waste water and domestic sewage have contributed to the excessive nu- trient salts in Huaihe river, 2) decreased water flow during low water periods, and the interaction between sediments and overlying water disturbed by transport ships accelerate nutrient salt releasing into overlying water, which results in eutrophication of the river.展开更多
Paeonol was prepared by the extraction method from Moutan Cortex. Its crystal struc- ture was determined by single-crystal X-ray diffraction.The compound crystallizes in the monoclinic sys- tem, space group P21/...Paeonol was prepared by the extraction method from Moutan Cortex. Its crystal struc- ture was determined by single-crystal X-ray diffraction.The compound crystallizes in the monoclinic sys- tem, space group P21/c with a = 6.724(4), b = 8.792(6), c = 14.689(10) ?, β = 100.138(11)o, V = 854.8(10) ?3, Mr = 166.17, Z = 4, F(000) = 352, Dc = 1.291 g/cm3, μ = 0.097 mm-1, the final R = 0.0454 and wR = 0.0988 for 845 observed reflections with I > 2σ(I).展开更多
Arc Ion Plating can be used to synthesize multi-component composition gradient hard coatings by adjusting arc currents of metal targets. The present work aims at a comprehensive description of such a technique. The ex...Arc Ion Plating can be used to synthesize multi-component composition gradient hard coatings by adjusting arc currents of metal targets. The present work aims at a comprehensive description of such a technique. The examples of TiAl multi-layer alloy coatings and (Ti, M) N composition-gradient films were taken (M representing Zr, Nb etc.) for the purpose of explaining the working process and evaluating practical effects. The results show that this technique has the advantages of easy manipulation, rapid deposition, and wide composition range.展开更多
Objective: To evaluate the value of apparent diffusion coefficients (ADC) in Magnetic Resonance diffusion weighted imaging (MR DWI) with echo-planar technique in depicting the tumor cellularity and grading of astrocyt...Objective: To evaluate the value of apparent diffusion coefficients (ADC) in Magnetic Resonance diffusion weighted imaging (MR DWI) with echo-planar technique in depicting the tumor cellularity and grading of astrocytomas. Methods: Thirty-four patients with astrocytomas(18 male, 16 female, ages from 10-73 with average of 38.41) were examined by MRI and proved by surgery and pathology, and the number of grade Ⅰ-Ⅱ (low-grade) and grade Ⅲ-Ⅳ (high-grade) is 26 and 8 respectively. ADC values of astrocytomas were determined on MR DWI. Cellularity of astrocytomas was analyzed with Adobe Photoshop 7.0 software. Results: Mean ADC values of high-grade astrocytomas(7.34±2.95)×10^-4mm^2/s were significantly different from that of lowgrade astrocytomas(13.76±3.31)×10^-4mm^2/s (t=4.913, P<0.001). Cellularity of high-grade astrocytomas (19.81±9.73)% were significantly higher than that of low-grade astrocytomas (4.74±2.96)% (t=4.32,P=0.003). ADC values of astrocytomas significantly negatively correlated with their cellularities (r=-0.535, P=0.001). Conclusion: The cellularities of astrocytomas contribute very much to ADC values in MR DWI. MR DWI is very valuable in predicting and evaluating the cellularity of astrocytomas. MR DWI might have a potential in predicting the degree of astrocytomas.展开更多
The results of TEM investigation indicate that magnetite and maghemite are the major ferromagnetic minerals in loess-paleosol sequences. Primary magnetite has the similar morphology and surface characteristics as eoli...The results of TEM investigation indicate that magnetite and maghemite are the major ferromagnetic minerals in loess-paleosol sequences. Primary magnetite has the similar morphology and surface characteristics as eolian detrital particles. The magnetite can be classified into two categories, high-titanium and low-titanium, which may be the indicators of magmatic rocks and metamorphic rocks, respectively. TEM investigation at nanometer scale shows that primary detrital magnetite of micron scale had been partially weathered to maghemite of 5～20 nanometer during the pedogenic process, which maintain the pseudomorphism of the aeolian debris. Some chlorite particles were also weathered to nanometer scale magnetite or maghemite in the pedogenic process. So weathering of the two minerals leads to formation of superparamagnetism, which may be the important mechanism of magnetic-susceptibility increase in paleosols. The magnetite or maghemite resulting from the weathering of chlorite contains a small amount of P and S, which is the signal of microbe-mineral interaction, and indicates that microbes may play a certain role in chlorite weathering and formation of superparamagnetic particles.展开更多
基金supported by China Geological Survey(CGS) and IGMA 5000 (Grant No. 12120111200131)the ministry of Science and Technology (MST) (Grant No.,2011FY120100)
文摘In a re-study of regional geology by the China Geological Survey （CGS）, the key problem is in the stratigraphical division and correlation. According to the new isotopic dating of the Mesoand Neoproterozoic in China, there have been great changes in the strata correlation and tectonic explanation. The authors obtained four zircon sensitive high resolution ion micro-probe （SHRIMP） U- Pb datings from the bentonite of the Lengjiaxi Group （822±10 Ma, 823±12 Ma and 834±11 Ma） and Banxi Group （802.6±7.6 Ma） in north Hunan Province, which is considered to be the middle part of the Jiangnan Orogenic Belt. On the basis of the zircon dating mentioned above, the end of the Wuling orogen is first limited in the period from 822 Ma to 802 Ma in one continued outcrop （Lucheng section） in Linxiang city, Hunan Province. Combining a series of new zircon U-Pb datings in the Yangtze and Cathaysia blocks, several Neoproterozoic volcanic events and distribution of the metamorphic rocks in the Jiangnan Orogenic Belt have been distinguished. In the context of the global geodynamics, it is useful to set up a practical and high precision chronological framework and basic and unified late Precambrian section in South China.
基金Foundation item: The National Hi Tech Research and Development Program(863) of China(2001AA214191) and PhD Fund of the National Education Ministry of China(No. 20030284038)
文摘In the pilot study of treating the purified terephthalic acid(PTA) wastewater with the functional Strain Fhhh in the carrier activated sludge process(CASP), the ratio of COD∶TN∶TP and the concentrations of Cu, Mn, Se and Zn were controlled to improve the manganese peroxidase(MnP) levels for increasing the treatment efficiency. When the ratio of COD∶TN∶TP was 100∶0.36∶0.15 and the concentrations of Cu, Mn, Se and Zn were 0.54, 5.07, 0.00 and 0.08 mg/L, the MnP specific activity(MnP-SA) reached 689 U/L, and the sludge loading rate to COD(SLRC) was 1.09 d -1, which was 4—7 fold of that in other processes reported. The data indicated that improving MnP level could enhance the degradability of Fhhh. And the potentials of Fhhh and CASP will be also discussed in this paper.
基金Project 2003kj294 supported by natural science foundation of bureau education Anhui province
文摘The chemical and physical properties of nitrogen and phosphorus as well as their concentrations in the over- lying water, pore-water and sediments in Huainan segment of the Huaihe river were analyzed. The chemical forms of phosphorus in sediments were differentiated by a sequential fraction method. The results revealed that the NH+4 -N content in pore-water of 6 surface sediments is obviously higher than that in overlying water, indicating that there is a dynamic tendency of releasing NH+4 -N from sediment into overlying water. Chemical compound of nitrogen differs among segments of the river, while phosphorus has no such difference. Calcium bound phosphate (Ca-P) and iron bound phosphate (Fe-P) accounts for 60 % of the total phosphorus, and occluded-P (O-P) accounts for less than 20 %. Our findings indicate that 1) industrial waste water and domestic sewage have contributed to the excessive nu- trient salts in Huaihe river, 2) decreased water flow during low water periods, and the interaction between sediments and overlying water disturbed by transport ships accelerate nutrient salt releasing into overlying water, which results in eutrophication of the river.
文摘Paeonol was prepared by the extraction method from Moutan Cortex. Its crystal struc- ture was determined by single-crystal X-ray diffraction.The compound crystallizes in the monoclinic sys- tem, space group P21/c with a = 6.724(4), b = 8.792(6), c = 14.689(10) ?, β = 100.138(11)o, V = 854.8(10) ?3, Mr = 166.17, Z = 4, F(000) = 352, Dc = 1.291 g/cm3, μ = 0.097 mm-1, the final R = 0.0454 and wR = 0.0988 for 845 observed reflections with I > 2σ(I).
文摘Arc Ion Plating can be used to synthesize multi-component composition gradient hard coatings by adjusting arc currents of metal targets. The present work aims at a comprehensive description of such a technique. The examples of TiAl multi-layer alloy coatings and (Ti, M) N composition-gradient films were taken (M representing Zr, Nb etc.) for the purpose of explaining the working process and evaluating practical effects. The results show that this technique has the advantages of easy manipulation, rapid deposition, and wide composition range.
文摘Objective: To evaluate the value of apparent diffusion coefficients (ADC) in Magnetic Resonance diffusion weighted imaging (MR DWI) with echo-planar technique in depicting the tumor cellularity and grading of astrocytomas. Methods: Thirty-four patients with astrocytomas(18 male, 16 female, ages from 10-73 with average of 38.41) were examined by MRI and proved by surgery and pathology, and the number of grade Ⅰ-Ⅱ (low-grade) and grade Ⅲ-Ⅳ (high-grade) is 26 and 8 respectively. ADC values of astrocytomas were determined on MR DWI. Cellularity of astrocytomas was analyzed with Adobe Photoshop 7.0 software. Results: Mean ADC values of high-grade astrocytomas(7.34±2.95)×10^-4mm^2/s were significantly different from that of lowgrade astrocytomas(13.76±3.31)×10^-4mm^2/s (t=4.913, P<0.001). Cellularity of high-grade astrocytomas (19.81±9.73)% were significantly higher than that of low-grade astrocytomas (4.74±2.96)% (t=4.32,P=0.003). ADC values of astrocytomas significantly negatively correlated with their cellularities (r=-0.535, P=0.001). Conclusion: The cellularities of astrocytomas contribute very much to ADC values in MR DWI. MR DWI is very valuable in predicting and evaluating the cellularity of astrocytomas. MR DWI might have a potential in predicting the degree of astrocytomas.
基金supported by the Outstanding Overseas Chinese Scholars Fund of the Chinese Academy of Sciences(Grant No.2003-1-7)the National Natural Science Foundation of China(Grant Nos.40072017,40273002 and 40173003)the National Basic Research Development Program(Grant No.G1999043401).
文摘The results of TEM investigation indicate that magnetite and maghemite are the major ferromagnetic minerals in loess-paleosol sequences. Primary magnetite has the similar morphology and surface characteristics as eolian detrital particles. The magnetite can be classified into two categories, high-titanium and low-titanium, which may be the indicators of magmatic rocks and metamorphic rocks, respectively. TEM investigation at nanometer scale shows that primary detrital magnetite of micron scale had been partially weathered to maghemite of 5～20 nanometer during the pedogenic process, which maintain the pseudomorphism of the aeolian debris. Some chlorite particles were also weathered to nanometer scale magnetite or maghemite in the pedogenic process. So weathering of the two minerals leads to formation of superparamagnetism, which may be the important mechanism of magnetic-susceptibility increase in paleosols. The magnetite or maghemite resulting from the weathering of chlorite contains a small amount of P and S, which is the signal of microbe-mineral interaction, and indicates that microbes may play a certain role in chlorite weathering and formation of superparamagnetic particles.
