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
With the rapid development of the real economy and the renewal of personnel training requirements, the demand for mechanical and electrical professionals is becoming stronger and stronger, and the gap of mechanical an...With the rapid development of the real economy and the renewal of personnel training requirements, the demand for mechanical and electrical professionals is becoming stronger and stronger, and the gap of mechanical and electrical talents is also becoming larger and larger. In this regard, the traditional teaching methods can no longer meet the urgent needs of society and enterprises in the rapid training of electromechanical talents. In order to improve students' professional level and skills and quickly solve the shortage of talents, the Ministry of Education has also carried out relevant professional skills training courses in higher vocational schools across the country. Aiming at the current situation and existing problems of mechanical and electrical personnel training in higher vocational colleges, this paper makes research and analysis, and at the same time puts forward targeted improvement measures for the defects existing in the current mechanical and electrical education, aiming at constructing a systematic and scientific personnel training mode for higher vocational mechanical and electrical education.展开更多
Since the promulgation of the “National Implementation Plan of Vocational Education Reform”, vocational education has changed from scale development to quality improvement, and it has a long way to go to the spring ...Since the promulgation of the “National Implementation Plan of Vocational Education Reform”, vocational education has changed from scale development to quality improvement, and it has a long way to go to the spring of reform. Counselors in higher vocational colleges should adhere to the mission of educating people for the party and the country, uphold the concept of development, take students as the center, give full play to the leading role of ideological and political education, highlight the educational function of ideological and political education in the curriculum, practically promote the healthy development of ideological and political education in the curriculum, and realize the lofty goal of moral education.展开更多
With the deepening of the reform of the new curriculum standard in our country, the new curriculum standard also points out that in the teaching process, we should give full play to the role of open teaching model in ...With the deepening of the reform of the new curriculum standard in our country, the new curriculum standard also points out that in the teaching process, we should give full play to the role of open teaching model in middle school mathematics teaching. This new type of teaching method plays a great role in modern education and gradually receives the attention of some teachers. Therefore, in the process of middle school mathematics teaching, teachers should also adopt some open teaching methods to help students cultivate their awareness of excellence, encourage students to keep forging ahead, and improve students thinking ability and learning ability.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
The methods of X-ray diffraction (XRD) and ICP-AES are applied to analyzing the mineral composition of modern and fossil snail shells in Luochuan section and Xifeng section. The results show that the mineral phase of ...The methods of X-ray diffraction (XRD) and ICP-AES are applied to analyzing the mineral composition of modern and fossil snail shells in Luochuan section and Xifeng section. The results show that the mineral phase of calcium carbonate in modern snail shells is aragonite, but for some fossil snail shells in certain layers of loess sequences, a part of aragonite is transformed into calcite. In Luochuan and Xifeng sections, the stratigraphic borderline of arago- nite-calcite transformation appearing obviously is between L5 and L6. Under the earth surface condition, the arago- nite-calcite transformation is influenced by the factor of temperature only in a long time scale. It seems that the pres- sure is not the factor influencing the aragonite-calcite trans- formation. The results also show that existing age of snail shells is possibly the dominant and principal factor for the aragonite-calcite transformation. To a certain extent, the degree of aragonite-calcite transformation in snail shell is controlled by the content of trace element, such as Mg2+. The trace element can improve the stability of snail shell arago- nite and impede the process of aragonite transforming into calcite.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With the rapid development of the real economy and the renewal of personnel training requirements, the demand for mechanical and electrical professionals is becoming stronger and stronger, and the gap of mechanical and electrical talents is also becoming larger and larger. In this regard, the traditional teaching methods can no longer meet the urgent needs of society and enterprises in the rapid training of electromechanical talents. In order to improve students' professional level and skills and quickly solve the shortage of talents, the Ministry of Education has also carried out relevant professional skills training courses in higher vocational schools across the country. Aiming at the current situation and existing problems of mechanical and electrical personnel training in higher vocational colleges, this paper makes research and analysis, and at the same time puts forward targeted improvement measures for the defects existing in the current mechanical and electrical education, aiming at constructing a systematic and scientific personnel training mode for higher vocational mechanical and electrical education.
文摘Since the promulgation of the “National Implementation Plan of Vocational Education Reform”, vocational education has changed from scale development to quality improvement, and it has a long way to go to the spring of reform. Counselors in higher vocational colleges should adhere to the mission of educating people for the party and the country, uphold the concept of development, take students as the center, give full play to the leading role of ideological and political education, highlight the educational function of ideological and political education in the curriculum, practically promote the healthy development of ideological and political education in the curriculum, and realize the lofty goal of moral education.
文摘With the deepening of the reform of the new curriculum standard in our country, the new curriculum standard also points out that in the teaching process, we should give full play to the role of open teaching model in middle school mathematics teaching. This new type of teaching method plays a great role in modern education and gradually receives the attention of some teachers. Therefore, in the process of middle school mathematics teaching, teachers should also adopt some open teaching methods to help students cultivate their awareness of excellence, encourage students to keep forging ahead, and improve students thinking ability and learning ability.
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.
基金This work was supported by the National Key Program for Basic Research(Grant No.2001 CCB00100)the Key Pro-gram of National Natural Science Foundation of China(Grant No:4033 1001)the National Basic Research Program of China(Grant No:2004CB720204).
文摘The methods of X-ray diffraction (XRD) and ICP-AES are applied to analyzing the mineral composition of modern and fossil snail shells in Luochuan section and Xifeng section. The results show that the mineral phase of calcium carbonate in modern snail shells is aragonite, but for some fossil snail shells in certain layers of loess sequences, a part of aragonite is transformed into calcite. In Luochuan and Xifeng sections, the stratigraphic borderline of arago- nite-calcite transformation appearing obviously is between L5 and L6. Under the earth surface condition, the arago- nite-calcite transformation is influenced by the factor of temperature only in a long time scale. It seems that the pres- sure is not the factor influencing the aragonite-calcite trans- formation. The results also show that existing age of snail shells is possibly the dominant and principal factor for the aragonite-calcite transformation. To a certain extent, the degree of aragonite-calcite transformation in snail shell is controlled by the content of trace element, such as Mg2+. The trace element can improve the stability of snail shell arago- nite and impede the process of aragonite transforming into calcite.
