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1.
Dong WANG Shaoming PAN Jichun WU Qingping ZHU Chang LIU 《中国地球化学学报》2006,25(B08):168-169
In the history, the Yellow River nurtured Chinese civilization. It is respected as the ＂ancestor of the four large rivers in China＂ and praised as ＂the mother river of China＂. At the same time, the Yellow River is regarded as ＂the misery of China＂ and considered as the most complex river hard to control in the world. Today, the Yellow River is also one large river greatly influenced by human activities in the world. The safety of the Yellow River, particularly flood control, is always the most important issue for governing and developing the country. Great achievements have been made after many years of efforts for controlling the Yellow River. However, since the nineties of 20 century, some new problems occurred, such as sharp reduction of flux to sea, dry rivercourse, worsen environment, etc. Rapidly shrinking riverbed and two-level perched stream are disadvantageous to flood safety especially. The new concepts and new practices are urgently needed to control the river. Therefore, the Yellow River Conservancy Committee of Ministry of Water Resources had continuously carded out flow and sediment diversion each year from 2002 to 2005. To timely probe into the new issues produced after flow and sediment diversion, and in order to deepen the understanding of rules for the Yellow River＇s water and sediment and provide reference and experience to the researchers for other large rivers, five hydrologic and hydraulic characteristics of the Yellow River, such as lack of water, much of sediment, different resources of water and sediment, inconsistency between water and sediment and frequency of sink switching and route changing, are described. Flow and sediment diversion of the Yellow River is also reviewed. Under flow and sediment diversion, 相似文献
2.
Cascaded Evolution of Mantle Plumes and Metallogenesis of Core- and Mantle-derived Elements 总被引：1，自引：0，他引：1
NIU Shuyin HOU Quanlin HOU Zengqian SUN Aiqun WANG Baode LI Hongyang XU Chuanshi Institute of Geology Geological Survey Shijiazhuang College of Economics Shijiazhuang Hebei Institute of Geophysics Chinese Academy of Sciences Beijing Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 《《地质学报》英文版》2003,77(4):522-536
Mineral deposits are unevenly distributed in the Earth's crust, which is closely related to the formation and evolution of the Earth. In the early history of the Earth, controlled by the gravitational contraction and thermal expansion, lighter elements, such as radioactive, halogen-family, rare and rare earth elements and alkali metals, migrated upwards; whereas heavier elements, such as iron-family and platinum-family elements, base metals and noble metals, had a tendency of sinking to the Earth's core, so that the elements iron, nickel, gold and silver are mainly concentrated in the Earth's core. However, during the formation of the stratified structure of the Earth, the existence of temperature, pressure and viscosity differences inside and outside the Earth resulted in vertical material movement manifested mainly by cascaded evolution of mantle plumes in the Earth. The stratifications and vertical movement of the Earth were interdependent and constituted the motive force of the mantle-core movement. 相似文献
3.
Xiao Linping Testing Centre of Geotechnical Engineering Southwest Jiaotong Universityand Zhao YuguangChengdu Institute of Mineral Resources Chinese Academy of Geological Sciences Chengdu Sichuan Liu Xinzhu 《《地质学报》英文版》1997,71(4):386-394
This paper discusses the geological characteristics and architectures of sequence boundaries and their vicinities and has proposed a classification scheme for the sequence boundaries, which can thus be grouped into three types and eight categories: type I includes exposed truncated surface, palaeosol surface, palaeokarst surface and exposed surface; type Ⅱ boundaries include structural transitional surface during sea-level fall and transgressive onlap surface; and type Ⅲ includes submarine erosional diagenetic diastem and event surface. A study has been made for the three major boundaries lying between the Permian and pre-Permian, the Permian and Triassic, and the Middle and Lower Triassic respectively in terms of multiple disciplines such as lithostratigraphy, biostratigraphy, magnetostratigraphy and carbon and oxygen isotopic geology. These three boundaries are ascribed to type I , typeⅡ and typeⅢ, respectively. 相似文献
4.
Ying FU Shuili YU 《中国地球化学学报》2006,25(B08):149-150
Chemical coagulation is very important in water treatment, in which coagulant is an essential part. Pre-polymerized Al^3＋ and Fe^3＋ products have been used in practice, continuously spread for many years. However, iron-based coagulant has become the focus of studies due to cumulative biologic toxicity of residual Al in treated water. Polyferric sulfate （PFS） and poly-silicic-ferric sulfate （PSF） are all pre-polymerized polymers of Fe^3＋ salts. The hydrolysis process and species distribution of Fe^3＋ ions have been investigated extensively by many chemists and water-treatment specialists. Generally, the coagulation mechanism of conventional or pre-polymerized coagulants was often studied through jar-test, absorption experiment, microstructure observation or hydrolysis species indirectly. However, few researches have been done on the hydrolysis process of PSF in detail and on the study of the coagulation mechanism using its hydrolysis species distribution until now. In this work, PSF was prepared using water glass, ferrous sulfate and sodium chlorate by a copolymerization method. The hydrolysis species distribution was theoretically derived from pH variation during hydrolysis process of PSF compared to that of polyferric sulfate （PFS）, and then characteristics [morphology, species size, Zeta potential, spectra of X-ray diffraction and infrared spectra （IR）] and coagulation performances were explored between them. Coagulation mechanism was analyzed according to hydrolysis species distribution, characteristics and coagulation performances. The results showed that PSF gives different species distribution at different pH values and characteristics from those of PFS, leading to different coagulation mechanisms between the two coagulants. 相似文献
5.
V. S. Urusov N. A. Gromalova S. V. Vyatkin V. S. Rusakov V. V. Maltsev N. N. Eremin 《Moscow University Geology Bulletin》2011,66(2):102-107
Data on the structural and valence distribution of Cr and Fe in chrysoberyl and in alexandrite, its gem variety, are given.
It is shown that the Cr3+ line in the natural Ural and Tanzania samples is the strongest in the M1 site and for the synthetic stones, in the M2 site.
During the annealing of the alexandrite crystals, Cr3+ passes from the smaller M1 site into the larger M2 site. The M?ssbauer spectroscopy quantitatively determined the distribution
of different valence Fe ions. The various proportions of both Fe2+ and Fe3+ ions isomorphically entering the octahedral sites in the BeAl2O4 crystal structure were established. 相似文献
6.
This paper deals with a simulated test of biogenic mineralization made with a blue-green alga species,Spirulina platensix. The data in the experiment were recorded by a computerized surveying system. The influ-ence of algae on the accumulation of phosphorus by changing their microenvironment to promote the forma-tion and deposition of phosphate was studied. The results show that the pH value of cultural liquor rose up to 10 and the redox potential (Eh) may dropby 100-200 mV during the algal logarithmic growth stage, and the cultrual liquor was changed into a mediumwith a weakly reducing condition. At the end of the logarithmic growth stage white deposits of Na_2Ca(CO_3)_2·5H_2O and Ca_2Mg (PO_4)_2·2H_2O were formed on the floor of cultural containers. The test presented a wduableevidence for the theory of biogenic mineralization. 相似文献
7.
Liping ZHANG Rongshu ZENG 《中国地球化学学报》2006,25(B08):38-39
Three dumping sites have been formed at the northern region of Fushun City, Liaoning Province, for a large number of gangues including much oil shale that had been piled onto ground as gangue during long-term coal exploitation at West Fushun Open-pit Mine. Under appropriate conditions, self-combustion occurs after long-term exposure of oil shale and consequently such phenomena could be found almost everywhere at the three dumping sites. Much polycyclic aromatic hydrocarbons （PAHs） must be generated through oil shale self-combustion, a kind of incomplete combustion. In this paper, in order to make clear the PAHs distribution in oil shale and its self-combustion and their potential effects on surrounding environment, coal, low-grade oil shale, high-grade oil shale, burning oil shale, burnt oil shale and shaly soil collected from West Fushun Open-Pit Mine and West Dumping Site were analyzed quantitatively in 16 US EPA priority PAHs for the first time. Results showed that 16 PAHs in all samples were less than those in some bitumites and carbonaceous coals and were as much as those in lignites and anthracites from some Chinese mining areas. Coal and low-grade oil shale were abundant in lower molecular-weighted PAHs in contrast to high-grade oil shale with rich higher molecular-weighted PAHs. They had more benzo[a] pyrene than the highest background value in soils in Liaoning Province. So PAHs in these crude oil shales could cause potential effects on environment. There were at least 5121.40 p.g/kg PAils generated and at least 3976.70 μg/kg PAHs released into environment in the period from combustion beginning to sampling on the basis of calculation. Furthermore, the concentrations of 3-4 ring PAHs among them were very high. Therefore it could be said that oil shale self-combustion aggravated the environmental impacts of PAHs in oil shale. The low concentrations of PAHs in shaly soil showed that much PAHs had been released through recultivation and biodegradation. 相似文献
8.
The paper deals with the metallogenic conditions and regularities of the region ol the lower-middle reachesof the Changjiang River in China. The complicated structural network with the Changjiang (Yangtse) deepfracture as its trunk is the leading rock-and ore-controlling structure of the metallogenic belt. Thehigh-potassium granodiorites of the first magmatic sequence of the Mesozoic Yangtse syntexis type and thesodium-rich diorites of the second sequence are genetically related to the copper ore series and the iron ore se-ries respectively. and occur respectively in the block-faulted and-folded uplift area and the down-faulted vol-canic basin as well as the transitional zone between the two. The ore-hosting horizons show specific associa-tions of rocks and often contain ore beds basically of stratabound nature. 相似文献
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The deposit under study is a hydrothermal filling-metasomatic vein type lead-zinc-silver deposit, in whichgold and silver can be recovered as by-products. These metals mainly occur as microgranular native gold,electrum, stephanite, acanthite, pyraragyrite, freibergite, and native silver. Gold minerals tend to be associatedwith galenobismutite, native bismuth and unnamed Bi_2Te. They are either enclosed in pyrite, marmatite,iron-bearing sphalerite and galens or fill the microfissures of these minerals. Silver minerals usually occur incleavages or fissures of galena, marmatite and pyrite, but are not associated with gold and bismuth minerals.Gold and silver mineralizations occurred later than lead and zinc, while the silver mineralization was precededby that of gold. 相似文献
12.
The spectral reflectance features of rocks and minerals are correlated with their composition,col-or,grain size and surface state.Different wall rocks,altered rocks and ores have their spectral reflectance features,which are very helpful for the explanation of remote sensing data and searching for mineral deposits by remote sensing.After the treatment of spectrum data and searching for mineral deposits by remote sensing.After the treatment of spectrum data of rocks and ores and physical and chemical parameters in the mathematical statistics,we analyzed the laboratorial spectrum dataand put forward better wave bands(520-590,650-710,730-760,770-860,1560-1760,2200 and 2300-2400nm) for distinguishing rocks and ores. 相似文献
13.
Wang Zhiping 《《地质学报》英文版》1989,63(2):103-114
China is rich in Middle and Carboniferous fossil corals. The coral faunas in different regions have varying characteristics and can be divided into distinct assemblages. The coral fauna in South China is dominated by the order Caninida and contains numerous endemic elements; that in North China has a lot of Middle Carboniferous corals which are monotonous in species, with Late Carboniferous solitary corals being predominant. The coral fauna in Junggar mainly contains large bi-zoned solitary caninids, while that in southern Khingan is similar to that in South China due to the presence of abundant tri-zoned compound corals. In northern Tibet the coral fauna is also similar to that in South China, but in southern Tibet it is of a cold-water type. Therefore, the Middle and Late Carboniferous coral geography of China can be divided into the Tethys, Boreal and Gondwana Realms. 相似文献
14.
A. G. Bulakh 《Geology of Ore Deposits》2010,52(8):791-799
This paper reviews the history of the foundation of the Commission on New Minerals in Russia (1956) and the same Commission
of the International Mineral Association (IMA). The terms mineral species, subspecies, and variety are considered. The nomenclature
of mineral groups of lovozerite, eudialyte, and apatite is given as examples of using a root name and its suffixes. 相似文献
15.
YU Zuxiang Institute of Geology Chinese Academy of Geological Sciences Beijing Fei Zhenbi 《《地质学报》英文版》2001,75(4):458-466
In 1974 the author preliminarily reported two new platinum group minerals-daomanite and hongshiite. The two minerals were accepted by the Commission on New Minerals and Minerals Names of the International Mineralogical Association in 1976 and 1982 respectively. Because of the conditions at that time, the work was preliminary, for example, there were only reflectance values of four wave bands. Recently the author again made measurements of reflectances, corrected cell parameters by the four-circle diffractometer and electron diffraction and supplemented their new occurrences and nomenclature. 相似文献
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Mengkui TIAN Wenfeng SHANGGUAN Shijie WANG Ziyuan OUYANG 《中国地球化学学报》2006,25(B08):121-122
From primitive wood to nowadays fossil fuels such as coal, oil and natural gas, it can be seen that the forms of energy becomes more and more diverse and the core trend of decarburization is also obvious （the rate of the element of H to C ranging from 1/10, 1/2-1, 2, to 4 in wood, coal, oil and natural gas, respectively）. Although the content of C in current main fuels becomes less and less, the excess exploitation and extensive utilization of various fossil fuels are widely recognized to be responsible for the deterioration of the environment （greenhouse effect, acid rain, photochemical pollution, etc.）. With the roar consumption of energy to maintain the development of human society and taking the environmental problems into consideration, it is inevitable to develop renewable energy containing more H and less C as possible. Under these circumstances, the development of H2 energy is the certain and ultimate choice for its high energy per unit, diversity resources, no pollution to environment and ideal renewable utilization cycle. There are so many methods and ways were employed to develop HE energy, such as electrolysis, methane stream reforming process, coal gasification, etc., but there lies two main problems in current methods and ways, those are the cost of bulk of first energy to extract HE from fossil raw materials and still facing the problems of C deposition （carbon dioxide）. Consequently, if considering the cost and environmental issues, the development of HE energy must resort to renewable energy sources such as solar energy, wind energy to extract HE from water. Based on this context, the development of HE energy by semiconductor photocatalyst to split water into HE and O2 under the irradiation of solar energy, photocatalysis process in short word, is one of the most promising ways. In this review, the importance and necessity to develop hydrogen energy were intensively studied based on the relationship between energy consumption and environment effect. Then the current ways and methods to develop hydrogen were reviewed, especially the state-of-the-art photocatalysis process （from the semiconductor photocatalyst materials perspective）. 相似文献
18.
Past and Future of Mathematical Geology 总被引：1，自引：0，他引：1
FrederikPAgterberg 《中国地质大学学报(英文版)》2003,14(3):191-198
This is a brief review of alternative methods of problem-solving in geoscience with emphasis on the role of mathematical geology. It is desirable to maintain a clear-cut distinction between reliable facts which can be stored in data banks and concepts that can be incorporated in the speciflcations of sta-tistical models designed for specific purposes. If possible, subjective probabilities shclld be incorporated in hypotheses that are to be tested by statistical inference. 相似文献
19.
《中国地球化学学报》2006,(Z1)
Effects of EDTA and heavy metals on growth of Typha latifolia and its uptake and translocation of Pb and Cd were investigated in this study. Both Pb and Cd of high concentrations had inhibitory effect on growth of Typha latifolia. Chlorophyll concentratio… 相似文献
20.
On the basis of an experimental study and thermodynamic calculation, the mechanisms of paragenesis and separation of silver, lead and zinc in the hydrothermal system have been studied. At acidic to nearly neutral pH, their chloride complexes are stable, and among them the chloride complexes of zinc are most stable. And the sulfide complexes are the dominant species at nearly neutral to alkaline pH,while the sulfide complexes of silver are most stable. With decreasing temperature, [ Cl^-] ,fO2, and increasing pH, the solubilities of silver, lead and zinc will decrease, leading to their deposition and separation. For sulfide complexes, the concentrations of reduced sulfur and pH are two important factors affecting their stabilities. Complexes of different forms and stabilities respond to the variation of conditions to different extents, which gave rise to the paragenesis and separation of silver, lead and zinc in the whole ore-forming process of dissolution, transport and deposition. 相似文献