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The sorption of aqueous cadmium on carbonate-hydroxyapatite (CHap) is a complicated non-homogeneous solid/water reaction, From kinetic point of view, it can be described by two stages: at the earlier stage, reaction rate is so fast that its kinetic course is intricate, and at the later stage, the rate of reaction becomes slow and the process of reaction accords with one order reaction kinetic equation. Experimental results show that the relationship between reaction rate constant kl and temperature T accords to Arrhenius Equation, and the activation energy of sorption (Ea) is 6.075 J/mol and frequency factor (A) is 220 s^-1. At the same time, reaction rate constant kl increases with decreasing Cd^2+ initial concentration, on the contrary, with increasing pH and CHap dosage.  相似文献   

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lNTRODUCTlONBase iso1ation is regarded as a practical and economicalway to protect structures from damages subjected to earth-quake motion. Isolators implemented between the base raft ofthe structure and foundation can dissipate and absorb earth-quake energy, and reduce obviously the transmission of groundmotion to structure. In short, the principle of base isolation in-cludes two factors: (i) The natural period of structures withfixed base is usually 0. 2-- l. 2 s, close to the natural pe…  相似文献   

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As located in the junction of three tectonic plates (the Eurasian plate, the Indian plate and the west Pacific plate), the China continent shows complex regional metallogenic features due to tectonic evolution of “micro-plates, polycycle tectonic movements”. Well developed superimposed metailogenic systems have constituted one of the regional metallogenic features in China. Through the study on superimposed metailogenic system of the middle and lower reaches of the Yangtze River and of the Yuebei basin (northern Guangdong Province), the authors put forward some basic combination pattern of sedimentary-magmatic superimposed metailogenic system and summarize its forming conditions (controlling factors).  相似文献   

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Geotechnical and Geological Engineering - The solidification technology of sludge can effectively solve the problem of environmental pollution and resource shortage. Whereas, the current study...  相似文献   

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Please refer to the attachment(s) for more details  相似文献   

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A new type of vortex structure-binucleus-type vortex structure-is presented in this paper. It is charac-terized by two nuclear columns which distinguish it from uninuclcus-type vorlex structure. The vortical sur-faces of the structure are commonly s-shaped and reversed s-shaped and subordinately of clliptic andhyperbolic shape. and sometimes turbine-like surfaces are observed. On the basis of field structural studies. a mechanical model of rotation around a binuclear column ofcrustal materials is presented in the paper. Burgers viscoelastic solutions of the stress field and deformationfield of this structural type have been obtained using the principle and method of rheology. and simulation ex-periments have been performed. The results of the theoretical calculation and experiments indicate that theproposed mechanical model is applicable.  相似文献   

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Toluene diisocyanate (TDI) is an important industrial raw material that is widely used in manufacture of polyurethane coating and insulating materials. TDI is universally considered to be an industrial allergen, which can be introduced into human bodies b…  相似文献   

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Please?refer?to?the?attachment(s)?for?more?details.  相似文献   

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INTRODUCTIONRock deformation is normally explained by tec-tonic stress as rock deformation results fromthe tec-tonic stress field. The classic tools that explainedfracture mechanisms were the Coulomb shear fracturerule and the Anderson mode derived fromit (Zhu,1999) . More and more studies have shown that it isdifficult to explain rock deformation in a large strainrange using only the Coulomb shear fracture rule( Waltham,2002 ; Gutscher et al .,2001 ; Tikoff andWojtal ,1999) . As a ver…  相似文献   

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The Kunyang Aulacogen is a continental rift which initiated at the beginning of the Middle Proterozoic. Itwas generated on the rigid continental crust represented by the crystalline Kangding Complex, and is boundedby two N-S-trending deep faults--Anninghe-Luzhijiang Fault and Xiaojiang Fault. Its early stage of rupturewas characterized by alkalinc mafic igneous activities in the Dahongshan Group and Hekou Group. Duringthe later tensile-depression stage the aulacogen evolved into a graben where scdimentation of the KunyangGroup took place. The sedimentary sequence comprises terrestrial red beds, algal dolomite, marine black shaleand carbonate rocks which are quite typical of rift sedimentary association, and contains stratabound copperdeposits of the well-known Dongchuan type.  相似文献   

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The load distribution and deflection of large diameter piles are investigated by lateral load transfer method (py curve). Special attention is given to the soil continuity and soil resistance using three-dimensional finite element analysis. A framework for determining a py curve is calculated based on the surrounding soil stress. The appropriate parametric studies needed for verifying the py characteristic are presented in this paper. Through comparisons with results of field load tests, the three-dimensional numerical methodology in the present study is in good agreement with the general trend observed by in situ measurements and thus, represents a realistic soil–pile interaction for laterally loaded piles in clay than that of existing py method. It can be said that a rigorous numerical analysis can overcome the limitations of existing py methods to some extent by considering the effect of realistic three-dimensional combination of pile–soil forces.  相似文献   

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The different aspects lead to great differences in the processes of water,heat,and energy balance,which further affect the soil environment and the growth of alpine plants. Based on an experimental study with eight aspects(abbreviated as octagonal platform)of Huashixia frozen soil observation base on the Qinghai-Tibet Plateau,the influence of aspects on soil environments and alpine vegetation growth was studied. The results showed that:(1)After 6 years,the soil temperature of each slope near the surface(10 cm and 30 cm depth)from high to low was as follows:south > southeast > southwest > west > east > northwest > northeast > north,that is,the relatively sunny slope(east,southeast,south and southwest)was higher than the relatively shady slope(west,northwest,north and northeast). However,there was no significant difference in soil water con⁃ tent between the sunny slope and the shady slope at the depth of 0~30 cm. (2)The growth trend of aboveground vegetation(including plant height,coverage and aboveground biomass)on sunny slope was better than that on shady slope. The growth trend of underground vegetation(including root depth and underground biomass)on sunny slope was worse than that on shady slope. (3)In the depth of 0~10 cm,the content of soil organic carbon and total nitrogen on sunny slope was higher than that on shady slope. However,the content of total phosphorus on sunny slope was lower than that on shady slope. There was no significant difference in total potassium and available nutrients among different slopes(P>0. 05). In general,the effect of temperature on vegetation growth and nutrient distribution is significant in alpine regions,and these findings provides an important reference for vegetation restoration and energy balance research in different aspects. © 2023 The Author(s).  相似文献   

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1 Introduction Because clay minerals have the characteristics ofadsorption, ion exchange capability and expandingcapacity, they are highly capable of adsorbing allkinds of pollutants in waters, thus making soilspossess self-purification functions. Clay m…  相似文献   

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Based on state-space method and component analysis, this paper builds a comprehensive evaluation system of carrying capacity for the Beijing–Tianjin–Hebei region from four aspects, namely economy, environment, ecology and energy. The results show that the comprehensive carrying capacity in this region gradually rises in recent years and the economic carrying capacity plays an important role in this situation. Ecological and environmental carrying capacity are gradually enhanced but still affected by water shortages. The energy carrying capacity of this region is low, which is the major factor restricting its sustainable development. Based on the empirical results, following policy suggestions should be adopted: Firstly, local government should accelerate technological progress, promoting the optimization and upgrading of industrial structure; Secondly, the contradiction between supply and demand of water resource should be solved gradually; thirdly, government should develop recycling economy, realizing the coordinated development of economy and environment; last but not least, saving energy and improving energy efficiency.  相似文献   

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AsesmentonCrustalStabilityUsingFuzzyMathematicsinDamRegionofThreeGorgesProjectonYangtzeRiver*TanChengxuanHuDaogongInstituteof...  相似文献   

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Yang Zuosheng 《GeoJournal》1995,37(1):186-189

The International Geographical Union Reports

IGU Commission on Marine Geography — CMG  相似文献   

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