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Characteristics of Phosphorous Adsorption and Desorption by Organo-Mineral Colloidal Complexes of Purple Paddy Soils 被引量:2
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作者 GAOMING ZHOUBAOTONG 《Pedosphere》 SCIE CAS CSCD 2002年第3期257-264,共8页
The kinetic characteristics of P adsorption and desorption by organo-mineral colloidal complexes (OMC)were studied using acid, calcareous and neutral purple paddy soils taken from Chongqing and Sichuan, China.The resu... The kinetic characteristics of P adsorption and desorption by organo-mineral colloidal complexes (OMC)were studied using acid, calcareous and neutral purple paddy soils taken from Chongqing and Sichuan, China.The results showed that the P adsorption capacity of the organo-mineral colloidal complexes differed with the soil types, being higher for the acid and calcareous purple soils than for the neutral purple soils. Partial removal of the organic matter increased the adsorption capacity of the colloidal complexes. A very significant positive correlation was found between the amounts of P desorbed from OMC and the P saturation degrees.The P adsorption reaction was quick at the early stage and slowed later. The raise of temperature increased P adsorption capacity and P adsorption rate of the colloidal complexes. The adsorption processes could be described by the Elovich equation. 展开更多
关键词 adsorption DESORPTION organo-mineral colloidal complex phosphorus purplepaddy soils
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Composition and Characteristics of Organo-Mineral Complexes of Red Soils in South China
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作者 XUJIAN-MING HOUHUI-ZHEN 《Pedosphere》 SCIE CAS CSCD 1992年第1期23-30,共8页
The objective of the present study is to reveal the composition and characteristics of organo-mineral complexes in red soils (red soil, lateritic red soil and latosol) of south China in terms of chemical dissolution a... The objective of the present study is to reveal the composition and characteristics of organo-mineral complexes in red soils (red soil, lateritic red soil and latosol) of south China in terms of chemical dissolution and fractional peptization methods. In the combined humus, most of the extractable humus could dissolve in 0.1 M NaOH extractant and belonged to active humus (H1), and there was only a small amount of humus which could be further dissolved in 0.1 M Na4P2O7 extractant at pH 13 and was stably combined humus (H2). The H1/ H2 ratio ranged from 3.3 to 33.8 in red soils, and the proportions of both H, and total extractable organic carbon (H1+H2) in total soil organic carbon and the ratios of H1 to H2 and H1 to (H1 +H2) were all higher in lateritic red soil and latosol than in red soil. The. differences of combined humus composition in various red soils were directly related to the content of Fe and Al oxides. In organo-mineral complexes, the ratio of Na-dispersed fraction (G1) to Na-ground-dispersed fraction (G2) was generally smaller than 1 for red soils, but there was a higher G1 / G2 ratio in red soil than in lateritic red soil and latosol. G1 fraction had a higher content of fulvic acid (FA), but G2 fraction had a higher content of humic acid (HA). The ratios of H1 to H2 and HA to FA were higher in G2 than in G1. The differences in the composition and activity of humus between G1 and G2 fractions were related to the content of free Fe and Al oxides. The quantities of complex Fe and Al, the Fe/ C and Al/ C atomic ratios were higher in G2 than in G1, and the ratio of Al/ C was much higher than that of Fe/ C. It may be deduced that aluminum plays a more important role than iron in the formation process of organo-mineral complexes in red soils. 展开更多
关键词 combined humus organo-mineral complexes OXIDES red soils
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Characteristics of Organo-Mineral Complexing of Microaggregates in Paddy Soils Developed from Purple Soils 被引量:1
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作者 WEICHAOFU XIEDETI 《Pedosphere》 SCIE CAS CSCD 1996年第4期365-372,共8页
This paper deals with characteristics of organo-mineral complexing of microaggregates in the paddy soils developed from purple soils in Sichuan, China. Results show that the contents of organic matter in microaggregat... This paper deals with characteristics of organo-mineral complexing of microaggregates in the paddy soils developed from purple soils in Sichuan, China. Results show that the contents of organic matter in microaggregates are in the order of 1--0.25 mm > smaller than 0.05 mm > 0.05-0.25 mm. But the organic matter in 1-0.01 mm microaggregates accounts for 68.1%-78.7% of that in soil. The organic matter in<0.05 mm microaggregates is complexed humus on the whole, of which the degree of organo-mineral complexing varies between 96.1% and 99.5%, which is higher than that of the soil or>0.05 mm microaggregates. The contents of loosely combined humus and the ratios of loosely and tightly combined humus markedly decline with the size of microaggregates. Fresh soil humus formed from semi-decomposed organic material or organic manure added is combined first with<0.001 mm clay, and then aggregated with other organic and mineral particles to form larger microaggregates, in which the aging of humus happens at the same time; whereas organic matter of the light fraction is mainly involved in the formation of>0.05 mm microaggregates. 展开更多
关键词 combined humus microaggregate organo-mineral complexing paddy soils from purple soils
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Effects of complexing agents on acidic electroless nickel deposition 被引量:6
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作者 JIN Ying YU Hongying +1 位作者 YANG Dejun SUN Dongbai 《Rare Metals》 SCIE EI CAS CSCD 2010年第4期401-406,共6页
Our previous study reported the influences of different complexing agents on electroless nickel (EN) by examining the properties of the deposits. In the present work, the effects of four common-used complexing agent... Our previous study reported the influences of different complexing agents on electroless nickel (EN) by examining the properties of the deposits. In the present work, the effects of four common-used complexing agents on EN deposition rate and the stability of solution pH values were examined, either with an acetic pH buffer agent or absent of them. It is indicated that the pH buffeting effect of them is dominative when the EN solution is lack of the pH buffer. Under this situation, the EN deposition rate increases with the concentration of complexing agents increasing. The EN deposition rate decreases with fin'ther adding the complexing agent when the solution already has enough pH buffer capability. Electrochemical impedance spectroscopy obtained during EN deposition illustrates that, in this case, the enhanced reaction resistance is the main reason for a lower deposition rate. However, the influence of polarization caused by mass transfer is not negligible at high complex ratio for sodium citrate and malic acid EN solutions. 展开更多
关键词 electroless nickel complexing agents electrochemical impedance spectrum reaction resistance pH value
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Positively charged nanofiltration membrane fabricated by poly(acid–base) complexing effect induced phase inversion method for heavy metal removal 被引量:1
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作者 Chunli Liu Weihui Bi +2 位作者 Dongliang Chen Suobo Zhang Hongchao Mao 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2017年第11期1685-1694,共10页
Poly(arylene ether ketone)s with carboxylic groups(PAEK-COOH)is a good membrane fabrication material,a kind of polyacids,while polyethylenimine(PEI)is a weak organic base,a kind of polybases.Those polyacids and polyba... Poly(arylene ether ketone)s with carboxylic groups(PAEK-COOH)is a good membrane fabrication material,a kind of polyacids,while polyethylenimine(PEI)is a weak organic base,a kind of polybases.Those polyacids and polybases would form ionic complexation at the interface of two liquid phases.In this paper,PAEK-COOH/N-methyl pyrrolidone(NMP)/1,4-dioxane(DO)mixture,employed as polymer casting solution and aqueous solution of PEI,used as coagulation bath,respectively.Then ion complexation induced phase inversion process is applied to prepare positively charged nanofiltration membrane with thinner but denser separation skin layer.The complexing reaction at the interface of two liquid phases has great influence on the kinetic aspects of phase inversion process,which in accordance would affect the morphology and performance of the membrane.The obtained membrane,fabricated via the ion complexation induced phase inversion method,is positively charged,has high water permeability,and possesses high rejection towards divalent cations,such as Mg^(2+),Ca^(2+),Pb^(2+)etc.,which could be used for removal of heavy metals from polluted water.At the optimal condition,the pure water flux of the PAEK-COOH-PEI nanofiltration membrane is 24.3 L·m^(-2)·h^(-1),with MgCl_2rejection of 92.2%. 展开更多
关键词 POLYELECTROLYTE complex Carboxylated polymer POLYETHYLENIMINE NANOFILTRATION Water PURIFICATION
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Syntheses,Crystal Structures and Complexing Properties of 1,3-Distal Calix[4]arene Schiff Bases 被引量:1
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作者 LI Liang GU Wei-wei YAN Chao-guo 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2010年第1期38-45,共8页
Novel 1,3-distal p-tert-butylcalix[4]arene Schiff bases were efficiently synthesized in three steps. At first p-tert-hutylcalix[4]arene was reacted with N-2-hydroxyethylphthalimide catalyzed by TPP/DEAD or alkylated w... Novel 1,3-distal p-tert-butylcalix[4]arene Schiff bases were efficiently synthesized in three steps. At first p-tert-hutylcalix[4]arene was reacted with N-2-hydroxyethylphthalimide catalyzed by TPP/DEAD or alkylated with ω-hatoalkylphthalimide in the system of K2CO3/KI/CH3COCH3 to give 1,3-distal diphthalimidoalkyl calixarenes, which were in turn hydrazinolyzed to give diaminoalkyl calixarenes. Then with the aid of the condensation of active calixarene amines with salicylaldehyde, 2-hydroxy-l-naphthaldehyde or pyridine-2-carboxaldehyde, a series of 1,3-distal calixarene Schiff bases was prepared in satisfied yields. The single crystal structures and complexing properties of these Schiff bases for transition metal ions were studied. 展开更多
关键词 CALIXARENE Schiffbase Crystal structure Metal complex UV spectroscopy
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Structure and Shape Control of Hydrothermally Synthesized PbTiO_3 --Effects of pH and Complexing Agents 被引量:1
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作者 XIAO Li-hua +2 位作者 CHEN Dai-rong 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2003年第1期1-5,共5页
Tabular PE PbTiO 3, spherical PY PbTiO 3, and acicular PX PbTiO 3 powders were hydrothermally synthesized from triethanolamine(TEA) complexed precursor; clubbed PE PbTiO 3 powders were obtained from diethanol... Tabular PE PbTiO 3, spherical PY PbTiO 3, and acicular PX PbTiO 3 powders were hydrothermally synthesized from triethanolamine(TEA) complexed precursor; clubbed PE PbTiO 3 powders were obtained from diethanolamine(DEA) complexed precursor. The effects of pH of the hydrolyzation as well as complexing agents including TEA, DEA, and MEA(monoethanolamine) on the structure and the morphology of PbTiO 3 powders are discussed. The optimal conditions for hydrothermal syntheses of acicular and clubbed PbTiO 3 powders have been established. The products were characterized by means of XRD, TEM and other techniques. 展开更多
关键词 Lead titanate Hydrothermal synthesis complexing agent
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Studies on the Synthesis and Complexing Behavior of Crown Ethers with External Coordination Center 被引量:1
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作者 Jing Chao TAO Yang Jie WU* +1 位作者 Shang Jie XU Da Peng ZOU 《Chinese Chemical Letters》 SCIE CAS CSCD 2001年第6期479-482,共4页
The synthesis, characterization of five ditopic or tritopic crown compounds were reported in this paper together with the preparation of the corresponding hetero-dinuclear and hetero-trinuclear complexes with differen... The synthesis, characterization of five ditopic or tritopic crown compounds were reported in this paper together with the preparation of the corresponding hetero-dinuclear and hetero-trinuclear complexes with different metal cations. 展开更多
关键词 Polytopic crown ether hetero-polynuclear complex CO-ORDINATION
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The Effect of Organo-Mineral Fertilizer Applications on the Yield of Winter Wheat, Spring Barley, Forage Maize and Grass Cut for Silage 被引量:3
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作者 Grace H. Smith Keith Chaney +1 位作者 Charles Murray Minh Son Le 《Journal of Environmental Protection》 2015年第2期103-109,共7页
Biosolids were applied with urea to produce a granulated organo-mineral fertiliser (OMF) for application by farm fertiliser equipment to a range of agricultural crops. The recommended rates of nitrogen, phosphate and ... Biosolids were applied with urea to produce a granulated organo-mineral fertiliser (OMF) for application by farm fertiliser equipment to a range of agricultural crops. The recommended rates of nitrogen, phosphate and potash were calculated for the test crops using “The Fertiliser Manual”, which assesses the nutrient requirement based on previous cropping, rainfall and soil index. The OMF produced similar crop yields compared to ammonium nitrate fertiliser when applied as a top-dressing to winter wheat, forage maize and grass cut for silage in the cropping years 2010 to 2014. In 2012 the grain yield of spring barley top-dressed with OMF was significantly lower than the conventional fertiliser treatment, due to dry conditions following application. For this reason it is recommended that OMF is incorporated into the seedbed for spring sown crops and The Safe Sludge Matrix guidelines followed. The experimental work presented shows that OMF can be used in sustainable crop production systems as a source of nitrogen and phosphorus for a range of agricultural crops. 展开更多
关键词 BIOSOLIDS organo-mineral FERTILISER Crop YIELD Winter Wheat Spring BARLEY Forage Maize GRASS SILAGE
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Facile synthesis of La_2Mo_2O_9 nanoparticles via an EDTA complexing approach 被引量:1
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作者 CHENG Hua WANG Hongen +2 位作者 LI Liang LU Zhouguang QIAN Dong 《Rare Metals》 SCIE EI CAS CSCD 2008年第4期340-344,共5页
A facile EDTA (ethylene diamine tetraacetic acid) complexing technique has been successfully employed to prepare La2Mo2O9 nanoparticles. The as-synthesized products are characterized by X-ray diffraction (XRD), sc... A facile EDTA (ethylene diamine tetraacetic acid) complexing technique has been successfully employed to prepare La2Mo2O9 nanoparticles. The as-synthesized products are characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and Fourier transform infrared spectroscopy (FT-IR). The results show that a homogeneous transparent gel can be obtained with EDTA as the organic complexing reagent under the pH value of 3.0. Further thermal decomposition of the as-synthesized transparent gel by increasing the temperature up to 600℃ for 3 h results in the formation of La2Mo2O9 nanoparticles with a crystal size of about 30 nm. Moreover, the nanoparticles tend to form micrometer-sized aggregates with a three-dimensional network structure, which shows promising applications in solid oxide fuel cells (SOFC), catalysts and so on. 展开更多
关键词 inorganic non-metal materials EDTA complexing SOL-GEL La2Mo2O9 NANOPARTICLES porous structure
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Synthesis and Complexing Properties of Three Aminopolyphosphonic Acids with Rare Earth Ions
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作者 高锦章 赵国虎 +2 位作者 韩小茜 康敬万 王荣 《Rare Metals》 SCIE EI CAS CSCD 1999年第4期254-263,共10页
Three white crystalline aminopolyphosphonic acids, DTHMP, TTHMP and TPHMP were synthesized by a modified Mannich reaction under gentle conditions. The products were isolated and purified with a SP-Sephadex C-25 column... Three white crystalline aminopolyphosphonic acids, DTHMP, TTHMP and TPHMP were synthesized by a modified Mannich reaction under gentle conditions. The products were isolated and purified with a SP-Sephadex C-25 column. The acid-base and complexing properties of three aminopolyphosphonic acids with rare earth ions were investigated by means of potentiometric titration in aqueous medium at (25 +/- 0.1) degrees C and ionic strength I = 0.1 mol/L KNO3. The successive protonation constants of ligands and the formation constants of complexes with rare earth elements were obtained. The results show a double-double effect for lgK(MHiL) against atomic number of lanthanide. The properties are advantageous for the separation of the rare earth elements. 展开更多
关键词 rare earth elements aminopolyphosphonic acid complexing properties
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Study on copper complexing ligand concentrations in several China's coastal waters
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作者 GONG Haidong ZHANG Zhengbin LIU Chunying LIU Liansheng 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2006年第1期64-77,共14页
Copper complexing ligand concentrations in the Daya Bay, Qingdao coast, Jiaozhou Bay, South China Sea and Huanghe Estuary waters were determined by the anodic stripping voltammetry technique. The distribution regulari... Copper complexing ligand concentrations in the Daya Bay, Qingdao coast, Jiaozhou Bay, South China Sea and Huanghe Estuary waters were determined by the anodic stripping voltammetry technique. The distribution regularity and the relationship with other parameters were discussed. The results were as follows: Copper complexing ligand concentrations of the South China Sea were a little higher than those of other sea areas, and they were apparently higher than those of the ocean. Compared with the subsurface layer (SSL) in the sea surface microlayer copper complexing ligand concentrations showed an enrichment phenomenon, of which the mechanism is similar to dissolved organic matter. The metal complexing ligand concentration profiles of the South China Sea showed that the value in the sea surface was the highest, then it decreased with depth accruing, and a higher value appeared at the bottom. Copper complex- ing ligand concentrations were higher than those of cadmium and lead. Ligands in each sea area exhibited a complicated property. In short, the distribution regularity of copper complexing ligand concentrations in China's coastal waters was consistent with that of other regions in the world. Meanwhile, the positive relationship between the copper complexing ligand concentrations and biological oxygen demand, chemical oxygen demand, dissolved organic carbon, and viscosity were found clearly. 展开更多
关键词 copper complexing ligand concentrations China' s coastal waters distribution regularity RELATIONSHIP
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Complexing Properties of Acid Alizarin Violet with Copper, Cobalt and Nickel in Micellar Media Containing SDS, CTAB and TX-100
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作者 Fawwaz Jumean Magdy El-Dakiky +3 位作者 Adnan Manassra Manal Abdul Kareem Mohammad Abu Alhaj Mustafa Khamis 《American Journal of Analytical Chemistry》 2014年第1期1-7,共7页
The interaction of the dye acid alizarin violet (AVN) with three transition metals was followed spectrophotometrically in water and in micellar solutions of the cationic cetyltrimethylammonium bromide (CTAB), the anio... The interaction of the dye acid alizarin violet (AVN) with three transition metals was followed spectrophotometrically in water and in micellar solutions of the cationic cetyltrimethylammonium bromide (CTAB), the anionic sodium dode- cyl sulfate (SDS) and the nonionic triton X-100 (TX-100). The stoichiometric ratios for the complexes of AVN with each metal ion were determined by the mole ratio and the continuous variation methods. In water, the metal to dye ratios in the complexes were 1:2, 1:3 and 1:1 for Cu2+, Co2+ and Ni2+, respectively. For Ni2+ the ratio changed to 1:3 in micellar CTAB. All other ratios were unchanged in the three micellar solutions. The formation constant (βn) of the complex in water was 1.00 × 1010 for Cu2+, 4.66 × 1014 for Co2+ and 9.03 × 104 for Ni2+. βn decreased in micellar TX-100: for Cu2+ to 6.88 × 108, for Co2+ to 1.56 × 1014 and for Ni2+ to 8.65 × 104. By contrast, micellar CTAB increased βn for Cu2+ and Ni2+. For Cu2+, the increase was to 5.19 × 1010, but for Ni2+ a large jump was observed, to 1.16 × 1015. For Co2+, βn dropped to 2.16 × 1014 in CTAB. Micellar SDS decreased βn for Cu2+ and Co2+ complexes to 5.38 × 109 and 1.76 × 1014, respectively, but increased that of the Ni2+ complex to 4.40 × 105. These observations were explained in terms of structural properties. 展开更多
关键词 complexATION AVN MICELLIZATION
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Agglomerate control in the complexing sol-gel process
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作者 尹邦跃 王零森 +1 位作者 樊毅 张金生 《中国有色金属学会会刊:英文版》 EI CSCD 1999年第4期712-716,共5页
Nanometer ZrO2 - 8% Y2O3 (mole fraction, % ) powders were prepared by the EDTA (ethylenediaminetetraacetic acid) sol-gel process. Effects of the addition of ethylene glycol on agglomerate control was investigated. The... Nanometer ZrO2 - 8% Y2O3 (mole fraction, % ) powders were prepared by the EDTA (ethylenediaminetetraacetic acid) sol-gel process. Effects of the addition of ethylene glycol on agglomerate control was investigated. The results showed that because of the replacement of hydrogen bonds with ethylene glycol in the polymerized gel, gel stabilization and homogeneity were improved and close approach of gel particles was prevented, which led to reduction of hard agglomerates to some extent. Calcined at 4OO t for 2 h and 700 C for 2 h, the powders had a specific surface area of 35 m2/g, average particle size of 28 nm, and median particle size (d50) of 0. 44um with very sharp distribution, mostly being soft agglomerates. 展开更多
关键词 complexing EDTA SOL-GEL process ZrO2 (Y2O3) AGGLOMERATION
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The Effect of Improving soil Fertility on Status of Organo-mineral Complexing in Chestnut soils
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作者 Liu Shuqing Huo Xiliang(Agricultural University of Hebei,Baoding 071001) 《河北农业大学学报》 CAS CSCD 北大核心 1995年第S1期41-46,共6页
TheEffectofImprovingsoilFertilityonStatusofOrgano-mineralComplexinginChestnutsoils¥LiuShuqing;HuoXiliang(Agr... TheEffectofImprovingsoilFertilityonStatusofOrgano-mineralComplexinginChestnutsoils¥LiuShuqing;HuoXiliang(AgriculturalUniversi... 展开更多
关键词 CHESTNUT complexing
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Modeling time-dependent mechanical behavior of hard rock considering excavation-induced damage and complex 3D stress states 被引量:1
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作者 Peiyang Yu Xiuli Ding +3 位作者 Peng-Zhi Pan Shuting Miao Zhaofeng Wang Shuling Huang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第10期4046-4065,共20页
To investigate the long-term stability of deep rocks,a three-dimensional(3D)time-dependent model that accounts for excavation-induced damage and complex stress state is developed.This model comprises three main compon... To investigate the long-term stability of deep rocks,a three-dimensional(3D)time-dependent model that accounts for excavation-induced damage and complex stress state is developed.This model comprises three main components:a 3D viscoplastic isotropic constitutive relation that considers excavation damage and complex stress state,a quantitative relationship between critical irreversible deformation and complex stress state,and evolution characteristics of strength parameters.The proposed model is implemented in a self-developed numerical code,i.e.CASRock.The reliability of the model is validated through experiments.It is indicated that the time-dependent fracturing potential index(xTFPI)at a given time during the attenuation creep stage shows a negative correlation with the extent of excavationinduced damage.The time-dependent fracturing process of rock demonstrates a distinct interval effect of the intermediate principal stress,thereby highlighting the 3D stress-dependent characteristic of the model.Finally,the influence of excavation-induced damage and intermediate principal stress on the time-dependent fracturing characteristics of the surrounding rocks around the tunnel is discussed. 展开更多
关键词 Hard rock Excavation damage complex stress state Three-dimensional(3D)time-dependent model
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Saturation Estimation with Complex Electrical Conductivity for Hydrate-Bearing Clayey Sediments:An Experimental Study 被引量:1
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作者 XING Lanchang ZHANG Shuli +8 位作者 ZHANG Huanhuan WU Chenyutong WANG Bin LAO Liyun WEI Wei HAN Weifeng WEI Zhoutuo GE Xinmin DENG Shaogui 《Journal of Ocean University of China》 CAS CSCD 2024年第1期173-189,共17页
Clays have considerable influence on the electrical properties of hydrate-bearing sediments.It is desirable to understand the electrical properties of hydrate-bearing clayey sediments and to build hydrate saturation(S... Clays have considerable influence on the electrical properties of hydrate-bearing sediments.It is desirable to understand the electrical properties of hydrate-bearing clayey sediments and to build hydrate saturation(S_(h))models for reservoir evaluation and monitoring.The electrical properties of tetrahydrofuran-hydrate-bearing sediments with montmorillonite are characterized by complex conductivity at frequencies from 0.01 Hz to 1 kHz.The effects of clay and Sh on the complex conductivity were analyzed.A decrease and increase in electrical conductance result from the clay-swelling-induced blockage and ion migration in the electrical double layer(EDL),respectively.The quadrature conductivity increases with the clay content up to 10%because of the increased surface site density of counterions in EDL.Both the in-phase conductivity and quadrature conductivity decrease consistently with increasing Sh from 0.50 to 0.90.Three sets of models for Sh evaluation were developed.The model based on the Simandoux equation outperforms Archie’s formula,with a root-mean-square error(E_(RMS))of 1.8%and 3.9%,respectively,highlighting the clay effects on the in-phase conductivity.The fre-quency effect correlations based on in-phase and quadrature conductivities exhibit inferior performance(E_(RMS)=11.6%and 13.2%,re-spectively)due to the challenge of choosing an appropriate pair of frequencies and intrinsic uncertainties from two measurements.The second-order Cole-Cole formula can be used to fit the complex-conductivity spectra.One pair of inverted Cole-Cole parameters,i.e.,characteristic time and chargeability,is employed to predict S_(h) with an E_(RMS) of 5.05%and 9.05%,respectively. 展开更多
关键词 gas hydrate complex electrical conductivity hydrate-bearing clayey sediment hydrate saturation Simandoux equation frequency dispersion Cole-Cole formula
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Study of the Influence of the Electrolysis Parameters on Mn-Zn, Mn-Cu and Mn-Cu-Zn Alloys Coatings from Electrolytes Containing Complexing Ligands
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作者 Gigla Tsurtsumia Nana Koiava +4 位作者 David Gogoli Izolda Kakhniashvili Tinatin Lejava Nunu Jokhadze Ermi Kemoklidze 《Journal of Chemistry and Chemical Engineering》 2016年第1期13-27,共15页
The process of obtaining of high quality Mn-Zn, Mn-Cu and Mn-Cu-Zn alloy coatings from complexing ligands--citrate, EDTA (ethylene diaminetetra acetic acid) and nitrilotriacetic acid solutions was studied. Factors a... The process of obtaining of high quality Mn-Zn, Mn-Cu and Mn-Cu-Zn alloy coatings from complexing ligands--citrate, EDTA (ethylene diaminetetra acetic acid) and nitrilotriacetic acid solutions was studied. Factors affecting stability of solutions containing ligand or ligands and influence of electrolysis parameters: electrolyte composition, pH, cathodic current density on chemical composition of the obtained coatings, on their current efficiency, morphology and structure were investigated. 展开更多
关键词 MN-ZN Mn-Cu Mn-Cu-Zn electrodeposition complexing ligands chemical composition current density current efficiency SEM XRD.
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A novel complex-high-order graph convolutional network paradigm:ChyGCN
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作者 郑和翔 苗书宇 顾长贵 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期665-672,共8页
In recent years,there has been a growing interest in graph convolutional networks(GCN).However,existing GCN and variants are predominantly based on simple graph or hypergraph structures,which restricts their ability t... In recent years,there has been a growing interest in graph convolutional networks(GCN).However,existing GCN and variants are predominantly based on simple graph or hypergraph structures,which restricts their ability to handle complex data correlations in practical applications.These limitations stem from the difficulty in establishing multiple hierarchies and acquiring adaptive weights for each of them.To address this issue,this paper introduces the latest concept of complex hypergraphs and constructs a versatile high-order multi-level data correlation model.This model is realized by establishing a three-tier structure of complexes-hypergraphs-vertices.Specifically,we start by establishing hyperedge clusters on a foundational network,utilizing a second-order hypergraph structure to depict potential correlations.For this second-order structure,truncation methods are used to assess and generate a three-layer composite structure.During the construction of the composite structure,an adaptive learning strategy is implemented to merge correlations across different levels.We evaluate this model on several popular datasets and compare it with recent state-of-the-art methods.The comprehensive assessment results demonstrate that the proposed model surpasses the existing methods,particularly in modeling implicit data correlations(the classification accuracy of nodes on five public datasets Cora,Citeseer,Pubmed,Github Web ML,and Facebook are 86.1±0.33,79.2±0.35,83.1±0.46,83.8±0.23,and 80.1±0.37,respectively).This indicates that our approach possesses advantages in handling datasets with implicit multi-level structures. 展开更多
关键词 raph convolutional network complex modeling complex hypergraph
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Discovery of nano organo-clay complex pore-fractures in shale and its scientific significance:A case study of Cretaceous Qingshankou Formation shale,Songliao Basin,NE China
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作者 SUN Longde WANG Fenglan +5 位作者 BAI Xuefeng FENG Zihui SHAO Hongmei ZENG Huasen GAO Bo WANG Yongchao 《Petroleum Exploration and Development》 SCIE 2024年第4期813-825,共13页
A new pore type,nano-scale organo-clay complex pore-fracture was first discovered based on argon ion polishing-field emission scanning electron microscopy,energy dispersive spectroscopy and three-dimensional reconstru... A new pore type,nano-scale organo-clay complex pore-fracture was first discovered based on argon ion polishing-field emission scanning electron microscopy,energy dispersive spectroscopy and three-dimensional reconstruction by focused ion-scanning electron in combination with analysis of TOC,R_(o)values,X-ray diffraction etc.in the Cretaceous Qingshankou Formation shale in the Songliao Basin,NE China.Such pore characteristics and evolution study show that:(1)Organo-clay complex pore-fractures are developed in the shale matrix and in the form of spongy and reticular aggregates.Different from circular or oval organic pores discovered in other shales,a single organo-clay complex pore is square,rectangular,rhombic or slaty,with the pore diameter generally less than 200 nm.(2)With thermal maturity increasing,the elements(C,Si,Al,O,Mg,Fe,etc.)in organo-clay complex change accordingly,showing that organic matter shrinkage due to hydrocarbon generation and clay mineral transformation both affect organo-clay complex pore-fracture formation.(3)At high thermal maturity,the Qingshankou Formation shale is dominated by nano-scale organo-clay complex pore-fractures with the percentage reaching more than 70%of total pore space.The spatial connectivity of organo-clay complex pore-fractures is significantly better than that of organic pores.It is suggested that organo-complex pore-fractures are the main pore space of laminar shale at high thermal maturity and are the main oil and gas accumulation space in the core area of continental shale oil.The discovery of nano-scale organo-clay complex pore-fractures changes the conventional view that inorganic pores are the main reservoir space and has scientific significance for the study of shale oil formation and accumulation laws. 展开更多
关键词 Songliao Basin Cretaceous Qingshankou Formation laminar shale oil nanoscale organo-clay complex pore-fractures organo-clay complex diagenesis
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