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Effect of Thermal Cycle on Microstructure and Fracture Morphology in HAZ of HQ130 Steel 被引量:4
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作者 Li Yajiang Zou Zengda +2 位作者 Cheng Zhunian Wei Xing Jiang Quanchang 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 1996年第2期38-43,共6页
The effect of different peak temperature(Tp) and cooling time (t8/5) on microstructure, hardness, impact toughness and fracture morphology in the heat-affected zone (HAZ) of HQ130 steel was studied by using weld therm... The effect of different peak temperature(Tp) and cooling time (t8/5) on microstructure, hardness, impact toughness and fracture morphology in the heat-affected zone (HAZ) of HQ130 steel was studied by using weld thermo-simulation test. Experimental results indicate that the impact toughness and hardness decrease with the decrease of Tpor increase of t8/5 under the condition of a single thermal cycle. There is a brittle zone in the vicinity of Tp= 800℃, where the impact toughness is considerably low. There is a softened zone in the vicinity of Tp=700℃, where the hardness decreases but the toughness increases. In the practical application of multi-layer and multipass welding, the welding heat input should be strictly limited (t8/5≤20s) so as to reduce the softness and brittleness in the HAZ of-HQ130 steel. 展开更多
关键词 high strength steel welding thermal cycle heat-affected zone MICROSTRUCTURE impact toughness
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Synthesis and Crystal Structure of a N,N,N′-tri(2-hydroxy-5-methylbenzyl)-1,2-ethanediamine 被引量:2
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作者 王暖升 汪永涛 +1 位作者 李俊英 李天铎 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第11期1533-1536,共4页
An aminophenol ligand, N,N,N'-tri(2-hydroxy-5-methylbenzyl)-l,2-ethanediamine, was prepared through the Marmich reaction, and structurally characterized by NMR, IR, MS and single-crystal X-ray diffraction. The titl... An aminophenol ligand, N,N,N'-tri(2-hydroxy-5-methylbenzyl)-l,2-ethanediamine, was prepared through the Marmich reaction, and structurally characterized by NMR, IR, MS and single-crystal X-ray diffraction. The title compound (C26H32N2O3, Mr = 420.54) belongs to the monoclinic system, space group P21/n with a = 8.6233(14), b = 10.2655(16), c = 26.017(4) A, β = 95.797(2)°, V = 2291.3(6) A^3, Z = 4, the final R = 0.0461 and wR = 0.1139 for 4267 unique reflections (Rint = 0.028) with 11691 observed ones (I〉 2a(I)). 展开更多
关键词 Mannich reaction aminophenol ligand crystal structure Mannich reaction aminophenol ligand crystal structure
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Simultaneous Synchronization and Anti-Synchronization of Two Identical New 4D Chaotic Systems 被引量:2
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作者 GUO Rong-Wei 《Chinese Physics Letters》 SCIE CAS CSCD 2011年第4期15-18,共4页
We investigate the synchronization and anti-synchronization of the new 4D chaotic system and propose a same adaptive controller in the form which not only synchronizes,but also anti-synchronizes two identical new 4D c... We investigate the synchronization and anti-synchronization of the new 4D chaotic system and propose a same adaptive controller in the form which not only synchronizes,but also anti-synchronizes two identical new 4D chaotic systems.Numerical simulations verify the correctness and the effectiveness of the proposed theoretical results. 展开更多
关键词 CHAOTIC verify identical
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THEORY OF NONLOCAL ASYMMETRIC ELASTIC SOLIDS 被引量:1
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作者 高键 陈至达 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 1992年第9期793-804,共12页
In this paper, a nonlinear theory of nonlocal asymmetric, elastic solids is developed on the basis of basic theories of nonlocal continuum field theory and nonlinear continuum mechanics. It perfects and expands the no... In this paper, a nonlinear theory of nonlocal asymmetric, elastic solids is developed on the basis of basic theories of nonlocal continuum field theory and nonlinear continuum mechanics. It perfects and expands the nonlocal elastic field theory developed by Eringen and others. The linear theory of nonlocal asymmetric elasticity developed in [1] expands to the finite deformation. We show that there is the nonlocal body moment in the nonlocal elastic solids. The nonlocal body moment causes the stress asymmetric and itself is caused by the covalent bond formed by the reaction between atoms. The theory developed in this paper is applied to explain reasonably that curves of dispersion relation of one-dimensional plane longitudinal waves are not similar with those of transverse waves. 展开更多
关键词 Continuum mechanics Crystal lattices DEFORMATION Dispersion (waves) Elastic waves Mathematical models SOLIDS Stresses
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Synthesis and Crystal Structure of One New Coordination Polymer: [Ni(qptc)_(0.5)(bpp)( H_2O)]_n 被引量:1
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作者 朱汇源 张伟 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第12期1701-1706,共6页
Solvothermal reaction of aromatic terphenyl-2,5,2',5'-tetracarboxylic acid (H4qptc) ligand and the transitional metal cation of Nin in the presence of 1,3-bi(4-pyri- dyl)propane (bpp) affords one new coordinat... Solvothermal reaction of aromatic terphenyl-2,5,2',5'-tetracarboxylic acid (H4qptc) ligand and the transitional metal cation of Nin in the presence of 1,3-bi(4-pyri- dyl)propane (bpp) affords one new coordination polymer, [Ni(qptc)0.5(bpp)(H2O)], (1). The structure has been determined by single-crystal X-ray diffraction analysis and further characterized by elemental analysis, IR, TGA, and magnetism. The qptc4- acts as a H-shaped ligand linking the NiⅡ centers together to form a 2D polymeric [Ni(qptc)0.5], layer consisting of alternately arranged left- and right-handed helical chains. Each 2D polymeric [Ni(qptc)0.5], layer is further linked through the bridging bpp ligands, thus resulting in a unique (3,4)- connected network with the (62.8)(62. 84) topology. The crystal of 1 crystallizes in monoclinic, space group C2/c with a = 16.088(5), b = 14.913(5), c = 18.849(6) A, β= 100.982(4), V= 4439(2) A3, Z= 8, C24H21N2NiO5, Mr = 476.14, Dc = 1.425 g/cm3, F(000) = 1976 and μ(MoKa) = 0.912 mm-1. The final R = 0.0584 and wR = 0.1131 for 3894 observed reflections with Ⅰ 〉 20(I) and R = 0.1224 and wR = 0.1279 for all data. 展开更多
关键词 terphenyl-2 S 2′ 5′-tetracarboxylic acid 1 3-bi(4-pyridyl)propane nickel(Ⅱ)
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Determination of Triclocarban, Triclosan and Methyl-Triclosan in Environmental Water by Silicon Dioxide/Polystyrene Composite Microspheres Solid-Phase Extraction Combined with HPLC-ESI-MS 被引量:1
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作者 Yinan Wang Pengfei Li +3 位作者 Yan Liu Bing Chen Jinyu Li Xikui Wang 《Journal of Geoscience and Environment Protection》 2013年第2期13-17,共5页
This paper developed a sensitive and efficient analytical method for triclocarban (TCC), triclosan (TCS) and Methyl-triclosan (MTCS) determination in environmental water, which involves enrichment by using silicon dio... This paper developed a sensitive and efficient analytical method for triclocarban (TCC), triclosan (TCS) and Methyl-triclosan (MTCS) determination in environmental water, which involves enrichment by using silicon dioxide/polystyrene composite microspheres solid-phase extraction and detection with HPLC-ESI-MS. The influence of several operational parameters, including the eluant and its volume, the flow rate and acidity of water sample were investigated and optimized. Under the optimum conditions, the limits of detection were 1.0 ng/L, 2.5 and 4.5 ng/L for TCC, TCS, and MTCS, respectively. The linearity of the method was observed in the range of 5-2000 ng/L, with correlation coefficients (r2) >.99. The spiked recoveries of TCC, TCS and MTCS in water sampleswereachieved in the range of 89.5% -96.8% with RSD below 5.7%. The proposed method has been successfully applied to analyze real water samples and satisfactory results were achieved. 展开更多
关键词 TRICLOCARBAN TRICLOSAN SOLID-PHASE Extraction Silicon Dioxide/Polystyrene Composite MICROSPHERES HPLC-ESI-MS/MS
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Deposition and Electrochemical Corrosion Behavior of Electroless Ni-P/Ni-W-P Duplex Plating on Mild Steel Substrate 被引量:1
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作者 Oioyede Olamilekan Razaq Zhu Liu Hong Liu 《材料科学与工程(中英文B版)》 2014年第2期13-19,共7页
关键词 电化学腐蚀行为 沉积 场发射扫描电子显微镜 化学镀NI-P 钢基板 低碳 双面 耐腐蚀性
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Thermodynamic Analysis of the Fracture Inheritance in Overheated Steels
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作者 李林 徐祖耀 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 1989年第3期157-160,共4页
Based on the experimental result that Cr and C segregated on the prior grain boundaries of austenite in overheated steels,causing the inheritance of fracture mode after re-austeni- tization,a thermodynamic analysis is... Based on the experimental result that Cr and C segregated on the prior grain boundaries of austenite in overheated steels,causing the inheritance of fracture mode after re-austeni- tization,a thermodynamic analysis is conducted through the calculation of equilibrium segregation amount of Cr and C in grain boundary at 860 and 1050℃ and the segregation kinetics of Cr is also calculated.Thermodynamic calculation gives an evidence that the segregation of Cr and C at grain boundaries may be regarded as one of the mechanisms of the fracture inheritance in overheated steels. 展开更多
关键词 fracture inheritance overheated steel SEGREGATION thermodynamic calculation
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Scale Effects and a Method for Similarity Evaluation in Micro Electrical Discharge Machining
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作者 LIU Qingyu ZHANG Qinhe +3 位作者 WANG Kan ZHU Guang FU Xiuzhuo ZHANG Jianhua 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第6期1193-1199,共7页
Electrical discharge machining(EDM) is a promising non-traditional micro machining technology that offers a vast array of applications in the manufacturing industry. However, scale effects occur when machining at th... Electrical discharge machining(EDM) is a promising non-traditional micro machining technology that offers a vast array of applications in the manufacturing industry. However, scale effects occur when machining at the micro-scale, which can make it difficult to predict and optimize the machining performances of micro EDM. A new concept of "scale effects" in micro EDM is proposed, the scale effects can reveal the difference in machining performances between micro EDM and conventional macro EDM. Similarity theory is presented to evaluate the scale effects in micro EDM. Single factor experiments are conducted and the experimental results are analyzed by discussing the similarity difference and similarity precision. The results show that the output results of scale effects in micro EDM do not change linearly with discharge parameters. The values of similarity precision of machining time significantly increase when scaling-down the capacitance or open-circuit voltage. It is indicated that the lower the scale of the discharge parameter, the greater the deviation of non-geometrical similarity degree over geometrical similarity degree, which means that the micro EDM system with lower discharge energy experiences more scale effects. The largest similarity difference is 5.34 while the largest similarity precision can be as high as 114.03. It is suggested that the similarity precision is more effective in reflecting the scale effects and their fluctuation than similarity difference. Consequently, similarity theory is suitable for evaluating the scale effects in micro EDM. This proposed research offers engineering values for optimizing the machining parameters and improving the machining performances of micro EDM. 展开更多
关键词 Electrical Discharge Machining (EDM) micro EDM Scale effect Similarity theory Similarity evaluating method
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Phylogeny of Saccharina and Laminaria(Laminariaceae, Laminariales, Phaeophyta) in sequence-tagged-site markers
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作者 曲洁琼 张静 +3 位作者 王绪敏 池姗 刘翠 刘涛 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2014年第1期22-33,共12页
Laminaria and Saccharina have recently been recognized as two independent clades from the former genus Laminaria. Traditional morphological taxonomy is being challenged by molecular evidence from both nucleus and plas... Laminaria and Saccharina have recently been recognized as two independent clades from the former genus Laminaria. Traditional morphological taxonomy is being challenged by molecular evidence from both nucleus and plastid. Intensive work is in great demand from the perspective of genome colinearity. In this study, 118 sequence-tagged site(STS) markers were screened for phylogenetic analyses, 29 based on genome sequences, while 89 were based on expressed sequence tag(EST) sequences. EST-based STS marker development(29.37%) had an effi ciency twice as high as genome-sequence-based development(9.48%) as a result of high conservation of gene transcripts among the relative species. S. ochotensis, S. religiosa, S. japonica, and L. hyperborea showed great homogeneity in all 118 STS markers. Our result supports the view that the diversifi cation between the genera Saccharina and Laminaria was a more recent event and that Saccharina and Laminaria shared high phylogenetic affi nity. However, when it came to the single nucleotide polymorphism(SNP) level among the 41 SNPs, L. hyperborea owned 29 unique SNPs against 12 within the left three Saccharina species and 12 of the 13 indels were supposedly unique for L. hyperborea, indicated by its high variability. Originating from homologous ancestors, species between the recently diverged genera Laminaria and Saccharina may have taken in enough mutations at the SNP level only, in spite of different evolutionary strategies for better adaptation to the environment. Our study lays a solid foundation from a new perspective, although more accurate phylogenetic analysis is still needed to clarify the evolutionary traces between the genera Saccharina and Laminaria. 展开更多
关键词 LAMINARIA PHYLOGENETICS SACCHARINA sequence-tagged site (STS) single nucleotide polymorphism (SNP)
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Imprints of molecular orbitals using photoelectron angular distribution by strong laser pulses of circular polarization
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作者 任向河 吴艳 +2 位作者 张敬涛 马慧 许玉龙 《Chinese Physics B》 SCIE EI CAS CSCD 2013年第7期148-152,共5页
We theoretically investigate the strong-field ionization of H+2 molecules in four different electronic states by calculating photoelectron angular distributions in circularly polarized fields. We find that the struct... We theoretically investigate the strong-field ionization of H+2 molecules in four different electronic states by calculating photoelectron angular distributions in circularly polarized fields. We find that the structure of photoelectron angular distribution depends on the molecular orbital as well as the energy of the photoelectron. The location of main lobes changes with the symmetric property of the molecular orbital. Generally, for molecules with bonding electronic states, the photoelectron’s angular distribution shows a rotation of π/2 with respect to the molecular axis, while for molecules with antibonding electronic states, no rotation occurs. We use an interference scenario to interpret these phenomena. We also find that, due to the interference effect, a new pair of jets appears in the waist of the main lobes, and the main lobes or jets of the photoelectron’s angular distribution are split into two parts if the photoelectron energy is sufficiently high. 展开更多
关键词 photoelectron angular distributions circular polarization laser field PHOTOIONIZATION MOLECULE
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Resourceful Utilization of Tannery Wastewater
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作者 Wang Chen Wang Xikui Ding Maochen Zhang Chaoyu 《Chinese Journal of Population,Resources and Environment》 2012年第1期116-121,共6页
Leather industry is an important light industry in China.Leather making requires a series of chemical treatment.Degreasing,unhairing and chrome tanning wastewaters are the main portions of tannery wastewater.Reclaimin... Leather industry is an important light industry in China.Leather making requires a series of chemical treatment.Degreasing,unhairing and chrome tanning wastewaters are the main portions of tannery wastewater.Reclaiming and reusing these wastewaters can eliminate 80% of COD,75% of BOD,95% of chromium and 93% of sulfuret,furthermore reduce environment impact,decrease treatment costs,save chemicals and water.Some application methods of wastewater reclamation and reuse for different operations were reported.The suitable reclamation and reuse technologies can enable leather making processes more rational,and realize the recovery and recycle of several chemicals in the tannery.Resourceful utilization of tannery wastewater should mate with renovating production technology,updating equipment,and must be guaranteed sufficiently by environmental protection measures. 展开更多
关键词 leather industry WASTEWATER waste liquor treatment resourceful utilization
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Modeling and Rendering in the Three-Dimensional Effect in Rhino for Lady's High Boots
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作者 王立新 李明辉 《Journal of Donghua University(English Edition)》 EI CAS 2011年第2期196-199,共4页
In recent years, the computer drawing technology that deals with three-dimensional (3D) design of footwear has become hot topics. Rhino is a kind of common and practical 3D design software with strong drawing and rend... In recent years, the computer drawing technology that deals with three-dimensional (3D) design of footwear has become hot topics. Rhino is a kind of common and practical 3D design software with strong drawing and rendering graphics function, which is widely used to design industrial products. In this paper, through decomposition and modeling, modeling and drawing methods were analyzed in various parts of footwear by Rhino, as well as the smooth technology and adjustments to its profile curve by an example of lady's high boots. Finally, through a series introductions of rendering effects for footwear in color, light perception, grain characteristic, and 3D graphics, the main technical essential is achieved and difficulties in design of overall footwear styles are solved. 展开更多
关键词 3D effect FOOTWEAR RHINO rendering and modeling
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Synthesis and Crystal Structure of 4-(N,N-Diphenylamino)styrene- 4′-N-methylpyridinium Iodine
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作者 谢瑞兴 张献 +3 位作者 黄宝丽 姚金水 孟祥龙 于晓强 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2011年第11期1609-1613,共5页
The title compound 4-(N,N-diphenylamino)styrene-4'-N-methylpyridinium iodine (abbreviated to PASMPI) was synthesized by a facile condensation reaction with a high yield. The red crystal including a molecule of CH... The title compound 4-(N,N-diphenylamino)styrene-4'-N-methylpyridinium iodine (abbreviated to PASMPI) was synthesized by a facile condensation reaction with a high yield. The red crystal including a molecule of CHCI3 was obtained by recrystallization in chloroform/ethanol. Its crystal structure was determined by a four-circle diffractometer. The crystal data: C26H23N2ICHCI3, Mr = 609.73, orthorhombic, space group Pbca, a = 15.422(5), b = 14.042(5), c = 24.693(5) A, V= 5347(3) A^3, Z = 8, Dc = 1.515 g/cm^3, F(000) = 2432,μ(MoKa) = 0.057 mm^-1, the final R = 0.0439 and wR = 0.0772. The results reveal that the molecule is a completely reverse system. The molecular rotation from non-coplanar to coplanar may play an important role in increasing the fluorescence intensity under the condition of staining DNA. 展开更多
关键词 PASMPI SYNTHESIS crystal structure
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The extraction and preliminary characterization of paint oil and paint wax
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作者 Ren Yingjie Wu Maoyu Zhang Feilong 《中国生漆》 2012年第2期9-14,共6页
研究漆籽油和漆蜡提取的最佳工艺,进行单因素实验,对不同品种漆油进了红外分析。结果表明:漆蜡的最佳工艺条件是:石油醚(30℃~60℃)作为提取剂,提取温度为50℃,固液比为1∶20,提取时间12h,漆籽皮的目数是大于100目;漆油的最佳工艺... 研究漆籽油和漆蜡提取的最佳工艺,进行单因素实验,对不同品种漆油进了红外分析。结果表明:漆蜡的最佳工艺条件是:石油醚(30℃~60℃)作为提取剂,提取温度为50℃,固液比为1∶20,提取时间12h,漆籽皮的目数是大于100目;漆油的最佳工艺条件是:石油醚(30℃~60℃)作为提取剂,提取温度为50℃,固液比为1∶30,提取时间3h,漆籽皮的目数是大于100目。通过萃取所得的漆油在红外图谱上出峰位置基本一致,表明其化学成分基本相同。 展开更多
关键词 漆籽 漆蜡 漆油 提取 化学组成
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Production of high-quality agarwood in Aquilaria sinensis trees via whole-tree agarwood-induction technology 被引量:31
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作者 Xing Li Zhang Yang Yang Liu +5 位作者 Jian He Wei Yun Yang Zheng Zhang Jun Qing Huang Huai Qiong Chen Yu Jun Liu 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第6期727-730,共4页
We used whole-tree agarwood-induction technology to produce agarwood from Aquilaria sinensis trees within 20 months, and evaluated the quality of this agarwood. The results showed its characteristics were similar to t... We used whole-tree agarwood-induction technology to produce agarwood from Aquilaria sinensis trees within 20 months, and evaluated the quality of this agarwood. The results showed its characteristics were similar to those of high-grade wild agarwood in terms of texture, chemical constituents, essential oil content, and ethanol-soluble extract content, with the lattermost quality far surpassing the requirement of traditional Chinese medicine agarwood, as indicated in Chinese Pharmacopoeia 2010. To the best of our knowledge, this is first study to show that high-quality agarwood can be produced in whole A. sinensis trees via a chemically induced technology. 展开更多
关键词 AGARWOOD Aquilaria sinensis Chemically induced QUALITY Whole-tree agarwood-induction technology
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Phosphorus release potential and pollution characteristics of sediment in downstream Nansi Lake, China 被引量:6
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作者 Zhijian LI Qinyan YUE +2 位作者 Baoyu GAO Yanwen WANG Qing LIU 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2012年第2期162-170,共9页
The research aimed to evaluate present and potential phosphorous pollution due to high sedimentary phosphorus load and release from sediment, when external phosphorus was reduced in downstream Nansi Lake. Pollution lo... The research aimed to evaluate present and potential phosphorous pollution due to high sedimentary phosphorus load and release from sediment, when external phosphorus was reduced in downstream Nansi Lake. Pollution load of the sediment and overlying water was investigated. Kinetics and isotherms of adsorption/release of sedimentary phosphorus were studied to determine equilibrium phosphate concentration (EPCo) and release potential. Kinetics of phosphorus adsorption on sediment and release from sediment were well described by both the pseudo-first-order rate equation and the pseudo-second- order rate equation, but more appropriate to the pseudo- second-order rate equation with the adsorption/release capacity more close to the measured values, suggesting that the processes were chemically rate controlled and dependent on adsorption capacity. Soluble reactive phosphorus (SRP) sorption isotherms on sediment were best fitted by the modified Langmuir model indicating a monolayer adsorption. By comparing EPC0 and SRP of water, the status (adsorption, releasing or in equilibrium) of sediment phosphorus could be determined. The sediments at site S l, S3, S4, S5, and S7 where the EPC0s were greater than the SRPs, had a potential to release phosphorus into the water column. However, those sediments at S9, S10, and S 12, where the EPC0s were approximately equal to the SRPs, were in impermanent equilibrium with overlying water in status of phosphorus, the sediments can be likely to release phosphorus to the water column once the equilibrium was broken. Therefore, sedimentary phos- phorus can be a secondary pollution source in downstream Nansi Lake. 展开更多
关键词 Nansi Lake SEDIMENT PHOSPHORUS RELEASE
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Selective derivatization of oxime-blocked tolylene-2,4-diisocyanate 被引量:2
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作者 Yang Sang Peng-Fei Yang Tian-Duo Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2013年第11期1019-1022,共4页
A selective reaction of cyclohexanone oxime-blocked tolylene-2,4-diisocyanate(2,4-TDI)with amino siloxane was observed,in which amines were capable of discriminating two reactive groups in the 2,4-TDI molecule.Thus,... A selective reaction of cyclohexanone oxime-blocked tolylene-2,4-diisocyanate(2,4-TDI)with amino siloxane was observed,in which amines were capable of discriminating two reactive groups in the 2,4-TDI molecule.Thus,tolylene-2-tert-butyldimethylsilyloxyethyl carbamide-4-cyclohexanone oxime carbamate was synthesized and its precise structure was determined by single-crystal X-ray diffraction.Moreover,it was found that oxime-blocked isocyanate could react selectively with the–NH2group with the–OH group unprotected in ethanolamine. 展开更多
关键词 Cyclohexanone oxime Tolylene-2 4-diisocyanate Ethanolamine Selective reactions
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Synthesis and characterization of asymmetric substituted dicarbamates 被引量:1
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作者 Chao Zhao Peng Fei Yang Shun Ping Wang Jun Ying Li Tian Duo Li 《Chinese Chemical Letters》 SCIE CAS CSCD 2011年第10期1167-1170,共4页
Several new asymmetric substituted dicarbamates were synthesized with a convenient route.Firstly,tolylene-2,4-diisocyanate dimmer was obtained from monomer with tributylphosphine as catalyst.Then,the dimmer reacted wi... Several new asymmetric substituted dicarbamates were synthesized with a convenient route.Firstly,tolylene-2,4-diisocyanate dimmer was obtained from monomer with tributylphosphine as catalyst.Then,the dimmer reacted with alcohol(R^1OH) to prepare carbamate substituted uretidione.Finally,uretidione ring was opened and the released isocyanate reacted with another alcohol (R^2OH,R^1≠R^2). 展开更多
关键词 Asymmetric substituted dicarbamates Tolylene-2 4-diisocyanate Uretidione
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Effect of Electrolytes and Polymers on the Thixotropy of Mg-AI-Layered Double Hydroxides/Kaolinite Dispersions 被引量:1
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作者 戴肖南 侯万国 段洪东 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2011年第10期2027-2033,共7页
The effect of electrolytes (NaCl and CaCl2) and polymers (CPAM and HPAM) on the thixotropy of Mg-Al-layered double hydroxide (LDHs)/kaolinite dispersions has been investigated. It was observed that the type of t... The effect of electrolytes (NaCl and CaCl2) and polymers (CPAM and HPAM) on the thixotropy of Mg-Al-layered double hydroxide (LDHs)/kaolinite dispersions has been investigated. It was observed that the type of thixotropy in LDH/kaolinite dispersions may be affected by NaCl, but not by CaCl2 in range of concentration of interest. The type of thixotropy in LDH/kaolinite dispersion with R=0 transformed from positive thixotropy to complex thixotropy and at last positive thixotropy again with the concentration of NaC1 in range of 0.00-0.10 mol·L^-1; the type of thixotropy in LDHs/kaolinite dispersions with R = 0.25 transformed from complex thixotropy to positive thixotropy and then complex thixotropy again with the concentration of NaC1 in range of 0.00-0.10 mol·L^-. The type of thixotropy in LDH/kaolinite dispersion with R=0 may be not affected by cationic polyacrylamide (CPAM) and hydrolyzed polyacrylamide (HPAM); but the LDHs/kaolinite dispersions with R=0.25 transformed from complex thixotropy to positive thixotropy with the both polymers concentration in range of interest, which indicated that the microstructure of the dispersion changed from weak folc sediments structure to steric network structure. 展开更多
关键词 structure POLYMER THIXOTROPY layered double hydroxides KAOLINITE
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