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一维链状冠醚配合物:{[K(DB18-crown-6)]_2(CH_3CN)}[Pt(SCN)_4]的合成与晶体结构(英文)
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作者 李大成 刘颖 窦建民 《聊城大学学报(自然科学版)》 2003年第2期7-8,71,共3页
合成了一维链状冠醚配合物:{[K(DB18-crown-6)]_2(CH_3CN)}[Pt(aSCN)_4],通过元素分析、红外光谱、单晶X-射线衍射对配合物结构进行表征,结果表明:配合物为单斜晶系,空间群c2/c a=2.590 4(8),b=1.365 4(4),c=1.817 0(6)nm,β=123.811(4)... 合成了一维链状冠醚配合物:{[K(DB18-crown-6)]_2(CH_3CN)}[Pt(aSCN)_4],通过元素分析、红外光谱、单晶X-射线衍射对配合物结构进行表征,结果表明:配合物为单斜晶系,空间群c2/c a=2.590 4(8),b=1.365 4(4),c=1.817 0(6)nm,β=123.811(4)°,V=5.339(3)nm^3,Z=4,D_(calcd)=1.577g/cm^3,F(000)=2 552,R_1=0.051,wR_2=0.141 1.配合物由两个[K(DB18-crown-6)]^+配阳离子、一个[Pt(aSCN)_4]^(2-)配阴离子和一个CH_3CN分子组成,相邻[K(DB18-crown-6)]_2[Pt(aSCN)_4]离子对通过CH_3CN分子中的N原子形成一维链状结构。 展开更多
关键词 一维链状冠醚配合物 铂配合物 合成 晶体结构 {[K(DB18-crown-6)]2(CH3CN)}[Pt(SCN)4] 结构表征
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[{Pt_4(en)_4(NHCO^tBu)_4}{Tl(18-crown-6)}_2](PF_6)_6的合成与晶体结构(英文) 被引量:1
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作者 吾国强 陈万芝 《无机化学学报》 SCIE CAS CSCD 北大核心 2006年第4期761-764,共4页
The compound [{Pt4(en)4(NHCOtBu)4}{Tl(18-crown-6)}2](PF6)6 has been synthesized by a simple one-potmulticomponent reaction. Its structure was determined by X-ray single crystal diffraction analysis. The cation oft... The compound [{Pt4(en)4(NHCOtBu)4}{Tl(18-crown-6)}2](PF6)6 has been synthesized by a simple one-potmulticomponent reaction. Its structure was determined by X-ray single crystal diffraction analysis. The cation ofthe compound consists of one linearly arranged [Pt4(en)4(NHCOtBu)4]4+ chain and two [Tl(18-crown-6)]+ ions located atthe two ends of the platinum chain. The complex crystallizes in a triclinic P1 with a=1.060 5(1), b=1.252 3(1), c=2.015(2) nm, α=107.430(2)°, β=91.032(2)°, γ=101.910(2)°, V=2.489 6(4) nm3, Z=2, R1=0.074 4, wR2(I>2σ(I))=0.2225, S=1.062. CCDC: 294083. 展开更多
关键词 晶体结构 18-冠-6
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Lanthanum(Ⅲ) sorption studies on poly[dibenzo-18-crown-6] and its separation from uranium(Ⅵ) and thorium(Ⅳ) in L-valine medium 被引量:2
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作者 S.R.Sabale D.V.Jadhav B.S.Mohite 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第5期825-829,共5页
The sorption study of La(Ⅲ) was carried out on poly[dibenzo-18-crown-6] and L-valine medium. The quantitative adsorption of La(Ⅲ) was found at 1×10-2 to 1×10-5 mol/L L-valine. The various eluting agents we... The sorption study of La(Ⅲ) was carried out on poly[dibenzo-18-crown-6] and L-valine medium. The quantitative adsorption of La(Ⅲ) was found at 1×10-2 to 1×10-5 mol/L L-valine. The various eluting agents were found efficient eluents for La(Ⅲ). The capacity of crown polymer for La(Ⅲ) was found to be 0.43 ±0.01 mmol/g. The tolerance limit of various cations and anions for La(Ⅲ) was determined. La(Ⅲ) was quantitatively separated from other metal ions in binary as well as multicomponent mixtures. The study was extended to sequential separation of La(Ⅲ), U(VI) and Th(IV). The good separation yields were obtained and had good reproducibility (±2%). The method incorporated the determination of La(Ⅲ) in real sample. The method was simple, rapid and selective. 展开更多
关键词 La(Ⅲ) L-VALINE poly[dibenzo-18-crown-6] SORPTION SEPARATION rare earths
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Synergistic Effect in Mixed Capillary Gas Chromatographic Stationap Phases Containing Heptakis(2,3,6-tri-o-pentyl)-β-cyclodextrin and Dibenzo-18-crown-6 被引量:1
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作者 Li Ming YUAN Ruo Nong FU +3 位作者 Xue Xian CHEN Shi Hong GUl Rong Ji DAI (Chemistry Department of Yunnan Normal University.Kunming 650092)(Department of Chemical Engineering.Beijing institute of Technology,BEijing 100081)(Solar Energy Research Institute ofyunna 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第3期223-226,共4页
used-silical capillary columns containing heptakis(2、3、6-tri-o-pentyl)-β-cyclodextrinand dibenzo-18-crown-6 were prepared.By studying the selectivity of mixed stationary phases forsome solute pairs.as well a... used-silical capillary columns containing heptakis(2、3、6-tri-o-pentyl)-β-cyclodextrinand dibenzo-18-crown-6 were prepared.By studying the selectivity of mixed stationary phases forsome solute pairs.as well as comparing with the heptakis(2.3、6-tri-O-pentyl)-β-cyclodextrin and thedibenzo-18-crown-6 used as individual stationary phase、the synergistic effects were observed.These effects were affected by the column temperature.mixed ratio and linear velocity of carrier gas. 展开更多
关键词 Gas chromatography mixed stationary phase synergistic effect heptakis(2.3.6-tri-o-pentyl)-β-cyclodextrin DIBENZO-18-crown-6
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Synthesis and Crystal Structure of 3,3'-Dimethyl-dibenzo-18-crown-6 被引量:1
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作者 NIU Mei-Ju DOU Jian-Min WANG Da-Qi LI Da-Cheng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第6期757-760,共4页
3,3′-Dimethyl-dibenzo-18-crown-6 was synthesized and characterized by elemental analysis, FT-IR, ^1H NMR, UV, MS spectra and X-ray single-crystal diffraction. It belongs to orthorhombic, space group Pna21 with a = 8.... 3,3′-Dimethyl-dibenzo-18-crown-6 was synthesized and characterized by elemental analysis, FT-IR, ^1H NMR, UV, MS spectra and X-ray single-crystal diffraction. It belongs to orthorhombic, space group Pna21 with a = 8.0790(18), b = 16.780(4), c = 15.222(3) .A, Z= 4, V= 2063.6(8) A3 Dc = 1.250 g/cm^3,μ = 0.090 mm^-1, F(000) = 832, R = 0.0474 and wR = 0.1103. According to structural analysis, the title compound possesses a boat-like configuration. 展开更多
关键词 crown ether 3 3'-dimethyl-dibenzo-18-crown-6 SYNTHESIS crystal structure
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{[K.18-Crown-6]Br3}n:保护胺和醇的三溴化催化剂(英文)
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作者 Gholamabbas Chehardoli Mohammad Ali Zolfigol Fateme Derakhshanpanah 《催化学报》 SCIE EI CAS CSCD 北大核心 2013年第9期1730-1733,共4页
{[K.18-Crown-6]Br3}n , a unique tribromide-type catalyst, was utilized for the N-boc protection of amines and trimethylsilylation (TMS) and tetrahydropyranylation (THP) of alcohols. The method is general for the prepa... {[K.18-Crown-6]Br3}n , a unique tribromide-type catalyst, was utilized for the N-boc protection of amines and trimethylsilylation (TMS) and tetrahydropyranylation (THP) of alcohols. The method is general for the preparation of N-boc derivatives of aliphatic (acyclic and cyclic) and aromatic, and primary and secondary amines and also various TMS-ethers and THP-ethers. The simple separation of the catalyst from the product is one of the many advantages of this method. 展开更多
关键词 {[K.18-crown-6]Br3}n TRIMETHYLSILYLATION TETRAHYDROPYRANYLATION Alcohol Organic TRIBROMIDE N-boc protection of amine
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Fluorescence-quenching of Tryptophan Ion-18-crown-6 Complex——A Different Observation from Its Neutral Counterpart
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作者 YU Qing CAO Jie +1 位作者 LIU Tao WANG Zhi-xiang 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2009年第3期362-367,共6页
It is well-known that primary amines form inclusive complexes with crown ethers. This kind of noncovalently inclusive complexes, exemplified tryptophan complex with 18-crown-6, was studied by combination of two experi... It is well-known that primary amines form inclusive complexes with crown ethers. This kind of noncovalently inclusive complexes, exemplified tryptophan complex with 18-crown-6, was studied by combination of two experimental methods, fluorimetry and mass spectrometry, with theoretical calculation. Fluorescence intensity of tryptophan in the absence and the presence of 18-crown-6 in aqueous HAc-NaAc buffer solution at pH=3.73 has been studied by fluorometry. The fuorescence intensity decreases significantly with increasing the concentration of 18-crown-6. The association constant K for the 1:1 complex of tryptophan ion-18-crown-6 was determined by means of fuorimetry. Mass spectrometric study of the complex gives direct evidence of the complex in the gas phase whose structure and binding energy are properly predicted by ab initio calculation. 展开更多
关键词 TRYPTOPHAN 18-crown-6 complex FLUORESCENCE Mass spectrometry Ab initio calculation
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Synthesis and Crystal Structure of a Sandwiched Trinuclear Complex [Tl_2(18-Crown-6)_2Pt(CN)_4]·2H_2O
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作者 LIU Feng-Hui CHEN Wan-Zhi WANG Da-Qi 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2006年第6期677-680,共4页
The trinuclear complex bis(18-crown-6)thallium tetracyanoplatinate [Tl2(1 8-crown- 6)2Pt(CN)4]·2H2O was prepared and its structure was determined by X-ray diffraction analysis. The compound (C28H52N4O14PtT... The trinuclear complex bis(18-crown-6)thallium tetracyanoplatinate [Tl2(1 8-crown- 6)2Pt(CN)4]·2H2O was prepared and its structure was determined by X-ray diffraction analysis. The compound (C28H52N4O14PtTl2, Mr = 1272.57) crystallizes in monoclinic, space group P21/n with a = 10.5180(10), b = 8.6162(8), c = 21.118(2) A, β= 92.577(2)°, V= 1911.9(3) A^3, Z = 2, Dc = 2.211 g/cm^3, F(000) = 1200,μ= 12.123 mm^-1, R = 0.0181 and wR = 0.0427. The linearly arranged three metals are sandwiched by two 18-crown-6 molecules. 展开更多
关键词 PLATINUM THALLIUM CYANIDE 18-crown-6 crystal structure
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Bibracchial Lariat Ethers(Ⅰ)——The Synthesis and Crystal Structure of the N,N'-bis(2-Methoxy-1-Naphthylmethyl)-4,13-Diaza-18-Crown-6 Sodium Iodide Complex
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作者 Ge Yuhua, Wang Defen and Hu Hongweng (Department of Chemistry, Nanjing University, Nanjing)Zhou Zhongyuan and Yu Kaibei (Chengdu Center of Analysis and Determination, Academic Sinica, Chengdu) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1992年第1期48-52,共5页
Diaza Crown ethers are versatile complexing reagents, their complexing abilities are dramatically modified by the electron donating atoms on substituents attached to the nitrogen if they can give a three-dimensional c... Diaza Crown ethers are versatile complexing reagents, their complexing abilities are dramatically modified by the electron donating atoms on substituents attached to the nitrogen if they can give a three-dimensional cavity as in cryptates. Hence the synthesis and characterization of bibracchial lariat ethers (BIBLES) have received much attention. In the preparation of new BIBLES, a complex Ⅱ was unexpectedly obtained. 展开更多
关键词 Bibracchial lariat ether Diaza-18-crown-6 derivative Crystal structure Sodium iodide complex
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REGIOSELECTIVE OXIDATION OF KETONE BY AN OXIDATIVE REAGENT SYSTEM KH/O_2/18-CROWN-6/THF:APPLICATION TO SYNTHESIS OF VARIOUS LACTONES
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作者 Wei Shan ZHOU Biao JIANG Shanghai Institute of Organic Chemistry,Chinese Academy of Sciences,345 Lingling Lu,Shanghai 200032.Xin Fu PAN Department of Chemistry,Lanzhou University,Lanzhou 730000. 《Chinese Chemical Letters》 SCIE CAS CSCD 1991年第7期505-508,共4页
the regioselectivity in the oxidation of different types of ketone compounds 1--6 with an oxidative reagent system,KH/O_2/18- Crown-6/THF is described.From these oxidative products,the various lactones have been prepa... the regioselectivity in the oxidation of different types of ketone compounds 1--6 with an oxidative reagent system,KH/O_2/18- Crown-6/THF is described.From these oxidative products,the various lactones have been prepared. 展开更多
关键词 THF REGIOSELECTIVE OXIDATION OF KETONE BY AN OXIDATIVE REAGENT SYSTEM KH/O2/18-crown-6/THF KH
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CdI<sub>2</sub>Extraction with 18-Crown-6 Ether into Various Diluents: Classification of Extracted Cd(II) Complex Ions Based on the HSAB Principle
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作者 Yoshihiro Kudo Yamato Ishikawa Hikaru Ichikawa 《American Journal of Analytical Chemistry》 2018年第11期560-579,共20页
CdI2 in water was extracted with 18-crown-6 ether (L) into 10 diluents at 298 K. The following equilibrium constants were determined or evaluated: some extraction constants (Kex/mol-3·dm9 & Kex,ip/mol-2·... CdI2 in water was extracted with 18-crown-6 ether (L) into 10 diluents at 298 K. The following equilibrium constants were determined or evaluated: some extraction constants (Kex/mol-3·dm9 & Kex,ip/mol-2·dm6 for CdLI2, Kex±/mol-2·dm6 for CdLI+ with I-, & Kex2±/mol-1·dm3 for CdL2+ with 2I-), conditional distribution constants (KD,I for I-, KD,CdLI for CdLI+, & KD,CdL for CdL2+) between the two phases, and an ion-pair formation constant (K1,org/mol-1·dm3) for CdLI+ and that (K2,org/mol-1·dm3) for CdLI2 in the organic (org) phases. Using the K1,org and K2,org values, acidities of the complex ions, CdL2+ and CdLA+ (A- = I-, Br-, & Cl-), in the 11 diluents were classified by applying the HSAB rule. Especially, the CdLA+ ions were classified as the soft acids in 9 diluents. Also, molar volumes (Vj/cm3·mol-1) of j = CdLI2 and CdL2+ were determined with the regular-solution-theory plot of logKex,ip vs. logKD,L and its pseudo-plot of logKD,CdL, respectively. Here, KD,L denotes the distribution constant of L between the two phases. So, sizes among CdLA2 and CdL2+ were compared by using the Vj values. Additionally, some distribution equilibrium potentials (dep/V) between the water and org bulk phases were topically calculated from an equation of KD,I with KSD,I, where the symbol KSD,I shows a standard distribution constant of I- at dep = 0 V for a given diluent. 展开更多
关键词 Ion-Pair Formation CONSTANTS HSAB Acidity Molar Volume Conditional DISTRIBUTION CONSTANTS DISTRIBUTION Equilibrium Potentials Cadmium Iodide 18-crown-6 ETHER
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Theoretical Study of Hydration Effects on the Selectivity of 18-Crown-6 Between K~+ and Na~+ 被引量:8
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作者 郭晓静 朱育丹 +3 位作者 魏明杰 吴喜明 吕玲红 陆小华 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2011年第2期212-216,共5页
分子的动力学(MD ) 和密度的联合功能的理论(DFT ) 计算被用来在 18-crown-6 的监禁下面学习 K+ 和 Na+ 离子的水和结构以便向 K+ 在 18-crown-6 的选择识别水的角色。光线的分发功能,协作数字,取向结构和相互作用精力被分析在 18-cro... 分子的动力学(MD ) 和密度的联合功能的理论(DFT ) 计算被用来在 18-crown-6 的监禁下面学习 K+ 和 Na+ 离子的水和结构以便向 K+ 在 18-crown-6 的选择识别水的角色。光线的分发功能,协作数字,取向结构和相互作用精力被分析在 18-crown-6/cation 建筑群调查 K+ 和 Na+ 的水和。K+ 和 Na+ 的计算大批浇的所有也为比较被进行。模拟结果证明在 K+ 的第一协作壳的水分子的取向分布比 Na+ 的那些对 18-crown-6 的监禁更敏感。以相互作用精力比 Na+ 在 18-crown-6 限制 K+ 是更有利的。好同意在 MD 结果之间被获得, DFT 结果。 展开更多
关键词 钠离子 保湿效果 密度泛函理论 径向分布函数 定向结构 分子动力学 相互作用能
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Chromatographic separation of Be(Ⅱ) from Mg(Ⅱ), Ca(Ⅱ), Sr(Ⅱ) and Ba(Ⅱ) using poly[dibenzo-18-crown-6] and L-arginine
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作者 Sandip R. Sabale Baburao S. Mohite 《Journal of Chemistry and Chemical Engineering》 2009年第6期37-43,共7页
关键词 色谱分离 二苯并 精氨酸 CA SR 多组分混合物 选择性分离
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CRYSTAL STRUCTURE OF DISODIUM DIAZA-18-CROWN-6-N, N'-DIACETATE PENTAHYDRATE
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作者 黄枢 周忠远 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1991年第3期175-179,共5页
The title compound was prepared from the reaction of diaza-18-crown-6 and sodium chloroacetate in aqueous solution and crystallized from ethanol solution by standing for a long time. The complex [Na(C16H28N2O8)·N... The title compound was prepared from the reaction of diaza-18-crown-6 and sodium chloroacetate in aqueous solution and crystallized from ethanol solution by standing for a long time. The complex [Na(C16H28N2O8)·Na(H2O)5]2Cl-·2H2O+·H2O (Mr = 655. 45) crystalizes in triclinic system,space group P1 with a = 9. 623(2),b = 10. 902(3),c=15. 867(3) A ;α= 104. 63(2),β= 105. 42(2),γ=99. 88(2)°,V = 1502. 3A3,Dc=1. 09gcm-3,Z = 2,F(000) = 516,final R=0. 075 for 3218 observed reflections. The donor atoms O(4) ,O(7) ,O(13) ,O(16) ,N(1) and N(10) from the crown ether as well as the oxygen atoms O(21) and O(26) from two car boxy lato anions are coordinated cooperatively to the Na(1)+ ion to form crown ether solvated cation in a tetragonal prismatic geometry. The O(22) of one carboxylato anion, which does not coordinate the Na(1) + ion,interacts with the Na(2)+ion together with the oxygen atoms of five water molecules to form a hydrated cation having a deformed octahedral configuration. 展开更多
关键词 晶体结构 二钠盐 二氮杂-18-冠(醚)-6-N N′-双乙酸钠 五水配合物
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CRYSTAL STRUCTURE OF N, N' -BIS ( 2-METHOXY-1-NAPH-THYLMETHYL)-4,13-DIAZA-18-CROWN-6 POTASSIUM IODIDE
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作者 王德木+分 郁开北 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1992年第1期61-64,共4页
Crystal of N , N'-bis(2-methoxy-l-naphthylmethyl)-4,13-diaza-18-crown-6 potassium iodide diethanol solvate[(C36H46N2O6)K]+I- · 2C2H5OH (Mr = 860. 47) is orthorhombic with space group Pcab, a = 17. 531(5), 6 =... Crystal of N , N'-bis(2-methoxy-l-naphthylmethyl)-4,13-diaza-18-crown-6 potassium iodide diethanol solvate[(C36H46N2O6)K]+I- · 2C2H5OH (Mr = 860. 47) is orthorhombic with space group Pcab, a = 17. 531(5), 6 = 21. 149(8), c = 23. 060(4)(?). F=8550. 00(?)3, Z = 8, F(000) = 3167. 64 and Dc=1. 337g/ cm3, μ = 8. 74cm-1, R = 0. 057. In the title complex, the donor atoms of the macro-ring are arranged in a twisted boat conformation. The potassium ion is octa-coordi-nated with four oxygen and two nitrogen atoms of the macro-ring and two oxygen atoms of the two side arms at the same side to form a distorted hexagonal bipyramid. 展开更多
关键词 晶体结构 N-N′-双(2-甲氧基-1-萘甲基)-4 13-二氮杂-18-冠(醚)-6 碘化钾
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外圆磨削18CrNiMo7-6力模型及表面完整性研究
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作者 王栋 陈磊 张志鹏 《中国机械工程》 EI CAS CSCD 北大核心 2024年第3期381-393,共13页
为了准确和有效地控制磨削参数对磨削力及表面完整性的影响,通过解析法,以磨粒与材料间的塑性变形、压痕理论以及剪切应变效应为理论依据,建立了三阶段的磨削力理论模型。选定棕刚玉砂轮进行磨削试验,探究了磨削参数对磨削力的影响以及... 为了准确和有效地控制磨削参数对磨削力及表面完整性的影响,通过解析法,以磨粒与材料间的塑性变形、压痕理论以及剪切应变效应为理论依据,建立了三阶段的磨削力理论模型。选定棕刚玉砂轮进行磨削试验,探究了磨削参数对磨削力的影响以及磨削参数和磨削力对表面完整性的影响,通过外圆横向磨削正交试验获得了外圆磨削最优工艺参数。结果表明,外圆磨削力模型法向磨削力和切向磨削力的预测平均误差分别为5.56%和7.08%;砂轮径向进给速度f_(r)对磨削力的影响最大,磨削宽度b次之,工件转速n_(w)和砂轮粒度的影响较小;f_(r)和b对残余应力的影响较大,砂轮粒度对表面粗糙度的影响最大;随着磨削力的增大,表面粗糙度值一直增大,残余应力先减小后增大,沿深度方向残余应力最大值先增大后减小,在试验所取参数条件下,影响残余应力的深度分布范围基本在20~40μm;最优工艺参数组合如下:f_(r)=0.15 mm/min,n_(w)=120 r/min,b=10 mm,砂轮粒度80。 展开更多
关键词 外圆磨削 横向磨削 磨削力模型 18CrNiMo7-6 表面完整性
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18CrNiMo7-6齿轮钢的热压缩变形行为及显微组织演变
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作者 吴晓东 黄寅舜 +1 位作者 张肖佩佩 王忠英 《机械工程材料》 CAS CSCD 北大核心 2024年第3期87-94,共8页
采用热模拟方法研究了18CrNiMo7-6齿轮钢在变形温度900~1150℃、应变速率0.01~5 s-1条件下的热压缩变形行为;建立了基于Arrhenius模型的全应变本构方程,采用该方程对流变应力曲线进行预测;根据动态材料模型绘制热加工图,并结合热加工图... 采用热模拟方法研究了18CrNiMo7-6齿轮钢在变形温度900~1150℃、应变速率0.01~5 s-1条件下的热压缩变形行为;建立了基于Arrhenius模型的全应变本构方程,采用该方程对流变应力曲线进行预测;根据动态材料模型绘制热加工图,并结合热加工图系统地研究显微组织演变特征。结果表明:试验钢的峰值应力随应变速率的增加或变形温度的降低而增大,动态回复和动态再结晶是热变形过程中的主要软化机制;采用建立的全应变本构方程预测得到流变应力曲线与试验结果基本吻合,预测真应力与试验结果的相对误差小于4.715%,说明该模型可以精确地模拟18CrNiMo7-6齿轮钢的热压缩变形行为。试验钢的适合热加工工艺参数为变形温度1050~1150℃、应变速率0.1~1 s^(-1),此时组织为均匀细小的再结晶晶粒,晶粒尺寸在5~15μm。随着变形温度的升高或应变速率的降低,原始奥氏体晶粒不断被动态再结晶晶粒取代,且动态再结晶程度和再结晶晶粒尺寸增大。 展开更多
关键词 18CrNiMo7-6齿轮钢 热变形 本构方程 热加工图 显微组织
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18CrNiMo7-6渗碳合金钢电解抛光参数研究 被引量:1
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作者 王书艳 张悦 +1 位作者 路留成 王刚 《热加工工艺》 北大核心 2024年第2期121-125,共5页
为提高18CrNiMo7-6渗碳合金钢表面变质层的电解抛光加工质量,开展18CrNiMo7-6渗碳合金钢表面变质层不同渗碳层深度下的电解抛光工艺分析与试验。结果表明,选择浓磷酸与浓硫酸混合溶液作为电解液,温度为40~45℃,首先研究18CrNiMo7-6渗碳... 为提高18CrNiMo7-6渗碳合金钢表面变质层的电解抛光加工质量,开展18CrNiMo7-6渗碳合金钢表面变质层不同渗碳层深度下的电解抛光工艺分析与试验。结果表明,选择浓磷酸与浓硫酸混合溶液作为电解液,温度为40~45℃,首先研究18CrNiMo7-6渗碳合金钢表层试样在不同抛光电压、抛光电流及抛光时间工艺参数下电解抛光后的表面质量,得到18CrNiMo7-6渗碳合金钢表层的最佳电解抛光参数为10 V、1.8~1.9 A、70 s;再对得到的表层最佳参数进行微调,得到不同渗碳深度下试样的最佳电解抛光参数,次表层电解抛光参数为10 V、1.6~1.7 A、65 s,心部电解抛光参数为10 V、1.5~1.6A、60 s。 展开更多
关键词 18CrNiMo7-6渗碳合金钢 电解抛光 最佳参数
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车削工艺参数对18CrNiMo7-6钢切削力及表面粗糙度的影响
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作者 朱浩阳 郜伟 +1 位作者 张银霞 刘治华 《工具技术》 北大核心 2024年第2期9-14,共6页
为了探究车削工艺参数对18CrNiMo7-6钢标准疲劳试样不同位置的切削力和表面粗糙度的影响,采用CAK4085型数控车床对主轴转速n、背吃刀量a_(p)和进给速度v_(f)三个工艺参数进行单因素试验研究。结果表明:对于标准试样的圆弧段和标距段,切... 为了探究车削工艺参数对18CrNiMo7-6钢标准疲劳试样不同位置的切削力和表面粗糙度的影响,采用CAK4085型数控车床对主轴转速n、背吃刀量a_(p)和进给速度v_(f)三个工艺参数进行单因素试验研究。结果表明:对于标准试样的圆弧段和标距段,切削用量对切削力和表面粗糙度的影响规律相同;背吃刀量a_(p)对切削力影响最大,进给速度v_(f)对切削力的影响次之,主轴转速n对切削力的影响最小;拟合的三个切削力分量指数公式中,主切削力的拟合误差为5.25%,背向力的拟合误差为2.29%,相对误差较小。结果显示,影响表面粗糙度Ra的最大因素为进给速度,Ra随v_(f)的增大而增大,圆弧切入段的表面粗糙度Ra比切出段高。综合考虑疲劳试样较好的加工工艺参数为:n=1000r/min,v_(f)=80mm/min,a_(p)=0.3mm。本研究结果可为疲劳试样的车削加工工艺制定提供参考依据。 展开更多
关键词 车削加工 切削力 表面粗糙度 车削工艺 18CrNiMo7-6
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渗碳工艺对18CrNiMo7-6合金钢缺口件疲劳性能的影响 被引量:1
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作者 秦盛伟 邸黎寅 +1 位作者 王连翔 张承昊 《材料导报》 EI CSCD 北大核心 2024年第2期200-206,共7页
为分析渗碳工艺对18CrNiMo7-6缺口构件疲劳性能的影响,对应力集中系数Kt=1.86的缺口试样进行渗碳热处理并测定其旋转弯曲疲劳性能,同时对试样表层组织、硬度以及应力场进行了表征。结果表明,渗碳热处理可以明显提升试样表面硬度并引入... 为分析渗碳工艺对18CrNiMo7-6缺口构件疲劳性能的影响,对应力集中系数Kt=1.86的缺口试样进行渗碳热处理并测定其旋转弯曲疲劳性能,同时对试样表层组织、硬度以及应力场进行了表征。结果表明,渗碳热处理可以明显提升试样表面硬度并引入残余压应力,并且可以显著提升缺口试样的疲劳性能,相较于未渗碳试样疲劳极限提升超过100%;随着有效硬化层深度的增加,缺口试样的疲劳极限均呈现先增后减的趋势。未渗碳试样和渗碳试样的疲劳源均在缺口根部表面处,且均为多源断裂。疲劳过程中渗碳试样表面残余奥氏体在循环应力作用下诱导马氏体相变,其转变量存在一个临界值。 展开更多
关键词 18CrNiMo7-6合金钢 应力集中 渗碳热处理工艺 高周疲劳性能
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