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THE INTRINSIC ACIDITY CONSTANTS AND SPECIFIC SURFACE AREA OF MARINE SOLID PARTICLES II. THE RELATIONSHIP BETWEEN THE INTRINSIC ACIDITY CONSTANT AND THE TERNARY SURFACE COMPLEX
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作者 王修林 张正斌 刘莲生 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1992年第1期68-74,共7页
This paper deals with the infrared spectra of " amino acid- clay , calcium carbonate and y-AlOOH" and " Cu (II )-clay-amino acid" model systems, and shows that the model of the ternary surface comp... This paper deals with the infrared spectra of " amino acid- clay , calcium carbonate and y-AlOOH" and " Cu (II )-clay-amino acid" model systems, and shows that the model of the ternary surface complex is M-OHLCu (L = amino acid) for marine solid particle-Cu (II)-amino acid. Study of the formation mechanism of the ternary surface complex shows that the specific surface area , and especially the intrinsic acidity constant, determine whether the ternary surface complex is easily formed, and that factor, FTSC,quantifies the relationship between the promoting effect of organics on Mt-marine solid particle ion exchange and the intrinsic acidity constant and specific surface area. 展开更多
关键词 INTRINSIC acidity CONSTANT TERNARY surface complex
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Syntheses,structures,and catalytic performances of complexes with 4,4'-dihydroxy-[1,1'-biphenyl]-3,3'-dicarboxylic acid ligands
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作者 LING Weizhong LIN Jingyi +3 位作者 ZHU Jianglin LIANG Yuyi DAI Shanshan LI Yu 《无机化学学报》 北大核心 2026年第1期152-160,共9页
Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(... Three copper(Ⅱ),nickel and cadmium(Ⅱ)complexes,namely[Cu_(2)(μ-H2dbda)2(phen)2]·2H_(2)O(1),[Ni(μ-H2dbda)(μ-bpb)(H_(2)O)2]n(2),and[Cd(μ-H2dbda)(μ-bpa)]n(3),have been constructed hydrothermally using H4dbda(4,4'-dihydroxy-[1,1'-biphenyl]-3,3'-dicarboxylic acid),phen(1,10-phenanthroline),bpb(1,4-bis(pyrid-4-yl)benzene),bpa(bis(4-pyridyl)amine),and copper,nickel and cadmium chlorides at 160℃.The products were isolated as stable crystalline solids and were characterized by IR spectra,elemental analyses,thermogravimetric analyses,and singlecrystal X-ray diffraction analyses.Single-crystal X-ray diffraction analyses revealed that three complexes crystallize in the monoclinic P21/n,tetragonal I42d,and orthorhombic P21212 space groups.The complexes exhibit molecular dimers(1)or 2D metal-organic networks(2 and 3).The catalytic performances in the Knoevenagel reaction of these complexes were investigated.Complex 1 exhibits an effective catalytic activity and excellent reusability as a heterogeneous catalyst in the Knoevenagel reaction at room temperature.CCDC:2463800,1;2463801,2;2463802,3. 展开更多
关键词 complex dicarboxylic acid catalytic properties Knoevenagel reaction
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Syntheses,crystal structures,catalytic and anti-wear properties of zinc(Ⅱ),nickel(Ⅱ)and cadmium(Ⅱ)complexes constructed from a terphenyl-tricarboxylate ligand
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作者 ZHAO Zhenghua LIU Yufeng +2 位作者 ZHANG Qing SHI Zifa GU Jinzhong 《无机化学学报》 北大核心 2026年第1期170-180,共11页
Three zinc(Ⅱ),nickel(Ⅱ),and cadmium(Ⅱ)complexes,namely[Zn(μ-Htpta)(py)_(2)]n(1),[Ni(H_(2)biim)2(H_(2)O)2][Ni(tpta)(H_(2)biim)2(H_(2)O)]2·3H_(2)O(2),and[Cd_(3)(μ4-tpta)2(μ-dpe)_(3)]_(n)(3),have been construc... Three zinc(Ⅱ),nickel(Ⅱ),and cadmium(Ⅱ)complexes,namely[Zn(μ-Htpta)(py)_(2)]n(1),[Ni(H_(2)biim)2(H_(2)O)2][Ni(tpta)(H_(2)biim)2(H_(2)O)]2·3H_(2)O(2),and[Cd_(3)(μ4-tpta)2(μ-dpe)_(3)]_(n)(3),have been constructed hydrothermally at 160℃ using H_(3)tpta([1,1':3',1″-terphenyl]-4,4',5'-tricarboxylic acid),py(pyridine),H_(2)biim(2,2'-biimidazole),dpe(1,2-di(4-pyridyl)ethylene),and zinc,nickel and cadmium chlorides,resulting in the formation of stable crystalline solids which were subsequently analyzed using infrared spectroscopy,element analysis,thermogravimetric analysis,as well as structural analyses conducted via single-crystal X-ray diffraction.The findings from these single-crystal Xray diffraction studies indicate that complexes 1-3 form crystals within the monoclinic system P2_(1)/c space group(1)or triclinic system P1 space group(2 and 3),and possess 1D,0D,and 3D structures,respectively.Complex 1 demonstrated substantial catalytic efficiency and excellent reusability as a heterogeneous catalyst in the reaction of Knoevenagel condensation under ambient temperature conditions.In addition,complex 1 also showcased notable anti-wear performance when used in polyalphaolefin synthetic lubricants.CCDC:2449810,1;2449811,2;2449812,3. 展开更多
关键词 complexES tricarboxylic acid catalytic properties Knoevenagel condensation reaction anti-wear performance
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Enhanced separation of yttrium,erbium and thulium with P507 induced by complexation kinetics of DTPA
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作者 Na SUI Shu-kai MIAO +3 位作者 Hao SHEN Kai-hui CUI Jia-qi WANG Kun HUANG 《Transactions of Nonferrous Metals Society of China》 2025年第4期1338-1349,共12页
Based on a non-equilibrium kinetic extraction technique,the complexation kinetics of diethylenetriamine-pentaacetic acid(DTPA)with rare earth(RE)ions was investigated with different adding sequences of DTPA.The result... Based on a non-equilibrium kinetic extraction technique,the complexation kinetics of diethylenetriamine-pentaacetic acid(DTPA)with rare earth(RE)ions was investigated with different adding sequences of DTPA.The results indicated that the separation factors ofβTm/Er andβY/Er were higher when adding DTPA at the start of extraction than those before extraction.The extraction order for Y,Er and Tm was Tm>Y>Er.The root of discrepancy in complexation kinetics of Y,Er and Tm ions with DTPA and the enhanced kinetic separation mechanism were elucidated from the forward complex formation and reverse dissociation rates by the stopped-flow spectrophotometric technique.The apparent complexation rate constants began to decrease gradually with the increase of aqueous pH,while increased with increasing DTPA concentration.The emergence of extraction priority order as Tm>Y>Er was verified according to the calculated reaction kinetic constants of Y,Er and Tm at different pH values. 展开更多
关键词 rare earths extraction complexation kinetics diethylenetriaminepentaacetic acid(DTPA) stopped-flow spectrophotometric technique
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Characteristics of Soluble and Exchangeable Acidity inan Extremely Acidified Acid Sulfate Soil 被引量:4
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作者 C.Lin M.D.MELVILLE 《Pedosphere》 SCIE CAS CSCD 1999年第4期323-330,共8页
An extremely acidified acid sulfate soil (ASS) was investigated to characterize its soluble and exchangeableacidity. The results showed that soluble acidity of a sample determined by titration with a KOH solutionwas m... An extremely acidified acid sulfate soil (ASS) was investigated to characterize its soluble and exchangeableacidity. The results showed that soluble acidity of a sample determined by titration with a KOH solutionwas much significantly greater than that indicated by pH measured using a PH meter, particularly for theextremely acidic soil samples. This is because the total soluble acidity of the extremely acidic soil sampleswas mainly composed of various soluble Al and Fe species, possibly in forms of Al sulfate complexes (e.g.,AISO4) and ferrous Fe (Fe2+). It is therefore suggested not to use pH alone as an indicator of soluble acidityin ASS, particularly for extremely acidic ASS. It is also likely that AISO4+ actively pericipated in cationexchange reactions. It appears that the possible involvement of this Al sulfate canon in the canon adsorptionhas significant effect on increasing the amount of acidity being adsorbed by the soils. 展开更多
关键词 acid sulfate soils aluminium sulfate complex exchangeable acidity HYDROLYSIS soluble acidity
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Effects of Oleanolic Acid on the Immune Complex Allergic Reaction and Inflammation
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作者 周重楚 孙晓波 +3 位作者 刘威 高洪波 师海波 苗艳波 《Journal of Chinese Pharmaceutical Sciences》 CAS 1993年第1期69-79,共11页
When oleanolic acid (OA) was administered ig before and after sensitization on d 1 to d 5 and d 11 to d 17,it had no apparent effect on Arthus reaction.When it was administered at 48,24 and 1 h before challenge,howeve... When oleanolic acid (OA) was administered ig before and after sensitization on d 1 to d 5 and d 11 to d 17,it had no apparent effect on Arthus reaction.When it was administered at 48,24 and 1 h before challenge,however,Arthus reaction was significantly inhibited.OA showed markedly suppressive effects on reversible passive Arthus reaction and leukocyte migratory response.It could significantly stabilize erythrocyte membrane,inhibit the swelling of the rat's hind paw induced by in- jecting mycostatin,reduce the acid phosphatase content in the inflammatory exudate,suppress the syn- thesis or release of PGE,histamine,LTB4 and kinin,and the phlogistic action of PGE_2,histamine,5- HT and kinin.In addition,it could decrease the content of malonyldialdehyde (MDA) in hepatic tissue of alcohol-intoxicated mice,and increase the activity of catalase (CAT) in hepatic tissue of mice.OA had no apparent effect on the activity of super-oxide dismutase (SOD) in rat serum,on the content of immune complex in serum of rat with Arthus reaction,on the phagocytosis of monocytc-macrophage system,on the clearance of enzyme-containing immune complex by macrophage,or on the activity of total complement. 展开更多
关键词 Oleanolic acid Immune complex allergic reaction Anti-immune complex allergic reaction INFLAMMATION ANTI-INFLAMMATION
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Synthesis and Luminescence of Complexes Eu_x Y_(1-x)(phen)L_3 被引量:5
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作者 赵永亮 赵凤英 《Journal of Rare Earths》 SCIE EI CAS CSCD 2002年第5期427-429,共3页
A series of binuclear complexes with different molar ratio of europium to yttrium with cinnamic acid and o phenanthroline were synthesized in anhydrous alcohol. Elemental analysis shows that the composition of the co... A series of binuclear complexes with different molar ratio of europium to yttrium with cinnamic acid and o phenanthroline were synthesized in anhydrous alcohol. Elemental analysis shows that the composition of the complexes are Eu x Y 1- x (phen)L 3 (L: C 6H 5CH=CHCOO, x =1.0, 0.7, 0.5, 0.3 and 0.1). The IR absorption spectra indicate that cinnamate is coordinated to the rare earth ions and chemical bonds are formed between rare earth ions and nitrogen atoms of o phenanthroline. Fluorescent spectra show that the emission of Eu 3+ ion can be greatly enhanced if some of europium ions in the complexes are substituted by yttrium ions. 展开更多
关键词 rare earths europium complex yttrium complex cinnamic acid o phenanthroline
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A Series of Mononuclear Complexes Constructed from Transition Metals and Amino Acid Derived Ligands: Syntheses, Structures and Photoluminescence 被引量:6
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作者 李新发 曹荣 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第11期1439-1447,共9页
Eight neutral mononuclear complexes constructed from transition metals (M = Co(Ⅱ), Ni(Ⅱ), Cu(Ⅱ), Zn(Ⅱ), Cd(Ⅱ)) and ligands N-(2-pyridylmethyl)-L-phenylalanine (L-Hpmpa) and N-(2-pyridylmethyl)-L... Eight neutral mononuclear complexes constructed from transition metals (M = Co(Ⅱ), Ni(Ⅱ), Cu(Ⅱ), Zn(Ⅱ), Cd(Ⅱ)) and ligands N-(2-pyridylmethyl)-L-phenylalanine (L-Hpmpa) and N-(2-pyridylmethyl)-L-tyrosine (L-Hpmtyr) have been synthesized by both hydrothermal and conventional room temperature reactions. Four of them have been structurally characterized by single-crystal X-ray diffractions. They are: [Co(L-pmpa)2·2H2O] 1, [Ni(L-pmpa)2·2H2O] 2, [Cu(L-pmpa)2·2H2O] 3 and [Cu(L-pmtyr)2·2H2O] 4. Single-crystal X-ray analysis, IR and elemental analysis revealed that complexes 1, 2 and 3 are isostructural. Powder X-ray diffraction, IR and elemental analysis revealed that complexes 4, 5 (Zn[L-pmtyr]2·2H2O), 6 (Cd[L-pmtyr]2·2H2O), 7 (Co[L-pmtyr]2·2H2O) and 8 (Ni[L-pmtyr]2·2H2O) are isostructural. The photoluminescence properties of L-Hpmtyr ligand, compounds 5 and 6 were also investigated. 展开更多
关键词 amino acid zinc complex cadmium complex PHOTOLUMINESCENCE
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Synthesis,Characterization and Fluorescence Properties of Europium,Terbium Complexes with Biphenyl-4-Carboxylic Acid and o-Phenanthroline 被引量:4
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作者 赵永亮 赵凤英 +1 位作者 李强 高德青 《Journal of Rare Earths》 SCIE EI CAS CSCD 2006年第z2期18-22,共5页
Two series of solid complexes of europium and terbium with biphenyl 4-carboxylic acid and phen were synthesized and characterized in this report. Their elemental analysis, molar conductivities and TG-DTA studies indic... Two series of solid complexes of europium and terbium with biphenyl 4-carboxylic acid and phen were synthesized and characterized in this report. Their elemental analysis, molar conductivities and TG-DTA studies indicate that the complexes have the composition of Eu(phen)L3·1/2H2O, Eu0.5RE0.5(phen) L3·1/2H2O; Tb (phen) L3·H2O and Tb0.5 RE0.5(Phen)L3·1/2H2O. (RE = Y3+, La3+ and Gd3+; L = biphenyl 4-carboxylic acid; phen = o-Phenanthroline). The studies of their IR, UV 1H NMR and molar conductivities demonstrate that biphenyl 4-carboylic acid is bounded with RE (III ) ion. Rare earth ions coordinate with two nitrogen atoms of phen molecules directly in these rare earth complexes. The fluorescence spectra and fluorescence lifetimes of the rare earth complexes show that the fluorescent intensity and lifetime of a series of europium complexes are longer than those of the series of terbium complexes as having the some ligands. There are better fluorescent intensity and lifetime of hetero-nuclear rare earth complexes than homo-nuclear rare earth complexes for europium complexes. The fluorescence emission intensity of Eu3 + is raised by inert fluorescent rare earth ions (Y3+ , Gd3+ and La3+ ), but in Tb3+ hetero-nuclear rare earth complexes the intensity of Tb3+ ions are quenched by the inert fluorescent rare earth ions. 展开更多
关键词 biphenyl 4-carboxlic acid O-PHENANTHROLINE europium complex terbium complex rare earths
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Syntheses, Structures and Photoluminescence of the Cadmium(Ⅱ) and Copper(Ⅱ) Complexes Based on 4'-(4''-Pyridyl)-2,2':6',2''-terpyridine and 1,4-Benzenedicarboxylic Acid Ligands 被引量:3
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作者 张兴晶 王璐瑶 +2 位作者 尉兵 张文通 车广波 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第7期1069-1079,共11页
Two new metal-organic complexes [Cd2(1,4-BDC)(4-pytyp)(H2O)4]·(1,4-BDC)(1) and [Cu2(1,4-BDC)(4-pytyp)2(H2O)2]·(1,4-BDC)·8H2O(2)(4-pytyp = 4'-(4''-pyridyl)-2,2':6',2''-terp... Two new metal-organic complexes [Cd2(1,4-BDC)(4-pytyp)(H2O)4]·(1,4-BDC)(1) and [Cu2(1,4-BDC)(4-pytyp)2(H2O)2]·(1,4-BDC)·8H2O(2)(4-pytyp = 4'-(4''-pyridyl)-2,2':6',2''-terpyridine, 1,4-H2 BDC = 1,4-benzenedicarboxylic acid) have been synthesized under hydrothermal conditions and characterized by elemental analysis, infrared analysis and X-ray single-crystal diffraction. The scrutiny of single-crystal structure reveals that complex 1 forms to a 3D supramolecular network linked by π-π stacking interactions and hydrogen bonds. X-ray diffraction analysis reveals that complex 2 exhibits a 3D supramolecular network linked through complicated hydrogen bonds. The thermogravimetric analysis and photoluminescent properties of 1 and 2 are discussed in detail. 展开更多
关键词 cadmium(Ⅱ) complex copper(Ⅱ) complex 4'-(4''-pyridyl)-2 2':6' 2''-terpyridine 1 4-benzenedicarboxylic acid crystal structure
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Synthesis and Fluorescence Properties of Europium, Terbium Doped Zn^(2+), Cd^(2+) and Cr^(3+) Complexes 被引量:1
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作者 温孝春 赵永亮 +2 位作者 王连蒙 张梅 高德青 《Journal of Rare Earths》 SCIE EI CAS CSCD 2007年第6期679-683,共5页
Europium and terbium complexes with strong fluorescence intensity and long fluorescence lifetime were prepared. By replacing half of the europium or terbium ion with M (M = Zn^2+, Cd^2+, and Cr^3+) using the dope... Europium and terbium complexes with strong fluorescence intensity and long fluorescence lifetime were prepared. By replacing half of the europium or terbium ion with M (M = Zn^2+, Cd^2+, and Cr^3+) using the doped method, and then incorporating it with 18-crown-6 ether and terephthalic acid, six heteronuclear samples EuZnLL'Cl3·3H2O(1), EuCdLL2'Cl3·5H2O(2), EuCrLL'Cl4· 4H2O(3), TbZnLL'Cl3·4H2O(4), TbCdLL'2Cl3·4H2O(5), and TbCrLL'2Cl4 ·4H2O(6) (L = terephthalic acid, L'= 18-Crown-6 ether) were obtained. The elemental analysis, molar conductivities, rare earth complexometry, Fourier Transform Infrared Spectroscopy (FT-IR), ultraviolet (UV), TGA, fluorescence intensity, and fluorescence lifetime of the samples were measured. The results showed that there were good luminescence properties for heteronuclear complexes (1), (2), (4), and (5), which were even stronger than those of the homonuclear complexes Eu2LL'2Cl4·4H2O and Tb2LL'2Cl4 ·4H2O, but the luminescence properties of EuCrLL'Cl4·4H2O, TbCrLL'Cl4·4H2O were very weak. A possible luminescence mechanism was suggested by the organic-inorganic doped mechanism and the law of intramolecular energy transfer. 展开更多
关键词 europium complex terbium complex terephthalie acid crown ether rare earths
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Two Three-dimensional Supramolecular Complexes Assembled by 2-Chlorinebenzoic Acid and Bis(imidazol)Ligands:Syntheses,Structures and Fluorescent Properties 被引量:2
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作者 刘博 吕丛 +3 位作者 李秀梅 潘亚茹 车广波 周实 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2018年第11期1821-1828,共8页
Two new three-dimensional supramolecular complexes, namely, [Cd(cba)2(bib)]n(1) and [Zn(cba)2(bib)]2 n(2)(Hcba = 2-chlorinebenzoic acid, bib = 1,4-bis(imidazol-1-yl)-butane)were hydrothermally designed and synthesized... Two new three-dimensional supramolecular complexes, namely, [Cd(cba)2(bib)]n(1) and [Zn(cba)2(bib)]2 n(2)(Hcba = 2-chlorinebenzoic acid, bib = 1,4-bis(imidazol-1-yl)-butane)were hydrothermally designed and synthesized. Their structures were determined by elemental analyses, IR spectroscopy, TG, fluorescence spectroscopy, single-crystal and powder X-ray diffraction. Complex 1 exhibits a one-dimensional zigzag chain and complex 2 shows a zero-dimensional structure, which were further extended into three-dimensional supramolecular structures through hydrogen bonds and π-π stacking interactions. 展开更多
关键词 crystal structure Cd(Ⅱ) complex Zn(Ⅱ) complex 2-chlorinebenzoic acid 1 4-bis(imidazol-1-yl)-butane
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Study on Copolymerization of Rare Earth-Carboxylic Acid Complex 被引量:1
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作者 邱关明 张明 +3 位作者 严长浩 周兰香 戴少俊 Okamo to Hiroshi 《Journal of Rare Earths》 SCIE EI CAS CSCD 2003年第6期618-621,共4页
Complex of rare earth with carboxylic acid was prepared by precipitation and direct method. It was copolymerized with such monomers as acrylic acid and other ones to synthesize ionomer of rare earth and organic polyme... Complex of rare earth with carboxylic acid was prepared by precipitation and direct method. It was copolymerized with such monomers as acrylic acid and other ones to synthesize ionomer of rare earth and organic polymer with different rare earth contents. Its glass-transition temperature and heat stability were analyzed by TG and DTA. Infra-red detector was used to show its structure. The effect of rare earth complex prepared by different methods on copolymerization and properties of copolymers was also discussed. 展开更多
关键词 organic material rare earth ionomer COPOLYMERIZATION rare earth complex monomer rare earth-carboxylic acid complex rare earths
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Cu(Ⅱ),Ni(Ⅱ)Complexation with Acid Alizarine Blue B in the Presence of Cetyltrimethylammonium Bromide
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作者 沈荣 郜洪文 俞汉青 《Chinese Journal of Chemical Physics》 SCIE CAS CSCD 北大核心 2006年第2期178-182,共5页
The coordination reactions of Cu(Ⅱ) and Ni(Ⅱ) with acid alizarine blue B (AABB) in the presence of cetyltrimethylammonium bromide (CTAB) micelle were investigated using the microsurface adsorptionspectral co... The coordination reactions of Cu(Ⅱ) and Ni(Ⅱ) with acid alizarine blue B (AABB) in the presence of cetyltrimethylammonium bromide (CTAB) micelle were investigated using the microsurface adsorptionspectral correction technique (MSASC). The aggregation of AABB on CTAB followed the Langmuir isothermal adsorption law. The enrichment of AABB on CTAB sensitized the complexation between Cu(Ⅱ) or Ni(Ⅱ)and AABB. The binding ratio of AABB to CTAB was 1:2.5, and monomeric aggregate, AABB2CTAB5, was formed with an adsorption constant of 5.95×10^5 at 20 ℃ or 2.48×10^5 at 40 ℃. In the ternary complexation, the ratio of AABB:Cu and AABB:Ni were 1:1 and 1:2.5, respectively. Two types of aggregates, Cu2.AABB2·CTAB80 and Ni5.AABB2.CTAB80, were formed. 展开更多
关键词 Microsurface adsorption-spectral correction technique Langmuir aggregation Acid alizarine blue B Cetyltrimethylammonium bromide Ternary complex
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N,O-Bidentated difluoroboron complexes based on pyridine-ester enolates:Facile synthesis,post-complexation modification,optical properties,and applications 被引量:1
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作者 Chaochao Jin Kai Li +2 位作者 Jiongpei Zhang Zhihua Wang Jiajing Tan 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第9期169-174,共6页
An array of pyridine-ester enolate based organoboron complexes has been designed and synthesized via a one-pot cascade of Pd-catalyzedα-arylation and BF2complexation.The rapid structure-activity relationship(SAR)stud... An array of pyridine-ester enolate based organoboron complexes has been designed and synthesized via a one-pot cascade of Pd-catalyzedα-arylation and BF2complexation.The rapid structure-activity relationship(SAR)studies indicated that unsymmetrical N,O-chelated BF2complexes were highly fluorescent in solid state,and exhibited large Stokes shifts,excellent photostability,along with insensitivity to p H.Theα-aryl group could not only modulate the electronic effect but also inhibit the intermolecularπ-πstacking to promote the aggregation-induced emission(AIE)effect.DFT calculations and experiments identified that the intramolecular charge transfer properties of these N,O-chelates could be switched by the modification of substituents,resulting tunable fluorescence wavelengths.Furthermore,post-complexation modification was accomplished,including Suzuki-Miyaura cross-coupling,Buchwald-Hartwig amination,oxidative cleavage,along with a unique triple substitution reaction involving propargyl Grignard reagents.The exemplificative application of dimethylamine substituted boron complex as a reversible acidic vapor sensor was also demonstrated. 展开更多
关键词 N O-Bidentate BF2 complexes Aggregation-induced emission Large Stokes shift Post-complexation modification Reversible acidic vapor sensor
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Concentration of linoleic acid from cottonseed oil by starch complexation
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作者 Dan Liang Yufeng Hu +4 位作者 Weiting Ma Zhengtang Zhao Siqi Jiang Yichuan Wang Xianming Zhang 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2019年第4期845-849,共5页
The extraction of linoleic acid from fatty acids(FA) of the cottonseed oil using starch–FA complexes was developed for the first time. We showed that starch can form inclusion complexes of different strengths with FA... The extraction of linoleic acid from fatty acids(FA) of the cottonseed oil using starch–FA complexes was developed for the first time. We showed that starch can form inclusion complexes of different strengths with FA and that the different strengths stem from the differences in chain length, degree of unsaturation, and position of double bonds of FA. The optimal separation conditions were determined as follows: The inclusion temperature is 69 °C, the inclusion time is 30 min, the starch/FA mass ratio is 10:1, and the ratio of the volume of methanol–water solution and the mass of FA is 18:1. Compared to urea inclusion complexation, starch complexation has milder reaction temperature and shorter reaction time. Under these conditions, linoleic acid can be concentrated from 38.9% to 70.04% by one-off extraction. Moreover, the experimental results demonstrate the almost perfect reusability of starch. These results show that starch complexation is a promising method that can be used to obtain highly concentrated linoleic acid from cottonseed oil. 展开更多
关键词 STARCH Linoleic ACID STARCH complexATION Starch–FA complex COTTONSEED oil
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Crystal Structure of a Novel Sandwich Inclusion Complex of β-Cyclodextrin with α-Naphthylacetic Acid
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作者 WANG En-ju CHEN Guang-ying HAN Chang-ri 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2011年第5期730-733,共4页
A supramolecular inclusion complex between β-cyclodextrin(β-CD) and α-naphthylacetic acid was prepared, and its crystal structure was investigated by single-crystal X-ray crystallography. The complex contains two... A supramolecular inclusion complex between β-cyclodextrin(β-CD) and α-naphthylacetic acid was prepared, and its crystal structure was investigated by single-crystal X-ray crystallography. The complex contains two β-CD molecules, one α-naphthylacetic acid, two ethanols and twenty-eight water molecules in the asymmetric unit, which could be formulated as [(C42H70O35)2·(C12H10O2)·(C2H5OH)2·28H2O]. Two β-CD molecules constitute a dimer by face-to-face contact of their secondary hydroxyl sides. At the interface of the dimer, one α-naphthylacetic acid molecule is sandwiched between two β-CD molecules. Each β-CD unit of the dimer includes one ethanol molecule in its cavity. The β-CD dimers are linked together via hydrogen bonding to form layers that are stacked in a brickwork-like pattern. The comparative study of some sandwich complexes elucidates that the interface of the β-CD dimer has a stronger inclusion capacity than the cavity of β-CD for some suitable planar vip molecules. The novel inclusion structure results from the competitive inclusion of α-naphthylacetic acid and ethanol. 展开更多
关键词 Β-CYCLODEXTRIN α-Naphthylacetic acid Inclusion complex Sandwich complex Competitive inclusion
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Stability on the ^(109)Cd,^(65)Zn Complex with Humus Acids
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作者 HUA Luo, CHEN Shi-bao, BAI Ling-yu and WEI Dong-pu( Geology Department, Capital Normal University, Beijing 100037 , P.R.China Institute for Application of Atomic Energy, Chinese Academy of Agricultural Sciences , Beijing 100094 ,P.R. China ) 《Agricultural Sciences in China》 CAS CSCD 2002年第5期520-525,共6页
The radioactive isotope tracer and ion exchange balanced method was used to study the stability of 109Cd, 65 Zn complexes with humus acids. In the 109Cd and 65 Zn single existing system with humic acids, the stability... The radioactive isotope tracer and ion exchange balanced method was used to study the stability of 109Cd, 65 Zn complexes with humus acids. In the 109Cd and 65 Zn single existing system with humic acids, the stability constants of the humic-109Cd(65Zn) complex compound was higher than the fulvic-109 Cd(65Zn) complex compound. The stability constant of the humic (fulvic) -65Zn was higher than that of the humic (ful-vic)-109Cd. In the 109Cd and 65 Zn coexisting system, the stability constant and the co-ordination number of the humic (fulvic)-65Zn complex obviously increased, but the stability constant and the co-ordination number of the humic (fulvic)-109Cd complex obviously decreased as compared with its respectively single existing system . The result showed that the humus matter with higher molecular weight could more effectively reduce plant availability of heavy metals than that with lower molecular weight in polluted soil by heavy metals. The humus matter could more effectively reduce plant availability of Zn than that of Cd. Application of humus-acid increased the harm of Cd and decreased the harm of Zn to plants in Cd-Zn coexisting system. 展开更多
关键词 Humus acid complex CADMIUM ZINC Stability of complex Isotope tracer technique
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Syntheses and Magnetism of μ-1, 3, 5-Benzenetricarboxylato Trinuclear Manganese(Ⅱ) and Nickel(Ⅱ)Complexes
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作者 SHI Jing-min LIAO Dai-zheng +2 位作者 CHENG Peng JIANG Zong-hui MIAO Ming-ming and WANG Geng-lin. (Department of Chemistry, Nankai University, Tianjin, 300071 ) 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1996年第1期1-5,共5页
Two new manganese(Ⅱ ) trinuclear complexes and two new nickel (Ⅱ) trinuclear compIexes, namely, [Mn3 (BZT ) (Phen )6] (ClO4 )3 (complex 1 ), [Mn (BZT)· (Nphen )6] (ClO4 )3 (complex 2), [Ni3 (BZT) (Phen)6] (ClO4... Two new manganese(Ⅱ ) trinuclear complexes and two new nickel (Ⅱ) trinuclear compIexes, namely, [Mn3 (BZT ) (Phen )6] (ClO4 )3 (complex 1 ), [Mn (BZT)· (Nphen )6] (ClO4 )3 (complex 2), [Ni3 (BZT) (Phen)6] (ClO4 )3· 5H2O (complex3) and [Ni3 (BZT ) (Nphen )6] (ClO4 )3 (complex 4 ) (BZT = 1, 3, 5-benzenetricarboxylato, Phen = 1, 10-phenthroline, Nphen = 5-nitro-1, 10-phenanthroline )have been synthesized. The complexes were characterized using elemental analysis,IR and electronic reflection spectra. These complexes are proposed to have extended 1, 3, 5-benzenetricarboxylato-bridged structure and to consist of three manganese (Ⅱ) or three nickel(Ⅱ). The X-band ESR spectra of the complex 1 and complex 2were recorded at room temperature. The variable-temperature magnetic susceptibilities of complex 1 and complex 3 were measured over 4. 2-300 K. According to experimental results of the variable-temperature magnetic susceptibility, the magnetic interaction between the paramagnetic centers is too weak to be detected using the usual magnetic susceptibility technique. 展开更多
关键词 Manganese (Ⅱ) complex Nickel (Ⅱ) complex 1 3 5-benzenetricarboxylic acid MAGNETISM
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Syntheses aod Crystal Structures of Rare Earth Complexes with Adamantanecarboxylic Acid, [LnL_3(HL)(H_2O)]_2·2EtOH·2H_2O (Ln=Nd (1), La (2))
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作者 Zhu Zhili Feng Yunlong Lin Hong 《Journal of Rare Earths》 SCIE EI CAS CSCD 2005年第5期647-647,共1页
The title complexes (LnL3 (HL) (H2O) ]2· 2EtOH·2H2O (Ln= Nd (1), La (2), HL=adamantanecarboxylic acid) were prepared and determined by single-crystal X-ray diffraction. Both complexes crystallize ... The title complexes (LnL3 (HL) (H2O) ]2· 2EtOH·2H2O (Ln= Nd (1), La (2), HL=adamantanecarboxylic acid) were prepared and determined by single-crystal X-ray diffraction. Both complexes crystallize in triclinic system with space group P 1^-, cell parameters are: complex (1) a = 1.0556(2) nm, b =1.4913(3) nm, c = 1.4920(3) nm, a = 106.26 (3)°, β=93.51(3)°, γ=97.23(3)°, V=2.2253 (5) nm^3, Dcal=1.409 g · cm^-3, Z = I , F ( 000 ) = 990, μ(Mo Kα) = 1. 225 mm^-1, M, = 1884.50; complex (2) a = 1.0453(2) nm, b = 1.4971(3)nm, c = 1.5052(3) nm, α = 106.07(3)°, β =93.58 (3)°, γ=97.56(3)°, V=2.2391(5)nm^3, Dcal= 1.397 g·cm^-3, Z = 1, F(000) =984, μ(Mo Kα) = 1.015 mm^-1, Mr= 1877.88. The final R and wR are 0. 0396 and 0. 1062 for 8589 (1 ≥ 2σ (I)) observed reflections for complex (1), 0.0505 and 0. 1344 for 8417 ( 1 ≥ 2σ (1) ) observed reflections for complex (2), respectively. The crystals are consisted of a binuelear molecule. The coordination geometry of the Ln( Ⅲ ) ion can be described as trieapped trigonal prism. 展开更多
关键词 Nd( Ⅲ) complex Nd( complex adamantanecarboxylic acid crystal structure rare earths
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