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Preparation and Properties of HBS Lignin from Masson Pine 被引量:23
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作者 CHENGXian-su CHENWei-jian +3 位作者 CHENYun-ping CHENYue-xian LIMian-jun FANGHua-shu 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第2期225-228,共4页
In order to establish a new method for making cellulose and lignin from Masson pine, a high boiling solvent(HBS) pulping process with an aqueous solvent of 1,4-butanediol was investigated. Masson pine chips were pulpe... In order to establish a new method for making cellulose and lignin from Masson pine, a high boiling solvent(HBS) pulping process with an aqueous solvent of 1,4-butanediol was investigated. Masson pine chips were pulped with a 70%—90% aqueous solution of 1,4-butanediol containing a small amount of a catalyst at 200—220 ℃ for 60—180 min. HBS Masson pine cellulose is suitable for making paper. Water-insoluble HBS lignin was separated from the liquor reaction mixture by water precipitation. The recovered high boiling solvent(RHBS) is able to be recycled as a pulping solvent, indicating that the HBS method is a pulping process of Masson pine which is energy saving, resources saving and pollution free. HBS lignin has a better chemical reactivity and a lower ash content than lignin sulfonate. 展开更多
关键词 High boiling solvent(HBS) Masson pine LIGNIN 1 4-BUTANEDIOL
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A NEW METHOD FOR MAKING CELLULOSE AND LIGNIN FROM BAMBOO BY HIGH BOILING SOLVENT 被引量:2
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作者 XiansuCHENG WeijianCHEN YunpingCHEN HuashuFANG MianjunLI YuexianCHEN 《天津科技大学学报》 CAS 2004年第A02期67-71,共5页
In order to establish a new method for making cellulose and lignin from bamboo, a high boiling solvent (HBS) pulping process with aqueous solvcnt of 1,4-butanediol was investigated. Bamboo chips were pulped with 70~9... In order to establish a new method for making cellulose and lignin from bamboo, a high boiling solvent (HBS) pulping process with aqueous solvcnt of 1,4-butanediol was investigated. Bamboo chips were pulped with 70~90% aqueous solution of 1. 4-butanediol containing a small amount of catalyst at 180~200℃ for 30~90 min. HBS bamboo cellulose is suitable for making paper. Water-insoluble HBS lignin was separated from the liquor reaction mixture by water precipitation. Recovery high boiling solvents (RHBS) is able to recycle as a pulping solvent indicating that the HBS method is a pulping process of bamboo with saving energy, saving resources and non-pollution. HBS lignin has better chemical activity and lower ash content than lignin sulfonate. 展开更多
关键词 竹子 高沸腾溶解 木质素 1 4-丁二醇 纤维素 造纸工业
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Two Cyclic Peptides Produced by the Endophytic Fungus # 2221 from Castaniopsis fissa on the South China Sea Coast 被引量:2
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作者 WenQingYIN JieMingZOU +3 位作者 ZhiGangSHE L.L.P.Vrijmoed E.B.GarethJones YongChengLIN 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第2期219-222,共4页
New cyclic peptides 1 and 2 were isolated from the endophytic fungus #2221 fromCastaniopsis fissa on the south China sea coast. By 2D NMR methods and chiral HPLC technique,their structures were elucidated as cyclo (L-... New cyclic peptides 1 and 2 were isolated from the endophytic fungus #2221 fromCastaniopsis fissa on the south China sea coast. By 2D NMR methods and chiral HPLC technique,their structures were elucidated as cyclo (L-Val-L-Leu-L-Val-L-Leu) and cyclo(L-Leu-L-Ala-L-Leu-L-Ala), respectively. 展开更多
关键词 Endophytic fungus cyclic peptides metabolite.
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A New Activation Method for Electroless Metal Plating: Palladium Laden via Bonding with Self-Assembly Monolayers 被引量:1
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作者 LiNaXU JianHuiLIAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2002年第7期687-688,共2页
A new activation method has been developed for electroless copper plating on silicon wafer based on palladium chemisorption on SAMs of APTS without SnCl2 sensitization and roughening condition. A closely packed elect... A new activation method has been developed for electroless copper plating on silicon wafer based on palladium chemisorption on SAMs of APTS without SnCl2 sensitization and roughening condition. A closely packed electroless copper film with strong adhesion is successfully formed by AFM observation. XPS study indicates that palladium chemisorption occurred via palladium chloride bonding to the pendant amino group of the SAMs. 展开更多
关键词 Palladium chemisorption amino group SAMS ACTIVATION electroless plating.
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Theoretical Study on the Structure and Isomerization of CH_3SB 被引量:1
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作者 杜玉扣 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第3期349-353,共5页
The structure and mechanism of isomerization of CH3SB have been studied by using DFT method at the B3LYP/6-311G** level. The computational results reveal that the energy of singlet state of CH3SB is lower than that ... The structure and mechanism of isomerization of CH3SB have been studied by using DFT method at the B3LYP/6-311G** level. The computational results reveal that the energy of singlet state of CH3SB is lower than that of triplet state, so the former should be the ground state. Two transition states of isomerization of singlet state of CH3SB have been determined at the B3L-YP/6- 311G** level, too. The methyl linked to sulfur atom is first transferring to the boron atom, to which the hydrogen atom of methyl is then transferring. According to the results of this paper, reaction paths of isomerizations of CH3SB are studied thoroughly with IRC method. 展开更多
关键词 DFT CH3SB singlet state ISOMERIZATION IRC
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Photopromoted Methoxycarbonylation of Olefins Under Ambient Conditions in DMF 被引量:1
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作者 WenHaoSUN JingMeiYIN +3 位作者 DaBinGAO GuangYunZHOU YingPingJIA XiangShengWANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第10期1245-1248,共4页
Photopromoted methoxycarbonylation of olefins with carbon monoxide can be carried out under ambient conditions with non-precious transition metal complexes (such as cobalt complexes) catalysts in DMF. The isotope expe... Photopromoted methoxycarbonylation of olefins with carbon monoxide can be carried out under ambient conditions with non-precious transition metal complexes (such as cobalt complexes) catalysts in DMF. The isotope experiments show that DMF is decomposed under irradiation and is conveniently used as a carbon monoxide source for the reaction. 展开更多
关键词 Photopromoted methoxycarbonylation carbon monoxide DMF isotope experiment.
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A Taxatetraene from Microbial Transformation of Sinenxan A 被引量:2
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作者 JunGuiDAI LinYANG +1 位作者 JunIchiSAKAI MasayoshiANDO 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第6期736-738,共3页
Sinenxan A [2α, 5α, 10β, 14β-tetraacetoxytaxa-4(20), 11-diene, 1] was biotransformed by a filamentous fungus, Aspergillus niger JCM 5546, and an unusual taxatetraene [2α, 5α-acetoxytaxa-4(20), 10(11), 12(18), 13... Sinenxan A [2α, 5α, 10β, 14β-tetraacetoxytaxa-4(20), 11-diene, 1] was biotransformed by a filamentous fungus, Aspergillus niger JCM 5546, and an unusual taxatetraene [2α, 5α-acetoxytaxa-4(20), 10(11), 12(18), 13(14)-tetraene, 2], together with two known products, 10β-deacetyl sinenxan A (3) and 10β, 14β-dideacetyl sinenxan A (4) were produced. 展开更多
关键词 Aspergillus niger sinenxan A taxatetraene biotransformation.
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Photopromoted Carbonylation of Alkyl Halides Under Ambient Conditions 被引量:1
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作者 YanSUN JingMeiYIN +2 位作者 DaBinGAO GuangYunZHOU YingPingJIA 《Chinese Chemical Letters》 SCIE CAS CSCD 2003年第6期575-578,共4页
Photopromoted carbonylation of alkyl halides with carbon monoxide can be carried out under ambient conditions with non-precious transition metal complexes (such as cobalt complexes) catalysts. Our preliminary work sh... Photopromoted carbonylation of alkyl halides with carbon monoxide can be carried out under ambient conditions with non-precious transition metal complexes (such as cobalt complexes) catalysts. Our preliminary work showed that alkyl halides can be transformed into alkene and alkane directly under irradiation, but the esters can not be transformed. It is assumed that the carbonylation of alkyl halides may be proceeded in two ways. 展开更多
关键词 Photopromoted carbonylation alkyl halides carbon monoxide.
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Kinetics and Mechanism of Exothermic First-stage Decomposition Reaction for 2,6-Dinitro-4,8- bis(2,2,2-trinitroethyl)-2,4,6,8-tetra- azabicyclo[3.3.1] nonane-3,7-dionel 被引量:1
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作者 HURong-zu YANGDe-suo +7 位作者 ZHAOFeng-qi CHENPei LUOYang CHENSan-ping ZHAOHong-an SONGJi-rong GAOSheng-li SHIQi-zhen 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 2004年第6期821-825,共5页
关键词 Decomposition 2 6-Dinitro-4 8- bis(2 2 2 -trinitroethyl)-2 4 6 8-tetraazabicyclo [3.3.1] nonane-3 7-dionel DSC Kinetics Mechanism TG
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Synthesis and Crystal Structure of Bis(tert-butyl-cyclopentadienyl)Erbium Ethoxide, (t-BuCp)_2ErOEt
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作者 罗云杰 姚英明 +1 位作者 沈琪 邢彦 《Journal of Rare Earths》 SCIE EI CAS CSCD 2002年第5期374-377,共4页
The formation of ( t BuCp) 2ErOEt was discussed. Its single crystal structure was determined by X ray diffraction. The crystal is monoclinic, P 2(1)/ c space group, a =1.0191(2), b =1.6203(5), c ... The formation of ( t BuCp) 2ErOEt was discussed. Its single crystal structure was determined by X ray diffraction. The crystal is monoclinic, P 2(1)/ c space group, a =1.0191(2), b =1.6203(5), c =1.2118(3) nm, β =102.960(10)°, V =1.9500 (nm 3), Z =2, D c=1.566 mg·m -3 , R =0.0450, R w=0.1363. The complex is monomeric and solvent free in the solid state. The erbium ion is coordinated by two tert butyl cyclopentadienyl rings and one oxygen atom of ethoxy group to form a seven coordinated complex. 展开更多
关键词 rare earths organolanthanide tert butyl cyclopentadienyl ERBIUM ethoxide X ray crystal structure
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Synthesis and Crystal Structure of N-phenylthiocyano-phenyl-thioformamide bis(η_5-methylcyclopentadienyl)(tetrahydrofuran)Samarium(Ⅲ)
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作者 李焕荣 姚英明 +2 位作者 沈琪 王璐 郁开北 《Journal of Rare Earths》 SCIE EI CAS CSCD 2002年第5期370-373,共4页
The insertion reaction of phenyl isothiocyanate into the Ln S bond was studied. Phenyl isothiocyanate reacted with [(CH 3C 5H 4) 2Sm(SPh)(THF)] 2 to give the title complex, (CH 3C 5H 4) 2Sm[SC(SPh)NPh](THF),... The insertion reaction of phenyl isothiocyanate into the Ln S bond was studied. Phenyl isothiocyanate reacted with [(CH 3C 5H 4) 2Sm(SPh)(THF)] 2 to give the title complex, (CH 3C 5H 4) 2Sm[SC(SPh)NPh](THF), in good yield, which was characterized by elemental analyses, IR, 1H NMR and X ray structural determination. The crystal structure analysis of complex shows that samarium atom is coordinated by two CH 3C 5H 4 groups, one O atom of THF, and N and S atoms from the SC(SPh)NPh ligand to form a distorted trigonal bipyramidal geometry. 展开更多
关键词 rare earths SAMARIUM thiolate complex insertion reaction phenyl isothiocyanate
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Selective Oxidation of Isobutane over NH_4CsFePVMoAs Heteropolycompound Catalysts
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作者 TiejunCai ZhengjunFang QianDeng ZhenshanPeng 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2005年第1期54-60,共7页
A series of NH_4Cs_(1.5)Fe_(0.08)H_xPVMo_(11)As_aO_y heteropolycompoundcatalysts for the selective oxidation of isobutane, having Keggin structure, were synthesized byusing co-precipitation method. The catalysts were ... A series of NH_4Cs_(1.5)Fe_(0.08)H_xPVMo_(11)As_aO_y heteropolycompoundcatalysts for the selective oxidation of isobutane, having Keggin structure, were synthesized byusing co-precipitation method. The catalysts were characterized by FT-IR, H_2-TPR, TG-DTA, SEM andXRD. Effects of the As content, reaction time, reaction temperature and molar ratio of isobutane tooxygen in feedstock on the activity and selectivity of the catalyst were investigated. Theactivation energy of the catalysts was measured by kinetics researches. Results showed theintroduction of Cs^+ into the catalysts shortened the stable period of them and enhanced theircatalytic activity for the selective oxidation of isobutane. The highest conversion of isobutane andthe total selectivity to liquid products were 18.6% and 81.2%, respectively, which were obtained at380℃ with a space velocity of 975 h^(-1) over the NH_4Cs_(1.5)Fe_(0.08)H_xPVMo_(11) As_(0.3)O_yheteropolycompound catalyst. It is confirmed that completely oxidized products were controlled well. 展开更多
关键词 heteropolycompound catalyst ISOBUTANE selective oxidation methacrylicacid METHACROLEIN
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A New Immunoassay Method by Capillary Electrophoresis with Enhanced Chemiluminescence Detection
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作者 JiaoNingWANG JiCunREN 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第6期793-796,共4页
This paper described a new immunoassay method by capillary electrophoresis with enhanced chemiluminescence (CL) detection system based on luminol-hydrogen peroxide reaction catalyzed by horseradish peroxides (HRP). Us... This paper described a new immunoassay method by capillary electrophoresis with enhanced chemiluminescence (CL) detection system based on luminol-hydrogen peroxide reaction catalyzed by horseradish peroxides (HRP). Using para-iodophenol as a CL enhancer, the detection limit of about 1×10-12 mol/L for HRP was achieved, which corresponded to 1.32×10-5 U/mL. In optimal conditions, the free HRP-labeled CA125 antibody (Ab*) and the bound enzyme-labeled complex (Ab*-Ag) were well separated by capillary electrophoresis within 4 min. The assay was successfully used to determine the contents of CA125 in human sera, which were associated with ovarian cancer, and the recoveries of the standard addition experiments were 96 to 109 %. 展开更多
关键词 Capillary electrophoresis chemiluminescence detection CA125 immunoassay.
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A New Diterpenoid Glucoside from Aster smithianus
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作者 ShouJunGUO XingHuaZHAO DongLiangCHENG 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第12期1451-1453,共3页
A new diterpenoid trisaccharide, smithoside A, was isolated from Aster smithianus. Itsstructure was identified as pimar-15 (16)-β-en-3β, 8β, 11α-triol-3-O-β-D-glucopyranosyl (1→3)-[β-glucopyranosyl (1→2)]-β-D... A new diterpenoid trisaccharide, smithoside A, was isolated from Aster smithianus. Itsstructure was identified as pimar-15 (16)-β-en-3β, 8β, 11α-triol-3-O-β-D-glucopyranosyl (1→3)-[β-glucopyranosyl (1→2)]-β-D-glucopyranoside on the basis of the spectral and chemical methods. 展开更多
关键词 Aster smithianus diterpenoid glucoside pimarene smithoside A.
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Synthesis of Chiral N-Ferrocenylmethylaminoalcohols and their Application in Enantioselective Addition of Diethylzinc to Aldehydes
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作者 JianFengGE ZongXuanSHEN YaWenZHANG 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第9期1025-1028,共4页
Three chiral N-ferrocenylmethylaminoalcohols were synthesized from readily available natural L-valine, leucine and phenylanine, and used as chiral ligands in the enantioselective addition of diethylzinc to aldehydes.
关键词 N-Ferrocenylmethylaminoalcohol asymmetric synthesis enantioselective addition DIETHYLZINC
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Synthesis and Crystal Structure of Lanthanide Schiff Base Complex [2-OC_6H_4CHN(2,6-i-Pr_2C_6H_3)]_2ErCl(THF)
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作者 YULong-Bao YAOYing-Ming +2 位作者 SHENQi ZHANGYong LANGJian-Ping 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2003年第5期517-520,共4页
The lanthanide Schiff base complex [2-OC6H4CHN(2,6-i-Pr2C6H3)]2ErCl(THF) (C42H52ClErN2O3) has been prepared by the reaction of anhydrous LnCl3 with 2 equiv. of the sodium salt of the bidentate Schiff base N-(2,6-diiso... The lanthanide Schiff base complex [2-OC6H4CHN(2,6-i-Pr2C6H3)]2ErCl(THF) (C42H52ClErN2O3) has been prepared by the reaction of anhydrous LnCl3 with 2 equiv. of the sodium salt of the bidentate Schiff base N-(2,6-diisopropylphenyl)salicylaldimine in THF. The crystal structure was determined by X-ray diffraction analysis. The crystal belongs to triclinic, space group P1 with a = 9.200(1), b = 13.637(2), c = 16.705(2) ? a = 74.493(7), b = 77.979(8), g = 81.306(8), V = 1965.2(4) ?, Z = 2, Mr = 835.60, Dc = 1.412 g/cm3, F(000) = 854, T = 193 K, l(MoKa) = 0.7107 ?and m = 22.38 cm-1. The final R = 0.052 and wR = 0.076 for 8386 observed reflections with I ≥ 2s(I). 展开更多
关键词 Schiff base lanthanide complex synthesis crystal structure
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Synthesis and Crystal Structure of Dicyanamide (5,7,7,12,14,14-Hexamethyl-1,4,8,11-tetraazacyclo- tetradecane) Copper(II) Percholatehydrate
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作者 LIBao-Zong WANGShou-Wu +1 位作者 LIBao-Long ZHANGYong 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第7期727-730,共4页
The copper(II) complex [Cu(teta)N(CN)2](ClO4)H2O (teta = 5,7,7,12,14,14- hexamethyl-1,4,8,11-tetraazacyclotetradecane) has been synthesized and the crystal structure was determined by single-crystal X-ray diffraction.... The copper(II) complex [Cu(teta)N(CN)2](ClO4)H2O (teta = 5,7,7,12,14,14- hexamethyl-1,4,8,11-tetraazacyclotetradecane) has been synthesized and the crystal structure was determined by single-crystal X-ray diffraction. Crystal data: C18H38ClCuN7O5, monoclinic, space group P21/n, a = 8.796(3), b = 11.885(4), c = 23.054(9) , b = 97.540(4)o, V = 2389.3(15) 3, Mr = 531.54, Z = 4, Dc = 1.478 g/cm3, F(000) = 1124, ?= 1.070 mm-1, the final R = 0.0566 and wR = 0.1162 for 4749 observed reflections (I > 2s(I)). The center copper ion is coordinated by five nitrogen atoms in a square pyramidal geometry, with four from the macrocyclic ligand teta and the other one from a nitrile nitrogen atom of dicyanamide which is coordinated to the metal atoms as uni-dentate manner via nitrile nitrogen atom. 展开更多
关键词 MACROCYCLIC copper complex DICYANAMIDE SYNTHESIS crystal structure
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Synthesis and Crystal Structure of Pd(AETYF)Cl_2CH_2Cl_2 [AETYF = 4'5'Diaza-9' (4,5-bis(ethylthio)-1,3-dithiole-2-ylidene)-fluorene]
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作者 ZHUQin-Yu DAIJie +3 位作者 ZHANGYong JIADing-Xian ZHANGJia-Sheng GUOLing 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2004年第6期551-554,共4页
A stable Pd(II) compound Pd(AETYF)Cl2CH2Cl2 (AETYF = 4?5?diaza-9? (4,5-bis(ethylthio)-1,3-dithiole-2-ylidene)-fluorene) has been synthesized and its crystal structure was determined by X-ray crystallography. The cryst... A stable Pd(II) compound Pd(AETYF)Cl2CH2Cl2 (AETYF = 4?5?diaza-9? (4,5-bis(ethylthio)-1,3-dithiole-2-ylidene)-fluorene) has been synthesized and its crystal structure was determined by X-ray crystallography. The crystal is of monoclinic, space group P21/c with a = 15.249(6), b = 8.619(3), c = 19.078(7) ? b = 106.932(8), C19H18Cl4N2PdS4, Mr = 650.79, V = 2398.6(16) 3, Z = 4, Dc = 1.802 g/cm3, F(000) = 1296, m = 1.579 mm-1, Npar = 268, the final R = 0.0538 and wR = 0.1282 for 5068 observed reflections with I > 2s(I). The crystal structure determi- nation shows that the atoms of the molecule, except two ethyl-groups, are conjugated in a quasi- plane and these molecules are further stacked or contacted via plane to plane or edge to edge p-p interactions, forming parallel molecular chains along the b axis. 展开更多
关键词 diaza-fluorene palladium complex crystal structure intermolecular interaction
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Construction and Analysis of N-phosphoryl Peptide Libraries
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作者 ShuXiaCAO JianChenZHANG +3 位作者 MingYuNIU KuiLU XinChengLIAO YuFenZHAO 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第6期652-654,共3页
N-Phosphoryl peptide libraries were constructed by transformation from homo-oligopeptide libraries, which was synthesized by self-assembly of amino acids with the assistance of phosphorus oxychloride. Electrospray ion... N-Phosphoryl peptide libraries were constructed by transformation from homo-oligopeptide libraries, which was synthesized by self-assembly of amino acids with the assistance of phosphorus oxychloride. Electrospray ionization mass spectrometry (ESI-MS) was used to monitor the reaction. 展开更多
关键词 N-Phosphoryl peptide library homo-oligopeptide library electrospray ionization mass spectrometry (ESI-MS).
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Synthesis and Crystal Structure of Bis(nitrate)bis(N-n-octyl-α-pyrrolidone)uranyl (II)
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作者 朱利明 郁开北 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2002年第5期501-504,共4页
The crystal structure of the title compound UO2(NO3)2[CH2(CH2)2CONC8H17] was determined by single-crystal X-ray diffraction. Crystal data: triclinic, space group P , a = 7.456(2), b = 8.371(2), c = 13.470(3) ? ?= 95.6... The crystal structure of the title compound UO2(NO3)2[CH2(CH2)2CONC8H17] was determined by single-crystal X-ray diffraction. Crystal data: triclinic, space group P , a = 7.456(2), b = 8.371(2), c = 13.470(3) ? ?= 95.66(1), ?= 94.64(2), ?= 102.67(2), C24H46N4O10U, Mr = 788.68, V = 811.7(3) ?, Dc = 1.613 g/cm3, Z = 1, F(000) = 390, ?= 5.052 mm-1, the final R = 0.0256 and wR = 0.0568 for 2826 observed reflections (I > 2(I)). The central uranyl ions are coordinated by six oxygen atoms. Two of them are from the carbonyl groups of N-octyl-a-pyrrolidone molecules, and the other four from two nitrate groups. 展开更多
关键词 N-n-octyl-a-pyrrolidone uranyl complex crystal structure
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