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Hyaluronic acid injection in the auricular base for the aesthetic correction of lying ears:A retrospective study 被引量:1
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作者 Zhezhen Xiong Zhengzheng Jiang +3 位作者 Yaping Bai Minxue Liang Weitai Jiang Kai Liu 《Chinese Journal of Plastic and Reconstructive Surgery》 2023年第1期8-12,共5页
Background Ears play an important role in facial profiles.Lying ears are not perceived favorably in Asian cultures;therefore,surgical procedures are implemented to adjust this defect.However,surgery has complications ... Background Ears play an important role in facial profiles.Lying ears are not perceived favorably in Asian cultures;therefore,surgical procedures are implemented to adjust this defect.However,surgery has complications and requires recovery time.We introduced a hyaluronic acid(HA)injection technique to aesthetically improve ear prominence.Methods This retrospective study examined 25 Chinese patients aged 20-47 years with congenital lying ears who received HA injections in the auricular base at Shanghai Ninth People’s Hospital and Hangzhou Yijie Medical Cosmetology Clinic between November 2019 and December 2022.The average injection volume was 6.32±1.22 mL in the auricular base unilaterally,and the follow-up time ranged from 6 to 24 months.Morphological measurement data were recorded.Two-dimensional(2D)and three-dimensional(3D)images were obtained to evaluate the effects.Results All patients showed improvements in ear prominence.The cranioauricular angle(CAA)increased from 22.24°±4.53°to 65.90°±5.38°immediately post-injection and was maintained at 49.18°±4.74°6 months later.The ear projection(EP)increased from 14.75±2.72 mm to 26.26±2.94 mm immediately post-injection and was 22.51±2.68 mm after 6 months.No serious complications were noted.Conclusion HA injection in the auricular base effectively corrected the lying ears and aesthetically optimized the facial profile.It also had a face-lift effect that made the face look younger and more compact.The injection procedure was minimally invasive and required no recovery period.The effect was maintained for a long time and was satisfactory. 展开更多
关键词 Hyaluronic acid Lying ears Auricular base Facial rejuvenation
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Acetalization of carbonyl compounds with 2,2,4-trimethyl-1,3-pentanedio catalyzed by novel carbon based solid acid catalyst 被引量:3
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作者 Ling Liu Yuechang Zhao Shan Gan Xuezheng Liang Jianguo Yang Mingyuan He 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2008年第2期149-152,共4页
The synthesis of 2, 4-diisopropyl-5,5-dimethy1- 1.3-dioxane through the acetalization of isobutyraldehyde with 2, 2, 4-trimethy1-1,3-pentanediol (TMPD) catalyzed by the novel carbon based acid was first carried out.... The synthesis of 2, 4-diisopropyl-5,5-dimethy1- 1.3-dioxane through the acetalization of isobutyraldehyde with 2, 2, 4-trimethy1-1,3-pentanediol (TMPD) catalyzed by the novel carbon based acid was first carried out. High conversion (≥98%) and specific selectivity were obtained using the novel carbon based acid, which kept high activity after it was reused 5 times. Moreover. the catalyst could be used to catalyze the acetalization and ketalization of different aldehydes and ketones with superior yield. The yield of several products was over 90%. The novel heterogeneous catalyst has the distinct advantages of high activity, strikingly simple workup procedure, non-pollution, and reusability, which will contribute to the success of the green process greatly. 展开更多
关键词 TMPD ACETALIZATION carbon based solid strong acid isobutylaldehyde
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Coordination and Photoisomerization of Azobenzene-Amino Acid Schiff Base Copper(II) Complexes to Lysozyme
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作者 Yuto Kuroda Ryotaro Miyazaki +2 位作者 Daiki Shimonishi Daisuke Nakane Takashiro Akitsu 《Journal of Materials Science and Chemical Engineering》 CAS 2023年第3期34-44,共11页
In this study, we exhibited an amino acid (arginine and threonine) derivative Schiff base copper(II) complexes incorporating an azobenzene moiety as a photoresponsive site and conjugated it to egg white lysozyme, a we... In this study, we exhibited an amino acid (arginine and threonine) derivative Schiff base copper(II) complexes incorporating an azobenzene moiety as a photoresponsive site and conjugated it to egg white lysozyme, a well-known protein, to change ligand conformation under binding to lysozyme. Among several spectroscopic investigations, ESR clearly showed that the nitrogen atom of the amino acid residue of lysozyme was bound to the paramagnetic copper(II) ion of the complex, and UV light irradiation confirmed photoisomerization of the azobenzene moiety of the ligand to cis-form. The binding mode was considered by means of spectroscopic as well as computational methods, whereas complete crystallographic verification was still a preliminary stage. 展开更多
关键词 AZOBENZENE Schiff base Copper Amino acid LYSOZYME Artificial Metalloprotein
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Preparation and Properties of Vegetable-Oil-Based Thioether Polyol and Ethyl Cellulose Supramolecular Composite Films
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作者 Ruyu Yan Jian Fang +7 位作者 Xiaohua Yang Na Yao Mei Li Yuan Nie Tianxiang Deng Haiyang Ding Lina Xu Shouhai Li 《Journal of Renewable Materials》 SCIE EI 2023年第4期1937-1950,共14页
Ethyl cellulose(EC),an important biomass-based material,has excellent film-forming properties.Nevertheless,the high interchain hydrogen bond interaction leads to a high glass transition temperature of EC,which makes i... Ethyl cellulose(EC),an important biomass-based material,has excellent film-forming properties.Nevertheless,the high interchain hydrogen bond interaction leads to a high glass transition temperature of EC,which makes it too brittle to be used widely.The hydroxyl group on EC can form a supramolecular system in the form of a non-covalent bond with an effective plasticizer.In this study,an important vegetable-oil-based derivative named dimer fatty acid was used to prepare a novel special plasticizer for EC.Dimer-fatty-acid-based thioether polyol(DATP)was synthesized and used to modify ethyl cellulose films.The supramolecular composite films of DATP and ethyl cellulose were designed using the newly-formed van der Waals force.The thermal stability,morphology,hydrophilicity,and mechanical properties of the composite films were all tested.Pure EC is fragile,and the addition of DATP makes the ethyl cellulose films more flexible.The elongation at the break of EC supramolecular films increased and the tensile strength decreased with the increasing DATP content.The elongation at the break of EC/DATP(60/40)and EC/DATP(50/50)was up to 40.3%and 43.4%,respectively.Noticeably,the thermal initial degradation temperature of the film with 10%DATP is higher than that of pure EC,which may be attributed to the formation of a better supramolecular system in this composite film.The application of bio-based material(EC)is environmentally friendly,and the novel DATP can be used as a special and effective plasticizer to prepare flexible EC films,making it more widely used in energy,chemical industry,materials,agriculture,medicine,and other fields. 展开更多
关键词 Ethyl cellulose dimeric fatty acid based thioether polyol supramolecular system composite films
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Characterization of Amino Acid Based Molecular Micelles with Molecular Modeling 被引量:2
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作者 Alexander Billiot Yayin Fang Kevin F. Morris 《Open Journal of Physical Chemistry》 2019年第4期221-240,共20页
The enantiomers of chiral drugs often have different potencies, toxicities, and biochemical properties. Therefore, the FDA and other worldwide regulatory agencies require manufactures to test and prove the enantiomeri... The enantiomers of chiral drugs often have different potencies, toxicities, and biochemical properties. Therefore, the FDA and other worldwide regulatory agencies require manufactures to test and prove the enantiomeric purity of chiral drugs. Amino acid based molecular micelles (AABMM) have been used in chiral CE separations since the 1990’s because of their low environmental impact and because their properties can easily be tuned by changing the amino acids in the chiral surfactant head groups. Using molecular dynamics simulations to investigate the structures and properties of AABMM is part of an ongoing study focusing on investigating and elucidating the factors responsible for chiral recognition with AABMM. The results will be useful for the proper design and selection of more efficient chiral selectors. The micelles investigated contained approximately twenty covalently linked surfactant monomers. Each monomer was in turn composed of an undecyl hydrocarbon chain bound to a dipeptide headgroup containing of all combinations of L-Alanine, L-Valine, and L-Leucine. These materials are of interest because they are effective chiral selectors in capillary electrophoresis separations. Molecular dynamics simulation analyses were used to investigate how the sizes and positions of the headgroup amino acid R-groups affected the solvent accessible surface areas of each AABMM chiral center. In addition, headgroup dihedral angle analyses were used to investigate how amino acid R-group size and position affected the overall headgroup conformations. Finally, distance measurements were used to study the structural and conformational flexibilities of each AABMM headgroup. All analyses were performed in the context of a broader study focused on developing structure-based predictive tools to identify the factors responsible for a) self-assembly, b) function, c) higher ordered structure and d) molecular recognition of these amino acid based molecular micelles. 展开更多
关键词 AMINO acid based MOLECULAR Micelles MOLECULAR Modeling COMPUTATIONAL CHEMISTRY
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Effects of an AMPS-Modified Polyacrylic Acid Superplasticizer on the Performance of Cement-based Materials 被引量:3
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作者 陈宝璠 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2015年第1期109-116,共8页
A self-made AMPS-modified polyacrylic acid superplasticizer and two others of the same type but with different molecular structures, which are commercially available, are used in this study to investigate the effect o... A self-made AMPS-modified polyacrylic acid superplasticizer and two others of the same type but with different molecular structures, which are commercially available, are used in this study to investigate the effect of a 2-acrylamide-2-methyl propylene sulfonic (AMPS)-modified polyacrylic acid superplasticizer on the properties of cement-based materials. In the experiments, initial fluidity, 1 and 2 h fluidity over time after admixtion, bleeding rate of the net cement mortar, and adsorption capacity and rate of cement particles are determined by adding different dosages of the three superplasticizers into the cement paste to characterize the dispersivity and the dispersion retention capability of each superplasticizer. Water-reducing rates of three kinds of mortars are simultaneously determined to characterize the water-reducing capacity of each superplasticizer, as well as the 3 and 28 d compressive strengths to characterize the compression resistance. Results show that water-reducing effect and fluidity better maintain the capability of the AMPS-modified polyacrylic acid superplasticizer than the two commercially available polyacrylic acid superplasticizers, and the compressive strengths after 3 and 28 d show significant growth. In conclusion, the effects of water reduction and strengthening of the AMPS-modified polyacrylic acid superplasticizer are evidently better than those of the two commercially available polyacrylic acid superplasticizers. 展开更多
关键词 AMPS-modified polyacrylic acid superplasticizer cement-based materials polyacrylic acid superplasticizer PERFORMANCE
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Wet carbon-based solid acid/NaNO_3 as a mild and efficient reagent for nitration of aromatic compound under solvent free conditions 被引量:5
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作者 Arash Shokrolahi Abbas Zali Mohammad Hossein Keshavarz 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第9期1064-1066,共3页
Nitro aromatic compound can be obtained in high yields via nitration of aromatic compound with wet carbon-based solid acid and NaNO_3 under solvent free oxidation at room temperature.
关键词 Carbon-based solid acid Sodium nitrate NITRATION Solvent free conditions
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Two Dehydroabietic Acid-based Arylamines: Synthesis, Crystal Structure and Fluorescent Properties 被引量:2
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作者 高宏 宋杰 +1 位作者 商士斌 宋湛谦 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2013年第3期396-402,共7页
Two dehydroabietic acid-based arylamines have been synthesized and characterized by FTIR, 1H NMR, 13C NMR, MS spectra and elemental analysis. Their spatial structures were determined by X-ray diffraction analysis. UV-... Two dehydroabietic acid-based arylamines have been synthesized and characterized by FTIR, 1H NMR, 13C NMR, MS spectra and elemental analysis. Their spatial structures were determined by X-ray diffraction analysis. UV-Vis absorption and fluorescence spectral characteristics of these compounds in methanol were investigated. Their fluorescence emission spectra in different polarity solvents were further evaluated. Fluorescent properties and structural relationship of the compounds showed that fluorescence intensity and quantum yield inversely increase with the non-coplanar degree. In addition, the solvent polarity has different effects on the fluorescence emission spectra of two compounds. 展开更多
关键词 dehydroabietic acid-based arylamine SYNTHESIS crystal structure fluorescent property
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Wet carbon-based solid acid/potassium permanganate as an efficient heterogeneous reagents for oxidation of alcohols under mild conditions 被引量:1
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作者 Arash Shokrolahi Abbas Zali Mohammad Hossein Keshavarz 《Chinese Chemical Letters》 SCIE CAS CSCD 2008年第11期1274-1276,共3页
Wet carbon-based solid acid and potassium permanganate were used as new reagents for oxidation of alcohols to their corresponding aldehydes and ketones in heterogeneous mixtures. The experiments were done moderately a... Wet carbon-based solid acid and potassium permanganate were used as new reagents for oxidation of alcohols to their corresponding aldehydes and ketones in heterogeneous mixtures. The experiments were done moderately at mild condition and high yields in suitable times were obtained. 展开更多
关键词 Carbon-based solid acid Potassium permanganate OXIDATION ALCOHOLS
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Determination of pKa values of alendronate sodium in aqueous solution by piecewise linear regression based on acid-base potentiometric titration 被引量:2
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作者 Jing Ke Hanfei Dou +3 位作者 Ximin Zhang Dushimabararezi Serge Uhagaze Xiali Ding Yuming Dong 《Journal of Pharmaceutical Analysis》 SCIE CAS 2016年第6期404-409,共6页
As a mono-sodium salt form of alendronic acid,alendronate sodium presents multi-level ionization for the dissociation of its four hydroxyl groups.The dissociation constants of alendronate sodium were determined in thi... As a mono-sodium salt form of alendronic acid,alendronate sodium presents multi-level ionization for the dissociation of its four hydroxyl groups.The dissociation constants of alendronate sodium were determined in this work by studying the piecewise linear relationship between volume of titrant and p H value based on acidbase potentiometric titration reaction.The distribution curves of alendronate sodium were drawn according to the determined p Ka values.There were 4 dissociation constants(pKa_1=2.43,pKa_2=7.55,pKa_3=10.80,pKa_4=11.99,respectively) of alendronate sodium,and 12 existing forms,of which 4 could be ignored,existing in different p H environments. 展开更多
关键词 Dissociation CONSTANTS ALENDRONATE SODIUM Distribution curve Piecewise linear regression acid-base POTENTIOMETRIC TITRATION
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Development of Nucleic Acid Sequence-Based Amplification Assay for Detection of Macrobrachium rosenbergii Nodavirus 被引量:2
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作者 Feng LIN Li LIU +5 位作者 Dong QIAN Guijie HAO Pengcheng SHENG Zheng CAO Xuemei YUAN Jinyu SHEN 《Agricultural Biotechnology》 CAS 2014年第3期42-45,共4页
A nucleic acid sequence-based amplification(NASBA)assay was established for the detection of Macrobrachium rosenbergii Nodavirus(MrNV).The specific primers were designed according to the high conserved region of R... A nucleic acid sequence-based amplification(NASBA)assay was established for the detection of Macrobrachium rosenbergii Nodavirus(MrNV).The specific primers were designed according to the high conserved region of RNA2 sequence of MrNV.The 224 bp specific amplification product was obtained in positive sample determined with 3%agarose gel electrophoresis,while no product was generated from shrimp infected with other viruses including DNA viruses(IHHNV,WSSV)and RNA viruses(TSV,IMNV,YHV).The detecting limit of the assay was 8pg nucleic acid,which is more sensitive than that of PCR method. 展开更多
关键词 Macrobrachium rosenbergii Nodavirus Nucleic acid sequence-based amplification DETECTION
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Non-covalent Bonded 3D Supramolecular Architectures Based on Acid-base Adducts 被引量:3
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作者 李卫东 方旭 +1 位作者 乔瑞 陈水生 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2016年第1期46-54,共9页
Two novel acid-base adducts,[H2L1^2+](Hpbda)2(1,L1 = 1,4-di(lH-imidazol-4-yl)benzene,H2pbda = 1,4-benzenedicarboxylic acid) and[H2L2^2+](NO3)2(2,L2 = l,4-di(l-carboxymethyl-imidazol-4-yl)benzene),have be... Two novel acid-base adducts,[H2L1^2+](Hpbda)2(1,L1 = 1,4-di(lH-imidazol-4-yl)benzene,H2pbda = 1,4-benzenedicarboxylic acid) and[H2L2^2+](NO3)2(2,L2 = l,4-di(l-carboxymethyl-imidazol-4-yl)benzene),have been prepared and characterized by single-crystal X-ray diffraction,IR spectroscopy and elemental analysis.Compound 1 crystallizes in monoclinic,space group P21/n with a = 5.3525(11),b = 9.1471(19),c = 19.314(4) ?,β = 92.342(3)°,V= 944.8(3) A°3,Z = 2,C16H16N6O(10),Mr = 452.35,Dc = 1.590 g/cm^3,μ = 0.135 mm^-1,S = 1.058,F(000) = 468,the final R = 0.0661 and wR = 0.1887 for 2298 observed reflections(I〉 2σ(I)).Compound 2 crystallizes in monoclinic,space group P21/c with a = 9.6923(10),b = 17.2950(17),c = 7.1880(7) ?,β =94.801(2)°,V= 1200.7(2)A°3,Z = 2,C(28)H(22)N4O8,Mr = 542.50,Dc = 1.501 g/cm^3,μ = 0.112 mm^-1,S= 1.060,F(000) = 564,the final R = 0.0394 and wR = 0.1017 for 2768 observed reflections(I 〉2σ(I)).In the title compounds,both of L1 and L2 ligands act as weak base to accept protons to exhibit diprotonated H2L1^2+ and H2L2^2+ form,which can effectively employ as hydrogen bonding donors to combine anion moieties to form binary adducts respectively.In the crystal packing diagram of two polymers,there exist extensive noncovalent interactions including charge-transfer interactions,C(N)-H…π and N-H…O,C-H…O,O-H…O hydrogen bonding interactions between co-crystal moieties which consolidate the structures of supramolecular polymers,thus generating three-dimensional(3D) frameworks. 展开更多
关键词 synthesis acid-base adducts crystal structure noncovalent interactions
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Binol Based Chirality Conversion Reagents for Underivatized Amino Acids
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作者 Krishnaswamy Velmurugan Lijun Tang Raju Nandhakumar 《International Journal of Organic Chemistry》 2014年第1期40-47,共8页
Four binol based pyrrole carboxamide chiral receptors has been synthesized and effectively used as a Chirality Conversion Reagent (CCR) for underivatized amino acids. Three points of interactions take place for the co... Four binol based pyrrole carboxamide chiral receptors has been synthesized and effectively used as a Chirality Conversion Reagent (CCR) for underivatized amino acids. Three points of interactions take place for the conversion process. They are the reversible imine formation, the internal resonance assisted Hydrogen Bonding (RAHB) and the additional hydrogen bonds between the amino acids and the heterocylic moiety of the pendant groups. The conversion efficiency of all the receptors was found to be comparable with those of the receptors reported earlier. 展开更多
关键词 BINOL based Receptors CHIRAL Recognition AMINO acids AMINO Alcohols CHIRAL Inversion 1H-NMR
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Prospects for nucleic acid-based therapeutics against hepatitis C virus 被引量:1
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作者 Chang Ho Lee Ji Hyun Kim Seong-Wook Lee 《World Journal of Gastroenterology》 SCIE CAS 2013年第47期8949-8962,共14页
In this review,we discuss recent advances in nucleic acid-based therapeutic technologies that target hepatitis C virus(HCV)infection.Because the HCV genome is present exclusively in RNA form during replication,various... In this review,we discuss recent advances in nucleic acid-based therapeutic technologies that target hepatitis C virus(HCV)infection.Because the HCV genome is present exclusively in RNA form during replication,various nucleic acid-based therapeutic approaches targeting the HCV genome,such as ribozymes,aptamers,siRNAs,and antisense oligonucleotides,have been suggested as potential tools against HCV.Nucleic acids are potentially immunogenic and typically require a delivery tool to be utilized as therapeutics.These limitations have hampered the clinical development of nucleic acid-based therapeutics.However,despite these limitations,nucleic acid-based therapeutics has clinical value due to their great specificity,easy and large-scale synthesis with chemical methods,and pharmaceutical flexibility.Moreover,nucleic acid therapeutics are expected to broaden the range of targetable molecules essential for the HCV replication cycle,and therefore they may prove to be more effective than existing therapeutics,such as interferon-αand ribavirin combination therapy.This review focuses on the current status and future prospects of ribozymes,aptamers,siRNAs,and antisense oligonucleotides as therapeutic reagents against HCV. 展开更多
关键词 Hepatitis C virus Nucleic acid-based THERAPEUTICS RIBOZYME APTAMER siRNA ANTISENSE OLIGONUCLEOTIDE
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Flexible Bis(benzimidazole)-based Ligands Directed the Structure Characteristics of Coordination Polymers Based on Diphenic Acid Co-ligands:Syntheses, Structures and Properties 被引量:1
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作者 TU Chang-Zheng YANG Yu-Ting +2 位作者 XU Li-Li YAN Bang-Ling WANG Fan 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2019年第1期155-164,5,共11页
Two new coordination polymers [Cu_2(bbim)(dpa)_2(C_2H_5OH)_2](1), [Co(dpa)_2(bbbm)](2)(H_2dpa = diphenic acid, bbim = 1,1?-(1,6-hexanediyl)bis-1H-benzimidazole, bbbm = 1,1?-(1,4-butanediyl)bis-1 H-benzimidazole) const... Two new coordination polymers [Cu_2(bbim)(dpa)_2(C_2H_5OH)_2](1), [Co(dpa)_2(bbbm)](2)(H_2dpa = diphenic acid, bbim = 1,1?-(1,6-hexanediyl)bis-1H-benzimidazole, bbbm = 1,1?-(1,4-butanediyl)bis-1 H-benzimidazole) constructed from bis(benzimidazole)-based ligands with different lengths and diphenic acid co-ligand have been synthesized under solvothermal conditions.Complex 1 possesses Cu-dpa helical chains. The adjacent chains are connected by the bbim ligands into two-dimensional(2D) 3-connected(63) topology. Differently, the layer structure of 2 was consisted by one-dimensional chains containing alternated 8-and 18-membered rings. Furthermore,the thermal stability and fluorescence property for all crystalline materials have been investigated. 展开更多
关键词 coordination polymer crystal structure diphenic acid bis(benzimidazole)-based LIGANDS fluorescence
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Chiral Recognition of Dansyl Derivatives with an Amino Acid-Based Molecular Micelle: A Molecular Dynamics Investigation
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作者 Mauro Garcia Nathan Black +3 位作者 Eugene Billiot Fereshteh Billiot Kevin F. Morris Yayin Fang 《Open Journal of Physical Chemistry》 2021年第2期64-86,共23页
In this study, the chiral separation mechanisms of Dansyl amino acids, including Dansyl-Leucine (Dans-Leu), Dansyl-Norleucine (Dans-Nor), Dansyl-Tryptophan (Dans-Trp) and Dansyl-Phenylalanine (Dans-Phe) binding to pol... In this study, the chiral separation mechanisms of Dansyl amino acids, including Dansyl-Leucine (Dans-Leu), Dansyl-Norleucine (Dans-Nor), Dansyl-Tryptophan (Dans-Trp) and Dansyl-Phenylalanine (Dans-Phe) binding to poly-sodium </span><span style="font-family:Verdana;"><i></span><i><span style="font-family:Verdana;">N</span></i><i><span style="font-family:Verdana;"></i></span></i><span style="font-family:Verdana;">-undecanoyl-(L)-Leucylvalinate, poly (SULV), were investigated using molecular dynamics simulations. Micellar electrokinetic chromatography (MEKC) has previously shown that when separating the enantiomers of these aforementioned Dansyl amino acids, the L-enantiomers bind stronger to poly (SULV) than the D-enantiomers. This study aims to investigate the molecular interactions that govern chiral recognition in these systems using computational methods. This study reveals that the computationally-calculated binding free energy values for Dansyl enantiomers binding to poly (SULV) are in agreement with the enantiomeric order produced in experimental MEKC studies. The L-enantiomers of Dans-Leu, Dans-Nor, Dans-Trp, and Dans-Phe binding to their preferred binding pockets in poly (SULV) yielded binding free energy values of </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">21.8938, </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">22.1763, </span><span style="font-family:Verdana;">-</span><span style="font-family:""><span style="font-family:Verdana;">21.3329 </span><span style="font-family:Verdana;">and </span></span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">13.3349 kJ</span><span style="font-family:Verdana;">&middot;</span><span style="font-family:Verdana;">mol</span><sup><span style="font-family:Verdana;">-</span></sup><sup><span style="font-family:Verdana;">1</span></sup><span style="font-family:Verdana;">, respectively. The D-enantiomers of Dans-Leu, Dans-Nor</span><span style="font-family:Verdana;">, Dans-Trp, and Dans-Phe binding to their preferred binding pockets in poly (SULV) yielded binding free energy values of </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">14.5811, </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">15.9457, </span><span style="font-family:Verdana;">-</span><span style="font-family:Verdana;">13.6408, and </span><span style="font-family:Verdana;">-</span><span style="font-family:""><span style="font-family:Verdana;">12.0959</span><b> </b><span style="font-family:Verdana;">kJ</span></span><span style="font-family:Verdana;">&middot;</span><span style="font-family:Verdana;">mol</span><sup><span style="font-family:Verdana;">-</span></sup><sup><span style="font-family:Verdana;">1</span></sup><span style="font-family:Verdana;">, respectively. Furthermore, hydrogen bonding analyses w</span><span style="font-family:Verdana;">ere</span><span style="font-family:Verdana;"> used to investigate and elucidate the molecular interactions that govern chiral recognition in these molecular systems. 展开更多
关键词 Amino acid based Molecular Micelles Molecular Modeling Computational Chemistry Chiral Recognition
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Comparative Study on the Acid-Base Indicator Properties of Natural Dye, Turmeric Rhizome (Curcuma longa) and Synthetic Dyes
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作者 Genevive Chinyere Onuegbu Onyekachi Onyinyechi Nnorom Gerald Okwuchi Onyedika 《Journal of Textile Science and Technology》 2023年第1期20-29,共10页
Acid-Base Indicator, Turmeric Rhizome (Curcuma longa) was extracted from the root of a turmeric plant. The turmeric was peeled, washed and dried in an oven at 60&deg;C. It was ground into powder and soaked in hot ... Acid-Base Indicator, Turmeric Rhizome (Curcuma longa) was extracted from the root of a turmeric plant. The turmeric was peeled, washed and dried in an oven at 60&deg;C. It was ground into powder and soaked in hot and cold ethanol for the extraction. The extract was filtered and part of it was concentrated to yield a reasonable quantity of turmeric indicator. On standardization of acid with a base, 0.05 M base respectively of Sodium hydroxide (NaOH), sodium carbonate (Na<sub>2</sub>CO<sub>3</sub>) and Disodium borate (B<sub>4</sub>Na<sub>2</sub>O<sub>7</sub>) were used. Hot and cold extracts of turmeric were used as indicators and were compared with methyl orange and phenolphthalein. On the preliminary test carried out, hot and cold turmeric indicator showed yellow colour in acid medium and orange colour in the base. Methyl orange showed red colour in acid but yellow in the base, phenolphthalein was colourless in acid but pink in the base. During titration there were colour changes at the end points in the entire test carried out. The average volumes at ends points were calculated, the molar concentrations and mass concentrations of the acids used were also determined. The results showed that there was no difference between the natural indicators used and the existing synthetic indicators which are toxic to our environment. 展开更多
关键词 Turmeric Rhizome EXTRACTION acid-base Indicator Methyl Orange PHENOLPHTHALEIN
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Studies on Zeolite Modified Electrode(Ⅰ)─Ascorbic Acid Sensor Based on Carbon Paste Electrode Containing Fe(Ⅲ)Y Zeolite
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作者 Ming Zhu ZOU Hong Ding XU +1 位作者 Jie LU Qin Hua Ru (a Department of Chemistry, Jilin University, Changchun 130023 b Department of Chemistry, the North-East Normal University, Changchun 130022) (To whom correspondence should be addressed ) 《Chinese Chemical Letters》 SCIE CAS CSCD 1997年第3期247-250,共4页
A new ascorbic acid sensor constituted of carbon paste and Fe(Ⅲ)Y zeolite was studied.The characters of the sensor such as linear range. potential window、apparen Michaelis constant、response time、stability and accu... A new ascorbic acid sensor constituted of carbon paste and Fe(Ⅲ)Y zeolite was studied.The characters of the sensor such as linear range. potential window、apparen Michaelis constant、response time、stability and accuracy wee investigated. The experimental results indicate that the analytical performance of the sensor is satisfactory. 展开更多
关键词 Ascorbic acid Sensor based on Carbon Paste Electrode Containing Fe Y Zeolite Studies on Zeolite Modified Electrode
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Effects of Yttrium Doping on the Performance of Ru-Based Catalysts for Hydrogenation of Fatty Acid Methyl Ester 被引量:1
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作者 Qi Lin Huirong Zheng +2 位作者 Guocai Zheng Xinzhong Li Benyong Lou 《International Journal of Organic Chemistry》 2014年第4期219-224,共6页
The highly dispersed supported ruthenium-yttrium (Ru-Y) bimetallic catalysts were prepared by impregnation method and their catalytic performance for hydrogenation of ester was fully investigated. The catalyst was cha... The highly dispersed supported ruthenium-yttrium (Ru-Y) bimetallic catalysts were prepared by impregnation method and their catalytic performance for hydrogenation of ester was fully investigated. The catalyst was characterized by X-ray diffraction and field emission scanning electron microscopy. The results show that the average particle diameter of the bimetallic crystallites was less than 10 nm. The effects of the reaction temperature, the hydrogen pressure, the amount of catalyst and the proportion of yttrium in catalyst on the hydrogenation of ester were studied. The experimental results show that the introduction of yttrium not only changed the chemical and textural properties of ruthenium-based catalyst but also controlled the formation of Ru-Y alloy. The Ru-Y catalyst (Ru-2%Y/TiO2) exhibited high catalytic activity and good selectivity towards the higher alcohols. Under optimal reaction conditions of 240°C and 5 MPa hydrogen pressure, the conversion of palm oil esters was above 93.4% while the selectivity towards alcohol was above 99.0%. 展开更多
关键词 Yttrium-Doped Ruthenium-based Catalyst FATTY acid Methyl Ester HYDROGENATION
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Preparation, Characterization and Catalytic Activity of Alkyl Benzene Sulfonic Acid Carbon-Based Acid Catalyst
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作者 Huoxin Luan Yunqiang Wu +5 位作者 Wenxiang Wu Quansheng Chen Hailing Zhang Kang Liu Guangmiao Qu Wei Ding 《Journal of Surface Engineered Materials and Advanced Technology》 2015年第2期93-101,共9页
Based on starch and series of alkyl benzene sulfonic acid as the materials, a novel carbon-based solid acid catalyst is synthesized using hydrothermal method. This catalyst exhibits much higher catalytic activity in t... Based on starch and series of alkyl benzene sulfonic acid as the materials, a novel carbon-based solid acid catalyst is synthesized using hydrothermal method. This catalyst exhibits much higher catalytic activity in the reaction of esterification of Mono-fatty alcohol polyoxyethylene maleate esters with 1,4-butanediol. The structure of carbon-based solid acid catalyst was charactered by IR and XRD, characterizations showed that this catalyst exhibited high –SO3H loading. Reusability of the carbon-based solid acid catalyst for esterification showed that after recycling five times the activity remained unchanged. 展开更多
关键词 ALKYL Benzene Sulfonic acid Carbon-based Solid acid Catalyst ESTERIFICATION
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