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Synthesis,structures,thermal and magnetic properties of a series of lanthanide Ln=Sm,Gd,Er,Yb complexes with 4-quinolineacarboxylate 被引量:2
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作者 高倩 谢亚勃 +1 位作者 张翀 孙继红 《Journal of Rare Earths》 SCIE EI CAS CSCD 2009年第1期12-17,共6页
A series of lanthanide binuclear complexes, Ln2(L)6(H2O)4·2H2O(Ln=Sm(Ⅲ), Gd(Ⅲ), Er(Ⅲ), Yb(Ⅲ), HL=4-quinolinea-carboxylic acid, were synthesized by reactions of corresponding rare earth salts with... A series of lanthanide binuclear complexes, Ln2(L)6(H2O)4·2H2O(Ln=Sm(Ⅲ), Gd(Ⅲ), Er(Ⅲ), Yb(Ⅲ), HL=4-quinolinea-carboxylic acid, were synthesized by reactions of corresponding rare earth salts with 4-quinolineacarboxylic acid at room temperature and were characterized by elemental analysis, IR spectroscopy, and single-crystal X-ray diffraction.X-ray diffraction analyses showed that they exhibited the same binuclear architecture and crystallized in monoclinic system and P21/c space group.In four complexes, each metal center adopted nine-coordinated mode coordinated by nine O atoms from two H2O molecules and three carboxyls of three ligands, and HL showed three different coordination modes.The variable-temperature magnetic susceptibility showed that complex Gd2(L)6(H2O)4·2H2O performed very weak antiferromagnetic property at low temperature and exchange was almost paramagnetic at high temperature.Complexes Er2(L)6(H2O)4·2H2O and Yb2(L)6(H2O)4·2H2O performed dominating antiferromagnetic coupling. 展开更多
关键词 4-quinolineacarboxylate lanthanide complex structure magnetic property rare earths
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The Application of Cellulose Nanocrystals Modified with Succinic Anhydride under the Microwave Irradiation for Preparation of Polylactic Acid Nanocomposites
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作者 Ewa Szefer Agnieszka Leszczyńska +1 位作者 Edyta Hebda Krzysztof Pielichowski 《Journal of Renewable Materials》 SCIE EI 2021年第6期1127-1142,共16页
The aim of this work was to use cellulose nanocrystals that were obtained by hydrolysis in phosphoric acid solution and further modified with succinic anhydride in the microwave field for PLA reinforcement.A series of... The aim of this work was to use cellulose nanocrystals that were obtained by hydrolysis in phosphoric acid solution and further modified with succinic anhydride in the microwave field for PLA reinforcement.A series of allbionanocomposites containing unmodified and surface modified cellulose nanocrystals with CNC content in the range of 1–3%_(w.t.) were obtained by melt blending and tested by XRD,SEM,DSC and DMA to investigate the effect of surface esterification of CNCs on the structure,morphology,dynamic mechanical properties of bionanocomposites,as well as phase transitions of PLA in the presence of cellulosic nanofiller.DMA investigations showed the highest increase of storage modulus by ca.7%(335 MPa at 25℃)in the glassy state of PLA for 2%_(w.t.)of unmodified CNC.Though,addition of 2%_(w.t.)of succinylated CNCs caused the highest increase of the onset of glass transition temperature(by 6.2℃)thus widening the temperature range of biocomposite application.The increase of glass transition temperature indicates the strongest interfacial interactions due to improved miscibility of surface modified nanocrystals and thus good dispersion of additive in PLA matrix providing high interface. 展开更多
关键词 Cellulose nanocrystals CNC WHISKERS surface modification succinic anhydride PLA polylactic acid NANOCOMPOSITES
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Staining Effect of Pomegranate Flower Extract on Human Blood Cells: First Results
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作者 Nilgun Guler Kusculuo Huseyin Benli 《Journal of Environmental Science and Engineering(A)》 2017年第5期249-251,共3页
Pomegranate flower plant, popularly known using for the treatment of various diseases, was not investigated as a source of dye for cytological studies using human blood cells. The importance of this study is to appear... Pomegranate flower plant, popularly known using for the treatment of various diseases, was not investigated as a source of dye for cytological studies using human blood cells. The importance of this study is to appear dyeing result of pomegranate flower extract on human blood cells. The natural dye source was pomegranate flower known as roselle and potassium aluminum sulfate (alum = KAISO4' 12H20) was used as mordant or metal salt. Distilled water was used as solvent. Fresh, clean and air-dried flowers were extracted with distilled water at 100℃ for 30 minutes and then filtered. One drop blood from a healthy 20-year woman was spread as a peripheral on to ten plates and dried at nearly 25℃. These slides were stained by soaking in pomegranate flower extract with/without alum (KA1SO4·12H2O) at 100℃ for 60 minutes. Slides were washed with distilled water, dried and done microscobic examination. The different blood cells dyed dark orange in alum mordant media at 100 ℃. As a result, pomegranate flower has the capacity to use dyeing human blood cells such as eosinophil, basophil and neutrophil. 展开更多
关键词 BLOOD NEUTROPHIL pomegranate flower BASOPHIL eosinophil.
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Fabrication and Significant Photoelectrochemical Activity of Titania Nanotubes Modified with Thin Indium Tin Oxide Film
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作者 Katarzyna Siuzdak Mariusz Szkoda +3 位作者 Jakub Karczewski Jacek Ryl Kazimierz Darowicki Katarzyna Grochowska 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2017年第12期1210-1220,共11页
Ordered titanium dioxide nanotubes (TiOaNTs) modified with indium tin oxide (ITO) films were obtained via magnetron sputtering, in which ITO plate was used as a target, onto the as-anodized titania support followe... Ordered titanium dioxide nanotubes (TiOaNTs) modified with indium tin oxide (ITO) films were obtained via magnetron sputtering, in which ITO plate was used as a target, onto the as-anodized titania support followed by the calcination process. The morphology of fabricated material with deposited oxide was investigated using scanning electron microscopy. Raman and UV-Vis spectroscopies were utilized to characterize crystalline phase and optical properties of prepared samples, whereas X-ray photoelectron spectroscopy allowed determining the binding energy of present elements. In the case of titanium, three various oxidation states were identified and also the presence of indium and tin was confirmed. The electrochemical test carried out when the sample was exposed to light allows for selection of the most photoactive material. The highest photocurrent was registered when only 5-nm ITO layer was sputtered, and it equals 256 and 133 μA cm^-2 for the electrode material immersed in 0.5 M KOH and K2SO4 electrolytes, respectively, that is accordingly 3.5 and 4.4 times higher than the one observed for pristine titania. Furthermore, ITO-modified titania exhibits excellent photostability upon prolonged illumination that is of key importance for possible application in light-driven processes. 展开更多
关键词 Titania nanotubes Indium tin oxide PHOTOACTIVITY Anodization Magnetron sputtering Electrochemical activity
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Succinite, Baltic Amber:A Chemical Masterpiece of Nature
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作者 Ewa Wagner-Wysiecka 《宝石和宝石学杂志(中英文)》 CAS 2023年第4期69-87,共19页
Succinite,Baltic amber,is one of the most appreciated fossil resins.Its beauty has fascinated people since prehistoric times.It is a substance,and also gemstone,whose uniqueness is due to its compelling,though still n... Succinite,Baltic amber,is one of the most appreciated fossil resins.Its beauty has fascinated people since prehistoric times.It is a substance,and also gemstone,whose uniqueness is due to its compelling,though still not fully understood,physicochemical nature.In this article,some facts about the physical and chemical properties of succinite in order to find an answer for questions about the unique properties of this resin,such as color,transparency,texture etc.,are discussed.These properties are among the factors that determine the choice of Baltic amber as a gemstone.Commonly known properties of succinite,but also some less obvious features,have been linked to the organic and inorganic chemical composition and structural factors,including the sophisticated supramolecular structure masterfully created by nature.Changes of the properties of succinite used as a jewelry stone are discussed as a reflection of changes in its physicochemical nature.In this light,some methods that can be used to identify succinite(i.e.,infrared spectroscopy and nuclear magnetic resonance spectroscopy)and their relevance to the classification of fossil resins are briefly discussed.This article highlights an important point:only by understanding the chemical and physical nature of the material we able to identify,modify and effectively use the goods that have been given to us by mother nature. 展开更多
关键词 Baltic amber succinite chemical composition PROPERTY
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Unexpected and frustrating transformations of double-decker silsesquioxanes
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作者 Monika Rzonsowska Katarzyna Mituła +6 位作者 Julia Duszczak Małgorzata Kasperkowiak Rafat Januszewski Anita Grześkiewicz Maciej Kubicki Daria Głowacka Beata Dudziec 《Inorganic Chemistry Frontiers》 2022年第2期379-390,共12页
Herein,we disclose an unexpected Si–O–Si cage reorganization that was observed during the standard hydrolytic condensation procedure of tetrasilanol double-decker silsesquioxane(DDSQ)with respective mono-and di-chlo... Herein,we disclose an unexpected Si–O–Si cage reorganization that was observed during the standard hydrolytic condensation procedure of tetrasilanol double-decker silsesquioxane(DDSQ)with respective mono-and di-chlorosilanes.The investigation of this process allowed us to propose the possible mechanism of this transformation.The formation of all structures was confirmed by NMR,FT-IR,and X-ray(for eleven examples)techniques and their thermal stability was verified(TGA).Additionally,we revealed unusual intramolecular homocoupling product formation during the silylative coupling reaction of vinyl-DDSQ derivatives.It deserves to be emphasized that these findings are the first example of a thorough investigation of hydrolytic condensation and the silylative coupling procedures in the chemistry of DDSQs. 展开更多
关键词 standard hydrolytic condensation procedure double decker silsesquioxanes hydrolytic condensation silylative coupling si o si cage reorganization thermal stability cage reorganization NMR
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Exploring the antimicrobial and antioxidant properties of TdGASA2 protein:From molecular insights to a promising natural preservative for Tunisian cheese shelf-life enhancement
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作者 Mohamed Taieb Bouteraa Boutheina Ben Akacha +8 位作者 Miroslava Kacaniova Natalia Cmikova Walid Ben Romdhane Narjes Baazaoui Najeh Soltani Yosra Chouaibi Anis Ben Hsouna Stefania Garzoli Rania Ben Saad 《Food Bioscience》 2024年第5期4252-4262,共11页
Gibberellic acid-stimulated Arabidopsis(GASA)proteins,also known as Snakin proteins,have emerged as key players in plant development and stress tolerance.The investigation of the role of TdGASA2 in host defense respon... Gibberellic acid-stimulated Arabidopsis(GASA)proteins,also known as Snakin proteins,have emerged as key players in plant development and stress tolerance.The investigation of the role of TdGASA2 in host defense responses revealed dynamic expression patterns under different stress conditions.TdGASA2 expression showed a consistent increase after wounding,methyl jasmonate(MeJA),and ethylene(ETP)treatments,peaking after 12-24 h for MeJA and ETP and after 1 h for pathogen elicitor(PA)treatment.Optimal expression conditions were determined,and the protein was successfully purified with a molecular weight of approximately 10 kDa.In vitro experiments demonstrated the potent antimicrobial activity of TdGASA2 against a range of pathogens,surpassing the efficacy of kanamycin.Minimum inhibitory concentration(MIC)and minimum bactericidal concentration(MBC)values confirmed its bactericidal and bacteriostatic activity against various bacteria.Time-kill assays also highlighted its efficacy against Listeria monocytogenes and Salmonella enterica,underscoring its potential as a therapeutic agent.Additionally,TdGASA2 exhibited superior DPPH radical-scavenging activity compared to ascorbic acid,indicating its potential as a natural antioxidant.In situ experiments revealed dose-dependent effects of TdGASA2 treatment on microbial growth in cheese,suggesting its efficacy as a preserva-tive to extend shelf life and enhance food safety.These findings underscore TdGASA2’s multifaceted potential in both antimicrobial and antioxidant applications,positioning it as a promising candidate for food preservation and health promotion. 展开更多
关键词 Host defense responses Gene expression Bactericidal effect Shelf-life extension Cheese spoilage
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Polyurethane Composites Synthesized Using Natural Oil-Based Polyols and Sisal Fibe 被引量:1
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作者 S.Michalowski M.A.Mosiewicki +2 位作者 M.Kuran´ska M.I.Aranguren A.Prociak 《Journal of Renewable Materials》 SCIE 2018年第4期426-437,共12页
Elastomeric polyurethanes were prepared from a reference polyurethane system modified with biobased polyols synthesized using rapeseed or palm oils.The reference material was modified by replacement of the commercial ... Elastomeric polyurethanes were prepared from a reference polyurethane system modified with biobased polyols synthesized using rapeseed or palm oils.The reference material was modified by replacement of the commercial polyol by 10%of biopolyols and also by addition of sisal fibers up to 5 wt%.The higher functionality of the biopolyols increased the crosslinking density of the networks and this was reflected by an increase in hardness and a decrease in water absorption.The effect of the sisal fibers mainly improved the mechanical and thermomechanical properties of the system with rapeseed oil because of good dispersion and strong fiber-matrix interaction.The system containing palm oil polyol corresponded to an initial formulation of high viscosity and,consequently,the resulting composites presented lower densities than the theoretically expected ones.These results are associated with fiber dispersion problems in the initial reactive mixture. 展开更多
关键词 Biopolyols PALM OIL RAPESEED OIL polyurethane composites
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Single-run reversed-phase HPLC method for determining sertraline content,enantiomeric purity,and related substances in drug substance and finished product 被引量:1
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作者 Alessia Rosetti Rosella Ferretti +3 位作者 Leo Zanitti Adriano Casulli Claudio Villani Roberto Cirilli 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2020年第6期610-616,共7页
A direct enantio-,diastereo-,and chemo-selective high-performance liquid chromatographic method was developed for determining the content,enantiomeric purity,and related substances of the chiral antidepressant drug se... A direct enantio-,diastereo-,and chemo-selective high-performance liquid chromatographic method was developed for determining the content,enantiomeric purity,and related substances of the chiral antidepressant drug sertraline HCl in a single chromatographic run.The separation was achieved on a chiral stationary phase based on amylose tris(3-chloro-5-methylphenylcarbamate)under reversed-phase conditions.The method was optimized by evaluating the influence of the temperature and mobile phase composition on the retention and selectivity.The application of the single-run approach allowed to baseline resolve all investigated species in less than 15 min,without using buffers or tandem-coupled columns.The chromatographic method was validated according to the guidelines of the Official Medicines Control Laboratory and applied to control the content of sertraline HCl and related chiral substances in a generic antidepressant formulation. 展开更多
关键词 Chiralpak IG-3 ENANTIOMERS DIASTEREOMERS Reversed-phase enantioselective HPLC Sertraline HCl
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Targeting Alzheimer’s disease via phytochemicals from Artemisia campestris L.:GC/MS analysis with an integrated computational approach
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作者 Nafila Zouaghi Elhafnaoui Lanez +11 位作者 Mohammed Larbi Benamor Salah Neghmouche Nacer Touhami Lanez Yahia Bekkar Habiba Haddad Khairallah Al-Abdallat Malek Zihlif Yahya Al-Abdallat Majd MAlsaleh Boubekeur Nadjemi Ahmad Telfah Stefania Garzoli 《Food Bioscience》 2026年第1期1079-1096,共18页
Alzheimer’s disease(AD)is a multifactorial neurodegenerative disorder requiring multi-target therapeutic strategies.In this study,phytochemicals from Artemisia campestris L.,an ethnomedicinal plant native to Algeria,... Alzheimer’s disease(AD)is a multifactorial neurodegenerative disorder requiring multi-target therapeutic strategies.In this study,phytochemicals from Artemisia campestris L.,an ethnomedicinal plant native to Algeria,were evaluated as potential multitarget ligands against five AD-relevant proteins:acetylcholinesterase(AChE),butyrylcholinesterase(BuChE),monoamine oxidase-B(MAO-B),β-secretase-1(BACE-1),and glycogen synthase kinase 3β(GSK-3β),chosen for their roles in neurotransmission,amyloid processing,tau pathology,and oxidative stress.Molecular docking was performed using Glide XP,followed by ADMET prediction,100-ns molecular dynamics simulations,MM-GBSA binding energy calculations,and DFT analysis.Among 25 compounds,dihydroartemisinic acid(C2)and ar-turmerone(C8)exhibited consistently stronger binding energies and higher dynamic stability across multiple targets compared with other constituents.These findings identify C2 and C8 as computationally predicted multitarget candidates that warrant experimental validation through in vitro enzyme inhibition and in vivo pharmacological studies. 展开更多
关键词 Quantum chemistry Molecular docking Molecular dynamics simulation ADMET prediction MM-GBSA binding energy
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Synthetic Receptors Decorated on Nanoparticles for Selective and Sensitive Glyphosate Detection
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作者 Ilgım GOKTURK Mamajan OVEZOVA +3 位作者 Gaye Ezgi YILMAZ Deniz TURKMEN Fatma YILMAZ Adil DENIZLI 《Photonic Sensors》 2025年第3期15-31,共17页
Herein,an innovative glyphosate imprinted poly(hydroxyethyl) methacrylateN-methacroyl-(L)-phenylalanine methyl ester nanoparticles(MIP@NPs)based plasmonic nanosensor featured with high sensitivity and selectivity was ... Herein,an innovative glyphosate imprinted poly(hydroxyethyl) methacrylateN-methacroyl-(L)-phenylalanine methyl ester nanoparticles(MIP@NPs)based plasmonic nanosensor featured with high sensitivity and selectivity was constructed by using the molecular imprinting technique and used for real-time glyphosate detection.The characterization of nanoparticles was performed by the nano Zetasizer and scanning electron microscopy(SEM),while nanosensors were characterized by the Fourier transform infrared-attenuated total reflection(FTIR-ATR)and contact angle measurement.Control experiments were conducted to evaluate the imprinting efficiency on the signal response using a non-imprinted surface plasmon resonance(NIP SPR)nanosensor prepared without adding glyphosate pesticide into the polymerization mixture.The MIP@NPs integrated molecularly imprinted surface plasmon resonance(MIP SPR)nanosensor having synthetic molecular recognition elements yielded a novel biosensing platform for label-free detection and real-time monitoring of glyphosate pesticide.The MIP SPR nanosensor detected the target glyphosate molecule 4.950 times more selectively than the competitor molecule malathion while 3.918 times more selectively than the competitor molecule malaoxon.In addition,the imprinting efficiency factor was found to be 6.76,indicating that the molecular imprinting process was successful.In addition,the imprinting factor was found to be 6.76.Kinetic studies and adsorption characteristics of glycosate adsorption were carried out to assess adsorption dynamics.The linear concentration range for glyphosate detection was 0.001 ppm−10.000 ppm of pesticide,and the detection limit was found to be 0.120 ppb.Studies on the repeatability of the MIP SPR nanosensor revealed that even after five cycles,the signal response for glyphosate detection did not change significantly with relative standard deviation,RSD<1.5 value.The artificial urine selected as the real sample was spiked with glyphosate at a final concentration of 10.000 ppm to evaluate the matrix effect,and the glyphosate amount was reported. 展开更多
关键词 N-methacroyl-(L)-phenylalanine methyl ester molecular imprinting GLYPHOSATE PESTICIDE surface plasmon resonance
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Epoxy Resins Modified with Vegetable Oils
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作者 P.Czub 《复旦学报(自然科学版)》 CAS CSCD 北大核心 2007年第5期606-,共1页
1 Results The application of modified natural oils, nontoxic, biodegradable and renewable materials, for the modification and the synthesis of epoxy resins were presented. Firstly, the application of epoxidized vegeta... 1 Results The application of modified natural oils, nontoxic, biodegradable and renewable materials, for the modification and the synthesis of epoxy resins were presented. Firstly, the application of epoxidized vegetable oils (soybean, rapeseed, linseed and sunflower):as reactive diluents for epoxy resins was proposed and studied[1-2]. Viscosity reducing ability of epoxidized oils was tested in the compositions with Bisphenol A based low-molecular-weight epoxy resins. The rheological behaviour of the mi... 展开更多
关键词 vegetable oils epoxy resins MODIFICATION mechanical and thermal properties
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