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Pressure-induced evolution of stoichiometries and electronic structures of host-guest Na-B compounds

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Matter and Radiation at Extremes 2023年第6期8卷 101-110页

作者： Zixuan Guo Xing Li Aitor Bergara Shicong Ding Xiaohua Zhang Guochun Yang State Key Laboratory of Metastable Materials Science&Technology and Key Laboratory for Microstructural Material Physics of Hebei Province School of ScienceYanshan UniversityQinhuangdao 066004China Departamento de Física and EHU-Quantum Center Universidad del País Vasco-Euskal Herriko UnibertsitateaUPV/EHU48080 BilbaoSpain Donostia International Physics Center(DIPC) 20018 DonostiaSpain Centro de Física de Materiales CFM Centro Mixto CSIC-UPV/EHU20018 DonostiaSpain

Superionic and electride behaviors in materials,which induce a variety of exotic physical properties of ions and electrons,are of great importance both in fundamental research and for practical applications.However,their coexistence in hot alkali-metal borides has not been observed.In this work,we apply first-principles structure search calculations to identify eight Na-B compounds with host-guest structures,which exhibit a wide range of building blocks and interesting properties linked to the Na/B composition.Among the known borides,Na-rich Na9B stands out as the composition with the highest alkali-metal content,featuring vertex-and face-sharing BNa16 polyhedra.Notably,it exhibits electride characteristics and transforms into a superionic electride at 200 GPa and 2000 K,displaying unusual Na atomic diffusion behavior attributed to the modulation of the interstitial anion electrons.It demonstrates semiconductor behavior in the solid state,and metallic properties associated with Na 3p/3s states in the superionic and liquid regions.On the other hand,B-rich NaB7,consisting of a unique covalent B framework,is predicted to exhibit low-frequency phonon-mediated superconductivity with a T_(c) of 16.8 K at 55 GPa.Our work advances the understanding of the structures and properties of alkali-metal borides.

关键词： alkali structures compounds

Simple identification approach for trace heteroatom-containing compounds in petroleum fraction by Automated Mass Spectral Deconvolution and Identification System

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色谱 2016年第9期34卷 925-932页

作者： Nagy E. MOUSTAFA KoutEl-Kloub FarsMAHMOUD Institute of Inorganic and Analytical Chemistry University of Münster Department of Chemistry Women’s College for ArtsScience and EducationAin Shams University

Here we present a simple yet effective gas chromatography-mass spectrometry （GC-MS） identification approach for the detection of heteroatom-containing compounds （HACCs） in petroleum fractions. The MS/ AMDIS （Automated Mass Spectral Deconvolution and Identification System） program was used to identify parts per million （ppm） HACC concentrations in petroleum fractions in place of traditional techniques （extraction and standard injection）. Polycyclic aromatic sulfur heterocycles （S-PAHs） were used as model compounds to confirm the validity of the AMDIS identifiers, which were compared with extracted results using the off-line X- calibur software. AMDIS was able to identify ppm concentrations of S-PAHs in oil condensate. There was good agreement between experimental and AMDIS identification results for S-PAHs in oil condensate. AMDIS was also used to detect nitrogen-containing compounds （NCCs） and alkylphenols in oil condensate. Our results confirmed the presence of 2-methylbenzothiazole, carbazole, and 2,4-ditertbutyl phenol. In a crude oil sample, AMDIS identification of m/z = 191 biomarkers wa s consistent with empirical results. Therefore, AMDIS can help to reduce the number of experimental steps in identification protocols.

关键词： Automated Mass Spectral Deconvolution and Identification System (AMDIS) heteroatom-containing compounds petroleum identification

Ultrasound-assisted extraction of antioxidant polyphenolic compounds from Nephelium lappaceum L.(Mexican variety) husk

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Asian Pacific Journal of Tropical Medicine 2018年第12期11卷 676-681页

作者： Adriana Méndez-Flores Ayerim Hérnandez-Almanza Aidé Sáenz-Galindo Jesús Morlett-Chávez Cristóbal N Aguilar Juan Ascacio-Valdés Bioprocesses and Bioproducts Research Group Food Research Department School of Chemistry Autonomous University of Coahuila Organic Chemistry Department School of Chemistry Autonomous University of Coahuila Molecular Biology Laboratory School of Chemistry Autonomous University of Coahuila

Objective: To reach the recovery and identification of antioxidant polyphenolic compounds from Nephelium lappaceum L.(Mexican variety) husk using ultrasound-assisted extraction and liquid chromatography/mass spectrometry as well as the in vitro antioxidant activity. Methods: Rambutan husk extracts were obtained by ultrasound-assisted extraction, mass/volume ratio, water/ethanol percentage and extraction time were evaluated. Once the best extraction condition of polyphenolic compounds was defined, a polyphenolic fraction was recovered using Ambetlite XAD-16. The total content of antioxidant polyphenolic compounds was determined by summation of the total hydrolysable polyphenol and total condensed polyphenol contents. Recovered compounds were identified by FTIR(ATR) spectroscopy and HPLC/ESI/MS. The antioxidant activity was carried out by ABTS, DPPH and lipid oxidation inhibition in vitro methods. Results: In Mexican variety rambutan husk, the total polyphenolic content was 487.67 mg/g, after ultrasound-assisted extraction. According to the HPLC/ESI/MS analysis 12 antioxidant polyphenolic compounds were identified, mostly ellagitannins such as geraniin, corilagin and ellagic acid. The antioxidant activity determined by ABTS, DPPH and lipid oxidation inhibition methods was demonstrated. The main functional groups of the identified compounds were determined by FTIR analysis. Conclusions: It was demonstrated that ultrasound-assisted extraction was effective and allowed the extraction and recovery of antioxidant polyphenolic compounds. Furthermore Mexican variety rambutan husk is an important source for recovering polyphenolic compounds with antioxidant activity, these compounds have potential application for the treatment/prevention of various diseases related to cancer and pathogenic microorganisms.

关键词： Mexican variety rambutan Ultra-sound assisted extraction Antioxidant polyphenolic compounds HPLC/ESI/MS

Clinical characteristics and treatment compounds of obesity-related kidney injury

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World Journal of Diabetes 2024年第6期15卷 1091-1110页

作者： Tuo-Hua Mao Han-Qi Huang Chuan-Hai Zhang Department of Endocrinology Renmin Hospital of Wuhan UniversityWuhan 430060Hubei ProvinceChina Department of Endocrinology Hubei No.3 People’s Hospital of Jianghan UniversityWuhan 430033Hubei ProvinceChina Department of Physiology UT Southwestern Medical CenterDallasTX 75390United States

Disorders in energy homeostasis can lead to various metabolic diseases,particularly obesity.The obesity epidemic has led to an increased incidence of obesityrelated nephropathy(ORN),a distinct entity characterized by proteinuria,glomerulomegaly,progressive glomerulosclerosis,and renal function decline.Obesity and its associated renal damage are common in clinical practice,and their incidence is increasing and attracting great attention.There is a great need to identify safe and effective therapeutic modalities,and therapeutics using chemical compounds and natural products are receiving increasing attention.However,the summary is lacking about the specific effects and mechanisms of action of compounds in the treatment of ORN.In this review,we summarize the important clinical features and compound treatment strategies for obesity and obesityinduced kidney injury.We also summarize the pathologic and clinical features of ORN as well as its pathogenesis and potential therapeutics targeting renal inflammation,oxidative stress,insulin resistance,fibrosis,kidney lipid accumulation,and dysregulated autophagy.In addition,detailed information on natural and synthetic compounds used for the treatment of obesity-related kidney disease is summarized.The synthesis of detailed information aims to contribute to a deeper understanding of the clinical treatment modalities for obesity-related kidney diseases,fostering the anticipation of novel insights in this domain.

关键词： compounds Obesity Kidney injury Obesity-related nephropathy Clinical features and treatment

First Principles Study on the Stability and Mechanical Properties of MB (M=V, Nb and Ta) compounds

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Chinese Physics Letters 2013年第11期30卷 144-148页

作者：漆晨进冯晶周荣峰蒋业华周荣 Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093 School of Engineering and Applied Science Harvard UniversityCambridgeMA 02138USA

The first principles calculations based on density functional theory are performed to investigate the stability,chemical bonding,elastic constants,hardness and Debye temperature of MB(M=V,Nb and Ta)compounds.The structures of these borides are optimized,and the lattice parameters are in good agreement with the experimental data.The calculated cohesive energy and formation enthalpy indicate that they are of a thermodynamically stable structure.The mechanical properties,including elastic constants Cij,bulk modulus,Young's modulus,shear modulus and Poisson's ratio,are calculated.The bulk moduli of them ranging from 263.0 to 278.4 GPa are larger than many common Laves phases and TaB with 278.4 GPa being the largest bulk modulus value among them.The population analysis is used to analyze the chemical bonds in these compounds.The hardness of the compounds is also evaluated,and the result reveals that TaB is the hardest compound among them.The Debye temperature of MB is calculated.The results show that the values of MB compounds range from 419.3 to 794.3 K.

关键词： compounds structure modulus

Isolation and Structural Speculation of Herbicide-Active compounds from the Metabolites of Pythium aphanidermatum

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Journal of Integrative Agriculture 2013年第6期12卷 1026-1032页

作者： ZHANG Li-hui ZHANG Jin-lin LIU Ying-chao CAO Zhi-yan HAN Jian-min YANG Juan DONG Jin-gao Mycotoxin and Molecular Plant Pathology Lab Agricultural University of Hebei

Natural herbicides, or environment-friendly bioherbicides have been attracted more and more attentions. Isolation and structural identification of natural herbicide-active compounds from plant pathogens has been proved to be an effective approach for novel lead discovery of the pesticide development. In this study, the metabolites of the mutant strain PAM1, which obtained from PA1 of Pythium aphanidermatum （Eds.） Fitzp by ultraviolet radiation were separated and identified by HPLC, NMR, and IR. The results revealed that three active compounds including 4-hydroxy-3-methoxycinnamic acid and two indole derivatives, exhibited inhibition activity on the elongation of radical and coleoptile of Digtaria sanguinalis （L.） Scop.

关键词： herbicidal principles compounds P. aphanidermatum

Fluid Catalytic Cracking Feed Hydrotreatment and its Impact on Distribution of Sulfur and Nitrogen compounds in FCC Diesel

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China Petroleum Processing & Petrochemical Technology 2015年第1期17卷 69-74页

作者： Bai Rui Chai Yongming Zhang Chengtao Liu Chenguang State Key Laboratory of Heavy Oil Processing College of Chemical Engineering China University of Petroleum (East China) Hainan Petrochemical Company Ltd.SINOPEC

The sulfides and nitrogen compounds in FCC diesel were analyzed by gas chromatography equipped with a pulsed flame photometric detector(GC-PFPD) and gas chromatography coupled with nitrogen chemiluminescence detection(GC-NCD). And the variation of sulfides and nitrogen compounds in FCC diesel produced from gas oil feed hydrotreated at different temperatures was investigated. The test results showed that two main types of sulfur compounds, i.e. benzothiophenes(BTs) and dibenzothiophenes(DBTs) were found in diesel. Nitrogen compounds are mainly composed of non-basic nitrogen compounds, and indoles and carbazoles account for about 98% of the total nitrogen contents. The sulfides in FCC diesel obtained from hydrotreated feed are mainly BTs with a small amount of 4-MDBT and 4,6-DMDBT. With the increase in FCC feed hydrotreating temperature, indoles content in FCC diesel increases, while carbazoles content decreases.

关键词： GC-PFPD GC-NCD pre-hydrotreating sulfides nitrogen compounds diesel

Phenolic compounds affect production of pyocyanin, swarming motility and biofilm formation of Pseudomonas aeruginosa

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Asian Pacific Journal of Tropical Biomedicine 2016年第8期6卷 698-701页

作者： Aylin Ugurlu Aysegul Karahasan Yagci Seyhan Ulusoy Burak Aksu Gulgun Bosgelmez-Tinaz Department of Microbiology School of Medicine Marmara University Department of Biology Faculty of Arts and Sciences Süleyman Demirel University Department of Basic Pharmaceutical Sciences Faculty of Pharmacy Marmara University

Objective: To investigate the effects of plant-derived phenolic compounds(i.e. caffeic acid, cinnamic acid, ferulic acid and vanillic acid) on the production of quorum sensing regulated virulence factors such as pyocyanin, biofilm formation and swarming motility of Pseudomonas aeruginosa(P. aeruginosa) isolates.Methods: Fourteen clinical P. aeruginosa isolates obtained from urine samples and P. aeruginosa PA01 strain were included in the study. The antibacterial effects of phenolic compounds were screened by well diffusion assay. Pyocyanin and biofilm activity were measured from culture supernatants and the absorbance values were measured using a spectrophotometer. Swarming plates supplemented with phenolic acids were point inoculated with P. aeruginosa strains and the ability to swarm was determined by measuring the distance of swarming from the central inoculation site.Results: Tested phenolic compounds reduced the production of pyocyanin and biofilm formation without affecting growth compared to untreated cultures. Moreover, these compounds blocked about 50% of biofilm production and swarming motility in P. aeruginosa isolates.Conclusions: We may suggest that if swarming and consecutive biofilm formation could be inhibited by the natural products as shown in our study, the bacteria could not attach to the surfaces and produce chronic infections. Antimicrobials and natural products could be combined and the dosage of antimicrobials could be reduced to overcome antimicrobial resistance and drug side effects.

关键词： Quorum sensing Phenolic compounds Pseudomonas aeruginosa Biofilm Swarming

Antimicrobial Activity of the Methanolic Extract and compounds from the Stem Bark of Drypetes tessmanniana

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Chinese Journal of Integrative Medicine 2010年第4期16卷 337-343页

作者： Victor Kuete Marlise D.J.Dongfack Armelle T.Mbaveng Marie-Christine Lallemand Hanh T.Van-Dufat Jean-Duplex Wansi Elisabeth Seguin Francois Tillequin Jean Wandji Department of Biochemistry Faculty of ScienceUniversity of Dschang.P.O.Box 67 DschangCameroon Department of Organic Chemistry Faculty of ScienceUniversity of Yaounde I.P.O.Box 812 YaoundeCameroon Laboratoire de Pharmacognosie de I'Universite Paris Descartes UMR/CNRS N° 8638Faculte des Sciences Biologiques et Pharmaceutiques4-Avenue de I'Observatoire75006 ParisFrance Department of Biochemistry Faculty of ScienceUniversity of Yaounde IP.O.Box 812 YaoundeCameroon Department of Chemistry University of DoualaFaculty of ScienceP.O.Box 24157 DoualaCameroon Laboratoire de Pharmacognosie UFR de Medecine Pharmacie Rouen22-Bid Gambetta76183 Rouen Cedex 1France

Objective： To evaluate the antimicrobial activity of the methanol extract from the stem bark of Drypetes tessmanniana, fractions （DTB1-5） as well as compounds [friedelin （2）, 3,7-dioxofriedelane （3）, 3,15-dioxofriedelane （4）, 313 -O-（E）-3,5-dihydroxycinnamoyl-11 -oxo-olean-12-ene （6）, and 313,6 α -dihydroxylup- 20（29）-ene （7）. Methods： Agar disc diffusion was used to determine the sensitivity of the above samples, whilst the microdilution method was used for the determination of the minimal inhibitory concentration （MIC） and the minimal microbicidal concentrations （MMC）. Results： The diffusion test showed that the crude extract was able to prevent the growth of all tested organisms. All other samples showed selective activity. The inhibitory effect of the fraction DTB2 was noted on 63.7%, that of DTB1 and DBT3 on 54.6%, whilst DTB4 and DTB5 were active on 9.1% of the 11 tested organisms. The tested compounds prevented the growth of 81.8% of the tested microbial species for compounds 3 and 4, 36.7% for compound 6, and 18.2% for compound 7. The results of the MIC determinations indicated perceptible values for DTB and compound 4 on 81.8% of the tested organisms. For other samples, MICs were detected on 0-63.7%. The lowest MIC value （78.12 μg/mL） for the crude extract and fractions （DTB2） was observed on M. audouinii. The corresponding value for isolated compounds （156.25 μg/ mL） was noted with compounds 3 on S. faecalis and 4 on M. audouinii. The results of the MMC determination suggested that the microbicidal effect of most of the tested samples on the studied microorganisms could be expected. Conclusion： The methanol extract from the stem bark of Drypetes. tessmanniana （Euphorbiaceae） as well as some of the isolated compounds might be potential sources of new antimicrobial drues.

关键词： Drypetes tessmanniana Euphorbiaceae compounds antimicrobial activity