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High-Resolution Mass Spectroscopy for Revealing the Charge Storage Mechanism in Batteries: Oxamide Materials as an Example
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作者 Chenyang Zhang Yuan Chen +7 位作者 Kun Fan Guoqun Zhang Jincheng Zou Huichao Dai Yanbo Gao Xiaobo Wang Minglei Mao Chengliang Wang 《Energy & Environmental Materials》 SCIE EI CAS CSCD 2023年第4期195-202,共8页
The pursuit of high-performance electrode materials is highly desired to meet the demand of batteries with high energy and power density.However,a deep understanding of the charge storage mechanism is always challengi... The pursuit of high-performance electrode materials is highly desired to meet the demand of batteries with high energy and power density.However,a deep understanding of the charge storage mechanism is always challenging,which limits the development of advanced electrode materials.Herein,high-resolution mass spectroscopy(HR-MS)is employed to detect the evolution of organic electrode materials during the redox process and reveal the charge storage mechanism,by using small molecular oxamides as an example,which have ortho-carbonyls and are therefore potential electrochemical active materials for batteries.The HR-MS results adequately proved that the oxamides could reversibly store lithium ions in the voltage window of 1.5–3.8 V.Upon deeper reduction,the oxamides would decompose due to the cleavage of the C–N bonds in oxamide structures,which could be proved by the fragments detected by HR-MS,^(1)H NMR,and the generation of NH_(3)after the reduction of oxamide by Li.This work provides a strategy to deeply understand the charge storage mechanism of organic electrode materials and will stimulate the further development of characterization techniques to reveal the charge storage mechanism for developing high-performance electrode materials. 展开更多
关键词 charge storage mechanism high-resolution mass spectroscopy organic batteries organic electrodes oxamides
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Super Antibiotics, Part II. Hyperforin, Mass Spectroscopy (MS) and Gas Chromatography-Mass Spectrometry (GC-MS), Evidence of Permeability of the Blood-Testis Barrier (BTB) and the Blood-Brain Barrier (BBB) to Hyperforin 被引量:2
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作者 Ilia Brondz 《International Journal of Analytical Mass Spectrometry and Chromatography》 2016年第4期66-73,共8页
In the first article of this series, we presented some evidence of hyperforin as an antibiotic, antiprotozoal, antiviral, anticancer, and immunomodulatory substance. In the present article, evidence of the permeabilit... In the first article of this series, we presented some evidence of hyperforin as an antibiotic, antiprotozoal, antiviral, anticancer, and immunomodulatory substance. In the present article, evidence of the permeability of the blood-testis barrier (BTB) and blood-brain barrier (BBB) to hyperforin and its distribution in other organs of the domestic pig (Sus scrofa domesticus) are revealed. Seven-month-old male boars with a body mass of 100 kg were fed a diet containing hyperforin. Organs were surgically removed under anesthesia. Organs were suitable prepared and extracted, and then analyzed using gas chromatography-mass spectrometry with supersonic molecular beams (GC-MS with SMB). The presence of hyperforin was recorded in all organs and body fluids. Special attention was paid to the evaluation of the presence of hyperforin in the brain and testes of experimental animals. The presence of hyperforin in the brain and testes of experimental animals was established by GC-MS with SMB. The results are of interest because penicillin and numerous other antibiotics cannot pass through the BTB or BBB if healthy or non-inflamed, which limits their use in patients with meningitis and gonorrhea. The findings are also of interest in cases of penicillin- and multi-antibiotic-resistant bacterial infections. 展开更多
关键词 ANTIBIOTICS HYPERFORIN Super antibiotic mass spectroscopy Gas Chromatography-mass Spectrometry Blood-Testis Barrier Blood-Brain Barrier Methicillin-Resistant Staphylococcus aureus (MRSA)
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Temporal and spatial study of differently charged ions emitted by ns-laser-produced tungsten plasmas using time-of-flight mass spectroscopy
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作者 吴鼎 George C-Y CHAN +4 位作者 毛向雷 李裕 Richard E RUSSO 丁洪斌 Vassilia ZORBA 《Plasma Science and Technology》 SCIE EI CAS CSCD 2021年第9期176-183,共8页
Tungsten(W)is an important material in tokamak walls and divertors.The W ion charge state distribution and the dynamic behavior of ions play important roles in the investigation of plasma–wall interactions using lase... Tungsten(W)is an important material in tokamak walls and divertors.The W ion charge state distribution and the dynamic behavior of ions play important roles in the investigation of plasma–wall interactions using laser-ablation-based diagnostics such as laser-induced breakdown spectroscopy and laser-induced ablation spectroscopy.In this work,we investigate the temporal and spatial evolutions of differently charged ions in a nanosecond-laser-produced W plasma in vacuum using time-of-flight mass spectroscopy.Ions with different charge states from 1 to 7(W+to W7+)are all observed.The temporal evolutions of the differently charged ions show that ions with higher charge states have higher velocities,indicating that space separation occurs between the differently charged ion groups.Spatially-resolved mass spectroscopy measurements further demonstrate the separation phenomenon.The temporal profile can be accurately fitted by a shifted Maxwell–Boltzmann distribution,and the velocities of the differently charged ions are also obtained from the fittings.It is found that the ion velocities increase continuously from the measured position of 0.75 cm to 2.25 cm away from the target surface,which indicates that the acceleration process lasts through the period of plasma expansion.The acceleration and space separation of the differently charged ions confirm that there is a dynamic plasma sheath in the laser-produced plasma,which provides essential information for the theoretical laser-ablation model with plasma formation and expansion. 展开更多
关键词 laser ablation temporal and spatial evolution time-of-flight mass spectroscopy spatial separation differently charged ions
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Noninvasive Detection of the Gases Inside the Sealed Batteries by the On-line Mass Spectrometry
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作者 XiaoRongZHOU PeiFangLIU LinZHUANG JunTaoLU 《Chinese Chemical Letters》 SCIE CAS CSCD 2004年第7期823-826,共4页
关键词 mass spectroscopy gas evolution BATTERIES OVERCHARGE noninvasive.
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Probing the degradation of pharmaceuticals in urine using MFC and studying their removal efficiency by UPLC-MS/MS 被引量:2
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作者 Priya Sharma Devendra Kumar Srikanth Mutnuri 《Journal of Pharmaceutical Analysis》 SCIE CAS CSCD 2021年第3期320-329,共10页
Nutrient recovery from source-separated human urine has attracted interest as it is rich in nitrogen and phosphorus that can be utilized as fertilizer.However,urine also contains pharmaceuticals,steroid hormones,etc.a... Nutrient recovery from source-separated human urine has attracted interest as it is rich in nitrogen and phosphorus that can be utilized as fertilizer.However,urine also contains pharmaceuticals,steroid hormones,etc.and their removal is crucial as they have detrimental effects on the environment and human health.The current study focuses on investigating the degradation of pharmaceuticals using a double-chamber microbial fuel cell(MFC).Urine was spiked with four pharmaceuticals(trimethoprim,lamivudine,levofloxacin,and estrone)at a concentration of 2 mg/mL.The MFC was operated for 7 months in batch mode with this spiked urine as feed.The degradation efficiency of the MFC was studied,for which a selective liquid chromatography-tandem mass-spectrometric method was developed for the quantitation of compounds used in the spiking experiments and was validated with a lower limit of quantification of 0.39 ng/mL.The maximum removal rate achieved was 96%±2%.The degradation mechanism involved processes like sorption and anoxic biodegradation.The voltage curve obtained showed that the presence of pharmaceuticals had an initial negative impact on power generation along with increased organic content;however,after the reactor acclimatization,increased power output was achieved with maximum organics removal at 30 h of retention time.This work opens a new perspective for the anoxic biodegradation of pharmaceuticals and can be useful in future bioremediation studies. 展开更多
关键词 Pharmaceuticals URINE MFC BIODEGRADATION Liquid chromatography mass spectroscopy
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Pulmonary alveolar proteinosis complicated with nocardiosis: A case report and review of the literature 被引量:2
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作者 Xiao-Kang Wu Quan Lin 《World Journal of Clinical Cases》 SCIE 2021年第12期2874-2883,共10页
BACKGROUND Pulmonary alveolar proteinosis(PAP)is a pulmonary syndrome wherein large volumes of phospholipid and protein-rich surfactants accumulate within the alveoli.PAP forms include primary(auto-immune PAP),seconda... BACKGROUND Pulmonary alveolar proteinosis(PAP)is a pulmonary syndrome wherein large volumes of phospholipid and protein-rich surfactants accumulate within the alveoli.PAP forms include primary(auto-immune PAP),secondary,and congenital.Nocardiosis is a form of suppurative disease induced upon infection with bacteria of the Nocardia genus.Clinically,cases of PAP complicated with Nocardia infections are rare,regardless of form.Unfortunately,as such,they are easily overlooked or misdiagnosed.We describe,here,the case of a patient suffering from simultaneous primary PAP and nocardiosis.CASE SUMMARY A 45-year-old Chinese man,without history of relevant disease,was admitted to our hospital on August 8,2018 to address complaints of activity-related respiratory exertion and cough lasting over 6 mo.Lung computed tomography(CT)revealed diffuse bilateral lung infiltration with local consolidation in the middle right lung lobe.Subsequent transbronchial lung biopsy and CT-guided lung biopsy led to a diagnosis of primary PAP(granulocyte-macrophage colonystimulating factor antibody-positive)complicated with nocardiosis(periodic acid-Schiff-positive).After a 6 mo course of anti-infective treatment(sulfamethoxazole),the lesion was completely absorbed,such that only fibrous foci remained,and the patient exhibited significant symptom improvement.Followup also showed improvement in pulmonary function and the CT imaging findings of PAP.No whole-lung lavage has been conducted to date.This case highlights that active anti-nocardia treatment may effectively improve the symptoms and alleviate PAP in patients with PAP and nocardia,possibly reducing the need for whole-lung lavage.CONCLUSION When evaluating patients presenting with PAP and pulmonary infections, thepotential for nocardiosis should be considered. 展开更多
关键词 Pulmonary alveolar proteinosis NOCARDIOSIS Vitek mass spectroscopy Whole-lung lavage Case report
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Quantitative analysis of catechins in Saraca asoca and correlation with antimicrobial activity 被引量:1
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作者 Amey Shirolkar Anjum Gahlaut +1 位作者 Anil K.Chhillar Rajesh Dabur 《Journal of Pharmaceutical Analysis》 SCIE CAS 2013年第6期421-428,共8页
Herbal medicines are highly complex and have unknown mechanisms in diseases treatment. Saraca asoca (Roxb.), De. Wild has been recommended to treat gynecological disorders and used in several commercial polyherbal f... Herbal medicines are highly complex and have unknown mechanisms in diseases treatment. Saraca asoca (Roxb.), De. Wild has been recommended to treat gynecological disorders and used in several commercial polyherbal formulations. In present study, efforts have been made to explore antimicrobial activity and its co-relation with the distributions of catechins in the organs of S. asoca using targeted MS/MS. Eight extracts (cold and hot water) from four different organs of S. asoca and two drugs were prepared and antimicrobial activity was assessed by microbroth dilution assay. Quantitative and qualitative analysis of catechins in crude extracts was done by using targeted and auto-MS/MS and correlated with antimicrobial activity. (+)-Catechin and (+)- epicatechin and their biosynthesis related compound were found to be up-regulated in regenerated bark and leaves extracts. (-)-Epigallocatechin was found to be significantly higher in bark water extract as compared to others but showed low antimicrobial activity. Result showed down- regulation of (-)-epigallocatechin and up-regulation of (+)-catechin and (+)-epicatechin in the regenerated bark and leaves of S. asoca. It might be the contributing factor in the antimicrobial activity of regenerated bark and leaves of the plant. The concentration of (+)-epicatechin in processed drugs (Ashokarishta) from Baidyanath was found to be seven times higher than that of Dabur Pvt. Ltd., but no antimicrobial activity was observed, indicating the variations among the plant based drugs. This will be helpful in rational use of S. asoca parts. Furthermore, the analyticalmethod developed is sensitive, repeatable and reliable; therefore, it is suitable for quality control of herbal drugs. 展开更多
关键词 mass spectroscopy PHYTOCHEMISTRY Quality control FLAVONOIDS AYURVEDA ANTIMICROBIAL
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Characterization and Quantification of Phenolic Compounds of Hydroethanolic Extracts and Fractions of Leaves Gnetum africanum (Welv.) and Gnetum buchholzianum (Engl.) (Gnetaceae) 被引量:1
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作者 Bertin Sone Enone Gisèle Marie-Marguerite Etame-Loe +13 位作者 Charles Christian Ngoule Jean-Pierre Ngene Juliette Koube Lahngong Methodius Shinyuy Simone Véronique Fannang Moïse Henri Julien Nko’o Jean Baptiste Hzounda Fokou Hans Denis Bamal Celestine Magne Valdi Steve Djova Wilfred Ndogmo Tekapi Sandrine Sikadeu Josiane Etang Albert Mouelle Sone 《Open Journal of Applied Sciences》 CAS 2022年第7期1304-1318,共15页
Research for bioactive molecules and not resistant to infectious agents remains topical for science. The total polyphenols (TPP) and total flavonoids (TFv) of the hydroethanolic extracts and fractions obtained were qu... Research for bioactive molecules and not resistant to infectious agents remains topical for science. The total polyphenols (TPP) and total flavonoids (TFv) of the hydroethanolic extracts and fractions obtained were quantified according to the spectrophotometric method described in the literature using the Folin-Ciocalteu reagent and the colorless solutions of sodium nitrite 2.5% and aluminum chloride 10% respectively. The characterization of chemical compounds was made by coupling liquid chromatography (LC) and mass spectroscopy (MS). Thus, 15 chemical compounds were characterized, seven from Gnetum africanum (EBa) and eight from Gnetum buchholzianum (EBb). The majority of which were stilbens, such as Gnetupendin D, Dimethoxygnetulin, Methoxyparvifolol D, Isorhaponcitin from Eba and Gnetuhaidin P, Gnetupendin D, Gnetuhainin C, phenols (Alcohol Homovanillyl, Alcohol Erythro guaiacylglycerol-β-O-4'-coniferyl, and Alcohol Homovanillyl from EBb. The minority were flavonoids such as Dimethoxydihydropyraneriodictyol, Dimethoxyeriodictyol (EBa) and Dimethoxydihydropyraneriodictyol, Trimethoxyluteolin (EBb). The levels of total polyphenolics and total flavonoids content were respectively 14.520 ± 0.557 mg EAA/g Extract and 29.870 ± 2.485 mg EQ/g Extract for EBa. The levels of total polyphenolics and total flavonoids content for EBb were respectively 4.560 ± 0.010 mg EAA/g Extract and 2.233 ± 0.251 mg EQ/g Extract. The high levels of flavonoids content respectively 220.200 ± 35.500 and 335.300 ± 57.810 mg EQ/g Extract were shown in Dichlorometan fraction from EBa and EBb. These bioactive compounds identified and total phenolics compounds quantified can be exploited in pharmacological and pharmacokinetical activities to fight against multi-resistant infectious agents and as well as oxidative stress and antiinflammatory diseases. 展开更多
关键词 Gnetum africanum Gnetum buchholzianum Phenolic Compounds Liquid Chromatography mass spectroscopy
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Characterization of deep acceptor level in as-grown ZnO thin film by molecular beam epitaxy
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作者 M.Asghar K.Mahmood +3 位作者 M.A.Hasan I.T.Ferguson R.Tsu M.Willander 《Chinese Physics B》 SCIE EI CAS CSCD 2014年第9期364-368,共5页
We report deep level transient spectroscopy results from ZnO layers grown on silicon by molecular beam epitaxy (MBE), The hot probe measurements reveal mixed conductivity in the as-grown ZnO layers, and the current-... We report deep level transient spectroscopy results from ZnO layers grown on silicon by molecular beam epitaxy (MBE), The hot probe measurements reveal mixed conductivity in the as-grown ZnO layers, and the current-voltage (l-V) measurements demonstrate a good quality p-type Schottky device. A new deep acceptor level is observed in the ZnO layer having activation energy of 0.49 ± 0.03 eV and capture cross-section of 8,57 ×10^-18 cm^2. Based on the results from Raman spectroscopy, photoluminescence, and secondary ion mass spectroscopy (SIMS) of the ZnO layer, the observed acceptor trap level is tentatively attributed to a nitrogen-zinc vacancy complex in ZnO, 展开更多
关键词 ZnO secondary ion mass spectroscopy PHOTOLUMINESCENCE Raman spectroscopy
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Model of Diffusion of Sulfur in Soda-lime-silicate Glass:An Experimental and Comparative Study
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作者 孟政 HONG Wang +1 位作者 WANG Yongbin JIANG Hong 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第1期76-79,共4页
The diffusion property of sulfur on the soda-lime-silicate float glass surface was studied by using secondary ion mass spectroscopy(SIMS).According to the Fick's Second Law,two models of diffusion of sulfur on the ... The diffusion property of sulfur on the soda-lime-silicate float glass surface was studied by using secondary ion mass spectroscopy(SIMS).According to the Fick's Second Law,two models of diffusion of sulfur on the glass surface were built.When the diffusion of sulfate(S^6+) is considered uniquely,the concentration-depth profile of sulfur can not be fitted very well,especially on the top surfaces of the air side and tin side of float glass.So the diffusion of sulfide(S^2-) on the profile of sulfur can not be ignored.The concentration-depth profile of sulfur on both sides of glass can be fitted more exactly when both S^6+ and S^2- are considerd.Based on the above-mentioned fitting results,it is concluded that the diffusion coefficents of S^6+ and S^2- of tin side are larger than those of the air side.Moreover,the diffusion coefficents are related to the contacted medium. 展开更多
关键词 DIFFUSION SULFUR soda-lime-silicate glass secondary ion mass spectroscopy
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Trials for Gathering Information on an Unknown Peak in the GC-MS Spectra of Horse and Pony Hair Extracts
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作者 Maia Tsikolia Till Opatz +5 位作者 Ulrich Kauhl Nurhayat Tabanca Betul Demirci Saundra H. TenBroeck Kenneth J. Linthicum Ulrich R. Bernier 《Advances in Entomology》 2021年第2期100-111,共12页
The volatile compounds from horse and pony hairs and skin were analyzed to determine bioactive molecules that are kairomones used for host location by blood-feeding diptera. In this study, horse and pony hair samples ... The volatile compounds from horse and pony hairs and skin were analyzed to determine bioactive molecules that are kairomones used for host location by blood-feeding diptera. In this study, horse and pony hair samples were extracted with organic solvents (pentane or hexane) and analyzed by gas chromatography-mass spectrometry analysis (GC-MS) with closed electron ionization (CEI). Using the GC-MS analysis, we observed a compound peak, which could not be identified by comparison to mass spectra in the mass spectral library. This unknown compound was often the largest peak in the chromatogram and had a retention index and mass spectral fragmentation similar to nonanal. However, there were several differences in the fragmentation pattern. When compared to a nonanal reference standard, it was evident that this was a different compound. Hydrodistillation of pony hair was another extraction method to obtain the unknown component in higher concentrations. Analysis of this extract with GC-flame ionization detector (FID) with GC-MS confirmed the same unknown peak. Further experiments and analysis with the various mass spectroscopy tools gave the possible molecular ion with mass-to-charge ratio (<em>m/z</em>) 142, corresponding to the unknown component. 展开更多
关键词 Nonanal Skin Emanation Insect Pests Equus caballus Equus ferus caballus mass spectroscopy Structure Elucidation
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Effects of Irrigation and Drought on Growth and Essential Oil Production in O. vulgare and R. officinalis
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作者 David C. Baudoin Edward Bush +2 位作者 Ted Gauthier Amy B. Hernandez Heather Kirk-Ballard 《American Journal of Plant Sciences》 2022年第5期659-667,共9页
The essential oil industry has led a rapidly growing market in American herbal medicine. The global essential oil industry was valued at an estimated 18.6 billion USD in 2020 and is expected to have a compound annual ... The essential oil industry has led a rapidly growing market in American herbal medicine. The global essential oil industry was valued at an estimated 18.6 billion USD in 2020 and is expected to have a compound annual growth rate of 7.6% from 2020 to 2027. “Essential oil” is a broad term used to describe volatile organic compounds (VOCs) that are often associated with a plant’s essence or aroma. These molecules are commonly extracted from a variety of different plant structures by steam distillation and cold pressing. Essential oils function as a defense against insects, bacteria, fungi, and other stressors, such as drought and cold. The most industrially important of this class of compounds are monoterpenes, steam-volatile constituents which are the most abundant terpenes throughout plants. Essential oils may include monoterpenes (two isoprene units), sesquiterpenes (three isoprene units), ketones, and phenolics. Phenolics include flavonoids, anthocyanins, and tannins. 展开更多
关键词 Water Relations Essential Oil Extraction TERPENES Plant Environmental Stress mass spectroscopy
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Investigation of L/D-threonine substituted L-serine octamer ions by mass spectrometry and infrared photodissociation spectroscopy 被引量:1
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作者 Juan Ren Yi-Yun Wang +1 位作者 Ru-Xia Fenga Xiang-Lei Kong 《Chinese Chemical Letters》 SCIE CAS CSCD 2017年第3期537-540,共4页
Threonine-substituted serine octamer ions were generated by electrospray ionization(ESI) and investigated by mass spectrometry and infrared photodissociation(IRPD) spectroscopy. IRPD spectra of[L-Ser_7+ L/D-Thr_1... Threonine-substituted serine octamer ions were generated by electrospray ionization(ESI) and investigated by mass spectrometry and infrared photodissociation(IRPD) spectroscopy. IRPD spectra of[L-Ser_7+ L/D-Thr_1]H~+and [L-Ser_6+ L/D-Thr_2]H~+were obtained in the range of 2700–3600 cm^(-1). Chiral differentiation was achieved by comparing their IRPD spectra. The main difference located in the range of 3300–3500 cm^(-1). And the results indicate the substitution of L-Ser by D-Thr could weaken the intermolecular H-bonds and loosen the original structures of serine octamers. 展开更多
关键词 IRPD spectroscopy Threonine Serine octamer Chiral differentiation mass spectrometry
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Proteomics techniques in protein biomarker discovery
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作者 Mahsa Babaei Soheila Kashanian +1 位作者 Huang-Teck Lee Frances Harding 《Quantitative Biology》 CAS CSCD 2024年第1期53-69,共17页
Protein biomarkers represent specific biological activities and processes, so they have had a critical role in cancer diagnosis and medical care for more than 50 years. With the recent improvement in proteomics techno... Protein biomarkers represent specific biological activities and processes, so they have had a critical role in cancer diagnosis and medical care for more than 50 years. With the recent improvement in proteomics technologies, thousands of protein biomarker candidates have been developed for diverse disease states. Studies have used different types of samples for proteomics diagnosis. Samples were pretreated with appropriate techniques to increase the selectivity and sensitivity of the downstream analysis and purified to remove the contaminants. The purified samples were analyzed by several principal proteomics techniques to identify the specific protein. In this study, recent improvements in protein biomarker discovery, verification, and validation are investigated. Furthermore, the advantages, and disadvantages of conventional techniques, are discussed. Studies have used mass spectroscopy (MS) as a critical technique in the identification and quantification of candidate biomarkers. Nevertheless, after protein biomarker discovery, verification and validation have been required to reduce the false-positive rate where there have been higher number of samples. Multiple reaction monitoring (MRM), parallel reaction monitoring (PRM), and selected reaction monitoring (SRM), in combination with stable isotope-labeled internal standards, have been examined as options for biomarker verification, and enzyme-linked immunosorbent assay (ELISA) for validation. 展开更多
关键词 biomarker discovery cancer biomarker gel-based methods gel-free methods mass spectroscopy PROTEOMICS
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Steering CO_(2)electrolysis selectivity by modulating the local reaction environment:An online DEMS approach for Cu electrodes 被引量:1
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作者 Ke Ye Guiru Zhang +6 位作者 Baoxin Ni Liang Guo Chengwei Deng Xiaodong Zhuang Changying Zhao Wen-Bin Cai Kun Jiang 《eScience》 2023年第4期89-98,共10页
Electrochemical CO_(2)reduction is a typical surface-mediated reaction,with its reaction kinetics and product distributions largely dependent on the dynamic evolution of reactive species at the cathode–catholyte inte... Electrochemical CO_(2)reduction is a typical surface-mediated reaction,with its reaction kinetics and product distributions largely dependent on the dynamic evolution of reactive species at the cathode–catholyte interface and on the resultant mass transport within the hydrodynamic boundary layer in the vicinity of the cathode.To resolve the complex local reaction environment of branching CO_(2)reduction pathways,we here present a dif-ferential electrochemical mass spectroscopic(DEMS)approach for Cu electrodes to investigate CO_(2)mass trans-port,the local concentration gradients of buffering anions,and the Cu surface topology effects on CO_(2)electrolysis selectivity at a temporal resolution of~400 ms.As a proof of concept,these tuning knobs were validated on an anion exchange membrane electrolyzer,which delivered a Faradaic efficiency of up to 40.4%and a partial current density of 121 mA cm^(-2)for CO_(2)-to-C_(2)H_(4)valorization.This methodology,which bridges the study of fundamental surface electrochemistry and the upgrading of practical electrolyzer performance,could be of general interest in helping to achieve a sustainable circular carbon economy. 展开更多
关键词 SPECTROELECTROCHEMISTRY CO_(2)reduction reaction Copper electrode Differential electrochemical mass spectroscopy Local reaction environment
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Phytochemical Estimation and Therapeutic Amelioration of Aesculus hippocastanum L. Seeds Ethanolic Extract in Gastric Ulcer in Rats Possibly by Inhibiting Prostaglandin Synthesis
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作者 Sahar Idris Anuradha Mishra Mohammad Khushtar 《Chinese Journal of Integrative Medicine》 SCIE CAS CSCD 2023年第9期818-824,共7页
Objective To quantify phytochemicals using liquid chromatography and mass spectroscopy(LCMS)analysis and explore the therapeutic effect of Aesculus hippocastanum L.(AH)seeds ethanolic extract against gastric ulcers in... Objective To quantify phytochemicals using liquid chromatography and mass spectroscopy(LCMS)analysis and explore the therapeutic effect of Aesculus hippocastanum L.(AH)seeds ethanolic extract against gastric ulcers in rats.Methods Preliminary phytochemical testing and LCMS analysis were performed according to standard methods.For treatment,the animals were divided into 7 groups including normal control,ulcer control,self-healing,AH seeds low and high doses,ranitidine and per se groups.Rats were orally administered with 10 mg/kg of indomethacin,excluding the normal control group(which received 1%carboxy methyl cellulose)and the per se group(received 200 mg/kg AH seeds extract).The test group rats were then given 2 doses of AH seeds extract(100 and 200 mg/kg,respectively),while the standard group was given ranitidine(50 mg/kg).On the 11th day,rats in all groups were sacrificed,and their stomach was isolated to calculate the ulcer index,and other parameters such as blood prostaglandin(PGE2),tissue superoxide dismutase(SOD),catalase(CAT),malonyldialdehyde(MDA),and glutathione(GSH).All isolated stomach tissues were analyzed for histopathological findings.Results The phytochemical examination shows that the AH seeds contain alkaloids,flavonoids,saponins,phenolic components,and glycosides.LCMS analysis confirms the presence of quercetin and rutin.The AH seeds extract showed significant improvement in gastric mucosa conditions after indomethacin-induced gastric lesions(P<0.01).Further marked improvement in blood PGE2 and antioxidant enzymes,SOD,CAT,MDA and GSH,were observed compared with self-healing and untreated ulcer-induced groups(P<0.01).Histopathology results confirmed that AH seeds extract improved the mucosal layer and gastric epithelial membrane in treated groups compared to untreated ulcer-induced groups.Conclusions LCMS report confirms the presence of quercetin and rutin in AH seeds ethanolic extract.The therapeutic effect of AH seeds extract against indomethacin-induced ulcer in rat model indicated the regenerated membrane integrity,with improved cellular functions and mucus thickness.Further,improved antioxidant enzyme level would help to reduce PGE2 biosynthesis. 展开更多
关键词 Aesculus hippocastanum L. pharmacological action PHYTOCHEMICAL physicochemical analysis liquid chromatography and mass spectroscopy analysis gastro-protective activity
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Biodegradation of Crystal Violet by Agrobacterium radiobacter 被引量:5
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作者 G.K.Parshetti S.G.Parshetti +3 位作者 A.A.Telke D.C.Kalyani R.A.Doong S.P.Govindwar 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2011年第8期1384-1393,共10页
Agrobacterium radiobacter MTCC 8161 completely decolorized the Crystal Violet with 8 hr (10 mg/L) at static anoxic conditions. The decreased decolorization capability by A. radiobacter was observed, when the Crystal... Agrobacterium radiobacter MTCC 8161 completely decolorized the Crystal Violet with 8 hr (10 mg/L) at static anoxic conditions. The decreased decolorization capability by A. radiobacter was observed, when the Crystal Violet concentration was increased from 10 to 100 mg/L. Semi-synthetic medium containing 1% yeast extract and 0.1% NH4C1 has shown 100% decolorization of Crystal Violet within 5 hr. A complete degradation of Crystal Violet by A. radiobacter was observed up to 7 cycles of repeated addition (10 rag/L). When the effect of increasing inoculum concentration on decolorization of Crystal Violet (100 mg/L) was studied, maximum decolorization was observed with 15% inoculum concentration. A significant increase in the activities of laccase (184%) and aminopyrine N-demethylase (300%) in cells obtained after decolorization indicated the involvement of these enzymes in decolorization process. The intermediates formed during the degradation of Crystal Violet were analyzed by gas chromatography and mass spectroscopy (GC/MS). It was detected the presence of N,N,N',N"-tetramethylpararosarfiline, IN, N-dimethylaminophenyl] [N-methylaminophenyl] benzophenone, N, N-dimethylaminobenzaldehyde, 4-methyl amino phenol and phenol. We proposed the hypothetical metabolic pathway of Crystal Violet biodegradation by A. radiobacter. Phytotoxicity and microbial toxicity study showed that Crystal Violet biodegradation metabolites were less toxic to bacteria (A. radiobacter, P. aurugenosa and A. vinelandii) contributing to soil fertility and for four kinds of plants (Sorghum bicolor, Vigna radiata, Lens culinaris and Triticum aestivum) which are most sensitive, fast growing and commonly used in Indian agriculture. 展开更多
关键词 Agrobacterium radiobacter Crystal Violet BIODEGRADATION gas chromatography and mass spectroscopy toxicity study
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Elucidating the electro-catalytic oxidation of hydrazine over carbon nanotube-based transition metal single atom catalysts 被引量:2
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作者 Jin Zhang Yaxin Wang +7 位作者 Chujie Yang Sian Chen Zhengjian Li Yi Cheng Haining Wang Yan Xiang Shanfu Lu Shuangyin Wang 《Nano Research》 SCIE EI CSCD 2021年第12期4650-4657,共8页
Elucidating the reaction mechanism of hydrazine oxidation reaction(HzOR)over carbon-based catalysts is highly propitious for the rational design of novel electrocatalysts for HzOR.In present work,isolated first-row tr... Elucidating the reaction mechanism of hydrazine oxidation reaction(HzOR)over carbon-based catalysts is highly propitious for the rational design of novel electrocatalysts for HzOR.In present work,isolated first-row transition metal atoms have been coordinated with N atoms on the graphite layers of carbon nanotubes via a M-N_(4)-C configuration(MSA/CNT,M=Fe,Co and Ni).The HzOR over the three single atom catalysts follows a predominant 4-electron reaction pathway to emit N_(2) and a negligible 1-electron pathway to emit trace of NH3,while their electrocatalytic activity for HzOR is dominated by the absorption energy of N2H4 on them.Furthermore,FeSA/CNT reverses the passivation effect on Fe/C and shows superior performance than CoSA/CNT and NiSA/CNT with a recorded high mass activity for HzOR due to the higher electronic charge of Fe over Co and Ni in the M-N_(4)-C configuration and the lowest absorption energy of N_(2)H_(4) on FeSA/CNT among the three MSA/CNT catalysts. 展开更多
关键词 hydrazine oxidation single atom catalyst transition metals differential electrochemical mass spectroscopy direct hydrazine fuel cell
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Evaluation of Bacillus sp. MZS10 for decolorizing Azure B dye and its decolorization mechanism 被引量:1
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作者 Huixing Li Ruijing Zhang +2 位作者 Lei Tang Jianhua Zhang Zhonggui Mao 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2014年第5期1125-1134,共10页
To evaluate decolorization and detoxification of Azure B dye by a newly isolated Bacillus sp. MZS 10 strain, the cultivation medium and decolorization mechanism of the isolate were investigated. The decolorization was... To evaluate decolorization and detoxification of Azure B dye by a newly isolated Bacillus sp. MZS 10 strain, the cultivation medium and decolorization mechanism of the isolate were investigated. The decolorization was discovered to be dependent on cell density of the isolate and reached 93.55% (0.04 g/L) after 14 hr of cultivation in a 5 L stirred-tank fermenter at 2.0 g/L yeast extract and 6.0 g/L soluble starch and a small amount of mineral salts. The decolorization metabolites were identified with ultra performance liquid chromatography-tandem mass spectroscopy (UPLC-MS). A mechanism for decolorization of Azure B was proposed as follows: the C=N in Azure B was initially reduced to -NH by nicotinamide adenine dinucleotide phosphate (NADPH)-dependent quinone dehydrogenase, and then the -NH further combined with -OH derived from glucose to form a stable and colorless compound through a dehydration reaction. The phytotoxicity was evaluated for both Azure B and its related derivatives produced by Bacillus sp. MZS 10 decolorization, indicating that the decolorization metabolites were less toxic than original dye. The decolorization efficiency and mechanism shown by Bacillus sp. MZS10 provided insight on its potential application for the bioremediation of the dye Azure B. 展开更多
关键词 Azure B Bacillus sp. DECOLORIZATION ultra performance liquid chromato graphy-tandem mass spectroscopy PHYTOTOXICITY
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Effect of Hydrogen on Corrosion and Stress Corrosion Cracking of AZ91 Alloy in Aqueous Solutions 被引量:1
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作者 Jian Chen Jian-Qiu Wang +2 位作者 En-Hou Han Wei Ke D.W.Shoesmith 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 2016年第1期1-7,共7页
The effect of hydrogen on the corrosion and stress corrosion cracking of the magnesium AZ91 alloy has been investigated in aqueous solutions. Hydrogen produced by corrosion in water diffuses into, and reacts with the ... The effect of hydrogen on the corrosion and stress corrosion cracking of the magnesium AZ91 alloy has been investigated in aqueous solutions. Hydrogen produced by corrosion in water diffuses into, and reacts with the Mg matrix to form hydride. Some of the hydrogen accumulates at hydride/Mg matrix (or secondary phase) interfaces as a consequence of slow hydride formation and the incompatibility of the hydride with the Mg matrix (or secondary phase), and combines to form molecular hydrogen. This leads to the development of a local pressure at the hydride/Mg matrix (or secondary phase) interface. The expansion stress caused by hydride formation and the local hydrogen pressure due to its accumulation result in brittle fracture of hydride. These two combined effects promote both the corrosion rate of the AZ91 alloy, and crack initiation and propagation even in the absence of an external load. Hydrogen absorption leads to a dramatic deterioration in the mechanical properties of the AZ91 alloy, indicating that hydrogen embrittlement is responsible for transgulanar stress corrosion cracking in aqueous solutions. 展开更多
关键词 AZ91 alloy CORROSION HYDROGEN Secondary ion mass spectroscopy (SIMS) Transgulanarstress corrosion cracking (TGSCC)
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