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Water-to-air transfer of branched and linear PFOA:Influence of ph,concentration and water type

Emerging Contaminants 2017年第1期3卷 46-53页

作者： jana h.johansson hong Yan Urs Berger Ian T.Cousins Department of Environmental Science and Analytical Chemistry(ACES) Stockholm UniversitySvante Arrhenius v€ag 811418 StockholmSweden State Key Laboratory of Pollution Control and Resources Reuse College of Environmental Science and EngineeringTongji UniversityShanghaiChina Department Analytical Chemistry Helmholtz Centre for Environmental Research e UFZLeipzigGermany

The volatilisation of perfluorooctanoic acid(PFOA)was measured experimentally at a range of ph values using a previously published laboratory ***-to-air transfer was studied for five structural isomers,namely:the linear isomer(n-PFOA)and the four most commonly occurring branched isomers(3-,4-,5-and 6-PFOA).The influence of water concentration and water type on the ph-dependent waterto-air transfer was also investigated for *** water-to-air transfer was studied over the course of 48 h at ph values ranging from 0.2 to *** all experimental conditions tested,the volatilisation of PFOA was negligible at ph>*** experiments performed with MilliQ water,volatilisation increased with decreasing water *** experiments performed with tap water and lake water,maximum volatilisation was observed at ph *** concentration of PFOA in water had no influence on the ph value at which water-to-air transfer was observed(*** phhe concentration range tested(0.1e50 mg/L PFOA in deionised water).Although the percentage of PFOA volatilised was significantly different for the four branched isomers at low ph,volatilisation was not observed above ph 2.5 for any branched isomer suggesting that all PFOA isomers have a low ***,these laboratory results demonstrate that volatilisation of any structural isomer of PFOA from water is negligible at environmentally-relevant *** is unlikely that PFOA isomers will be fractionated in the environment as a result of volatilisation because it is a process of negligible environmental relevance.

关键词： PFOA Isomer Branched Acid dissociation pKa

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Fabrication and evaluation of carboxymethyl guar gum-chitosan interpenetrating polymer network (IPN) nanoparticles for controlled drug delivery

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Medicine in Novel Technology and Devices 2024年第2期22卷 73-79页

作者： Chandrani Roy Arijit Gandhi Sreejan Manna Sougata jana Department of Pharmaceutics Gupta College of Technological SciencesAshram MoreG.T.RoadAsansol713301West BengalIndia Department of Pharmaceutical Technology Brainware UniversityBarasatKolkataWest Bengal700125India Department of health and Family Welfare Directorate of Health ServicesKolkataIndia

Guar gum(GG)has drawn more interest from researchers in the last several decades for the controlled delivery of *** aim of the research is to fabricate and evaluate an interpenetrating polymer network(IPN)based nanocarriers system employing chemically modified GG to achieve controlled release of *** present study,we have reported the synthesis of carboxymethyl GG-chitosan IPN nanoparticles for controlled release of metformin *** guar gum(CMGG)was synthesized and employed for developing IPN nanoparticles in combination with chitosan in varying polymeric ratios.A cross-linking agent,sodium tripolyphosphate(Na-TPP)was used for the synthesis of IPN colloidal suspension of nanoparticles which was lyophilized to obtain *** carboxymethylation of GG was confirmed through Fourier transform infra-red spec*** mean particle size was 440.6 nm indicating a polydispersity index of *** drug entrapment efficiency was found to vary between 67.461.64%to 88.232.02%.The differential scanning calorimetry study revealed the presence of amorphous metformin hydrochloride as a homogenous dispersion in nanoparticles(NPs)*** vitro drug release study indicated controlled release ability of developed IPN matrix.A2 formulation(chitosan:CMGG-1:1)exhibited 78.110.27%release after 8 *** evaluation performed in alloxan-treated diabetic rat model exhibited a prolonged hypoglycemic efficacy over 6 h,for A2 formulation treated group,compared to the group receiving only metformin hCl,which demonstrated a reduction in blood glucose levels for up to 4 *** study findings demonstrated the efficacy of the CMGG-chitosan based IPN nanoparticulate system for sustained delivery of therapeutic agents.

关键词： Carboxymethyl guar gum Chitosan Interpenetrating polymer network Nanoparticles Controlled release Metformin hydrochloride

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Effect of mechanical activation on thiosulfate leaching of gold from complex sulfide concentrate

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Transactions of Nonferrous Metals Society of China 2011年第12期21卷 2744-2751页

作者： Mohsen hAShEMZADEhFINI jana FICERIOVá Emad ABKhOShK Behrouz Karimi ShAhRAKI Iran Mineral Processing Research Center Karaj Iran Institute of Geotechnics of Slovak Academy of Sciences Watsonova 4504353 Koice Slovakia Department of Mining Engineering Science and Research Branch Islamic Azad University Tehran Iran

The use of mechanical activation to enhance gold recovery from a CuPbZn complex sulfide concentrate was investigated. The effects of milling time, ball size, sample to ball ratio and milling speed on thiosulfate leaching were studied. Under optimum conditions of milling time 1 h, ball size 20 mm, sample to ball ratio 1/15 and mill speed 600 r/min, nearly 78% of sample is amorphized, particle size decreases from d100=30 μm to d100=8 μm, specific surface area increases from 1.3 m2/g to 4.6 m2/g and gold recovery enhances from 17.4 % in non-activated sample to 73.26 %.

关键词： mechanical activation thiosulfate leaching refractory ore extraction of gold

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Investigating the coagulation of non-proteinaceous algal organic matter: Optimizing coagulation performance and identification of removal mechanisms

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Journal of Environmental Sciences 2019年第5期31卷 25-34页

作者： jana Naceradska Katerina Novotna Lenka Cermakova Tomas Cajthaml Martin Pivokonsky Institute of hydrodynamics of the Czech Academy of Sciences Institute of Microbiology of the Czech Academy of Sciences

The removal of algal organic matter(AOM) is a growing concern for the water treatment industry worldwide. The current study investigates coagulation of non-proteinaceous AOM(AOM after protein separation), which has been minimally explored compared with proteinaceous fractions. Jar tests with either aluminum sulphate(alum) or polyaluminium chloride(PACl) were performed at doses of 0.2–3.0 mg Al per 1 mg of dissolved organic carbon in the p h range 3.0–10.5. Additionally, non-proteinaceous matter was characterized in terms of charge, molecular weight and carbohydrate content to assess the treatability of its different fractions. Results showed that only up to 25% of non-proteinaceous AOM can be removed by coagulation under optimized conditions. The optimal coagulation p h(6.6–8.0 for alum and 7.5–9.0 for PACl) and low surface charge of the removed fraction indicated that the prevailing coagulation mechanism was adsorption of non-proteinaceous matter onto aluminum hydroxide precipitates. The lowest residual Al concentrations were achieved in very narrow p h ranges, especially in the case of PACl. high-molecular weight saccharidelike organics were amenable to coagulation compared to low-molecular weight(heir high content in non-proteinaceous matter(about 67%) was the reason for its low removal. Comparison with our previous studies implies that proteinaceous and nonproteinaceous matter is coagulated under different conditions due to the employment of diverse coagulation mechanisms. The study suggests that further research should focus on the removal of low-molecular weight AOM, reluctant to coagulate, with other treatment processes to minimize its detrimental effect on water safety.

关键词： Algal organic matter Chlorella vulgaris Coagulation Flocculation Non-proteinaceous matter Water treatment

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Electron transfer dynamics in Schottky junction photocatalyst during electron donor-assisted hydrogen production

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Journal of Materials Science & Technology 2023年第28期159卷 1-9页

作者： Jianjun Zhang Jingjing Liu Zheng Meng Sanjib jana Linxi Wang Bicheng Zhu Laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of Geosciences68 Jincheng StreetWuhan 430078China School of Chemistry Chemical Engineering and BiotechnologyNanyang Technological University21 Nanyang LinkSingapore 637371Singapore Jiangxi Key Laboratory of Surface Engineering Jiangxi Science and Technology Normal UniversityNanchang 330038China

Electron donors(EDs)are widely used to improve the h 2 production performance of Schottky junction photocatalysts,but the functions of EDs are still unknown from the perspective of electron transfer ***,Pt nanocluster-decorated CdS nanorod is successfully prepared to construct a typical CdS/Pt Schottky *** nanoclusters with a diameter of∼2 nm are deposited on the surface of CdS nanorods by in situ photoreduction at sub-zero *** CdS/Pt photocatalyst using lactic acid shows a higher h_(2)production rate of 4762μmol g^(-1)h^(-1)compared to that using methanol,tri-ethanolamine,and *** understand the cause,the dynamics of photogenerated carriers in CdS/Pt photocatalysts during ED-assisted h_(2)production are revealed by femtosecond transient absorption *** the four organic EDs,lactic acid enables the fastest electron transfer rate of 1.8×10^(9)s^(-1)and the highest electron transfer efficiency of 76%at the CdS/Pt interface due to the most efficient hole *** work sheds light on the importance of efficient interfacial electron transfer for im-proving the photocatalytic performance of Schottky junction photocatalysts.

关键词： Transient absorption spectroscopy Interfacial electron transfer Electron transfer rate Electron transfer efficiency hole consumption

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Active stabilization of terahertz waveforms radiated from a two-color air plasma

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Photonics Research 2022年第1期10卷 96-103页

作者： YONGhAO MI KYLE JOhNSTON VALENTINA ShUMAKOVA SφREN h.MφLLER KAMALESh jana ChUNMEI ZhANG ANDRé STAUDTE ShAWN SEDERBERG PAUL B.CORKUM Joint Attosecond Science Laboratory University of Ottawa and National Research Council CanadaOntario K1N 6X1Canada School of Engineering Science Simon Fraser UniversityBurnabyBritish Columbia V5A 1S6Canada

Intense laser fields focused into ambient air can be used to generate high-bandwidth current densities in the form of plasma channels and *** with bichromatic fields enables us to adjust the amplitude and sign of these currents using the relative phase between the two light ***-color filamentation in gas targets provides a route to scaling the energy of terahertz pulses to microjoule levels by driving the plasma channel with a high-energy laser ***,the structure of plasma channels is highly susceptible to drifts in both the relative phase and other laser parameters,making control over the waveform of the radiated terahertz fields *** establish a clear link between the phase dependence of plasma currents and terahertz radiation by comparing in situ detection of current densities and far-field detection of terahertz electric *** show that the current measurement can be used as a feedback parameter for stabilizing the terahertz *** approach provides a route to energetic terahertz pulses with exceptional waveform stability.

关键词： stabilization terahertz Active

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hydrodesulfurization activities of NiMo catalysts supported on mechanochemically prepared Al-Ce mixed oxides

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Chinese Journal of Catalysis 2016年第2期37卷 258-267页

作者： Květa Jirátová Alla Spojakina Luděk Kaluza Radostina Palcheva jana Balabánová Georgi Tyuliev 捷克共和国科学院化工过程基础研究所捷克共和国布拉格保加利亚科学院催化研究所保加利亚索非亚

Al2O3-CeO2 supports containing 1-10 wt%Ce were prepared mechanochemically by milling aluminum and/or cerium nitrates with ***,（Nh4）4NiMo6O（24）,was used as the precursor of the Ni and Mo to prepare NiMo6/Al2O3-CeO2 components in catalysts by impregnation *** physicochemical properties of the catalysts were determined using chemical analysis,X-ray diffraction,temperature-programmed h2 reduction,temperature-programmed Nh3 desorption,X-ray photoelectron spectroscopy（XPS）,and the Brunauer-Emmett-Teller *** catalyst acidity decreased with increasing Ce concentration in the *** showed that the NiS/MoS ratio decreased two-fold for the Ce-modified alumina ***6/Al2O3,which had the highest acidity,showed the highest activity in hydrodesulfurization of 1-benzothiophene（normalized per weight of catalyst）.The concentration of surface MoOxSy species（which is equal to the concentration of Mo^（5＋）） gradually decreased to zero for catalysts with Ce concentrations 10 wt%.however,the activities of all the catalysts prepared mechanochemically from Al2O3 and Al2O3-CeO2supports significantly exceeded that of a reference NiMo6/Al2O3 catalyst prepared by impregnation method using the same precursor and with the same composition.

关键词： Nickel Molybdenum Alumina Ceria Anderson heteropolymolybdate 1-Benzothiophene hydrodesulfurization Mechanochemical method

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Observation of Resistive Switching Memory by Reducing Device Size in a New Cr/CrO_x/TiO_x/TiN Structure

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Nano-Micro Letters 2015年第4期7卷 392-399页

作者： Debanjan jana Subhranu Samanta Sourav Roy Yu Feng Lin Siddheswar Maikap Thin Film Nano Tech. Lab. Department of Electronic Engineering Chang Gung University

The resistive switching memory characteristics of 100 randomly measured devices were observed by reducing device size in a Cr/Cr Ox/Ti Ox/Ti N structure for the first *** electron microscope image confirmed a viahole size of 0.4 lm.A 3-nm-thick amorphous Ti Oxwith 4-nm-thick polycrystalline Cr Oxlayer was observed.A small 0.4-lm device shows reversible resistive switching at a current compliance of 300 l A as compared to other larger size devices(1–8 lm)owing to reduction of leakage current through the Ti *** device-to-device uniformity with a yield of[85%has been clarified by weibull distribution owing to higher slope/shape *** switching mechanism is based on oxygen vacancy migration from the Cr Oxlayer and filament formation/rupture in the Ti *** read pulse endurance of[105cycles,good data retention of 6 h,and a program/erase speed of 1 ls pulse width have been obtained.

关键词： CrOx TiOx Resistive switching memory Slope/shape factor Device size

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To eat or get heat： Behavioral trade-offs between thermoregulation and feeding in gregarious necrophagous larvae

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Insect Science 2018年第5期25卷 883-893页

作者： jana Podhorna Cindy Aubernon Marie Borkovcova Julien Boulay Valery hedouin Damien Charabidze Department of Zoology Fisheries Hydrobiology and Apiculture Mendel University in Brno Czech Repubfic Unite de Taphonomie Medico-Legale University of Lille CHU Lille EA France

The thermoregulation behavior ofLucilia sericata larvae （Diptera： Calliphori- dae）, a necrophagous species that feeds on vertebrate cadavers, was investigated. These larvae require high heat incomes to develop, and can elevate temperatures by forming large aggregates. We hypothesized that L. sericata larvae should continue to feed at temperatures up to 38 ℃, which can be reached inside larval masses. Thermal regulation behavior such as movement between a hot food spot and colder areas was also postulated. The hypotheses were tested by tracking for 1 h the activity of single, starved third instar larvae in a Petri dish containing 1 food spot （FS） that was heated to a constant temperature of 25 ℃, 34 ℃ or 38 ℃ with an ambient temperature of 25 ℃. The influence of previous conspecific activity in the food on larval behavior was also tested. The crops of larvae were dissected to monitor food content in the digestive systems. Based on relative crop measurements, larvae fed at all food temperatures, but temperature strongly affected larval behavior and kinematics. The total time spent by larvae in FS and the duration of each stay decreased at high FS temperature. Previous activity of conspecifics in the food slightly increased the time spent by larvae in FS and also decreased the average distance to FS. Therefore, necrophagous L. sericata larvae likely thermoregulate during normal feeding activities by adjusting to local fluctuations in temperature, particularly inside maggot masses. By maintaining a steady internal body temperature, larvae likely reduce their development time.

关键词： blowflies Calliphoridae forensic entomology foraging thermoregulation video tracking

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Solid and liquid state characterization of tetrahydrocurcumin using XRPD, FT-IR, DSC, TGA, LC-MS, GC-MS, and NMR and its biological activities

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Journal of Pharmaceutical Analysis 2020年第4期10卷 334-345页

作者： Mahendra Kumar Trivedi Parthasarathi Panda Kalyan Kumar Sethi Mayank Gangwar Sambhu Charan Mondal Snehasis jana Trivedi Global Inc. Henderson89052NevadaUSA Trivedi Science Research Laboratory Pvt.Ltd. Thane(W)-400604MaharashtraIndia

Tetrahydrocurcumin(ThC)is one of the major metabolites of curcumin(CUR),an ancient bioactive natural polyphenolic *** research article describes both the solid and liquid state characterization of ThC using advanced spectroscopic and thermo-analytical ***-inflammatory,anti-oxidant,and neuroprotective activities of ThC were investigated using in vitro cell *** chromatography-mass spectrometry analysis revealed that our sample comprised 95.15%ThC,0.51%tetrahydrodemethoxycurcumin(ThDC),3.40%hexahydrocurcumin,and 0.94%*** chromatography-mass spectrometry analysis indicated the presence of 96.68%ThC and 3.32%*** in solution existed as keto-enol tautomers in three different forms at different retention time,but the enol form was found to be dominant,which was also supported by nuclear magnetic resonance *** was thermally stable up to 335.55*** exhibited more suppression of cytokines(TNF-a,IL-1b,and MIP-1a)than CUR in a concentration-dependent manner in mouse splenocytes,while NK-cell and phagocytosis activity was increased in *** showed a significant reduction of free radicals(LPO)along with improved antioxidant enzymes(SOD and catalase)and increased free radical scavenging activity against ABTSt radicals in hepG2 *** displayed higher protection capability than CUR from oxidative stress and neuronal damage by improving cell viability against h2O2 induced hepG2 cells and MPPt induced Sh-SY5Y cells,respectively,in a concentration-dependent ***,a variation of the biological activities of ThC might rely on its keto-enol form and the presence of other ThC analogs as *** present study could be advantageous for further research on ThC for better understanding its physicochemical properties and biological variation.

关键词： Tetrahydrocurcumin Liquid chromatography-mass spectrometry Spectroscopic and thermal analysis Keto-enol tautomer Anti-inflammatory Antioxidant

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