Search results for "Sorption"

showing 10 items of 4623 documents

Selective Laser Sintering of Metal-Organic Frameworks: Production of Highly Porous Filters by 3D Printing onto a Polymeric Matrix.

2019

Metal‐organic frameworks (MOFs) have raised a lot of interest, especially as adsorbing materials, because of their unique and well‐defined pore structures. One of the main challenges in the utilization of MOFs is their crystalline and powdery nature, which makes their use inconvenient in practice. Three‐dimensional printing has been suggested as a potential solution to overcome this problem. We used selective laser sintering (SLS) to print highly porous flow‐through filters containing the MOF copper(II) benzene‐1,3,5‐tricarboxylate (HKUST‐1). These filters were printed simply by mixing HKUST‐1 with an easily printable nylon‐12 polymer matrix. By using the SLS, powdery particles were fused t…

porosityMaterials sciencematerials sciencelaser sinteringMixing (process engineering)3D printingNanotechnologyorganometalliyhdisteet010402 general chemistry01 natural scienceslaw.inventionMatrix (chemical analysis)huokoisuusAdsorptionlaw3D-tulostuspolymeeritmateriaalitiedePorosityta116metal-organic frameworkspolymerschemistry.chemical_classification010405 organic chemistrybusiness.industryGeneral ChemistryPolymer0104 chemical sciencesSelective laser sinteringchemistryadsorptionMetal-organic frameworkadsorptiobusinessChemPlusChem
researchProduct

Inside Cover: Hydrogen-Bonded Open-Framework with Pyridyl-Decorated Channels: Straightforward Preparation and Insight into Its Affinity for Acidic Mo…

2017

International audience; A hydrogen-bonded open framework with pores decorated by pyridyl groups was constructed by off-charge-stoichiometry assembly of protonated tetrakis(4-pyridyloxymethyl)methane and [Al(oxalate)(3)](3-), which are the H-bond donor and acceptor of ionic H-bond interactions, respectively. This supramolecular porous architecture (SPA-2) has 1nm-large pores interconnected in 3D with large solvent-accessible void (53%). It demonstrated remarkable affinity for acidic organic molecules in solution, which was investigated by means of various carboxylic acids including larger drug molecules. Competing sorption between acetic acid and its halogenated homologues evidenced good sel…

porosityabsolute-structureHydrogenSupramolecular chemistrychemistry.chemical_element010402 general chemistry01 natural sciences[ CHIM ] Chemical SciencesCatalysissupramolecular chemistrycrystalhost-guest systemsPolymer chemistryMoleculesolid-state nmr[CHIM]Chemical Scienceshost frameworkssorption010405 organic chemistryHydrogen bondmicroporous materialsOrganic ChemistryarchitecturesSorptionGeneral Chemistrymetal-organic frameworkenantioselective separationOpen frameworkcations0104 chemical scienceschemistryadsorptionhydrogen bondsCover (algebra)
researchProduct

Sponge‐Like Behaviour in Isoreticular Cu(Gly‐His‐X) Peptide‐Based Porous Materials

2015

We report two isoreticular 3D peptide-based porous frameworks formed by coordination of the tripeptides Gly-L-His-Gly and Gly-L-His-L-Lys to Cu(II) which display sponge-like behaviour. These porous materials undergo structural collapse upon evacuation that can be reversed by exposure to water vapour, which permits recovery of the original open channel structure. This is further confirmed by sorption studies that reveal that both solids exhibit selective sorption of H2 O while CO2 adsorption does not result in recovery of the original structures. We also show how the pendant aliphatic amine chains, present in the framework from the introduction of the lysine amino acid in the peptidic backbo…

postsynthetic modificationsPeptideTripeptideCatalysismetal–organic frameworksAdsorptionMetalloproteinsPolymer chemistryUreaMoleculePorositywater adsorptionchemistry.chemical_classificationMolecular Structurenanoporous materialsOrganic ChemistrySorptionGeneral ChemistryFull PaperschemistryChemical engineeringpeptidesMetal-organic frameworkAdsorptionPorous mediumOligopeptidesPorosityCopperChemistry – A European Journal
researchProduct

Absorption of European Funds by Romania During 2014-2020

2021

Abstract The time span between 2014 and 2020 constitutes a new, multi-annual financial framework. During this time, by negotiating with the European Union, Romania received financing through 5 major types of funds which were part of the European Structural Investments Funds (ESIF) and which were structured in six major Operational Programs, the most consistent of which is POIM - The Major Infrastructure Operational Program (MIOP). Within this financial framework, Romania needs to improve its absorption of funds based on the experience gained in the previous framework, with regards to issues like bureaucracy, corruption, lack of qualified personnel for the implementation of projects, the tra…

programming periodHF5001-6182Social Psychologyeuropean projectsEconomics Econometrics and Finance (miscellaneous)Analytical chemistryBusiness Management and Accounting (miscellaneous)multiannual financial frameworkBusinessBusinessAbsorption (electromagnetic radiation)absorption rateoperational programsStudies in Business and Economics
researchProduct

Total oxidation of propene at low temperature over Co3O4–CeO2 mixed oxides: Role of surface oxygen vacancies and bulk oxygen mobility in the catalyti…

2008

Liotta, L. F. Ousmane, M. Di Carlo, G. Pantaleo, G. Deganello, G. Marci, G. Retailleau, L. Giroir-Fendler, A.; Co3O4, CeO2 and Co3O4-CeO2 mixed oxides with Co/Ce nominal atomic ratio 0.1:5, prepared by co-precipitation method with sodium carbonate, were tested in the oxidation of propene under lean condition and the catalyst stability was checked by performing three consecutive heating-cooling cycles. Characterization of the textural properties were performed by surface area measurement BET, X-ray diffraction (XRD) and scanning electron microscopy (SEM) measurements. Among the Co3O4-CeO2 mixed oxides, Co3O4 (30 Wt%)-CeO2 (70 wt%) gives the best activity attaining full propene conversion at …

propene oxidation Co3O4 CeO2Process Chemistry and TechnologyInorganic chemistrychemistry.chemical_elementBinary compound[CHIM.CATA]Chemical Sciences/Catalysis02 engineering and technology010402 general chemistry021001 nanoscience & nanotechnologyHeterogeneous catalysis01 natural sciencesOxygenCatalysis0104 chemical sciencesCatalysisPropenechemistry.chemical_compoundchemistryDesorptionAtomic ratio0210 nano-technologySodium carbonateApplied Catalysis A: General
researchProduct

Molecular spectra of liquors as method of studying delignification process

2011

FTIR-spectra of dried compounds of black liquors after aspen kraft cooks of different duration were obtained. Twelve samples corresponding to changing H-factor value in limits 4-1010 were investigated. The parameters of selected bands corresponding to lignin fragments vibrations were calculated using mathematical treatment methods. It was revealed that the positions and bandwidths of these lignin bands did not change. During cook at the first stage (H-factor values 4-200) their intensities strongly increased with different rates. During the next time period when the H-factor values were more than 200 a slow phase with small changes of the bands intensities were revealed. The IR-spectra of b…

pulpaspen woodIR absorption
researchProduct

Combined Spectroscopic and TD-DFT Analysis to Elucidate Substituent and Acidochromic Effects in Organic Dyes: A Case Study on Amino- versus Nitro-Sub…

2020

Made available in DSpace on 2020-12-12T01:33:30Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-01-01 A combined spectroscopic and TD-DFT case study was performed, to identify a robust method to calculate the complex near UV/Vis absorption spectra of various amino- vs. nitro-substituted 2,4-diphenylquinolines, which vary strongly under neutral and successively acidic conditions. For this, different DFT functionals were tested for geometry optimization and the TD part to calculate the neutral and different protonated species in a fast screening approach, i. e. using single point calculations in an implicit solvent. Offset-corrected M06HF, hitherto only applied to polymers, was identif…

quinolinesAbsorption spectroscopyabsorption spectradual emissionSubstituentProtonation02 engineering and technology010402 general chemistry021001 nanoscience & nanotechnologyEnergy minimization01 natural sciencesFluorescenceAtomic and Molecular Physics and Optics0104 chemical sciencesSolventchemistry.chemical_compoundchemistryComputational chemistryacidochromismNitroDensity functional theoryfluorescencePhysical and Theoretical Chemistry0210 nano-technologydensity functional theory
researchProduct

Sorption and mechanism studies of Cu2+, Sr2+ and Pb2+ ions on mesoporous aluminosilicates/zeolite composite sorbents

2020

The research aimed to develop a novel mesoporous aluminosilicate/zeolite composite by the template co-precipitation method. The effect of aluminosilicate (AlSi) and zeolite (NaY) on the basic properties and adsorption capacity of the resultant composite was conducted at different mass ratios of AlSi/NaY (i.e., 5/90, 10/80, 15/85, 20/80, and 50/50). The adsorption characteristics of such composite and its feedstock materials (i.e., aluminosilicates and zeolite) towards radioactive Sr2+ ions and toxic metals (Cu2+ and Pb2+ ions) in aqueous solutions was investigated. Results indicated that BET surface area (SBET), total pore volume (VTotal), and mesopore volume (VMeso) of prepared materials f…

radioactive ionraskasmetallitzeoliititmesoporous aluminosilicatesilikaatitadsorptiontextural propoertyheavy metalzeolitevedenkäsittelyadsorptiokomposiitit
researchProduct

Strongly Coupled Coherent Phonons in Single-Layer MoS 2

2019

We present a transient absorption setup combining broadband detection over the visible-UV range with high temporal resolution ($\sim$20fs) which is ideally suited to trigger and detect vibrational coherences in different classes of materials. We generate and detect coherent phonons (CPs) in single layer (1L) MoS$_2$, as a representative semiconducting 1L-transition metal dichalcogenide (TMD), where the confined dynamical interaction between excitons and phonons is unexplored. The coherent oscillatory motion of the out-of-plane $A'_{1}$ phonons, triggered by the ultrashort laser pulses, dynamically modulates the excitonic resonances on a timescale of few tens fs. We observe an enhancement by…

ramanspectroscopyPhononExcitonGeneral Physics and AstronomyFOS: Physical sciences02 engineering and technologyApplied Physics (physics.app-ph)thz phonons010402 general chemistry01 natural sciencesMolecular physicssymbols.namesakephotoinduced bandgap renormalizationtransient absorption spectroscopyUltrafast laser spectroscopyMesoscale and Nanoscale Physics (cond-mat.mes-hall)General Materials Sciencepulsesexciton−phonon interactionPhysicsab initio calculationCondensed Matter - Materials ScienceCondensed Matter - Mesoscale and Nanoscale Physicstransition metal dichalcogenidesgrapheneGeneral Engineeringmonolayer mos2ResonanceMaterials Science (cond-mat.mtrl-sci)excitationmonodynamicsPhysics - Applied Physics021001 nanoscience & nanotechnology0104 chemical sciencesAmplitudeOrders of magnitude (time)coherent phononsexciton-phonon interactionsymbols0210 nano-technologyRaman spectroscopyExcitationACS Nano
researchProduct

KOSMOS 2017 Peru Side Experiment: nutrients, phytoplankton abundances, enzyme rates, photophysiology

2022

This data was collected during an short-term incubation experiment in March 2017 that investigated the response of a surface plankton community to upwelling. This experiment was carried in the framework of the SFB754-funded KOSMOS mesocosm study that took place in La Punta, Callao, Peru between February-April 2017. A total of six different treatments were used to disentangle chemical and biological characteristics of deep water that influence surface plankton blooms: 2 different deep water sources with different nutrient concentrations; 3 treatments to distinguish the effects of inorganic nutrients, organic nutrients and deep water microbial populations. Measured variables include inorganic…

ratioDay of experimentSFB754colored dissolved organic matter at 325 nmNitriteChlorophyll aAbsorption coefficient colored dissolved organic matter at 254 nmClimate - Biogeochemistry Interactions in the Tropical Ocean (SFB754)colorimetric determinationFluorometerFluorometricNitrateNanoplanktonPhytoplankton cells phycocyanin-containing (FL-4)PicoeukaryotesFluorometer fast repetition rateCalculatedFlow cytometryNutrient consumption ratioforward scatterSynechococcusupwelling systemsMesocosm experimentSpectrophotometricClimate Biogeochemistry Interactions in the Tropical Ocean SFB754SilicateBiogeochemistryBiospheric SciencesMaximum photochemical quantum yield of photosystem IIenzyme activitycell sizeDissolved inorganic nitrogen/dissolved inorganic phosphorus ratioKOSMOS_2017chainsAbsorption coefficient colored dissolved organic matter 250 nm/365 nm ratioeastern tropical South Pacific OceanKOSMOSExcess phosphateAbsorption coefficient colored dissolved organic matter at 325 nmNatural SciencesGeosciencescolored dissolved organic matter at 254 nmphycocyanin containing FL 4Absorption coefficientPhosphateTank numberPhytoplankton cells chainsNetwork of Leading European AQUAtic MesoCOSM Facilities Connecting Mountains to Oceans from the ArctReplicatenutrientsfast repetition rateDATE TIMECryptophytesMicrophytoplanktonPhytoplankton cellsLeucine aminopeptidase activityDissolved inorganic nitrogen dissolved inorganic phosphorus ratiofungiEnzymatic assayContinuous flow analyserTreatmentDATE/TIMEcolored dissolved organic matter 250 nm 365 nmPhytoplanktonPhytoplankton cell size forward scatterNetwork of Leading European AQUAtic MesoCOSM Facilities Connecting Mountains to Oceans from the Arctic to the Mediterranean (AQUACOSM)CDOMContinuous flow analyser colorimetric determinationNitrate and Nitrite
researchProduct