Factors affecting quantitative determinations by x-ray photoelectron spectroscopy

An investigation was made into the effects of tannery sludge on soil chemical properties and microbial communities in a typical soil profile with long-term tannery sludge contamination, North China. The results showed that trivalent chromium (Cr(III)), ammonium, organic nitrogen, salinity and sulfide were the predominant contaminants in tannery sludge. Although the tannery sludge contained high chromium (Cr, 3,0970 mg/kg), the proportion of mobile Cr forms (exchangeable plus carbonate-bound fraction) only accounted for 1.32%. The X-ray diffraction and X-ray photoelectron spectroscopy results further demonstrated that the Cr existed in a stable state of oxides and iron oxides. The alkaline loam soil had a significant retardation effect on the migration of salinity, ammonium, Cr(III) and sulfide, and the accumulation of these contaminants occurred in soils (0–40 cm). A good correlation (R2 = 0.959) was observed between total organic carbon (TOC) and Cr(III) in the soil profile, indicating that the dissolved organic matter from sludge leachate promoted the vertical mobility of Cr(III) via forming Cr(III)-organic complexes. The halotolerant bacteria (Halomonas and Tepidimicrobium) and organic degrading bacteria (Flavobacteriaceae, Tepidimicrobium and Balneola) became the dominant microflora in the soil profile. High contents of salinity, Cr and nitrogen were the main environmental factors affecting the abundance of indigenous microorganisms in soils.

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Factors influencing timber gluability with one-part polyurethanes – studied with nine Australian timber species

Holzforschung ◽

10.1515/hf.2006.066 ◽

2006 ◽

Vol 60 (4) ◽

pp. 423-428 ◽

Cited By ~ 4

Author(s):

Petri Widsten ◽

Voytek S. Gutowski ◽

Sheng Li ◽

Tony Cerra ◽

Sharon Molenaar ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Sessile Drop ◽

Lap Joints ◽

Sessile Drop Method ◽

Timber Species ◽

Adhesion Properties ◽

Factors Affecting ◽

X Ray ◽

Polyurethane Adhesives ◽

Creep Loading

Abstract The bulk and surface properties of blocks of nine Australian wood species of commercial importance were investigated to elucidate the factors affecting timber gluability with structural one-component polyurethane adhesives. Cross-lap joints were prepared from freshly sanded blocks and the joints were subjected to creep loading in a condensing humidity environment. The median tensile strength (MTS) of the joints was found to improve with decreasing phenolic extractives content, lower timber density and decreasing lipophilic surface extractives content. The latter was assessed from O/C atomic ratios of the timber surfaces determined by X-ray photoelectron spectroscopy (XPS). The content of bulk lipophilic extractives and lignins and wettability of the surface as determined by the sessile drop method did not reveal significant correlations with the adhesion properties. The adhesion tests indicated significant gluability differences between the species investigated.

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Adsorption of Pb(II) from Aqueous Solution by Mussel Shell-Based Adsorbent: Preparation, Characterization, and Adsorption Performance

Materials ◽

10.3390/ma14040741 ◽

2021 ◽

Vol 14 (4) ◽

pp. 741

Author(s):

Quan Wang ◽

Fangyuan Jiang ◽

Xiao-Kun Ouyang ◽

Li-Ye Yang ◽

Yangguang Wang

Keyword(s):

Photoelectron Spectroscopy ◽

Raw Material ◽

Mussel Shell ◽

Scanning Calorimetry ◽

Factors Affecting ◽

X Ray ◽

Before And After ◽

Freundlich Adsorption Isotherm ◽

Mussel Shells ◽

Shell Powder

As a natural biological adsorbent, shell powder is inexpensive, highly efficient, and does not leave any chemical residue; thus, it can be used to remove contaminants from water. In this study, we used mussel shells as a raw material to prepare an adsorbent. Scanning electron microscopy was used to observe the surface morphology of the mussel shell powder before and after calcination, and X-ray diffraction measurements, Fourier transform infrared spectroscopy, differential scanning calorimetry, X-ray photoelectron spectroscopy, and Brunauer–Emmett–Teller measurements were performed to analyze the structure and composition of calcined mussel shell powder. Characterization of the shell powder before and after calcination revealed a change from calcium carbonate to calcium oxide, as well as the formation of a surface porous structure. Using Pb(II) as a representative contaminant, various factors affecting the adsorption were explored, and the adsorption mechanism was analyzed. It was found that the adsorption is consistent with the Freundlich adsorption isotherm and the pseudo second-order model. The calcined mussel shell powder exhibits excellent adsorption for Pb(II), with an adsorption capacity reaching 102.04 mg/g.

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Impact of Crystal Habit on the Dissolution Rate and In Vivo Pharmacokinetics of Sorafenib Tosylate

Molecules ◽

10.3390/molecules26113469 ◽

2021 ◽

Vol 26 (11) ◽

pp. 3469

Author(s):

Chi Uyen Phan ◽

Jie Shen ◽

Kaxi Yu ◽

Jianming Mao ◽

Guping Tang

Keyword(s):

Dissolution Rate ◽

Photoelectron Spectroscopy ◽

Class Ii ◽

Crystal Habit ◽

Factors Affecting ◽

X Ray ◽

Bcs Class Ii ◽

Rate Limiting Step ◽

In Vivo Pharmacokinetics

The dissolution rate is the rate-limiting step for Biopharmaceutics Classification System (BCS) class II drugs to enhance their in vivo pharmacokinetic behaviors. There are some factors affecting the dissolution rate, such as polymorphism, particle size, and crystal habit. In this study, to improve the dissolution rate and enhance the in vivo pharmacokinetics of sorafenib tosylate (Sor-Tos), a BCS class II drug, two crystal habits of Sor-Tos were prepared. A plate-shaped crystal habit (ST-A) and a needle-shaped crystal habit (ST-B) were harvested by recrystallization from acetone (ACN) and n-butanol (BuOH), respectively. The surface chemistry of the two crystal habits was determined by powder X-ray diffraction (PXRD) data, molecular modeling, and face indexation analysis, and confirmed by X-ray photoelectron spectroscopy (XPS) data. The results showed that ST-B had a larger hydrophilic surface than ST-A, and subsequently a higher dissolution rate and a substantial enhancement of the in vivo pharmacokinetic performance of ST-B.

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Surface chemical composition and roughness as factors affecting the wettability of thermo-mechanically modified oak (Quercus robur L.)

Holzforschung ◽

10.1515/hf-2018-0022 ◽

2018 ◽

Vol 72 (11) ◽

pp. 993-1000 ◽

Cited By ~ 2

Author(s):

Agnieszka Laskowska ◽

Janusz W. Sobczak

Keyword(s):

Free Energy ◽

Surface Free Energy ◽

Photoelectron Spectroscopy ◽

Sessile Drop ◽

Glassy Polymers ◽

Work Of Adhesion ◽

Densified Wood ◽

Factors Affecting ◽

X Ray ◽

Densification Temperature

AbstractEuropean oak wood (W) was thermo-mechanically modified (TM) via densifying at 100 and 150°C and the surface properties of the TMW were investigated. The contact angle (CA) of the wood with the reference liquids water and diiodomethane was determined using the sessile drop method. The surface free energy of the TMW on tangential sections within the first 60 s after applying a drop was analyzed. The roughness parameters Ra and Rz parallel (‖) and perpendicular (⊥) to the grain were investigated. The wettability analysis showed that densified wood had a higher CA and lower work of adhesion and surface free energy than non-densified wood. An X-ray photoelectron spectroscopy [XPS or electron spectroscopy for chemical analysis (ESCA)] analysis showed that the oxygen to carbon atoms ratio (O/C ratio) of densified wood surface was lower than that of non-densified wood. The carbon C1-C2 atoms ratio (C1/C2 ratio) increased with increasing TM temperature. The results were interpreted as being that extractives migrate to the surface and amorphous and glassy polymers, i.e. lignin and hemicelluloses, in wood are rearranged. Increasing densification temperature makes TMW surfaces more hydrophobic.

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Structure-Property Relationships of BaCeO Perovskites for the Oxidative Dehydrogenation of Alkanes

MRS Proceedings ◽

10.1557/proc-497-21 ◽

1997 ◽

Vol 497 ◽

Cited By ~ 2

Author(s):

T. M. Nenoff ◽

N. B. Jackson ◽

J. E. Miller ◽

A. G. Sault ◽

D. Trudeil

Keyword(s):

Oxidative Dehydrogenation ◽

Photoelectron Spectroscopy ◽

Energy Savings ◽

Surface Oxygen ◽

Structure Property ◽

Weakly Bound ◽

Complete Combustion ◽

Factors Affecting ◽

X Ray ◽

Dehydrogenation Reactions

ABSTRACTThe oxidative dehydrogenation (ODH) reactions for the formation of two important organic feedstocks ethylene and propylene are of great interest because of the potential in capital and energy savings associated with these reactions. Theoretically, ODH can achieve high conversions of the starting materials (ethane and propane) at lower temperatures than conventional dehydrogenation reactions. The important focus in our study of ODH catalysts is the development of a structure-property relationship for catalyst with respect to selectivity, so as to avoid the more thermodynamically favorable combustion reaction. Catalysts for the ODH reaction generally consist of mixed metal oxides. Since for the most selective catalyst lattice oxygen is known to participate in the reaction, catalysts are sought with surface oxygen atoms that are labile enough to perform dehydrogenation, but not so plentiful or weakly bound as to promote complete combustion. Also, catalysts must be able to replenish surface oxygen by transport from the bulk.Perovskite materials are candidates to fulfill these requirements. We are studying BaCeO3 perovskites doped with elements such as Ca, Mg, and Sr. During the ODH of the alkanes at high temperatures, the perovskite structure is not retained and a mixture of carbonates and oxides is formed, as revealed by XRD. While the Ca doped materials showed enhanced total combustion activity below 600°C, they only showed enhanced alkene production at 700°C. Bulk structural and surface changes, as monitored by powder X-ray diffraction, and X-ray photoelectron spectroscopy are being correlated with activity in order to understand the factors affecting catalyst performance, and to modify catalyst formulations to improve conversion and selectivity.

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Synthesis of Iron Doped Zeolite Imidazolate Framework-8 and Its Remazol Deep Black RGB Dye Adsorption Ability

Journal of Chemistry ◽

10.1155/2017/5045973 ◽

2017 ◽

Vol 2017 ◽

pp. 1-18 ◽

Cited By ~ 10

Author(s):

Mai Thi Thanh ◽

Tran Vinh Thien ◽

Vo Thi Thanh Chau ◽

Pham Dinh Du ◽

Nguyen Phi Hung ◽

...

Keyword(s):

Photoelectron Spectroscopy ◽

Hydrothermal Process ◽

Dye Adsorption ◽

Specific Area ◽

Nitrogen Adsorption ◽

Vital Role ◽

Factors Affecting ◽

X Ray ◽

Effective Removal ◽

Iron Doped

Zeolite imidazole framework-8 (ZIF-8) and the iron doped ZIF-8 (Fe-ZIF-8) were synthesized by the hydrothermal process. The obtained materials were characteristic of X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), nitrogen adsorption/desorption isotherms, and atomic absorption spectroscopy (AAS). The results showed that the obtained Fe-ZIF-8 possessed the ZIF-8 structure with a large specific area. ZIF-8 and Fe-ZIF-8 were used for the removal of Remazol Deep Black (RDB) RGB dye from aqueous solutions. The various factors affecting adsorption such as pH, initial concentration, contact time, and temperature were investigated. The results showed that the introduction of iron into ZIF-8 provided a much larger adsorption capacity and faster adsorption kinetics than ZIF-8 without iron. The electrostatic interaction and π-π interaction between the aromatic rings of the RDB dye and the aromatic imidazolate rings of the adsorbent were responsible for the RDB adsorption. Moreover, the coordination of the nitrogen atoms and oxygen in carboxyl group in RDB molecules with the Fe2+ ions in the ZIF-8 framework played a vital role for the effective removal of RDB from aqueous solution.

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Heterogeneous UV/Fenton-Like Degradation of Methyl Orange Using Iron Terephthalate MIL-53 Catalyst

Journal of Chemistry ◽

10.1155/2020/1474357 ◽

2020 ◽

Vol 2020 ◽

pp. 1-13

Author(s):

Pham Dinh Du ◽

Huynh Thanh Danh ◽

Pham Ngoc Hoai ◽

Nguyen Mau Thanh ◽

Vo Thang Nguyen ◽

...

Keyword(s):

Catalytic Activity ◽

Methyl Orange ◽

Photoelectron Spectroscopy ◽

Nitrogen Adsorption ◽

High Catalytic Activity ◽

Potential Candidate ◽

Factors Affecting ◽

X Ray ◽

Activity Loss ◽

Degradation Of Methyl Orange

The synthesis and degradation of methyl orange (MO) in an ultraviolet-assisted heterogeneous Fenton-like process via the iron terephthalate (MIL-53) catalyst are demonstrated. MIL-53 material was characterized by means of X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FT-IR), UV-Vis diffuse reflectance spectra (DR-UV-Vis), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), and nitrogen adsorption/desorption isotherms. It was found that the obtained material shares an identical pattern of the MIL-53 structure with high crystallinity and also demonstrates the mesoporous phase with a pore diameter of around 4.2 nm and specific surface area, SBET, of 88.2 m2·g−1. MIL-53 with UV irradiation exhibits high catalytic activity for MO degradation by hydrogen peroxide. The factors affecting the efficiency of MO decomposition including pH of the solution, H2O2 concentration, catalyst dosage, initial MO concentration, and reaction temperature were addressed. The present catalyst is stable after four recycles with slight catalytic activity loss which makes it a potential candidate for environmental restoration.

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Activated mineral adsorbent for the efficient removal of Pb(II) and Cd(II) from aqueous solution: adsorption performance and mechanism studies

Water Science & Technology ◽

10.2166/wst.2020.453 ◽

2020 ◽

Vol 82 (9) ◽

pp. 1896-1911

Author(s):

Tao Zheng ◽

Xiaohui Zhou ◽

Jing Guo ◽

Chubin Zhong ◽

Yaochi Liu

Keyword(s):

Photoelectron Spectroscopy ◽

Adsorption Process ◽

Ph Value ◽

Potassium Feldspar ◽

X Ray Diffraction ◽

Batch Mode ◽

Factors Affecting ◽

X Ray ◽

Adsorption Performance ◽

Adsorption Removal

Abstract Activated mineral adsorbent (AMA) was prepared via double salts (Na2SO4 and CaCO3) heat treatment activation of solid-state potassium feldspar. Adsorption performance of AMA for Cd(II) and Pb(II) was investigated by batch mode and factors affecting adsorption including pH value, initial concentration of adsorbate, contact time, adsorbent dosage and temperature on adsorption performance for Cd(II) and Pb(II) were studied. The results indicated that the adsorption process was pH dependent, endothermic and spontaneous. When the adsorption process of Cd(II) and Pb(II) on AMA reached equilibrium, the maximum saturated adsorption capacities were 263.16 and 303.03 mg/g for Cd(II) and Pb(II) ions, respectively, showing higher adsorption removal efficiency. The Langmuir adsorption isotherm and pseudo second kinetic equation could well fit the adsorption process of Cd(II) and Pb(II) by AMA. Besides, Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) techniques were also performed to further reveal the adsorption mechanism. The results indicated that ion exchange, precipitation and adsorption played an important role in adsorption process. From the investigation, it was concluded that AMA was an excellent adsorbent with the advantages of environment-friendly, inexpensive, facile preparation and higher adsorption capacity of toxic Cd(II) and Pb(II) ions.

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One-Step Cohydrothermal Synthesis of Nitrogen-Doped Titanium Oxide Nanotubes with Enhanced Visible Light Photocatalytic Activity

International Journal of Photoenergy ◽

10.1155/2012/391958 ◽

2012 ◽

Vol 2012 ◽

pp. 1-9 ◽

Cited By ~ 11

Author(s):

Cheng-Ching Hu ◽

Tzu-Chien Hsu ◽

Li-Heng Kao

Keyword(s):

Photocatalytic Activity ◽

Visible Light ◽

Photoelectron Spectroscopy ◽

Nitrogen Adsorption ◽

Raw Material ◽

Factors Affecting ◽

X Ray ◽

Nitrogen Doped ◽

Visible Light Photocatalytic Activity ◽

Visible Light Photocatalytic

Nitrogen-doped TiO2nanotubes with enhanced visible light photocatalytic activity have been synthesized using commercial titania P25 as raw material by a facile P25/urea cohydrothermal method. Morphological and microstructural characteristics were conducted by transmission electron microscopy, powder X-ray diffraction, and nitrogen adsorption/desorption isotherms; chemical identifications were performed using X-ray photoelectron spectroscopy, and the interstitial nitrogen linkage to the TiO2nanotubes is identified. The photocatalytic activity of nitrogen-doped TiO2nanotubes, evaluated by the decomposition of rhodamine B dye solution under visible light using UV-vis absorption spectroscopy, is found to exhibit ~ four times higher than that of P25 and undoped titanate nanotubes. Factors affecting the photocatalytic activity are analyzed; it is found that the nitrogen content and surface area, rather than the crystallinity, are more crucial in affecting the photocatalytic efficiency of the nitrogen-doped TiO2nanotubes.

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