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1. 1,2,3,4-Tetrahydropyrimidine Derivative for Selective and Fast Uptake of Cadmium Ions from Aqueous Solution

Author:
Mohamed Ould M’hamed; Lotfi Khezami
Source:
Environments 2019 v.6 no.6 pp. -
ISSN:
2076-3298
Subject:
adsorption; aqueous solutions; cadmium; endothermy; entropy; equations; heavy metals; heterocyclic compounds; metal ions; milling; nuclear magnetic resonance spectroscopy; pH; sorption isotherms; toxicity
Abstract:
... The aim of this work was to evaluate the performance of a 1,2,3,4-tetrahydropyrimidine derivative as a powerful heterocyclic compound for the elimination of Cd(II) ions from aqueous solutions. The tetrahydropyrimidine derivative was prepared during 30 min of milling by planetary ball mill with a ball-to-powder mass ratio of 8:1 and a rotation speed of 750 rpm. Nuclear magnetic resonance (NMR) and ...
DOI:
10.3390/environments6060068

2. 2,4-D adsorption from agricultural subsurface drainage by canola stalk-derived activated carbon: insight into the adsorption kinetics models under batch and column conditions

Author:
Mohammad Javad Amiri; Reza Roohi; Mohammad Arshadi; Alireza Abbaspourrad
Source:
Environmental science and pollution research international 2020 v.27 no.14 pp. 16983-16997
ISSN:
0944-1344
Subject:
2,4-D; acetone; activated carbon; adsorbents; adsorption; aromatic compounds; calcium; canola; chemical reactions; drainage water; equations; kinetics; pH; pollution; porous media; research; steam; subsurface drainage
Abstract:
... In this study, the experimental and kinetic modeling investigations were performed to evaluate the ability of mesoporous and microporous canola stalk-derived activated carbon (CSAC) on 2,4-dichlorophenoxyacetic acid (2,4-D) removal from synthetic and natural water in both batch and continuous systems. Three empirical models (pseudo-first-order equation (PFOE), pseudo-second-order equation (PSOE), ...
DOI:
10.1007/s11356-020-08211-7

3. 3D-printed highly porous and reusable chitosan monoliths for Cu(II) removal

Author:
Dongxing Zhang; Junfeng Xiao; Qiuquan Guo; Jun Yang
Source:
Journal of materials science 2019 v.54 no.8 pp. 6728-6741
ISSN:
0022-2461
Subject:
EDTA (chelating agent); adsorbents; adsorption; chitosan; copper; cost effectiveness; desorption; equations; heavy metals; human health; metal ions; models; moieties; pH; pollution; pollution control; sorption isotherms; surface area; working conditions
Abstract:
... Removal of heavy metal pollution has received considerable research attention due to its severe effects on human health. In the present study, for the first time, a reusable monolithic 3D porous adsorbing filter was fabricated by integrating 3D printing technique with a natural adsorbent (chitosan), which is a low-cost and highly effective solution for heavy metal removal. The –NH₂ and –OH functio ...
DOI:
10.1007/s10853-019-03332-y

4. A Colloidal Description of Intermolecular Interactions Driving Fibril–Fibril Aggregation of a Model Amphiphilic Peptide

Author:
Owczarz Marta; Motta Anna C.; Morbidelli Massimo; Arosio Paolo
Source:
Langmuir 2015 v.31 no.27 pp. 7590-7600
ISSN:
1520-5827
Subject:
activation energy; amyloid; cations; chemical interactions; dispersions; energy; equations; ionic strength; kinetics; light scattering; models; pH; peptides; salt concentration; screening; solvents; surfactants
Abstract:
... We apply a kinetic analysis platform to study the intermolecular interactions underlying the colloidal stability of dispersions of charged amyloid fibrils consisting of a model amphiphilic peptide (RADA 16-I). In contrast to the aggregation mechanisms observed in the large majority of proteins and peptides, where several elementary reactions involving both monomers and fibrils are present simultan ...
DOI:
10.1021/acs.langmuir.5b01110

5. A Comparison of Water Treatment Sludge and Red Mud as Adsorbents of As and Se in Aqueous Solution and Their Capacity for Desorption and Regeneration

Author:
Ya-Feng Zhou; Richard J. Haynes
Source:
Water, air, and soil pollution 2012 v.223 no.9 pp. 5563-5573
ISSN:
0049-6979
Subject:
adsorbents; adsorption; alum; aqueous solutions; desorption; equations; heavy metals; models; pH; seawater; sludge; streams; wastewater; water treatment
Abstract:
... The adsorption of As(III), As(V), Se(IV) and Se(VI) by seawater neutralized red mud and alum water treatment sludge was investigated and compared using the batch adsorption technique. For water treatment sludge, adsorption of As(V), Se(IV) and Se(VI), at equimolar concentrations of added metalloid, declined with increasing pH. The decline was rapid above pH 4.0 for Se(VI), above pH 5.0 for Se(IV) ...
DOI:
10.1007/s11270-012-1296-0

6. A Computer Simulation of Fe(III) and Fe(II) Complexation in Limited Nutrient Solution: I. Program Development and Testing

Author:
A. P. Schwab; W. L. Lindsay
Source:
Soil Science Society of America journal 1989 v.53 no.1 pp. 29-34
ISSN:
0361-5995
Subject:
Glycine max; calcium; chelates; chelating agents; computer simulation; equations; iron; models; nutrient deficiencies; nutrient solutions; pH; program planning; redox potential; roots; soybeans
Abstract:
... The mechanism by which Fe-stressed roots increase Fe availability was determined with the assistance of a computer model (written in PASCAL) that predicted the effects of redox and pH on the stability of Fe chelates. The program solves a series of simultaneous equilibrium equations to calculate the concentrations of all species in a nutrient solution containing Fe, Ca, and two competing chelating ...
DOI:
10.2136/sssaj1989.03615995005300010006x

7. A Facile One-Pot Strategy to Functionalize Graphene Oxide with Poly(amino-phosphonic Acid) Derived from Wasted Acrylic Fibers for Effective Gd(III) Capture

Author:
Weiyan Yin; Xinyu Zhan; Pai Fang; Minggui Xia; Junxia Yu; Ru-an Chi
Source:
ACS sustainable chemistry & engineering 2019 v.7 no.24 pp. 19857-19869
ISSN:
2168-0485
Subject:
adsorbents; adsorption; aqueous solutions; endothermy; equations; gadolinium; graphene; graphene oxide; magnetism; metal ions; pH; recycling; sorption isotherms; synergism; thermodynamics; toxicity; wastes
Abstract:
... Today, toxic rare earth metal ions contamination and huge volume of waster acrylic fibers (WAFs) have caused serious environmental problems, which make the development and implementation of feasible and sustainable methods to recycle the wastes of high practical significance. Herein, we propose, for the first time, that using WAFs as a poly(amino-phosphonic acid) (PAPA) precursor to functionalize ...
DOI:
10.1021/acssuschemeng.9b05221

8. A General Liquid–Liquid Partitioning Equation and Its Consequences: Learning from the pH Dependent Extraction of a Pharmaceutical Intermediate

Author:
Ian W. Ashworth; Rebecca E. Meadows
Source:
Journal of organic chemistry 2018 v.83 no.7 pp. 4270-4274
ISSN:
1520-6904
Subject:
chemical reactions; chemical structure; equations; learning; liquid-liquid extraction; models; organic chemistry; organobromine compounds; pH
Abstract:
... We observed that the product of a Buchwald–Hartwig coupling reaction extracted from the organic phase easily, relative to the starting aryl bromide as the pH was lowered. This was surprising given the similarity of their pKₐ's. The product’s extraction curve was also significantly steeper than expected. A consideration of the relevant equilibria, including all three of the product’s pKₐ's, led to ...
DOI:
10.1021/acs.joc.8b00309

9. A Gompertz Model Approach to Microbial Inactivation Kinetics by High-Pressure Processing Incorporating the Initial Counts, Microbial Quantification Limit, and Come-Up Time Effects

Author:
Vinicio Serment-Moreno; Claudio Fuentes; José Ángel Guerrero-Beltrán; José Antonio Torres; Jorge Welti-Chanes
Source:
Food and bioprocess technology 2017 v.10 no.8 pp. 1495-1508
ISSN:
1935-5130
Subject:
bacteria; bacterial spores; chemical concentration; data collection; enzyme activity; equations; high pressure treatment; kinetics; logit analysis; pH
Abstract:
... During come-up time (CUT), the time to reach a desired processing pressure, isobaric-isothermal conditions cannot be assumed in the estimation of kinetic parameters for the design of commercial high-pressure processing (HPP) treatments. Since CUT effects on microbial population, enzyme activity, and chemical concentration are often ignored, kinetic models incorporating the non-isobaric and non-iso ...
DOI:
10.1007/s11947-017-1916-1

10. A Mechanistic Approach for the Synthesis of Carboxylate-Rich Carbonaceous Biomass-Doped Lanthanum-Oxalate Nanocomplex for Arsenate Adsorption

Author:
Subbaiah Muthu Prabhu; Chitiphon Chuaicham; Keiko Sasaki
Source:
ACS sustainable chemistry & engineering 2018 v.6 no.5 pp. 6052-6063
ISSN:
2168-0485
Subject:
Fourier transform infrared spectroscopy; adsorbents; adsorption; ambient temperature; arsenates; arsenic; biomass; carbon; coprecipitation; electrostatic interactions; equations; hydrogen bonding; lanthanum; ligands; oxalates; pH; protocols; sucrose; waste disposal
Abstract:
... Considering the protocol of “zero-alkaline waste disposal” for green and arsenic-free environment, lanthanum (La³⁺)-based MOF-like complex materials were designed, and the complex materials have been employed as adsorbent for AsO₄³– adsorption from water. The sucrose-derived porous carbon (SPC)@La-oxalate complex was prepared by a simple one-pot coprecipitation method at room temperature, where ox ...
DOI:
10.1021/acssuschemeng.7b04678

11. A Model of Uranium Uptake by Plant Roots Allowing for Root-Induced Changes in the soil

Author:
Andrea Boghi; Tiina Roose; Guy J. D. Kirk
Source:
Environmental science & technology 2018 v.52 no.6 pp. 3536-3545
ISSN:
1520-5851
Subject:
acids; carbon dioxide; chemical bases; empirical models; environmental science; equations; geometry; ligands; nitrogen; pH; rhizosphere; roots; soil solution; soil types; sorption; uranium
Abstract:
... We develop a model with which to study the poorly understood mechanisms of uranium (U) uptake by plants. The model is based on equations for transport and reaction of U and acids and bases in the rhizosphere around cylindrical plant roots. It allows for the speciation of U with hydroxyl, carbonate, and organic ligands in the soil solution; the nature and kinetics of sorption reactions with the soi ...
DOI:
10.1021/acs.est.7b06136

12. A New Study on the Steady Shear Flow, Thermal and Functional Properties of Beet Pulp Carboxymethyl Cellulose

Author:
Sobhan Savadkoohi; Gholamreza Mesbahi; Mehrdad Niakousari; Asgar Farahnaky
Source:
Journal of food processing and preservation 2014 v.38 no.5 pp. 2117-2128
ISSN:
0145-8892
Subject:
beet pulp; blood serum; carboxymethylcellulose; differential scanning calorimetry; equations; food processing wastes; functional properties; heat production; hydrocolloids; industry; ketchup; pH; production costs; raw materials; sodium chloride; storage time; viscosity
Abstract:
... The current work presents a study of rheological, thermal and functional properties of carboxymethyl cellulose (CMC) produced from beet pulp compared with commercial CMC primarily at low‐solid concentrations. Differential scanning calorimetry (DSC) results demonstrated two endothermic peaks around 104, 173C and two exothermic peaks at 307 and 361C. The flow properties of produced CMC were performe ...
DOI:
10.1111/jfpp.12192

13. A Novel Approach for the Removal of Lead(II) Ion from Wastewater Using Mucilaginous Leaves of Diceriocaryum eriocarpum Plant

Author:
Joshua N. Edokpayi; John O. Odiyo; Titus A. M. Msagati; Elizabeth O. Popoola
Source:
Sustainability 2015 v.7 no.10 pp. 14026-14041
ISSN:
2071-1050
Subject:
Machaeranthera; adsorbents; adsorption; aqueous solutions; equations; human health; hydrochloric acid; lead; leaves; models; moieties; pH; sodium hydroxide; sorption isotherms; toxicity; waste lagoons; wastewater
Abstract:
... Lead(II) ion is a very toxic element known to cause detrimental effects to human health even at very low concentrations. An adsorbent prepared using mucilaginous leaves from Diceriocaryum eriocarpum plant (DEP) was used for the adsorption of lead(II) ion from aqueous solution. Batch experiments were performed on simulated aqueous solutions under optimized conditions of adsorbent dosage, contact ti ...
DOI:
10.3390/su71014026

14. A Novel Cross-Linked Magnetic Hydroxyapatite/Chitosan Composite: Preparation, Characterization, and Application for Ni(II) Ion Removal from Aqueous Solution

Author:
Van Thuan Le; Van Dat Doan; Dinh Duc Nguyen; Hoai Thuong Nguyen; Quoc Phu Ngo; Thi Kieu Ngan Tran; Hoang Sinh Le
Source:
Water, air, and soil pollution 2018 v.229 no.3 pp. 101
ISSN:
0049-6979
Subject:
EDTA (chelating agent); Fourier transform infrared spectroscopy; X-ray diffraction; adsorbents; adsorption; ambient temperature; aqueous solutions; bones; cattle; chitosan; crosslinking; desorption; equations; green tea; heat production; hydrochloric acid; hydroxyapatite; ions; magnetism; nickel; pH; recycling; scanning electron microscopy; shrimp; slags; sorption isotherms; steel; wastewater
Abstract:
... In this study, a novel magnetic hydroxyapatite/chitosan composite (HA/Fe₃O₄/CS) prepared from steel slag, shrimp shells, and bovine bones, and then cross-linked with a green tea extract was used as an adsorbent for Ni(II) ion removal from aqueous solution. Various techniques (SEM, FTIR, XRD, VSM) were used to characterize the adsorbent. Batch experiments were conducted to investigate the adsorptio ...
DOI:
10.1007/s11270-018-3762-9

15. A Sensitive and Simple Impedance Sensing Strategy for Glutathione and Glutathione Reductase Activity Detection

Author:
Yaohui Wu; Lun Jiang; Ge Ning; Lei Chu; Wen Liu; Yonghong Wang; Yunlin Zhao
Source:
Journal of analytical chemistry 2019 v.74 no.5 pp. 505-512
ISSN:
1061-9348
Subject:
NADP (coenzyme); adenine; colorimetry; detection limit; electrochemistry; electrodes; enzyme activity; equations; glutathione; glutathione-disulfide reductase; gold; medicine; oxidation; pH
Abstract:
... A simple electrochemical method for detecting glutathione reductase was developed in this work. It was observed that the impedance of electrode increased obviously after the electrode modification by glutathione, and the value of impedance was closely related to the reduced glutathione (GSH) concentration. Based on the fact that glutathione reductase (GR) could catalyze oxidized glutathione (GSSG) ...
DOI:
10.1134/S1061934819050101

16. A Study on Using Date Palm Fibers and Leaf Base of Palm as Adsorbents for Pb(II) Ions from Its Aqueous Solution

Author:
Al-Haidary, Abdul Muhsen A.; Zanganah, Faeeza H. H.; Al-Azawi, Sahar R. F.; Khalili, Fawwaz I.; Al-Dujaili, Ammar Hani
Source:
Water, air, and soil pollution 2011 v.214 no.1-4 pp. 73-82
ISSN:
0049-6979
Subject:
Gibbs free energy; adsorbents; adsorption; aqueous solutions; energy; entropy; equations; ionic strength; ions; lead; models; pH; particle size; petioles; temperature
Abstract:
... The adsorption of lead onto date palm fibers (palm fibers) and leaf base of palm (petiole) has been examined in aqueous solution by considering the influence of various parameters such as contact time, solution pH, adsorbent dosage, particle sizes, ionic strength, and temperature. The adsorption of Pb(II) increased with an increase of contact time. The optimal range of pH for Pb(II) adsorption is ...
DOI:
10.1007/s11270-010-0405-1

17. A chip-type thin-layer electrochemical cell coupled with capillary electrophoresis for online separation of electrode reaction products

Author:
Jian-Bo He; Ting Cui; Wen-Wen Zhang; Ning Deng
Source:
Analytica chimica acta 2013 v.786 pp. 159-165
ISSN:
0003-2670
Subject:
capillary electrophoresis; electrochemistry; electrodes; electrolysis; electrolytes; equations; pH; quercetin
Abstract:
... A coupling technique of thin-layer electrolysis with high-performance capillary electrophoresis/UV–vis technique(EC/HPCE/UV–vis) is developed for online separation and determination of electrode reaction products. A chip-type thin-layer electrolytic (CTE) cell was designed and fabricated, which contains a capillary channel and a background electrolyte reservoir, allowing rapid electrolysis, direct ...
DOI:
10.1016/j.aca.2013.05.035

18. A clean production process for edible oil removal from wastewater using an electroflotation with horizontal arrangement of mesh electrodes

Author:
Amir Mirshafiee; Abbas Rezaee; Rasol Sarraf Mamoory
Source:
Journal of cleaner production 2018 v.198 pp. 71-79
ISSN:
0959-6526
Subject:
X-radiation; X-ray diffraction; byproducts; chemical oxygen demand; cooking fats and oils; electrochemistry; electrodes; electrolytes; equations; fatty acids; fluorescence; gas chromatography; ionization; kinetics; pH; scanning electron microscopy; sludge; sodium chloride; stainless steel; wastewater; wastewater treatment
Abstract:
... In this study, a novel electrochemical process using horizontal arrangement of stainless steel mesh electrodes was proposed to improve the flotation rate of oily wastewater treatment with emphasis on kinetic analysis and by-products removal. The effect of the current density (1.64–6.54 mA/cm²), initial pH (3–9), electrode distance (1–3 cm), supporting electrolyte (50–350 mg/l), and initial concent ...
DOI:
10.1016/j.jclepro.2018.06.201

19. A comparative evaluation of the liquid–liquid extraction and pertraction efficiency of a both-side diglycolamide-functionalized calix[4]arene with analogous upper and lower-rim calixarenes for actinide separations

Author:
P.K. Mohapatra; D.R. Rout; M. Iqbal; J. Huskens; W. Verboom
Source:
Journal of membrane science 2013 v.444 no. pp. 268-275
ISSN:
0376-7388
Subject:
EDTA (chelating agent); aromatic hydrocarbons; cesium; diffusivity; equations; ions; liquid membranes; liquid-liquid extraction; nitric acid; pH; solvents; strontium
Abstract:
... A lower-rim (L-I), an upper-rim (L-II), and a both-side (L-III) diglycolamide-functionalized calix[4]arene were evaluated for the extraction of actinide ions such as UO₂ ²⁺, Pu⁴⁺, and Am³⁺ and fission product element ions such as Eu³⁺, Cs⁺, and Sr²⁺ from dilute nitric acid feed solutions. Conditions for quantitative extraction and stripping were found out and the kinetics of it were investigated f ...
DOI:
10.1016/j.memsci.2013.05.044

20. A comprehensive adsorption study and modeling of antibiotics as a pharmaceutical waste by graphene oxide nanosheets

Author:
Rahele Rostamian; Hassan Behnejad
Source:
Ecotoxicology and environmental safety 2018 v.147 pp. 117-123
ISSN:
0147-6513
Subject:
adsorption; aqueous solutions; ciprofloxacin; doxycycline; drugs; equations; graphene oxide; kinetics; models; nanosheets; pH; temperature; wastes
Abstract:
... The adsorption behavior of tetracycline (TCN), doxycycline (DCN) as the most common antibiotics in veterinary and ciprofloxacin (CPN) onto graphene oxide nanosheets (GOS) in aqueous solution was evaluated. The four factors influencing the adsorption of antibiotics (initial concentration, pH, temperature and contact time) were studied. The results showed that initial pH ∼ 6 to 7 and contact time ∼ ...
DOI:
10.1016/j.ecoenv.2017.08.019