U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

PubAg

Main content area

You searched for: Subject anions Remove constraint Subject: anions Subject X-ray diffraction Remove constraint Subject: X-ray diffraction
Start Over

Search

832  Search Results

« Previous | 1 - 20 of 832 |
Number of results to display per page

Search Results

1. Highly Stable Polyoxovanadate-Based Zn–MOF with Dual Active Sites as a Solvent-free Catalyst for C–C Bond Formation

Author:
Hongrui Tian; Shumei Liu; Zhong Zhang; Tianyi Dang; Ying Lu; Shuxia Liu
Source:
ACS sustainable chemistry & engineering 2021 v.9 no.12 pp. 4660-4667
ISSN:
2168-0485
Subject:
Lewis acids; Lewis bases; X-ray diffraction; anions; catalysts; catalytic activity; cations; condensation reactions; green chemistry; molecular weight; synergism; zinc
Abstract:
... A polyoxovanadate-based zinc–organic framework, [Zn(bix)]{V₂O₆}(V-Zn-MOF, bix = 1,4-bis(imidazole-1-ylmethyl)benzene), was successfully synthesized under hydrothermal conditions. Single-crystal X-ray analysis reveals that the V-Zn-MOF contains {V₂O₆}ₙ²ⁿ– polyanion chains and [Zn(bix)]²⁺ cation frameworks with open zinc metal sites, which endows V-Zn-MOF-rich Lewis base and acid sites. Considering ...
DOI:
10.1021/acssuschemeng.1c00389

2. A Tetraindeno-Fused Bis(anthraoxa)quinodimethane with Nine Consecutively Fused Six-Membered Rings

Author:
Johnathan Joo Cheng Lee; Shaoqiang Dong; Albert Ong; Yi Han; Jishan Wu; Chunyan Chi
Source:
Organic letters 2021 v.23 no.8 pp. 3027-3031
ISSN:
1523-7052
Subject:
X-ray diffraction; anions; photostability
Abstract:
... A tetraindeno-fused bis(anthraoxa)quinodimethane RBR with nine consecutively fused six-membered rings in a row was synthesized. Its structure was confirmed by X-ray crystallographic analysis and NMR measurement. Compared with an unfused analogue ABA, the indeno fusion onto the zigzag edges not only enhanced the photostability but also dramatically tuned the electronic properties. Due to the existe ...
DOI:
10.1021/acs.orglett.1c00705

3. Adsorption of low concentrations of bromide ions from water by cellulose-based beads modified with TEMPO-mediated oxidation and Fe(III) complexation

Author:
Shengpeng Liu; Gen Cheng; Yun Xiong; Yigang Ding; Xiaogang Luo
Source:
Journal of hazardous materials 2020 v.384 pp. 121195
ISSN:
0304-3894
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; acidity; adsorbents; adsorption; anions; aqueous solutions; bromides; carboxylation; cellulose; electrostatic interactions; energy; energy-dispersive X-ray analysis; heat production; iron; kinetics; models; oxidation; scanning electron microscopy; thermogravimetry; wastewater
Abstract:
... Due to strong activity, it is very difficult to remove low concentrations of bromide in medical wastewater by traditional method, thus highly effective and greener adsorbents should be utilized to design. In this work, the cellulose beads (CBs) were modified by the TEMPO-mediated oxidation and then bonded with Fe³⁺ to fabricate Fe(III)-complexed carboxylated cellulose beads (Fe-CCBs) adsorbents. S ...
DOI:
10.1016/j.jhazmat.2019.121195

4. Application of ZnO nanorods doped with Cu for enhanced sonocatalytic removal of Cr(VI) from aqueous solutions

Author:
Kazem Godini; Mahsa Tahergorabi; Mohammad Naimi-Joubani; Mehdi Shirzad-Siboni; Jae-Kyu Yang
Source:
Environmental science and pollution research international 2020 v.27 no.3 pp. 2691-2706
ISSN:
0944-1344
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; X-ray photoelectron spectroscopy; anions; aqueous solutions; catalysts; chromium; citric acid; copper; coprecipitation; electric power; electroplating; energy-dispersive X-ray analysis; hydrogen peroxide; nanorods; pH; scanning electron microscopy; sonocatalysis; ultrasonics; wastewater; zinc oxide
Abstract:
... The aim of this research was to develop a simple and inexpensive process for reduction of Cr(VI) to Cr(III). Zinc oxide nanoparticles were synthesized with an easy co-precipitation procedure, and the addition of Cu²⁺ doping agent effectively enhanced the Cr(VI) reduction in the presence of ultrasound (US). XRD, FT-IR, FE-SEM, EDX, VSM, and XPS were used to determine the structural specifications o ...
DOI:
10.1007/s11356-019-07165-9

5. Application of metallic nanoparticle-biochars with ionic liquids for thermal transfer fluids

Author:
Hsin-Liang Huang; Zi-Hao Huang; Yi-Cheng Chu; Hong-Ping Lin; Yun-Jung Chang
Source:
Chemosphere 2020 v.250 pp. 126219
ISSN:
0045-6535
Subject:
X-ray diffraction; adsorption; anions; biochar; cations; chlorides; copper; copper hydroxide; cupric oxide; heat transfer; hydrogen bonding; imidazole; ionic liquids; irradiation; lighting; moieties; nanoparticles; nanosilver; nuclear magnetic resonance spectroscopy; silver; solar collectors; solar radiation; temperature; thermal properties
Abstract:
... Ionic liquids (ILs (1-butyl-3-methylimidazolium chloride ([C₄mim][Cl]) and 1-butyl-3-methylimidazolium tetrafluoroborate ([C₄mim][BF₄]))) were used as heat transfer fluids for solar thermal collectors. The additive of ILs was biochar containing copper and silver nanoparticles (Cu–Ag/biochar) to improve the adsorption of solar irradiation and thermal conductivities. After impregnation and reduction ...
DOI:
10.1016/j.chemosphere.2020.126219

6. As(III) removal from aqueous solution by katoite (Ca3Al2(OH)12)

Author:
Lin Sha; Zhemin Zou; Jun Qu; Xinfei Li; Yiyi Huang; Chenjie Wu; Zhigao Xu
Source:
Chemosphere 2020 v.260 pp. 127555
ISSN:
0045-6535
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; X-ray photoelectron spectroscopy; adsorption; agitation; anions; aqueous solutions; arsenites; drinking water; groundwater; irrigation; manufacturing; thermogravimetry; water purification
Abstract:
... As (III) is widely distributed in groundwater which is relatively harder to be removed comparing to As (V). Co-grinding Ca(OH)₂ with Al(OH)₃ was conducted to manufacture katoite (Ca₃Al₂(OH)₁₂) for the complete removal of As(III) (concentration below drinking water standard of WHO (<10 ppb)) during one-step agitation operation. X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR ...
DOI:
10.1016/j.chemosphere.2020.127555

7. Ba(B₂OF₃(OH)₂)₂ with well-ordered OH/F anions and a unique B₂OF₃(OH)₂ dimer

Author:
Minqiang Gai; Ying Wang; Tinghao Tong; Liying Wang; Zhihua Yang; Xin Zhou; Shilie Pan
Source:
Chemical communications 2020 v.56 no.22 pp. 3301-3304
ISSN:
1364-548X
Subject:
X-ray diffraction; anions; barium; chemical reactions; crystal structure; crystals; hydrogen; minerals; probability
Abstract:
... In minerals and artificial crystals, the OH and F groups often coexist and have a high probability of disordered structure. The OH/F position cannot be determined accurately in the crystal structure only by the direct X-ray diffraction method because of the poor contrast between O and F and the weak diffractivity of hydrogen atoms. In this work, a new fluorooxoborate Ba[B₂OF₃(OH)₂]₂, with a size o ...
DOI:
10.1039/c9cc06532f

8. CBD grown pure and Ce-doped ZnO nanorods: Comparison of their photocatalytic degrading efficiencies on AR88 azo dye under visible light irradiation

Author:
Memnune Kardeş; Gizem Başaran Dindaş; Hüseyin Cengiz Yatmaz; Nadir Dizge; Koray Öztürk
Source:
Colloids and surfaces 2020 v.607 pp. 125451
ISSN:
0927-7757
Subject:
X-ray diffraction; ambient temperature; anions; aqueous solutions; azo dyes; ceric oxide; cerium; emissions factor; irradiation; nanorods; photocatalysis; photoluminescence; zinc; zinc oxide
Abstract:
... A seed-mediated approach was utilized in growing of pure and cerium-doped ZnO nanorods via a low-temperature (∼95 °C) chemical bath deposition (CBD) method. The aqueous solutions with different Ce molar ratios (Ce/(Ce + Zn), which were equal to 0, 0.01, 0.05, 0.1 or 0.2) were prepared. An excess amount of cerium ions (≥0.1 in the present study) caused the formation of a new phase, identified as Ce ...
DOI:
10.1016/j.colsurfa.2020.125451

9. Carbon quantum dots functionalized agarose gel matrix for in solution detection of nonylphenol

Author:
Sanju Singh; Preeti Nigam; Aisha Pednekar; Souvik Mukherjee; Abhishek Mishra
Source:
Environmental technology 2020 v.41 no.3 pp. 322-328
ISSN:
1479-487X
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; agarose; algae; anions; aquatic environment; carbon quantum dots; detection limit; fluorescence; gels; moieties; nonylphenols; pH; rapid methods; toxicity; vibration; wastes; water solubility
Abstract:
... Nonylphenol, an endocrine disrupter, is widely released to the aquatic environment, which is accumulative and extremely toxic to aquatic organisms. Here, we report a simple and cost-effective large-scale green synthesis of water-soluble highly fluorescent carbon quantum dots (CQDs) from marine biowaste (offshore washed algae) which gets quenched strongly in the presence of nonylphenol. These CQDs ...
DOI:
10.1080/09593330.2018.1498133

10. Cationic metal-organic framework based mixed-matrix membrane for extraction of phenoxy carboxylic acid (PCA) herbicides from water samples followed by UHPLC-MS/MS determination

Author:
Gege Wu; Jiping Ma; Shasha Wang; Huining Chai; Liang Guo; Jinhua Li; Abbas Ostovan; Yafeng Guan; Lingxin Chen
Source:
Journal of hazardous materials 2020 v.394 pp. 122556
ISSN:
0304-3894
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; X-ray photoelectron spectroscopy; adsorption; anions; carboxylic acids; coordination polymers; detection limit; electrostatic interactions; herbicides; ionic strength; nuclear magnetic resonance spectroscopy; pH; pollutants; scanning electron microscopy; tandem mass spectrometry; thermoplastics; ultra-performance liquid chromatography
Abstract:
... A novel kind of cationic metal-organic framework(MOF) based mixed-matrix membrane(MMM) namely cationic MOF-MMM was firstly designed and used for simultaneous dispersive membrane extraction(DME) of six phenoxy carboxylic acid(PCA) herbicides from water samples followed by determination using ultrahigh-performance liquid chromatography tandem mass spectrometry. The cationic MOF-MMM was synthesized b ...
DOI:
10.1016/j.jhazmat.2020.122556

11. Common Anions Affected Removal of Carbon Tetrachloride in Groundwater Using Granular Sponge Zerovalent Iron

Author:
Xueqiang Zhu; Baoping Han; Qiyan Feng
Source:
Water, air, and soil pollution 2020 v.231 no.4 pp. 138
ISSN:
0049-6979
Subject:
X-ray diffraction; X-ray photoelectron spectroscopy; anions; bicarbonates; carbon tetrachloride; chlorides; corrosion; energy-dispersive X-ray analysis; ferric oxide; groundwater; iron; oxidants; remediation; scanning electron microscopy; sulfates; uncertainty
Abstract:
... Significant attention has been devoted over the past two decades to research and field applications of zerovalent iron (ZVI) technologies for groundwater remediation. The uncertainty of ZVI effectiveness under complex subsurface environment will affect the application of ZVI remedial techniques. The effects of groundwater common anions Cl⁻, SO₄²⁻, and HCO₃⁻ on CCl₄ degradation by sponge ZVI were i ...
DOI:
10.1007/s11270-020-04494-1

12. Effect of simulated acid rain on stability of arsenic calcium residue in residue field

Author:
Jiangchi Fei; Jingjing Ma; Jinqin Yang; Yanjie Liang; Yong Ke; Liwei Yao; Yuancheng Li; Degang Liu; Xiaobo Min
Source:
Environmental geochemistry and health 2020 v.42 no.3 pp. 769-780
ISSN:
0269-4042
Subject:
X-ray diffraction; acid rain; acidity; anions; arsenic; calcium; calcium arsenate; chlorides; crystallization; environmental hazards; heavy metals; industrial wastes; leachates; leaching; particle size; scanning electron microscopy; sulfates
Abstract:
... In recent years, acid rain had a serious negative impact on the leaching behavior of industrial waste residue. Researches were mainly focused on the environmental hazards of heavy metal in the leachate, but ignored the effects of heavy metal speciation on the stability of waste residue in the subsequent stabilization process. In this study, the unstable calcium–arsenic compounds in the arsenic cal ...
DOI:
10.1007/s10653-019-00273-y

13. Effect of the Ionic Liquid Structure on the Melt Processability of Polyacrylonitrile Fibers

Author:
Halie J. Martin; Huimin Luo; Hao Chen; Chi-Linh Do-Thanh; Logan T. Kearney; Richard Mayes; Amit K. Naskar; Sheng Dai
Source:
ACS applied materials & interfaces 2020 v.12 no.7 pp. 8663-8673
ISSN:
1944-8252
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; anions; carbon; carbon fibers; carbonization; chemical structure; chlorides; differential scanning calorimetry; ionic liquids; mechanical properties; mechanical testing; melting; polyacrylonitrile; scanning electron microscopy; thermogravimetry; toxicity; vapor pressure
Abstract:
... The production of high-strength carbon fibers is an energy-intensive process, where a significant cost involves the wet or dry-spinning of polyacrylonitrile (PAN) fiber precursors. Melt-spinning PAN fibers would allow for significant reduction in the production cost and production hazards. Ionic liquids (ILs) are an attractive fiber-processing medium because of their negligible vapor pressure and ...
DOI:
10.1021/acsami.9b19704

14. Efficient removal of iodide anion from aqueous solution with recyclable core-shell magnetic Fe3O4@Mg/Al layered double hydroxide (LDH)

Author:
Il-Kwon Jung; Yongheum Jo; Sol-Chan Han; Jong-Il Yun
Source:
Science of the total environment 2020 v.705 pp. 135814
ISSN:
0048-9697
Subject:
X-ray diffraction; adsorbents; adsorption; aluminum; anions; aqueous solutions; carbonates; coatings; economics; hydroxides; liquids; magnesium; magnetism; magnetite; physicochemical properties; remediation; surface area; transmission electron microscopy; zeta potential
Abstract:
... Magnetic Mg/Al layered double hydroxides (LDH) with three cationic ratios (Mg/Al = 2:1, 3:1, and 4:1) were successfully synthesized and utilized for the first time in an iodide adsorption study. The effects of the Mg/Al ratio of LDH on iodide adsorption were investigated, and physicochemical properties of synthetic LDHs depending on Mg/Al ratio were confirmed by XRD, TEM, ICP-OES, VSM, Zeta-potent ...
DOI:
10.1016/j.scitotenv.2019.135814

15. Efficient transformation of diethyl phthalate using calcium peroxide activated by pyrite

Author:
Yang Zhou; Min Huang; Xiaolei Wang; Juan Gao; Guodong Fang; Dongmei Zhou
Source:
Chemosphere 2020 v.253 pp. 126662
ISSN:
0045-6535
Subject:
X-ray diffraction; X-ray photoelectron spectroscopy; anions; aqueous solutions; bicarbonates; calcium peroxide; catalysts; catalytic activity; chlorides; diethyl phthalate; electron paramagnetic resonance spectroscopy; free radicals; hydrogen peroxide; hydroxyl radicals; iron; nitrates; pH; polluted soils; pyrite; scanning electron microscopy; soil remediation; sulfates; sulfur
Abstract:
... In this study, pyrite (FeS₂) was used as a novel activator of calcium peroxide (CaO₂) for the degradation of diethyl phthalate (DEP) in both aqueous solution and soil. DEP (10 mg/L) in aqueous solution was completely degraded within 5.0 min by the FeS₂ (0.30 g/L)/CaO₂ (1.0 mM) system at pH 3.5. X-ray diffraction (XRD), scanning electron microscopy (SEM), electron paramagnetic resonance (EPR), free ...
DOI:
10.1016/j.chemosphere.2020.126662

16. Embellishing bis-1,2,4-triazole with four nitroamino groups: advanced high-energy-density materials with remarkable performance and good stability

Author:
Qing Lang; Qi Sun; Qian Wang; Qiuhan Lin; Ming Lu
Source:
Journal of materials chemistry A 2020 v.8 no.23 pp. 11752-11760
ISSN:
2050-7496
Subject:
X-ray diffraction; anions; cations; hydrogen bonding; physicochemical properties; salts; triazoles
Abstract:
... Preparing high-energy-density materials (HEDMs) with performance comparable or superior to CL-20 has been at the forefront of energetic material research. In response to this challenge, four nitroamino groups were successfully introduced into a bis-1,2,4-triazole backbone to pursue the higher energetic performance. The neutral compound (NT-00) and high-energy salts, including the divalent (D1–D5) ...
DOI:
10.1039/d0ta03008b

17. Enhanced removal of dye from wastewater by Fenton process activated by core-shell NiCo2O4@FePc catalyst

Author:
Hengli Qian; Qidong Hou; Guanjie Yu; Yifan Nie; Chuanyunlong Bai; Xinyu Bai; Meiting Ju
Source:
Journal of cleaner production 2020 v.273 pp. 123028
ISSN:
0959-6526
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; X-ray photoelectron spectroscopy; adsorption; anions; bicarbonates; catalysts; catalytic activity; chlorides; cobalt; desorption; dyes; filtration; hydroxyl radicals; iron; liquids; mineralization; nickel; nitrogen; organic matter; oxygen; pollutants; reaction kinetics; superoxide anion; surface area; tap water; transmission electron microscopy; wastewater
Abstract:
... To achieve efficient degradation of dye in wastewater, the core-shell nickel cobalt spinel coated with iron phthalocyanine (NiCo₂O₄@FePc) catalyst was prepared via a facile template method and investigated as heterogenous catalyst for degradation of dye in Fenton process. The catalysts were systematically characterized by transmission electron microscopy (TEM), N₂ adsorption/desorption isotherms, ...
DOI:
10.1016/j.jclepro.2020.123028

18. Enhanced removal of vanadium(V) from groundwater by layered double hydroxide-supported nanoscale zerovalent iron

Author:
Xiangrui Kong; Jiehao Chen; Yunjia Tang; Yan Lv; Tan Chen; Hongtao Wang
Source:
Journal of hazardous materials 2020 v.392 pp. 122392
ISSN:
0304-3894
Subject:
X-ray diffraction; X-ray photoelectron spectroscopy; adsorption; anions; desorption; dissolved oxygen; groundwater; iron; pH; scanning electron microscopy; toxicity; vanadium
Abstract:
... To reduce the toxicity of vanadium(V) [V(V)] and inhibit the desorption of adsorbed vanadium in groundwater, we synthesized nanoscale zerovalent iron (nZVI) dispersed on layered double hydroxide (LDH) composites (nZVI@LDH) to remove V(V) from simulated groundwater. We found that nZVI@LDH could reduce high-valence vanadium to low-valence vanadium, then forming vanadium-containing precipitation to r ...
DOI:
10.1016/j.jhazmat.2020.122392

19. Green synthesis of iron nanoparticles using Korla fragrant pear peel extracts for the removal of aqueous Cr(VI)

Author:
Kun Rong; Jinye Wang; Zaiwang Zhang; Jiqiang Zhang
Source:
Ecological engineering 2020 v.149 pp. 105793
ISSN:
0925-8574
Subject:
Fourier transform infrared spectroscopy; Pyrus; X-ray diffraction; X-ray photoelectron spectroscopy; adsorption; anions; aqueous solutions; carbonates; chlorides; chromium; flavonoids; iron; kinetics; nanoparticles; nitrates; oxides; pH; pears; phosphates; polyphenols; scanning electron microscopy; sorption isotherms; sulfates; temperature; transmission electron microscopy
Abstract:
... Iron nanoparticles (KP-FeNPs) were successfully synthesized using Korla fragrant pear (Pyrus sinkiangensis Yu) peel extracts through a green synthetic method. The KP-FeNPs were characterized by TEM, SEM, XPS, XRD, and FTIR, and subsequently used to remove Cr(VI) from aqueous solutions. The KP-FeNPs were irregularly-shaped and ranged from 20 to 90 nm in size. Iron in the KP-FeNPs was mainly present ...
DOI:
10.1016/j.ecoleng.2020.105793

20. Highly Efficient Separation of Anionic Organic Pollutants from Water via Construction of Functional Cationic Metal–Organic Frameworks and Mechanistic Study

Author:
Chaofeng Zhao; Yao Du; Jichuan Zhang; Yongsheng Mi; Hui Su; Teng Fei; Shenghua Li; Siping Pang
Source:
ACS applied materials & interfaces 2020 v.12 no.20 pp. 22835-22844
ISSN:
1944-8252
Subject:
X-ray diffraction; activated carbon; adsorbents; adsorption; ambient temperature; anions; carbon nanotubes; coordination polymers; electrostatic interactions; energy; functional properties; heat; hydrogen bonding; ligands; nuclear magnetic resonance spectroscopy; oxygen; pollutants; pollution; sodium nitrate; sodium sulfate; titration; triazoles; wastewater
Abstract:
... Organic anions possess various functional properties; however, their presence in wastewater causes environmental pollution. Thus, coupling the separation of such species with the resultant function could be highly desirable. Herein, we propose a “killing two birds with one stone” strategy for highly efficient separation of organic pollutant anions from water at room temperature through direct cons ...
DOI:
10.1021/acsami.0c02624