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You searched for: Publication year rev 7981-2019 Remove constraint Publication year rev: 7981-2019 Subject term X-ray diffraction Remove constraint Subject term: X-ray diffraction
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1. (+)- and (−)-Alternarilactone A: Enantiomers with a Diepoxy-Cage-like Scaffold from an Endophytic Alternaria sp.

Author:
Jian-Wei Tang; Hou-Chao Xu; Wei-Guang Wang; Kun Hu; Yuan-Fei Zhou; Rong Chen; Xiao-Nian Li; Xue Du; Han-Dong Sun; Pema-Tenzin Puno
Source:
Journal of natural products 2019 v.82 no.4 pp. 735-740
ISSN:
1520-6025
Subject:
Alternaria; X-ray diffraction; enantiomers; endophytes; fungi; moieties; nuclear magnetic resonance spectroscopy; probability analysis; quantum mechanics; risk
Abstract:
... The enantiomers (+)- and (−)-alternarilactone A (1), the first examples of dibenzo-α-pyrones bearing a diepoxy-cage-like moiety, were isolated from the endophytic fungus Alternaria sp. hh930. The deficiency in ¹H–¹H COSY and HMBC correlations caused by the highly oxidized caged system of 1 and the deceptive and ambiguous signals such as “W” couplings in NMR data increased the risk of structure mis ...
DOI:
10.1021/acs.jnatprod.8b00571

2. (+)- and (−)-Preuisolactone A: A Pair of Caged Norsesquiterpenoidal Enantiomers with a Tricyclo[4.4.0¹,⁶.0²,⁸]decane Carbon Skeleton from the Endophytic Fungus Preussia isomera

Author:
Lu-Lin Xu; Hai-Li Chen; Ping Hai; Yuan Gao; Chuan-Dong Xie; Xiao-Long Yang; Ikuro Abe
Source:
Organic letters 2019 v.21 no.4 pp. 1078-1081
ISSN:
1523-7052
Subject:
Micrococcus luteus; Preussia; X-ray diffraction; antibacterial properties; biochemical pathways; carbon; chemical reactions; decane; enantiomers; endophytes; fungi; spectroscopy
Abstract:
... A pair of enantiomeric norsesquiterpenoids, (+)- and (−)-preuisolactone A (1) [(+)-1 and (−)-1)] featuring an unprecedented tricyclo[4.4.0¹,⁶.0²,⁸]decane carbon scaffold were isolated from Preussia isomera. Their structures were determined by spectroscopic and computed methods and X-ray crystallography. Compounds (+)-1 and (−)-1 are two rare naturally occurring sesquiterpenoidal enantiomers. A pla ...
DOI:
10.1021/acs.orglett.8b04123

3. (+/−)-Lucidumone, a COX-2 Inhibitory Caged Fungal Meroterpenoid from Ganoderma lucidum

Author:
Yong-Ming Yan; Hao-Xing Zhang; Huan Liu; Yan Wang; Jing-Bo Wu; Yan-Peng Li; Yong-Xian Cheng
Source:
Organic letters 2019 v.21 no.21 pp. 8523-8527
ISSN:
1523-7052
Subject:
Ganoderma lucidum; X-ray diffraction; amino acids; biochemical pathways; chemical reactions; chemical structure; meroterpenoids
Abstract:
... (±)-Lucidumone (1), an enantiomeric meroterpenoid possessing an unprecedented skeleton comprising a fused 6/5/6/6/5 polycyclic system, was isolated from Ganoderma lucidum and structurally identified. The absolute configuration of (−)-1 was assigned by single-crystal X-ray crystallography. A plausible biosynthetic pathway for 1 is proposed. A chemical biology approach reveals that (−)-1 selectively ...
DOI:
10.1021/acs.orglett.9b02840

4. (±)-Alternamgin, a Pair of Enantiomeric Polyketides, from the Endophytic Fungi Alternaria sp. MG1

Author:
Jun-Chen Wu; Yanan Hou; Qianhe Xu; Xiao-Jie Jin; Yaxiong Chen; Jianguo Fang; Burong Hu; Quan-Xiang Wu
Source:
Organic letters 2019 v.21 no.5 pp. 1551-1554
ISSN:
1523-7052
Subject:
Alternaria; X-ray diffraction; biochemical pathways; chemical reactions; chemical structure; endophytes; fungi; human cell lines; necrosis; polyketides
Abstract:
... A pair of enantiomeric polyketides, (+)- and (−)-alternamgin (1), featuring an unprecedented 6/6/6/6/5/6/6 seven ring backbone, were isolated from the endophytic fungi Alternaria sp. MG1. The relative configuration of 1 was determined using X-ray diffraction, and the absolute configurations of (±)-1 were confirmed by comparing the experimental and calculated ECD data. Plausible biosynthetic pathwa ...
DOI:
10.1021/acs.orglett.9b00475

5. La₁ .₅Sr₀.₅NiMn₀.₅Ru₀.₅O₆ Double Perovskite with Enhanced ORR/OER Bifunctional Catalytic Activity

Author:
Maria Retuerto; Federico Calle-Vallejo; Laura Pascual; Gunnar Lumbeeck; María Teresa Fernandez-Diaz; Mark Croft; Jagannatha Gopalakrishnan; Miguel A. Peña; Joke Hadermann; Martha Greenblatt; Sergio Rojas
Source:
ACS applied materials & interfaces 2019 v.11 no.24 pp. 21454-21464
ISSN:
1944-8252
Subject:
X-ray absorption spectroscopy; X-ray diffraction; catalysts; catalytic activity; cations; density functional theory; electrochemistry; manganese; neutron diffraction; oxidation; oxygen; oxygen production; transmission electron microscopy
Abstract:
... Perovskites (ABO₃) with transition metals in active B sites are considered alternative catalysts for the water oxidation to oxygen through the oxygen evolution reaction (OER) and for the oxygen reduction through the oxygen reduction reaction (ORR) back to water. We have synthesized a double perovskite (A₂BB′O₆) with different cations in A, B, and B′ sites, namely, (La₁.₅Sr₀.₅)A(Ni₀.₅Mn₀.₅)B(Ni₀.₅R ...
DOI:
10.1021/acsami.9b02077

6. 1-Aminopyridinium Ylides as Monodentate Directing Groups for sp³ C–H Bond Functionalization

Author:
Ky Khac Anh Le; Hanh Nguyen; Olafs Daugulis
Source:
Journal of the American Chemical Society 2019 v.141 no.37 pp. 14728-14735
ISSN:
1520-5126
Subject:
X-ray diffraction; alkylation; aminoquinolines; arylation; carbon-hydrogen bond activation; carboxylic acids; catalytic activity; chemical bonding; ligands; moieties; palladium; pyridines
Abstract:
... 1-Aminopyridinium ylides are efficient directing groups for palladium-catalyzed β-arylation and alkylation of sp³ C–H bonds in carboxylic acid derivatives. The efficiency of these directing groups depends on the substitution at the pyridine moiety. The unsubstituted pyridine-derived ylides allow functionalization of primary C–H bonds, while methylene groups are unreactive in the absence of externa ...
DOI:
10.1021/jacs.9b06643
PubMed:
31529954
PubMed Central:
PMC6880753

7. 110th Anniversary: Dry Reforming of Methane over Ni- and Sr-Substituted Lanthanum Zirconate Pyrochlore Catalysts: Effect of Ni Loading

Author:
Srikar Bhattar; Aiswarya Krishnakumar; Swarom Kanitkar; Ashraf Abedin; Dushyant Shekhawat; Daniel J. Haynes; James J. Spivey
Source:
Industrial & engineering chemistry process design and development 2019 v.58 no.42 pp. 19386-19396
ISSN:
1520-5045
Subject:
X-ray diffraction; carbon; catalysts; lanthanum; methane; nickel; nickel oxide; process design; streams; thermal stability; zirconium
Abstract:
... Pyrochlores are thermally stable materials that can be doped with a metal to produce active catalyst for dry reforming of methane (DRM). La₁.₉₅Sr₀.₀₅Zr₁.₉₀₄Ni₀.₀₉₆O₇–d (LSNZ1) and La₁.₉₅Sr₀.₀₅Zr₁.₄₄Ni₀.₅₆O₇–d (LSNZ6), with 1 and 6 wt % Ni loading at Zr site, respectively, were investigated for DRM. XRD of fresh catalysts confirmed the formation of pyrochlore structure. Also, the presence of the La ...
DOI:
10.1021/acs.iecr.9b02434

8. 2-Iodoxybenzoic acid ditriflate: the most powerful hypervalent iodine(v) oxidant

Author:
Mekhman S. Yusubov; Natalia S. Soldatova; Pavel S. Postnikov; Rashid R. Valiev; Akira Yoshimura; Thomas Wirth; Victor N. Nemykin; Viktor V. Zhdankin
Source:
Chemical communications 2019 v.55 no.54 pp. 7760-7763
ISSN:
1364-548X
Subject:
X-ray diffraction; hydrocarbons; iodine; oxidants; oxidation
Abstract:
... A ditriflate derivative of 2-iodoxybenzoic acid (IBX) was prepared by the reaction of IBX with trifluoromethanesulfonic acid and characterized by single crystal X-ray crystallography. IBX-ditriflate is the most powerful oxidant in a series of structurally similar IBX derivatives which is best illustrated by its ability to readily oxidize hydrocarbons and the oxidation resistant polyfluoroalcohols. ...
DOI:
10.1039/c9cc04203b

9. 2D BiVO4/g-C3N4 Z-scheme photocatalyst for enhanced overall water splitting

Author:
Hanyi Xie; Yanfang Zhao; Huijuan Li; Yizhen Xu; Xiangfeng Chen
Source:
Journal of materials science 2019 v.54 no.15 pp. 10836-10845
ISSN:
0022-2461
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; X-ray photoelectron spectroscopy; electron paramagnetic resonance spectroscopy; graphene; hydrogen production; irradiation; optical properties; oxygen production; pH; photocatalysis; photocatalysts; photoluminescence; scanning electron microscopes; semiconductors; transmission electron microscopes; ultraviolet-visible spectroscopy
Abstract:
... A 2D Z-scheme BiVO₄/g-C₃N₄ photocatalyst was successfully synthesized by a two-step hydrothermal/calcination method for overall water splitting. Morphology design to restrain the growth of BiVO₄ nanoplates with thickness around 20 nm was achieved by adjusting the pH value and introducing graphene sheets. Then, the BiVO₄/g-C₃N₄ (BVO-CN) hybrid photocatalysts were fabricated with different mass rati ...
DOI:
10.1007/s10853-019-03664-9

10. 2D few-layer iron phosphosulfide: a self-buffer heterophase structure induced by irreversible breakage of P–S bonds for high-performance lithium/sodium storage

Author:
Chao-Ying Fan; Xiao-Hua Zhang; Yan-Hong Shi; Hai-Yang Xu; Jing-Ping Zhang; Xing-Long Wu
Source:
Journal of materials chemistry A 2019 v.7 no.4 pp. 1529-1538
ISSN:
2050-7496
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; anodes; chemical bonding; electrochemistry; energy; graphene; iron; lithium; nanosheets; phosphides; phosphorus; sodium; transmission electron microscopy
Abstract:
... To pursue an anode candidate with a high capacity and favorable potential is urgent for a prospective energy storage system. In this work, an earth-abundant ternary metal phosphosulfide, here FePS₃, which is expected to combine the merits of metal sulfide and phosphorus, is explored for lithium/sodium storage. In order to facilitate charge transfer and relieve volume stress on the electrode, orien ...
DOI:
10.1039/c8ta09057b

11. 2D-2D growth of NiFe LDH nanoflakes on montmorillonite for cationic and anionic dye adsorption performance

Author:
De Bin Jiang; Chuan Jing; Yunsong Yuan; Li Feng; Xiaoying Liu; Fan Dong; Biqing Dong; Yu Xin Zhang
Source:
Journal of colloid and interface science 2019 v.540 pp. 398-409
ISSN:
0021-9797
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; X-ray photoelectron spectroscopy; adsorbents; adsorption; differential thermal analysis; hot water treatment; hydroxides; methyl orange; methylene blue; models; montmorillonite; scanning electron microscopy; surface area; thermogravimetry; wastewater
Abstract:
... NiFe layered double hydroxides nanoflakes decorated montmorillonite (MMT@NiFe LDH) was successfully prepared by a one-pot hydrothermal method. The 2D-2D growth MMT@NiFe LDH was utilized as an effective adsorbent for removal of anionic dye of methyl orange (MO) and cationic dye of methylene blue (MB). The mole ratio of Ni2+/Fe3+ could quite influence the interlayer spacing, surface area per unit ch ...
DOI:
10.1016/j.jcis.2019.01.022

12. 2D-Coordination polymer containing lead(II) in a hemidirected PbO₄S₃ environment formed by molecular breaking of the 1,3-oxathiolane ligand

Author:
Zahra Mardani; Samira Akbari; Keyvan Moeini; Majid Darroudi; Cameron Carpenter-Warren; Alexandra M. Z. Slawin; J. Derek Woollins
Source:
Zeitschrift für Naturforschung 2019 v.74 no.7-8 pp. 547-551
ISSN:
1865-7117
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; beta-mercaptoethanol; geometry; hydrogen bonding; lead; ligands; nuclear magnetic resonance spectroscopy; polymers; pyridines; thiols
Abstract:
... A new 1,3-oxathiolane-based ligand, 2-(1,3-oxathiolan-2-yl)pyridine, was prepared and its coordination to lead(II) was investigated. Experiments revealed a ligand-breaking reaction during the complexation process, which leads to the formation of a 2D-coordination polymer of lead(II), [Pb(μ³-HME)(μ-OAc)]ₙ; H₂ME: 2-mercaptoethanol. The compounds have been characterized by elemental analysis, FT-IR, ...
DOI:
10.1515/znb-2019-0043

13. 2D–3D Mixed Organic–Inorganic Perovskite Layers for Solar Cells with Enhanced Efficiency and Stability Induced by n-Propylammonium Iodide Additives

Author:
Disheng Yao; Chunmei Zhang; Shengli Zhang; Yang Yang; Aijun Du; Eric Waclawik; Xiaochen Yu; Gregory J. Wilson; Hongxia Wang
Source:
ACS applied materials & interfaces 2019 v.11 no.33 pp. 29753-29764
ISSN:
1944-8252
Subject:
X-ray diffraction; X-ray photoelectron spectroscopy; additives; air; cations; contact angle; density functional theory; encapsulation; energy; hydrophobicity; hysteresis; industrial applications; oxygen; relative humidity; solar cells; solar energy; surface water; wettability
Abstract:
... Device instability has become an obstacle for the industrial application of organic–inorganic metal halide perovskite solar cells that has already demonstrated over 23% laboratory power conversion efficiency (PCE). It has been discovered that the sliding of A-site cations in the perovskite compound through and out of the three-dimensional [PbI₆]⁴– crystal frame is one of the main reasons that are ...
DOI:
10.1021/acsami.9b06305

14. 3-Substituted Benzo[e][1,2,4]triazines: Synthesis and Electronic Effects of the C(3) Substituent

Author:
Agnieszka Bodzioch; Dominika Pomikło; Małgorzata Celeda; Anna Pietrzak; Piotr Kaszyński
Source:
Journal of organic chemistry 2019 v.84 no.10 pp. 6377-6394
ISSN:
1520-6904
Subject:
Lewis bases; X-ray diffraction; carboxylic acids; catalytic activity; copper; crystal structure; density functional theory; energy; geometry; hydrolysis; morpholine; nitroanilines; nuclear magnetic resonance spectroscopy; organic chemistry; palladium; triazines; ultraviolet-visible spectroscopy
Abstract:
... A series of 19 structurally diverse C(3)-substituted derivatives of benzo[e][1,2,4]triazine were synthesized from 3-chloro- (1c) and 3-iodobenzo[e][1,2,4]triazine (1d) obtained in three steps from 2-nitroaniline in 37–55% yields. Nucleophilic aromatic substitution and metal-catalyzed (Pd, Cu) reactions led to functional derivatives that include alkyl (C₅H₁₁), (het)aryl (Ph, 2-thienyl, ferrocenyl), ...
DOI:
10.1021/acs.joc.9b00716

15. 3D energy frameworks of dimethylbenzophenone tetramorphs

Author:
S. Madan Kumar
Source:
Heliyon 2019 v.5 no.2 pp. e01209
ISSN:
2405-8440
Subject:
X-ray diffraction; chemical interactions; crystal structure; crystallization; energy
Abstract:
... The tetramorphᵗʰ crystals of 4,4–dimethylbenzophenone (D) were obtained using slow-evaporation crystallization method and the structure is elucidated using single crystal X-ray diffraction technique. D crystallizes in the orthorhombic crystal system (space group Pbca) with cell parameters a = 14.6986 (11) Å, b = 6.1323 (4) Å, c = 26.2730 (18) Å, V = 2368.2 (3) ų and Z = 8. In the crystal structur ...
DOI:
10.1016/j.heliyon.2019.e01209
PubMed:
30839935
PubMed Central:
PMC6365486

16. A 3D free-standing lithiophilic silver nanowire aerogel for lithium metal batteries without lithium dendrites and volume expansion: in operando X-ray diffraction

Author:
Nutthaphon Phattharasupakun; Juthaporn Wutthiprom; Salatan Duangdangchote; Montree Sawangphruk
Source:
Chemical communications 2019 v.55 no.40 pp. 5689-5692
ISSN:
1364-548X
Subject:
X-ray diffraction; aerogels; anodes; cathodes; chemical reactions; dendrites; iron phosphates; lithium; lithium batteries; nanosilver; nanowires; phase transition; silver
Abstract:
... A 3D free-standing lithiophilic silver nanowire aerogel (AgNWA) can stop the dendritic growth of lithium metal at the initial nucleation process. The 3D structure can also suppress the infinite volume expansion of lithium during cycling. The active AgNWA scaffold can serve as a Li reservoir to compensate for the irreversible consumption of Li. The lithiated AgNWA anode was coupled with a lithium i ...
DOI:
10.1039/c9cc01528k

17. 3D gel printing of graded TiC-high manganese steel cermet

Author:
Xinyue Zhang; Leichen Guo; Fang Yang; Alex A. Volinsky; Megan Hostetter; Zhimeng Guo
Source:
Journal of materials science 2019 v.54 no.3 pp. 2122-2132
ISSN:
0022-2461
Subject:
X-ray diffraction; gels; hardness; manganese; manufacturing; mechanical properties; microstructure; polymerization; rheological properties; scanning electron microscopy; slurries; steel
Abstract:
... A new solid freeform process, 3D gel printing (3DGP), was proposed for designing and manufacturing graded composites. As an example, TiC-high manganese steel cermet with a gradient distribution of TiC was successfully designed and fabricated by 3DGP. The rheological behavior and polymerization of slurries with different TiC content have been researched. The complex-shaped green bodies were printed ...
DOI:
10.1007/s10853-018-2945-5

18. 3D structure fungi-derived carbon stabilized stearic acid as a composite phase change material for thermal energy storage

Author:
Chuanchang Li; Baoshan Xie; Zhangxing He; Jian Chen; Yi Long
Source:
Renewable energy 2019 v.140 pp. 862-873
ISSN:
0960-1481
Subject:
Fourier transform infrared spectroscopy; Raman spectroscopy; X-ray diffraction; X-ray photoelectron spectroscopy; carbon; carbonization; enthalpy; freezing; melting; moieties; renewable energy sources; stearic acid; surface area; thermal conductivity; thermal energy; thermal stability
Abstract:
... Stearic acid (SA)/fungi-derived carbon (FDC) composite phase change materials (PCM) were fabricated by vacuum impregnation, where three types of FDC (FDC-C, FDC-H, and FDC-K) as carrier were synthesized by diverse synthetic procedures of carbonization. The FDC-K modified by synergistic hydrothermal and KOH-assisted calcination process had a 3D-cellular structure with considerably higher inner surf ...
DOI:
10.1016/j.renene.2019.03.121

19. 3α,19-Dihydroxyl-ent-pimara-8(14),15-diene, a new diterpenoid from the rhizomes of Ricinus communis

Author:
Sheng-Nan Zhang; Jin Zeng; Ya-Nan Tan; Rui-Jing Ma; Gui-Jie Zhang; Heng-Shan Wang; Qin-Gang Tan
Source:
Journal of Asian natural products research 2019 v.21 no.6 pp. 522-527
ISSN:
1477-2213
Subject:
Ricinus communis; X-ray diffraction; diterpenoids; protein-tyrosine-phosphatase; rhizomes; spectroscopy
Abstract:
... A new natural product, 3α,19-dihydroxyl-ent-pimara-8(14),15-diene (1), which possesses an α-orientation hydroxymethyl at C-4 and ∆⁸,¹⁴ groups, as well as eight known compounds, was isolated from the rhizomes of Ricinus communis. The structure of 1 was elucidated by extensive spectroscopic methods and its absolute configurations were confirmed by X-ray crystallographic analysis. The inhibitory rate ...
DOI:
10.1080/10286020.2018.1461087

20. 4′-Aminobenzo-18-crown-6 functionalized magnetic nanoparticles as a solid-phase extraction adsorbent for the determination of Pb²⁺

Author:
Jing-yan Kang; Wei Ha; Hai-xia Zhang; Yan-ping Shi
Source:
Analytical methods 2019 v.11 no.13 pp. 1735-1742
ISSN:
1759-9679
Subject:
Fourier transform infrared spectroscopy; X-ray diffraction; adsorbents; adsorption; apples; detection limit; iron oxides; lead; light scattering; magnetism; metal ions; milk; nanoparticles; rice; solid phase extraction; tap water; transmission electron microscopy; zeta potential
Abstract:
... A novel magnetic adsorbent has been designed and fabricated for the adsorption and determination of lead metal ions (Pb²⁺) based on a self-assembly approach between 4′-aminobenzo-18-crown-6 (AB18C6) and Fe₃O₄–CHO via dehydration condensation. 4′-Aminobenzo-18-crown-6 modified Fe₃O₄ (Fe₃O₄@AB18C6) was characterized by transmission electron microscopy (TEM), dynamic light scattering (DLS), Fourier t ...
DOI:
10.1039/c8ay02760a