<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Amoureux, J. P.</style></author><author><style face="normal" font="default" size="100%">Delevoye, L.</style></author><author><style face="normal" font="default" size="100%">Steuernagel, S.</style></author><author><style face="normal" font="default" size="100%">Gan, Zhengting</style></author><author><style face="normal" font="default" size="100%">Ganapathy, Subramanian</style></author><author><style face="normal" font="default" size="100%">Montagne, L.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Increasing the sensitivity of 2D high-resolution NMR methods applied to quadrupolar nuclei</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Magnetic Resonance</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">high-resolution</style></keyword><keyword><style  face="normal" font="default" size="100%">quadrupolar nuclei</style></keyword><keyword><style  face="normal" font="default" size="100%">sensitivity</style></keyword><keyword><style  face="normal" font="default" size="100%">Solid-state NMR</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2005</style></year><pub-dates><date><style  face="normal" font="default" size="100%">FEB</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">2</style></number><publisher><style face="normal" font="default" size="100%">ACADEMIC PRESS INC ELSEVIER SCIENCE</style></publisher><pub-location><style face="normal" font="default" size="100%">525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA</style></pub-location><volume><style face="normal" font="default" size="100%">172</style></volume><pages><style face="normal" font="default" size="100%">268-278</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Gan and Kwak recently proposed a soft-pulse added mixing (SPAM) idea in the classical two-pulse multiple-quantum magic-angle spinning scheme. In the SPAM method, a soft pi/2 pulse is added after the second hard-pulse (conversion pulse) and all coherence orders in between them are constructively used to obtain the signal. We, here, further extend this idea to distributed samples where the signal mainly results from echo pathways and that from anti-echo pathways dies Out after a few t(1) increments. We show that, with a combination of SPAM and collection of fewer anti-echoes, an enhancement of the signal to noise ratio by a factor of ca. 3 may be obtained over the z-filtered version. This may prove to be useful even for samples with long T'(2) relaxation times. (C) 2004 Elsevier Inc. All rights reserved.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">&lt;p&gt;Foreign&lt;/p&gt;</style></custom3><custom4><style face="normal" font="default" size="100%">2.889</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Maity, Niladri</style></author><author><style face="normal" font="default" size="100%">Basu, Susmit</style></author><author><style face="normal" font="default" size="100%">Mapa, Maitri</style></author><author><style face="normal" font="default" size="100%">Rajamohanan, Pattuparambil R.</style></author><author><style face="normal" font="default" size="100%">Ganapathy, Subramanian</style></author><author><style face="normal" font="default" size="100%">Gopinath, Chinnakonda S.</style></author><author><style face="normal" font="default" size="100%">Bhaduri, Sumit</style></author><author><style face="normal" font="default" size="100%">Lahiri, Goutam Kumar</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Effect of spacer groups on the performance of MCM-41-supported platinum cluster-derived hydrogenation catalysts</style></title><secondary-title><style face="normal" font="default" size="100%">Journal of Catalysis</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">functionalized inorganic oxides</style></keyword><keyword><style  face="normal" font="default" size="100%">hydrogenation catalysts</style></keyword><keyword><style  face="normal" font="default" size="100%">MCM-41</style></keyword><keyword><style  face="normal" font="default" size="100%">platinum carbonyl cluster</style></keyword><keyword><style  face="normal" font="default" size="100%">Solid-state NMR</style></keyword><keyword><style  face="normal" font="default" size="100%">spacer groups</style></keyword><keyword><style  face="normal" font="default" size="100%">XPS</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2006</style></year><pub-dates><date><style  face="normal" font="default" size="100%">SEP</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">2</style></number><publisher><style face="normal" font="default" size="100%">ACADEMIC PRESS INC ELSEVIER SCIENCE</style></publisher><pub-location><style face="normal" font="default" size="100%">525 B ST, STE 1900, SAN DIEGO, CA 92101-4495 USA</style></pub-location><volume><style face="normal" font="default" size="100%">242</style></volume><pages><style face="normal" font="default" size="100%">332-339</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;MCM-41 was functionalized with (EtO)(3)SiCH2Cl, (MeO)(3)SiCH2CH2CH2Cl, and (CH3)Cl2SiCH2Cl. The functionalized materials were characterized by solid-state NMR (CPMAS, Si-29 and C-13) and XPS. The NMR data indicate that three new silicon environments were created by(EtO)(3)SiCH2Cl and (MeO)(3)SiCH2CH2CH2Cl, whereas with (CH3)Cl2SiCH2Cl, two new silicon environments were obtained. XPS results from Si 2p core level and the valence band from the material functionalized by (MeO)(3)Si(CH2)(3)Cl was found to be the same as that of the corresponding fresh catalyst (1a), in contrast to that of the materials functionalized by the other two silane reagents. After further functionalization with triethylamine, these materials were used as inorganic anion exchangers to support the cluster anion [Pt-12(CO)(24)](2-). Solid-state NMR (29Si, C-13, N-15) was used to establish the presence of the quaternary ammonium group in the cluster-supported species. Analogous materials were also created using fumed silica as the support, and all of the cluster-supported materials were tested as catalysts for the hydrogenation of methyl pyruvate, acetophenone, nitrobenzene, benzonitrile, ethylacetoacetate, 4-nitrotoluene, cyclohexanone, allyl alcohol, and styrene. The best activity was obtained for the catalyst that had MCM-41 as the support and chloropropyl as the spacer group. TEM showed that the supports and the spacer groups had observable effects on the platinum crystallite size of the catalysts. (c) 2006 Elsevier Inc. All rights reserved.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">&lt;p&gt;Foreign&lt;/p&gt;</style></custom3><custom4><style face="normal" font="default" size="100%">7.354</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Ganapathy, Subramanian</style></author><author><style face="normal" font="default" size="100%">Delevoye, L.</style></author><author><style face="normal" font="default" size="100%">Arnoureux, J. P.</style></author><author><style face="normal" font="default" size="100%">Madhu, Perunthiruthy K.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Heteronuclear dipolar decoupling effects on multiple-quantum and satellite-transition magic-angle spinning NMR spectra</style></title><secondary-title><style face="normal" font="default" size="100%">Magnetic Resonance in Chemistry</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">heteronuclear broadening</style></keyword><keyword><style  face="normal" font="default" size="100%">heteronuclear decoupling</style></keyword><keyword><style  face="normal" font="default" size="100%">homogeneous broadening</style></keyword><keyword><style  face="normal" font="default" size="100%">MQMAS</style></keyword><keyword><style  face="normal" font="default" size="100%">quadrupolar nuclei</style></keyword><keyword><style  face="normal" font="default" size="100%">Solid-state NMR</style></keyword><keyword><style  face="normal" font="default" size="100%">STMAS</style></keyword><keyword><style  face="normal" font="default" size="100%">TPPM</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2008</style></year><pub-dates><date><style  face="normal" font="default" size="100%">OCT</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">10</style></number><publisher><style face="normal" font="default" size="100%">JOHN WILEY &amp; SONS LTD</style></publisher><pub-location><style face="normal" font="default" size="100%">THE ATRIUM, SOUTHERN GATE, CHICHESTER PO19 8SQ, W SUSSEX, ENGLAND</style></pub-location><volume><style face="normal" font="default" size="100%">46</style></volume><pages><style face="normal" font="default" size="100%">948-954</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;We here report on the influence of heteronuclear dipolar decoupling on the Al-27 3QMAS, 5QMAS, and the double-quantum filter-satellite-transition magic-angle spinning (DQF-STMAS) spectra of a strongly dipolar-coupled system, gibbsite. The requirements for heteronuclear dipolar decoupling increase with the order of coherence evolving in the indirect dimension of a two-dimensional (2D) experiment. The isotropic line width of the high-resolution 2D spectra, in samples like gibbsite, is composed of four parts: the distribution of isotropic shifts (delta(ISO), delta(QIS)), the homogeneous broadening related to the proton-proton flip-flop terms, the Al-27-Al-27 homonulcear dipolar couplings, and the H-1-Al-27 heteronuclear dipolar couplings. It is shown that, even in the case of gibbsite, where a strong proton-proton bath exists, the main resolution limiting factor in these experiments resides in the H-1-Al-27 dipolar interaction. Copyright (C) 2008 John Wiley &amp;amp; Sons, Ltd.&lt;/p&gt;</style></abstract><issue><style face="normal" font="default" size="100%">10</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">1.226</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Chandrakesan, Muralidharan</style></author><author><style face="normal" font="default" size="100%">Sarkar, Bidyut</style></author><author><style face="normal" font="default" size="100%">Mithu, Venus Singh</style></author><author><style face="normal" font="default" size="100%">Rajiv M. Abhyankar</style></author><author><style face="normal" font="default" size="100%">Bhowmik, Debanjan</style></author><author><style face="normal" font="default" size="100%">Nag, Suman</style></author><author><style face="normal" font="default" size="100%">Sahoo, Bankanidhi</style></author><author><style face="normal" font="default" size="100%">Shah, Riddhi</style></author><author><style face="normal" font="default" size="100%">Gurav, Sushma</style></author><author><style face="normal" font="default" size="100%">Banerjee, Raja</style></author><author><style face="normal" font="default" size="100%">Dandekar, Sucheta</style></author><author><style face="normal" font="default" size="100%">Jose, Jaya C.</style></author><author><style face="normal" font="default" size="100%">Sengupta, Neelanjana</style></author><author><style face="normal" font="default" size="100%">Madhu, Perunthiruthy K.</style></author><author><style face="normal" font="default" size="100%">Maiti, Sudipta</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Basic structural motif and major biophysical properties of Amyloid-beta are encoded in the fragment 18-35</style></title><secondary-title><style face="normal" font="default" size="100%">Chemical Physics</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Alzheimer's disease</style></keyword><keyword><style  face="normal" font="default" size="100%">Fluorescence correlation spectroscopy</style></keyword><keyword><style  face="normal" font="default" size="100%">Protein aggregation</style></keyword><keyword><style  face="normal" font="default" size="100%">Solid-state NMR</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2013</style></year><pub-dates><date><style  face="normal" font="default" size="100%">AUG</style></date></pub-dates></dates><number><style face="normal" font="default" size="100%">SI</style></number><publisher><style face="normal" font="default" size="100%">ELSEVIER SCIENCE BV</style></publisher><pub-location><style face="normal" font="default" size="100%">PO BOX 211, 1000 AE AMSTERDAM, NETHERLANDS</style></pub-location><volume><style face="normal" font="default" size="100%">422</style></volume><pages><style face="normal" font="default" size="100%">80-87</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;Aggregation and misfolding of the amyloid beta (A beta) peptide is thought to initiate Alzheimer's disease (AD). Here we study the role played by its central segment (A beta(18-35)) in determining these properties. A beta(18-35) has a solubility of 18 mu M. The soluble fraction consists mainly of small oligomers, which have mixed beta-sheet and random coil structures. The monomer is mostly a random coil with some residual compactness. Aggregated A beta(18-35) forms fibrils of width 3.0 +/- 0.7 nm, which is consistent with a hairpin shape. Each of these properties has a close similarity to A beta(40). Remarkably, solid state NMR indicates that the fibrils also retain the secondary structure and tertiary contacts of A beta(40). This is the shortest fragment of A beta reported so far which preserves its fibrillar architecture, including the hairpin turn, as well as its solution phase conformational properties. Residues 18-35 should therefore be a key target of AD therapeutics. (C) 2013 Published by Elsevier B. V.&lt;/p&gt;</style></abstract><custom3><style face="normal" font="default" size="100%">Foreign</style></custom3><custom4><style face="normal" font="default" size="100%">2.028
</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Rawool, Sushma A.</style></author><author><style face="normal" font="default" size="100%">Samanta, Anupam</style></author><author><style face="normal" font="default" size="100%">Ajithkumar, T. G.</style></author><author><style face="normal" font="default" size="100%">Kar, Yusuf</style></author><author><style face="normal" font="default" size="100%">Polshettiwar, Vivek</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Photocatalytic hydrogen generation and CO2 conversion using g-C3N4 decorated dendritic fibrous nanosilica: role of interfaces between silica and g-C3N4</style></title><secondary-title><style face="normal" font="default" size="100%">ACS Applied Energy Materials</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">CO2 conversion</style></keyword><keyword><style  face="normal" font="default" size="100%">DFNS</style></keyword><keyword><style  face="normal" font="default" size="100%">g-C3N4</style></keyword><keyword><style  face="normal" font="default" size="100%">Hydrogen generation</style></keyword><keyword><style  face="normal" font="default" size="100%">nanocatalysts</style></keyword><keyword><style  face="normal" font="default" size="100%">photocatalysts</style></keyword><keyword><style  face="normal" font="default" size="100%">Solid-state NMR</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2020</style></year><pub-dates><date><style  face="normal" font="default" size="100%">SEP </style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">3</style></volume><pages><style face="normal" font="default" size="100%">8150-8158</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;We have synthesized g-C3N4 decorated over dendritic fibrous nanosilica (DFNS). The generation of C-N-Si interfaces by coating each fiber of DFNS with g-C3N4 not only provided high surface area but also affected the optical and electronic properties of the composite. The catalyst synthesis reproducibility issue of g-C3N4 was resolved using a vacuum-sealed quartz tube. The extended light absorption in the visible region, enhanced lifetime of photogenerated charge carriers due to the formation of interfaces between silica and g-C3N4 (confirmed by solid-state NMR), and increased surface area result in the improved photocatalytic activity of DFNS/g-C(3)N(4)for hydrogen generation and CO2 conversion.&lt;/p&gt;
</style></abstract><issue><style face="normal" font="default" size="100%">9</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">&lt;p&gt;Foreign&lt;/p&gt;
</style></custom3><custom4><style face="normal" font="default" size="100%">&lt;p&gt;4.473&lt;/p&gt;
</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hareendran, Chaithanya</style></author><author><style face="normal" font="default" size="100%">Alsirawan, Bashir</style></author><author><style face="normal" font="default" size="100%">Paradkar, Anant</style></author><author><style face="normal" font="default" size="100%">Ajithkumar, T. G.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">In situ monitoring of competitive coformer exchange reaction by 1H MAS solid-state NMR</style></title><secondary-title><style face="normal" font="default" size="100%">Molecualr Pharmaceutics</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">caffeine cocrystal</style></keyword><keyword><style  face="normal" font="default" size="100%">coformer exchange reaction</style></keyword><keyword><style  face="normal" font="default" size="100%">in situ monitoring</style></keyword><keyword><style  face="normal" font="default" size="100%">polymorphism</style></keyword><keyword><style  face="normal" font="default" size="100%">Solid-state NMR</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2024</style></year><pub-dates><date><style  face="normal" font="default" size="100%">FEB </style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">21</style></volume><pages><style face="normal" font="default" size="100%">1479-1489</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;
	In a competitive coformer exchange reaction, a recent topic of interest in pharmaceutical research, the coformer in a pharmaceutical cocrystal is exchanged with another coformer that is expected to form a cocrystal that is more stable. There will be a competition between coformers to form the most stable product through the formation of hydrogen bonds. This will cause destabilization of the pharmaceutical products during processing or storage. Therefore, it is important to develop a mechanistic understanding of this transformation by monitoring each and every step of the reaction, employing a technique such as H-1 nuclear magnetic resonance (NMR). In this study, an in situ monitoring of a coformer exchange reaction is carried out by H-1 magic angle spinning (MAS) solid-state NMR (SSNMR) at a spinning frequency of 60 kHz. The changes in caffeine maleic acid cocrystals on addition of glutaric acid and caffeine glutaric cocrystals on addition of maleic acid were monitored. In all of the reactions, it has been observed that caffeine glutaric acid Form I is formed. When glutaric acid was added to 2:1 caffeine maleic acid, the formation of metastable 1:1 caffeine glutaric acid Form I was observed at the start of the experiment, indicating that the centrifugal pressure is enough for the formation. The difference in the end product of the reactions with a similar reaction pathway of 1:1 and 2:1 reactant stoichiometry indicates that a complete replacement of maleic acid has occurred only in the 1:1 stoichiometry of the reactants. The polymorphic transition of caffeine glutaric acid Form II to Form I at higher temperatures was a crucial reason that triggered the exchange of glutaric acid with maleic acid in the reaction of caffeine glutaric acid and maleic acid. Our results are novel since the new reaction pathways in competitive coformer exchange reactions enabled understanding the remarkable role of stoichiometry, polymorphism, temperature, and centrifugal pressure.&lt;/p&gt;
</style></abstract><issue><style face="normal" font="default" size="100%">3</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">&lt;p&gt;
	Foreign&lt;/p&gt;
</style></custom3><custom4><style face="normal" font="default" size="100%">&lt;p&gt;
	4.9&lt;/p&gt;
</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Hareendran, Chaithanya</style></author><author><style face="normal" font="default" size="100%">Ajithkumar, T. G.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Probing the effect of fluorine on hydrogen bonding interactions in a pharmaceutical hydrate using Advanced Solid-State NMR</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular Pharmaceutics</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">DQSQ</style></keyword><keyword><style  face="normal" font="default" size="100%">Hydrogenbonding</style></keyword><keyword><style  face="normal" font="default" size="100%">pharmaceutical hydrate</style></keyword><keyword><style  face="normal" font="default" size="100%">regorafenib</style></keyword><keyword><style  face="normal" font="default" size="100%">Solid-state NMR</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2025</style></year><pub-dates><date><style  face="normal" font="default" size="100%">MAR </style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">22</style></volume><pages><style face="normal" font="default" size="100%">1869-1880</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;
	Structural studies of pharmaceutical hydrates are essential to understanding stability-related issues, especially during the heating process of formulation. A thorough understanding of the hydration and dehydration behavior of active pharmaceutical ingredient (API) hydrate is also important since phase transitions can occur during the formulation process. This is because dehydration could result in a considerable rearrangement in the structure if water-API hydrogen bonding is present. We perform advanced solid-state NMR experiments on regorafenib monohydrate to investigate the role of fluorine in hydrogen bonding interaction, and the results are compared to its anhydrous form and its structural analogue, namely, sorafenib. Our results show that significant structural changes could not be observed on dehydration. Based on our study, it can be concluded that the introduction of fluorine restricts the intramolecular hydrogen bonding and the asymmetry in the structure of regorafenib monohydrate is absent, in comparison to sorafenib.&lt;/p&gt;
</style></abstract><issue><style face="normal" font="default" size="100%">4</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">&lt;p&gt;
	Foreign&lt;/p&gt;
</style></custom3><custom4><style face="normal" font="default" size="100%">&lt;p&gt;
	4.6&lt;/p&gt;
</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Tumulu, Goutam Narayan</style></author><author><style face="normal" font="default" size="100%">Datar, Sarvesh</style></author><author><style face="normal" font="default" size="100%">Shelke, Ankita</style></author><author><style face="normal" font="default" size="100%">Swain, Gitanjali</style></author><author><style face="normal" font="default" size="100%">Ajithkumar, T. G.</style></author><author><style face="normal" font="default" size="100%">Thirumalaiswamy, Raja</style></author><author><style face="normal" font="default" size="100%">Mohan, Ojus</style></author><author><style face="normal" font="default" size="100%">Mahajani, Sanjay M.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Effect of sulfonation density on acid strength in ion exchange resins: Insights from solid-state NMR and density functional theory</style></title><secondary-title><style face="normal" font="default" size="100%">Molecular Catalysis</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Acid strength</style></keyword><keyword><style  face="normal" font="default" size="100%">Density functional theory</style></keyword><keyword><style  face="normal" font="default" size="100%">heterogeneous catalysis</style></keyword><keyword><style  face="normal" font="default" size="100%">Ion-exchange resins</style></keyword><keyword><style  face="normal" font="default" size="100%">Solid acids</style></keyword><keyword><style  face="normal" font="default" size="100%">Solid-state NMR</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2026</style></year><pub-dates><date><style  face="normal" font="default" size="100%">MAR </style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">593</style></volume><pages><style face="normal" font="default" size="100%">115794</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;
	Ion-exchange (IE) resins are widely used as solid acid catalysts; however, their surface acidity remains poorly characterized because their limited thermal stability precludes conventional NH3-based acidity measurements. Moreover, acid-site accessibility in IE resins is strongly governed by solvent- or reactant-induced swelling. Here, we investigate the surface acidity of commercial Amberlyst and Indion IE resins using &amp;amp; sup3;&amp;amp; sup1;P MAS NMR (Magic Angle Spinning Nuclear Magnetic Resonance), employing TMPO as a molecular probe dispersed on the resin with moderately swelling dichloromethane, thereby capturing the swollen-state acidity relevant for predicting catalytic activity. The deconvolution of the P-31 MAS NMR spectra reveals three distinct acid-strength zones arising from inhomogeneous sulfonation of the polymer matrix. The overall acidity, quantified by the area-weighted average P-31 chemical shift (delta), increases monotonically with sulfonation density. Notably, only resins containing acid sites stronger than similar to 80 ppm exhibited measurable catalytic activity in alpha-pinene isomerization, establishing a direct correlation between acidity and activity. Density functional theory (DFT) calculations on representative resin models, supported by electron-density analyses, attribute the enhancement of acid strength at higher sulfonation densities to cooperative hydrogen-bonding networks among neighboring sulfonic acid groups. Together, these findings establish P-31 MAS NMR-derived surface acidity as a catalytically relevant descriptor for the rational selection of IE resins in liquid phase acid-catalyzed chemistries.&lt;/p&gt;
</style></abstract><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">&lt;p&gt;
	Foreign&lt;/p&gt;
</style></custom3><custom4><style face="normal" font="default" size="100%">&lt;p&gt;
	4.9&lt;/p&gt;
</style></custom4></record><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Nadol, Athulya</style></author><author><style face="normal" font="default" size="100%">Ajithkumar, T. G.</style></author><author><style face="normal" font="default" size="100%">Singla, Rashmi</style></author><author><style face="normal" font="default" size="100%">Alex, T. C.</style></author><author><style face="normal" font="default" size="100%">Kumar, Sanjay</style></author><author><style face="normal" font="default" size="100%">Bhatt, Himal</style></author><author><style face="normal" font="default" size="100%">Deo, M. N.</style></author><author><style face="normal" font="default" size="100%">Sen, Debasis</style></author><author><style face="normal" font="default" size="100%">Ambashta, R. D.</style></author><author><style face="normal" font="default" size="100%">Bajpai, R. K.</style></author><author><style face="normal" font="default" size="100%">Shivakumar, Y. C.</style></author><author><style face="normal" font="default" size="100%">Manohar, S.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Fly-ash-based geopolymers: leachability and solid-state NMR investigations</style></title><secondary-title><style face="normal" font="default" size="100%">Bulletin of Materials Science</style></secondary-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">aluminosilicate network</style></keyword><keyword><style  face="normal" font="default" size="100%">Fly ash</style></keyword><keyword><style  face="normal" font="default" size="100%">Geopolymers</style></keyword><keyword><style  face="normal" font="default" size="100%">leaching</style></keyword><keyword><style  face="normal" font="default" size="100%">Solid-state NMR</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">2026</style></year><pub-dates><date><style  face="normal" font="default" size="100%">MAR</style></date></pub-dates></dates><volume><style face="normal" font="default" size="100%">49</style></volume><pages><style face="normal" font="default" size="100%">54</style></pages><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">&lt;p&gt;
	This study aims to explore how leaching impacts the microstructure of a selected fly ash-derived geopolymer and evaluate its potential for near-surface disposal of radioactive waste. The uniqueness of this geopolymer formulation is its ability to form an aluminosilicate network that remains resistant to structural changes upon contact with water. The leach index of base elements such as Ca, Al, Na and Si was between 11 and 13, suggesting that the formulation is superior to Portland cement or conventional hydraulic cement. Solid-state NMR reveals that the water-interacted specimen has no contamination of the zeolite phase and all the Na is incorporated into the aluminosilicate geopolymer gel network, which also confirms that the glassy network of the geopolymer is responsible for imparting low leachability of base elements from its structure, and there is no labile sodium available for exchange as in zeolites.&lt;/p&gt;
</style></abstract><issue><style face="normal" font="default" size="100%">2</style></issue><work-type><style face="normal" font="default" size="100%">Article</style></work-type><custom3><style face="normal" font="default" size="100%">&lt;p&gt;
	Foreign&lt;/p&gt;
</style></custom3><custom4><style face="normal" font="default" size="100%">&lt;p&gt;
	2.1&lt;/p&gt;
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