1,037 research outputs found
Guest-Shape-Directed Structural Switching between Two Isomers of a Pd6 Host and Its Structural Adaptability for Selective Photodimerization
No full textThe structure and functions of metal–organic cages are heavily dependent on the nature of the building blocks. Herein, a dimethyl-substituted propane diamine blocked cis-Pd(II) acceptor (A) was designed, which upon self-assembly with the tri-imidazole ligand (L), generated an unusual A6L4 octahedral cage (M1O) instead of the expected isomeric double-square architecture that was obtained from the tetramethyl-substituted ethylene diamine blocked cis-Pd(II) acceptor in water. Interestingly, in the presence of planar guests (Gn), M1O showed a transformation to a transient double-square architecture (M1DS), forming host–guest complexes with two such guests, (Gn)2@M1DS. The transient double-square cage (M1DS) readily converts back to the parent octahedral structure, M1O upon the removal of the guests. On the contrary, tetrahedral guests (G5/G6) stabilized the octahedral isomer of the host (M1O) by acting as suitable templates. Additionally, tetrahedral guests could induce the reverse transformation of M1DS to M1O by driving out planar guests from metastable M1DS. The specific antiparallel orientation and proximity of two anthracene derivatives within M1DS enabled them to be selectively transformed to the trans isomers of their respective dimers under photoirradiation. Upon dimer formation, the nonplanar product was expelled readily from the cavity of M1DS, and the host switched back to its original octahedral form (M1O), which functionally and structurally imitates enzymatic activity. Thus, a multifunctional supramolecular host was obtained that showed unique guest-shape-driven reversible structural switching and acted as an adaptive host for selective photodimerization
Formation of a Pd16 Molecular Basket Architecture of Reduced Symmetry and Angular Deviation in a Fluorenone Scaffold to Govern the Host–Guest Chemistry of Pd6 Trifacial Tubes
No full textThe employment of flexible ligands with significant conformational freedom in coordination-driven self-assembly enables the formation of unique and intricate structures. In this study, the self-assembly of such a fluorenone-appended ligand (L1) with a sterically demanding acceptor, [Pd(tmed)(ONO2)2] (M1), generated a new and unique molecular basket architecture, (M1)16(L1)8 (B), featuring a large hollow cavity. B possesses an unusual twisted architecture of low symmetry, consisting of 16 Pd(II) centers arranged as four tetrahedra connected by eight flexible ligands, representing a structurally complex system reminiscent of biological architectures. Designing such entropically disfavored, large architectures of reduced symmetry is challenging but desirable, since they can act as ideal models to study complicated natural systems. The host–guest property of supramolecular hosts is governed by the confined cavities and noncovalent interactions, which are dictated by the angular disposition of ligand coordination sites. To explore this, the fluorenone scaffold was used to synthesize two other tetradentate ligands (L2 and L3) that differed in the spatial distributions of their coordination vectors. The self-assembly of these ligands with [Pd(en)(ONO2)2] (M2) resulted in the formation of water-soluble (M2)6(L1/L2/L3)3 trifacial tubes of different geometries with varying internal cavity dimensions. These angular variations further altered the orientation of the fluorenone carbonyl groups within the cavities, thereby modulating their guest binding abilities and highlighting the importance of tailoring supramolecular hosts for specific guest binding
Stimuli‐Mediated Structural Interchange Between Pd6 and Pd12 Architectures: Selective Recognition of E‐Stilbene by the Pd6 Architecture and its Photoprotection
No full textThe dynamic behaviour of metal-ligand bonding cultivates stimuli-mediated structural transformations in self-assembled molecular architectures. The propensity of synthetically designed self-assembled systems to interchange between higher-order architectures is increased multi-fold when the building blocks have higher conformational degrees of freedom. Herein, we report a new ligand, (2,7-bis(di(pyridin-4-yl)amino)-9H-fluoren-9-one) (L), which, upon self-assembly with a cis-[(ethylene-1,2-diamine)Pd(NO3)2] acceptor (M), resulted in the formation of a M6L3 trifacial barrel (C1) in water. Interestingly, during crystallization, a rare M12L6 triangular orthobicupola architecture (C2) was generated along with C1. C2 could also be generated in solution via the application of several stimuli. C1 in aqueous media could stabilize one trans-stilbene (tS) or cis-stilbene (cS) molecule in its cavity, with a selectivity for the former from their mixture. Moreover, C1 acted as an effective host to prevent the otherwise facile photoisomerization of tS to cS inside its hydrophobic cavity under UV irradiation. Conversely, the visible-light-induced reverse isomerization of encapsulated cS to encapsulated tS could be achieved readily due to the better stabilization of tS within the cavity of C1 and its transparency to visible light. A multi-functional system was therefore designed, which at the same time is stimuli-responsive, shows isomer selectivity, and photo-protects trans-stilbene
Postassembly Modification of a Pd6 Host and C70 Encapsulation to Enhance Its ROS-Mediated Terpene Oxidation Ability under Visible Light
No full textThe properties of supramolecules can be modulated by post-assembly modification (PAM) of their building blocks or via guest encapsulation. This work demonstrates a largely uncharted approach to property modulation that integrates both PAM and guest encapsulation in a single system to boost photocatalytic activity. Self-assembly of a “phenothiazine”-functionalized ligand (L) with a cis-blocked Pd(II) acceptor (A) generated an A6L3 trifacial tube (T). Postassembly, T could be modified via irradiation with violet light, leading to the sulfoxidation of the “phenothiazine” moieties in T and thereby generating an oxidized tube (TO). Both TO and T could stabilize a C70 molecule within their cavities, forming C70@TO and C70@T, respectively. Although T showed relatively poor photocatalytic performance mediated by reactive oxygen species (ROS) with respect to oxidation of terpenes (S1–S4) under visible light, the modified TO was much better in that regard. Expectedly, C70@T showed better photocatalytic performance than T due to the presence of photosensitizing C70. While PAM or guest encapsulation alone led to reasonable improvements in photocatalytic ability, their combination within C70@TO led to a significant improvement. Catalytic amounts of C70@TO could instantly oxidize terpenes. Thus, we report here a new host that integrates the effects of both PAM and photosensitizer encapsulation for synergistically boosting its photocatalytic activity
A Stacked Segmented Adaptive Power Amplifier in 22nm FD-SOI
No full textThis work was supported by Soitec. (Corresponding author: Aritra Banerjee.
Author Exchange
No full textAnthropologist Mukulika Banerjee and political scientist Sushmita Pati have a conversation about their recently published books set in rural Bengal and Delhi’s urban villages, respectively. They situate their analyses of the intersections between democracy, capitalism, urbanization, and globalization in events, relations, and cultures of the everyday. Their exchange offers important insights for how political subjectivities and social ties are differently constituted or, to use Banerjee’s term, “cultivated” in these two settings. The two books offer a fine-grained view of how active citizenship in rural and urban India is refracted through distinct social and institutional structures. India is home to some of the world’s largest cities while more than 900 million people continue to live in the countryside. Its democratic future is therefore inextricably tied to the evolution of political behavior and political economy in both contexts, and, as Banerjee and Pati’s joint response indicates, to how urban and rural dynamics shape each other through (but not only through) migrants and their networks.
Contents:
Review of Mukulika Banerjee’s \u27Cultivating Democracy: Politics and Citizenship in Agrarian India\u27 by Sushmita Pati
Response from Mukulika Banerjee
Review of Sushmita Pati’s \u27Properties of Rent: Community, Capital and Politics in Globalising Delhi\u27 by Mukulika Banerjee
Response from Sushmita Pati
Joint Commentary from Banerjee and Pat
Banerjee_QSurvey_RawDataSet_PPC
No full textRaw dataset for questionnaire survey study (kinesiology taping_cancer care continuum)Author: Gourav Banerjee et alJournal: Progress in Palliative Care</div
FEMININE VISIBILITY IN A MYTHOLOGICAL CONTEXT OF CHITRA BANERJEE DIVAKARUNI’S THE PALACE OF ILLUSIONS
No full textChitra Banerjee Divakaruni an Indo-American author, works as a professor of English in the University of Houston. She is also a co-founder and former president of a helpline for South Asian women. She involves herself eagerly as a volunteer at women’s center at Berkeley and assists battered women through the organization. MAITRI, the organization was begun in 1991 by her with the help of a group of friends. Chitra Banerjee Divakaruni an expatriate writer, pictures Indian womanhood how they are treated by men in their lives. An explicit attempt to retell the epic in novel form is Chitra Banerjee Divakaruni’s The Palace of Illusions which will be analyzed in the following. The present paper analyzes how women is treated by male as a lifeless thing in the novel. This study is an attempt to illustrate how revisionist mythmaking is a feminist endeavor to revalue the experiences of women in patriarchy and redefine women from feminist perspectives.
 
Data for: Virtual Nondestructive Evaluation of Anisotropic Plates by Implementing Symmetry Informed Sequential Mapping of Anisotropic Green’s function (SISMAG)
No full textNo data should be used without permission from the corresponding the author. With permission, data can be used for only non-commercial purposes
Nobel Laureate Abhijit Vinayak Banerjee: A Scientometric Portrait, 1987-2019
No full textNobel Memorial Prize in economics is selected by the Royal Swedish Academy of Sciences and first awarded in the domain in 1969; the latest in 2019 was awarded to the Indian-born American economist Prof. Abhijit Vinayak Banerjee along with Esther Duflo and Michael Kremer. The present study attempted to measure and analyse the research publications of Prof. Banerjee during 1987 to 2019 based on the data available in Google Scholar database. A total of 333 documents published during this period in which 35.74 percent were published as journal articles. Till 2004 the mean relative growth rate of his publications was 0.237 and doubling time was 3.29 whereas from 2005 to 2019 the relative growth rate decreased to 0.077 and the time for doubling increased to 10.20. Esther Duflo was the most prolific co-author of the publications of Prof. Banerjee with 120 documents shared out of 333 by them. The collaboration rate of all publications was 0.89 identifies most of his publications written in collaboration. The journal he used for most of his research to publish was mainly USA based. He has produced numbers of publications which received huge citations, and during May, 2020 the h-index counted 87 according to Goggle Scholar citation counts
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