902 research outputs found
The Conversational Quality of Literature: An Interview with Neel Mukherjee
No full textNeel Mukherjee, author of The Lives of the Others and A State of Freedom talks about his education, his readings, his career as a reviewer and lately as a novelist. He discusses some of the issues brought up by his novels, such as capitalism, the predicament of the have-nots, and literary influences
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
Planar Bridging-Droplet Thermal Diode
No full textThis disclosure provides a thermal diode including a first plate having a first surface defining a wick structure. The thermal diode can include a second plate having a smooth surface facing the wick structure, the smooth surface and the wick structure defining a chamber for accommodating a phase-change liquid. The thermal diode also can include a separator positioned between the first plate and the second plate to separate the wick structure from the smooth surface by a gap that is less than a capillary length of the phase-change liquid
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
Bharati Mukherjee, conquering America
No full textAuthor Bharati Mukherjee discusses her works and what it means to be an Asian immigrant in the United States.Host, Bill Moyers. Director of photography, Eric Camiel ; editor, Michael Collins ; theme music, Michael Bacon
The Conversational Quality of Literature: An Interview with Neel Mukherjee
No full textNeel Mukherjee, author of The Lives of the Others and A State of Freedom talks about his education, his readings, his career as a reviewer and lately as a novelist. He discusses some of the issues brought up by his novels, such as capitalism, the predicament of the have-nots, and literary influences
203 - Subhojeet Mukherjee
No full textHere is a link to a recent CSU source publication on our exploits at the 1st Cyber Truck Challenge, Warren, Michigan: https://source.colostate.edu/cybertruck-challenge-students-hack-truck-steal-show/.Here is a link to our project website: http://www.cs.colostate.edu/dbsec/HeavyVehicle/.Here is a link to my personal website which lists some of my works in detail: http://www.cs.colostate.edu/~subhomuk/.Inside today's vehicles, embedded electronic control units (ECUs) manage different operations by communicating via the serial CAN bus. It has been shown that the CAN bus can be accessed by remote attackers to disrupt/manipulate normal vehicular operations. Heavy-duty vehicles, unlike their lighter counterparts, follow a common set of communication standards (SAE J1939) and are often used for transporting critical goods, thereby increasing their asset value. This work deals with the internal communication security of heavy-duty vehicles and is aimed at detecting /preventing malicious activities that can adversely affect human lives and company fortunes reliant on such modes of transportation.CSU Ventures Drivers of Innovation - Platinum award
Review: The Gene: An Intimate History. By Siddartha Mukherjee
No full textDr. Siddhartha Mukherjee, author of the highly regarded and Pulitzer Prize winning The Emperor of All Maladies, has undertaken what he terms as an “intimate history” of the gene. Mukherjee’s medical credentials are impressive, yet they are also atypical for research and writing on the history of science. The Gene is impeccably written and expands our understanding of a well-known history through his unique viewpoint. In fact, Mukherjee’s work is reminiscent of another Pulitzer Prize winner, Jared Diamond. Originally a physiologist, Diamond, is best known for applying his scientific viewpoint to the Spanish Conquest in his 1997 Pulitzer Prize winning Gun’s Germs, and Steel.
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