CONSTRUCTION OF ATAL TUNNEL

Atal tunnel is the world’s longest highway tunnel at an altitude of about 10,000 feet from the Mean Sea Level (MSL). It was formerly known as the Rohtang tunnel and was renamed after India’s former prime minister Atal Bihari Vajpayee. The length of the tunnel is 9.02 Km. It is also the longest bi-directional, single tube roadway tunnel of India and a project of great strategic importance. It is built with modern technologies and specifications in the Pir Panjal Range of Himalayas. The construction method for this tunnel is based on the philosophy of NATM. During construction of this tunnel, the team faced many challenges, unexpected difficulties like sudden collapse, ingress of water from pores of rocks etc. The team overcame such difficulties by solving the challenges using different methods. This paper will briefly give an overview of the strategic importance of the tunnel, geology of the site, construction technologies implemented, challenges faced during constructions and how the team overcame those

Impact of Hydrogen and Halogen Bonding Interactions on the Packing and Ionicity of Charge-Transfer Cocrystals

With an aim of understanding the influence of robust charge-transfer (CT) interactions and auxiliary hydrogen and halogen bonds in tailoring the crystal packing, we have synthesized four CT cocrystals involving 1,5-diaminonaphthalene (DAN) as the donor and fluoranil (FA), chloranil (CA), bromanil (BA), and iodanil (IA) as acceptors. While the CT interactions take the primary role in guiding the three-dimensional assembly in all the cocrystals, N–H···O and C–H···O hydrogen bonds play a significant role as auxiliary interactions in stabilizing the mixed stack arrangement in DAN–FA, DAN–CA, and DAN–BA cocrystals, whereas I···N halogen bonds assist the segregated stack supramolecular packing in DAN–IA. The experimentally determined ionicity values of mixed stack DAN–CA and DAN–BA cocrystals were found to be 0.27 and 0.23 e, indicating significant CT that increases with electronegativity of the halogen substituents

Solubility and Stability Advantage of Aceclofenac Salts

The nonsteroidal anti-inflammatory drug aceclofenac was screened with pharmaceutically acceptable coformers to discover novel solid forms of improved solubility. First, the X-ray crystal structure of aceclofenac (ACF) was analyzed to contain the rare carboxylic acid catemer O–H···O synthon, stabilized by auxiliary C–H···O and Cl···O interactions. Slurry grinding of aceclofenac with different coformers in a fixed stoichiometry resulted in salts with cytosine (1:1), piperazine (1:0.5), l-lysine (1:1), and γ-aminobutyric acid (1:1). The problem of drug cyclization to give the inactive indolinone byproduct is avoided in the mild conditions of salt formation. All the salts were characterized by spectroscopic methods, thermal analysis, and X-ray diffraction. Aceclofenac-l-lysine salt showed 135 times faster intrinsic dissolution rate (IDR) and 127 times higher area under the curve (AUC) compared to aceclofenac. ACF–LYS is a high solubility salt that is stable in the accelerated International Conference on Harmonization (ICH) conditions of 40 °C and 75% relative humidity for 8 months

Solubility and Stability Advantage of Aceclofenac Salts

The nonsteroidal anti-inflammatory drug aceclofenac was screened with pharmaceutically acceptable coformers to discover novel solid forms of improved solubility. First, the X-ray crystal structure of aceclofenac (ACF) was analyzed to contain the rare carboxylic acid catemer O–H···O synthon, stabilized by auxiliary C–H···O and Cl···O interactions. Slurry grinding of aceclofenac with different coformers in a fixed stoichiometry resulted in salts with cytosine (1:1), piperazine (1:0.5), l-lysine (1:1), and γ-aminobutyric acid (1:1). The problem of drug cyclization to give the inactive indolinone byproduct is avoided in the mild conditions of salt formation. All the salts were characterized by spectroscopic methods, thermal analysis, and X-ray diffraction. Aceclofenac-l-lysine salt showed 135 times faster intrinsic dissolution rate (IDR) and 127 times higher area under the curve (AUC) compared to aceclofenac. ACF–LYS is a high solubility salt that is stable in the accelerated International Conference on Harmonization (ICH) conditions of 40 °C and 75% relative humidity for 8 months

Solubility and Stability Advantage of Aceclofenac Salts

The nonsteroidal anti-inflammatory drug aceclofenac was screened with pharmaceutically acceptable coformers to discover novel solid forms of improved solubility. First, the X-ray crystal structure of aceclofenac (ACF) was analyzed to contain the rare carboxylic acid catemer O–H···O synthon, stabilized by auxiliary C–H···O and Cl···O interactions. Slurry grinding of aceclofenac with different coformers in a fixed stoichiometry resulted in salts with cytosine (1:1), piperazine (1:0.5), l-lysine (1:1), and γ-aminobutyric acid (1:1). The problem of drug cyclization to give the inactive indolinone byproduct is avoided in the mild conditions of salt formation. All the salts were characterized by spectroscopic methods, thermal analysis, and X-ray diffraction. Aceclofenac-l-lysine salt showed 135 times faster intrinsic dissolution rate (IDR) and 127 times higher area under the curve (AUC) compared to aceclofenac. ACF–LYS is a high solubility salt that is stable in the accelerated International Conference on Harmonization (ICH) conditions of 40 °C and 75% relative humidity for 8 months

Solubility and Stability Advantage of Aceclofenac Salts

The nonsteroidal anti-inflammatory drug aceclofenac was screened with pharmaceutically acceptable coformers to discover novel solid forms of improved solubility. First, the X-ray crystal structure of aceclofenac (ACF) was analyzed to contain the rare carboxylic acid catemer O–H···O synthon, stabilized by auxiliary C–H···O and Cl···O interactions. Slurry grinding of aceclofenac with different coformers in a fixed stoichiometry resulted in salts with cytosine (1:1), piperazine (1:0.5), l-lysine (1:1), and γ-aminobutyric acid (1:1). The problem of drug cyclization to give the inactive indolinone byproduct is avoided in the mild conditions of salt formation. All the salts were characterized by spectroscopic methods, thermal analysis, and X-ray diffraction. Aceclofenac-l-lysine salt showed 135 times faster intrinsic dissolution rate (IDR) and 127 times higher area under the curve (AUC) compared to aceclofenac. ACF–LYS is a high solubility salt that is stable in the accelerated International Conference on Harmonization (ICH) conditions of 40 °C and 75% relative humidity for 8 months

Solubility and Stability Advantage of Aceclofenac Salts

The nonsteroidal anti-inflammatory drug aceclofenac was screened with pharmaceutically acceptable coformers to discover novel solid forms of improved solubility. First, the X-ray crystal structure of aceclofenac (ACF) was analyzed to contain the rare carboxylic acid catemer O–H···O synthon, stabilized by auxiliary C–H···O and Cl···O interactions. Slurry grinding of aceclofenac with different coformers in a fixed stoichiometry resulted in salts with cytosine (1:1), piperazine (1:0.5), l-lysine (1:1), and γ-aminobutyric acid (1:1). The problem of drug cyclization to give the inactive indolinone byproduct is avoided in the mild conditions of salt formation. All the salts were characterized by spectroscopic methods, thermal analysis, and X-ray diffraction. Aceclofenac-l-lysine salt showed 135 times faster intrinsic dissolution rate (IDR) and 127 times higher area under the curve (AUC) compared to aceclofenac. ACF–LYS is a high solubility salt that is stable in the accelerated International Conference on Harmonization (ICH) conditions of 40 °C and 75% relative humidity for 8 months

Solubility and Stability Advantage of Aceclofenac Salts

The nonsteroidal anti-inflammatory drug aceclofenac was screened with pharmaceutically acceptable coformers to discover novel solid forms of improved solubility. First, the X-ray crystal structure of aceclofenac (ACF) was analyzed to contain the rare carboxylic acid catemer O–H···O synthon, stabilized by auxiliary C–H···O and Cl···O interactions. Slurry grinding of aceclofenac with different coformers in a fixed stoichiometry resulted in salts with cytosine (1:1), piperazine (1:0.5), l-lysine (1:1), and γ-aminobutyric acid (1:1). The problem of drug cyclization to give the inactive indolinone byproduct is avoided in the mild conditions of salt formation. All the salts were characterized by spectroscopic methods, thermal analysis, and X-ray diffraction. Aceclofenac-l-lysine salt showed 135 times faster intrinsic dissolution rate (IDR) and 127 times higher area under the curve (AUC) compared to aceclofenac. ACF–LYS is a high solubility salt that is stable in the accelerated International Conference on Harmonization (ICH) conditions of 40 °C and 75% relative humidity for 8 months

Room‐Temperature Ferroelectricity in an Organic Cocrystal

Ferroelectric materials exhibit switchable remanent polarization due to reversible symmetry breaking under an applied electric field. Previous research has leveraged temperature‐induced neutral‐ionic transitions in charge‐transfer (CT) cocrystals to access ferroelectrics that operate through displacement of molecules under an applied field. However, displacive ferroelectric behavior is rare in organic CT cocrystals and achieving a Curie temperature (TC) above ambient has been elusive. Here a cocrystal between acenaphthene and 2,3,5,6‐tetrafluoro‐7,7,8,8‐tetracyanoquinodimethane is presented that shows switchable remanent polarization at room temperature (TC=68 °C). Raman spectroscopy, X‐ray diffraction, and solid‐state NMR spectroscopy indicate the ferroelectric behavior is facilitated by acenaphthene (AN) rotation, deviating from conventional design strategies for CT ferroelectrics. These findings highlight the relevance of non‐CT interactions in the design of displacive ferroelectric cocrystals.Switchable remanent polarization at room temperature is displayed by the organic charge‐transfer cocrystal AN‐F4TCNQ. The ferroelectric Curie temperature was measured at 68 °C by differential scanning calorimetry, prompting further electronic and structural characterization of AN‐F4TCNQ which revealed that dynamic motion of acenaphthene (AN) contributes to the high‐temperature polarization switching.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145367/1/anie201805071.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145367/2/anie201805071-sup-0001-misc_information.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145367/3/anie201805071_am.pd

Room‐Temperature Ferroelectricity in an Organic Cocrystal

Ferroelectric materials exhibit switchable remanent polarization due to reversible symmetry breaking under an applied electric field. Previous research has leveraged temperature‐induced neutral‐ionic transitions in charge‐transfer (CT) cocrystals to access ferroelectrics that operate through displacement of molecules under an applied field. However, displacive ferroelectric behavior is rare in organic CT cocrystals and achieving a Curie temperature (TC) above ambient has been elusive. Here a cocrystal between acenaphthene and 2,3,5,6‐tetrafluoro‐7,7,8,8‐tetracyanoquinodimethane is presented that shows switchable remanent polarization at room temperature (TC=68 °C). Raman spectroscopy, X‐ray diffraction, and solid‐state NMR spectroscopy indicate the ferroelectric behavior is facilitated by acenaphthene (AN) rotation, deviating from conventional design strategies for CT ferroelectrics. These findings highlight the relevance of non‐CT interactions in the design of displacive ferroelectric cocrystals.Schaltbare Restpolarisierung bei Raumtemperatur wird für den organischen Ladungstransferkokristall AN‐F4TCNQ beobachtet. Die Curie‐Temperatur für den ferroelektrischen Übergang wurde mit dynamischer Differenzkalorimetrie zu 68 °C bestimmt. Die anschließende elektronische und strukturelle Charakterisierung von AN‐F4TCNQ ergab, dass dynamische Bewegungen von Acenaphthen (AN) zu der hohen Wechseltemperatur der Polarisierung beitragen.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145232/1/ange201805071.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145232/2/ange201805071-sup-0001-misc_information.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145232/3/ange201805071_am.pd