4-Amino­phthalimide

The mol­ecules in the title compound (systematic name: 5-aminoisoindole-1,3-dione), C8H6N2O2, are packed through N—H⋯O inter­molecular hydrogen-bonding inter­actions. Two types of hydrogen bonds are observed: one, involving the imide group, forms mol­ecular chains along the c axis and another two, involving the amino group, connect the mol­ecular chains

Structural Characterization of Quaterphenyl Cation Radical: X-ray Crystallographic Evidence of Quinoidal Charge Delocalization in Poly-\u3cem\u3ep\u3c/em\u3e-phenylene Cation Radicals

Quaterphenyl derivative (QP) containing tert-butyl solubilizing groups at the terminal positions yields a stable cation radical salt that was isolated, and its structure was established by X-ray crystallography. The crystal structure of neutral QP and its cation radical (QP+•SbCl6-) provides unequivocal evidence for the quinoidal stabilization of the cationic charge or polaron by smoothing out the torsional motion of the interconnected p-phenylene rings. Such an observation of stabilization of the cationic charge in a poly-p-phenylene (PPP) derivative forms the basis for the noted high conductivities in PPP oligomers in their doped state

Structural Characterization of Quaterphenyl Cation Radical: X-ray Crystallographic Evidence of Quinoidal Charge Delocalization in Poly-\u3cem\u3ep\u3c/em\u3e-phenylene Cation Radicals

Quaterphenyl derivative (QP) containing tert-butyl solubilizing groups at the terminal positions yields a stable cation radical salt that was isolated, and its structure was established by X-ray crystallography. The crystal structure of neutral QP and its cation radical (QP+•SbCl6-) provides unequivocal evidence for the quinoidal stabilization of the cationic charge or polaron by smoothing out the torsional motion of the interconnected p-phenylene rings. Such an observation of stabilization of the cationic charge in a poly-p-phenylene (PPP) derivative forms the basis for the noted high conductivities in PPP oligomers in their doped state

Isolation and X-ray Structural Characterization of Tetraisopropylpyrene Cation Radical

A practical synthesis of 1,3,6,8-tetraisopropylpyrene and the isolation and X-ray structural characterization of its monomeric cation radical salt are described

Practical Synthesis of Unsymmetrical Tetraarylethylenes and Their Application for the Preparation of [Triphenylethylene−Spacer−Triphenylethylene] Triads

We have demonstrated that reactions of diphenylmethyllithium with a variety of substituted benzophenones produces corresponding tertiary alcohols that are easily dehydrated, without any need for purification, to produce various unsymmetrical and symmetrical tetraarylethylenes in excellent yields. The simplicity of the method allows for the preparation of a variety of ethylenic derivatives in multigram (10−50 g) quantities with great ease. The methodology was successfully employed for the preparation of various triphenylethylene (TPE)-based triads (i.e., TPE−spacer−TPE) containing polyphenylene and fluoranyl-based spacers. The ready availability of various substituted tetraarylethylenes allowed us to shed light on the effect of substituents on the oxidation potentials (Eox) of various tetraarylethylenes. Moreover, the electronic coupling among the triphenylethylene moieties in various TPE−spacer−TPE triads was briefly probed by electrochemical and optical methods

Transition metal catalysed Grignard-like allylic activation across tetragonal tin(II) oxide

The reaction of allyl halide and a carbonyl compound under the aegis of tetragonal tin(II) oxide and catalytic d8, d10 metal complexes provides the corresponding homoallylic alcohol, via a novel allyl tin intermediate

Application of graph theoretic concepts in short circuit analysis of power systems.

The ever increasing size of electrical power systems necessitates systematic and comprehensive methods for their analysis. This report is concerned with the application of graph theoretic concepts in power system analysis, with particular reference to short circuits. It is demonstrated that the application of graph concepts provides a very elegant method for the formulation and analysis of power systems problems. -- The formulation is based on a decomposition of the power systems into a number of subsystems. The subsystems are then combined according to their physical interconnection pattern - so that an appropriate mathematically equivalent system representation is available for the system as a whole. Such a method is considered to be particularly suitable for the analysis of large power systems. -- The formulation of the ZBUS and YBUS models for a typical transmission system is given. Also, as an example, the multi-terminal representation for a typical system containing an auto-transformer is derived. The method of combining different subsystems, such as the transmission systems and the generator systems, is demonstrated. Building algorithms, using the concepts of multi-terminal representations, are developed such that the impedance matrix (ZBUS) of a network can be formulated in stages - by adding one element at a time. Separate cases for (i) addition of a branch, not mutually coupled (ii) addition of a link, not mutually coupled (iii) addition of a mutually coupled group, are illustrated. The symbolic formulations of these cases are discussed. Numerical examples to illustrate the use of these algorithms are worked out. Finally, an attempt is made to obtain the short circuit currents and voltages of a typical power system, by application of graph theoretic principles. Separate cases for three phase faults, as well as for two simultaneous faults, are considered. In each of these cases, numerical examples which illustrate the formulation procedure and analysis are worked out

COUGH AND CHEST PAIN WITH AN UNCOMMON CAUSE

Multiple  Hereditary  Exostoses  is  an  autosomal  dominant  disorder  with  multiple  cartilage  capped  bony  outgrowths  in  tibia  ,fibula, femur,  and  sometimes  the  ribs  and  scapula. They may  present  with  variety  of  symptoms  depending  on  the  structures  it  compresses  such  as  nerves,  arteries  or  may  lead  to  limb  deformities  or  may  cause  bursitis , or  may  undergo  malignant  transformation. A  33 year old  male  presented  to  our  outpatient  department  with  recurrent  cough  and  left  sided  chest  pain. On  evaluation  he  was  found  to  have  multiple  bony  outgrowths  in the scapula ,5th  rib , and  limbs. Similar  bony  outgrowths  were  also  present  in  his  father  and  grandfather. On  clinical  and  radiological  basis  a  diagnosis of  Multiple  Hereditary  Exostoses  was  made. His  symptoms  gradually  subsided  with  removal  of  the  rib  and  scapular  exostoses. Thus  evaluation  of  bony  structures  should  not  be  overlooked  in  cases  of  cough  and  chest  pain.Keywords: Cough, Chestpain, Multiple  Hereditary  Exostoses.Â