Caffeine, Its Basicity, Acidity, Hydrolysis & Spectrophotometric Assay

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Coarsening and Slow-Dynamics in Granular Compaction

We address the problem of the microscopic reorganization of a granular medium under a compaction process in the framework of Tetris-like models. We point out the existence of regions of spatial organization which we call domains, and study their time evolution. It turns out that after an initial transient, most of the activity of the system is concentrated on the boundaries between domains. One can then describe the compaction phenomenon as a coarsening process for the domains, and a progressive reduction of domain boundaries. We discuss the link between the coarsening process and the slow dynamics in the framework of a model of active walkers on active substrates.Comment: Revtex 4 pages, 4 figures, in press in PRL. More info http://axtnt3.phys.uniroma1.it/Tetri

Correlation between prevalence rates of pulmonary tuberculosis, tuberculous infection and non-specific sensitivity

Data from the initial examination of a BCG trial have been analysed to determine mathematical relationship, if any, between the prevalence of infection and disease. Also, because non-specific sensitivity otters protection against the development of tuberculosis and because there was high prevalence of nonspecific sensitivity in the area of the study, relationship between nonspecific sensitivity and tuberculosis had also been studied. Results of the analysis showed that relationship between prevalence of tuberculous infection and disease is not amenable to any simple mathematical quantification. However, the values of the coefficients of correlation between the two were statistically highly significant suggesting that the prevalence of one varied directly with the prevalence of the other in the community, and that preve-lence of infection may be used as an indicator for the prevalence of disease at different points of time. The analysis also showed the existence of an inverse relationship between prevalence of tuber-culosis ane prevalence of non-specific sensitivity tending to confirm the previous finding that the latter offered protection against the other

Coulomb Interactions and Nanoscale Electronic Inhomogeneities in Manganites

We address the issue of endemic electronic inhomogeneities in manganites using extensive simulations on a new model with Coulomb interactions amongst two electronic fluids, one localized (polaronic), the other extended (band-like), and dopant ions. The long range Coulomb interactions frustrate phase separation induced by the strong on site repulsion between the fluids. A single quantum phase ensues which is intrinsically and strongly inhomogeneous at a nano-scale, but homogeneous on meso-scales, with many characteristics (including colossal responses)that agree with experiments. This, we argue, is the origin of nanoscale inhomogeneities in manganites, rather than phase competition and disorder related effects as often proposed.Comment: 4 pages, 3 figure

Rheology of HTPB Propellant: Effect of Mixing Speed and Mixing Time

The effect of mixer blade speed and mixing cycle time on the rheological behaviour of an optimized HTPB-based propellant formulations has been studied keeping the temperature constant. Variations in yield stress and viscosity at unit shear rate have been determined as a function of time for different mixing speeds. The effect of mixing on the extent of pseudoplasticity has been represented in the form of a bar chart. A correlation in terms of shear and yield stresses has been developed for viscosity index, i.e., the viscosity at unit shear rate as a function of mixer blade speed

Population genetics of Drosophila nasuta nasuta, Drosophila nasuta albomicana and their hybrids. I. Karyotypic mosaicism in the hybrid populations

D. n. nasuta and D. n. albomicana constitute a pair of chromosomal races with 2n=8 and 2n=6, respectively. The F1 of these has 2n=7 and it is fertile. There exists a state of karyotypic mosaicism as evidenced by the presence of 26 types of chromosome combinations in F2, F3 and F10 populations. In the midst of this karyotypic noise, the karyotype similar to that of F1 reached 51% of the population. Implications of these findings are discussed

Synthesis and Characterisation of Diaryl Furoxans

The paper discusses the synthesis, characterisation, and performance evaluation of diarylfuroxans namely, bis-phenyl-3,4-furoxan (5) and bis-(4’-nitrophenyl)-3,4-furoxan (6). Themolecules have been synthesised on the lines of reported method by cyclodimerisation of thenitrile oxides generated from benzaldoxime and p-nitro benzaldoxime, respectively. The synthesisedfuroxans (5 ) and (6) were characterised by the elemental analysis, UV, IR, and 1H NMRspectroscopy. The hazard characteristics (impact and friction sensitivity) confirm that thecompounds are safe to handle. The oxygen balance, velocity of detonation and detonationpressure have been computed. The detonation velocity and pressure along with oxygen balanceincreased with the substitution of nitro group in the benzene ring, as expected. Thethermogravimetric studies on promising compound (6) brings out that maximum weight lossoccurs at decomposition temperature of 259–260 °C

PRELIMINARY ANALYTICAL STUDY OF SAINDHAVADYA GHRUTA

Ghruta is considered best among the Snehas. Its usage is being highlighted by our Acharyas in the disorders of brain like Unmada, Apasmara etc. This study focuses on one such preparation Saindhayadya ghruta mentioned in Yogaratnaka Apasmara chikitsa. Literary review done through various sources like books, journals and internet revealed that, no studies have been carried out on this formulation yet. Hence an attempt was made to study Saindhayadya ghruta through qualitative and quantitative analysis of Physico-chemical parameters and to develop fingerprints of High-Performance Thin Layer chromatography study (HPTLC). HPTLC densitometric scan of chloroform extract of unsaponifiable matter of Saindhvadhya Ghruta showed 9 and 6 spots at 254nm and 366nm respectively. To interpret the results, there are no previous standard markers established for Saindhavadya ghruta. This analytical profile may help in the identification of Saindhavadya ghruta in future and to maintain the standard quality of the formulation

Studies on the ontogenetic changes in the isozymes in Drosophila nasuta nasuta and Drosophila sulfurigaster neonasuta

Ontogenetic manifestations of four isozymes namely, acid phosphatase, alkaline phosphatase, α-esterase and β-esterase have been analysed in two closely related species- D. nasuta nasuta and D. sulfurigaster neonasuta. By adopting polyacrylamide gel electrophoretic technique 15 different developmental stages have been assayed. Electrophoretically homologous and distinct enzyme phenotypes for each enzyme system have been recognised in the two species under study. The implications of these findings are discussed