Deposits of clastic carbonate-dominated (calciclastic) sedimentary slope systems in the rock record have been identified mostly as linearly-consistent carbonate apron deposits, even though most ancient clastic carbonate slope deposits fit the submarine fan systems better. Calciclastic submarine fans are consequently rarely described and are poorly understood. Subsequently, very little is known especially in mud-dominated calciclastic submarine fan systems. Presented in this study are a sedimentological core and petrographic characterisation of samples from eleven boreholes from the Lower Carboniferous of Bowland Basin (Northwest England) that reveals a >250 m thick calciturbidite complex deposited in a calciclastic submarine fan setting. Seven facies are recognised from core and thin section characterisation and are grouped into three carbonate turbidite sequences. They include: 1) Calciturbidites, comprising mostly of highto low-density, wavy-laminated bioclast-rich facies; 2) low-density densite mudstones which are characterised by planar laminated and unlaminated muddominated facies; and 3) Calcidebrites which are muddy or hyper-concentrated debrisflow deposits occurring as poorly-sorted, chaotic, mud-supported floatstones. These

Phd by thesis

A biological method was used to synthesize stable silver nanoparticles that were tested as mosquito larvicides against Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus. Annona squamosa leaf broth (5%) reduced aqueous 1 mM AgNO₃ to stable silver nanoparticles with an average size of 450 nm. The structure and percentage of synthesized nanoparticles was characterized by using ultraviolet spectrophotometry, X-Ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy methods. The median lethal concentrations (LC₅₀) of silver nanoparticles that killed fourth instars of Ae. aegypti, Cx. quinquefasciatus, and An. stephensi were 0.30, 0.41, and 2.12 ppm, respectively. Adult longevity (days) in male and female mosquitoes exposed as larvae to 0.1 ppm silver nanoparticles was reduced by ~30% (p<0.05), whereas the number of eggs laid by females exposed as larvae to 0.1 ppm silver nanoparticles decreased by 36% (p<0.05).

Green synthesis of silver nanoparticles for the control of mosquito vectors of malaria, filariasis, and dengue.

Mosquitoes transmit major communicable diseases such as dengue, malaria, filariasis, Japanese encephalitis, chikungunya, and so on. Vector control is important in epidemic disease situations as there is an urgent need to develop new and improved mosquito control methods that are economical and effective yet safe for non-targeted organisms. In the present study, silver nanoparticles (AgNPs) were synthesized from the aqueous leaf extract of neem plant (Azadirachta indica), and their effects on mosquito vectors (Aedes aegypti and Culex quinquefasciatus) were assessed. The synthesised AgNPs were characterized by UV–vis spectroscopy, scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FT-IR), and X-ray diffraction analysis (XRD). The nanoparticles have maximum absorption at 442 ± 1.5 nm with an average size of 41–60 nm. The XRD data showed six well-defined diffraction peaks, corresponding to a relative intensity of the crystal structure of metallic silver 36.42, 100.00, 53.70, 14.20, 16.05, and 6.79, respectively. The FT-IR data showed strong prominent peaks in different ranges, reflecting its complex nature. The mosquito larvae were exposed to varying concentrations of AgNPs synthesized from the neem leaves under investigation (0.07–25 mg/l) for 24 h; this revealed larvicidal activity of AgNPs with LC50 and LC90 values of 0.006 and 0.04 mg/l for A. aegypti, respectively. Further, the LC50 and LC90 values were also identified as 0.047 and 0.23 mg/l for Cx. quinquefasciatus, respectively. The result obtained from this study presents biosynthesized silver nanoparticle from A. indica as the biolarvicidal agent with the most potential for mosquito control.

Synthesis of silver nanoparticles from Azadirachta indica—a most effective method for mosquito control

Historical development of methods and theoretical basis of differential thermal analysis (DTA) are outlined. DTA is a procedure in which the heat transfer toward the sample plays an important function and the associated process in the sample is manifested by deviation of temperature difference from its background. This difference ΔT is not directly proportional to the rate of the process (dα/dt) but includes also the effect of heat inertia proportional to the slope dΔT/dt as it was derived and incorporated into DTA equation by Vold (Anal Chem 21:683–688, 1949), Borchardt and Daniels (J Am Chem Soc 79:41–46, 1957), and suggested to be corrected in the authors’ previous papers (1976). However, the correction with respect to heat inertia has so far been omitted (particularly after the boom of non-isothermal kinetics started by paper of Kissinger (Anal Chem 29:1702–1706, 1957)). DTA experiments with rectangular pulses realized by micro-heater inside the sample show that the correction of DTA signal employing calculated heat inertia term of the DTA equation is reliable but not yet fully sufficient. It was a reason to derive a more complete DTA equation including a term expressing the changes in the temperature field inside the sample during process. Possibilities for improving of DTA (and DSC) data processing are discussed. Itemized 150 references with titles.

Heat inertia and temperature gradient in the treatment of DTA peaks

Using the Lie algebraic method the vibrational energy levels of HCCF and HCCD are calculated for 102 and 110 vibrational bands, respectively, using the local Hamiltonian. A comparative study is made between the two. Better results are obtained than those published earlier from local mode analysis.

RESEARCH ARTICLE An algebraic approach to the comparative study of the vibrational spectra of monofluoroacetylene (HCCF) and deuterated acetylene (HCCD)

Using Lie algebra the vibrational energy levels of HCN were calculated using the local Hamiltonian for 35 vibrational bands. A comparative study was made with earlier results.

An algebraic approach to the study of the vibrational spectra of HCN

An algebraic approach to the comparative study of the vibrational spectra of monofluoroacetylene (HCCF) and deuterated acetylene (HCCD)

An algebraic model of coupled anharmonic oscillators is introduced, capable of describing the stretching vibrations of medium and large polyatomic molecules. This model is applied to the calculation of Cm–H and C β –C β vibrational modes of nickel octaethyl porphyrins and nickel porphyrins molecules. The model appears to describe the data accurately.

Vibrational spectroscopy of Cm–H, C β –C β stretching vibrations of Nickel metalloporphyrins: An algebraic approach

The stretching and bending vibrational energies of SnBr4 and CCl4 are calculated in the one-dimensional framework. The dynamical symmetry group of tetrahedral molecule was taken into consideration to construct the model Hamiltonian in this framework. Casimir and Majorana invariant operators were also determined accordingly. Using the model Hamiltonian so constructed, we reported the vibrational energy levels of SnBr4 and CCl4 molecules accurately.

Nirmal Kumar Sarkar

Papers

An algebraic approach to the study of the vibrational spectra of HCN

RESEARCH ARTICLE An algebraic approach to the comparative study of the vibrational spectra of monofluoroacetylene (HCCF) and deuterated acetylene (HCCD)

An algebraic approach to the comparative study of the vibrational spectra of monofluoroacetylene (HCCF) and deuterated acetylene (HCCD)

Vibrational spectroscopy of Cm–H, C β –C β stretching vibrations of Nickel metalloporphyrins: An algebraic approach

Vibrational spectroscopy of SnBr4 and CCl4 using Lie algebraic approach