Dezincification of Brass in Sulfide Polluted Sodium Chloride Medium: Evaluation of the Effectiveness of 2-Mercaptobenzothiazole

The present paper addresses the effectiveness of 2-mercaptobenzothiazole (MBT) in preventing the dezincification of brass in sulfide polluted 3.5% NaCl solution. The dezincification behaviour of brass in 3.5% NaCl solution containing 100-1000 ppm of sulfide ions and 1 x 10-6 to 1 x 10-3 M MBT was studied by potentiodynamic polarization, electrochemical impedance spectroscopy, current-time transient and accelerated leaching studies. The presence of sulfide ions in 3.5% NaCl solution has caused a significant increase in the extent of corrosion attack on brass. The inhibiting effect of MBT is markedly reduced in the presence of sulfide ions in the medium. The easy replacement of Cu-MBT complex by Cu2S film on the surface of brass is responsible for the inability of MBT to prevent corrosion attack in the presence of sulfide ions. The study concludes that the effectiveness of MBT in preventing the dezincification of brass is dependent on the concentration of the sulfide ions in the medium and the effectiveness is nullified at higher concentrations of sulfide ions

Cage culture requirements - Site selection and water quality needs

Culture of fish in cage is a popular method of rearing the fish along the coastal areas. Site selection and water quality is one of the most important factors that determine the success and failures of cage culture system. It also determines the cost of production and survival of the system in the long run. Controlling water quality parameters in open water cage culture systems is an impractical; therefore, culture of any species must be established in the sites having adequate water quality and frequent exchange. Before establishing a cage culture site, it is foremost important to conduct a field survey for gaining prior knowledge on the environmental/ hydro-biological parameters of the site so as to ascertain that the water body chosen will support the increased biological demand due to cage culture activities in due course of time

Direct observation of 4+ to 2+ gamma transition in 8Be

The low lying states in $^8$Be are believed to have a two-alpha cluster structure and hence a large intrinsic quadrupole deformation. An earlier calculation showed a large collective enhancement in gamma transition probability between the low lying states leading to a 4$^+$ to 2$^+$ gamma branch of $\sim10^{-7}$ and a resonant radiative cross section of 134 nb for the $\alpha+\alpha$ entrance channel. We report here the first experimental evidence for this transition through a $\gamma-\alpha-\alpha$ coincidence measurement in the reaction $^4$He($\alpha,\alpha \gamma$)$^4$He using a gas target. The measured cross sections on and off the 4$^+$ resonance are 165 $\pm$ 41 (stat) $\pm$35 (sys) nb and 39 $\pm$ 25 (stat) $\pm$7 (sys) nb, respectively.Comment: Total 4 pages, 4 figures, in RevTeX format, submitted to PR

ISOLATION, SCREENING AND CHARACTERIZATION OF L-ASPARAGINASE PRODUCING FUNGI FROM MEDICINAL PLANTS

Objective: To isolate and characterize of L-asparaginase producing fungi from medicinal plants.Methods: Fungal strains were isolated on standard media, characterized and were screened for their ability to produce L-asparginase, used in the treatment of certain types of cancers, using modified Czapek-Dox medium supplemented with L-asparagine.Results: A total of 10 fungal isolates were obtained from 3 plant leaf samples and two isolates exhibited significant L-aspargniase production. Fusarium sp. (SMGR-F1) isolated from the papaya leaves showed the maximum activity. The organism was grown under submerged fermentation conditions at 30 °C produced 111.07±1.53 IU/ml of L-asparaginase at 120 h.Conclusion: L-asparaginase is being effectively used for the treatment of acute lymphoblastic leukemia and tumor cells. Fusarium sp. was isolated from the papaya plant leaves showing significant L-asparaginase activity and thus can be further exploited for the commercial production of L-asparaginase.Â

Correcting the quantum clock: conditional sojourn times

Can the quantum-mechanical sojourn time be clocked without the clock affecting the sojourn time? Here we re-examine the previously proposed non-unitary clock, involving absorption/amplification by an added infinitesimal imaginary potential($iV_{i}$), and find it {\it not} to preserve, in general, the positivity of the sojourn time, conditional on eventual reflection or transmission. The sojourn time is found to be affected by the scattering concomitant with the mismatch, however small, due to the very clock potential($iV_{i}$) introduced for the purpose, as also by any prompt scattering involving partial waves that have not traversed the region of interest. We propose a formal procedure whereby the sojourn time so clocked can be corrected for these spurious scattering effects. The resulting conditional sojourn times are then positive definite for an arbitrary potential, and have the proper high- and low-energy limits.Comment: Corrected and rewritten, RevTeX, 4 pages, 2 figures (ps files) include

Evaluation of the early impacts of the better cotton initiative on smallholder cotton producers in Kurnool District, India: Baseline report

The Better Cotton Standard System is a holistic approach to sustainable cotton production that covers all three pillars of sustainability: environmental, social and economic. The main study research questions is - To what extent has the process of becoming or being certified under BCI sustainability standards had an impact (positive or negative, expected or unexpected) upon smallholders (farmers and households) in Kurnool district? What are the economic (yield, productivity, incomes, food security) and social (child labour, farm workers, no discrimination in wages for women) impacts? In order to be able to measure and attribute impact, but also to understand what has created impact and identify lessons, the study employs a theory based evaluation approach. The baseline and interim performance monitoring rounds of the research have been completed. The end line research is planned in 2018-19

Electromagnetic transition from the 4+^+ to 2+^+ resonance in 8^8Be measured via the radiative capture in 4^4He+4^4He

An earlier measurement on the 4$^+$ to 2$^+$ radiative transition in $^8$Be provided the first electromagnetic signature of its dumbbell-like shape. However, the large uncertainty in the measured cross section does not allow a stringent test of nuclear structure models. The present paper reports a more elaborate and precise measurement for this transition, via the radiative capture in the $^4$He+$^4$He reaction, improving the accuracy by about a factor of three. The {\it ab initio} calculations of the radiative transition strength with improved three-nucleon forces are also presented. The experimental results are compared with the predictions of the alpha cluster model and {\it ab initio} calculations.Comment: 5 pages and 7 figures, Submitted to Physical Review Letter