1,197 research outputs found
Small Farm Goat Production in Semi-Arid Region of Uttar Pradesh
Majority of selected goat farmers were landless and marginal (69%) with an annual average income of Rs.I9200.00. However, average income of small and medium goat farmers were about Rs.25500.00.Ownership pattern of goats revealed that about 78% goats were owned by the landless and marginal farmers. Majority of the farmers had Barbari/Barbari type goats (54%) followed by non-descript (43%) and Sirohi type goats (3%). Furthermore, 69 per cent goat houses were of Kaccha type and 49 per cent of selected respondent availed private veterinary services for their goats however, 40 percent of the goat farmers used home remedies. Merely, 11 per cent of the respondents visited government veterinary hospitals Though, poor socio-economic status cannot be ignore for the goat improvement in study village, some policy support is imperative to encourage goat farmers for their overall development
Shallow Deep Transitions of Neutral and Charged Donor States in Semiconductor Quantum Dots
We carry out a detailed investigation of neutral () and charged ()
impurity states of hydrogen-like donors in spherical semiconductor quantum
dots. The investigation is carried out within the effective mass theory (EMT).
We take recourse to local density approximation (LDA) and the Harbola-Sahni
(HS) schemes for treating many-body effects. We experiment with a variety of
confining potentials: square, harmonic and triangular. We observe that the
donor level undergoes shallow to deep transition as the dot radius () is
reduced. On further reduction of the dot radius it becomes shallow again. We
term this non-monotonic behaviour \textbf{SHADES}. This suggests the
possibility of carrier {\textbf{\textit{``freeze out''}}} for both and
. Further, our study of the optical gaps also reveals a {\textbf{SHADES}}
transition.Comment: 19 pages, 8 figures, Revised Versio
Aryabhata and the Construction of the First Trigonometric Table
Few among us would know that the first mention of the sine and the
enumeration of the first sine table are to be credited to Aryabhata. The method
to generate this relies on the sine difference formula which is derived using
ingenious arguments based on similar triangles. We describe how this was done.
In order to make our presentation pedagogical we take a unit circle and radians
instead of the (now) archaic notation in the Aryabhatiya and its commentators.
We suggest a couple of exercise problems and invite the enterprising student to
try their hands. We also point out that his sine and the second sine difference
identities are related to the finite difference calculus we now routinely use
to calculate derivatives and second derivatives. An understanding of these
trigonometric identities and preparation of the sine table will enable a
student to get an appreciation of the path breaking work of Aryabhata.Comment: 11 pages and 2 figures one of the figures is .png the other figure is
embedded as tik
The Band Gap in Silicon Nanocrystallites
The gap in semiconductor nanocrystallites has been extensively studied both
theoretically and experimentally over the last two decades. We have compared a
recent ``state-of-the-art'' theoretical calculation with a recent
``state-of-the-art'' experimental observation of the gap in Si nanocrystallite.
We find that the two are in substantial disagreement, with the disagreement
being more pronounced at smaller sizes. Theoretical calculations appear to
over-estimate the gap. Recognizing that the experimental observations are for a
distribution of crystallite sizes, we proffer a phenomenological model to
reconcile the theory with the experiment. We suggest that similar
considerations must dictate comparisons between the theory and experiment
vis-a-vis other properties such as radiative rate, decay constant, absorption
coefficient, etc.Comment: 5 pages, latex, 2 figures. (Submitted Physical Review B
Efficient removal of nanoplastics from synthetic wastewater using electrocoagulation
Nanoplastics are emerging contaminants that have now transformed into a
worldwide environmental concern. It is a lesser-known fact that several
emerging contaminants, such as bisphenol and perfluoro alkylates adsorbing on
micro and nanoplastics, could invade the food chain and cause irreversible
damage to human health and the environment. Even though wastewater treatment
plants (WWTPs) have been around for a long time, their removal strategy needs
to be improved since this is one of the main routes that micro and nanoplastics
get into the environment. UV deterioration, mechanical stresses, and biological
processes cause plastics to break apart and turn into smaller pieces. They get
small enough to be called nanoplastics, i.e. 1 um. We studied the removal of
nanoplastics from synthetic wastewater using an electrocoagulation process. We
used the polystyrene nanoparticles as nanoplastics synthesized from the
expanded polystyrene waste (EPS). For studies on electrocoagulation (EC),
aluminium electrodes were used in parallel combination at low voltage
conditions. We take advantage of the release of gas bubbles from the process to
enable the removal from the top by scraping them off. We studied the influence
of various process parameters on removing nanoplastics, such as electrode
spacing, salt concentration, and applied voltage. We found that a maximum
removal efficiency of more than 95% could be achieved at a specific electrolyte
concentration and pH of 7.2 +/- 0.3, illustrating that EC is a successful
technique for removing nanoplastic pollutants from the aquatic environment. The
advantage of the proposed method is that when nanoplastics and coagulants are
mixed, they help make a foamy layer on top of the reactor that can be easily
scraped off. The results of this study could serve as baseline information for
achieving massive nanoplastics cleanup on a larger scale in an eco-friendly
way.Comment: 26 pages, 8 figure
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