Mathematical Modeling And Experimental Studies On Biochemical Conversion Of Cr(Vi) Of Tannery Effluent To Cr(Iii) In A Chemostat

Biodegradation of hexavalent chromium present in tannery waste has been studied using Pseudomonas sp. (JUBTCr1) and Bacillus sp. (JUBTCr3) isolated from their native source. A 5L double-jacketed chemostat with 4L working volume has been used as contacting device for the kinetic investigation of the biodegradation process. Varying the feed volumetric rate from 118-133 ml/h for different inlet hexavalent chromium concentrations (30 to 90 mg/dm3), an attempt has been made to study the reaction engineering behavior of the system. It is observed that Haldane type substrate inhibited model can satisfactorily be used to predict the extent of bioconversion for different dilution rate. Using the kinetic parameters of proposed Haldane equation, a CSTR model was developed. Model prediction agreed well with experimental data

Development of Materials and Processing Technology for Rural Blacksmiths : A Package

Significant increase in agriculture products has been achieved in India through many avenues like use of better seeds, fertilizer, and irrigation yet less attention has been paid on improvement of the agriculture tools. Better tools and implements accelerate the agriculture product-ion and for this genuine sources of raw materials for implements are in demand. Considerable research work at National Metallurgical Laboratory (NML), Jamshedpur has proved the utility of improved agriculture tools. The traditional practice of rural blacksmiths for producing the tools is being challenged by the growing industries surrounding the villages. Modern industries at the urban sector have lured the rural youths to fill their pockets by the moderate pay packets. So they are eager to switch over to urban side leaving their traditional trades. Since a few of them are succeeded to get absorbed in the modern industries, most of them are forced to return to their villages and here comes the means of survival with the traditional trades unless the production technique is enhanced/updated. Various problems regarding raw mater-ials, education irtconnection with forging, design of implements and their heat treatment have been studied. Major phase of work, carried ou at NML was to provide technology for achieving suitable raw materials by back yard steel melting technique and establishment of appropr-iate forging and heat treatment schedule to meet the speci-fied standards. To provide technological support/ back up to practising blacksmiths of rural sectors, NML has asse-ssed the quality of existing tools and implements and suggested methods for life improvement. Keeping in view the economics, NML has developed a low cost fuel-efficient furnace with a marginal alteration of the existing (Mother earth) hearth furnace used by the rural blacksmiths. The efficiency of the furnace has been enhanced distinctively by reducing convective and radiative heat losses by controlling the pre heated air and natural airflow ratio through the blower. This furnace has such a design that the same can be used for heat treatment of the tools. Simultaneously, a manually operated mechanical hammer is also developed for sledging purpose.With this, blacksmiths can continue the forging operation single handedly with substantial ease and increased productivity

Distribution of dwell times of a ribosome: effects of infidelity, kinetic proofreading and ribosome crowding

Ribosome is a molecular machine that polymerizes a protein where the sequence of the amino acid residues, the monomers of the protein, is dictated by the sequence of codons (triplets of nucleotides) on a messenger RNA (mRNA) that serves as the template. The ribosome is a molecular motor that utilizes the template mRNA strand also as the track. Thus, in each step the ribosome moves forward by one codon and, simultaneously, elongates the protein by one amino acid. We present a theoretical model that captures most of the main steps in the mechano-chemical cycle of a ribosome. The stochastic movement of the ribosome consists of an alternating sequence of pause and translocation; the sum of the durations of a pause and the following translocation is the time of dwell of the ribosome at the corresponding codon. We derive the analytical expression for the distribution of the dwell times of a ribosome in our model. Whereever experimental data are available, our theoretical predictions are consistent with those results. We suggest appropriate experiments to test the new predictions of our model, particularly, the effects of the quality control mechanism of the ribosome and that of their crowding on the mRNA track.Comment: This is an author-created, un-copyedited version of an article accepted for publication in Physical Biology. IOP Publishing Ltd is not responsible for any errors or omissions in this version of the manuscript or any version derived from it. The definitive publisher authenticated version is available online at DOI:10.1088/1478-3975/8/2/02600

Time-resolved measurement of single pulse femtosecond laser-induced periodic surface structure formation

Time-resolved diffraction microscopy technique has been used to observe the formation of laser-induced periodic surface structures (LIPSS) from the interaction of a single femtosecond laser pulse (pump) with a nano-scale groove mechanically formed on a single-crystal Cu substrate. The interaction dynamics (0-1200 ps) was captured by diffracting a time-delayed, frequency-doubled pulse from nascent LIPSS formation induced by the pump with an infinity-conjugate microscopy setup. The LIPSS ripples are observed to form sequentially outward from the groove edge, with the first one forming after 50 ps. A 1-D analytical model of electron heating and surface plasmon polariton (SPP) excitation induced by the interaction of incoming laser pulse with the groove edge qualitatively explains the time-evloution of LIPSS formation.Comment: 4 pages, 5 figure