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Algae were investigated in the past as a potential source of biofuel and other useful chemical derivatives. Magnetic separation of algae by iron oxide nanoparticle binding to cells has been proposed by others for dewatering of cellular mass prior to lipid extraction. We have investigated feasibility of magnetic separation based on the presence of natural iron stores in the cell, such as the ferritin in Auxenochlorella protothecoides (A. p.) strains. The A. p. cell constructs were tested for inserted genes and for increased intracellular iron concentration by inductively coupled plasma atomic absorption (ICP-AA). They were grown in Sueoka's modified high salt media with added vitamin B1 and increasing concentration of soluble iron compound (FeCl3 EDTA, from 1× to 8× compared to baseline). The cell magnetic separation conditions were tested using a thin rectangular flow channel pressed against interpolar gaps of a permanent magnet forming a separation system of a well-defined fluid flow and magnetic fringing field geometry (up to 2.2 T and 1,000 T/m) dubbed “magnetic deposition microscopy”, or MDM. The presence of magnetic cells in suspension was detected by formation of characteristic deposition bands at the edges of the magnet interpolar gaps, amenable to optical scanning and microscopic examination. The results demonstrated increasing cellular Fe uptake with increasing Fe concentration in the culture media in wild type strain and in selected genetically-modified constructs, leading to magnetic separation without magnetic particle binding. The throughput in this study is not sufficient for an economical scale harvest.

Genus Macrobrachium includes freshwater prawns which inhabit most diverse habitats ranging from low saline areas to inland hill streams and impounded water bodies. Being morphologically conserved, this genus has been exposed to severe disputes related to their taxonomy, systematics and phylogeny. Macrobrachium striatum and M. equidens represent two morphologically related congeneric species within this genus. Earlier, M. striatum was considered as a striped form of M. equidens. Though these species are now well-described morphologically and differentiated into two species, no molecular level investigation has been carried out in support of their speciation. We report a study on M. striatum and M. equidens with emphasis to their molecular data through mitochondrial markers (16S ribosomal RNA and cytochrome oxidase subunit I). Results obtained from developed molecular markers of the two species revealed considerable genetic differentiation between them. Phylogram generated using Minimum evolution and Neighbour joining analyses differentiated M. striatum and M. equidens as two independent species. Genetic distance data showed high interspecific divergence (ranging from 3.9% to 17.0% for 16S rRNA sequences and 13.8% to 21.0% for COI sequences) between M. striatum and M. equidens confirming the findings of phylogram. Hence, it could be delineated that M. striatum and M. equidens represent two distinct species within genus Macrobrachium with emphasis to their morphology and genetics.

Oxygen content in air is approximately 21% by volume. With many industrial uses, mainly in the manufacture of steel and chemicals, for metal cutting, welding ,hardening & scarfing, it is being transported as a non-liquefied gas at pressures of 138 bar (13800000 Pa) or above, also as a cryogenic fluid at pressures and temperatures below 13.8bar (1380000 Pa) & −146.5°C (126.65K). Commonly we found air separation plants produce ultra-pure oxygen (> 99.9% purity) via liquefaction of atmospheric air and separation of the oxygen by fractionation and thereby transported to the needy areas via pipelines. The research efforts directed towards technical assessment to establish the correlations between valve construction and turbulence and solving the complications in the transported ultra-pure oxygen gas in the pipelines and through mounted valves. Hence, it is necessary to study the performance, complexities and fire hazards associated with the valves transporting it and the preventive measures to avoid any catastrophic failure in ultra-pure gaseous oxygen services. The study was conducted on two isolation valves — each of ball and globe of relative size. It was realized that velocities of the ultrapure gaseous oxygen on the impingement sites inside the valve are beyond the safe limit as recommended by European Industrial Gas Association (EIGA) [4] and various other prominent industrial gas manufacturers. Moreover, globe valve gave relatively less turbulence and velocity at initial opening of the valve. The study revealed that majority of health hazards & accidents on industrial usage of ultra-pure gaseous oxygen media are the result of the inadequate awareness of the degreasing or cleaning and optimum material selection and construction of the valve and fittings on the industrial pipeline.