Large-cage zeolite structures with multidimensional 12-ring channels

Zeolite type structures with large cages interconnected by multidimensional 12-ring (rings of 12 tetrahedrally coordinated atoms) channels have been synthesized; more than a dozen large-pore materials were created in three different topologies with aluminum (or gallium), cobalt (or manganese, magnesium, or zinc), and phosphorus at the tetrahedral coordination sites. Tetragonal UCSB-8 has an unusually large cage built from 64 tetrahedral atoms and connected by an orthogonal channel system with 12-ring apertures in two dimensions and 8-ring apertures in the third. Rhombohedral UCSB-10 and hexagonal UCSB-6 are structurally related to faujasite and its hexagonal polymorph, respectively, and have large cages connected by 12-ring channels in all three dimensions.     

Triblock copolymer syntheses of mesoporous silica with periodic 50 to 300 angstrom pores

Use of amphiphilic triblock copolymers to direct the organization of polymerizing silica species has resulted in the preparation of well-ordered hexagonal mesoporous silica structures (SBA-15) with uniform pore sizes up to approximately 300 angstroms. The SBA-15 materials are synthesized in acidic media to produce highly ordered, two-dimensional hexagonal (space group p6mm) silica-block copolymer mesophases. Calcination at 500 degrees C gives porous structures with unusually large interlattice d spacings of 74.5 to 320 angstroms between the (100) planes, pore sizes from 46 to 300 angstroms, pore volume fractions up to 0.85, and silica wall thicknesses of 31 to 64 angstroms. SBA-15 can be readily prepared over a wide range of uniform pore sizes and pore wall thicknesses at low temperature (35 degrees to 80 degrees C), using a variety of poly(alkylene oxide) triblock copolymers and by the addition of cosolvent organic molecules. The block copolymer species can be recovered for reuse by solvent extraction with ethanol or removed by heating at 140 degrees C for 3 hours, in both cases, yielding a product that is thermally stable in boiling water.     

Application of silver nanoparticles to industrial sewing threads: Effects on physico-functional properties & seam efficiency

In this study, the role and impact of silver nanoparticles on industrial sewing threads have been investigated. Study of nanocoating on industrial sewing threads may be useful especially in the areas where skin comes in contact with the garments where anti-bacterial properties may be very useful. Silver particles are considered to have excellent anti bacterial properties. To understand the impact on sewability, investigation was focused to changes at the structural level, changes in physical and surface properties, tensile properties and anti-microbial properties of the nanotreated sewing threads. The structure and morphology of the silver nanoparticles on the sewing threads was observed by scanning electron microscopy (SEM) and quantitatively confirmed by fourier transform infrared spectroscopy (FT-IR). A number of experimental methods and mathematical formulae were used to test individual threads. Custom designed fixtures were used for the study. All the results have been statistically analyzed and found to be significant. The effect of silver nanoparticles on physical properties, functional properties and seam efficiency was illustrated. The difference of the impact of silver nanoparticles on cotton and polyester sewing threads has been compared. It was found that silver nanotreatment leads to a significant reduction of tensile strength. The warp-way seam strength increased where as weft-way seam strength decreased due to damage of yarn. Deformation properties of the threads are not influenced significantly by nanotreatment. The nanotreatment of threads improves its frictional properties significantly. The threads also acquire effective anti-microbial properties with silver nanotreatment. Study of the impact of nanotreatment on the properties of cotton and polyester samples showed a bigger impact on cotton samples than polyester samples. The effect was durable even after several laundering treatments.     

Basalt nanoparticle reinforced hybrid woven composites: Mechanical and thermo-mechanical performance

Nanoparticles are gaining wider importance and increasing utility in many areas of engineering and technology. This investigative work is conducted to study the effect of incorporating basalt nano particles in composites with basalt/basalt and basalt/jute woven structures as reinforcement. The nanoparticles were developed from basalt, they were characterized and used for reinforcing composites of basalt and jute hybrid fabrics. The mechanical and thermo-mechanical properties of hybrid woven basalt reinforced epoxy composites were evaluated. Microscopic examination was carried out in order to analyze the internal structure and fractured surfaces. Interfacial characteristics, material morphology and failure was studied by use of Scanning Electron Microscope (SEM) and optical microscopy. Thermal stability was characterized by TGA. The results elaborated that the incorporation of basalt nanoparticles exhibited superior properties compared to the pure epoxy resin impregnated basalt fabric reinforced composites in terms of mechanical and thermal stability.     

Effects of varied levels of incorporation of Labeo gonius in carp polyculture system in India

Growth performance of kuria labeo, Labeo gonius as a component species in the major carp polyculture system was evaluated at two incorporation levels against a control without the species through a year‐round grow‐out study in nine earthen ponds (0.08 ha). Three species ratio of catla, silver carp, rohu, mrigal and kuria labeo at 15:15:40:30:0 (T‐1: control), 15:15:40:20:10 (T‐2) and 15:15:40:10:20 (T‐3) were evaluated as three treatments. The carps were stocked at a combined density of 7500 fingerlings ha^?1. Silver carp demonstrated the highest survival (75–81%) followed by rohu (70–76%), catla (69–76%), kuria labeo (69–71%) and mrigal (67–69%). Species‐wise yield attributes such as survival, harvest weight, SGR and biomass yield of silver carp, catla and rohu were similar in their respective treatments. Kuria labeo at 10% inclusion demonstrated 12% higher harvest weight than its 20% inclusion. However, such higher weight gain could not affect the total biomass yields of carps which remained similar among the treatments. Furthermore, harvest weight of kuria labeo at 10% inclusion was comparable to that of mrigal when the latter incorporated at 20–30% level. Therefore, the study suggested 10% to be a suitable incorporation level for kuria labeo in the commercial grow‐out carp polyculture system.     

In vitro storage of fish oocytes: effect of storage temperature,media conditions and storage duration on fertilization and larval hatchability of Indian major carp,rohu (Labeo rohita)

The viability of matured oocytes stored in vitro were assessed using carp ovarian fluid (OF) and artificial carp ovarian fluid (ACOF) under different temperature regimes (4, 24, 26, 28 and 30°C) for different storage durations (0, 60, 120, 150 and 180 min). Significantly higher fertilization (74%) was achieved when the oocytes were stored using ACOF and 65% in OF after 180 min at 28°C. Similarly the hatching rates of larvae were significantly higher in the ACOF and OF, that is, 64% and 47%, respectively, after 180 min of storage. The oocytes kept in the storage containers with ACOF having 65% moisture level showed a significantly higher fertilization rate than the 59% moisture level. This study demonstrated that unfertilized matured oocytes (eggs) of rohu can be stored in vitro for 180 min without compromising the viability (fertilization and hatching) to a great extent in OF and ACOF.     

Studies in Forest Pathology

A survey for the parasitic alga. Cephaleuros virescens Künze in relation to its seasonal distribution in different forest types has been done. The alga was absent in gymnosperms and was common in angiosperms. The disease severity was more in summer and the rainy season and absent in winter, Combretum decandrum was found to be most susceptible to this parasite alga. Altogether 49 hosts were recorded out of which 26 were new host records. Healthy leaves contain higher amounts of total nitrogen and total phenol, whereas in algal infected leaves the amounts of total sugar, total amino acid and dry weight were higher.