Chain architectures of various cellulose-based antiscalants on the inhibition of calcium carbonate scale

Two series of cellulose-based antiscalants with different chain architectures, i.e., linear carboxymethyl cellulose (CMC) and branch-shaped carboxymethyl cellulose-graft-poly(acrylic acid) (CMC-g-PAA), were synthesized. The carboxyl groups were distributed on CMC backbone but mainly on the grafted chains of CMC-g-PAA. The addition of CMC and CMC-g-PAA can both increase the surface energy of CaCO3 scale and decrease its crystal nucleation rate, thereby inhibiting CaCO3 scale formation. The structural effects of these cellulose-based antiscalants, especially the chain architectures, on the scale inhibition were investigated in detail. High degree of carboxymethyl substitution caused better inhibition effect of linear CMC. However, CMC-g-PAA with an appropriate content of carboxyl groups but high average number of PAA grafted chains can achieve high inhibition performance. Besides, with similar contents of carboxyl groups, CMC-g-PAA showed much better inhibition performance than CMC due to the distinct multi-dimensional spatial structure of graft copolymer in solution, causing the enhanced chelation and dispersion effects. Characterization of CaCO3 crystal by scanning electron microscopy and X-ray diffraction confirmed that crystal distortion effect obviously existed in CMC but quite minor in CMC-g-PAA. The differences between the scale-inhibition performance of CMC and CMC-g-PAA should be attributed to the different scale-inhibition mechanisms originated in their distinct chain architectures.

Artificial Bloodfeeder Glytube: Evaluating Different Types of Membranes and Blood Sources for Feeding Aedes aegypti and Aedes albopictus

ABSTRACT Mosquito colony maintenance in the laboratory is essential for research but presents logistical and ethical problems with the use of live animals for bloodfeeding. The Glytube is an artificial bloodfeeding system for mosquitoes that uses Parafilm-M® membrane and human blood to feed Aedes aegypti. This study evaluated the efficiency of Glytube with different types of membranes and chicken blood to feed Ae. aegypti and Ae. albopictus. We evaluated 2 artificial (thread seal tape [TST], Parafilm-M) and 2 natural membranes (pork, sheep intestine). The results for Ae. aegypti suggest that TST was the best membrane because it presented a high percentage of fed females (63%), a high average number of eggs per female (54.65), and an egg viability rate significantly similar to control (mouse). For Ae. albopictus, there was no significant difference between the membranes and the control; however, the use of TST is suggested due to the low cost and easy manipulation. The treatments that used chicken blood did not present significant differences in the egg viability when compared with the control. The Glytube functionality can be increased by replacing the Parafilm-M membrane by TST and human to chicken blood.

Production and Marketing of Carp Species in Rupandehi, Nepal

The research was conducted from January 2019 to June 2019 to study the fish production and marketing system in fish zone, Rupandehi. Altogether 95 respondents including 27 small farmers, 35 medium farmers and 33 large farmers were selected for household survey using simple random sampling for the study. Statistical tools, Ms- excel and SPSS of version 23 were used for data analysis. From the study, it was evident that, six species of carps of fingerlings size were stocked with high average number of common carps (3885.5/ha.) followed by silver carp (3880.5/ha). The average production of fish species was 6.06ton/ha which is slightly higher than the national average. The observed data revealed that, marketing of major quantity of fish was from on farm sale i.e. 55.78% followed by local market sale (18.94%), live fish sale in retailers (5.26%). Similarly, percentage of farmers selling fish to wholesaler, consumers, retailers and neighbours were 63.3%, 30.5%, 26.5% and 26.3% respectively. Cost and returns analysis showed average B/C ratio of 2.13. Problem ranking using 5 point scale value showed high cost of feed as the most serious problem with index value of 0.94 in the study area.

Geophysical methods for determining the reservoir properties of complexly constructed Lower and Middle Jurassic deposits within the oil-gas fields of the Ob River Region

This paper discusses the use of geophysical well logging for the interpretation of complex structure oil-saturated intervals of the Lower and Middle Jurassic horizons with high average number of permeable intervals, the content of minerals — semiconductors (pyrite, siderite, glauconite, et al.) for structuring a complex of geological and geophysical information and developing a researching methodology of areas with hard to recover reserves on example of deposits which was in operation for an extended period of time.

Optimisation of a Lawsonia inermis L. micropropagation protocol and acclimatization in a hydroponic culture

Lawsonia inermis is an important industrial and medicinal plant, cultivated mostly for dye production which is used in cosmetic industry. The objective of this study was establishing an efficient in vitro propagation system in order to obtain plants that will be acclimatized and grown hydroponically. The effect of different media on in vitro rooting were examined, followed by growing obtained microplants in a hydroponic culture, in a half-strength modified Hoagland nutrient solution. The highest rooting rate (79.2%) was recorded on the half-strength MS media containing 0.50 mg.L-1 IBA, with a high average number of roots (7.4). Those microplants acclimatized well in a hydroponic culture, where very rapid growth was recorded, and well developed roots and shoots were formed. After transplanting plants from hydroponic to soil, the survival rate was 100%. This is the first study reporting an acclimatization procedure in a hydroponic for the henna plant.