Meltblown nanofiber media for enhanced quality factor     

Rohit Uppal  Gajanan Bhat  Chris Eash  Kokouvi Akato 《Fibers and Polymers》2013,14(4):660-668

Nanofibers definitely hold great advantage and promise in filtration as they have very high specific surface area, which ensures greater probability of capturing the particles and hence, the filtration efficiency of the nanofiber filter media is high. Electrospun nanofibers are prohibitively expensive due to extremely low production rate. With recent advances in melt blowing technology, nanofibers could be produced at production rate few orders of magnitude higher than that of conventional single syringe electrospinning and hence, quite cost effective. Influence of air pressure and die to collector distance (DCD) were studied on the number average fiber diameter for the nanofibers as well as the performance properties of the nonwoven webs, each factor at three discrete levels. The nanofibers were as fine as 260 nm. A very encouraging observation of the study is very high values of quality factor observed for nanofiber nonwoven filter media. In order to compare the filtration efficiency of different nanofiber nonwoven media samples with different basis weight, a novel term of specific filtration efficiency is proposed and was found that the specific filtration efficiency with the increase in DCD or air pressure.  相似文献   

Characterization of Spray-Dried Hydrolyzed Proteins from Pink Perch Meat Added with Maltodextrin and Gum Arabic     

Lakshmi Narasimha Murthy  Girija Gajanan Phadke  Chitradurga Obaiah Mohan  Madhamuthanalli Venkataramappa Chandra  Jeyakumari Annamalai  Sivam Visnuvinayagam 《Journal Of Aquatic Food Product Technology》2017,26(8):913-928

In the present study, spray-dried pink perch meat protein hydrolysate (PPH) and hydrolysate with maltodextrin and gum arabic (PPHMG) were characterized in relation to their physical, rheological, functional, antioxidant, thermal, and sensory properties. The Herschel–Bulkley model was suitable to explain the flow behavior of PPH and PPHMG emulsions. Both the samples exhibited functional and antioxidant properties. Antioxidant activities were significantly higher for PPH compared with PPHMG (p<0.05). PPH and PPHMG alone did not exhibit antimicrobial activity but enhanced the activity of chitosan against pathogens. Sensory acceptability of the samples in soup revealed that PPHMG of up to 4% was highly scored without any traces of bitterness, whereas for PPH, a concentration of up to 3% was acceptable.  相似文献   

Critical carbon inputs to maintain soil organic carbon stocks under long‐term finger‐millet (Eleusine coracana [L.] Gaertn.) cropping on Alfisols in semiarid tropical India     

Cherukumalli Srinivasarao  Bandi Venkateswarlu  Anil Kumar Singh  Kanuparthy Pandu Ranga Vittal  Sumanta Kundu  Gajjala Ravindra Chary  Ganjigunte Narayanaiyer Gajanan  Basavapura Kogganur Ramachandrappa 《植物养料与土壤学杂志》2012,175(5):681-688

Enrichment of soil organic carbon (SOC) stocks through sequestration of atmospheric CO₂ in agricultural soils is important because of its impacts on adaptation to and mitigation of climate change while also improving crop productivity and sustainability. In a long‐term fertility experiment carried out over 27 y under semiarid climatic condition, we evaluated the impact of crop‐residue C inputs through rainfed fingermillet (Eleusine coracana [L.] Gaertn.) cropping, fertilization, and manuring on crop yield sustainability and SOC sequestration in a Alfisol soil profile up to a depth of 1 m and also derived the critical value of C inputs for maintenance of SOC. Five treatments, viz., control, farmyard manure (FYM) 10 Mg ha^–1, recommended dose of NPK (50 : 50 : 25 kg N, P₂O₅, K₂O ha^–1), FYM 10 Mg ha^–1 + 50% recommended dose of NPK, and FYM 10 Mg ha^–1 + 100% recommended dose of NPK imposed in a randomized block design replicated four times. Application of FYM alone or together with mineral fertilizer resulted in a higher C input and consequently built up a higher C stock. After 27 y, higher profile SOC stock (85.7 Mg ha^–1), C build up (35.0%), and C sequestration (15.4 Mg C ha^–1) was observed with the application of 10 Mg FYM ha^–1 along with recommended dose of mineral fertilizer and these were positively correlated with cumulative C input and well reflected in sustainable yield index (SYI). For sustenance of SOC level (zero change due to cropping) a minimum quantity of 1.13 Mg C is required to be added per hectare per annum as inputs. While the control lost C, the application of mineral fertilizer served to maintain the priori C stock. Thus, the application of FYM increased the C stock, an effect which was even enhanced by additional amendment of mineral fertilizer. We conclude that organic amendments contribute to C sequestration counteracting climate change and at the same time improve soil fertility in the semiarid regions of India resulting in higher and more stable yields.  相似文献   

Identifying other suitable and potential indigenous carrageenophytes for commercial cultivation in India     

Veeragurunathan  V.  Prasad  Kamalesh  Alphons Sequeira  Rosy  Meena  Ramavatar  Gajanan Kavale  Monica  Grace  P. Gwen 《Aquaculture International》2022,30(4):2001-2015

In India, Kappaphycus alvarezii is the only alga being cultivated commercially for kappa carrageenan production and also being utilized for the socioeconomic upliftment of coastal rural population in India in the form of their cultivation and marketing. The production has been substantially increased from 21 dry tonnes to 1490 dry tonnes with increasing market purchase value from US$ 0.061 to 0.469 kg dry wt^?1 during 2001–2013. In India, annual import for carrageenan is 1800–2000 M tons year^?1 and its demand is reported to be increased by 5–6% every year (Mantri et al. 2017). To date, Aquagri Pvt Ltd is the only company in India producing kappa carrageenan from cultivated Kappaphycus alvarezii (Mantri et al. 2017). However, few other marine phycocolloid processing factories are producing kappa carrageenan from Hypnea musciformis and Hypnea valentiae at cottage level. The total annual production of carrageenan in India ranges between 100 and 132 tons. There is tremendous demand for other carrageenan such as iota and lambda carrageenan in food, beverage, and consumer product manufacturing industries. In order to ascertain suitability of unexplored other indigenous carrageenophytes for commercial cultivation in India, several red algal species such as Agardhiella subulata, Ahnfeltiopsis pygmaea, Laurencia caraibica, and Solieria robusta were collected from wild habitats in Kanyakumari (N 08°08′10.36″; E 077°34′28.06″) Tamil Nadu, India, and were evaluated for their mariculture potential and the presence of carrageenan. Preliminary cultivation experiments were carried out by raft culture method (1?×?1 m) for 45 days at two harvest cycles at Thonithurai (N 09°16′53.45″; E 079°11′19.22″), Tamil Nadu, South eastern coast of India. Except Ahnfeltiopsis pygmaea, all other seaweeds investigated showed daily growth rate (DGR) in the range of 1.59 to 3.822% and confirmed its mariculture potential. Phycocolloid was extracted with yield 4.5 to 29.37% from dry seaweed residues obtained after extraction of lipids using both water and aqueous alkali [5% Ca (OH)₂ solution]. Water was found the better solvent in terms of higher yield of the Phycocolloid (29.37%) from Solieria robusta. FT-IR of the extracted phycocolloid indicated presence of characteristic bands for carrageenan in all the samples. However, from the band positions, the presence of iota carrageenan was ascertained in the Agardhiella subulata and Solieria robusta and hybrid iota/kappa carrageenan is expected to be present in Laurencia caraibica and Ahnfeltiopsis pygmaea.

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Mechanisms of resistance to diflubenzuron in the house fly, Musca domestica (L.)     

Gajanan D. Pimprikar  George P. Georghiou 《Pesticide biochemistry and physiology》1979,12(1):10-22

The mechanisms of resistance to the chitin synthesis inhibitor diflubenzuron were investigated in a diflubenzuron-selected strain of the house fly (Musca domestica L.) with > 1000 × resistance, and in an OMS-12-selected strain [O-ethyl O-(2,4-dichlorophenyl)phosphoramidothioate] with 380 × resistance to diflubenzuron. In agreement with the accepted mode of action of diflubenzuron, chitin synthesis was reduced less in larvae of the resistant (R) than of a susceptible (S) strain. Cuticular penetration of diflubenzuron into larvae of the R strains was about half that of the S. Both piperonyl butoxide and sesamex synergized diflubenzuron markedly in the R strains, indicating that mixed-function oxidase enzymes play a major role in resistance. Limited synergism by DEF (S,S,S-tributyl phosphorotrithioate) and diethylmaleate indicated that esterases and glutathione-dependent transferases play a relatively small role in resistance. Larvae of the S and R strains exhibited a similar pattern of in vivo cleavage of ³H- and ¹⁴C-labeled diflubenzuron at N₁C₂ and N₁C₁ bonds. However, there were marked differences in the amounts of major metabolites produced: R larvae metabolized diflubenzuron at considerably higher rates, resulting in 18-fold lower accumulation of unmetabolized diflubenzuron by comparison with S larvae. Polar metabolites were excreted at a 2-fold higher rate by R larvae. The high levels of resistance to diflubenzuron in R-Diflubenzuron and R-OMS-12 larvae are due to the combined effect of reduced cuticular penetration, increased metabolism, and rapid excretion of the chemical.  相似文献   

In situ bioremediation of organochlorine‐pesticide‐contaminated microcosm soil and evaluation by gene probe     

Asifa Qureshi  M Mohan  Gajanan S Kanade  Atya Kapley  Hemant J Purohit 《Pest management science》2009,65(7):798-804

BACKGROUND: Pesticide‐formulating industries are contaminating the environment through various activities. Bioremediation is the best method for decontamination, as chemical and physical methods are not only costly but also not very effective in open field systems. In the present study, in situ bioremediation of organochlorine‐contaminated soil was demonstrated by combined biostimulation and bioaugmentation strategies, followed by evaluation using a molecular method. RESULTS: Three parameters were monitored: microbial biomass (colony‐forming units (CFU) g^?1 soil), residual pesticides after treatment and catabolic genes from microcosm soil. Both the biostimulation and the bioaugmentation treatments showed an initial lag phase of 80 days towards colony‐forming units. Gas chromatography of soil samples showed that concentrations of residual pesticides in the soil declined by up to 85–90% after 80 days, indicating their utilisation with time. On dot‐blot hybridisation of the total DNA from the same soil samples, it was observed that catabolic genes tfdC (catechol 1,2‐dioxygenase) and cm genes (chlorophenol monoxygenase) were predominant, whereas other catabolic genes such as catechol 2,3‐dioxygenase (xylE) were negligible. CONCLUSION: The strategy of in situ bioremediation and its evaluation by gene probe and also by conventional methods was demonstrated for organochlorine‐pesticide‐contaminated soil in open microcosms. It showed that bioaugmentation along with biostimulation was effective, although initial acclimatisation for a period of almost 2–3 months was required in the open field systems. Copyright © 2009 Society of Chemical Industry  相似文献