Topochemical engineering of composite hybrid fibers using layered double hydroxides and abietic acid

Topochemical engineering of hybrid materials is an efficient way of synthesizing hydrophobic and highly tensile fiber composites by utilizing the intermolecular hydrogen bonds in natural materials. These materials include wood pulp fibers, abietic acid (resin acid) and inexpensive metal salts. In this work, a hybrid composite was created using bleached and unbleached kraft pulp fibers as cellulose platform. In situ co-precipitation of layered double hydroxide (LDH) was performed to grow LDH crystals on the surface of the cellulose fibers, followed by the immobilization of abietic acid (AA) on LDH-grafted cellulose. Here we aimed to benefit from the hydrogen bonding between -OH groups of cellulose and LDH, and the -COOH groups of AA to obtain charge-directed assembly of one material on the other material. Thus, composite hybrid fibers (C-HF) were produced and then characterized by optical (CAM), spectroscopic (XRD, IR) and microscopic techniques (SEM) to determine their average length and distribution, structure and purity, bonding, and morphology. These fibers further were tested for water contact angle (hydrophobicity), oil absorption (lipophilicity), tensile strength and ISO brightness measurements. The performance of C-HF was compared with unmodified reference fibers (REF), fibers composed with only AA (C-F) and LDH-hybridized fibers (HF). The results revealed a variety of correlations between materials and their properties due to characteristic surface morphology, functional groups, hydrogen bonding and natural co-materials such as lignin and hemicelluloses. Attractive and repulsive van der Waals forces between material entities play a crucial role in the resulting properties

Isolation and characterization of a novel agarolytic bacterium vibrio SP.B4-6A from coral reef ecosystem off Tutiocorin

Isolation and characterization of a novel agarolytic bacterium vibrio SP.B4-6A from coral reef ecosystem off Tutiocori

Observations on selected characteristics of water and sediment at the open sea cage culture site of Asian seabass Lates calcarifer (Bloch) off Cochin, south-west coast of India

Study was undertaken to assess the impact of open sea cage culture of Asian seabass Lates calcarifer on selected parameters of water as well as sediment at Munambam off Cochin, Kerala coast from November 2008 to March 2009. Periodic observations were made on temperature, pH, dissolved oxygen, salinity, nutrients (NO3, PO4, SiO3), nitrite, ammonia, BOD, total suspended solids, chlorophyll a, gross and net primary productivity as well as bacterial load of the surface and near bottom water from the cage site (N 10º 08' 162''; E 76º 08' 901'') and also from a reference site (N 10º 07' 189''; E 76º 09' 210'') during pre- as well as post-stocking periods. Sediment samples were collected simultaneously from both the sites and analysed for texture, pH, organic carbon and bacterial load. A significant reduction (p<0.05) in silicate and chlorophyll a was perceived in surface water at the cage site, during the culture period as compared to pre-stocking period. No significant variations were noticed in any of the other parameters studied. The sand, silt, clay and organic carbon content in sediment at cage site differed significantly (p<0.05) from that of the reference site. There was no significant difference in the mean values of total heterotrophic bacterial count as well as presumptive Vibrio count of the water and sediment, either between the cage site and reference site or between the pre- and post-stocking samplings. No adverse effect as influenced by cage culture of fish was observed on any of the environmental parameters studied during the period of investigation

First record of the sclerectinian coral Echinopora lamellosa from Minicoy, Lakshadweep

The sclerectinian coral Echinopora lamellosa (Esper, 1795) has been recorded from the Minicoy lagoon (8°18'10.7''N; 73o00’58.3"E) during an underwater survey on 3rd December 2015. This is a new record for the coral fauna of Minicoy island, Lakshadweep

भारतीय वन्य जीव(संरक्षण)अधिनियम के तहत संरक्षित उपास्थिमीन प्रजातियों का विवरण

कृपया पूरा लेखा पढ

लक्षद्वीप के चुने गए द्वीपों में समुद्री शैवालों की विविधता

समुद्री शैवाल माक्रोस्कोपिक, बहुकोशिकीय स्‍थूल शैवाल को संदर्भित करता है। समुद्र, मुहानों और पश् चजलों के उथले पानी में इन् हें पाया जाता है। भारतीय समुद्र से पाए जाने वाले अधिकांश समुद्री वाल मुख् यत: चार ग्रुपों में विभाजित कि या जाता है, जो कि क्‍लोरोफाइसिए, फियोफाइसिए, रोडोफाइसिए और सयनो फाइसिए। एगार, एगरोस, कैरागीनन और एल्जिनेट जैसे फाटो केमि कल्स के उत्‍पा दन के लिए समुद्री शैवालों का उपयोग किया जाता है

Characterisation of a carotenoid producing extremely halophilic archaeon Halorubrum sodomense MS5.1 isolated from a solar saltern in Tamil Nadu, South India.

A carotenoid producing extremely halophilic archaeon designated MS5.1 was isolated out of brine samples from a crystalliser pond of a marine solar saltern in Kanyakumari District, Tamil Nadu, South India. The red pigmented, long rod shaped haloarchaeon was found to be able to grow at temperature range of 20-40°C, salt concentration of 10-35% and pH range of 6 to 9 with optimum conditions for growth being 28°C; 30% salt and pH 7

Isolation and characterization of a halophilic archaeon Halorubrum sodomense from Manaikudi salt pans, Tamil Nadu, South India

Archaea are mostly unexplored and distinct class of microorganism with unique features and are commonly encountered in extreme environments They are phylogenetically more similar to eukarya than bacteria. Achaeal membrane lacks peptidoglycan but have different membrane lipid bonding Archaeal lipid lacks the fatty acid found in bacteria and eukaryotes and instead have side chains composed of repeating units of isoprene. They are key players of ocean biogeochemical cycles and potential source of novel natural products including chemicals and biomolecules. The present study attempted isolation and characterization of a halophilic archaeon from a solar saltern situated at Manaikkudi Village in Nagercoil District, Tamil Nad

Biodegradation of the pyrethroid pesticide Cyflutrin by the halophilic Bacterium Photobacterium Ganghwense isolated from Coral Reef Ecosystem

Biodegradation of the pyrethroid pesticide Cyflutrin by the halophilic Bacterium Photobacterium Ganghwense isolated from Coral Reef Ecosyste

Hydroxyapatite Mineralization on the Calcium Chloride Blended Polyurethane Nanofiber via Biomimetic Method

Polyurethane nanofibers containing calcium chloride (CaCl2) were prepared via an electrospinning technique for the biomedical applications. Polyurethane nanofibers with different concentration of CaCl2 were electrospun, and their bioactivity evaluation was conducted by incubating in biomimetic simulated body fluid (SBF) solution. The morphology, structure and thermal properties of the polyurethane/CaCl2 composite nanofibers were characterized by means of scanning electron microscopy (SEM), field-emission scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, Fourier transform infrared spectroscopy and thermogravimetry. SEM images revealed that the CaCl2 salt incorporated homogeneously to form well-oriented nanofibers with smooth surface and uniform diameters along their lengths. The SBF incubation test confirmed the formation of apatite-like materials, exhibiting enhanced bioactive behavior of the polyurethane/CaCl2 composite nanofibers. This study demonstrated that the electrospun polyurethane containing CaCl2 composite nanofibers enhanced the in vitro bioactivity and supports the growth of apatite-like materials