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72.
P. Pratapa Mowli N. Venkata Subbayya B. Sathyanarayana Rao 《The International journal of environmental studies》2013,70(3):159-163
Air quality monitoring has become a very important task. Conventional methods for monitoring particulate matter are tedious and require considerable effort and manpower. This paper provides the results of investigations in developing an inexpensive technique to monitor air pollution due to particulate matter. Three plants (i) Pedilanthus tithymaloides, (ii) Pedilanthus varigatum and (iii) Nephrolepis exaltata are selected for the study. From the investigations, it is found that the inexpensive technique is very useful in developiong and under developed countries. It is also established that certain types of plants are quite effective in arresting particulate matter. 相似文献
73.
Chandra Sekhar Espenti Kummari Subba Venkata Krishna Rao Palakurthi Ramesh Akila Chandra Sekhar Kummara Madhusudana Rao 《IET nanobiotechnology / IET》2020,14(6):485
In this examination, we researched the advantages of DNA fragmentation and metallic nanoparticles well‐appointed with biomolecules. A novel interpretation of DNA damage by Silver Nano‐Clusters (AgNCs) which were developed by the utilization of green synthesis method was demonstrated. The green synthesis of AgNCs was accomplished by utilizing the leaf extract of Salacia mulbarica (SM). The preparation of SM‐AgNCs was developed by estimating surface plasmon resonance peak around 449 nm by using a UV–Visible spectrophotometer. The effect of phytochemicals in SM leaf extract on the development of stable SM‐AgNCs was confirmed by FTIR spectroscopy. The size of the fabricated SM‐AgNCs was estimated by dynamic light scattering and zeta‐sizer analysis and the morphology of the SM‐AgNCs was examined by transmission electron microscopy. The presence of clusters of Ag particles in the prepared SM‐AgNCs was recognized by energy dispersion X‐ray analysis. The results show that saponins, phytosterols, and phenolic compounds present in plant extract may play a great part in developing the SM‐AgNCs in their specialized particles. The succeeded SM‐AgNCs shows incredible anti‐bacterial action towards Escherichia coli and Bacillus subtilis. In‐light of the antibacterial study, these SM‐AgNCs were analyzed with calf thymus‐DNA and found significant damage to the strand of thymus‐DNA.Inspec keywords: visible spectra, surface plasmon resonance, transmission electron microscopy, DNA, nanofabrication, particle size, X‐ray chemical analysis, ultraviolet spectra, molecular biophysics, nanomedicine, microorganisms, nanoparticles, silver, X‐ray diffraction, antibacterial activity, Fourier transform infrared spectra, biomedical materialsOther keywords: stable SM‐AgNCs, silver nanoparticles, ct‐DNA damage, metallic nanoparticles, silver nanoclusters, Salacia mulbarica leaf extract, reactive oxygen species, DNA fragmentation, surface plasmon resonance, UV‐Visible spectrophotometer, Fourier transform infrared spectroscopy, dynamic light scattering, Zeta‐sizer analysis, transmission electron microscopy, energy dispersive X‐ray analysis, saponins, phytosterols, phenolic compounds, plant extract, Escherichia coli, Bacillus subtilis, Ag 相似文献
74.
Biswanath Mahanty Kannan Pakshirajan Veeranki Venkata Dasu 《Polycyclic Aromatic Compounds》2013,33(1):56-73
A novel method for preparation of pyrene encapsulated alginate beads for controlled release delivery of pyrene is reported in this study. Five different bead types that varied on the organic phase for pyrene delivery, presence or absence of polyvinyl alcohol (PVA) and boric acid treatment were prepared. Based on the pyrene release profile, silicone oil encapsulated in PVA-alginate bead was selected where encapsulation efficiency was more than 99% without any solvent leakage. Silicone oil encapsulation was further confirmed in microscopy observations. Pyrene release behavior from the beads was explained by a diffusion controlled first order release (R2 > 0.96). Reusability of this bead was demonstrated, where pyrene was loaded from an external medium in a non-destructive way. Application of the system was finally established in a biodegradation study using Mycobacterium frederiksbergense, where simultaneous release and removal of pyrene along with appearance of pyrene metabolites was observed. 相似文献
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In this work the role played by the presence of moisture and pH during ozone bleaching of grey cotton fabric and the design features of the ozone application chamber are reported. The results are explained with the help of a simplified model. The dyeing and resin finishing properties of ozone-bleached fabric are compared with those of hydrogen peroxide-bleached fabric. 相似文献
77.
This short note reports the results concerning electron paramagnetic resonance (EPR) and optical absorption spectra of Cu2+ ions doped in sodium potassium sulphate both at 300K and 77K. 相似文献
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Paramasivam Anandakumar Mallina Venkata Timmaraju Ramachandran Velmurugan 《应用聚合物科学杂志》2024,141(4):e54845
Design of automotive components with over-molded short/continuous fiber reinforced thermoplastic composites necessitates understanding of their behavior under extreme outdoor conditions. The short, quasi-isotropic and over-molded short/continuous glass fiber reinforced polypropylene (PP) composite specimens were prepared as per standard and immersed in water until equilibration to study their relative moisture absorption characteristics and consequent mechanical behavior. As the absorbed moisture mostly occupied the interface between fiber and matrix in laminated composite inserts and moisture absorption of short fiber composite core is insignificant, the moisture absorption of over-molded composites is just above 50% of that of laminated composites. The flexural, interlaminar shear and impact behavior of equilibrated composites is primarily governed by the quantum of imbibed moisture of composite materials. Optical analysis of failed moisture equilibrated over-molded specimens showed a marginal delamination between plies of the inserts without any perceptible damage within the short fiber composite similar to dry as molded specimens. 相似文献