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11.
Rai V Kakkar P Singh J Misra C Kumar S Mehrotra S 《Environmental monitoring and assessment》2008,143(1-3):273-277
Herbal formulations are getting popularity throughout the world and commercialized extensively for various medicinal properties. WHO has emphasized the need for quality assurance of herbal products, including testing of heavy metals and pesticides residues. 'Dashmoola', a popular herbal formulation, with immunomodulator and febrifugal properties, consists of ten single root drugs. In view of WHO guidelines, single herbal drugs used in 'Dashmoola', were collected from different places of India for testing heavy metals and persistent pesticides residue. Although use of roots in 'Dashmoola' is prescribed in original ayurvedic literature but now many pharmacies use stem in place of roots. Therefore, in the present study both roots and stems were selected for estimation of six heavy metals namely arsenic (As), mercury (Hg), lead (Pb), cadmium (Cd), chromium (Cr) and nickel (Ni). Apart from these, the organochlorine pesticides residue viz. different metabolites of DDT, DDE, isomers of HCH and alpha-endosulfan were checked in total 40 samples of single crude drugs. Heavy metals except Hg, were present in most of the samples. In few samples Pb and Cd concentration were beyond the WHO permissible limits. Although alpha-HCH and gamma-HCH were present in almost all the samples, but other pesticides were not detected in these samples. DDT and DDE were found only in two samples. 相似文献
12.
Satyanarayan S Ramakant Satyanarayan A 《Journal of environmental science and health. Part. B》2005,40(3):397-412
Freshwater fish Cyprinus carpio was selected for the study of bioaccumulation of organochlorinated pesticides in tissues like gills, muscle, intestine, kidney, and liver in a continuous fed system. The pesticides used were Aldrin, Dieldrin, BHC, and DDT. The bioaccumulation of Dieldrin was maximum of 85.0 microg g(-1) wet weight in liver tissue while minimum of 7.30 microg g(-1) wet weight for DDT at 30 days exposure time. Bioconcentration factor (BCF) has followed the same trend in liver tissue for Dieldrin and DDT. The rate of bioaccumulation was found to be maximum of 4.3879 microg g(-1) wet weight in liver tissue and minimum of 0.0021 microg g(-1) wet weight in gill tissue for 30 days exposure. As evidenced by the increasing values of BCF, pesticide uptake also showed increased trend with the increase in exposure time. A high correlation coefficient ranging between 0.7247 and 0.9616 between the pesticide concentration and exposure time was observed. Based on actual BCF values, log Kow were calculated and the values are well within the reported values of 6.5 indicating efficient relationship between BCF and log Kow because beyond the 6.5 the bioconcentration levels off. 相似文献
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14.
Olayide O. Fabunmi Lope G. Tabil Satyanarayan Panigrahi Peter R. Chang 《Journal of Polymers and the Environment》2011,19(4):841-848
This study focused on improving the material properties of pea thermoplastic starch (TPS) with polycaprolactone (PCL) and
flax fiber. Accordingly, composites of glycerol-plasticized pea starch, polycaprolactone, and flax fiber were prepared through
solid-phase compounding and compression-molding. The specimens were characterized through scanning electron microscopy, tensile
test, moisture absorption test, and differential scanning calorimetry. Morphological studies of the tensile fracture surfaces
revealed poor TPS-PCL interfacial interaction and limited TPS-flax fiber interfacial bonding. The composites showed significant
improvements in tensile strength with reduced moisture absorption capability essentially due to the hydrophobicity of PCL.
Individual components of the composites retained their respective thermal properties, an indication of thermodynamic immiscibility. 相似文献
15.
Majid Soleimani Lope Tabil Satyanarayan Panigrahi Anthony Opoku 《Journal of Polymers and the Environment》2008,16(1):74-82
Recently, investigations have been conducted on the use of natural fibers as reinforcement in low-melting point thermoplastics
to improve mechanical properties of composites. However, due to some limitations of natural fibers, composite formulation
and processing parameters must be controlled to produce a product with improved properties. This study was conducted to investigate
the influence of flax fiber loading, use of compatibilizer and pretreatment on physical and mechanical properties of compression-molded
composite. In this study, untreated and treated (sodium hydroxide-treated and mild-bleached flax fibers) fibers at 15% and
30% of the total product mass were used in formulations. To investigate the effect of compatibilizer on product properties,
maleic anhydride grafted polypropylene (MAPP) was added at 5% by mass in the formulations. After extrusion of composites formulations,
they were formed using compression molding. Results indicated that using flax fiber in composites without pretreatment and
compatibilizer could result into products with inferior physical and mechanical properties; this could be compensated by the
use of a compatibilizer. However, the use of compatibilizer had some negative effects on some other physical properties like
color and melt flow index (MFI). 相似文献
16.
Srivastava SK Rai V Srivastava M Rawat AK Mehrotra S 《Environmental monitoring and assessment》2006,116(1-3):315-320
Popularity of herbal drugs is increasing all over the world because of lesser side effects as compared to synthetic drugs.
Besides, it costs less and easily available to poor people particularly in developing countries. But quality assurance of
herbal drugs is very necessary prior to its use. Because in today's polluted environment, even herbal drugs are not safe.
Berberis spp. is very important medicinal plant, having various medicinal properties. It is also included in Indian and British pharmacopoeias.
Its demand is quite high in herbal drug market. So, to check the quality of market samples of this drug, ten different samples
were procured from different drug markets of India for heavy metal estimation. Besides, genuine samples of four species of
Berberis viz. B. aristata, B. chitria, B. lycium, B. asiatica were also collected from natural habitats to compare heavy metal concentration in both market and genuine samples. It was found that market samples were much more contaminated than genuine samples. Lead (Pb) concentration is far beyond
from WHO permissible limit (10 ppm) for herbal drugs, reaching to maximum 49.75 ppm in Amritsar market sample. Likewise, concentration
of all other metals like Cd, Cr and Ni were also very high in market samples as compared to genuine samples. 相似文献