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51.
Journal of Polymers and the Environment - In this study, the nanohybrid drug carrier were synthesized by Pickering emulsion-templated encapsulation (PETE) method to control the...  相似文献   
52.
Journal of Polymers and the Environment - Modification of cellulose with silver nanoparticles produces various nanocomposites with significantly developed properties. This work aims to prepare a...  相似文献   
53.
The present investigation was conducted to determine the contamination status of arsenic (As), cadmium (Cd), and lead (Pb) in the wetland waters of Bhaluka in Bangladesh. Water samples were collected from 15 selected wetlands of Bhaluka region and analyzed using an atomic absorption spectrophotometer. Estimated results of three metals detected were As (7–80?µg?L?1), Pb (0–86?µg?L?1) and Cd (0–70?µg?L?1) in water samples in all wetlands. The level of As in all investigated wetlands (93%) was higher than that of WHO recommended permissible limit of drinking water except Alanga wetland. However, As levels were higher than that recommended for livestock water quality levels. Eighty-seven percent of the investigated wetlands showed lower content of Pb than WHO recommended permissible limit of drinking water, but two wetland waters (Dohuria-1 and Chowdhuri) were polluted with higher Pb levels. Sixty-seven percent of the investigated wetlands displayed higher levels of Cd than WHO recommended permissible limit in drinking water. Dissolved organic material showed no significant difference among the 15 investigated wetlands water, but total dissolved solids was significantly greater. The condition of the water of all wetlands was basic pH. All water samples were applied to linear regression equation and correlation coefficients where values showed no significant differences. Data demonstrate that the estimated high metal concentrations of these ponds may contribute to bioaccumulation within plants, food grains and shrimp.  相似文献   
54.
Because of the potential of significant geographic variation in the compositions of snake venoms, much insight can be gained by examining individuals originating from diverse locations, and detailed characterization of any species can only be done by including animals from the entire range. Pakistani N. naja (formerly N. naja karachiensis) venom was decomplexed by applying diverse techniques and found a concoction of proteins (a total of 43 venomous proteins comprising 11 super families) from 6 to 200 kilodaltons in size. Among them three finger toxins (58%), phosphoplipses A2 (19%), snake venom metalloproteinases (5%), l-amino acid oxidases (5%), helvepryns (3%), vespryns (2%), cobra venom factor (2%), 5′-nucleotidases (2%), venom nerve growth factor (2%), and Kunitz type serine protease inhibitor (2%) were included. It is the first report that this venom possesses significantly higher percentage of three finger toxins belonging to the cytotoxins (32% overall) and α‐neurotoxins (32% overall, predominately long chain neurotoxins, 24% overall) compared to N. naja from other geographic locations. Better understanding of intraspecific variations in venom can improve the development of location-specific anti-venoms. Furthermore, this pool of diverse toxins could potentially be a source of novel drug candidates for the treatment of muscarinic acetylcholine receptors mediated nervous disorders.  相似文献   
55.
Ali  Qaisar  Yaacob  Hakimah  Parveen  Shazia  Zaini  Zaki 《The Environmentalist》2021,41(4):616-632
Environment Systems and Decisions - Regardless of known as environment-friendly entities, Islamic banks indirectly impact the environment through their clients’ engagement and slow response...  相似文献   
56.
The role of exogenous spermine (0.25 mM Spm, a type of polyamine (PA) in reducing Cd uptake and alleviating Cd toxicity (containing 1 and 1.5 mM CdCl2 in the growing media) effects was studied in the mung bean (Vigna radiata L. cv. BARI Mung-2) plant. Exogenously applied Spm reduced Cd content, accumulation, and translocation in different plant parts. Increasing phytochelatin content, exogenous Spm reduced Cd accumulation and translocation. Spm application reduced the Cd-induced oxidative damage which was reflected from the reduction of H2O2 content, O2 ?– generation rate, lipoxygenase (LOX) activity, and lipid peroxidation level and also reflected from the reduction of spots of H2O2 and O2 ?– from mung bean leaves (compared to control treatment). Spm pretreatment increased non-enzymatic antioxidant contents (ascorbate, AsA, and glutathione, GSH) and activities of antioxidant enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione S-transferase (GST), monodehydroascorbate reductase (MDHAR), dehydroascorbate reductase (DHAR), and glutathione reductase (GR) which reduced oxidative stress. The cytotoxicity of methylglyoxal (MG) is also reduced by exogenous Spm because it enhanced glyoxalase system enzymes and components. Through osmoregulation, Spm maintained a better water status of Cd-affected mung bean seedlings. Spm prevented the chl damage and increased its content. Exogenous Spm also modulated the endogenous free PAs level which might have the roles in improving physiological processes including antioxidant capacity, osmoregulation, and Cd and MG detoxification capacity. The overall Spm-induced tolerance of mung bean seedlings to Cd toxicity was reflected through improved growth of mung bean seedlings.  相似文献   
57.
58.
Over the last few decades, electrostatic precipitators (ESPs) have emerged as effective air pollution control devices for treating coal-fired power plant exhausts. Among the components of the ESP, the discharge electrodes are extremely important in determining the collection efficiency of the ESP. Typically, in wet ESPs, the discharge electrodes used must be made of corrosion-resistant alloys, which makes them extremely expensive and heavy. Hybrid composite discharge electrodes have the potential to be lightweight and corrosion-resistant substitute for traditional metal alloy electrodes used in wet ESPs. In this experimental study, a novel hybrid composite electrode (recently patented at Ohio University) is presented as a substitute for traditional metal electrodes in wet ESPs. The samples of hybrid electrodes were fabricated by using carbon fiber composites, combined with metal mesh, in the shape of a long and thin tape. The electrode’s electrical response was evaluated in open atmospheric conditions, while connected to a transformer-rectifier unit to generate a corona current at voltages exceeding 50 kV. Results of these hybrid electrodes were compared with traditional metal electrodes. The hybrid composite discharge electrode produced a uniform corona at comparable power levels to that of metal electrodes, with additional advantages of being compact, lightweight, and highly corrosion resistant. In addition, hybrid composite electrodes exhibited lower corona onset voltage as compared with metal electrodes. The preliminary experimental data are encouraging and show significant potential for this new inexpensive hybrid electrode to replace metal electrodes in wet ESPs, providing comparable (and in some cases exceeding) collection efficiencies with lower ozone generation.

Implications: The newly invented hybrid composite electrode (HCE) performance was evaluated through experimentation with conventional metal electrodes. The HCE performance was comparable to the metal electrodes. The HCE also exhibited uniform corona fields and steady power while maintaining similar and in some cases superior electrical performance as compared with metal electrodes and thus shows a significant potential to substitute metal electrodes in wet ESP systems.  相似文献   

59.

Amethopterin is used as a chemotherapeutic agent, and its antioxidant activity is used to treat many cancer types. This study aimed to study the ameliorating effect of L-carnitine against amethopterin-induced cardiac injury and oxidative stress in male rats. Sixty male albino rats were equally divided into six groups; the first and second groups were the control and L-carnitine groups, respectively, while the third group was treated with amethopterin rat group; the fourth and fifth groups were co-treated and post-treated with amethopterin rat with L-carnitine, respectively, and the sixth group was self-treated with amethopterin rat group. Cholesterol, triglycerides, low-density lipoprotein (LDL), glutathione, and total protein levels in amethopterin group showed a significant decrease when compared with control group, while high-density lipoprotein (HDL), glutamic oxaloacetic transaminase (GOT), malondialdehyde (MDA), catalase, and nitric oxide (NO) levels in amethopterin group showed a significant increase when compared with control group. Cholesterol, triglycerides, LDL, GOT, MDA, and catalase levels in the self-treated group showed a significant increase when compared with amethopterin group, while glutathione, total protein, and NO levels in the self-treated group showed significant decrease when compared with amethopterin group. Many of abnormalities as moderate hydrophobic changes of myofibrillar structure with striations, myocardial atrophy, cytoplasmic vacuoles, edema, and leukocyte infiltration were detected in cardiac tissues in amethopterin rat group. A significant increase of the apoptotic protein p53 and CD68 immunoreactivity, despite a significant decrease in the antiapoptotic Bcl–2 proteins after amethopterin injection when compared with control group, was observed. Treatment (co and post) with L-carnitine improved the biochemical, histopathological, and immunohistochemical alterations in the heart treated with amethopterin.

  相似文献   
60.
Water samples taken from selected industrial drainages and receiving streams in and around Islamabad, Pakistan, during the summers of 1987 to 1990 showed disturbances in pH and low oxygen levels. Selected metals (Fe, Pb, Zn, Cd, Cu, Ni, Hg) were higher in all effluents than in receiving waters. Static bioassays of the undiluted industrial effluents from three sites caused 100% mortality in carp during the first 24 hrs. Fishes also suffered 30 to 60% mortality when exposed to other undiluted industrial effluents and some mortality when industrial effluents were diluted by 50%.  相似文献   
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