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11.

Climate change issues are calling for advanced methods to produce materials and fuels in a carbon–neutral and circular way. For instance, biomass pyrolysis has been intensely investigated during the last years. Here we review the pyrolysis of algal and lignocellulosic biomass with focus on pyrolysis products and mechanisms, oil upgrading, combining pyrolysis and anaerobic digestion, economy, and life cycle assessment. Products include oil, gas, and biochar. Upgrading techniques comprise hot vapor filtration, solvent addition, emulsification, esterification and transesterification, hydrotreatment, steam reforming, and the use of supercritical fluids. We examined the economic viability in terms of profitability, internal rate of return, return on investment, carbon removal service, product pricing, and net present value. We also reviewed 20 recent studies of life cycle assessment. We found that the pyrolysis method highly influenced product yield, ranging from 9.07 to 40.59% for oil, from 10.1 to 41.25% for biochar, and from 11.93 to 28.16% for syngas. Feedstock type, pyrolytic temperature, heating rate, and reaction retention time were the main factors controlling the distribution of pyrolysis products. Pyrolysis mechanisms include bond breaking, cracking, polymerization and re-polymerization, and fragmentation. Biochar from residual forestry could sequester 2.74 tons of carbon dioxide equivalent per ton biochar when applied to the soil and has thus the potential to remove 0.2–2.75 gigatons of atmospheric carbon dioxide annually. The generation of biochar and bio-oil from the pyrolysis process is estimated to be economically feasible.

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12.
This study was carried out to investigate the effect of long-term exposure to benzo(a)pyrene (B(a)P) in mice. Hemogram, tumor markers, oxidative status, and B(a)P residues in liver tissue were evaluated. Sixty albino Swiss mice were randomly distributed equally into three groups; the control was given 0.1?mL corn oil once a week for 8 weeks. The other two groups were given 20 and 40?mg B(a)P per kg body weight once a week orally for the same period. B(a)P-treated mice suffered from depression and ascites, and macrocytic normochromic anemia was recorded at the 16th and 30th week. There was marked leukocytosis with lymphocytosis at the early stage of the experiment, followed by leukopenia, lymphopenia, and neutropenia at the end of the experiment. Monocytes and arginase activity were elevated throughout the experiment. Alpha feto-protein was detected only in the experimental groups in the 30th week of the experiment. A marked increase in lipid peroxides associated with a decrease in reduced glutathione and glutathione-S-transferase (GST) activity was observed in liver homogenate of the B(a)P-exposed animals. Residues of B(a)P were detected in liver tissue with a concentration parallel to the B(a)P dose level. In conclusion, B(a)P caused abnormal changes in the hemogram, evidence of tumor formation through B(a)P-induced oxidative stress, and it was accumulated in the liver tissue of mice.  相似文献   
13.
A simple, rapid analytical procedure for the quantification of emamectin benzoate in tomato was developed using high performance liquid chromatography with fluorescence detector (HPLC-FLD). Emamectin benzoate residues were extracted from tomato samples with n-hexane:ethyl acetate (1:1, v/v). The method involved derivatization using trifluoroacetic anhydride and 1-methylimidazole, prior to analysis by HPLC-FLD. Limit of quantification of this method was found to be 0.01 mg/kg, while limit of detection was 0.005 mg/kg. The dissipation of emamectin benzoate on tomato was studied, and half-life (t1/2) was estimated in a field study carried out at three different locations. Emamectin benzoate was sprayed on tomato at recommended dosage. Samples of tomato were collected at 0, 1, 3, 7, 10, and 15 days after treatment. The t1/2 of emamectin benzoate when applied at the recommended doses in tomato was approximately 2.5 days. The residue of emamectin benzoate reached below the maximal residue limit (MRL) 10 days after spraying at the tested dosage. Hence, a safe pre-harvest interval of 10 days is suggested before harvesting of tomato. This study would also be helpful for the Egypt government to establish the MRL of emamectin benzoate in tomatoes and provide guidance on the proper and safe use of this insecticide.  相似文献   
14.
Addition of plant residue into soils improves soil physiochemical properties and its fertility. Rapeseed residue is an emerging N source to paddy soils via rice-rape double-cropping practice. The objective of this study was to evaluate the effects of rapeseed residue and eggshell waste on chemical changes and enzyme activity in the rice paddy soil. The powdered eggshells at 0, 1, 3, and 5% were applied once to 7.0 kg paddy repacked soils in each pot treated with the rapeseed residue or the conventional N, P, and K fertilisers. Eight rice seedlings (Oriza sativa L. cv. Ilmibyeo) (40 days after sowing) were transplanted to the treated each pot. The contents of total C (TC) and N (TN), and organic matter (OM) were significantly increased in soils treated with the rapeseed residue compared to the N, P, and K fertilisers. With the addition of eggshell containing ~92% CaCO3, a considerable increase of soil pH was observed in soils treated with the rapeseed residue and the N, P, and K fertilisers, compared to the untreated soil. Activities of β-glucosidase, urease, and arylsulfatase enzymes were higher in soils treated with the rapeseed residue than soils treated with the N, P, and K fertilisers. The eggshell additions at 1, 3, and 5% into soils treated with the rapeseed residue increased enzyme activity mainly resulting from N mineralisation, whereas no change in enzyme activity was observed in the soils treated with the NPK fertiliser. The combined use of the rapeseed residue and the eggshells can be beneficial to improve soil environment.  相似文献   
15.
Journal of Polymers and the Environment - The aim of this study is to investigate the effect of fiber length and loading on physico-mechanical and flammability properties of Cyrtostachys renda (CR)...  相似文献   
16.
Environmental Science and Pollution Research - Epilepsy is one of the most common serious brain disorders, affecting about 1% of the population all over the world. Ginkgo biloba extract (GbE) and...  相似文献   
17.
Environmental Science and Pollution Research - Global warming is considered as the main environmental stress affecting ecosystems as well as physiological and biochemical characteristics, and...  相似文献   
18.
Environmental Science and Pollution Research - To identify level of job satisfaction among physicians at secondary and tertiary care levels. Random sample of 450 secondary and 523 tertiary care...  相似文献   
19.
Palm oil and its wastes as bioenergy sources: a comprehensive review   总被引:1,自引:0,他引:1  
Environmental Science and Pollution Research - Due to global warming and increasing price of fossil fuel, scientists all over the world have been trying to find reliable alternative fuels. One of...  相似文献   
20.
This study investigates adsorption-desorption and the leaching potential of glyphosate and aminomethylphosphonic acid (AMPA) in control and amended—addition of cow dung or rice husk ash—acidic Malaysian soil with high oxide mineral content. The addition of cow dung or rice husk ash increased the adsorptive removal of AMPA. The isotherm data of glyphosate and AMPA best fitted the Freundlich model. The constant Kf for glyphosate was high in the control soil (544.873 mg g?1) followed by soil with cow dung (482.451 mg g?1) then soil with rice husk ash (418.539 mg g?1). However, for AMPA, soil with cow dung was high (166.636 mg g?1) followed by soil with rice husk ash (137.570 mg g?1) then the control soil (48.446 mg g?1). The 1/n values for both glyphosate and AMPA adsorptions were <?1 indicating their strong affinity for adsorbents. Desorption of both glyphosate and AMPA occurred only in the control soil. The compounds were not detected in soils with added cow dung or rice husk ash. The addition of cow dung or rice husk ash increased glyphosate mobility. However, ground water ubiquity scores for both control and amended soils were <?2.8. This indicated glyphosate is a transitional herbicide; therefore, its leaching potential in the soil is low, despite the addition of cow dung or rice husk ash. Addition of these wastes decreased the mobility and leaching potential of AMPA. The addition of cow dung or rice husk ash could be beneficial in increasing adsorption and enhancing degradation of these compounds.  相似文献   
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