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-SDS- System: A highly Efficient Dual Catalytic Green System for Deprotection of Imines and in Situ Preparation of Bis(indolyl)alkanes from Indoles in Water  [PDF]
Parasa Hazarika,Pallab Pahari,Manash Jyoti Borah,Dilip Konwar
ISRN Organic Chemistry , 2012, DOI: 10.5402/2012/635835
Abstract: A novel catalytic system consisting of I2-SDS-H2O has been developed which cleaves 2,3-diaza-1,3-butadiene, 1-aza-1,3-butadienes, oximes and in presence of indoles in the medium uses the corresponding aldehyde products to produce bis(indolyl)alkanes in situ. This one pot simple and mild dual catalytic system works in water at room temperature under neutral conditions. 1. Introduction Using water as solvent in the organic reactions is one of the most important targets to organic chemists because of the easy availability, nontoxicity, and ecofriendly nature of the water [1–7]. In this endeavour, a number of chemical reactions such as Diels Alder, hetero Diels-Alder, 1,3-dipolar cycloaddition, oxidations, reductions, and others are performed successfully in water [1–3]. Also, it is reported that in few cases addition of the water increases the rate and the yield of a reaction and also enhances the enantioselectivity in a chiral synthesis [8]. But the main problems associated with water as a solvent is its poor ability to solubilise organic reactants and incapability to create anhydrous condition for moisture sensitive organic compounds and catalysts. To overcome the solubility problem, generally a surfactant is introduced to the reaction mixture. The surfactant, due to its hydrophobic and hydrophilic nature, forms micelles with water insoluble organic compounds and promote the desired reactions to occur inside the hydrophobic ambience of the micelle core [9, 10]. Cleavage of the C=N bonds is a very important transformation in organic synthesis as the C=N functionality is widely used to protect both the carbonyl and amines. There are a number of methods used for the cleavage of C=N bonds which include acidic reagents [11–13], oxidizing agents [14], metallic salts [15, 16], (PhSeO)2O [17], NaHSO3 [18], and others. Most of these methodologies suffer from serious drawbacks like involvement of strong Lewis and Bronsted acids, use of toxic and costly transition metals (i.e., Cr, Pd, Co), low temperature, longer reaction time, low yield, and difficulties in isolating the products. Therefore, development of efficient, mild and environment friendly reagents are always necessary. On the other hand, bisindoles are recently emerging as extremely important class of compounds because of their novel antibacterial and anticancer activities [19–21]. That is why a number of methodologies have also been postulated for the synthesis of bisindoles [22–29]. In our previous communications, we reported that surfactant- (SDS-) mediated cleavage of C=N bonds could be achieved with
A Review on Petroleum: Source, Uses, Processing, Products and the Environment  [PDF]
Onyenekenwa Cyprian Eneh
Journal of Applied Sciences , 2011,
Abstract: The review aimed at updating and enriching the literature on the meaning, uses, origin, formation, exploration, processing and products of petroleum, major petroleum producing countries, octane number, the petrochemical industry and petroleum and the environment. It used the table research method to synergise dated and current reports. Petroleum or rock oil probably originated from underground organic matter or due to chemical reactions in the sky thousands of million years ago. It consists mainly of a mixture of gaseous, liquid and solid hydrocarbons which are broken into various products by fractional distillation during refining. From the medieval times, petroleum has been a source of energy and recently predominated the synthesis of organic compounds. Petroleum exploration and use have some environmental challenges.
The nature and types of network relations in distribution of metallurgical products
LogForum , 2010,
Abstract: The article analyses the motives for establishing cooperation within a company supply network as division points in a supplies chain of metallurgical products. The division points were defined and identified at the level of service centres in the investigated chain. The analysis took into consideration various types of inter-organisational bonds, which are placed in the network relations classification matrix. The study concerns a complex distribution system. The analysed distribution network combines flows characteristic for both flexible and narrow supply chains.
Antioxidant capacity of different types of tea products
SM Karori, FN Wachira, JK Wanyoko, RM Ngure
African Journal of Biotechnology , 2007,
Abstract: In the present study, twelve different types of commercial tea samples were assayed to determine their phenolic composition and antioxidant activity. Reverse phase high performance liquid chromatography using a binary gradient system was used for the identification and quantification of individual catechins. Subsequently, total phenolic content was determined spectrophotometrically according to the Folin-ciocalteus method. Total theaflavins and thearubigins were also determined. The radical scavenging behavior of the polyphenols on 2,2-diphenyl-1-picrylhydrazyl radical (DPPH) was also studied spectrophotometrically. The results showed that total polyphenols, total catechins and antioxidant activity were significantly (P<0.05) different in the commercial tea samples. Green tea had the highest levels of catechins, total polyphenols and total antioxidant activity. White tea (silvery tip) a rare specialty type of tea was not significantly different from green tea. Statistical analysis showed an essential catechin content influence of the tea extracts on antioxidant activity. Epigallocatechin gallate (EGCG) was the most potent catechin and the most potent in antioxidant activity (r = 0.989***). Epigallocatechin (EGC) (r = 0.787, P<0.001), epicatechin (EC) + catechin (+C) and epicatechigallate (ECG) also showed significant (P<0.05) antioxidant activity. Black tea contained high levels of theaflavins and thearubigins, which accounted for most of the antioxidant potential in this type of tea product (r =0.930*** and r = 0.930*** respectively). These results suggest that conversion of catechins during black tea processing did not affect the free-radical potency of black tea. Gallic acid (GA) also showed significant(r = 0.530*) contribution to the antioxidant activity in black tea. Green, black and white tea products processed from Kenyan tea cultivars originally selected for black tea had significantly (P<0.05) higher antioxidant activity than green tea processed from tea cultivars from Japan and China. These results seem to suggest that the cultivar type is critical in determining the antioxidant potency of tea product and that black teas processed from suitable cultivars could be potent in antioxidant activity when compared to green teas.
Products of families of types in the C-systems defined by a universe category  [PDF]
Vladimir Voevodsky
Mathematics , 2015,
Abstract: We introduce the notion of a $(\Pi,\lambda)$-structure on a C-system and show that C-systems with $(\Pi,\lambda)$-structures are constructively equivalent to contextual categories with products of families of types. We then show how to construct $(\Pi,\lambda)$-structures on C-systems of the form $CC({\cal C},p)$ defined by a universe $p$ in a locally cartesian closed category $\cal C$ from a simple pull-back square based on $p$. In the last section we prove a theorem that asserts that our construction is functorial. This version introduces some changes compared to the previous one to ensure rigorous compatibility with arXiv:1409.7925v3.
Diversity Status and Sustainable Uses of Some Minor Forest Products in Ban Thung Soong Community Forest in Krabi Province, Thailand  [cached]
Hardawati Yahya,S. Bhumibhamon,D. Sookchaloem
Journal of Sustainable Development , 2009, DOI: 10.5539/jsd.v1n1p69
Abstract: The diversity status and sustainable uses of some Minor Forest Products in Ban Thung Soong Community Forest in Krabi Province were evaluated based on Important Value Index (IVI) analysis, utilizing method and quantitative ecological data based on local wisdom. The studies were found that at the highest level of 200-300 m altitude, the number of trees and total basal area was the highest than at level elevations of 0-100 m and 100-200 m from 12 stands (20x50 m2/stand). From IVI analysis, there were 65 species of plants found in Ban Thung Soong Community Forest (BTSCF). Analysis of IVI were found that the Xylia xylocarpa (Roxb.) Taub. var. kerrii (Craib & Hutch.) I.C.Nielsen shows the highest IVI with 22.37%. The highest percentage of relative density, relative frequencies and relative dominance were found in Homalium undulatum King with 7.50%, and 7.55% with Xylia xylocarpa (Roxb.) Taub. var. kerrii (Craib & Hutch.) I.C.Nielsen respectively. The numbers of species in BTSCF were 49+65 species ha-1 and comprises of number of trees, saplings and seedlings ha-1 were 4,697; 119,166 and 252,500 of trees ha-1 respectively. There were 49 species categorized as Minor Forest Products (MFPs) which include medicinal plants, edible plants, and non-edible plants.
Efficient Components on Livestock Products Export in Iran  [PDF]
Behnam Maleki, Farhad Mirzaei
Modern Economy (ME) , 2012, DOI: 10.4236/me.2012.38117
Abstract: Iran’s dependence on oil revenues has caused severe impact of commodity price fluctuations on the currency revenues and any reduction in export prices has led into a deficit in the country’s balance of payments. Accordingly, it was in the past years and especially the Second Development Plan that government included encouragement and reducing the country’s dependence on oil revenues in its agenda. The international agricultural exports, especially exports of live-stock and poultry country subdivision have a proper status due to its relative advantage. Therefore, in this study factors affecting the supply of exportable animal products are considered. For this purpose, factors affecting exports of live-stock products are studied by using Cointegration Analysis based on statistical intervals in 1984-2008. Experimental results showed that the value of income per capita importer countries of Iran and the real exchange rate had a positive effect on export demand and the added value and export price index had a negative impact on exports of livestock sector.
Antioxidant Properties of Rosemary and Its Potential Uses as Natural Antioxidant in Dairy Products—A Review  [PDF]
Ahmed S. Gad, Ahmed F. Sayd
Food and Nutrition Sciences (FNS) , 2015, DOI: 10.4236/fns.2015.61019
Abstract: Dairy products contain lipids rich in polyunsaturated fatty acids and their esters are easily oxidized by molecular oxygen over time. Deleterious changes in dairy products caused by lipid oxidation include not only loss of flavour or development of off-flavours, but also loss of colour, nutrient value, and the accumulation of compounds, which may be detrimental to the health of consumers. One of the most effective ways of retarding lipid oxidation in dairy products is to incorporate antioxidants. Sometimes synthetic phenolic antioxidant, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT) are used to delay this oxidation. Supplementation dairy products with natural antioxidants (polyphenolic compounds) are better using than synthetic antioxidant and could be potentially. The use of rosemary as natural antioxidant in dairy products can reduce the rate of lipid oxidation and hydrolysis besides may be beneficial in increasing the shelf life of these products. This supplementation will move these products into the functional food area under new category as healthy dairy products. This literature review covers the research that has focused on rosemary as antioxidant and anti-inflammatory agent that can inhibit the lipid oxidation and have health benefits by preventing carcinogens from binding to DNA, fight and stop pain. In this review, we survey the previous studies that were conducted on the application of rosemary extract as an antioxidant to extend the shelf life and to minimize nutritional losses of dairy product.
Organic carbon stocks in Mediterranean soil types under different land uses (Southern Spain)
M. Mu oz-Rojas, A. Jordán, L. M. Zavala, D. De la Rosa, S. K. Abd-Elmabod,M. Anaya-Romero
Solid Earth (SE) & Discussions (SED) , 2012, DOI: 10.5194/se-3-375-2012
Abstract: Soil C sequestration through changes in land use and management is one of the sustainable and long-term strategies to mitigate climate change. This research explores and quantifies the role of soil and land use as determinants of the ability of soils to store C along Mediterranean systems. Detailed studies of soil organic C (SOC) dynamics are necessary in order to identify factors determining fluctuations and intensity of changes. In this study, SOC contents from different soil and land use types have been investigated in Andalusia (Southern Spain). We have used soil information from different databases, as well as land use digital maps, climate databases and digital elevation models. The average SOC content for each soil control section (0–25, 25–50 and 50–75 cm) was determined and SOC stocks were calculated for each combination of soil and land use type, using soil and land cover maps. The total organic C stocks in soils of Andalusia is 415 Tg for the upper 75 cm, with average values ranging from 15.9 Mg C ha 1 (Solonchaks under "arable land") to 107.6 Mg C ha 1 (Fluvisols from "wetlands"). Up to 55% of SOC accumulates in the top 25 cm of soil (229.7 Tg). This research constitutes a preliminary assessment for modelling SOC stock under scenarios of land use and climate change.
Organic carbon stocks in Mediterranean soil types under different land uses (Southern Spain)  [PDF]
M. Mu?oz-Rojas,A. Jordán,L. M. Zavala,D. De la Rosa
Solid Earth Discussions , 2012, DOI: 10.5194/sed-4-1095-2012
Abstract: Soil C sequestration through changes in land use and management is one of the sustainable and long-term strategies to mitigate climate change. This research explores and quantifies the role of soil and land use as determinants of the ability of soils to store C along Mediterranean systems. Detailed studies of soil organic C (SOC) dynamics are necessary in order to identify factors determining fluctuations and intensity of changes. In this study, SOC contents from different soil and land use types have been investigated in Andalusia (S Spain). We have used soil information from different databases, as well as land use digital maps, climate databases and digital elevation models. The average SOC content for each soil control section (0–25, 25–50 and 50–75 cm) was determined and SOC stocks were calculated for each combination of soil and land use type, using soil and land cover maps. The total organic C stock in soils of Andalusia is 415 Tg for the upper 75 cm, with average values ranging from 15.9 Mg C ha 1 (Solonchaks under "arable land") to 107.6 Mg C ha 1 (Fluvisols from "wetlands"). Up to 55% of SOC accumulates in the top 25 cm of soil (229.7 Tg). This research constitutes a preliminary assessment for modelling SOC stock under scenarios of land use and climate change.
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