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Molecular characterization of cyanobacterial diversity in Lake Gregory, Sri Lanka 被引量:3
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作者 Dhammika MAGANA-ARACHCHI Rasika WANIGATUNGE Madhushankha LIYANAGE 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第4期898-904,共7页
Eutrophication or the process of nutrient enrichment of stagnant waters due to excessive use of fertilizer is becoming a critical issue worldwide. Lake Gregory, an artificial lake situated in Nuwara Eliya, Sri Lanka w... Eutrophication or the process of nutrient enrichment of stagnant waters due to excessive use of fertilizer is becoming a critical issue worldwide. Lake Gregory, an artificial lake situated in Nuwara Eliya, Sri Lanka was once a very attractive landscape feature and recreational area attracting a large number of visitors. Rapid urbanization in surrounding areas and the consequent intensification of agricultural and industrial activities led to eutrophication and siltation in the lake. Present study was conducted to detect cyanobacterial diversity and their ability to produce hepatotoxic microcystins using polymerase chain reaction (PCR)-based techniques. Twenty five water samples (surface and bottom) were collected from the lake and total nitrogen and total carbon were estimated. Cyanobacterial cultures were grown in appropriate media and microscopic observations were used to determine the morphological diversity of cyanobacteria isolated from different sites. Genomic DNA was isolated and purified from cyanobacteria using Boom's method. DNA samples were analyzed by PCR with oligonucleotide primers for 16S rRNA gene and mcyA gene of the operon that encodes a microcystin synthetase. The 16S rRNA gene sequences revealed the presences of cyanobacteria belong to Synechococcus sp., Microcystis aeruginosa, Calothrix sp., Leptolyngbya sp., Limnothrix sp., order Oscillatoriales and order Chroococcales. The sequences obtained from this study were deposited in the database under the accession numbers (GenBank: GU368104-GU368116). PCR amplification of mcyA primers indicated the potential for toxin formation of isolated M. aeruginosa from Lake Gregory. This preliminary study shows that the Lake Gregory is under the potential risk of cyanobacterial toxicity. Clearly more work is needed to extend this finding and clarify if other cyanobacterial isolates have genetic potential to produce microcystin since this lake is utilized for recreational activities. 展开更多
关键词 斯里兰卡 多样性 蓝藻 分子特征 RRNA基因序列 水体富营养化 基因组DNA 微囊藻毒素
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Two-Thirds Law of Nitrogen Mineralization Under Undisturbed Soil Conditions:A New Theory 被引量:2
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作者 G.SENEVIRATNE 《Pedosphere》 SCIE CAS CSCD 2008年第2期149-153,共5页
它在文学被报导全球性,在滋养的来源的仅仅大约三分之二 N 在在没受到干扰的条件下面的土壤对植物和微生物可得到。现在的学习探索这现象并且建议一个新理论解释这。从微地点来源的 NH+4 的散开这里被考虑并且分析了为一土壤系统毛状... 它在文学被报导全球性,在滋养的来源的仅仅大约三分之二 N 在在没受到干扰的条件下面的土壤对植物和微生物可得到。现在的学习探索这现象并且建议一个新理论解释这。从微地点来源的 NH+4 的散开这里被考虑并且分析了为一土壤系统毛状。从滋养的来源传播了,被发现 68% NH+4 开始在滋养的来源的最近被保存,而,留下 32% 被传播离开滋养的来源并且可能在非可交换的不能生活的水池使不能调动或输。开始在微地点附近被保留了的 NH+4 逐渐地被释放到矿物质水池。因此,免除微地点的大约三分之二 NH+4 在土壤对植物和微生物仅仅可得到。这是为植物和微生物引起的可获得性的滋养的保存的通用、自然机制。理论在推荐器官的 N 授精 in the forms of 或矿物质来源到越过各种各样的土壤质地,进一步的研究为被需要种的植物有重要含意和应用。从这个理论的任何偏差能主要被归因于各种各样的骚乱到土壤;例如,机械骚乱,沥滤的营养素,和在 pH 和土壤的变化动物区系的活动。这个理论可以适用于另外的元素在没受到干扰的条件下面在土壤使矿物化,它必须在未来研究被调查。 展开更多
关键词 土壤 矿化 肥料
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Distinct metamorphic evolution of alternating silica-saturated and silica-deficient microdomains within garnet in ultrahigh-temperature granulites: An example from Sri Lanka 被引量:1
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作者 P.L.Dharmapriya Sanjeewa P.K.Malaviarachchi +5 位作者 Leo M.Kriegsman K.Sajeev Andrea Galli Y.Osanai N.D.Subasinghe C.B.Dissanayake 《Geoscience Frontiers》 SCIE CAS CSCD 2017年第5期1115-1133,共19页
Here we report the occurrence of garnet porphyroblasts that have overgrown alternating silica-saturated and silica deficient microdomains via different mineral reactions. The samples were collected from ultrahigh-temp... Here we report the occurrence of garnet porphyroblasts that have overgrown alternating silica-saturated and silica deficient microdomains via different mineral reactions. The samples were collected from ultrahigh-temperature(UHT) metapelites in the Highland Complex, Sri Lanka. In some of the metapelites, garnet crystals have cores formed via a dehydration reaction, which had taken place at silicasaturated microdomains and mantle to rim areas formed via a dehydration reaction at silica-deficient microdomains. In contrast, some other garnets in the same rock cores had formed via a dehydration reaction which occurred at silica-deficient microdomains while mantle to rim areas formed via a dehydration reaction at silica-saturated microdomains. Based on the textural observations, we conclude that the studied garnets have grown across different effective bulk compositional microdomains during the prograde evolution. These microdomains could represent heterogeneous compositional layers(paleobedding/laminations) in the precursor sediments or differentiated crenulation cleavages that existed during prograde metamorphism. UHT metamorphism associated with strong ductile deformation, metamorphic differentiation and crystallization of locally produced melt may have obliterated the evidence for such microdomains in the matrix. The lack of significant compositional zoning in garnet probably due to self-diffusion during UHT metamorphism had left mineral inclusions as the sole evidence for earlier microdomains with contrasting chemistry. 展开更多
关键词 UHT METAPELITES GARNET MICRODOMAINS Highland Complex Sri Lanka
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Production of small molecules by an endophytic fungus,Neofusicoccum parvum from the fruits of Elaeocarpus serratus 被引量:1
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作者 Dilhara Dissanayake NSavitri Kumar +3 位作者 NKBAdikaram Lalith Jayasinghe Hiroshi Araya Yoshinori Fujimoto 《Asian Journal of Traditional Medicines》 CAS 2020年第2期47-54,共8页
Neofusicoccum parvum,an endophytic fungus isolated from Elaeocarpus serratus(Ceylon Olive;family Elaeocarpaceae),was grown for 3 weeks in potato dextrose broth.Chromatographic separation of the ethyl acetate extracts ... Neofusicoccum parvum,an endophytic fungus isolated from Elaeocarpus serratus(Ceylon Olive;family Elaeocarpaceae),was grown for 3 weeks in potato dextrose broth.Chromatographic separation of the ethyl acetate extracts from the culture filtrate and mycelium over silica gel,Sephadex LH-20 and preparative thin layer chromatography furnished(R)-7-hydroxymellein(1),(3R,4R)-4-hydroxymellein(2),(3R,4S)-4-hydroxymellein(3),(R)-5-hydroxymellein(4),(R)-mellein(5),(3R,4R)-4,7-dihydroxymellein(6),(6R,7S)-dia-asperlin(7),CJ-14445(8)and 13,14,15,16-tetranorlabd-7-ene-19,6β:12,17-diolide(9).The structures of known compounds 1–9 were determined by spectroscopic methods and comparison with reported data.This is the first report of the isolation of an endophytic fungus from E.serratus,and the isolation of compounds 1,4,6,8 and 9 from N.parvum.It is important to note that compounds 1–7 are small molecules with an oxygen heterocyclic ring system.These compounds can be used as starting materials in the synthesis of pharmaceutically important large molecules with oxygen heterocyles. 展开更多
关键词 Neofusicoccum PARVUM ELAEOCARPUS serratus ENDOPHYTIC FUNGI secondary METABOLITES dihydroisocoumarines
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Analytical Signal and Reduction to Pole Interpretation of Total Magnetic Field Data at Eppawala Phosphate Deposit 被引量:1
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作者 N. D. Subasinghe W. K. D. G. D. R. Charles S. N. De Silva 《Journal of Geoscience and Environment Protection》 2014年第3期181-189,共9页
A magnetic survey was carried out to find out the possibilities of demarcating a phosphate deposit from the surrounding country rocks. It is a well-established fact that the magnetic mapping can be utilised to investi... A magnetic survey was carried out to find out the possibilities of demarcating a phosphate deposit from the surrounding country rocks. It is a well-established fact that the magnetic mapping can be utilised to investigate the subsurface objects, materials or different rock types based on their magnetic properties. Those rocks with ferro-magnetic minerals such as magnetite generate magnetic anomalies which in turn help to investigate the subsurface occurrence of mineral deposits. An economic phosphate deposit in Sri Lanka, known as Eppawala Phosphate deposit was selected for this study. The deposit was formed as an accumulation of secondary products of an apatite-rich carbonatite. Due to weathering of iron-rich carbonatite, magnetite and its derivatives are intimately bound with the said deposit. Therefore, the magnetic signature of the phosphate body is different to that of the surrounding country rocks. Despite some studies on different aspects of the deposit, subsurface extents of the ore body are so far not adequately studied. Therefore, this study was conducted to identify the boundaries of the phosphate body. The study was carried over an area of 12 km2 5 km north from the current mining site and survey was conducted. GSM-19 Overhouser system with integrated GPS was used to collect field data. Magnetic anomalies were plotted using a predefined grid. The maximum positive and negative anomalies encountered in the survey area are 690 nT and 829 nT respectively. This study showed that magnetite is not distributed evenly in the area and the deposit extended along the north south direction. Further, processing of analytical signal using the anomalies showed that the carbonatite occurs as a continuous body trending in North South direction. Low magnetic latitudes magnetic data interpretation is difficult because the vector nature of the magnetic field. Therefore, “reduction to pole” concept and “analytical signal concept” were used for the data analysis. Reduction to pole map and analytical signal map are comparatively similar and the change of declination value has no significant effect on the map of reduction to pole. 展开更多
关键词 MAGNETIC ANOMALY ANALYTICAL SIGNAL REDUCTION to POLE
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Polymer Sensitized Quasi Solid-State Photovoltaic Cells Using Derivatives of Polythiophene
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作者 G.K.R.Senadeera J.M.R.C.Fernando 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2006年第6期811-816,共6页
Substituted thiophene sensitized, nanocrystalline TiO2-based quasi solid-state solar cells were fabricated by using either poly (3-thiophene acetic acid) (P3TAA) or a copolymer with poly (3-thiophene acetic acid... Substituted thiophene sensitized, nanocrystalline TiO2-based quasi solid-state solar cells were fabricated by using either poly (3-thiophene acetic acid) (P3TAA) or a copolymer with poly (3-thiophene acetic acid)-poly (hexyl thiophene) (P3TAA-PHT) polymers and copper iodide (Cul) as a hole conducting material together with an ionic liquid 1-ethyl-3-methylimidazolium bis (trifluoromethylsulfonyl) amide and lithium bis (triflu- oromethanesulfone) imide as additives for charge transport promotion. Dramatic enhancements in the cell performances were observed with the additives in Cul. While the cell sensitized with P3TAA generated a short-circuit photocurrent of -1.45 mA.cm^-2, an open-circuit photovoltage of -345 mV with a total power conversion efficiency of -0.3% under simulated full sunlight of 100 mW-cm^-2 (air mass: 1.5), the cell sensitized with copolymer P3TAA-PHT delivered -0.25% efficiency under the same conditions with -1.23 mA-cm^-2 as photocurrent and -371 mV as photovoltage. 展开更多
关键词 Solar cells POLYMERS Titanium dioxide
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Morphological characterization, antioxidant capacity and diversity of Syzygium cumini trees from Sri Lanka
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作者 Prasajith Kapila Dissanayake Wekumbure Gedara Chandima Wekumbura +1 位作者 Alge Watage Wijeratne Douglas Siril Abeywickrama Wijesundara 《Horticultural Plant Journal》 SCIE CSCD 2022年第1期53-67,共15页
Syzygium cumini(L.)Skeels(Madan)is widely distributed in South Asian countries,including Sri Lanka,where it was naturally found.There were only few studies reported on S.cumini for its values and other benefits in Sri... Syzygium cumini(L.)Skeels(Madan)is widely distributed in South Asian countries,including Sri Lanka,where it was naturally found.There were only few studies reported on S.cumini for its values and other benefits in Sri Lanka.This study focuses on morphological characterization and the diversity of S.cumini trees in seven locations of Sri Lanka.Data were collected on different morphological traits.Leaf,flower and fruit morphology showed significant differences among locations.Further,trees from Batticaloa region showed different morphology,which would potentially open a different avenue for further study to trace different cultivars across the country.Results of the diversity index and multivariate analyses indicated high diversity in morphology and antioxidant capacity of trees.The variables such as leaf area,inter-nodal length,petiole length,anther length,filament length,fruit size and pericarp thickness could be suitable candidates to investigate the morphological variation of S.cumini any further.Antioxidant capacity studies also showed significant differences among locations and trees.Fruit hue angle was positively correlated to antioxidant capacities.Finding of this study concluded that the wide distribution of S.cumini trees throughout Sri Lanka in different geographical locations showed high diversity in leaf,flower and fruit morphology together with antioxidant capacity. 展开更多
关键词 Syzygium cumini Morphological diversity Antioxidant capacity Sri Lanka
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Engineering Microbial Biofilms for Improved Productivity of Biochemicals Important in Restoration of Degraded Ecosystems
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作者 Mahesh Premarathna Thilini Rathnathilaka +1 位作者 Gamini Seneviratne Sumedha Madawala 《Advances in Bioscience and Biotechnology》 2022年第3期145-158,共14页
Biofilms are being engineered in-vitro to produce numerous commodities like biofertilizers, pharmaceuticals, biofuels and electricity, the efficacies of which rely on the biochemicals secreted by the biofilms i.e. ext... Biofilms are being engineered in-vitro to produce numerous commodities like biofertilizers, pharmaceuticals, biofuels and electricity, the efficacies of which rely on the biochemicals secreted by the biofilms i.e. extracellular polymeric substances (EPS). It has been shown that once EPS-biochemicals of developed biofilms are applied to an ecosystem, they can restore degraded complex ecosystem networks for improved ecosystem functioning and sustainability. Identification of the EPS biochemicals and understanding their contributions to the network interactions in particular, are at initial stage. In the present study, using Aspergillus niger, Nostoc sp., and gram (-) Stenotrophomonas maltophilia & gram (+) Bacillus subtilis as test fungal (F), cyanobacterial (C), and bacterial (B) counterparts, respectively we analyzed morphology and biochemical parameters of fungal-bacterial (FBBs), fungal-cyanobacterial (FCBs), cyanobacterial-bacterial (CBBs), and fungal-cyanobacterial-bacterial biofilms (FCBBs). Results revealed that the FCBBs produced the highest concentrations of lipids, proteins, and polysaccharides whereas FBBs generated the highest diversity of biochemicals. Bacterial type (i.e. gram + or -) and microbial composition in the biofilm affected the biochemical production. Ecologically and industrially important diverse biochemicals which are used individually as medicines, bioremediating agents and industrial chemicals in human society with certain adverse and beneficial effects were detected in the biofilm-EPS. However, in the nature, simultaneous action of those diverse biochemicals applied as biofertilizers has already shown a huge potential to restore the entire agroecosystems degraded due to farmers’ detrimental practices. This striking difference in utilization of the biochemicals and their enhanced effect when they act simultaneously needs further investigations for their better applications. 展开更多
关键词 Biochemicals Biofilms Ecosystem Restoration Extracellular Polymeric Substances
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Secondary Metabolites Produced by an Endophytic Fungus Pestalotiopsis microspora 被引量:4
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作者 G.R.Nalin Rathnayake N.Savitri Kumar +2 位作者 Lalith Jayasinghe Hiroshi Araya Yoshinori Fujimoto 《Natural Products and Bioprospecting》 CAS 2019年第6期411-417,共7页
An endophytic fungus Pestalotiopsis microspora isolated from the fruits of Manilkara zapota was cultured in potato dextrose broth media.Chromatographic separation of the EtOAc extract of the broth and mycelium led to ... An endophytic fungus Pestalotiopsis microspora isolated from the fruits of Manilkara zapota was cultured in potato dextrose broth media.Chromatographic separation of the EtOAc extract of the broth and mycelium led to the isolation of a new azaphilonoid named pitholide E(1),in addition to previously identified pitholide B(2),pitholide D(3),pestalotin(LL-P880α)(4),PC-2(5),LL-P880β(6),tyrosol(7)and 4-oxo-4H-pyran-3-acetic acid(8).An endophytic fungus P.microspora from M.zapota and the isolation of compounds 1-5,7 and 8 from P.microspora are reported here for the first time. 展开更多
关键词 Pestalotiopsis microspora Manilkara zapota ENDOPHYTE Pitholide E Pestalotin
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Secondary metabolites from an endophytic fungus Aspergillus fumigatus from Solanum insanum L.
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作者 Vindya Kanthi Munasinghe N.Savitri Kumar +3 位作者 Nimal Adikaram Lalith Jayasinghe Hiroshi Araya Yoshinori Fujimoto 《Asian Journal of Traditional Medicines》 CAS 2021年第2期76-82,共7页
An endophytic fungus Aspergillus fumigatus,isolated from the fruits of Solanum insanum L.,was cultured in potato dextrose broth medium.Chromatographic separation of the EtOAc extract led to the isolation of six second... An endophytic fungus Aspergillus fumigatus,isolated from the fruits of Solanum insanum L.,was cultured in potato dextrose broth medium.Chromatographic separation of the EtOAc extract led to the isolation of six secondary metabolites,identified as pseurotin A(1),fumigaclavine C(2),monomethylsulochrin(3),trypacidin(4),fumiquinazoline C(5)and guignasulfide(6)by spectral means.Compounds 2 and 3 showed brine shrimp toxicity with IC50 values of 147 and 74.2μM,respectively,while compounds 4 and 5 showed slight inhibition on the growth of fungal pathogen Cladosporium cladosporioides.This is the first report of the isolation of guignasulfide(6)from A.fumigatus,which has been previously isolated only from an endophytic fungus Guignardia sp. 展开更多
关键词 Aspergillus fumigatus Endophytic fungi Solanum insanum Guignasulfide
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Carbon Sequestration in Tropical Forest Stands: Its Control by Plant, Soil and Climatic Factors
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作者 K. A. J. M. Kuruppuarachchi Gamini Seneviratne Buddhika D. Madurapperuma 《Open Journal of Forestry》 2016年第2期59-71,共13页
This study investigated the relationships amongst floristic, soil and climatic parameters and their control on carbon sequestration (CS) in two selected forest stands of Sri Lanka. Representative sampling sites were s... This study investigated the relationships amongst floristic, soil and climatic parameters and their control on carbon sequestration (CS) in two selected forest stands of Sri Lanka. Representative sampling sites were selected from the dry zone (Sigiriya forest sanctuary) and the wet zone (Udawattakele forest reserve) of Sri Lanka. Litter and soil samples were collected from each sampling site randomly in monthly intervals to cover an annual cycle. Plant biomass carbon stocks were calculated using standard biomass equations. Soil carbon stocks were determined by chemical oxidation and loss on ignition (LOI) methods. Principle Factor Analysis and multiple regression were used to quantify the relationships among the plants, soil and climatic variables. Plant biomass carbon stocks of the forests were governed by labile and stable C fractions, soil moisture, and plant diversity. The soil fulvic fraction acts as a focal point of interacting the variables such as soil N, free litter fraction (FLF) and humic fraction. During dry period in the dry zone forest, CS was governed by maximum relative humidity through an atmosphere-floor litter-soil continuum. Air temperature and FLF play a vital role in determining soil N. In addition, MacIntosh distance (U) diversity index showed a significant positive relationship with soil N. The dry zone forests are seen to be more climatic sensitive and vulnerable than the wet zone forests in Sri Lanka due to influence of more climatic parameters that govern the soil organic carbon fractions. 展开更多
关键词 Tropical Forests Carbon Sequestration Soil Organic Carbon
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Giant Comet C/2014 UN271 (Bernardinelli-Bernstein) Provides New Evidence for Cometary Panspermia
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作者 N. Chandra Wickramasinghe 《International Journal of Astronomy and Astrophysics》 2022年第1期1-6,共6页
The discovery of a giant comet (C/2014 UN271) at a distance of 29 AU in October 2014 and the later discovery in September 2021 of a dramatic brightening episode offers an ideal opportunity for verifying the prediction... The discovery of a giant comet (C/2014 UN271) at a distance of 29 AU in October 2014 and the later discovery in September 2021 of a dramatic brightening episode offers an ideal opportunity for verifying the predictions of a “biological” comet. The eruptions of the comet at a heliocentric distance of 20 AU are plausibly explained as due to high pressure venting of the products of microbial metabolism in radioactively heated subsurface lakes. The standard non-biological model of comets is woefully inadequate to account for eruptions at such large distances from the sun where surface temperatures are as low as 60 K. 展开更多
关键词 Comets Cometary Activity Bacteria and Viruses PANSPERMIA
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Aging Effects of Organic and Inorganic Fertilizers on Phosphorus Fractionation in a Calcareous Sandy Loam Soil 被引量:12
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作者 Munir AHMAD Mahtab AHMAD +6 位作者 Ahmed H.EL-NAGGAR Adel R.A.USMAN Adel ABDULJABBAR Meththika VITHANAGE Jamal ELFAKI Abdulelah AL-FARAJ Mohammad I.AL-WABEL 《Pedosphere》 SCIE CAS CSCD 2018年第6期873-883,共11页
In most arid and semiarid soils, naturally occurring phosphorus(P) is a major yield-limiting plant nutrient. In this study, to investigate the effects of organic(OP) and inorganic P(IP) sources on P fractionation, a c... In most arid and semiarid soils, naturally occurring phosphorus(P) is a major yield-limiting plant nutrient. In this study, to investigate the effects of organic(OP) and inorganic P(IP) sources on P fractionation, a calcareous sandy loam alkaline soil was fertilized with OP and IP fertilizers at low(80 mg P kg^(-1) soil) and high(160 mg P kg^(-1) soil) application rates. Three combinations of OP and IP(i.e., 75% OP + 25% IP, 50% OP + 50% IP, and 25% OP + 75% IP) were applied at low and high application rates,respectively, followed by soil aging for 21 d. Soil samples were collected after 1, 2, 3, 7, and 21 d and subjected to sequential extraction to analyze soluble and exchangeable, Fe-and Al-bound, Ca-bound, and residual P fractions. The soluble and exchangeable P fraction significantly increased up to 24.3%, whereas the Ca-bound fraction decreased up to 40.7% in the soils receiving 75% OP + 25% IP and 50% OP + 50% IP, respectively, compared with the control(receiving no P fertilizer). However, the transformation of P fractions was influenced by aging time. Addition of P sources caused instant changes in different P fractions, which then tended to decline with aging time. Change in soil p H was the limiting factor in controlling P availability. At high application rate, the OP source significantly increased soil P availability compared with the IP source with soil aging. Depending on P fractionation, a proper combination of OP and IP fertilizers, as long-term slow and instant P-releasing sources for plant uptake, respectively, may be a sustainable strategy to meet crop P requirements in the arid and semiarid soils. 展开更多
关键词 PHOSPHORUS availability PHOSPHORUS FRACTION POULTRY MANURE sequential extraction SOIL pH
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Optimized pre-treatment of high strength food waste digestate by high content aluminum-nanocluster based magnetic coagulation 被引量:5
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作者 Tharindu Ritigala Hailu Demissie +9 位作者 Yanlin Chen Jiaxi Zheng Libing Zheng Jinxing Zhu Hua Fan Jiao Li Dongsheng Wang Sujithra KWeragoda Rohan Weerasooriya Yuansong Wei 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2021年第6期430-443,共14页
Coagulation-based pre-treatment efficiency of high strength digestate of food waste(HSDFW) anaerobic digestion is negated by organic ligand-catalyzed decomposition of coagulants. In this study, an efficient HSDFW pre-... Coagulation-based pre-treatment efficiency of high strength digestate of food waste(HSDFW) anaerobic digestion is negated by organic ligand-catalyzed decomposition of coagulants. In this study, an efficient HSDFW pre-treatment method, magnetic seeds(MS) coagulation, was employed by using highly stable Keggin Al_(30) nanocluster(PAC_(30)), MS and polyacrylamide(PAM), and its operation was optimized by evaluating the performance of removing turbidity, total suspended solids(TSS), chemical oxygen demand(COD), and total phosphorous(TP) phosphate. Results showed that at the optimum dosage of 4.82 g/L, PAC_(30) demonstrated excellent removals as high as 98.93% ± 0.1% of turbidity, 98.04% ± 0.1% of TSS, 58.28% ± 0.3% of total COD, 99.98% ± 0.01% of TP and 99.50% ± 0.01% of dissolved phosphate, respectively. Apparent molecular weight(AMW) and three-dimensional excitation-emission matrix(3 D-EEM) fluorescence spectroscopy analyses demonstrated more efficient removal of dissolved organic matter(DOM), particularly non-biodegradable and hydrophobic components by PAC_(30) than commercial coagulant. The sedimentation was much improved from 40 min by coagulation/flocculation to about 5 min settling by MS coagulation. The PAC_(30) based magnetic coagulation(MC) presents theoretical guidance on a cost-effective and much less footprint pre-treatment alternative for high strength wastewater. 展开更多
关键词 Magnetic coagulation Keggin nanocluster Pre-treatment Removal mechanism Cost analysis
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Ca^2+ and SO4^2- interactions with dissolved organic matter: Implications of groundwater quality for CKDu incidence in Sri Lanka 被引量:1
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作者 Madhubhashini Makehelwala Yuansong Wei +1 位作者 Sujithra K.Weragoda Rohan Weerasooriya 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2020年第2期326-337,共12页
It has recently been proposed that recalcitrant dissolved organic carbon(DOC) in groundwater plays a potent etiological role in the peculiar distribution of chronic kidney disease of unknown etiology(CKDu).This study ... It has recently been proposed that recalcitrant dissolved organic carbon(DOC) in groundwater plays a potent etiological role in the peculiar distribution of chronic kidney disease of unknown etiology(CKDu).This study aims to elucidate the interactions of Ca^2+and SO4^2-with a model organic fraction of humic acid(SHA) to determine the possible relationship of CKDu incidence with the DOC in drinking water.XPS and FT-IR methods respectively determined the surface functional groups and chemical composition of protonated dissolved organic carbon(HDOC) in a CKDu high-risk zone(HR) of Sri Lanka and in SHA.Higher surface C composition(87.9%) and lower O(11.4%) were observed for HDOC from the HR region than for SHA(C: 73.8%, O: 24.7%).Aromatic C with less Ocontaining functional groups was observed in HDOC.The IR band at 1170 cm^-1 confirms the formation of organic sulfonate(C–SO3^-) on SHA.A band at 1213 cm^-1 due to organic sulfonate in HDOC from the CKDu HR region was also identified.The IR band at 866 cm^-1 evidenced the formation of CaCO3 on SHA above pH 7.4.XPS data confirmed the presence of sulfur oxidation states corresponding to SO3^2-and SO4^2-at 168.9 eV and 170.1 eV binding energies,respectively.The binding energies at 347 eV and 351 eV for Ca 2p3/2 and Ca 2p1/2 eV,respectively, confirmed the bidentate complexation of Ca^2+with COO-and sulfonate groups on SHA.The organic sulfonate formed is postulated as a uremic toxicant. 展开更多
关键词 Dissolved organic carbon SULFATE Calcium ESTER group BIDENTATE
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Asymptotic Energy Expansion for Rational Power Polynomial Potentials
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作者 Asiri Nanayakkara 《Communications in Theoretical Physics》 SCIE CAS CSCD 2012年第11期645-648,共4页
Asymptotic energy expansion method is extended for polynomial potentials having rational powers. New types of recurrence relations are derived for the potentials of the form V(x)= x2n/m+b1xn1/m1+b2x n2/m2+ …+ bNxnN/m... Asymptotic energy expansion method is extended for polynomial potentials having rational powers. New types of recurrence relations are derived for the potentials of the form V(x)= x2n/m+b1xn1/m1+b2x n2/m2+ …+ bNxnN/mN where n, m, n1, m1, . . . , nN, mN are positive integers while coefficients bk∈C. As in the case of even degree polynomial potentials with integer powers, all the integrals in the expansion can be evaluated analytically in terms of Γ functions. With the help of two examples, we demonstrate the usefulness of these expansions in getting analytic insight into the quantum systems having rational power polynomial potentials. 展开更多
关键词 多项式 有理性 能量 扩展方法 递推关系 量子系统 正整数 式电位
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Climate change induced vulnerability and adaption for dengue incidence in Colombo and Kandy districts: the detailed investigation in Sri Lanka
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作者 Lahiru Udayanga Nayana Gunathilaka +1 位作者 M.C.M.Iqbal WAbeyewickreme 《Infectious Diseases of Poverty》 SCIE 2020年第4期154-155,共2页
Background Assessing the vulnerability of an infectious disease such as dengue among endemic population is an important requirement to design proactive programmes in order to improve resilience capacity of vulnerable ... Background Assessing the vulnerability of an infectious disease such as dengue among endemic population is an important requirement to design proactive programmes in order to improve resilience capacity of vulnerable communities.The current study aimed to evaluate the climate change induced socio-economic vulnerability of local communities to dengue in Colombo and Kandy districts of Sri Lanka.Methods A total of 42 variables(entomological,epidemiological,meteorological parameters,land-use practices and socio-demographic data)of all the 38 Medical Officer of Health(MOH)areas in the districts of Colombo and Kandy were considered as candidate variables for a composite index based vulnerability assessment.The Principal Component Analysis(PCA)was used in selecting and setting the weight for each indicator.Exposure,Sensitivity,Adaptive Capacity and Vulnerability of all MOH areas for dengue were calculated using the composite index approach recommended by the Intergovernmental Panel on Climate Change.Results Out of 42 candidate variables,only 23 parameters(Exposure Index:six variables;Sensitivity Index:11 variables;Adaptive Capacity Index:six variables)were selected as indicators to assess climate change vulnerability to dengue.Colombo Municipal Council(CMC)MOH area denoted the highest values for exposure(0.89:exceptionally high exposure),sensitivity(0.86:exceptionally high sensitivity)in Colombo,while Kandy Municipal Council(KMC)area reported the highest exposure(0.79:high exposure)and sensitivity(0.77:high sensitivity)in Kandy.Piliyandala MOH area denoted the highest level of adaptive capacity(0.66)in Colombo followed by Menikhinna(0.68)in Kandy.The highest vulnerability(0.45:moderate vulnerability)to dengue was indicated from CMC and the lowest indicated from Galaha MOH(0.15;very low vulnerability)in Kandy.Interestingly the KMC MOH area had a notable vulnerability of 0.41(moderate vulnerability),which was the highest within Kandy.Conclusions In general,vulnerability for dengue was relatively higher within the MOH areas of Colombo,than in Kandy,suggesting a higher degree of potential susceptibility to dengue within and among local communities of Colombo.Vector Controlling Entities are recommended to consider the spatial variations in vulnerability of local communities to dengue for decision making,especially in allocation of limited financial,human and mechanical resources for dengue epidemic management. 展开更多
关键词 DENGUE Climate change VULNERABILITY Sri Lanka
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Efficient dye-sensitized solar cells from mesoporous zinc oxide nanostructures sensitized by N719 dye
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作者 G.R.A.Kumara U.Deshapriya +2 位作者 C.S.K.Ranasinghe E.N.Jayaweera R.M.G.Rajapakse 《Journal of Semiconductors》 EI CAS CSCD 2018年第3期25-30,共6页
Dye-sensitized solar cells(DSCs) have attracted a great deal of attention due to their low-cost and high power conversion efficiencies. They usually utilize an interconnected nanoparticle layer of TiO2 as the electr... Dye-sensitized solar cells(DSCs) have attracted a great deal of attention due to their low-cost and high power conversion efficiencies. They usually utilize an interconnected nanoparticle layer of TiO2 as the electron transport medium. From the fundamental point of view, faster mobility of electrons in Zn O is expected to contribute to better performance in DSCs than TiO2, though the actual practical situation is quite the opposite. In this research, we addressed this problem by first applying a dense layer of Zn O on FTO followed by a mesoporous layer of interconnected Zn O nanoparticle layer, both were prepared by spray pyrolysis technique. The best cell shows a power conversion efficiency of 5.2% when the mesoporous layer thickness is 14 μm and the concentration of the N719 dye in dye coating solution is 0.3 m M, while a cell without a dense layer shows 4.2% under identical conditions. The surface concentration of dye adsorbed in the cell with a dense layer and that without a dense layer are5.00 × 10^(-7) and 3.34 × 10^(-7) mol/cm^2, respectively. The cell with the dense layer has an electron lifetime of-54.81 ms whereas that without the dense layer is 11.08 ms. As such, the presence of the dense layer improves DSC characteristics of Zn O-based DSCs. 展开更多
关键词 dye-sensitized solar cell mesoporous ZnO layer ZnO dense layer DSC characteristics
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Notes for genera:basal clades of Fungi(including Aphelidiomycota,Basidiobolomycota,Blastocladiomycota,Calcarisporiellomycota,Caulochytriomycota,Chytridiomycota,Entomophthoromycota,Glomeromycota,Kickxellomycota,Monoblepharomycota,Mortierellomycota,Mucoromycota,Neocallimastigomycota,Olpidiomycota,Rozellomycota and Zoopagomycota) 被引量:2
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作者 Nalin N.Wijayawardene Julia Pawłowska +23 位作者 Peter M.Letcher Paul M.Kirk Richard A.Humber Arthur Schüßler Marta Wrzosek Anna Muszewska Alicja Okrasińska Łukasz Istel Aleksandra Gęsiorska Paul Mungai Adebola Azeez Lateef Kunhiraman C.Rajeshkumar Rajshree V.Singh Renate Radek Grit Walther Lysett Wagner Christopher Walker D.Siril A.Wijesundara Moslem Papizadeh Somayeh Dolatabadi Belle D.Shenoy Yuri S.Tokarev Saisamorn Lumyong Kevin D.Hyde 《Fungal Diversity》 SCIE 2018年第5期43-129,共87页
Compared to the higher fungi(Dikarya),taxonomic and evolutionary studies on the basal clades of fungi are fewer in number.Thus,the generic boundaries and higher ranks in the basal clades of fungi are poorly known.Rece... Compared to the higher fungi(Dikarya),taxonomic and evolutionary studies on the basal clades of fungi are fewer in number.Thus,the generic boundaries and higher ranks in the basal clades of fungi are poorly known.Recent DNA based taxonomic studies have provided reliable and accurate information.It is therefore necessary to compile all available information since basal clades genera lack updated checklists or outlines.Recently,Tedersoo et al.(MycoKeys 13:1–20,2016)accepted Aphelidiomycota and Rozellomycota in Fungal clade.Thus,we regard both these phyla as members in Kingdom Fungi.We accept 16 phyla in basal clades viz.Aphelidiomycota,Basidiobolomycota,Blastocladiomycota,Calcarisporiellomycota,Caulochytriomycota,Chytridiomycota,Entomophthoromycota,Glomeromycota,Kickxellomy-cota,Monoblepharomycota,Mortierellomycota,Mucoromycota,Neocallimastigomycota,Olpidiomycota,Rozellomycota and Zoopagomycota.Thus,611 genera in 153 families,43 orders and 18 classes are provided with details of classification,synonyms,life modes,distribution,recent literature and genomic data.Moreover,Catenariaceae Couch is proposed to be conserved,Cladochytriales Mozl.-Standr.is emended and the family Nephridiophagaceae is introduced. 展开更多
关键词 Invalid genera Nephridiophagaceae fam.nov. Outline Phylogeny Validation
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Notes for genera:Ascomycota 被引量:1
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作者 Nalin N.Wijayawardene Kevin D.Hyde +94 位作者 Kunhiraman C.Rajeshkumar David L.Hawksworth Hugo Madrid Paul M.Kirk Uwe Braun Rajshree V.Singh Pedro W.Crous Martin Kukwa Robert Lücking Cletus P.Kurtzman Andrey Yurkov Danny Haelewaters Andre´Aptroot H.Thorsten Lumbsch Einar Timdal Damien Ertz Javier Etayo Alan J.L.Phillips Johannes Z.Groenewald Moslem Papizadeh Laura Selbmann Monika C.Dayarathne Gothamie Weerakoon E.B.Gareth Jones Satinee Suetrong Qing Tian Rafael F.Castanda-Ruiz Ali H.Bahkali Ka-Lai Pang Kazuaki Tanaka Dong Qin Dai Jariya Sakayaroj Martina Hujslová Lorenzo Lombard Belle D.Shenoy Ave Suija Sajeewa S.N.Maharachchikumbura Kasun M.Thambugala Dhanushka N.Wanasinghe Bharati O.Sharma Subhash Gaikwad Gargee Pandit Laura Zucconi Silvano Onofri Eleonora Egidi Huzefa A.Raja Rampai Kodsueb Marcela E.S.Caceres Sergio Perez-Ortega Patrícia O.Fiuza Josiane Santana Monteiro Larissa N.Vasilyeva Roger G.Shivas Maria Prieto Mats Wedin Ibai Olariaga Adebola Azeez Lateef Yamini Agrawal Seyed Abolhassan Shahzadeh Fazeli Mohammad Ali Amoozegar Guo Zhu Zhao Walter P.Pfliegler Gunjan Sharma Magdalena Oset Mohamed A.Abdel-Wahab Susumu Takamatsu Konstanze Bensch Nimali Indeewari de Silva AndréDe Kesel Anuruddha Karunarathna Saranyaphat Boonmee Donald H.Pfister Yong-Zhong Lu Zong-Long Luo Nattawut Boonyuen Dinushani A.Daranagama Indunil C.Senanayake Subashini C.Jayasiri Milan C.Samarakoon Xiang-Yu Zeng Mingkwan Doilom Luis Quijada Sillma Rampadarath Gabriela Heredia Asha J.Dissanayake Ruvishika S.Jayawardana Rekhani H.Perera Li Zhou Tang Chayanard Phukhamsakda Margarita Hernańdez-Restrepo Xiaoya Ma Saowaluck Tibpromma Luis F.P.Gusmao Darshani Weerahewa Samantha C.Karunarathna 《Fungal Diversity》 SCIE 2017年第5期1-594,共594页
Knowledge of the relationships and thus the classification of fungi,has developed rapidly with increasingly widespread use of molecular techniques,over the past 10–15 years,and continues to accelerate.Several genera ... Knowledge of the relationships and thus the classification of fungi,has developed rapidly with increasingly widespread use of molecular techniques,over the past 10–15 years,and continues to accelerate.Several genera have been found to be polyphyletic,and their generic concepts have subsequently been emended.New names have thus been introduced for species which are phylogenetically distinct from the type species of particular genera.The ending of the separate naming of morphs of the same species in 2011,has also caused changes in fungal generic names.In order to facilitate access to all important changes,it was desirable to compile these in a single document.The present article provides a list of generic names of Ascomycota(approximately 6500 accepted names published to the end of 2016),including those which are lichen-forming.Notes and summaries of the changes since the last edition of‘Ainsworth&Bisby’s Dictionary of the Fungi’in 2008 are provided.The notes include the number of accepted species,classification,type species(with location of the type material),culture availability,life-styles,distribution,and selected publications that have appeared since 2008.This work is intended to provide the foundation for updating the ascomycete component of the"Without prejudice list of generic names of Fungi"published in 2013,which will be developed into a list of protected generic names.This will be subjected to the XIXth International Botanical Congress in Shenzhen in July 2017 agreeing to a modification in the rules relating to protected lists,and scrutiny by procedures determined by the Nomenclature Committee for Fungi(NCF).The previously invalidly published generic names Barriopsis,Collophora(as Collophorina),Cryomyces,Dematiopleospora,Heterospora(as Heterosporicola),Lithophila,Palmomyces(as Palmaria)and Saxomyces are validated,as are two previously invalid family names,Bartaliniaceae and Wiesneriomycetaceae.Four species of Lalaria,which were invalidly published are transferred to Taphrina and validated as new combinations.Catenomycopsis Tibell&Constant.is reduced under Chaenothecopsis Vain.,while Dichomera Cooke is reduced under Botryosphaeria Ces.&De Not.(Art.59). 展开更多
关键词 Article 59 Classification One name Pleomorphic fungi TAXONOMY
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