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Geochemistry of gem bearing stream sediments of Kalu River basin, Sri Lanka: potential for rare earth elements (REEs)
Get PDFOver the last two decades, the prospecting of Rare Earth Elements (REEs) has been
extensively increased owing to their wider industrial applications. Stream sediments
which are rich in precious gem minerals are considered as one of the emerging
alternative sources of REEs with minable concentrations. Hence the present study
aimed to investigate the REE potential of gem bearing sediments of the upper reaches
of the Kalu Ganga river basin of Sri Lanka. The mineralogy and elemental composition
of eighty-one sediment samples were analyzed on X-Ray Diffractometer (XRD) and X
Ray Fluorescence (XRF) techniques respectively. The resulted XRD spectrums
revealed the presence of major quartz and ilmenite with minor gems and REE-bearing
minerals such as andalusite, chrysoberyl, enstatite, garnet, lucasite, magnetite,
monazite, pyrite, spinel, thorneite, titanite, xenotime and zircon. The mineralogy
suggests the association of gem minerals in the studied samples. The stream sediments
indicate significant amounts of Light REEs such as Ce [average 540 (286 - 4310) ppm],
La [average 178 (457 – 1670) ppm], Nd [average 120 (1140 – 1260) ppm], Y [25 (10
111) ppm] and Gd (average 0.05 (0 – 0.98) ppm] which are even above the present day
mining sites of the world. The chemical correlations demonstrated a positive correlation
between REEs with concentrations of Ti and Zr. This suggests that the REE content is
enriched within the recognized minerals such as xenotime (YPO4), monazite
[(Ce,La,Nd,Th)PO4] and lucasite (CeTi2(O,OH)6) which might be associated with Ti
and Zr rich minerals such as zircon (ZrSiO4), ilmenite (FeTiO3) and rutile (TiO2). The
REE concentration shows increased values along the river flow direction specially, after
Ratnapura town. Thus, the study concluded that the Kalu Ganga river basin is a
prospective place for REEs. Since the REEs are associated with gem minerals, it can be
suggested that the gem mining sediments may be the best source for the REEs
CSR and sustainable development goals in Indian corporate sector
Get PDFThis research paper has made an attempt the goal of
building a better future; Corporate Social Responsibility (CSR) is a strategy
that attempts to systematically incorporate the economic, environmental, and
social impacts of business into the management of business. In addition to
creating a wealth gap between the rich and the poor, the rise of major
corporations and their desire to maximize individual profits have also thrown
development and environmental sustainability out of balance. CSR is a
concept that is frequently contested between the morality and profitability
dichotomies and is interpreted contextually. India argues that both of these
dichotomies should be combined through a mandatory CSR obligation. The
localization of both CSR and SDG has been used to address the myriad social
development difficulties posed by India's cultural diversity. In order to achieve
the sustainable development goals of Agenda 2030, the goals of the Indian
CSR programmes are further mapped to that document. This strategy has an
impact on how much money is directed towards different development
programmes through business efforts, government programmes, and
corporate initiatives. Even though there has been a lot of work done in the
theoretical realm to educate Indian corporations about the importance of social
responsibility and environmental ethics as a part of their economic activity,
very little has been accomplished so far. The study will also clarify the
theoretical and practical contributions made by CSR to the Indian corporate
sector's pursuit of sustainable development. To achieve greater harmony
between economic developments, environmental sustainability, and public
safety, efforts will be made to design a strategy that ensures greater business
sector responsibilities and engagement
Exploring the viability of kittul flour as an advanced gelling agent in plant tissue culture media
Get PDFPlant tissue culture relies on a synthetic growth medium with macronutrients,
micronutrients, organic supplements, growth regulators, and solidifying agents. Agar,
the typical solidifying agent, constitutes 70% of the media cost. This study aims to
develop a cost-effective alternative medium. In this research, a cost-effective alternative
culture medium for plant tissue culture was developed, aiming to reduce the high cost
associated with traditional agar-based media. The study focused on utilizing kithul flour
as both a gelling agent and a nutrient source. Kithul flour was analyzed for various
characteristics, including moisture content, pH value, ash content, amylose content,
swelling power, and solubility. The novel growth medium was prepared by enriching
MS media powder with essential macro and micronutrients, sucrose, and myo-inositol.
The medium's solidification was achieved by varying the ratio of agar and kithul flour.
The effectiveness of this kithul flour-based medium in supporting shoot proliferation of
mustard seeds was investigated. A two-factorial experiment was conducted, with the
first factor being the type of gelling agent. The six treatments included, Agar: Kithul
flour ratio (T0= 5:0, T1= 1:4, T2=2:3, T3=3:2 T4=4:1 T5=0:5). The second factor was
the plant species Brassica spp. The results indicated that the T3 treatment (3 parts kithul
flour to 2 parts agar) demonstrated the most promise as an alternative to the costly
100% agar-based culture media. This kithul flour-agar blend effectively supported
micro propagation and minimal growth conservation of Brassica spp. The kithul flour
starch consistently provided a stable gel surface throughout the culture period, resulting
in optimal plantlet growth in terms of shoot number, shoot length, and leaf count.
Various treatments were applied, and significant differences in critical growth
indicators were observed. Notably, Treatment T3 showed comparable results to T1 and
T2 while outperforming other treatments. In conclusion, kithul flour, when incorporated
as a gelling agent in tissue culture media, demonstrates its potential as a cost-effective
and effective alternative, with promising results for plant propagation and growth
conservation
Variations in the Pharmacognostic properties of Aegle Marmelos found across five geographical locations in Sri Lanka
Get PDFAegle marmelos (Bale tree), family-Rutaceae is a very important medicinal plant used for the Ayurveda and traditional medical systems. This study is focused on pharmacognostic characteristics of the leaves, stem barks and the root barks of Aegle marmelos (A. maemelos) found in five geographical locations in Sri Lanka. A solvent system containing, Toluene, Ethyl acetate, Formic acid and Methanol was used as mobile phase for the leaves. For stem bark and root bark extracts, Toluene: Ethyl acetate: Chloroform: Hexane: Methanol solvent system was used as the mobile phase. TLC outcomes were developed by High Performance Thin Layer Chromatography (HPTLC) technique. According to this study moisture values of the selected plant parts were in the range of 7% to 12% and ash values were in the range of 5% to 10%. pH values of the selected plant parts were varied form 5-8. Microscopic view of the root bark and stem bark were observed and tracheid and xylem vessels were detected. One common compound was detected in leaves, stem bark and root bark, and two common compounds were detected in stem bark and root bark from TLC and HPTLC profiles. It was detected that the concentrations of the similar compounds vary with plant part as well with the origin of the plant. These findings can be used for the identification and authentication of A. marmelos plant parts that are used for medicinal purposes and herbal product manufacture. A comparative clinical study is needed to explore the therapeutic efficacy of these parts
Enhancing the photocurrent of dye-sensitized solar cells by nanofiller effect
Get PDFThe overall performance of the DSSC can be enhanced by modifying the photoanode,
electrolyte, and counter electrode separately. Liquid-based redox couple electrolyte
gives high efficiency but the rapid evaporation of solvent is a major problem. To
overcome this limitation polymer electrolytes are used in dye-sensitized solar cells and
DSSCs were fabricated with Poly (vinylidene fluoride-co-hexafluoropropylene)
(PVDF-HFP) gel polymer electrolyte in this study. In order to enhance the performance
of the electrolyte, different weight percentages (wt%) of TiO2 nanoparticles were added
to the electrolyte. 2.5 wt% of the TiO2 incorporated DSSC shows a high efficiency of
5.93% while the controlled cell shows 5.69%. This improvement is due to the nanofiller
effect of the TiO2 nanoparticles in the polymer electrolytes. The overall efficiency of
the solar cell has been enhanced by 4.18% due to the effective charge transportation and
quick regeneration of dye molecules with less recombination
ESG sentiment and its impact on stock market return
Get PDFThis article investigates the connection between financial
market performance and investors' attitudes toward environmental,
social, and governance (ESG) issues. Using the top-down approach of
Baker and Wurgler (2007), the study constructs an ESG index for chosen
countries. The research used principal component analysis to build a
composite ESG index using appropriate proxies. The ESG and return
series' integration level is stationary using the ADF unit root test, which
eliminates other selected nations except for India because India's stock
return and ESG series were only integrated in the order I(0) and I(1). Error
correction reveals that only the return lag that justifies significance occurs
at a level of 10% for the short-run coefficient and at a level of 1% for the
long-run adjustment, indicating that 179% each year corrects the
disequilibrium induced by the temporal shocks of the previous period.
This finding suggests that the ESG index is in long-run equilibrium with
market performance
Fear’s influence on predator-prey interactions
Get PDFInteractions between animals and their surroundings are essential to the
survival and success of individual organisms as well as entire ecosystems. The
dynamic relationship between predators and their prey in an ecosystem is referred to
as” exploitative interactions.” The relationship between predators and prey is important
in shaping the dynamics of an ecosystem and can have a significant impact on predator
and prey populations. Predator-prey interactions can take many different forms and
are influenced by a variety of factors, including the size and behavior of the predator
and prey, the availability of resources, and the presence of other predators and prey
species. The fear effect in predator-prey interaction refers to the idea that prey animals
may exhibit altered behavior due to the perceived risk of predation. This can include
changes in movement patterns, foraging behavior, and reproductive strategies. The
fear effect is incorporated into mathematical models recently as it affects the rates of
prey reproduction. In this work, we consider the classic two-species predator-prey
model, where one of the species is “fearful” of the other when exactly the predation
happens
இபன்கட்டுவ பெருங்கற்கால மையமும் அதன் காட்சிக் கூடமும்
No full textஇலங்கையின் பண்பாட்டு வரலாற்றில் பெருங்கற்காலப்
பண்பாட்டின் பரவல் புதிய கால கட்டத்தின் தொடக்கமாக அல்லது திருப்பு
முனையாக அமைந்ததெனக் கூறலாம். பெரிய கற்களை தமது சவஅடக்க
முறைகளுக்கு பயன்படுத்தியமை காரணமாக பெருங்கற்காலம் என
அழைக்கப்படுகின்றது. இலங்கையில் பெருங்கற்காலப் பண்பாடு தொடர்பான
சான்றுகள் 1889 களில் இருந்து தெரிய வந்திருந்தாலும் நாகரீக உருவாக்கத்தில்
அப் பண்பாடு பெறும் முக்கியத்துவம் பற்றிய ஆய்வுகள் பெரும்பாலும் 1970களின்
பின்னரே உருவாக்கப்பட்டது. இலங்கையில் கடந்த இரு சகாப்த காலங்களில்
50க்கும் மேற்பட்ட இடங்களில் இப் பண்பாடு பற்றிய சான்றுகள்
கண்டறியப்பட்டுள்ளன. அவற்றுள் ஒரு முக்கிய மையமாக இபன்கட்டுவ
பெருங்கற்கால மையம் அமைவு பெறுகின்றது. இம் மையம் மத்திய மாகாணத்தின்
மாத்தளை மாவட்டத்தின் கலகவல பிரதேசத்தில் அமைந்துள்ளது. இம் மையத்தின்
சிறப்பியல்பே 2500 வருட காலத்திற்கு முன்னைய இடுகாட்டுப் பரப்பு
கண்டறியப்பட்டமையாகும். இங்கு இரண்டு சவ அடக்க முறைகளான கல்லறைகள்,
ஈமத்தாழிகள் என்பன முக்கியத்துவம் பெற்று விளங்குகின்றன. அத்துடன் பண்டைய
கால சமூகத்தில் மக்கள ; இறந்ததற்குப் பின்பு அவர்களுக்கு மறுவாழ்வு உண்டு என்ற நம்பிக்கையில் அவர்கள் வாழ் நாளில் பயன்படுத்திய
பொருட்களை அவர்களின் இறந்த உடலுடன் சேர்த்து புதைத்தனர். இதனால்
பல்வேறு வகையிலான சவ அடக்க முறைகளை பின்பற்றியிருந்தனர். அவற்றுள்
கல்லறைகள், கற்திட்டைகள், தாழிகள் என்பன முக்கியம் பெறுகின்றன.அவ்வகையில்
இவ் இபன்கட்டுவ மைய அகழ்வாய்வில் இறந்தவர்களுக்கான சவ அடக்க
முறைகளுடன் பல்வேறு வகையான தொல்லியல் சான்றுகள்
கண்டுபிடிக்கப்பட்டுள்ளன. அவற்றுள் மட்பாண்டங்கள், சிறிய அளவிலான சட்டிகள்,
கலசங்கள், பானைகள், குவளைகள், வட்டில்கள், கறுப்பு சிவப்பு நிற
மட்பாண்டங்கள், பல்வேறு வகையிலான ஆபரணப் பொருட்கள், சடங்குகளுக்கு
பயன்படுத்தப்பட்ட பொருட்கள், கல்மணிகள், அயல் நாட்டு மட்பாண்டங்கள்,
நாணயங்கள், குறியீடுகள் பொறிக்கப்பட்ட மட்பாண்ட துண்டுகள்,
சுடுமண்ணுருவங்கள், இரும்பு பொருட்கள் என்பன சிறப்பாக குறிப்பிடத்தக்கன.
இத்தகைய ஆதாரங்களை அடிப்படையாகக் கொண்டு இபன்கட்டுவ பெருங்கற்கால
மையத்தில் நிலவிய புராதன மக்களது மொழி, எழுத்து, அரசியல், பொருளாதாரம்,
சமூகம், சமயம், மக்களது வாழ்வியல் அம்சங்ள், சடங்குகள், சம்பிரதாயங்கள்,
நாளாந்தம் பயன்படுத்தப்பட்ட பாவனைப் பொருட்கள், சவ அடக்க முறைகள், அயல்
நாடுகளுடன் கொண்ட தொடர்புகள், உலோகப் பாவனை, கலைமரபு போன்ற
விடயங்களை ஆராய்வதே இவ் ஆய்வின் நோக்கம் ஆகும். இவ் ஆய்வின் துணை
நோக்கமாக இபன்கட்டுவ தொல்லியல் மையத்தின் காட்சிக் கூடம் தொடர்பாக
ஆராய்வதாகும். வரலாற்று அணுகுமுறையின் அடிப்படையில் விவரண ஆய்வாக
அமையப்பெற்ற இவ்வாய்விற்கு தேவையான தகவல்கள் முதல்நிலை தரவுகள்,
இரண்டாம் நிலைத் தரவுகள் என்ற அடிப்படையில் பெறப்பட்டன. அவ்வகையில்
நேர்காணல்கள், களஆய்வுகள் முதல்நிலைத் தரவுகள் என்ற வகையில் அடங்க
குறித்த இவ்விடயம் தொடர்பாக வெளிவந்த நூல்கள், ஆய்வுக் கட்டுரைகள்,
சஞ்சிகைகள் இரண்டாம் நிலைத் தரவுகளாகவுள்ளன
Jaffna under the rule of Dutch- a study based on the Dutch report-1658.
Get PDFThe history of Sri Lankan Administration was changed with
several new aspects in the European period. “Administration is a process of
systematically arranging and coordinating”. Thus, the administration of a
government should be organized and coordinated. It is noted that such
administrative system was changed as per the purpose of rule of
Portuguese, Dutch and British in accordance with the period of Europeans.
Among such Europeans Dutch, ruled from the period 1658 to 1796. Under
their administration it was ruled the coastal areas of Ceylon by the three
Commanderies namely Colombo, Galle and Jaffna. Among such three
Commanderies Jaffna Commandery plays the significant part. The
documents belonged to Dutch period help to identify the salient features of
Jaffna commandery. The identity of Jaffna Commandery was shown through
several reports of Dutch. It can be easily known the political economical
religious and social aspects of Jaffna by such reports. So the purpose of this
study is to know the importance of Jaffna Commandery from the Dutch
Report, published by Rijckloff vanGoens in 1658. This research is carried
out based on the primary and secondary data using the historical and
descriptive analysis. The research will be useful to reveal the importance of
Dutch documents and to expose several aspects which were not exposed
before. And it will be supportive to the Jaffna society