Accelerated photocatalytic degradation of organic pollutants using graphitic carbon nitride assisted chemistry of MXenes 2D/2D nanocomposites

Vigneshwaran Sivakumar(Sivakumar Vigneshwaran),Do-Gun Kim(김도군),Seo-Oh Ko(고석오) 대한환경공학회 2022 대한환경공학회 학술발표논문집 Vol.2022 No.11

Effect of heating location and size on mixed convection in lid-driven cavities

Sivakumar, V.,Sivasankaran, S.,Prakash, P.,Lee, J. Pergamon Press ; Elsevier Science Ltd 2010 COMPUTERS & MATHEMATICS WITH APPLICATIONS - Vol.59 No.9

A numerical study is performed to analyze the mixed convection heat transfer and fluid flow in lid-driven cavities with different lengths of the heating portion and different locations of it. The left wall has been heated fully or partially to a higher temperature, whereas the right wall is maintained at a lower temperature. Three different lengths of the heating portion and three different locations of it are used along the hot wall. The remaining portions of the left wall, and the top and the bottom walls of the cavity are insulated. The finite volume method is used to discretize the governing equations which are then solved iteratively. The velocities and pressure are coupled by the SIMPLE algorithm. Results are presented graphically in the form of streamlines, isotherms and velocity profiles. It is concluded that the heat transfer rate is enhanced on reducing the heating portion and when the portion is at middle or top of the hot wall of the cavity.

Effect of continuous or intermittent radiation on sweet potato plantlets <i>in vitro</i>

Sivakumar, G.,Heo, J. W.,Kozai, T.,Paek, K. Y. Informa UK (TaylorFrancis) 2006 The journal of horticultural science & biotechnolo Vol.81 No.3

Heavy Metal Contents in Sewage and Sludge Samples and Evaluation of the Heavy Metal Phytoremediation Efficiency of Portulaca oleracea L.

Sivakumar. S,Song Young?Chae,D. Prabha,In?Seok Park,Sung Hwoan Cho 한국대기환경학회 2007 한국대기환경학회 학술대회논문집 Vol.- No.-

Evolution of Agrometeorology at the Global Level

Sivakumar, M.V.K. 한국농림기상학회 2004 한국농림기상학회지 Vol.6 No.2

농업기상은 지난 100년동안 서술적인 학문에서 물리학적 및 생물학적 법칙을 활용하는 정량적인 학문적으로 발전되어 왔다. 농업인들은 기후와 기상정보의 이용으로 수익을 개선할 수 있다는 점을 더욱 깊이 인식하게 되었고, 이는 농업기상서비스에 대한 수요를 증대로 이어질 것이라는 점은 의심할 여지가 없다. 그러므로 21세기 농업기상의 필요성과 전망을 크게 두 가지 주제로 구분하는 것은 시의 적절하다 할 수 있다. 즉 농업생산을 위한 농업기상서비스와 이들 서비스를 지원하기 위한 농업기상자원시스템의 중요한 구성요소인 자료, 연구, 정책 및 훈련/교육/지도의 중요성이 더욱 강조될 것이다. 몬티쓰박사가 말한 바와 같이, 식량공급은 궁극적으로 기상자원의 잠재성을 탐구하거나 악기상의 영향을 최소화하는 농민의 기술력에 좌우될 것이다. 장비, 자료관리체계, 기후예측, 작물모의, 농업기상정보 배분등에 있어서의 최근 발전으로 인해 농민이 이러한 핵심기술을 습득, 향상시키는 것을 돕기 위해 필요한 도구들이 농업기상학자들에게 제공되고 있다. 따라서 향후 농업기상기술의 현장활용은 그 전도가 매우 밝다 하겠으며, 이러한 기술의 현장활용을 통해 지속농업의 촉진 및 빈곤타파 등에 농업기상이 근원적인 커다란 기여를 할 수 있을 것이다. Agricultural meteorology has advanced during the last 100 years from a descriptive to a quantitative science using physical and biological principles. The agricultural community is becoming more aware that using climate and weather information will improve their profitability and this will no doubt increase the demand for agrometeorological services. Hence it is timely that the needs and perspectives for agrometeorology in the 21^(st) Century are grouped under two major headings: agrometeorological services for agricultural production and agrometeorological support systems for such services. Emphasis must be placed on the components of such support systems comprising of data, research, policies and training/ education/extension. As Monteith (2000) mentioned, food supplies ultimately depend upon the skill with which farmers can exploit the potential of good weather and minimize the impact of bad weather: Recent developments in instrumentation, data management systems, climate prediction, crop modelling, dissemination of agrometeorological information etc., provide agrometeorologicts the tools necessary help the farmers improve such skills. The future for operational applications of agricultural meteorology appears bright and such applications could contribute substantially to promote sustainable agriculture and alleviate poverty.

Behaviour of Cold Formed Steel Built-Up Channel Columns Strengthened Using CFRP

Sivakumar Naganathan,H. G. Nahushananda Chakravarthy,Noor Amalina Anuar,Sreedhar Kalavagunta,Kamal Nasharuddin Bin Mustapha 한국강구조학회 2020 International Journal of Steel Structures Vol.20 No.2

This paper presents experimental findings of carbon fibre reinforced polymer (CFRP) strengthened cold-formed steel built-up channels subjected to axial load. In order to sensitively detect the buckling strengths and failure modes, twenty-four built-up columns were tested in which twelve columns were unadorned and another twelve columns were strengthened using CFRP sheets. The columns were tested for ultimate load, lateral displacement and failure modes. Tension coupon tests were conducted to determine the material properties of test specimens. The experimental results were compared with the design load calculated according to AISI S100-16 specification and are found to be in good agreement. It is established that the use of CFRP for strengthening increases the ultimate load and delays the buckling.

Meat Quality and Physicochemical Trait Assessments of Berkshire and Commercial 3-way Crossbred Pigs

Sivakumar Allur Subramaniyan,강다래,Shah Ahmed Belal,조은소리,정종현,정영철,최양일,심관섭 한국축산식품학회 2016 한국축산식품학회지 Vol.36 No.5

In this study, we compared qualities and physiochemical traits of meat from Berkshire (black color) pigs with those of meat from 3-way Landrace (white color) × Yorkshire (white color) × Duroc (red color) crossbred pigs (LYD). Meat quality characteristics, including pH, color, drip loss, cooking loss, and free amino acid, fatty acid, vitamin, and mineral contents of longissimus dorsi muscles, were compared. Meat from Berkshire pigs had deeper meat color (redness), higher pH, and lower drip loss and cooking loss than meat from LYD pigs. Moreover, meat from Berkshire pigs had higher levels of phosphoserine, aspartic acid, threonine, serine, asparagine, α-aminoadipic acid, valine, methionine, isoleucine, leucine, tyrosine, histidine, tryptophan, and carnosine and lower levels of glutamic acid, glycine, alanine, and ammonia than did meat from LYD pigs. The fatty acids oleic acid, docosahexaenoic acid (DHA), and monounsaturated fatty acids (MUFA) were present in significantly higher concentrations in Berkshire muscles than they were in LYD muscles. Additionally, Berkshire muscles were significantly enriched with nucleotide components (inosine), minerals (Mg and K), and antioxidant vitamins such as ascorbic acid (C) in comparison with LYD muscles. In conclusion, our results show that in comparison with LYD meat, Berkshire meat has better meat quality traits and is a superior nutritional source of all essential amino acids, monounsaturated fatty acids, vitamin C, and minerals (Mg and K).

Antitumor and antioxidant activities of Bryonia laciniosa against Ehrlich's Ascites Carcinoma bearing Swiss albino mice

Sivakumar, T,Kumar, R Sambath,Perumal, P,Vamsi, MLM,Sivakumar, P,Kanagasabai, R,Baskaran, MV,Karki, Subhas S,Mazumder, UK,Gupta, M Kyung Hee Oriental Medicine Research Center 2005 Oriental pharmacy and experimental medicine Vol.5 No.4

The plant Bryonia laciniosa (Family: Cucurbitaceae) has been indicated for the treatment of various diseases one among which is cancer. The purpose of this study was investigating experimentally the possible anti-tumor effect and antioxidant role of Bryonia laciniosa leaves in animal model. The methanol extract of Bryonia laciniosa (MEBL) administered at the doses of 62.5, 125 and 250 mg/kg in mice for 14 days after 24 h of tumor inoculation. The effect of MEBL on the growth of transplantable murine tumor, life span of EAC bearing mice, hematological profile and liver biochemical parameters (lipid peroxidation, antioxidant enzymes) were estimated. Treatment with MEBL decreased the tumor volume and viable cell count thereby increasing the life span of EAC bearing mice and brought back the hematological parameter more or less normal level. The effect of MEBL also decreases the levels of lipid peroxidation and increased the levels of glutathione (GSH), superoxide dismutase (SOD) and catalase (CAT). The present work indicates that the methanol extract of Bryonia laciniosa exhibited significant antitumor and antioxidant activity in vivo.

Effects of Sunphenon and Polyphenon 60 on proteolytic pathways, inflammatory cytokines and myogenic markers in H2O2-treated C2C12 cells.

Sivakumar, Allur Subramaniyan,Hwang, Inho Indian Academy of Sciences 2015 Journal of biosciences Vol.40 No.1

<P>The effect of Sunphenon and Polyphenon 60 in oxidative stress response, myogenic regulatory factors, inflammatory cytokines, apoptotic and proteolytic pathways on H2O2-induced myotube atrophy was addressed. Cellular responses of H2O2-induced C2C12cells were examined, including mRNA expression of myogenic regulatory factors, such as MyoD and myogenin, inflammatory pathways, such as TNF-alpha and NF-kB, as well as proteolytic enzymes, such as mu-calpain and m-calpain. The pre-treatment of Sunphenon (50 mu g/mL)/Polyphenon 60 (50 mu g/naL) on H2O2-treated C2C12 cells significantly down-regulated the mRNA expression of myogenin and MyoD when compared to those treated with H2O2-induced alone. Additionally, the mRNA expression of mu-calpain and m-calpain were significantly (p<0.05) increased in H2O2-treated C2C12 cells, whereas pre-treatment with Sunphenon/Polyphenon significantly down-regulated the above genes, namely mu-calpain and m-calpain. Furthermore, the mRNA expression of TNF-alpha and NF-kB were significantly increased in H2O2-treated C2C12 cells, while pre-treatment with Sunphenon (50 mu g/mL)/Polyphenon 60 (50 mu g/mL) significantly (p<0.05) down-regulated it when compared to the untreated control group. Subsequent analysis of DNA degeneration and caspase activation revealed that Sunphenon (50 mu g/mL)/Polyphenon 60 (50 mu g/mL) inhibited activation of caspase-3 and showed an inhibitory effect on DNA degradation. From this result, we know that, in stress conditions, mu-calpain may be involved in the muscle atrophy through the suppression of myogenin and MyoD. Moreover, Sunphenon may regulate the skeletal muscle genes/promote skeletal muscle recovery by the up-regulation of myogenin and MyoD and suppression of mu-calpain and inflammatory pathways and may regulate the apoptosis pathways. Our findings suggest that dietary supplementation of Sunphenon might reduce inflammatory events in muscle-associated diseases, such as myotube atrophy.</P>

Growth and Characterization of Lithium Potassium Phthalate (LiKP) Single Crystals for Third Order Nonlinear Optical Applications

Sivakumar, B.,Raj, S. Gokul,Kumar, G. Ramesh,Mohan, R. Korean Chemical Society 2012 Bulletin of the Korean Chemical Society Vol.33 No.11

Single crystals of lithium potassium phthalate (LiKP) were successfully grown from aqueous solution by solvent evaporation technique. The grown crystals were characterized by single crystal X-ray diffraction. The lithium potassium phthalate $C_{16}\;H_{12}\;K\;Li_3\;O_{11}$ belongs to triclinic system with the following unit-cell dimensions at 298(2) K;$a=7.405(5){\AA}$;$b=9.878(5){\AA}$;$c=13.396(5){\AA}$;${\alpha}=71.778(5)^{\circ}$;${\beta}=87.300(5)^{\circ}$;${\gamma}=85.405(5)^{\circ}$; having a space group P1. Mass spectrometric analysis provides the molecular weight of the compound and possible ways of fragmentations occurs in the compound. Thermal stability of the crystal was also studied by both simultaneous TGA/DTA analyses. The UV-Vis-NIR spectrum shows a good transparency in the whole of Visible and as well as in the near IR range. Third order nonlinear optical studies have also been studied by Z-scan technique. Nonlinear absorption and nonlinear refractive index were found out and the third order bulk susceptibility of compound was also estimated. The results have been discussed in detail.