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Larvicidal activity of Dregea volubilis and Bombax malabaricum leaf extracts against the filarial vector Culex quinquefasciatus

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Asian pacific Journal of Tropical Medicine 2011年第6期4卷 436-441页

作者： Emdad Hossain Anjali Rawani Goutam chandra Subhash C.Mandal Jayanta Kumar Gupta pharmacy College AzamgarhItauraPO:ChandeshwarAzamgarh 276128Uttar PradeshIndia Department of Zoology Mosquito Research UnitParasitology LaboratoryThe University of BurdwanBurdwan 713104West BengalIndia Department of pharmaceutical Technology Jadavpur UniversityKolkata 700032India

Objective:To analyze the larvicidal activity of two plant leaf powder and leaf-extracts, Dregea volubilis and Bombax malabaricum against Culex ***:The larvicidal bioassay was done for powdered leaves of Dregea volubilis and Bombax malabaricum individually and their methanol extracts against first-,second-,third- and fourth-instar larval forms of Culex *** rate was recorded after 24,48 and 72 h of postexposure. LC50 and LG90 values were calculated at different time intervals for third instar larvae. Results:All the graded concentration（0.1%,0.2%,0.3%,0.4%,0.5%） of powdered leaves showed significant（p ppm doses of methanolic extracts of both the plants against Culex *** corresponding 50 values were 56.97 ppm and 48.85 ppm,respectively after 24 h of *** is no mortality of non-target organism such as Chironomous circumdatus,Oreochromis niloticus niloticus and Diplonichus annulatum within 72 h of post exposure to 0.1%,0.2%,0.3%crude powdered leaves and methanolic extracts of both the two individual plants under the laboratory *** results of preliminary qualitative phytochemical analysis of both the plants revealed the presence of many bioactive principles such as steroids,tannins,flavonoids,triterpenoids,saponins,etc. that may be responsible for their bio-control ***:The results have shown potential and eco-friendly use of both plant extracts against larva of Culex quinquefasciatus for the first time.

关键词： Bombax malabaricum Culex quinquefasciatus Dregea volubilis Larvicidal activity

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Development of Iron Based Brake Friction MMC Used for Military Aircraft Application by A New p/M Route

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Journal of Minerals and Materials Characterization and Engineering 2011年第8期10卷 693-705页

作者： Mohammad Asif K. chandra p.S. Misra Metallurgical and Materials Engineering Department Indian Institute of Technology Roorkee.Roorkee- 247667 India

A new p/M route based hot powder pre-form forging process has been evolved to develop high density brake materials for heavy duty applications. Number of iron based MMC’s so developed offer better characteristics for braking applications in comparison to the materials developed through conventional p/M route based on high pressure compaction and pressure sintering. The process so developed in the present investigations is much simpler and easy to adopt by existing p/M industries. Hot powder pre-form forging technique for making heavy duty brake pads offers better opportunity for pore free material with better bonding between various metallic and non-metallic constituents. After conducting an initial characterization such as hardness, density and pin-on Disc tests, the samples were tested for high energy (32,933kgfm) on Sub-scale dynamometer under Rejected Take Off conditions. The results have also been compared with respect to brake pads employed in heavy duty Military aircraft tested under identical laboratory conditions. The present work indicates that the newly developed materials compare better than the one being currently employed in heavy duty aircraft. The reasons for better performance are improved processing technique and resulting higher levels of density and improved binding of the product.

关键词： brake pad heavy duty Aircraft brakes powder Metallurgy.

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Cardioprotective effect of Urena lobataleaves extract on diabetic rats

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中国药理学与毒理学杂志 2015年第S1期29卷 118-119页

作者： chandra Analis Ahmat Baihaki Elok Zakiyyatu Sholehah Yudi purnomo School of Medicine Malang Islamic University Indonesia

OBJECTIVE To know cardioprotective effect of *** extract on diabetic *** This study uses control group post test only with male sprague dawley *** rats was induced by high fructose diet(HFD)and single dose streptozotocin 25mg·kg-1 bw intra *** rat was administrated orally with water extract of *** in concentrations of 250,500 and 1000mg·kg-1 bw for 4 *** scarifying,heart organ were collected and then superoxyde dismutase(SOD)heart level,malondialdehyda(MDA)and tumor necrosis factor-alpha(TNF-α)were *** data was analyzed using ANOVA test continued with LSD test(ppectively compared to diabetic group(pppplementation of water extract from *** dose of 250,500 and 1000mg·kg-1 bw were also decrease TNF-αheart level approximately 20%,40% and 60% compared to control group(pps,SOD heart level was decreased compared to normal group(ppprotector on diabetic rats by increasing of SOD heart level,decreasing of MDA heart level and TNF-α.This effect may be related to active compounds that act as an antioxidant and anti-inflammatory in *** extract.

关键词： U.lobata diabetic cardioprotective SOD MDA TNF-α

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An Acoustic Analysis of Fluctuations for Inter-and Intra-Speaker Variability in Speech Sounds

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Journal of Forensic Science and Medicine 2023年第1期9卷 38-43页

作者： Jasdeep Kaur Kailash chandra Juglan Kush Sharma Vishal Sharma Department of physics School of Chemical Engineering and Physical Sciences Lovely Professional UniversityPhagwaraPunjab Data Manager School of Community Medicine and Public HealthPostgraduate Institute of Medical Education and ResearchChandigarh Institute of Forensic Science and Criminology Panjab UniversityChandigarhIndia

Background:Variation in the speech of speakers is a crucial issue for the forensic *** main reason behind incorrect speaker identification is greater intra-speaker *** the forensic state of play,a lot of research has been carried out on speaker *** inter variations and intra fluctuations in speakers for the punjabi language is still a grey *** and Objectives:Our aim is to study acoustic analysis of fluctuations for inter and intra speaker variability in speech *** our study,we will consider punjabi vowel with *** Statistical methods will be applied to analyze the data;firstly,the Shapiro-Wilk test will be checked for normality and then Levene’s Test to assess the equality of *** and Method:Five vowels were selected with different *** were combined to make meaningful *** these meaningful words were embedded in *** speakers participated *** are students of A.S College at Khanna in *** individuals were aged between 20-22 years with no hearing or speech *** voice samples were recorded with help of good quality microphone and by Goldwave software in the sound proof *** were introduced directly into pRAAT software by the use of a Sony microphone and with sampling rate of 44100 Hz *** Analysis has been done with help of Goldwave software in form of *** and Conclusion:Each formant shows a different value for inter variations and inter speaker fluctuations.F1 and F2 shows lesser speaker variation than the high-frequency region in F3 and F4,so we can say that in comparison with the lower part,high-frequency regions are more *** assumptions for TWO-WAY ANOVA is violated and hence,we have used the non-parametric Friedman Test and performed its post hoc *** posthoc analysis,we can say that F1 and F2(p>0.05)and F2 and F3(p>0.05)gave the same type of ***,from the results of these st

关键词： Forensic voice identification Friedman test intervariations and intrafluctuations punjabi

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Mechanical properties of powder Based Steel used as Backing plate in Heavy Duty Brake pad Manufacturing

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Journal of Minerals and Materials Characterization and Engineering 2012年第5期11卷 509-518页

作者： M. Asif K. chandra p.S. Misra Department of Metallurgical and Materials EngineeringIndian Institute of Technology Roorkee Roorkee – 247667 (INDIA)

The aims of the present study is to develop a powder based steel used as backing plate for heavy duty brake pad applications. Three powder based back plate steel compositions namely B1 (C- 0.3, Cu – 1.5, p -0.3, Fe – 97.9), B2 (C- 0.1, Cu – 2.5, SiC-1, Fe – 96.4) and B3(C- 0.5, Cu – 2.5, SiC-1, Fe – 96.0) were prepared using a hot powder preform forging technique. The forged samples are of (25× 50×10 mm3) dimensions. These samples were hot rolled and annealed to relieve the residual stresses. These samples were characterized in terms of microstructure, porosity content/densification, hardness and tensile properties. Densification as high near to theoretical density has been realized. Hot powder preform forging using closed die showed better densification. Rolled and annealed microstructure showed lesser porosity content than the forged one. phosphorous causes hardening of ferrite in solid solution with iron. Compositions B1, showed reasonable elongation and it improved further on annealing. It was observed in this present investigation that, the addition, such as SiC and Cu caused increase in strength. Steel developed in the investigation are used as powder based backing plate in Manufacturing of iron based brake pads used in heavy duty applications.

关键词： powder based steel brake pad manufacturing Mechanical properties

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Development and Characterization of Fe-Based Friction Material Made by Hot powder preform Forging for Low Duty Applications

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Journal of Minerals and Materials Characterization and Engineering 2011年第13期10卷 1205-1212页

作者： A.A.S. Ghazi K. chandra p.S. Misra Department of Metallurgical and Materials Engineering Indian Institute of Technology Roorkee India.

This present paper investigates the friction and wear properties of friction material developed by ‘Hot powder preform Forging’ technique. The conventional technique to manufacture Metallo-ceramic brake pads was successfully and economically tried to replace the above process. Compacting and sintering technology suffers from certain major limitations such as inadequate joining of friction element with backing plate, poor density levels achieved in friction element owing to limited application of pressure during compacting, poor thermal conductivity due to high levels of porosity in the product, poor strength due to segregation of the impurities along prior particle boundaries (ppB’s) and, wide variations in final characteristics due to large number of variables involved. In contrast to these limitations, the present technique can offer brake pads of much simpler chemistry but with improved performance on account of simultaneous application of pressure and temperature and with better control of variables. Fade and recovery studies were carried out on a Krauss machine tester following the Economic Commission for Europe Regulation for replacement brake linings (ECE R-90). μfade, μrecovery, μperformance, % age fade , % age recovery & temperature rise lie within the range for friction materials used for low duty applications. The mechanical properties of these materials were characterized using ASTM standards.

关键词： Friction material preform forging Brake pads Fade.

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Development of Aluminium Based Hybrid Metal Matrix Composites for Heavy Duty Applications

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Journal of Minerals and Materials Characterization and Engineering 2011年第14期10卷 1337-1344页

作者： M. Asif K. chandra p.S. Misra Department of Metallurgical and Materials Engineering Indian Institute of Technology Roorkee Roorkee – 247667 (INDIA)

The present study deals with the investigation of dry sliding wear behavior of aluminium alloy based composites, reinforced with silicon carbide particles and solid lubricants such as graphite/antimony tri sulphide (Sb2S3). The first one of the composites (binary) consists of Al. with 20% Silicon Carbide particles (SiCp) only. The other composite has SiCp and solid lubricants: Graphite + Sb2S3 (hybrid composite) at solid state. Both composites are fabricated through p/M route using “Hot powder perform forging technology”. The density and hardness are measured by usual methods. The pin-on-disc dry wear tests to measure the tribological properties are conducted for one hour at different parameters namely load: 30, 50 and 80N and speed: 5, 7 and 9m/s. The tested samples are examined using scanning electron microscope (SEM) for the characterization of microstructure and tribolayer on worn surface of composites. The results reveal that wear rate of hybrid composite is lower than that of binary composite. The wear rate decreased with the increasing load and increased with increasing speed. The results of the proposed composites are compared with iron based metal matrix composites (FM01N, FM02) at corresponding values of test parameters. These iron based metal matrix composites are also fabricated by p/M route using ‘Hot powder perform forging technology’. The comparative study reveals that the proposed composites have lower friction coefficient, less temperature rise and low noise level;however they have little higher wear rate. It is concluded that the hybrid composite has acceptable level of tribological characteristics with blacky and smooth worn surface.

关键词： Al-MMC powder Metallurgy powder Forging Heavy Duty applications.

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镍铁氰化物纳米粒子的合成及其多相催化无溶剂条件下苯甲醇氧化的潜能(英文)

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催化学报 2011年第12期32卷 1844-1849页

作者： Shah R. ALI prakash chandra Mamta LATWAL Shalabh K. JAIN Vipin K. BANSAL Sudhanshu p. SINGH Department of Chemistry Kumaun University Department of Chemistry Gurukula Kangri University Department of Chemistry Indian Institute of Technology Roorkee Faculty of Chemistry Department of Applied Science Mangalayatan University

Nickel hexacyanoferrate nanoparticles were synthesized and characterized using elemental analysis, thermal analysis, infrared spectroscopy, and X-ray diffraction. A FE-SEM image of the nickel hexacyanoferrate showed that it consists of nearly spherical particles with sizes ranging from 30 to 70 nm. The synthesized material was found to be a heterogeneous catalyst useful for the solvent-free oxidation of benzyl alcohol with H2O2 as an oxidant. A 36% conversion of benzyl alcohol to benzaldehyde was achieved under optimized reaction conditions using specific parameters such as the amount of catalyst, the temperature, the benzyl alcohol to H2O2 molar ratio, and the reaction time.

关键词： hexacyanoferrate nanoparticle heterogeneous catalyst benzyl alcohol benzaldehyde

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Nasopharyngeal carcinoma in the Northeastern states of India

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Chinese Journal of Cancer 2011年第2期30卷 106-113页

作者： Amal chandra Kataki Malcolm J. Simons Ashok Kumar Das Kalpana Sharma Narinder Kumar Mehra Regional Institute for Cancer Treatment & Research Dr. B. Borooah Cancer Institute Guwahati Department of Experimental Research Sun Yat-sen University Cancer CenterGuangzhou Simons Haplomics Limited Hong Kong SAR P. R. China Department of Head & Neck Oncology Dr. B. Borooah Cancer Institute Guwahati Department of Otolaryngorhinology Gauhati Medical College Assam Department of Transplant Immunology & Immunogenetics All India Institute of Medical Sciences

Nasopharyngeal cancer (NpC) is a rare disease in most parts of the world, except for Southeast Asia, some parts of North Africa and the Arctic. It is mostly seen in people of Chinese origin. In India, NpC is also rare, except for the Hill States of Northeast India, particularly Nagaland, Manipur, and Mizoram. The striking feature of NpC in Northeast India is that the incidence ranges over the complete spectrum from the lowest (as 0.5/100 000 to 2.0/100 000 among Caucasoid) to the highest (as ~20/100 000 among Cantonese/Zhongshan dialect Chinese). The age-adjusted rate of NpC in Kohima district of Nagaland State is 19.4/100 000, which is among the highest recorded rates. By contrast, in Assam, one of the so-called Hill States but not itself a hilly state, NpC is much less common. The Northeastern region is distinguished by a preponderance of the Tibeto-Burman languages and by variable mongoloid features among peoples of the region. The nature of the migratory populations who are presumed to be bearers of the mongoloid risk is unknown, but these NpC occurrence features provide an outstanding opportunity for NpC risk investigation, such as that of the hypothesis of Wee et al. for westward displacement of Chinese aborigines following the last glacial maximum.

关键词：东北部鼻咽癌印度全国人民代表大会东北地区蒙古人种末次盛冰期特征变量

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Low-cost high entropy alloy(HEA)for high-efficiency oxygen evolution reaction(OER)

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Nano Research 2022年第6期15卷 4799-4806页

作者： Lalita Sharma Nirmal Kumar Katiyar Arko parui Rakesh Das Ritesh Kumar chandra Sekhar Tiwary Abhisek K.Singh Aditi Halder Krishanu Biswas School of Basic Sciences Advanced Materials Research Centre(AMRC)Indian Institute of Technology Mandi(H.P)KamandMandi 175005India Department of Materials Science and Engineering Indian Institute of Technology KanpurKanpur 208016India School of Engineering London South Bank UniversityLondonSE10 AAUK Materials Research Centre Indian Institute of ScienceBangalore 560012India Metallurgical and Materials Engineering Indian Institute of Technology KharagpurKharagpur 382355India

Oxygen evolution reaction(OER)is the key step involved both in water splitting devices and rechargeable metal-air batteries,and hence,there is an urgent need for a stable and low-cost material for efficient *** the present investigation,Co-Fe-Ga-NiZn(CFGNZ)high entropy alloy(HEA)has been utilized as a low-cost electrocatalyst for ***,after cyclic voltammetry activation,CFGNZ-nanoparticles(Nps)are covered with oxidized surface and form high entropy(oxy)hydroxides(HEOs),exhibiting a low overpotential of 370 mV to achieve a current density of 10 mA/cm^(2)with a small Tafel slope of 71 mV/*** alloy has higher electrochemical stability in comparison to state-of-the art RuO2 electrocatalyst as no degradation has been observed up to 10 h of *** electron microscopy(TEM)studies after 10 h of long-term chronoamperometry test showed no change in the crystal structure,which confirmed the high stability of *** density functional theory(DFT)based calculations show that the closeness of d(p)-band centers to the Fermi level(EF)plays a major role in determining active *** work highlights the tremendous potential of CFGNZ HEA for OER,which is the primary reaction involved in water splitting.

关键词： high entropy alloy cyclic voltammetry activation oxygen evolution reaction electrocatalyst nanocrystalline catalyst

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