81 research outputs found

    Ethnomedicinal wisdom of tribals of Mahur forest of Nanded district, Maharashtra, India.

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    Mahur range forest of Nanded district is rich in medicinal plants. In the present paper 25 plants species belonging to 25 genera and 20 families used in folk medicine has been documented. Due to poor condition of modern healthcare facilities and poverty the tribal people and rustics of the forest fully or partially depend on local medicinal plants. An attempt has been made to document traditional knowledge from tribal people, medicinal practitioner, traditional healers medicinemen, herbal venders, rustics etc. The plants were enumerated alphabetically along with botanical name, family and vernacular name.&nbsp

    Effects of ultrasound on polymeric foam porosity

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    A variety of materials require functionally graded cellular microstructures whose porosity is engineered to meet specific applications (e.g. mimic bone structure for orthopaedic applications; fulfil mechanical, thermal or acoustic constraints in structural foamed components, etc.). Although a huge variety of foams can be manufactured with homogenous porosity, there are no generic processes for controlling the distribution of porosity within the resulting matrix. Motivated by the desire to create a flexible process for engineering heterogeneous foams, the authors have investigated how ultrasound, applied during the formation of a polyurethane foam, affects its cellular structure. The experimental results demonstrated how the parameters of ultrasound exposure (i.e. frequency and applied power) influenced the volume and distribution of pores within the final polyurethane matrix: the data demonstrates that porosity (i.e. volume fraction) varies in direct proportion to both the acoustic pressure and frequency of the ultrasound signal. The effects of ultrasound on porosity demonstrated by this work offer the prospect of a manufacturing process that can adjust the cellular geometry of foam and hence ensure that the resulting characteristics match the functional requirements

    Document Classification using LSTM Neural Network

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    Document Classification is one of the most important topic in Computer Science as the number of electronic documents are increasingly very rapidly each day. Document classification is also known as Document Categorization. Classification is training of known labels to predict the unknown labels. It is the process of assigning a particular document to predefined categories.In this paper, we apply machine learning methods for classification of Documents. Recurrent Neural Networks of which LSTM is one of the most successful and have been developed for Controlling Robots, Natural Language Text Compression, Automatic Speech Recognition, Time Series Prediction, Handwriting Recognition and many more. LSTM can also be used for document classification. Document Classification includes text processing, feature extraction, feature vector construction and label prediction or final classification. Furthermore, we first try some data processing on 20 Newsgroup Dataset, and then we extract a features by using feature weighting and feature selection algorithms. The extracted features are then passed to the LSTM Neural network for future Label Predictions. Therefore, the documents are classified into different categories according to their context

    Ultrasound-assisted extraction of natural products

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    Ultrasound-assisted extraction (USAE) is an interesting process to obtain high valuable compounds and could contribute to the increase in the value of some food by-products when used as sources of natural compounds. The main benefits will be a more effective extraction, thus saving energy, and also the use of moderate temperatures, which is beneficial for heat-sensitive compounds. For a successful application of the USAE, it is necessary to consider the influence of several process variables, the main ones being the applied ultrasonic power, the frequency, the extraction temperature, the reactor characteristics, and the solvent-sample interaction. The highest extraction rate is usually achieved in the first few minutes, which is the most profitable period. To optimize the process, rate equations and unambiguous process characterization are needed, aspects that have often been lacking. © 2011 Springer Science+Business Media, LLC.The authors thank the Generalitat Valenciana for their financial support in project PROMETEO/2010/062 and the Caja de Ahorros del Mediterraneo for M.D. Esclapez's pre-doctoral grant.Esclapez Vicente, MD.; GarcĂ­a PĂ©rez, JV.; Mulet Pons, A.; CĂĄrcel CarriĂłn, JA.; Esclapez, MD. (2011). Ultrasound-assisted extraction of natural products. Food Engineering Reviews. 3(2):108-120. https://doi.org/10.1007/s12393-011-9036-6S10812032Abad Romero B, Bou-Maroun E, Reparet JM, Blanquet J, Cayot N (2010) Impact of lipid extraction on the dearomatisation of an Eisenia foetida protein powder. Food Chem 119:459–466Adewuyi YG (2001) Sonochemistry: environmental science and engineering applications. Ind Eng Chem Res 40:4681–4715Atchley AA, Crum LA (1988) Acoustic cavitation and bubble dynamics. 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Ultrasonics 44:539–543GarcĂ­a-PĂ©rez JV, GarcĂ­a-Alvarado MA, Carcel JA, Mulet A (2010) Extraction kinetics modeling of antioxidants from grape stalk (Vitis vinifera var. Bobal): Influence of drying conditions. J Food Eng 101:49–58GonzĂĄlez-GarcĂ­a J, SĂĄez V, Tudela I, DĂ­ez-Garcia MI, Esclapez MD, Louisnard O (2010) Sonochemical treatment of water polluted by chlorinated organocompounds. A review. Water 2:28–74Handa SS, Preet S, Khanuja S, Longo G, Rakesh DD (2008) Extraction Technologies for Medicinal and Aromatic Plants. United Nations Industrial Development Organization and the International Centre for Science and High Technology, TriesteHemwimol S, Pavasant P, Shotipruk A (2006) Ultrasound-assisted extraction of anthraquinones from roots of Morinda citrifolia. Ultrason Sonochem 13:543–548Hielscher (2011) Teltow http:// www.hielscher.com . Accessed 10 Jan 2011Hu Y, Wang T, Wang M, Han S, Wan P, Fan M (2008) Extraction of isoflavonoids from Pueraria by combining ultrasound with microwave vacuum. Chem Engin Process 47:2256–2261Ince NH, Tezcanli G, Belen RK, Apikyan PG (2001) Ultrasound as a catalyzer of aqueous reaction systems: the state of the art and environmental applications. Appl Catal B 29:167–176Jadhav D, Rekha BN, Gogate PR, Rathod VK (2009) Extraction of vanillin from vanilla pods: a comparison study of conventional soxhlet and ultrasound assisted extraction. J Food Eng 93:421–426Ji J-b, Lu X-h, Cai M-q, Xu C-c (2006) Improvement of leaching process of Geniposide with ultrasound. Ultrason Sonochem 13:455–462Kanthale PM, Gogate PR, Pandit AB, Wilhelm AM (2003) Mapping of an ultrasonic horn: link primary and secondary effects of ultrasound. Ultrason Sonochem 10:331–335Karki B, Lamsal BP, Jung S, van Leeuwen JH, Pometto AL III, Grewell D, Khanal SK (2010) Enhancing protein and sugar release from defatted soy flakes using ultrasound technology. J Food Eng 96:270–278Kardos N, Luche J-L (2001) Sonochemistry of carbohydrate compounds. Carbohydr Res 332:115–131Kotronarou A, Mills G, Hoffmann MR (1991) Ultrasonic Irradiation of para-Nitrophenol in Aqueous Solution. J Phys Chem 95:3630–3638Kuijpers MWA, Kemmere MF, Keurentjes JTF (2002) Calorimetric study of the energy efficiency for ultrasound-induced radical formation. Ultrasonics 40:675–678Leighton TG (2007) What is ultrasound? Prog Biophys Mol Biol 93:3–83Leonelli C, Mason TJ (2010) Microwave and ultrasonic processing: now a realistic option for industry. Chem Eng Process 49:885–900Li H, Pordesimo L, Weiss J (2004) High intensity ultrasound-assisted extraction of oil from soybeans. Food Res Int 37:731–738Liu J, Li J-W, Tang J (2010) Ultrasonically assisted extraction of total carbohydrates from Stevia rebaudiana Bertoni and identification of extracts. Food Bioprod Process 88:215–221Lianfu Z, Zelong L (2008) Optimization and comparison of ultrasound/microwave assisted extraction (UMAE) and ultrasonic assisted extraction (UAE) of lycopene from tomatoes. Ultrason Sonochem 15:731–737Liazid A, Schwarz M, Varela RM, Palma M, GuillĂ©n DA, Brigui J, MacĂ­as FA, Barroso CG (2010) Evaluation of various extraction techniques for obtaining bioactive extracts from pine seeds. Food Bioprod Process 88:247–252Londoño-Londoño J, Rodrigues de Lima V, Lara O, Gil A, Crecsynski Pasa TB, Arango GJ, Ramirez Pineda JR (2010) Clean recovery of antioxidant flavonoids from citrus peel: optimizing an aqueous ultrasound-assisted extraction method. Food Chem 119:81–87Lou Z, Wang H, Zhang M, Wang Z (2010) Improved extraction of oil from chickpea under ultrasound in a dynamic system. J Food Eng 98:13–18Louisnard O, GonzĂĄlez-GarcĂ­a J, Tudela I, Klima J, SĂĄez V, Vargas-HernĂĄndez Y (2009) FEM simulation of a sono-reactor accounting for vibrations of the boundaries. Ultrason Sonochem 16:250–259Luque de Castro MD, Priego-Capote F (2007) Analytical Applications of Ultrasound, Vol. 26, Techniques and Instrumentation in Analytical Chemistry. Elsevier Science, AmsterdamMa Y, Ye X, Hao Y, Xu G, Xu G, Liu D (2008) Ultrasound-assisted extraction of hesperidin from Penggan (Citrus reticulata) peel. Ultrason Sonochem 15:227–232Ma Y, Chen J-C, Liu Dong-Hong, Ye X-Q (2009) Simultaneous extraction of phenolic compounds of citrus peel extracts: effect of ultrasound. Ultrason Sonochem 16:57–62Makino K, Mossoba MM, Riesz P (1982) Chemical effects of ultrasound on aqueous solutions. Evidence for hydroxyl and hydrogen free radicals (.cntdot. OH and. cntdot. H) by spin trapping. 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    Ethnomedicinal plants and their utilization by tribals of Mahur range forest of Nanded district of Maharashtra, India

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    578-581The present paper deals with the observation of ethnomedicinal uses of plant wealth by Gond, Kolam, Pradhan, Naikde and Andh tribes of Mahur range forest of Nanded district. This range was selected for investigation, as the tribals of this area are mainly dependent upon the forest flora for their livelihood and use herbal medicines for curing the ailments and diseases. Altogether 25 plants were recorded which are used by tribal people in formulation of 32 different ethnomedicinal preparation for curing 24 different types of diseases and ailments. Many of these ethnomedicinal preparations are new. Among 32 ethnomedicinal uses 20 are administrated in the form of single drug for curing white discharge, dysentery, fever, cough, kidney stone, asthma, etc. The data of this study provide the botanical name, family, local name, part(s) used, mode of administration, etc. Some noteworthy plants which are used in curing the diseases are: Abelmoschus crinitus Wall., <i style="mso-bidi-font-style: normal">Crotalaria notonii Wight & Arn.,<i style="mso-bidi-font-style: normal"> Cyperus sanguinolentus Vahl., <span style="mso-bidi-font-weight: bold">Gloriosa superba Linn., Indigofera tinctoria Linn., <i style="mso-bidi-font-style: normal">Phyllanthus maderaspatensis Linn.,<b style="mso-bidi-font-weight: normal"> <i style="mso-bidi-font-style: normal">Desmodium velutinum (Willd.) DC., etc. </span

    Modeling aspects of dual frequency sonochemical reactors

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    The dual or multi-source irradiation with same or different operating frequency has proved to be a new dimension to the sonochemical reactors. In the present work, the model developed earlier [P.A. Tatake, A.B. Pandit, Modeling and experimental investigation into cavity dynamics and cavitational yield: influence of dual frequency ultrasound sources, Chem. Eng. Sci. 57 (2002) 4987] using Rayleigh-Plesset equation has been made more realistic by incorporating the effect of liquid phase compressibility. The aim has been to study the bubble dynamics under the influence of dual frequency acoustic field and explain the superiority of the same as compared to the single frequency irradiations. The effect of intensity and dual-frequency on the bubble dynamics and the conditions of the cavity collapse has been investigated. The numerical results have been compared with the previous experimental trends under similar operating conditions. The simple model developed in the present work seems to quite satisfactorily explain the experimental results obtained using dual frequency sonication system. Thus, the methodology adapted in the present work is a useful starting point for the modeling and designing large scale multiple frequency reactors. Recommendations have also been made for developing realistic bubble dynamics model which should help in optimization of multiple frequency sonochemical reactors

    Mapping of sonochemical reactors: review, analysis, and experimental verification

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    The erratic behavior of cavitational activity exhibited in a sonochemical reactor poses a serious problem in its design and scale-up. Several previous studies in the past dealt with mapping of sonochemical reactors, which have been critically analyzed and recommended for efficient scale-up strategies. There have been no efforts to link the primary effects (local pressure field) of ultrasound activity with the observed secondary effects (such as chemical reaction). In this work an ultrasonic horn (standard immersion-type reactor), and an ultrasonic bath (rectangular geometry with transducers located at the bottom in triangular pitch) reactors were mapped with the help of local pressure measurement (using a hydrophone), and liberated iodine was estimated using the Weissler reaction, and a quantitative relationship was established between the two. In estimating chemical reaction rates, the effect of microscopic variation in the type of microreactor used (test tube in this case) on the extent of degradation was also investigated. Measured local pressure pulses were used in theoretical simulations of bubble dynamics equations to check the type of cavitation taking place locally, and to estimate the possible collapse of the pressure pulse in terms of the maximum bubble size reached during the cavitation phenomena. A relationship also was established between observed iodine liberation rates and the maximum bubble size reached. The engineers can easily use these unique relationships in an efficient design, since the secondary effect can be directly quantified

    Mapping of an ultrasonic horn: link primary and secondary effects of ultrasound

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    The erratic behaviour of cavitational activity exhibited in a sonochemical reactor pose a serious problem in the efficient design and scale-up; thus it becomes important to identify the active and passive zones existing in the reactor so as to enable proper placement of the reaction mixtures for achieving maximum benefits. In the present work mapping of ultrasonic horn has been carried with the help of local pressure measurement using a hydrophone and estimation of amount of liberated iodine using the Weissler reaction and a quantitative relationship has been established. The measured local pressure pulses have been used in the theoretical simulations of the bubble dynamics equations to check the type of cavitation taking place locally and also estimate the possible collapse pressure pulse in terms of maximum bubble size reached during the cavitation phenomena. Relationship has been also established between the observed iodine liberation rates and the maximum bubble size reached. The engineers can easily use these unique relationships in efficient design, as the direct quantification of the secondary effect is possible
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