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Liao Xiufeng Khandelwal Manoj Yang Haiqing Koopialipoor Mohammadreza Murlidhar Bhatawdekar Ramesh 《Engineering with Computers》2020,36(2):499-510
Engineering with Computers - One of the important factors during drilling times is the rate of penetration (ROP), which is controlled based on different variables. Factors affecting different... 相似文献
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Rucha R. Joshi Mangesh Warthe Sharad Dwivedi Tapan Chakrabarti 《International journal of remote sensing》2013,34(24):9547-9558
Impact of anthropogenic activities has led to significant changes in riverbeds over a period of time. The objective of the study was to monitor the land use land cover (LULC) of Yamuna riverbed in Delhi and to assess the changes due to natural and anthropogenic activities. The maximum likelihood classification was carried out by using March 1977, April 1999, April 2002 and February 2009 imageries. An overall accuracy of LULC classification of 2009 imagery was around 88.6% based on ground truth data. A significant reduction in the main river course and increase in agricultural activities as well as built up were observed in remote sensing analysis as an outcome of riverbed encroachments. The changed scenario of riverbed not only stresses the riverine ecosystem but also jeopardizes the future consequences on river hydraulics. 相似文献
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Bamboo is considered to be an important biopolymer with useful applications in various fields including textiles. It is a renewable natural resource of cellulosic nature and it originates from grass family. It gives maximum biomass per unit area and time. In general, cellulosic fibres do not have acid dyeability as those of polyamide fibres. Hence, it is difficult to dye such fibres, unless modified, with acid dyes which are relatively cheaper than the direct class of dyes. In the current study, the bamboo rayon fabric was grafted with acrylamide using potassium persulphate (KPS) as an initiator. The grafting conditions were optimized in terms of temperature, time, initiator and monomer concentrations. The grafted product was characterized using FTIR, TGA, SEM and analyzed for textile properties like moisture regain and yellowness index. The ungrafted and grafted fabrics were dyed using acid dyes and tested for colour strength and fastness properties. An increase in the dyeability of the order of 150?C230% was observed on grafting of bamboo rayon. The distinct improvement in moisture regain of the grafted fabrics was also observed, which is due to increase in the polarity of the fibres. Hence, better comfort can be expected out of such fabrics during summer. The bamboo rayon which is otherwise not dyeable with acid dyes, can be rendered acid dyeable by grafting technique. 相似文献
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Mangesh G Kulkarni Ajay K Dalai Narendra N Bakhshi 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2006,81(12):1886-1893
Increasing percentage of green canola seed every year is a serious problem for canola growers. Chlorophyll content of this oil is very high, which makes it more susceptible to photo‐oxidation and ultimately the oxidation stability of the oil is very reduced. Hence green seed canola oil is underutilized for edible purposes. The present work is an attempt to produce high‐quality biodiesel from green seed canola oil and methanol, ethanol and various mixtures of methanol and ethanol using KOH as a catalyst. A mixture of alcohols improved the rate of reaction. After transesterification of green seed canola oil using KOH, the chlorophyll content of the oil was decreased substantially (from 22.1 ppm to 10.3 ppm). Characteristics of the esters prepared from green seed canola oil were well within the limits of ASTM standards. Lubricity of the green seed oil esters was excellent (20% decrease in wear scar area) when added at 1 vol% to the base fuel. Oxidation stability is crucial for long‐term storage of the fuel. Oxidation stability index (OSI) of green seed esters was 4.9 h at 110 °C, which is much less than the European Standard (6 h at 100 °C). The low oxidation stability of green seed esters is attributed to its higher chlorophyll (10.3 ppm) content. An attempt was also made to reduce the chlorophyll content of the oil before transesterification using activated carbon treatment, and it was observed that chlorophyll content was reduced from 22.1 to 2.2 ppm. Copyright © 2006 Society of Chemical Industry 相似文献
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Selegiline hydrochloride (SHCl), a monoamine oxidase B inhibitor, is used as an adjunct in the therapy of Parkinson’s disease. This study is concerned with the preparation and evaluation of mucoadhesive buccal tablet for controlled systemic delivery of SHCl. Buccal absorption of selegiline can bypass its first-pass metabolism and improve bioavailability accompanied by greatly reduced metabolite formation, which is potentially of enhanced therapeutic value in patients with Parkinson’s disease. Polycarbophil–cysteine (PCP–cys) conjugate, which is a thiolated derivative of the mucoadhesive polymer polycarbophil, was synthesized by 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide hydrochloride-mediated amide bond coupling. Tablets of SHCl based on native and thiolated polycarbophil were prepared. The prepared tablets were evaluated for drug content, swelling behavior, mucoadhesive strength, in vitro drug release, ex vivo permeation and in vitro cytotoxicity. PCP–cys tablets showed enhanced mucoadhesion and retarded drug release compared to polycarbophil tablets. Permeation data of SHCl from matrices prepared using the PCP–cys polymer revealed a significantly higher value of apparent permeability in comparison to polycarbophil, which supported the information in literature that thiolation imparts permeation enhancing properties to mucoadhesive polymers. In vitro cytotoxicity studies on PCP–cys using L-929 mouse fibroblast cell line indicated that conjugation with cysteine does not impart any apparent toxicity to polycarbophil. The results from the study indicate that the buccal delivery of SHCl using thiolated polycarbophil tablet could provide a way for improved therapy of Parkinson’s disease. 相似文献
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The main objective of this study was to determine the effect of intracrystalline and intercrystalline swelling agents and reactive dyes on the accessibility of cotton cellulose to commercial cellulase enzymes. Both types of swelling agents improved the accessibility, and intracrystalline swelling agents showed better results, as the accessibility to difficult‐to‐reach crystalline regions was increased. As expected, the reactive dyes inhibited the accessibility of the enzymes to some extent. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
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Shirale DJ Bangar MA Park M Yates MV Chen W Myung NV Mulchandani A 《Environmental science & technology》2010,44(23):9030-9035
We report development, characterization, and testing of chemiresistive immunosensors based on single polypyrrole (Ppy) nanowire for highly sensitive, specific, label free, and direct detection of viruses. Bacteriophages T7 and MS2 were used as safe models for viruses for demonstration. Ppy nanowires were electrochemically polymerized into alumina template, and single nanowire based devices were assembled on a pair of gold electrodes by ac dielectrophoretic alignment and anchored using maskless electrodeposition. Anti-T7 or anti-MS2 antibodies were immobilized on single Ppy nanowire using EDC-NHS chemistry to fabricate nanobiosensor for the detection of corresponding bacteriophage. The biosensors showed excellent sensitivity with a lower detection limit of 10(-3) plaque forming unit (PFU) in 10 mM phosphate buffer, wide dynamic range and excellent selectivity. The immunosensors were successfully applied for the detection of phages in spiked untreated urban runoff water samples. The results show the potential of these sensors in health care, environmental monitoring, food safety and homeland security for sensitive, specific, rapid, and affordable detection of bioagents/pathogens. 相似文献