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The purpose of the present study was to reduce the cost and increase the efficiency of biodiesel production by reactive extraction (in situ) of Jatropha seeds. Oil from the seeds was extracted and reacted in a single step. Experimental studies have been carried out to maximize the yield of biodiesel by varying the reaction parameters viz. seed size (<0.85 mm to >2.46 mm), seed/solvent ratio (w/w) (1:2.6–1:7.8) and catalyst concentration (0.05–0.1 M). Under the optimized conditions: seed size (>2.46 mm), seed/solvent ratio (w/w) (1:7.8), catalyst concentration (0.1 M) and reaction time 1 h, approximately 98% conversion to biodiesel was achieved meeting International (ASTM) as well as National (BIS) specifications. The results were supported by HPLC analysis.  相似文献   
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Fused filament fabrication (FFF) has been widely used to develop prototypes as well as functional parts owing to its capability for creating parts with complex geometries in a short time without the specific requirement of tooling. The mechanical properties of parts produced by FFF exhibit 70%-80% of the mechanical properties of parts produced by injection molding. The mechanical properties of FFF-produced parts are primarily dependent on the selection of various process variables. The mechanical properties of the part can be enhanced through the proper selection of process variables. In the present experimental investigation, the effects of the process variables, viz. raster angle, layer height, and raster width on the flexural properties of FFF-printed polylactic acid (PLA) is studied. The result shows that flexural strength is primarily influenced by layer height followed by raster angle. The sample printed with 100-μm layer height and 0° raster angle exhibits a higher tensile strength. Further, the microscopic examination of the deformed specimen is performed to understand the mode of failure. Specimens printed at different raster angles show different modes of failure.The full text can be downloaded at https://link.springer.com/article/10.1007/s40436-018-0237-6  相似文献   
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The study gives an insight into the effect of low frequency ultrasonic enhancement of solvent extraction on the quality of non-edible oils (Jatropha and Pongamia as model seed varieties) in comparison to conventional methods of extraction i.e. direct reflux or soxhlet extraction using hexane. A series of experiments have been carried out to study the effect of variables; solute to solvent ratio (1:2.5-1:10) and reaction time (30 s-60 min) on the yield of oil. The quality of oil extracted by different methods have been assessed by determining the acid value of oil by ASTM D-974/04 method, a measurement of triglyceride and fatty acid degradation, by the presence of phorbol esters in Jatropha curcas and phenolic compounds in Pongamia oil analyzed using HPLC. Under optimized conditions solute to solvent ratio of 1:10 (w/v), 3 min extraction time yields > 95% pure oil having < 1% FFA in Jatropha curcas and 30 s extraction time in Pongamia seed yields oil with less than 2% FFA in comparison to conventional method of extraction in 16 h.  相似文献   
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Carbon microcoils are generally prepared by catalytic chemical vapor deposition of acetylene, using Ni as the catalyst and thiophene as the promoter. In this work, a new catalyst has been developed on purpose to avoid the introducing of noxious and unpleasant thiophene during the reaction process. The products obtained at temperature of 740 degrees C were pure, regular and had perfect morphology. Scanning electron microscopy and Raman spectroscopy were employed to characterize the asprepared carbon microcoils.  相似文献   
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Karim SA  Porwal K  Kumar S  Singh VK 《Meat science》2007,76(3):395-401
The study was conducted on 6-month-old finisher lambs of the Kheri breed raised under extensive range management (G1), grazing with ad libitum concentrate supplementation (G2) or intensive feeding (G3) to assess dressing yield, cutability of standard cuts, composition of the carcass and the efficiency of mutton production from the three defined systems. The weaning weight of the lambs in the three groups was similar while the finishing weight, total body weight gain in the experiment, average daily gain and the percent feed conversion efficiency were higher (P<0.01) in G2 and G3 than G1. The pre slaughter weight (PSW), empty live weight (ELW), hot carcass weight and hot carcass weight with edible offal was higher (P<0.01) in G2 and G3 fed on a high plane of nutrition than G1 raised under extensive range management. The dressing percent in terms of live weight (LW) and empty live weight (ELW) was also higher in G2 and G3 than G1. The loin eye area as an index of muscle growth was also higher in G2 and G3 than G1. Although the weights of standard cuts were generally higher in G2 and G3 due to higher PSW, as proportions of half carcass they were similar in the three groups, except the rack cut, which was higher in G2 and G3. The cut proportions pooled for the three groups averaged 33.2%, 12.3%, 13.3%, 24.9% and 16.3% of half carcass for leg, loin, rack, neck and shoulder and breast and fore shank, respectively. The depot fat (Caul and kidney fat) accretion was higher in G2 and G3 than G1. The composition of the half carcass indicated that lean percent was higher (P<0.01) in G1 and G2 than G3 while sub cutaneous and intra muscular fat content were generally higher (P<0.01) in G2 and G3 and KOH bone percent was higher (P<0.05) in G1 and G2 than G3. The results indicated that the growth performance was better, feed conversion efficiency, carcass yield and dressing percentage higher in lambs maintained under grazing with supplementation and intensive feeding than extensive range management. The carcass separable fat content was 8% under extensive range management while it was 12% and 16% in semi intensive and intensive system of feeding management indicating that the carcass was of acceptable quality. The loin eye area reflected the trends of pre slaughter weight and was higher in intensive and semi intensive than extensive range management.  相似文献   
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Wireless Personal Communications - An inherent disadvantage of a Microstrip Patch Antenna (MPA) is its narrow bandwidth and low gain. There are various techniques in the market that either enhances...  相似文献   
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Multidimensional Systems and Signal Processing - In this paper, we consider the order estimation problem of a 2-dimensional complex superimposed exponential signal model in presence of additive...  相似文献   
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