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31.
This paper studies the effect of the number of component stations (parallelism), work transfer, processing time distributions, buffers and buffer allocation schemes on throughput and interdeparture time variability of assembly systems. As an alternative to work transfer, variability transfer is introduced and its effectiveness is assessed. Previous research has indicated that the optimal throughput displays an anomaly at certain processing time distributions and, this phenomenon is now thoroughly analyzed and the underlying details are uncovered. This study also yields several new findings that convey important practical implications. 相似文献
32.
Semra Turan Ihsan Karabulut Halil Vural 《Journal of the science of food and agriculture》2007,87(1):90-97
The oxidative stability of structured lipids (SLs) synthesised by specific sn‐1,3‐lipase catalysed interesterification of soybean oil (SBO) with caprylic acid (CA) in a stirred batch reactor was studied. SLs contained considerable amounts of tocopherol (TOH) isomers, although they lost almost 25% of endogenous TOHs during production. The effects of the addition of different TOH homologues (α, β, γ, δ), ascorbyl palmitate (AP, 200 ppm), lecithin (Le, 1000 ppm), butylated hydroxytoluene (BHT, 100 ppm) and butylated hydroxyanisole (BHA, 100 ppm) on the oxidative stability of SLs were investigated. Induction time (IT) of SBO, determined by the Rancimat method, decreased from 8.4 to 5.8 h at 110 °C after the modification. On the other hand, purified SLs and purified SBO had the same IT due to the tocopherol reduction during silica purification. No significant difference was observed between IT of SLs and SLs plus different α‐tocopherol concentrations (50, 100, 150, 200, 300, 500 and 1000 ppm) (P > 0.05). However, the addition of Le and/or AP significantly improved oxidative stability of purified SLs and SBO. The ternary blend containing δ‐TOH, AP and Le had higher IT than ternary blends of α‐TOH, β‐TOH or γ‐TOH. Furthermore, ternary blend containing BHA, AP and Le had higher IT than ternary blends of BHT, AP and Le. In addition, there was an increase in peroxide value (PV), conjugated diene (CD) content and p‐anisidine value (AV) during oxidation of oils at 60 °C. Antioxidant mixtures of α‐TOH (50 ppm) and δ‐TOH (500 ppm) with AP and Le decreased PV, CD and AV effectively. Copyright © 2006 Society of Chemical Industry 相似文献
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34.
Ayesha Kausar 《Bulletin of Materials Science》2014,37(4):917-923
A new aromatic azo-polymer, poly(thiourea-azo-sulfone), has been synthesized using 1-(4-thiocarbamoylaminophenylsulfonylphenyl)thiourea and diazonium salt solution. Conducting and thermally stable rubbery blends of poly(styrene-block-butadiene-block-styrene) (SBS) triblock copolymer and poly(thiourea-azo-sulfone) (PTAS) were produced by solution blending technique. PTAS possessed fine solubility in polar solvents and high molar mass 63 × 103 g moL?1. Microscopic analysis on SBS/PTAS blends revealed good adhesion between the two polymers without macro phase separation. Electrical conductivity measurement recommended that blending of SBS with 60% PTAS was sufficiently conducting 1.43 S cm?1. A relationship between PTAS loading and thermal stability of blends was observed. With the increasing PTAS content, 10% gravimetric loss was increased from 481 to 497 °C, while glass transition improved from 123 to 136 °C (better than neat SBS but lower than PTAS). The blends also established higher tensile strength (52.40–59.96 MPa) relative to SBS. Fine balance of properties renders new SBS/PTAS, potential engineering plastics for a number of aerospace relevance. 相似文献
35.
Muhammad Issa Khan Muhammad Sajid Arshad Faqir Muhammad Anjum Ayesha Sameen Aneeq-ur-Rehman Waqas Tariq Gill 《Food research international (Ottawa, Ont.)》2011,44(10):3125-3133
Consumers believe that foods are associated directly to their health. Today foods are not only used to satisfy our hunger but also to provide indispensible nutrients for humans and these nutrients having the health benefits regarding in controlling the diseases. The market for functional foods has seen a sharp rise in demand in the recent years. This has driven researchers to multiply their efforts in producing functional meat products also. Feed manipulation and post-mortem modification of meat coupled with enrichment of bioactive compounds are gaining importance. This review discusses the candidate ingredients and strategies, utilized in crafting such functional meat products, and the notable developments and commercial successes in functional meat industry. Dry fermented sausages meet the conditions required to carry viable probiotic microbes. This article enlists various microorganisms that are being commercially used in functional food products and potential bacteria for probiotic sausage production. 相似文献
36.
Caumes JP Younus A Salort S Chassagne B Recur B Ziéglé A Dautant A Abraham E 《Applied optics》2011,50(20):3604-3608
A monochromatic millimeter-wave imaging system coupled with an infrared temperature sensor has been used to investigate historic objects preserved at the Museum of Aquitaine (France). In particular, two-dimensional and three-dimensional analyses have been performed in order to reveal the internal structure of nearly 3500-year-old sealed Egyptian jars. 相似文献
37.
In 4 experiments, infants aged 8 to 12 months were tested on A not B search tasks, and nonsearch A not B tasks following the violation-of-expectation paradigm. A 1-location task and 2 control tasks were also conducted. In the nonsearch tasks, a toy was hidden in A, moved to B, and retrieved after a delay from either A (impossible) or B (possible). Results showed significantly longer looking times at impossible events, indicating some memory for where the object was hidden and an expectation of where it should be found. This effect occurred at delays at which infants made the A not B error when searching, and at a longer delay of 15 s. The results showed clearly that infants have some memory for the object's location, even at delays at which they search at the incorrect location. Discussion centers on how these results are accounted for within explanations of the A not B error. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
38.
Ciçek I Bozkurt A Karaman M 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2005,52(12):2235-2241
Integration of front-end electronics with 2D capacitive micromachined ultrasonic transducer (CMUT) arrays has been a challenging issue due to the small element size and large channel count. We present design and verification of a front-end drive-readout integrated circuit for 3D ultrasonic imaging using 2D CMUT arrays. The circuit cell dedicated to a single CMUT array element consists of a high-voltage pulser and a low-noise readout amplifier. To analyze the circuit cell together with the CMUT element, we developed an electrical CMUT model with parameters derived through finite element analysis, and performed both the pre- and postlayout verification. An experimental chip consisting of 4 X 4 array of the designed circuit cells, each cell occupying a 200 X 200 microm2 area, was formed for the initial test studies and scheduled for fabrication in 0.8 microm, 50 V CMOS technology. The designed circuit is suitable for integration with CMUT arrays through flip-chip bonding and the CMUT-on-CMOS process. 相似文献
39.
Saira Jabeen Sagheer Gul Ayesha Kausar Bakhtiar Muhammad Muhammad Farooq 《Polymer-Plastics Technology and Engineering》2019,58(4):427-442
A facile route was adopted to blend the matrix. The PMMA/PEG blend was reinforced with three types of nanofillers, i.e., pristine MWCNT (P-CNT), amine functionalized MWCNT (PDA-EA-CNT) and nanobifiller i.e. nanodiamond functional MWCNT (PDA-EA-CNT-ND) to yield three different types of nanocomposites i.e. PMMA/PEG/P-CNT, PMMA/PEG/PDA-EA-CNT and PMMA/PEG/PDA-EA-CNT-ND. These nanocomposites were reinforced with nanofiller loading (1 wt. %, 3 wt. %, 5 wt. %, 10 wt. %, 30 wt. % and 50 wt. %) by solution casting method. Structure of composite and nanofillers was confirmed by FTIR. FESEM imaging revealed that nanocomposites have micro porous morphology. At high magnification, distribution of functionalized CNT/ND appears to be protruding out of the polymeric matrix. The TGA result suggests that the thermal stability of the nanocomposites was enhanced in comparison to PMMA due to grafting of filler molecules with PMMA/PEG macromolecules. The DTG results showed that the bifiller nanocomposites (PMMA/PEG/PDA-EA-CNT-ND) exhibited improved thermal stability with Tmax (431°C) as compared to P-CNT and amine functionalized CNT (PMMA/PEG/PDA-EA-CNT) with Tmax of 395°C and 418°C respectively. XRD results showed fine interaction between filler and the polymeric matrix. As the filler loading was increased the composites showed pronounced XRD peak at 25.9°, corresponding to (002) reflection of nanotubes. Significant improvement in the mechanical properties of composites was recorded with the reinforcement of fillers as compared to the neat matrix. The most significant improvement in tensile strength and elastic modulus was observed for the bifiller nanocomposites with 5 wt. % PDA-EA-CNT-ND. They showed a tensile strength and elastic modulus of 29.9 MPa and 1474.31 MPa respectively as compared to amine functionalized CNT with tensile strength (25.7) and elastic modulus (1466.99 MPa)and P-CNT with tensile strength(25 MPa) and elastic modulus (1155.75 MPa). 相似文献
40.