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21.
Tumuluru Jaya Shankar Shahab Sokhansanj Sukumar Bandyopadhyay A. S. Bawa 《Food and Bioprocess Technology》2010,3(4):481-490
In the present study, response surface method (RSM) and genetic algorithm (GA) were used to study the effects of process variables
like screw speed, rpm (x
1), L/D ratio (x
2), barrel temperature (°C; x
3), and feed mix moisture content (%; x
4), on flow rate of biomass during single-screw extrusion cooking. A second-order regression equation was developed for flow
rate in terms of the process variables. The significance of the process variables based on Pareto chart indicated that screw
speed and feed mix moisture content had the most influence followed by L/D ratio and barrel temperature on the flow rate. RSM analysis indicated that a screw speed > 80 rpm, L/D ratio > 12, barrel temperature > 80 °C, and feed mix moisture content > 20% resulted in maximum flow rate. Increase in screw
speed and L/D ratio increased the drag flow and also the path of traverse of the feed mix inside the extruder resulting in more shear.
The presence of lipids of about 35% in the biomass feed mix might have induced a lubrication effect and has significantly
influenced the flow rate. The second-order regression equations were further used as the objective function for optimization
using genetic algorithm. A population of 100 and iterations of 100 have successfully led to convergence the optimum. The maximum
and minimum flow rates obtained using GA were 13.19 × 10−7 m3/s (x
1 = 139.08 rpm, x
2 = 15.90, x
3 = 99.56 °C, and x
4 = 59.72%) and 0.53 × 10−7 m3/s (x
1 = 59.65 rpm, x
2 = 11.93, x
3 = 68.98 °C, and x
4 = 20.04%). 相似文献
22.
23.
In this study, we report a novel procedure for fabricating internally tapered capillary columns suitable for the coupling of capillary electrochromatography (CEC) to electrospray mass spectrometry (ESI-MS). The internal tapers were prepared by slowly heating the capillary end in a methane/O2 flame. Due to continuous self-shrinking of the inner channel of the capillary, the inside diameter of the opening was reduced to 7-10 microm. The procedure is easy to handle, with no requirement for expensive equipment as well as elimination of problematic grinding of the tip. Several advantages of these new internal tapers, as compared to using externally tapered columns, are described. First, the problems of poor durability and tip breakage associated with external tapering were successfully overcome with the internal taper. A comparison of the online CEC/ESI-MS between external versus internal tapers showed that the latter provides enhanced electrospray stability, resulting in significantly lower short-term noise and very short-term noise values. In turn, the more rugged design of internal tapers allows performing CEC/MS utilizing a harsh polar organic mobile phase, which was not previously successful using an external taper due to higher operating current and electrospray arcing. Next, data on the reproducibility of the internally tapered CEC/MS column using warfarin and beta-blockers as model analytes are presented. For example, when comparing the reproducibility for separation of warfarin under reversed-phase conditions, the internal taper demonstrated superior intraday % RSD (1.6-3.4) as compared to the external taper intraday % RSD (5-6). Last, the applicability of performing quantitative CEC/MS with internally tapered capillaries is demonstrated for simultaneous enantioseparation of beta-blockers. Impressive quantitative results include good linearity of calibration curves (e.g., R2 = 0.9940-0.9988) and limit of detection as low as 30 nM. The sensitive detection of a minor impurity of one enantiomer at the 0.1% level in a major chiral entity buttresses the suitability of compliance with FDA guidelines. 相似文献
24.
Ali Aakash Nasir Muhammad Ali Khalid Muhammad Yasir Nauman Saad Shaker Khubab Khushnood Shahab Altaf Khurram Zeeshan Muhammad Hussain Azhar 《Journal of Mechanical Science and Technology》2019,33(9):4217-4226
Journal of Mechanical Science and Technology - Natural fiber composites have great potential for reducing the product cost, lowering weight and enhancing renewability. Functionality and performance... 相似文献
25.
Dissociation of polar oil components in low salinity water and its impact on crude oil–brine interfacial interactions and physical properties 总被引:1,自引:0,他引:1
Despite many efforts into the study of fluids interaction in low salinity water flooding, they are not probing the basics of transport phenomena between the involved phases. This work is aimed to bring new understanding of fluid–fluid interaction during low salinity water flooding through a series of organized experiments in which a crude oil sample with known properties was kept in contact with different brine solutions of various ionic strengths. Measuring brine pH, conductivity and crude oil viscosity and density for a period of 45 days illustrates the strong effect of the contact time and ionic strength on the dissociation of polar components and physical properties of the crude oil and brine. Besides, the interfacial tension (IFT) measurements show that the interfacial interactions are affected by several competitive interfacial processes. By decreasing the ionic strength of the brine, the solubility of naphthenic acids in the aqueous solution increases, and hence, the conductivity and the pH of the aqueous phase decrease. To verify this important finding, UV–Vis spectroscopy and 1H NMR analysis were also performed on aged brine samples. Notably, there is an ionic strength of brine in which the lowest IFT is observed, while the other physical properties are remained relatively unchanged. 相似文献
26.
Gholam Hossein Majzoobi Shahab H. Amini Nejad Seyed Ali Reza Sabet 《Polymer Engineering and Science》2019,59(8):1636-1647
Strain rate has significant effect on mechanical behavior of the thermoset polymers. The rate sensitivity is more complicated for thermoset nanocomposites, which compose of two quite different types of materials. Nanofiller‐reinforced epoxy resin is widely used in the industry. In the present work, epoxy resin is reinforced by 0.05 to 0.7 wt% nanographene oxide (GO). The strain rate sensitivity of the fabricated nanocomposites is investigated through compressive test carried out at the strain rates of 0.001–1,900 s?1. The stress–strain curves of the nanocomposites indicated considerable difference between the low‐strain and high‐strain‐rate responses of the specimens. The results showed that the compressive strength of the nanocomposites was improved by more than 100% at high strain rates with respect to the low strain rates. Also, the addition of nano‐GO had influence on compressive strength enhancement but not as significant as the effect of strain rate. It was observed that the effect of GO was less important for higher strain rates. The experimental compressive strength and modulus of elasticity of the nanocomposites were casted in empirical relations for low and high strain rates for various filler weight percentages. Scanning electron microscopy was also used to examine the quality of GO dispersion. POLYM. ENG. SCI., 59:1636–1647 2019. © 2019 Society of Plastics Engineers 相似文献
27.
Taj M. Khan Shahab Ud-Din Khan Salah Ud-Din Khan Ashfaq Ahmad Shahab Ahmed Abbasi Eid Muhammad Khan Sam Mehigan 《国际能源研究杂志》2020,44(14):11443-11452
For the fast uptake into industrial applications, the further development of robust methods of nanomaterials, which are inexpensive and simultaneously technologically feasible, is one of the major key factors. A newly introduced atmospheric pulsed laser deposition method, based on a flowing gas approach, was used for plasmonic metal nanoparticle (NP) film of silver. Contrary to vacuum, in this method, the ambient air restricts expansion of the ablation plume within 1 to 3 mm above the target surface. These sets constrain on the formation of NP film close to the ablation spot. For deposition on a widely spaced surface, ablation material was entrained in a flow of argon, supplied at ~32 ms−1, and effectively delivered to the substrate at ~20 ms−1. The films produced were crystalline and particulate in nature, showing spectral plasmonic feature of surface plasmon resonance in the visible region. The film was directly tested in surface-enhanced Raman spectroscopy for chemical detection of crystal violet; the film with large particulates and aggregated crystallites was well-performed, showing enhanced Raman signals and detection sensitivity. Certainly, flowing gas atmospheric pulsed laser deposition seems a fast alternative to vacuum-pulsed laser deposition but needs further investigations to bring it in the industry for applications in sensor, catalysis, solar cell, and coating technology. 相似文献
28.
The phenomena of spontaneous combustion and thermal runaway in wood pellets storage were investigated using lab-scale experiments in the temperature range of 100–200 °C. The critical temperatures were determined for four sizes of reactors. The kinetic parameters of the self-heating were determined using three methods, the Frank-Kamenetskii's method, crossing point method, and numerical curve fitting method. Mean values of activation energy (E) of 78.7 ±0.8 kJ/mol and self-heating rate constant (∆ rhA) of (4.22 ±2.5) × 10 6 kJ/(kg s) were obtained for four type of wood pellets (made from whitewood) samples from different pellet producers in British Columbia. Finally, a two-dimensional numerical model was developed to predict the temperature development during self-heating and the critical temperature for known sizes of reactors. 相似文献
29.
The way towards generating a website front end involves a designer settling on an idea for what kind of layout they want the website to have, then proceeding to plan and implement each aspect one by one until they have converted what they initially laid out into its Html front end form, this process can take a considerable time, especially considering the first draft of the design is traditionally never the final one. This process can take up a large amount of resource real estate, and as we have laid out in this paper, by using a Model consisting of various Neural Networks trained on a custom dataset. It can be automated into assisting designers, allowing them to focus on the other more complicated parts of the system they are designing by quickly generating what would rather be straightforward busywork. Over the past 20 years, the boom in how much the internet is used and the sheer volume of pages on it demands a high level of work and time to create them. For the efficiency of the process, we proposed a multi-model-based architecture on image captioning, consisting of Convolutional neural network (CNN) and Long short-term memory (LSTM) models. Our proposed approach trained on our custom-made database can be automated into assisting designers, allowing them to focus on the other more complicated part of the system. We trained our model in several batches over a custom-made dataset consisting of over 6300 files and were finally able to achieve a Bilingual Evaluation Understudy (BLEU) score for a batch of 50 hand-drawn images at 87.86% 相似文献
30.
Abdul Waheed Naila Habib Khan Mahdi Zareei Shahab Ul Islam Latif Jan Arif Iqbal Umar Ehab Mahmoud Mohamed 《计算机、材料和连续体(英文)》2021,66(1):359-376
Congestion control is one of the main obstacles in cyberspace traffic.
Overcrowding in internet traffic may cause several problems; such as high packet
hold-up, high packet dropping, and low packet output. In the course of data transmission for various applications in the Internet of things, such problems are usually
generated relative to the input. To tackle such problems, this paper presents an analytical model using an optimized Random Early Detection (RED) algorithm-based
approach for internet traffic management. The validity of the proposed model is
checked through extensive simulation-based experiments. An analysis is observed
for different functions on internet traffic. Four performance metrics are taken into
consideration, namely, the possibility of packet loss, throughput, mean queue length
and mean queue delay. Three sets of experiments are observed with varying simulation results. The experiments are thoroughly analyzed and the best packet dropping operation with minimum packet loss is identified using the proposed model. 相似文献