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101.
Zachary Welsh Matthew J. Simpson Md Imran H. Khan M. A. Karim 《Comprehensive Reviews in Food Science and Food Safety》2018,17(5):1293-1308
Plant‐based food materials are mostly porous in nature and heterogeneous in structure with huge diversity in cellular orientation. Different cellular environments of plant‐based food materials, such as intercellular, intracellular, and cell wall environments, hold different proportions of water with different characteristics. Due to this structural heterogeneity, it is very difficult to understand the drying process and associated morphological changes during drying. Transport processes and morphological changes that take place during drying are mainly governed by the characteristics of and the changes in the cells. Therefore, to predict the actual heat and mass transfer process that occurs in the drying process and associated morphological changes, development of multiscale modeling is crucial. Multiscale modeling is a powerful approach with the ability to incorporate this cellular structural heterogeneity with microscale heat and mass transfer during drying. However, due to the huge complexity involved in developing such a model for plant‐based food materials, the studies regarding this issue are very limited. Therefore, we aim in this article to develop a critical conceptual understanding of multiscale modeling frameworks for heterogeneous food materials through an extensive literature review. We present a critical review on the multiscale model formulation and solution techniques with their spatial and temporal coupling options. Food structure, scale definition, and the current status of multiscale modeling are also presented, along with other key factors that are critical to understanding and developing an accurate multiscale framework. We conclude by presenting the main challenges for developing an accurate multiscale modeling framework for food drying. 相似文献
102.
Awais Khatri Iftikhar Ali Sahito Farooq Ahmed Imran Khatri 《Journal of Natural Fibers》2018,15(3):344-352
This paper discusses relation between fiber quality parameters and yarn quality, presenting results of the quality assessment of Pakistan’s five popular cotton varieties. Abadgar-901 was found to have highest effective length followed by Tarzen-1 when compared to other fibers studied and the Sattari showed the least effective length. Whereas, Tarzen-1 showed highest tenacity, Sindh-1 was second to that, yet Nayab-78 showed the least strength of the studied cotton fibers. Further, it was also found that except Nayab-78, all the other cotton varieties were found to have fineness value of premium cotton standards, however, Nayab proved to be a coarse fiber, Sindh-1 was finest fiber of them all. Moreover, Sattari was found to be the whitest in color when measured for CIE and Berger whiteness index, Nayab-78 followed it just after and the Abadgar proved to be the least white compared to the studied cotton varieties. 相似文献
103.
M. M. Quazi M. Ishak A. Arslan M. Nasir Bashir Imran Ali 《Journal of Adhesion Science and Technology》2018,32(6):625-641
This study highlights the scratch adhesion failure characterization and tribo-mechanical properties of physical vapor deposited (Cr, Ti) N coating on AA7075-T6 by using magnetron-sputtering technique. The surface morphology, microstructure and chemical composition of CrTi/CrTiN film were inspected by an optical microscope, scanning electron microscope (SEM) incorporated with energy dispersive X-ray spectroscopy (EDX) in addition to focused ion beam milling. The coating to substrate critical load of about 1261 mN was obtained, by employing coating deposition parameters of; DC power (300 W, RF power (200 W)), temperature (300 °C) and nitrogen flow rate (6%). Failure adhesion characteristics exhibited initial arc-tensile cracking followed by chipping and spallation that led to complete coating failure at Lc3. The tribo-mechanical aspects were evaluated by a pin-on-plate reciprocating testing unit, which showed a lower friction coefficient of 0.36 for CrTiN as compared with 0.43 for AA7075-T6. Subsequently, the wear depth was also reduced from 9.5 to 5.9 μm. It was revealed that the wear mechanism for AA7075-T6 was extensive deformation, abrasion and delamination, while the CrTiN exhibited slightly oxidative abrasive wear mode. 相似文献
104.
Muhammad Ali Raza Ling Yang Feng Wopke van der Werf Gao Ren Cai Muhammad Hayder Bin Khalid Nasir Iqbal Muhammad Jawad Hassan Tehseen Ahmad Meraj Muhammd Naeem Imran Khan Sana ur Rehman Muhammad Ansar Mukhtar Ahmed Feng Yang Wenyu Yang 《Food and Energy Security》2019,8(3)
Planting arrangements affect radiation use efficiency (RUE) and competitiveness of intercrop species in intercropping systems. Here, we reveal that narrow‐wide‐row planting arrangement in maize‐soybean relay‐intercropping system increases the dry matter and competitiveness of soybean, increased the RUE of maize and soybean, and compensates the yield loss of maize by substantially increasing the yield of soybean. In this field study, maize was planted with soybean in different planting arrangements (P1, 20:180, P2, 40:160; P3, 60:140, and P4, 80:120) of relay intercropping, all the relay‐intercropping treatments were compared with sole crops of maize (SM) and soybean (SS). Results showed that P1 improved the total RUE 3.26 g/MJ (maize RUE + soybean RUE) of maize and soybean in relay‐intercropping system. Compared to P4, treatment P1 increased the soybean competition ratio (CR) values (by 55%) but reduced the maize CR values (by 29%), which in turn significantly improved the yield of soybean by maintaining the maize yield. Generally, in P1, soybean produced 82% of SS yield, and maize produced 88% of SM yield, and it achieved the land equivalent ratio of 1.7. These results suggest that by maintaining the appropriate planting distances between maize and soybean we can improve the competitiveness and yield of intercrop species in relay‐intercropping system. 相似文献
105.
Muhammad Sajid Arshad Muhammad Imran Aftab Ahmed Muhammad Sohaib Azmat Ullah Mehr un Nisa Gule Hina Waseem Khalid Hafiza Rehana 《Food Science & Nutrition》2019,7(11):3378-3390
The modern‐day review article is an exquisite attempt to demonstrate the extreme therapeutic potential of tamarind fruit (Tamarindus indica), particularly its pulp, seed, and leaf extract, against lifestyle‐related chronic disorders. The rapid transition in the diet patterns and also the varying lifestyle of the people has made its way forth, a momentous upsurge in a number of chronic as well as degenerative diseases. An excess of foods having functional and nutraceutical significance has come into view recently. These foods have emerged as effective therapeutical remedies against these disorders owing to their natural phytochemical constituents present in them, in abundance. Tamarindus indica serves as a proverbial herbal medicine in each and every part of the world that is known to mankind. Also, the tamarind kernel powder (TKP) is of immense commercial significance in some of the major, leading industries of the World. The derivation of an important gel‐forming substance (polysaccharide), named as “jellose,” from the decorticated seed kernels of tamarind fruit has led to the manufacture of pectin. It is used in industrial scale in the preparation of various products like jams, jellies, and most important in the preparation of cheese. It plays an evident role as a stabilizer of commercial significance, and it has also been greatly recommend by the scientists to be used as a potent ingredient in a range of pharmaceutical products. The leaves of tamarind plant are also used as part of the daily diet in several countries where they are readily consumed in fresh form and especially during drought season. 相似文献
106.
Qingwang Yuan Xiang Zhou Jinjie Wang Fanhua Zeng Kelvin D. Knorr Muhammad Imran 《American Institute of Chemical Engineers》2019,65(1):360-371
In miscible displacements encountered in enhanced oil recovery processes, the unfavorable viscosity contrast between injected solvent and oil usually leads to viscous fingering (VF), a hydrodynamic instability which may result in a lower sweep efficiency and oil recovery. This phenomenon can be observed in a wide range of flows in subsurface porous media. This study examined a simple cyclic time-dependent displacement rate and its effects on the onset and longer development of VF. It is found that such varying displacement rate can either stabilize or destabilize VF, depending on the cycle period, amplitude, and displacement scenarios. The most important mechanism is that such time-dependent rate can effectively change the competition between convection (destabilizing effect) and dispersion (stabilizing effect). This is different from the widely used constant injection rate where the flow instability is actually determined by the Peclet number and mobility contrast for a given scenario. This study therefore provided a new aspect to control VF, either enhance or reduce, with low additional costs. It is therefore both scientifically and practically important for a wide range of flows in subsurface porous media. © 2017 American Institute of Chemical Engineers AIChE J, 65: 360–371, 2019 相似文献
107.
Internet is playing a vital role in providing information to billions of people around the world. It is the fastest way to communicate information worldwide. Over the years, information technology has provided solutions to many problems in different domains of life. With the advent of cloud computing and the internet of things (IOT), most of these domains are now employing cloud networks to save resources and money. Cloud provides a platform to store and process information with minimal resources and investment. Due to the vast geographical distribution and large distances between the cloud networks and the end user nodes, transmission of data over cloud networks provides problems of latency and delay that can cause major hazards in applications that require real‐time processing. In order to analyze the issues related to slow/no response from Clouds, a case study based on a mock E‐poll held under the Election commission of Pakistan is analyzed, and a remedy to the latency experienced during the polling process has been suggested. It involves the use of the newly proposed Fog Computing Paradigm to allow fast processing of real‐time data. This paper provides a solution to latency issues in cloud networks by proposing an intelligent way of identifying which data can be processed on close‐proximity Fog networks and which can be sent to the cloud for bulk processing. The aim is to reduce the time consumed for real‐time processing over the traditional cloud setup. 相似文献
108.
Momin Khan Akhtar Nadhman Walayat Shah Imran Khan Masoom Yasinzai 《IET nanobiotechnology / IET》2019,13(5):477
This study was aimed to develop a self‐nanoemulsifying drug delivery system (SNEDDS) for amphotericin B (AmB) potential use in leishmaniasis through topical and oral routes. Two formulations, formulation A and formulation B (FA and FB) of AmB loaded SNEDDS were developed by mixing their excipients through vortex and sonication. The SNEDDS formulation FA and FB displayed a mean droplet size of 27.70 ± 0.5 and 30.17 ± 0.7 nm and zeta potential −11.4 ± 3.25 and −13.6 ± 2.75 mV, respectively. The mucus permeation study showed that formulation FA and FB diffused 1.45 and 1.37%, respectively in up to 8 mm of mucus. The cell permeation across Caco‐2 cells monolayer was 10 and 11%, respectively. Viability of Caco‐2 cells was 89% for FA and 86.9% for FB. The anti‐leishmanial activities of FA in terms of IC50 were 0.017 µg/ml against promastigotes and 0.025 µg/ml against amastigotes, while IC50 values of FB were 0.031 and 0.056 µg/ml, respectively. FA and FB killed macrophage harboured Leishmania parasites in a dose‐dependent manner and a concentration of 0.1 µg/ml killed 100% of the parasites. These formulations have the potential to provide a promising tool for AmB use through oral and topical routes in leishmaniasis therapy.Inspec keywords: nanomedicine, drops, microorganisms, electrokinetic effects, cellular biophysics, drug delivery systems, monolayers, drugs, diseasesOther keywords: self‐nanoemulsifying drug delivery system, topical routes, oral routes, SNEDDS formulation, mucus permeation study, cell permeation, leishmaniasis treatment, amphotericin B, zeta potential, Caco‐2 cell monolayer, vortex, sonication, droplet size, Caco‐2 cell viability, antileishmanial activity, promastigotes, amastigotes, Leishmania parasites 相似文献
109.
Zohaib Noor Mannal Noor Imran Khan Syed Allauddin Khan 《Microscopy research and technique》2020,83(3):310-317
The present study focused to elucidate the promising role of probiotics in the fish culture, by employing microscopic and biochemical parameters to rationalize the possible outcomes. After preliminary feeding trial histopathological analysis revealed clear and visible changes in the intestinal and liver cells of CTRL (control group) compared to probiotics supplemented group, the bacterial inoculations resulted in shorten and swelled villi, while liver kupffer cells increased many folds in the CTRL. Moreover, there was clear hypertrophy and lamellar fusion in the gills tissues examined under microscope. Furthermore, intriguing results were obtained, such as a substantial increase in the weight gain, specific growth rate (%BW/day), FCE%, survival%, and improved secretions of amylase, cellulase, and protease activities. Likewise, high crude protein, fats content, while low moisture and total Ash was noticed in EXP I (Probiotics supplemented) compared to CTRL. The microscopic and biochemical analysis disclosed the positive role of probiotics on the fish health, thus we suggest its supplementations in the fish diet. 相似文献
110.
Non-isothermal DSC thermograms were obtained for the ternary Se90Te10−xSnx (x = 2, 4, 6 and 8) chalcogenide glasses in order to determine the melting temperature Tm, glass transition temperature Tg, onset Tc and peak Tp temperatures of crystallization. These temperatures were utilized to investigate the thermal stability through the calculations of temperature difference (Tc − Tg), the glass transition activation energy Et, the parameter S and the average value of crystallization rate factor 〈Kp〉. In addition, the glass forming ability was estimated by the criteria of reduced glass transition temperature, Trg and Hruby parameter HR. The fragility index m for the present glasses was determined in order to see whether these materials are obtained from strong or fragile glass-forming liquid. Results reveal that, both thermal stability and glass forming ability exhibit a maximum at x = 4 at.% of Sn. Meanwhile, the prepared glasses were obtained from strong glass-forming liquid as evident from the fragility index calculations. The compositional dependence of the above parameters was discussed on the basis of Philips and Thorpe topological model and the critical composition occurs at an average coordination number 〈r〉 = 2.16 but not 2.40. This is due to the formation of iono-covallent bonds when the glass doped with heavy elements like Sn. 相似文献