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991.
Mohammad Usman Makeri Roselina Karim Mohamed Sabo Abdulkarim Hasanah Mohd Ghazali Mat Sahri Miskandar 《International Journal of Food Properties》2016,19(12):2769-2787
To explore possible food applications, the oxidative stability, antioxidants contents (tocopherols and tocotrienols), thermal properties, and solid fat content of winged bean oil were investigated along with soybean oil for comparison. Results showed that winged bean oil was significantly (p < 0.05) resistant to oxidation (27 h) compared to soybean oil (9 h) heated at 110oC for 32 h, due presumably to the presence of alpha tocotrienol and the high behemic acid content. The high content of tocopherols, 230 mg/100 g in soybean oil did not contribute much to its oxidation stability. At around 25oC, winged bean oil contained about 15% solid fat content with <1% in soybean oil. Soybean oil, however, had better levels of the omega-3 and omega-6 fatty acids with a ratio of 7.6:1, falling within the range of 5:1 and 10:1 recommended by the Food and Agriculture Organization/World Health Organization, when compared to winged bean oil having a ratio of 34.4:1. The positional fatty acids esterified as stearoyl, palmitoyl, behemoyl or lignoceroyl triacylglycerides species, PSP, PPP, PLB, POB and SSlg+PBP overwhelmed the unsaturated FAs of winged bean oil for free radical reaction and also conferred it high thermal conductivity. The high oxidative stability, solid fat content, and thermal conductivity of winged bean oil coupled with its crystalization characteristics confirmed it to be good material for frying and for making zero-trans-fat margarines and spreads. 相似文献
992.
Choubani Karim Author Vitae Zitouni Slim Author Vitae Safi Mohamed Jomâa Author Vitae 《Solar Energy》2010,84(1):24-31
Many natural systems such as oceans, lakes, etc.…, are influenced by the effect of double-diffusive convection. This phenomenon, which is a combination of heat and mass transfer, can destroy the stability of system-flows.In the case of solar ponds the middle layer, that is linearly stratified, acts as a thermal and mass insulator for the lower layer. This middle layer, called the Non-Convective Zone (NCZ), needs special care to avoid convection and to maintain its stability. In fact, due to an excess of heat stored, a thermal gradient occurs within the NCZ. A convective movement appears at the bottom of the stratified-layers and then grows to a double-diffusive convection movement. This movement transforms the stratified-layers into a well mixed layer, reducing the storage capacity of the pond.Laboratory small-scale pond and middle-scale outdoor solar ponds were designed and built to provide both quantitative data and to study the dynamic processes in solar ponds, including the behavior of the gradient zone.Particle Image Velocimetry (PIV) visualization-experiments carried out in the mechanical and energetic laboratory in the engineering school of Tunisia and experiments in the field showed that the instability of solar ponds could be limited by using porous media placed in the lower layer of the stratification. 相似文献
993.
Asif Karim Sagar E. Shirsath S.J. Shukla K.M. Jadhav 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2010,268(17-18):2706-2711
Ferrite of system, namely Ni1?xZnxFe2O4 with x = (0.0, 0.2, 0.4, 0.6, 0.8, 1.0), have been prepared by solid state reaction to investigate the effect of gamma rays irradiations using Co60 source on the cation distribution, structural and magnetic properties. The unirradiated and irradiated samples were then subjected to characterization techniques such as X-ray diffraction, magnetization and AC susceptibility. The results of these characterizations are found to be different for irradiated from that of the pristine sample. The modifications in respect of irradiated samples are explained in terms of the ion-induced disorder. The important result of γ-irradiation on the cation distribution, structural and magnetic properties is the change of ratio Fe2+/Fe3+. Possible reasons on the results are proposed. 相似文献
994.
Prevalence,antimicrobial resistance and genetic lineages of Enterococcus spp. from vegetable food,soil and irrigation water in farm environments in Tunisia
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995.
Mohammad Rajib Ricardo Martinez Mohammad Shuvo Hasanul Karim Diego Delfin Samia Afrin Gerardo Rodriguez Ramana Chintalapalle Yirong Lin 《International Journal of Applied Ceramic Technology》2016,13(1):125-132
Enhancing the performance of dielectric capacitors toward higher energy density and higher operating temperatures has been drawing increased interest. Therefore, in this investigation, research efforts were dedicated to the fabrication and characterization of nanocomposites in order to enhance the energy density at both room temperature and elevated temperature. The dielectric capacitors are fabricated using nanocomposites composed of BaTiO nanoparticles with polyimide (PI) matrix aiming at combining the high relative dielectric permittivity of the ceramic filler and the high breakdown strength of the polymeric matrix. Dielectric energy storage performance is assessed for nanocomposites with volume fractions ranging from 0 to 20% under operating frequency from 20 Hz to 1 MHz and temperatures ranging from 20 to 120C. It is observed that with the increase of temperature, the capacitance increased while the energy density slightly decreased but significantly higher than pure polymer samples. The highest energy density was found for BaTiO/PI nanocomposites with 20% volume fraction, 9.63 J/cm at 20C and 6.79 J/cm at 120C. Overall, testing results indicate that using nanocomposites of BaTiO/PI as a dielectric component shows promise for implementation to preserve high energy density values up to temperatures of 120C. 相似文献
996.
997.
Camille Jacques Mathias Chatelais Karim Fekir Adrien Brulefert Ilaria Floris 《International journal of molecular sciences》2022,23(4)
As a cytokine, gamma-interferon (IFN-γ) is considered a key player in the fine-tuned orchestration of immune responses. The extreme cellular sensitivity to cytokines is attested by the fact that very few of these bioactive molecules per cell are enough to trigger cellular functions. These findings can, at least partially, explain how/why homeopathically-prepared cytokines, and especially micro-immunotherapy (MI) medicines, are able to drive cellular responses. We focused our fundamental research on a unitary MI preparation of IFN-γ, specifically employed at 4 CH, manufactured and impregnated onto sucrose-lactose pillules as all other MI medicines. We assessed the IFN-γ concentration in the medium after dilution of the IFN-γ (4 CH)-bearing pillules and we evaluated in vitro drug responses in a wide range of immune cells, and in endothelial cells. Our results showed that IFN-γ (4 CH) stimulated the proliferation, the activation and the phagocytic capabilities of primary immune cells, as well as modulated their cytokine-secretion and immunity-related markers’ expression in a trend that is quite comparable with the well-recognized biological effects induced by IFN-γ. Altogether, these data provide novel and additional evidences on MI medicines, and specifically when active substances are prepared at 4 CH, thus suggesting the need for more investigations. 相似文献
998.
Chengqian Che Ruogu Lin Xiangrui Zeng Karim Elmaaroufi John Galeotti Min Xu 《Machine Vision and Applications》2018,29(8):1227-1236
Cellular processes are governed by macromolecular complexes inside the cell. Study of the native structures of macromolecular complexes has been extremely difficult due to lack of data. With recent breakthroughs in Cellular Electron Cryo-Tomography (CECT) 3D imaging technology, it is now possible for researchers to gain accesses to fully study and understand the macromolecular structures single cells. However, systematic recovery of macromolecular structures from CECT is very difficult due to high degree of structural complexity and practical imaging limitations. Specifically, we proposed a deep learning-based image classification approach for large-scale systematic macromolecular structure separation from CECT data. However, our previous work was only a very initial step toward exploration of the full potential of deep learning-based macromolecule separation. In this paper, we focus on improving classification performance by proposing three newly designed individual CNN models: an extended version of (Deep Small Receptive Field) DSRF3D, donated as DSRF3D-v2, a 3D residual block-based neural network, named as RB3D, and a convolutional 3D (C3D)-based model, CB3D. We compare them with our previously developed model (DSRF3D) on 12 datasets with different SNRs and tilt angle ranges. The experiments show that our new models achieved significantly higher classification accuracies. The accuracies are not only higher than 0.9 on normal datasets, but also demonstrate potentials to operate on datasets with high levels of noises and missing wedge effects presented. 相似文献
999.
An Adaptive Middleware for Context-Sensitive Communications for Real-Time Applications in Ubiquitous Computing Environments 总被引:1,自引:0,他引:1
Context-sensitivity is an important expected capability in applications in ubiquitous computing (ubicomp) environments. These applications need to use different contextual information from the user, host device, on board sensors, network, and the ambient environments to systematically adapt their actions. In addition, some context-sensitive applications may use specific contextual conditions to trigger impromptu and possibly short-lived interactions with applications in other devices. This property, referred to as context-sensitive or context-aware communications, allows applications to form short-range mobile ad hoc networks consisting of mobile and stationary devices, sensors, and other computing resources. Real-time applications, especially those having reactive behavior, running on embedded devices and requiring context-sensitive communications support, pose new challenges related to systematic representation of specific contexts, associations of contexts with real-time actions, timely context data collection and propagation, and transparent context-sensitive connection establishment. An object-based middleware can be effective to meet these challenges if such a middleware can provide a well-defined development framework as well as lightweight runtime services. In this paper, an adaptive and object-based middleware, called reconfigurable context-sensitive middleware (RCSM) is presented to facilitate context-sensitive communications in ubicomp environments. To facilitates context-sensitive communications, RCSM provides a context-aware interface definition language for specifying context-sensitive interfaces of real-time objects, an object container framework for generating interfaces-specific context-analyzers, and a context-sensitive object request broker for context-sensitive object discovery and impromptu connection management. RCSM is adaptive in the sense that depending on the context-sensitive behavior of the applications, it adapts its object discovery and connection management mechanisms. 相似文献
1000.
Mengmeng Zhang Jiajun Wang Yang Wang Jinfeng Zhang Xiaopeng Han Yanan Chen Yuesheng Wang Zaghib Karim Wenbin Hu Yida Deng 《材料科学技术学报》2021,62(3):119-127
Developing high activity and low-cost materials to produce hydrogen by the sustainable way of photoelectrochemical is key to social development.The abundance and inexpensive Cu2O has been received increasing research as its suitable energy level for photocatalytic water reduction.However,the fast charge recombination rate and the sluggish catalytic kinetics are the huge challenges facing the Cu2O photoreduction.Here,the highly reactive Cu2O@C-MoS2photocathode is constructed by depositing dual-cocatalysts of the carbon layer and MoS2nanosheets on Cu2O nanowires to realize efficient water reduction.An impressive carrier concentration of 6.59×1023cm-3is received,which is 2.78 times of the bare Cu2O,resulting in remarkable enhancement in photocurrent density of 3.34 times for the Cu2O@CMoS2photocathode.Moreover,the applied bias photon-to-current conversion efficiency of the bare Cu2O enhanced 4.5 times from 0.16%to 0.72%in the Cu2O@C-MoS2photocathode.The analysis shows that the Cu2O as light absorber,the carbon layer as electron transfer promoter,and MoS2nanosheets as catalytic sites,thus facilitating chrage separation and enhancing catalytic kinetics.This system paves a feasible strategy for designing other photoelectrodes to realize efficient charge separation and high catalytic activity. 相似文献