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Muhammad Asif Khan Muhammad Nadeem Allah Rakha Sadaf Shakoor Aamir Shehzad Moazzam Rafiq Khan 《International Journal of Food Properties》2016,19(4):929-935
Cereal mixed linkages (1 → 3) (1 → 4)-β-D-glucan is a linear polysaccharide composed of glucose units. Oat β-glucan is a natural polymer. The main products of β-glucanase are oligosaccharides with DP3 and DP4, i.e., 3-Ob-cellobiosyl-D-glucose and 3-Ob-cellotriosyl-D-glucose, which represent over 90% of the molecule. Keeping in mind all the benefits of oat bran, the present study was planned to investigate the structural properties of oat bran, high-performance anion exchange chromatography with pulsed amperometric detection was used to examine these oligosaccharides. The structural analysis of oat bran of two oat varieties revealed that the ratio of soluble and insoluble triose to tetraose in β-glucan fraction was 1.44 and 1.78, respectively, for Avon variety; while the ratio of soluble and insoluble triose to tetraose in β-glucan fraction for Sargodha-81 was 1.49 and 1.77. The major units determined were cellotriose and cellotetraose. Other units cellopentaose and hexaoses were also existed but in minor fractions. Lichenase hydrolysis high-performance anion exchange chromatography with pulsed amperometric detection appeared to be the best choice for structural analysis of purified samples of mixed-linkage β-glucan. 相似文献
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Synthesis of Sulfur‐Based Biocompatible Nonionic Surfactants and Their Nano‐Vesicle Drug Delivery 下载免费PDF全文
Imdad Ali Muhammad Raza Shah Muhammad Imran Shafiullah 《Journal of surfactants and detergents》2017,20(6):1367-1375
Nonionic surfactants are capable of forming nano‐range vesicles upon self‐assembling in an aqueous medium. These vesicles are highly stable, low in toxicity, and cost‐effective. Owing to their ability to solubilize both hydrophilic and hydrophobic substances, they are of great interest for drug solubilization and delivery. This study describes the synthesis and characterization of two new nonionic surfactants and their screening for biocompatibility and drug loading potentials in nano‐scale niosomal vesicles. They were characterized through mass spectroscopy, 1HNMR, and FT‐IR. Their critical micelle concentration (CMC) was investigated using UV–vis spectrophotometry. The biocompatibility study was carried out through blood hemolysis and in vitro cytotoxicity assays. The surfactants have very low CMC values, are highly hemo‐compatible, and were nontoxic when tested against a cell culture. They were able to form nano‐range niosomal vesicles with large variation in their size. Both new surfactants were able to encapsulate increased amounts of the drug, in this case clarithromycin. The chemical nature of the drug remained intact in the niosomal vesicles. The results suggest that these nonionic surfactants could be promising drug delivery vehicles. 相似文献
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Sami Ullah Faiz Ahmad Abdullah G. Al-Sehemi Mohammed Ali Assiri Muhammad Rafi Raza Ahmad Irfan 《应用聚合物科学杂志》2021,138(17):50310
This research aims to study the effect of ammonium polyphosphate and expandable graphite on the intumescent coating formulations (ICF). The coating presented in this research article is based on carbon source expandable graphite (EG), blowing agent melamine, acid source ammonium polyphosphate (APP), epoxy resin as a binder with polyamide amine. The stability of the developed coating was verified at 950°C for 1-hour fire test. The results showed that the coating is stable and well bond with the steel substrate. The char was characterized by using FESEM, XRD, FTIR, DTA, TGA, XPS, Py-GCMS and Weathering Test. The morphology of the char was studied by SEM of the coating after furnace fire test. XRD and FTIR show the presence of graphite, borophosphate; boron oxide and sassolite in the residual char. TGA and DTG disclosed that EG improved the residual mass of coating. XPS analysis showed the char residue of IF5-APP-EG contains carbon and oxygen contents 47.50 and 40.70, respectively. Py-GCMS analysis described that the IF5-APP-EG released less gaseous compounds. The weathering test illustrated that's the char expansion of coatings samples was decreased due to the presence of a humid environment and UV light. The IF5-APP-EG showed the maximum char expansion, lower substrate temperature and high residual weight among the studied formulations. 相似文献
37.
Ying Ma Xiaodi Wang Rizwan Raza Mamoun Muhammed Bin Zhu 《International Journal of Hydrogen Energy》2010
The novel core–shell nanostructured SDC/Na2CO3 composite has been demonstrated as a promising electrolyte material for low-temperature SOFCs. However, as a nanostructured material, stability might be doubted under elevated temperature due to their high surface energy. So in order to study the thermal stability of SDC/Na2CO3 nanocomposite, XRD, BET, SEM and TGA characterizations were carried on after annealing samples at various temperatures. Crystallite sizes, BET surface areas, and SEM results indicated that the SDC/Na2CO3 nanocomposite possesses better thermal stability on nanostructure than pure SDC till 700 °C. TGA analysis verified that Na2CO3 phase exists steadily in the SDC/Na2CO3 composite. The performance and durability of SOFCs based on SDC/Na2CO3 electrolyte were also investigated. The cell delivered a maximum power density of 0.78 W cm−2 at 550 °C and a steady output of about 0.62 W cm−2 over 12 h operation. The high performances together with notable thermal stability make the SDC/Na2CO3 nanocomposite as a potential electrolyte material for long-term SOFCs that operate at 500–600 °C. 相似文献
38.
Naveed Abbas Tanzila Saba Amjad Rehman Zahid Mehmood Nadeem Javaid Muhammad Tahir Naseer Ullah Khan Khawaja Tehseen Ahmed Roaider Shah 《Microscopy research and technique》2019,82(7):1198-1214
Malaria is a serious worldwide disease, caused by a bite of a female Anopheles mosquito. The parasite transferred into complex life round in which it is grown and reproduces into the human body. The detection and recognition of Plasmodium species are possible and efficient through a process called staining (Giemsa). The staining process slightly colorizes the red blood cells (RBCs) but highlights Plasmodium parasites, white blood cells and artifacts. Giemsa stains nuclei, chromatin in blue tone and RBCs in pink color. It has been reported in numerous studies that manual microscopy is not a trustworthy screening technique when performed by nonexperts. Malaria parasites host in RBCs when it enters the bloodstream. This paper presents segmentation of Plasmodium parasite from the thin blood smear points on region growing and dynamic convolution based filtering algorithm. After segmentation, malaria parasite classified into four Plasmodium species: Plasmodium falciparum, Plasmodium ovale, Plasmodium vivax, and Plasmodium malaria. The random forest and K‐nearest neighbor are used for classification base on local binary pattern and hue saturation value features. The sensitivity for malaria parasitemia (MP) is 96.75% on training and testing of the proposed approach while specificity is 94.59%. Beside these, the comparisons of the two features are added to the proposed work for classification having sensitivity is 83.60% while having specificity is 94.90% through random forest classifier based on local binary pattern feature. 相似文献
39.
Danish Mahmood Nadeem Javaid Imran Ahmed Nabil Alrajeh Iftikhar Azim Niaz Zahoor Ali Khan 《国际能源研究杂志》2017,41(14):2074-2090
In this paper, a multi‐agent‐based locally administrated power distribution hub (PDH) for social welfare is proposed that optimizes energy consumption, allocation, and management of battery energy storage systems (ESSs) for a smart community. Initially, formulation regarding optimum selection of a power storage system for a home (in terms of storage capacity) is presented. Afterwards, the concept of sharing economy is inducted in the community by demonstrating PDH. PDH is composed of multiple small‐scale battery ESSs (each owned by community users), which are connected together to form a unified‐ESS. Proposed PDH offers a localized switching mechanism that takes decision of whether to buy electricity from utility or use unified‐ESS. This decision is based on the price of electricity at ‘time of use’ and ‘state of charge’ of unified‐ESS. In response to power use or share, electricity bills are created for individual smart homes by incrementing or decrementing respective submeters. There is no buying or selling of power from PDH; there is power sharing with the concept of ‘no profit, no loss’. The objective of the proposed PDH is to limit the purchase of electricity on ‘high priced’ hours from the utility. This not only benefits the utility at crucial hours but also provides effective use of power at the demand side. The proposed multi‐agent system depicts the concept of sharing power economy within a community. Finally, the proposed model is analyzed analytically, considering on‐peak, off‐peak, and mid‐level (mid‐peak) prices of a real‐time price signal during 24 h of a day. Results clearly show vital financial benefits of ‘sharing power economy’ for end users and efficient use of power within the smart community. Copyright © 2017 John Wiley & Sons, Ltd. 相似文献
40.
Single-phase NiFe2O4 nanoparticles embedded in SiO2 matrix have been synthesized by sol-gel method. Average particle size lies in the range 8?C12 nm. Magnetic measurements are taken by SQUID-magnetometer with a maximum applied field of ??7 T and temperature down to 4.2 K. An exchange bias effect in nanoparticles is due to the existence of strong core-shell interactions and it vanishes as the particle size decreases (<4?nm). Spin disorder and frustration appear at the core-shell interface due to broken bonds on the surface. We have observed the exchange bias effect via hysteresis loop shift, when the sample is cooled in an applied field of 5?T. In both AC and DC fields, our system exhibit memory effects at the halted temperatures. Furthermore, a sharp increase of coercivity at low temperatures (<50 K) is observed, which is attributed to increased surface anisotropy at low temperatures. For saturation magnetization vs. temperature data, Bloch??s T 3/2 law (M(T)=M(0)?(1?BT b )) is fitted well and yields: B=4??10?05 K?3/2 and b=1.53. All these measurements prove the presence of exchange bias (core-shell interactions), memory effects, validation of Bloch??s T 3/2 law and freezing effects in nickel ferrite nanoparticles dispersed in SiO2 matrix. 相似文献