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981.
Probiotics in Milk as Functional Food: Characterization and Nutraceutical Properties of Extracted Phenolics and Peptides from Fermented Skimmed Milk Inoculated with Royal Jelly 下载免费PDF全文
982.
M. Khalil Y. F. El-Aryan I. M. Ali 《Journal of Inorganic and Organometallic Polymers and Materials》2016,26(2):359-369
A study on the sorption of Zn2+, Ni2+ and Co2+ onto mixed oxide of Mn and Fe obtained at different hydrothermal conditions and its organic hybrid film modified with polyacrylamide (Mn–Fe oxide/PAM) has been examined. The characterization of inorganic oxides and its composite samples were performed using XRD, SEM, FTIR, XRF and DTA-TGA techniques. The percent sorption of Zn2+, Ni2+ and Co2+ on Mn–Fe oxide at pH 4.5 was 97, 11.85 and 10 % respectively with selectivity order Zn2+ ? Ni2+ > Co2+. The sorption value of Zn2+ at pH 4.5 onto Fe–Mn oxide reached nearly the same value of Zn2+ onto its composite. So, the new compound of Fe–Mn oxide has promising uses for separation of zinc ions while its composite can be used for removal all of these cations. 相似文献
983.
M.I. Khalil O. Van Cleemput A.B. Rosenani C.I. Fauziah J. Shamshuddin 《Nutrient Cycling in Agroecosystems》2003,66(1):13-21
Nitrous oxide (N2O) is formed mainly during nitrification and denitrification. Inherent soil properties strongly influence the magnitude of N2O formation and vary with soil types. A laboratory study was carried out using eight humid tropic soils of Malaysia to monitor NH4
+ and NO3
– dynamics and N2O production. The soils were treated with NH4NO3 (100 mg N kg–1 soil) and incubated for 40 days at 60% water-filled pore space. The NH4
+ accumulation was predominant in the acid soils studied and NO3
– accumulation/disappearance was either small or stable. However, the Munchong soil depicted the highest peak (238 g N2O-N kg–1 soil d–1) at the beginning of the incubation, probably through a physical release. While the Tavy soil showed some NO3
– accumulation at the end of the study with a maximum N2O flux of 206 g N2O-N kg–1 soil d–1, both belong to Oxisols. The other six soils, viz. Rengam, Selangor, Briah, Bungor, Serdang and Malacca series, formed smaller but maximum peaks in an decreasing order of 116 to 36 g N2O-N kg–1 soil d–1. Liming the Oxisols and Ultisols raised the soil pH, resulting in NO3
– accumulation and N2O production to some extent. As such the highest N2O flux of 130.2 and 77.4 g N2O-N kg–1 soil d–1 was detected from the Bungor and Malacca soils, respectively. The Selangor soil, belonging to Inceptisol, did not respond to lime treatment. The respective total N2O formations were 3.63, 1.92 and 1.69 mg N2O-N kg–1 soil from the Bungor, Malacca and Selangor soils, showing an increase by 49 and 99% over the former two non-limed soils. Under non-limed conditions, the indigenous soil properties, viz. Ca++ content, %clay, %sand and pH of the soils collectively could have influenced the total N2O formation. 相似文献
984.
Mohammed Alshareef Khalil Mallah Tyler Vasas Ali Alawieh Davis Borucki Christine Couch Jonathan Cutrone Chelsea Shope Ramin Eskandari Stephen Tomlinson 《International journal of molecular sciences》2022,23(6)
Germinal matrix hemorrhage (GMH) is a devastating disease of infancy that results in intraventricular hemorrhage, post-hemorrhagic hydrocephalus (PHH), periventricular leukomalacia, and neurocognitive deficits. There are no curative treatments and limited surgical options. We developed and characterized a mouse model of GMH based on the injection of collagenase into the subventricular zone of post-natal pups and utilized the model to investigate the role of complement in PHH development. The site-targeted complement inhibitor CR2Crry, which binds deposited C3 complement activation products, localized specifically in the brain following its systemic administration after GMH. Compared to vehicle, CR2Crry treatment reduced PHH and lesion size, which was accompanied by decreased perilesional complement deposition, decreased astrocytosis and microgliosis, and the preservation of dendritic and neuronal density. Complement inhibition also improved survival and weight gain, and it improved motor performance and cognitive outcomes measured in adolescence. The progression to PHH, neuronal loss, and associated behavioral deficits was linked to the microglial phagocytosis of complement opsonized neurons, which was reversed with CR2Crry treatment. Thus, complement plays an important role in the pathological sequelae of GMH, and complement inhibition represents a novel therapeutic approach to reduce the disease progression of a condition for which there is currently no treatment outside of surgical intervention. 相似文献
985.
Muhammad Naeem Amjad Bajes Khalil Zeeshan Tariq Mohamed Mahmoud 《International journal of molecular sciences》2022,23(3)
During the fracture stimulation of oil and gas wells, fracturing fluids are used to create fractures and transport the proppant into the fractured reservoirs. The fracturing fluid viscosity is responsible for proppant suspension, the viscosity can be increased through the incorporation of guar polymer and cross-linkers. After the fracturing operation, the fluid viscosity is decreased by breakers for efficient oil and gas recovery. Different types of enzyme breakers have been engineered and employed to reduce the fracturing fluid′s viscosity, but thermal stability remains the major constraint for the use of enzymes. The latest enzyme engineering approaches such as direct evolution and rational design, have great potential to increase the enzyme breakers’ thermostability against high temperatures of reservoirs. In this review article, we have reviewed recently advanced enzyme molecular engineering technologies and how these strategies could be used to enhance the thermostability of enzyme breakers in the upstream oil and gas industry. 相似文献
986.
Influence of matrix viscosity on the dynamic mechanical performance of magnetorheological elastomers
Nur Haslina Nasirah Abdul Hadi Hanafi Ismail Muhammad Khalil Abdullah Raa Khimi Shuib 《应用聚合物科学杂志》2020,137(13):48492
Anisotropic magnetorheological elastomers (MREs) with different natural rubber matrix viscosities and industrial waste nickel zinc ferrite were prepared in order to assess the dynamic and mechanical performance of the materials. The curing characteristics of the anisotropic MREs were determined using a moving disk rheometer (MDR 2000). The loss tangent (tan δ) was measured through a parallel-plate rheometer over a frequency range of 1─100 Hz (Hz) and a strain amplitude range of 0.1─6%. It was found that tan δ increased with increasing matrix viscosity over the range of frequency and strain amplitude explored. Furthermore, as the matrix viscosity increased, the height of the tan δ peak also increased and the glass transition temperature (Tg) valued shifted to a higher temperature. It was also found that tensile strength and elongation at break increased with increasing matrix viscosity. The SEM micrographs revealed that the columnar structures became longer and thicker with a decrease in matrix viscosity. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48492. 相似文献
987.
Graft polymerization of acrylamide onto rice starch was investigated under different conditions using potassium persulphate, benzoyl peroxide or potassium permanganate as initiator. This has led to establishment of the most appropriate grafting conditions for each of these initiators. Under these conditions grafting was characterized by two rates regardless of the initiator used. The first rate occurred during the initial stages of polymerization while the second during the later stages. The first rates of grafting for the three initiators were very close indicating the insignificant effect of the nature of the initiator on grafting during the initial stages of the reaction. On the other hand, the second rates of grafting exhibited the order: potassium persulphate < benzoyl peroxide < potassium permanganate, reflecting the role played by the nature of initiator during the later stages of the reaction. Substantial differences in solubility were observed between polyacrylamide-starch graft copolymers and unmodified starch as well as among copolymers prepared using the three initiators. Although the copolymers acquired higher solubility percent than the unmodified starch, yet nature of initiator, graft yield, structural changes in the copolymer occuring during grafting and the temperature of solubility measurement determined the solubility percent. Copolymers prepared using benzoyl peroxide or potassium persulphate showed lower viscosity than the unmodified starch. The opposite was the case with respect to copolymer prepared using potassium permanganate. 相似文献
988.
989.
M. A. Abdel Rahim Hanaa B. Hassan M. W. Khalil 《Materialwissenschaft und Werkstofftechnik》1997,28(2):98-102
Inhibition of the corrosion of mild steel in H2SO4 by amino acids was studied by measuring the Tafel polarization curves. Nineteen different naturally occuring amino acids were used as corrosion inhibitors. Two-site adsorption model was proposed to explain the adsorption of some amino acids on the metal surface. At 1 × 10?4M concentration of inhibitor, the best corrosion inhibition was obtained with the sulphur-containing amino acids. Other amino acids gave various corrosion inhibition efficiency depending or their structure. 相似文献
990.
Mohammed M’Hamdi Asbjørn Mo Christophe L. Martin 《Metallurgical and Materials Transactions A》2002,33(7):2081-2093
The two-phase mass and momentum conservation equations governing shrinkage-driven melt flow and thermally induced deformation
are formulated for the aluminum direct chill (DC) casting process. Two main mechanisms associated with hot tearing formation
during solidification and subsequent cooling are thus addressed simultaneously in the same mathematical model. The approach
unifies the two-phase mushy zone model outlined by Farup and Mo, the constitutive relations that treat the mushy zone as a
viscoplastic porous medium saturated with liquid outlined by Martin et al., and the “classical” mechanics approach to thermally induced deformations in solid (one-phase) materials using the linear
kinematics approximation. A temperature field and a unique solidification path are considered as input to the model. The governing
equations are solved for a one-dimensional (1-D) situation with some relevance to the DC casting process. The importance of
taking into account the transfer of momentum from the liquid phase to the solid phase is then demonstrated through modeling
examples. Furthermore, the modeling results indicate that the constitutive law governing the viscoplastic behavior of the
solid skeleton of the mushy zone should take into account that the solid skeleton can be compressed/dilated as well as stress
space anisotropy. Calculated peak values for liquid pressure and solid stress turn out to correlate to the hot tearing susceptibility
measured in casting trials in the sense that trials having the largest cracks are those for which the highest pressures and
stresses are computed. 相似文献