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951.
952.
Absorbency testing is used to determine the percentage of ZnCl2 or NH4Cl solution absorbed by a hydroponics gel (HPG). It is found that the absorbency of ZnCl2 or NH4Cl solution decreases with increasing solution concentration. The conductivity of ZnCl2- and NH4Cl-HPG electrolytes is dependent on the solution concentration. A mixture of salt solution with HPG yields excellent gel polymer electrolytes with conductivities of 0.026 and 0.104 S cm−1 at 3 M ZnCl2 and 7 M NH4Cl, respectively. These gel electrolytes are then used to produce zinc–carbon cells. The fabricated cells give capacities of 8.8 and 10.0 mAh, have an internal resistance of 25.4 and 19.8 Ω, a maximum power density of 12.7 and 12.2 mW cm−2, and a short-circuit current density of 29.1 and 33.9 mA cm−2 for ZnCl2- and NH4Cl-HPG electrolytes, respectively. 相似文献
953.
In this research, the influence of warm mix additives on the properties of warm-mix asphalt (WMA) containing recycled asphalt pavement (RAP) was investigated and compared with the same graded hot-mix asphalt (HMA). WMA mixtures were produced using Sasobit and Zycotherm as organic and chemical WMA additives, respectively. Mixtures were prepared containing RAP in different proportions (0%, 25%, 50% and 75 % of total aggregates). Dynamic creep and wheel track tests were used to investigate the resistance of specimens to permanent deformation. Zycothem WMA mixtures showed less resilient modulus and rutting resistance than Sasobit WMA mixtures. It was also concluded that increasing the amount of RAP in mixtures improves resilient modulus and rutting resistance of all mixtures. 相似文献
954.
Lida Rafati Ramin Nabizadeh Amir Hossein Mahvi Mohamad Hadi Dehghani 《Korean Journal of Chemical Engineering》2012,29(4):473-477
Lewatit FO36 resin was covered with Fe (III) nano-particles, and it was used as a new way to eliminate phosphate. Column experiments
were carried out in 11 stages in fixed bed columns with constant flow rate of 9 ml/min and the empty bed contact time (EBCT)
of 2.1 min. The adsorption capacity was calculated for different concentration of phosphate solutions. After resin was regenerated
by using NaOH and NaCl solutions, the adsorption capacity of resin was computed for 6mg/L of phosphate, typically. The adsorption
capacity of resin was checked again a typical concentration of phosphate. The adsorption capacity measurements of regenerated
resin show that the concentration of phosphate reached to 1.6mg/g after an 8.5% decrease when the initial concentration of
phosphate is 6 mg/L. Competition of anions with phosphate was analyzed using chloride, sulfate, bicarbonate and a combination
of these anions. Finally the effect of resin in phosphate removal was studied for a typical real sample, and the data was
analyzed using statistical software (SPSS 13). The statistical results indicated that Cl−, SO43−, HCO3− and combined competing anions did not have a strong influence on the phosphate removal efficiency. 相似文献
955.
Yien Yien Ong Wen Siang Tan Mohamad Rosfarizan Eng Seng Chan Beng Ti Tey 《Journal of food science》2012,77(10):M560-M564
Abstract: Red dragon fruit or red pitaya is rich in potassium, fiber, and antioxidants. Its nutritional properties and unique flesh color have made it an attractive raw material of various types of food products and beverages including fermented beverages or enzyme drinks. In this study, phenotypic and genotypic methods were used to confirm the identity of lactic acid bacteria (LAB) appeared in fermented red dragon fruit (Hylocereus polyrhizus) beverages. A total of 21 isolates of LAB were isolated and characterized. They belonged to the genus of Enterococcus based on their biochemical characteristics. The isolates can be clustered into two groups by using the randomly amplified polymorphic DNA method. Nucleotide sequencing and restriction fragment length polymorphism of the 16S rRNA region suggested that they were either Enterococcus faecalis or Enterococcus durans. Practical Application: Current research revealed the use of biochemical analyses and molecular approaches to identify the microbial population particularly lactic acid bacteria from fermented red dragon fruit juices. 相似文献
956.
Thermophilic Campylobacter spp. in salad vegetables in Malaysia 总被引:1,自引:0,他引:1
Chai LC Robin T Ragavan UM Gunsalam JW Bakar FA Ghazali FM Radu S Kumar MP 《International journal of food microbiology》2007,117(1):106-111
The main aim of this study was to combine the techniques of most probable number (MPN) and polymerase chain reaction (PCR) for quantifying the prevalence and numbers of Campylobacter spp. in ulam, a popular Malaysian salad dish, from a traditional wet market and two modern supermarkets in Selangor, Malaysia. A total of 309 samples of raw vegetables which are used in ulam were examined in the study. The prevalences of campylobacters in raw vegetables were, for supermarket I, Campylobacter spp., 51.9%; Campylobacter jejuni, 40.7%; and Campylobacter coli, 35.2%: for supermarket II, Campylobacter spp., 67.7%; C. jejuni, 67.7%; and C. coli, 65.7%: and for the wet market, Campylobacter spp., 29.4%; C. jejuni, 25.5%; and C. coli, 22.6%. In addition Campylobacter fetus was detected in 1.9% of raw vegetables from supermarket I. The maximum numbers of Campylobacter spp. in raw vegetables from supermarkets and the wet market were >2400 and 460 MPN/g, respectively. 相似文献
957.
Nor Anizah Mohd Nor Siti Balkis Budin Satirah Zainalabidin Juriyati Jalil Syaifuzah Sapian Fatin Farhana Jubaidi Nur Najmi Mohamad Anuar 《International journal of molecular sciences》2022,23(12)
Diabetes-induced vascular disorder is considered one of the deadly risk factors among diabetic patients that are caused by persistent hyperglycemia that eventually leads to cardiovascular diseases. Elevated reactive oxygen species (ROS) due to high blood glucose levels activate signaling pathways such as AGE/RAGE, PKC, polyol, and hexosamine pathways. The activated signaling pathway triggers oxidative stress, inflammation, and apoptosis which later lead to vascular dysfunction induced by diabetes. Polyphenol is a bioactive compound that can be found abundantly in plants such as vegetables, fruits, whole grains, and nuts. This compound exerts therapeutic effects in alleviating diabetes-induced vascular disorder, mainly due to its potential as an anti-oxidative, anti-inflammatory, and anti-apoptotic agent. In this review, we sought to summarize the recent discovery of polyphenol treatments in modulating associated genes involved in the progression of diabetes-induced vascular disorder. 相似文献
958.
A.A. Mohamad M. El-Ganaoui R. Bennacer 《International Journal of Thermal Sciences》2009,48(10):1870-1875
Natural convection in an open ended cavity is simulated using Lattice Boltzmann Method (LBM). The paper is intended to address the physics of flow and heat transfer in open end cavities and close end slots. The flow is induced into the cavity by buoyancy force due to a heated vertical wall. Also, the paper demonstrated that open boundary conditions used at the opening of the cavity is reliable, where the predicted results are similar to conventional CFD method (finite volume method, FVM) predictions. Prandtl number (Pr) is fixed to 0.71 (air) while Rayleigh number (Ra) and aspect ratio (A) of the cavity are changed in the range of 104–106 and of 0.5–10, respectively. It is found that the rate of heat transfer deceases asymptotically as the aspect ratio increases and may reach conduction limit for large aspect ratio. The flow evaluation in the cavity starts with recirculation inside the cavity, as the time proceeds the flow inside the cavity communicates with the ambient. 相似文献
959.
Water is a very crucial natural resource in the world and because of its selective availability among different countries;
it will be the most precious commodity in the future. In the Mediterranean basin one can find a mosaic of countries rich in
water and others poor. However, the common issue for all these countries is how to improve water resources management. NOSTRUM-DSS
[Network on Governance, Science and Technology for Sustainable Water Resources Management in the Mediterranean. The role of
DSS (Decision Support System) tools. Contract 509158. August 2004–August 2007], which is a co-ordination action funded by
the European Commission under the Sixth Framework Program, aims to contribute to the achievement of improved governance and
planning in the field of sustainable water management. In order to achieve this goal, DSS tools which can ease the problem
of accessing information about an Integrated Water Resource Management (IWRM) for decision makers, scientific community, and
other organizations must be created. An online database is one of these tools which can help in creating an IWRM. This tool
can reduce information redundancy, eliminate unneeded expenses, and create regional cooperation in the area of water resources
management. In this paper a new Web based meta-database about climate, remote sensing, and Geographic Information System (GIS)
related to water resources management is introduced, and its role in improving water resources management is discussed. 相似文献
960.
Epoxy micro-balloons are prepared by dropping and stirring of epoxy mixture in heated silicon oil. The mixture of epoxy, curing agent and blowing agent forms sphere particles, which are then blown via the function of blowing agent and simultaneously cured to form epoxy micro-balloons. Different ratio of epoxy and hardener will produce different types of epoxy micro-balloons. Schematic illustrations to produce the epoxy micro balloons are also proposed. 相似文献