Epoxidized polyurethaneamide and polyesteramide as petroleum pipeline coatings

Linseed oil fatty acids were epoxidized by peracetic acid, then reacted with diethanolamine to give epoxidized hydroxy ethyl linseed oil fatty acid amide ( I ). This amide was rejected with toluene diisocyanate to produce epoxidized polyurethane-amide ( II ). Component I was also reacted with phthalic anhydride to give epoxidized polyesteramide ( III ). Resins II and III were evaluated as coating materials. The results obtained were compared with commercial epoxy resin, and show that resins II and III may be suitable to use as petroleum pipeline coatings.     

Rennet coagulation of buffalo milk as affected by some factors

Thrombelastograph was used to measure the rennet coagulation properties of buffalo milk. The combined effect of pH with temperature fat and protein contents, addition of whey protein concentrat (WPC) and sodium chloride on rennet coagulation (r) and clot forming (K₂₀) times were evaluated. The fat content had little effect on r or K₂₀ compared to pH. Increasing temperature from 30 to 40 °C or the protein content of UF milk retentate from 3 to 12% decreased K₂₀ and K₂₀ of buffalo milk. The K₂₀ was greatly affected by the replacement of casein with 10, 20, 30 and 40% WPC while r was less affected. Addition of sodium chloride (2–10%) increased and K₂₀ and the effect was more pronounced at low pH. The relations between the studied factors and r and K₂₀ of buffalo milk were calculated and discussed.     

A CPW-fed wearable antenna at ISM band for biomedical and WBAN applications

Wireless Networks - In this paper, a Mercedes-Benz logo antenna with a metal plate located at an optimized distance from the proposed antenna is introduced as a wearable antenna to operate in the...     

Fluorimetric Determination of Aluminium using Sequential Injection Analysis (SIA): State of Our Art and Future Developments

Abstract

This paper describes some of our recent advances and proposed future work in the area of fluorimetric determination of Al using sequential injection analysis (SIA). A rapid, automated system was developed with turnover times for sample analysis of <2 min, and attainable limits of detection of <1 ng/mL. The method is cost‐effective and highly competitive. It utilizes three different approaches: (i) molecular imprinted polymers (MIPs); (ii) micellar enhanced treatment; and (iii) renewable surface application. The merits and limitations of each approach are discussed, and the optimum conditions of analysis are presented. The overall sensitivity achieved was more than adequate for general analysis. Proposed new developments involve greater signal enhancement, and improved analytical strategy. The facility is capable of routine application, and is highly beneficial to developing countries in need of cost‐effective techniques for analysis of environmental samples, body fluids, and foodstuffs.     

Prevalence of the Campylobacter multi-drug efflux pump (CmeABC) in Campylobacter spp. Isolated from freshly processed Turkeys

The prevalence of the Campylobacter multi-drug efflux pump (CmeABC) was evaluated in Campylobacter isolates recovered from freshly processed turkeys at two Midwestern processing plants. A total of 94 Campylobacter isolates recovered from processed turkeys were examined using polymerase chain reaction (PCR) to determine the presence of the multi-drug efflux pump genes cmeA, cmeB, and cmeC. Results from this study found that 51% of all isolates tested were positive for CmeABC. 46.6% of these positive isolates were from plant A and 55.1% from plant B. Differences were observed in the prevalence of individual genes found among Campylobacter isolates from each plant. Additional analysis found that among the isolates positive for CmeABC, 85.5% were identified as C. jejuni and 14.5% identified as C. coli. There was a relatively high occurrence of the Campylobacter multi-drug efflux pump genes in Campylobacter spp. recovered from processed turkeys, however, the presence of the genes could not be significantly linked to antimicrobial resistance observed in the test strains and suggests that the CmeABC genes are only one factor associated with antimicrobial resistance in Campylobacter spp.     

Soft and Self-Adhesive Thermal Interface Materials Based on Vertically Aligned,Covalently Bonded Graphene Nanowalls for Efficient Microelectronic Cooling

Urged by the increasing power and packing densities of integrated circuits and electronic devices, efficient dissipation of excess heat from hot spot to heat sink through thermal interface materials (TIMs) is a growing demand to maintain system reliability and performance. In recent years, graphene-based TIMs received considerable interest due to the ultrahigh intrinsic thermal conductivity of graphene. However, the cooling efficiency of such TIMs is still limited by some technical difficulties, such as production-induced defects of graphene, poor alignment of graphene in the matrix, and strong phonon scattering at graphene/graphene or graphene/matrix interfaces. In this study, a 120  µ m-thick freestanding film composed of vertically aligned, covalently bonded graphene nanowalls (GNWs) is grown by mesoplasma chemical vapor deposition. After filling GNWs with silicone, the fabricated adhesive TIMs exhibit a high through-plane thermal conductivity of 20.4 W m⁻¹ K⁻¹ at a low graphene loading of 5.6 wt%. In the TIM performance test, the cooling efficiency of GNW-based TIMs is ≈ 1.5 times higher than that of state-of-the-art commercial TIMs. The TIMs achieve the desired balance between high through-plane thermal conductivity and small bond line thickness, providing superior cooling performance for suppressing the degradation of luminous properties of high-power light-emitting diode chips.     

An energy-saving opportunity in producing lubricating oil using mixed-solventin simulated Rotary Disc Contacting (RDC) extraction tower

Industrial processes are the most energy consuming processes in the world. Modification of these processes helps us with controlling the consumption of energy and minimizing energy loss. Changing raw materials is one of the ways through which we can optimize industrial processes. In this paper, a new solvent mixture (furfural + a co-solvent) was used for the extraction of lubricating base oil from lube-oil cut. It was found that the energy consumption of the new solvent mixture for obtaining a product with the same quality was much lower than the original solvent. By using this new solvent mixture, the operating temperature of the top of tower was reduced by 30 K. This leads to a high reduction in energy consumption in extraction of aromatics from lube oil. At our new extraction process by means of using new solvent mixture, the maximum energy saving was 38% per cubic meter of produced raffinate.     

A thermometric study of the reaction between Fe and HNO3

The reaction between Fe and HNO₃ is studied under a wide variety of conditions by the thermometric technique. Up to 4N HNO₃ ΔT varies linearly with the normality of HNO₃, while in solutions from 6 to 10N HNO₃ it is independent of the concentration. Passivity sets in solutions ≥ 10·8N HNO₃. Calculations of the reaction number (R.N.) reveal that the maximum rate of metal dissolution occurs in 7·3N HNO₃. Fe dissolution in dilute HNO₃ is promoted by additions of NO₃⁻ and NO₂⁻. That the rate-determining step of the autocatalytic process involves HNO₂ is supported by the results of addition of urea to the solution. This additive lowers the maximum measured temperature, without affecting the corresponding time necessary to reach it.Additions of HCI, NaCl, H₂SO₄ and Na₂SO₄ to dilute HNO₃ reduce the dissolution rate of Fe. The effect produced by the salts exceeds that of the acids.In contrast to its action in dilute solutions, the Cl⁻ion induces pitting corrosion in concentrated HNO₃. The attack starts after an induction period which decreases in length as the concentration of HCI is increased. Concentrated HNO₃ can tolerate a certain amount of the aggressive agent before attack starts. The concentration “N_HCl” which can be tolerated depends on that of the passivator according to logN_HCl=a+blog(N−N°)_HNO3 where a and b are constants, and N^o is the least concentration of HNO₃ necessary to cause passivity. Pitting corrosion in concentrated HNO₃ can be initiated also through NaCl. In one and the same acid solution more of NaCl is needed to cause the attack than of HCI.     

The temperature dependence of the fracture toughness and acoustic emission of polycrystalline alumina

The technique of acoustic emission has been shown to be suitable for the monitoring of fracture-toughness tests over a range of temperatures. Commercial polycrystalline alumina has been tested at temperatures up to 1000° C to determine the effect of microstructure and impurity content on fracture toughness and acoustic emission. For a given alumina there was no significant variation in acoustic response or fracture toughness up to 650° C. The emissions observed prior to fracture in this temperature range were attributed to subcritical crack growth. The number of emissions depended on the amount of subcritical crack growth, the grain size, and the presence and amount of porosity. Above 650° C the fracture behaviour changed due to the flow of a grain-boundary glassy phase. This was associated with a peak in the temperature dependence of the apparentK _IC and was accompanied by a large number of acoustic events of low amplitude and low pulse width. At these elevated temperatures the extent of grain-boundary glassy flow, and hence the acoustic response, increased with decreasing grain size and increasing impurity content.