Halloysite Nanotubes Modified by Fe3O4 Nanoparticles and Applied as a Natural and Efficient Nanocatalyst for the SymmetricalHantzsch Reaction

Halloysite as an impressive natural eco-friendly nanotube with aluminosilicate structure has been investigated recently due to its unique features such as specific morphology and excellent bio-adaptability. In this research, Fe₃O₄ nanoparticles have been loaded on the tubular halloysite by co-precipitation method in order to synthesis magnetic halloysite (Hal-Fe₃O₄₎. To characterize this recoverable nanocatalyst, applicable analyses such as Fourier-transform infrared (FT-IR) spectroscopy, energy-dispersive X-ray (EDX) analysis, field-emission scanning electron microscopy (FE-SEM) images, X-ray diffraction (XRD) pattern, Thermogravimetric analysis (TGA) and vibrating sample magnetometer (VSM) curves have been carried out. The results confirmed that Fe₃O₄ nanoparticles with cubic structure, and uniform distribution, were located at halloysite nanotubes (HNTs). This aluminosilicate nanocomposite with high thermal stability, crystalline structure, and stable morphology was evaluated as a heterogeneous catalyst in the symmetrical Hantzsch reaction for the first time. Easy synthesis process, green media, high performance, recoverable catalyst and reusing of the Hal-Fe₃O₄ as a nanocatalyst for 8 times are the main features of this protocol.

     

Experimental investigation of solid particles flow in a conical spouted bed using radioactive particle tracking

Solid particles flow in a conical spouted bed is characterized by radioactive particle tracking. The influence of operating conditions on key parameters of this flow is evaluated and discussed: the morphology of the solid bed is not strongly influenced by the forces exerted by the gas on the solid particles, but rather by geometrical considerations; the particles spend approximately 8% of their time in the spout in all experiments; it is the force exerted on the solid particles by the gas that directly controls the volumetric flow rate between adjacent regions, and not the amount of particles in the bed; as U/U_ms increases, the volume of solid particles in the annulus decreases, the volume of solid particles in the fountain increases and the volume of solid particles in the spout remains constant. Correlations to predict key flow parameters as functions of operating conditions are also established and discussed. © 2015 American Institute of Chemical Engineers AIChE J, 62: 26–37, 2016     

Thermal,mechanical, and barrier properties of polyethylene/surlyn/organoclay nanocomposites blown films prepared by different mixing methods

(Low‐density polyethylene) (LDPE)/clay nanocomposites were prepared by melt blending in a twin‐screw extruder by using different mixing methods. Zinc‐neutralized carboxylate ionomer was used as a compatibilizer. Blown films of the nanocomposites were then prepared. The effect of mixing method on the clay dispersion and properties of the nanocomposites was evaluated by wide‐angle X‐ray diffraction analysis, mechanical properties, thermal properties, and barrier properties. The structure and properties of nanocomposites containing different amounts of nanoclay prepared by selected mixing techniques were also investigated. It was found that melt compounding of Surlyn/clay masterbatch with pure LDPE and Surlyn (two‐step‐a method) results in better dispersion and intercalation of the nanofillers than melt mixing of LDPE/Surlyn/clay masterbatch with pure LDPE and surlyn (two‐step‐b method) and direct mixing of LDPE with clay. The films containing ionomer have good barrier properties. A wide‐angle X‐ray diffraction pattern indicates that intercalation of polymer chains into the clay galleries decreases by increasing the clay content. Barrier properties and tensile modulus of the films were improved by increasing the clay content. In addition, tensile strength increased in the machine direction, but it decreased in the transverse direction by increasing the clay content. DSC results showed that increasing the clay content does not show significant change in the melting and crystallization temperatures. The results of thermogravimetric analysis showed that the thermal stability of the nanocomposites decreased by increasing the clay content more than 1 wt%. J. VINYL ADDIT. TECHNOL., 21:60–69, 2015. © 2014 Society of Plastics Engineers     

Optimizing the location of the gas injection well during gas assisted gravity drainage in a fractured carbonate reservoir using artificial intelligence

Gas assisted gravity drainage (GAGD) is a novel subdivision of gas injection method. In this method the injection wells are located in the upper bed of the oil zone, and the production wells are drilled at the bottom bed of the oil zone. Reservoir simulation is among the decision tools for investigating production rate and selecting the best scenarios for developing the oil and gas fields. Selecting the location of the injection wells for reaching the optimized pressure and production rate is one of the most significant challenges during the injection process. Recent experiences have shown that artificial intelligence (AI) is a reliable solution for taking the mentioned decision appropriately and in a least possible time. This study is attributed to the investigation of applying the artificial neural network (ANN) as an artificial intelligence method and a potent predictor for choosing the most proper location for injection in a GAGD process in a fractured carbonate reservoir. The results of this investigation clearly show the efficiency of the ANN as a powerful tool for optimizing the location of the injection wells in a GAGD process. The comparison between the results of ANN and black oil simulator indicated that the predictions obtained from the ANN is highly reliable. In fact the production flow rate and pressure can be obtained in every possible location of the injection well.     

Potential Development of Value-Added Fishery Products in Underutilized and Commercial Fish Species: Comparative Study of Lipid Quality Indicators

In this study, proximate and fatty acid composition in the edible flesh of eight underutilized and five commercial freshwater fish species were compared in order to evaluate the potential of these fish for development of functional value-added fishery products. The lipid content (% dry weight basis) of investigated fish species ranged from 3.44 to 9.25 in underutilized and 3.73–7.68 in commercial species. In comparison with underutilized fish species, commercial species had higher levels of protein (P < 0.05). The high proportion of EPA+DHA was found with Goldfish (524 mg/100 g flesh), Wels (422 mg/100 g flesh), and Crucian carp (354 mg/100 g flesh), all of which belonged to underutilized group. All studied fish (save Lenkoran) showed values higher than the minimum recommended DHA/EPA value (0.45). The ratios of n-6/n-3 found in this study were much lower (save Goatfish) than those cited as a harmful value (4.0 as the maximum value). The PUFA/SFA value of the present fish samples was higher at 1.57 for Goatfish, 1.02 for Lenkoran, 0.68 for Wels, all of these fish belonging to the underutilized group. The highest atherogenic and thrombogenicity index values were generally obtained for commercial species. It seems in respect of comparability of these lipid quality indicators, the underutilized fish species could be highly recommended as an important source of polyunsaturated fatty acids and Max-EPA products for humans consumption.     

BANQ餐厅 美国波士顿

正Banq餐厅位是一家新型餐厅,位于便士储蓄银行(Penny Savings Bank)旧大楼以前用来经营银行业务的大厅内。餐厅分成两个部分,前面区域面向华盛顿大街,设计成酒吧,后面的大厅则作为用餐区。然而,这个空间在z轴上以天花板和地面之间的另一个分区为中心进行设计。如果由于餐厅空间活动的多变性而需要保持灵活性——包括两个座位、四个座位和六个座位,以及与聚会和其他活动有关的座位     

Composite Semiconductor Material of Carbon Nanotubes and Poly[5,5′-bis(3-dodecyl-2-thienyl)-2,2′-bithiophene] for High-Performance Organic Thin-Film Transistors

A nonpercolating network of non-covalently functionalized single-walled carbon nanotubes was embedded within air-stable poly[5,5′-bis(3-dodecyl-2-thienyl)-2,2′-bithiophene] (PQT-12) thin films for the purpose of enhancing the field-effect mobility in thin-film transistors. The host polymer was used to stabilize the nanotubes in suspension through π-orbital overlap caused by simple application of ultrasonication. The stable nanotube suspension was cast into two different device architectures, both of which exhibited excellent on/off ratios ranging from 10⁵ to 10⁶ and dramatically improved mobilities compared with pristine PQT-12 semiconductor. A single-layer film with nanotubes embedded throughout was easy to fabricate and had mobility up to 0.34 cm²/Vs, an enhancement of over 3× compared with PQT-12. Placing the nanotubes closer to the dielectric surface in a dual-layer approach resulted in a mobility improvement of up to six times (0.58 cm²/Vs). The effects of the nanotube content on the polymer interaction within the suspension, film morphology, and electrical properties were investigated as well.     

Modélisation des lignes microrubans supraconductrices couplées déposées sur des substrats diélectriques bianisotropes

In this paper, we model high temperature superconducting coupled microstrip lines printed on bi-anisotropic substrates by the spectral domain Galerkin method. Hence, we have determined the behavior of the effective permittivity for the odd and even modes and the coupling coefficient as a function of several parameters characterizing superconductivity and bi-anisotropy and the geometry of this structure, such as the superconductor material temperature, the distance between the two lines and the optical deviation angles of the dielectric substrates. The validation of the numerical results has been carried out by comparisons with the bibliographic results.