Template synthesis and forming electrical contacts to single Au nanowires by focused ion beam techniques

Metallic Au nanowires were electrochemically synthesized in 20?μm thick ion track etched polycarbonate membranes with the nominal pore diameter of 200?nm. Scanning and transmission electron microscopy analysis and x-ray diffraction of samples revealed that the nanowires are dense with a fcc [Formula: see text] texturing. The I-V characteristics of a single Au nanowire were investigated using a four-point microprobe set-up. The Au nanowire was placed in electrical contact with electrodes patterned on planar substrates using a dual-beam focused ion beam technique. The resistivity of the Au nanowires was found to be 2.8 × 10(-4)?Ω?cm.     

Development and thermal performance of wood-HPDE- PCM nanocapsule floor for passive cooling in building

Cooling demand in the building sector is growing rapidly; thermal energy storage systems using phase change materials (PCM) can be a very useful way to improve the building thermal performance. This work shows the benefits of PCM when incorporated in wood fiber-polymer composite as floor cooling system using nano-encapsulated PCMs. The wood-plastic-NPCM composites were produced using compression molding process and its mechanical and thermal properties were investigated. Two dynamic simulators were employed to investigate synthesized composites thermal performance. Increasing NPCM content in WPC showed that the fluctuations of the simulator temperature was decreased while the heat fluxes through the floor was increased. The variations of ambient maximum temperature have little effect on the air temperature of the simulator with 40% PCM which indicates that the amount of PCM was enough for studied environmental condition. Field experiments were performed using two medium-scale test houses located on Tehran-Iran. It can be concluded that using NPCM helps to reduce heating and cooling demand. Moreover, the natural night ventilation by opening windows reduced the number of hours that the temperature is above 23°C from 499 h/year in case1 (without opening) to 255 h/year in case 2(with opening). This means that natural night ventilation could help reduce the overheating period to about 50% with the use of NPCM.     

The effects of feed bunk competition on the feed sorting behavior of close-up dry cows

The objectives of this research were to describe the feed sorting, feeding behavior, and feed intake of cows consuming a close-up ration and to determine if these behaviors are affected by competition for access to the feed bunk. Thirty-six dry Holstein cows, consuming a close-up total mixed ration diet, were assigned to 1 of 2 treatments: 1) noncompetitive (1 cow/feed bin) or 2) competitive (2 cows/feed bin). Dry matter intake, feeding behavior, and sorting behavior were monitored for each feed bin on 4 separate days during wk 2 and 3 before the anticipated calving dates of the cows. Fresh feed and orts were sampled daily from each bin and were subjected to particle size analysis. The particle size separator consisted of 3 screens (18, 9, and 1.18 mm) and a bottom pan resulting in 4 fractions (long, medium, short, and fine). Sorting was calculated as the actual intake of each particle size fraction expressed as a percentage of the predicted intake of that fraction. Regardless of treatment, the cows sorted against long particles and for short and fine particles. Competition at the feed bunk had no effect on the sorting behavior, dry matter intake, or feeding time of the cows, but did dramatically increase the feeding rate of the cows. The competitively fed cows also had fewer meals per day, and tended to have larger and longer meals. Our results suggest that increased competition at the feed bunk promotes feeding behavior patterns that will likely increase the between-cow variation in composition of total mixed ration consumed.     

Electrodeposition of compositionally modulated Au/Co alloy layers

Au/Co multilayers were electrodeposited from a single bath based on acid citrate, cobalt sulphate and gold cyanide electrolyte. The Taguchi statistical method was used for experiment planning and optimisation. X-ray diffraction (XRD) investigations of the structure showed that the Au deposits exhibited a polycrystalline fcc 1 1 1 structure with an estimated grain size of 7 nm, while the Co deposits exhibited a nano-polycrystalline fcc structure with an estimated grain size ranging between 2 and 28 nm and a strong in-plane texture. The XRD investigation of the multilayer structure also indicated an interface roughness of about 1.5 nm between the Au and Co layers.     

Porous Metal–Organic Framework@Polymer Beads for Iodine Capture and Recovery Using a Gas‐Sparged Column

Iodine (I₂) capture and recovery is an important process in many industrial practices. Conventional materials for I₂ capture include Ag⁰‐based aerogels and zeolites and C‐based aerogels and powders, which suffer from expensive and/or inefficient recovery. Recently, metal–organic frameworks (MOFs) have shown potential as good adsorbents for I₂ capture with high capacity, fast uptake, and good recyclability. The powder form of MOFs, however, often makes them impractical in large‐scale applications. Herein, a versatile method based on the phase inversion technique is presented to fabricate millimeter‐sized spherical MOF@polymer composite beads, and the use of these beads for I₂ capture and recovery is demonstrated. Besides preserving the crystallinity and pore accessibility of the embedded MOFs in the polymeric matrix, the beads exhibit higher capacity and faster uptake rate for I₂ in both vapor and liquid phases compared to the bulk MOF powder. In order to showcase the applicability of these beads, a gas‐sparged column is used as a proof‐of‐concept device that can efficiently capture and recover more than 99% of I₂ from the feeding solution. The beads can be recycled and reused multiple times, which in combination with their easy handling and storage highlights their superiority compared to MOF powders in adsorption applications.     

Liposomes as carrier vehicles for functional compounds in food sector

Liposomes are attractive encapsulation systems that provide enhanced stability of encapsulated materials against a range of environmental, enzymatic, and chemical stresses, including the presence of enzymes or reactive chemicals, and exposure to extreme pH, temperature, and ionic strength changes. Liposomes have been widely used in the pharmaceutical and food industries because of their biocompatibility, biodegradability, absence of toxicity, small size, and ability to carry a wide variety of bioactive compounds due to the amphiphilicity of the phospholipid encapsulating material. In the food industry, liposomes have recently been used to deliver different functional compounds in food systems. In this paper, the food application of liposomes and nanoliposomes as emerging carrier vehicles of vitamins, enzymes, food antimicrobials, essential oils, and polyphenols is discussed in detail.     

A thermal-calorimetric gas flow meter with improved isolating feature

This paper presents design and characterization of a novel thermal-calorimetric flow-meter using suspended-cantilever-structure. There is an air gap between the heater and each individual thermistor providing a good thermal isolation. Due to the suspended-structure which consists of three cantilevers, the thermal convection effect is present on both sides of the active area. Also the velocity boundary layer thickness of the cantilever is much less than closed-membrane one. This characteristic enhances the sensitivity of sensor. The simulation results indicate that the average temperature difference between upstream and downstream thermistors are 36.5 and 1.04 K for flow rate of 1 m/s and the worst case of 0.1 m/s respectively. This solution significantly improves the sensitivity compared to the closed-membrane-structures. The maximum temperature difference causes 94 mV at the output of Wheatstone bridge with 3 V of voltage supply. The calculated and simulated results show that the maximum power consumption of sensor is 4.7 mW at the maximum flow velocity of 1 m/s. The operational range of the designed flow meter is from 0 to 1 m/s. The features of the device are analytically evaluated and simulated under various conditions.

     

Using Copulas for analysis of large datasets in renewable distributed generation: PV and wind power integration in Iran

Renewable distributed generation introduced as an environmental friendly alternative energy supply while it provided the power system with ever-growing technical benefits such as loss reduction and feeder voltage improvement. The evaluation of the effects of small residential photovoltaic and wind DG systems on various system operating indices and the system net load is complicated by both the probabilistic nature of their output and the variety of their spatial allocations. The increasing penetration of renewable distributed generation in power systems necessitates the modeling of this stochastic structure in operation and planning studies. An advanced stochastic modeling of the system requires multivariate uncertainty analysis involving non-normal correlated random variables. Such an analysis is to epitomize the aggregate uncertainty corresponding to spatially spread stochastic variables. In this paper, an integration study of photovoltaics and wind turbines, distributed in a distribution network, is investigated based on the stochastic modeling using Archimedean copulas as a new efficient tool. The basic theory concerning the use of copulas for dependence modeling is presented and focus is given on an Archimedean algorithm. A comprehensive case study for Davarzan area in Iran is presented after reviewing Iran's renewable energy status. This study shows an application of the presented technique when large datasets, assuming 10-min interval between data points of PV, wind and load profiles, are involved where a deterministic study is not trivial.     

Effect of anionic macromolecules on intestinal permeability of furosemide

Context: Furosemide is an anionic molecule and has very low absorption in gastro intestinal tract.

Objective: The aim of this study was to investigate the effect of anionic macromolecules on the intestinal permeability of Furosemide.

Materials and methods: The intestinal permeability of Furosemide was determined using single-pass intestinal perfusion technique in rats. Briefly a jejunal segment of ～10?cm was isolated and cannulated in both ends for inlet and outlet solution. The perfusate was collected every 10 min and samples were analyzed using the RP-HPLC method. Test samples containing furosemide and two anionic macromolecules, sodium carboxy methyl cellulose and sodium alginate, at different concentrations were used.

Results: The obtained data showed that existence of Sodium carboxy methyl cellulose significantly increased the P_eff values in all three investigated concentrations (p?Discussion: It is concluded that the anionic macromolecules at specific concentrations could alter the permeability of anionic drugs across the biological membranes.

Conclusions: Donnan phenomenon and chelating property of macromolecules could be attributed to the observed effect.