New Polymorphs of 2D Indium Selenide with Enhanced Electronic Properties

The 2D semiconductor indium selenide (InSe) has attracted significant interest due its unique electronic band structure, high electron mobility, and wide tunability of its band gap energy achieved by varying the layer thickness. All these features make 2D InSe a potential candidate for advanced electronic and optoelectronic applications. Here, the discovery of new polymorphs of InSe with enhanced electronic properties is reported. Using a global structure search that combines artificial swarm intelligence with first‐principles energetic calculations, polymorphs that consist of a centrosymmetric monolayer belonging to the point group D_3d are identified, distinct from well‐known polymorphs based on the D_3h monolayers that lack inversion symmetry. The new polymorphs are thermodynamically and kinetically stable, and exhibit a wider optical spectral response and larger electron mobilities compared to the known polymorphs. Opportunities to synthesize these newly discovered polymorphs and viable routes to identify them by X‐ray diffraction, Raman spectroscopy, and second harmonic generation experiments are discussed.     

Design and sensitivity analysis of capacitive MEMS pressure sensor for blood pressure measurement

Microsystem Technologies - This paper presents the design and simulation of a MEMS based clamped capacitive pressure sensor for blood pressure measurement. Normally, Blood pressure for human beings...     

Use of Iodine as a Tool to Understand Wheat Starch Pasting Properties

The ability of iodine to bind amylose has been used to understand a variety of structural and functional aspects of starch in food systems. In this study, the changes in starch granule swelling, polymer leaching and their relationship to pasting properties was investigated by adding iodine to the starch slurry at either room temperature or 95°C. The objective of the study was to investigate the contribution of leached and solubilized starch polymers on the pasting behavior of wheat starch. The addition of very small amounts of iodine (0.1%, dry basis, db) at room temperature increased peak and final pasting viscosities as compared to when no iodine was added. Further increases in iodine concentration resulted in a decrease in peak and final pasting viscosities. The amount of iodine required to completely inhibit granule swelling was more than that required to minimize amylose leaching from the granule. Adding increasing amounts of iodine at 95°C to the starch slurry resulted in the gradual decrease in peak and final pasting viscosities. The contrasting effects of iodine on paste viscosity behavior when added at room temperature or at 95°C suggest that the contribution of extra‐granular amylose on the setback viscosity is minimal and a larger proportion of amylose is retained in the intragranular spaces.     

Avalanche Mechanism in p +-n −-n + and p +-n Mid-Wavelength Infrared Hg1−x Cd x Te Diodes on Si Substrates

Hg_1−x Cd _x Te mid-wavelength infrared (MWIR) p ⁺-n ⁻-n ⁺ and p ⁺-n ⁻ avalanche photodiodes (APDs) with a cut-off of 4.9 μm at 80 K were fabricated on Si substrates. Diode characteristics, avalanche characteristics, and excess noise characteristics were measured on two devices. Temperature-dependent diode and avalanche characterization was performed. Maximum 3 × 10⁶ Ω cm² and 9 × 10⁵ Ω cm² zero-bias resistance times active area (R ₀ A) products were measured for the p ⁺-n ⁻-n and p ⁺-n devices at 77 K, respectively. Multiplication gains of 1250 and 410 were measured at −10 and −4 V for the p ⁺-n ⁻-n ⁺ and p ⁺-n APDs at 77 K, respectively, in the front-illumination mode with the help of a laser with an incident wavelength of 632 nm. The gains reduce to 200 and 50 at 120 K, respectively. The excess noise factor in all APDs was measured to be in the range of 1 to 1.2.     

Crystallization kinetic studies of CaBi<Subscript>2</Subscript>B<Subscript>2</Subscript>O<Subscript>7</Subscript> glasses by non-isothermal methods

Transparent glasses of CaBi₂B₂O₇ (CBBO) were fabricated via the conventional melt-quenching technique. The amorphous and the glassy nature of the as-quenched samples were, respectively, confirmed by X-ray powder diffraction (XRD) and differential scanning calorimetry (DSC). The glass transition (T _g) and the crystallization parameters (crystallization activation energy (E _cr) and Avrami exponent (n)) were evaluated under non-isothermal conditions using DSC. The heating rate dependent glass transition and the crystallization temperatures were rationalized by Lasocka equation for the as-quenched CBBO glasses. There was a close agreement between the activation energies for the crystallization process determined by Augis and Bennet and Kissinger methods. The variation of local activation energy (E _c(x)) that was determined by Ozawa method increased with the fraction of crystallization (x). The Avrami exponent (n(x)) decreased with the increase in fraction of crystallization (x), suggesting that there was a changeover in the crystallization process from the bulk to the surface.     

Assessment of Important Sensory Attributes of Millet Based Snacks and Biscuits

There is an increasing push by consumers for new food products that can provide health benefits. To develop these products, sometimes it is necessary to look to alternative crops, 1 of which is millet. For millet to be successfully adopted by consumers, it is necessary to identify and develop product types that are acceptable to North Americans. Biscuits and extruded snacks were produced using varying amounts of refined proso millet flour (0%, 25%, 75%, and 100%). Sensory analysis was conducted on 8 products (4 types of biscuits and 4 types of extruded snack) in 2 separate tests (1 for biscuits and 1 for snacks). Preferred Attribute Elicitation (PAE), a relatively new sensory method, was used to determine attributes affecting liking of the products. Results indicated that as the amount of millet in the biscuits and extruded snacks increased, the liking of the flavor, texture and overall liking decreased. Millet contributed to a bitter taste and bitter aftertaste, and resulted in gritty and dry food products. Further work is required to refine the products tested as well as to identify further products that can be added to the diet in order to take advantage of the health benefits that millet provides.     

The Effect of Stretch Wrap Prestretch on Unitized Load Containment

There are three main factors affecting the stability of a palletized load that is unitized by a stretch wrapping mechanism – the type of unitized load, wrapping configuration and shipping method. The wrapping configuration is typically determined on the basis of the type of unitized load and shipping method. For this study, the aforementioned components were referred to as the package, the product and the distribution environment. This study was designed to observe and understand the interactions between each of the components of the stretch wrap system. Prior to stretch wrapping a pallet of product, the film is elongated or prestretched. The elastic nature of the stretch wrap forces the film to conform to the palletized load. It is hypothesized that the containment force that the stretch wrap applies to the palletized load contributes to improved load containment. Hence, the objective of this study was to determine the existence of a correlation between percentage prestretch to change in containment force and load containment. For the study, a range of prestretched unitized loads were subjected to International Safe Transit Association 3E distribution testing. Simultaneously, the containment force was monitored during the period of distribution testing. Subsequent to distribution testing, the load dispersion was quantified. The data obtained from this test suggested that there is no correlation between percentage prestretch and change in containment force or load containment. Copyright © 2014 John Wiley & Sons, Ltd.     

Measurement and analysis of international air parcel shipping environment for DHL and FedEx between Europe and United States

Various studies have been conducted to determine the dynamics that single packages undergo during distribution between destinations as a function of package size and weight and carrier. Previous studies have normally focused on regional and domestic measurements of these environments in Europe and North America. However, no information is available to determine the international handling and shipping environment of single parcels between the two continents. This study used instrumented packages containing triaxial accelerometers. The measured shocks were analysed to determine the velocity change levels as a function of the events measured in the distribution environment and to develop data for drop heights that can be used for package testing. This study provides a comparison of DHL and FedEx, the two largest international parcel carriers. Copyright © 2007 John Wiley & Sons, Ltd.