Electronic Contact Deposition onto Organic Molecular Monolayers: Can We Detect Metal Penetration?

Using a semiconductor as the substrate to a molecular organic layer, penetration of metal contacts can be clearly identified by the study of electronic charge transport through the layer. A series of monolayers of saturated hydrocarbon molecules with varying lengths is assembled on Si or GaAs and the junctions resulting after further electronic contact is made by liquid Hg, indirect metal evaporation, and a “ready‐made” metal pad are measured. In contrast to tunneling characteristics, which are ambiguous regarding contact penetration, the semiconductor surface barrier is very sensitive to any direct contact with a metal. With the organic monolayer intact, a metal–insulator–semiconductor (MIS) structure results. If metal penetrated the monolayer, the junction behaves as a metal–semiconductor (MS) structure. By comparing a molecule‐free interface (MS junction) with a molecularly modified one (presumably MIS), possible metal penetration is identified. The major indicators are the semiconductor electronic transport barrier height, extracted from the junction transport characteristics, and the photovoltage. The approach does not require a series of different monolayers and data analysis is quite straightforward, helping to identify non‐invasive ways to make electronic contact to soft matter.     

Printed inductors on alumina substrates

Fabrication of printed inductors on alumina substrate using circular and rectangular shapes of multiturn inductors were studied. The values of the inductors were found to be close to the design values. Inductors with 6 mil spacing were found to be closer to the design values than the 4 and 5 mil of spiral inductors. It may be because of the mutual inductor effect between the turns. Q values of the smaller inductor are comparable to the discrete values. Low-pass filters built using printed inductors between 100 and 400 MHz cut-off frequencies provided close to the simulated performances in which discrete component model were used     

Physicochemical,milling and cooking quality of rice as affected by sowing and transplanting dates

The physicochemical, milling and cooking characteristics of three commercial varieties of paddy viz. Jaya, PR 106 and Pb. Basmati no. 1 as affected by different dates of sowing nursery and transplanting, were investigated. Grain yield was adversely affected with late sowing and transplanting dates. Significant differences were recorded on the yield of head rice and brokens in the three varieties grown under different sowing and transplanting dates. The effect of normal and late dates of sowing on 1000-kernel weight and grain dimensions was significant for both paddy and milled rice. Protein content of rice was not affected by sowing dates but late transplantings resulted in higher values. Free fatty acids in rice and bran were significantly increased with late sowing and transplanting dates, however, the amylose content decreased under these situations. Late transplanting dates decreased the minimum cooking time but increased the solid losses in gruel. The late transplantings deteriorated the organoleptic properties of cooked rice and had higher values for clearing and spreading.     

Mapping of dental science research in India: a scientometric analysis of India’s research output, 1999–2008

The study examines India’s performance based on its publication output in dental sciences during 1999–2008, based on several parameters, including the country annual average growth rate, global publication share & rank among 25 most productive countries of the world, national publication output and impact in terms of average citations per paper, international collaboration output and share and contribution of major collaborative partners, contribution and impact of select top 25 Indian institutions and select top 15 most productive authors, patterns of communication in national and international journals and characteristics of its 45 high cited papers. The study uses 10 years (1999–2008) publications data in dental sciences of India and other countries drawn from Scopus international multidisciplinary bibliographical database.     

Electron multiplying charge-coupled device camera based fluorescence correlation spectroscopy

A fluorescence correlation spectroscopy (FCS) setup is built with an electron multiplying charge-coupled device camera. Although the instrument has a limited time resolution of 4 ms, compared to 0.1-0.2 mus for common instruments using avalanche photodiodes, it allows multiplexing of FCS measurements, has a software-adjustable pinhole after data collection, performs flow speed as well as flow direction measurements in microchannels and could be used to do spectral FCS. Measurements are performed on fluorescent dyes and polystyrene beads in high-viscosity media and on epidermal growth factor receptors in Chinese hamster ovary cells. Using real measurements on single spots, multiplexing of focal spots and detection elements are simulated and the results are discussed.     

Total energy framework, finite elements, and discretization via Hamilton’s law of varying action

Within the total energy framework which we introduce here for the first time (in contrast to Lagrangian or Hamiltonian mechanics framework), we provide an alternative and have developed in this paper a general numerical discretization for continuum-elastodynamics directly stemming from Hamilton’s law of varying action (HLVA) involving a measurable built-in scalar function, namely, Total Energy ${[{\mathcal{E}}\left({{\boldsymbol{q}},\dot{{\boldsymbol{q}}}}\right): TQ\rightarrow {\mathbb{R}}]}$ . The Total Energy we use herein for enabling the space discretization is defined as the kinetic energy plus the potential energy for N-body systems, and the kinetic energy plus the total potential energy for continuum-body systems. It thereby provides a direct measure and sound physical interpretation naturally, while enabling this framework to permit general numerical discretizations such as with finite elements. In the variational formulation proposed here, we place particular emphasis upon the notion that the scalar function which represents the autonomous total energy of the continuum/N-body dynamical systems can be a crucial mathematical function and physical quantity which is a constant of motion in conservative systems. In addition, we prove that the autonomous total energy possesses the three invariant properties and can be viewed as the so-called total energy version of Noether’s theorem; therefore, the autonomous total energy has time/translational/rotational symmetries for the continuum/N-body dynamical systems. The proposed concepts directly emanating from HLVA inherently involving the scalar function, namely, total energy: (i) can be shown to yield the same governing mathematical model equations of motion that are continuous in space and time together with the natural boundary conditions just as Hamilton’s principle (HP) is routinely used to derive such equations, but without obvious inconsistency via such a principle as explained in the paper; (ii) explain naturally the Bubnov–Galerkin weighted-residual form that is customarily employed for discretization for both space and time, and alternately, (iii) circumvent relying on traditional practices of conducting numerical discretizations starting either from the balance of linear momentum (Newton’s second law) involving Cauchy’s equations of motion (governing equations) arising from continuum mechanics or via (i) and (ii) above if one chooses this option, and instead provides new avenues of discretization for continuum-dynamical systems. The present developments naturally embody the weak form in space and time that can be described by a discrete Total Energy Differential Operator (TEDO). Thereby, a novel yet simple, space-discrete Total Energy formulation proposed here only needs to employ the discrete TEDO which provides new avenues and directly yields the semi-discrete ordinary differential equations in time which can be readily shown to preserve the same physical attributes as the continuous systems for continuum-dynamical applications unlike traditional practices. The modeling of complicated structural dynamical systems such as Euler-Bernoulli beams and Reissner–Mindlin plates is particularly shown here for illustration.     

Linking satellite images and hand-held infrared thermography to observed neighborhood climate conditions

While satellite images effectively show surface urban heat islands in urbanized areas, linking surface temperatures to actual ambient temperatures remains a research challenge. Microclimates in urbanized settings can vary tremendously in very short distances, making adequate climate interpolations across a large metropolitan area difficult, at best. This study links the coarse scale of satellite (ASTER) images to the fine scale of hand-held thermography as part of an in-depth suburban neighborhood climate study to determine if ASTER imaging can be used to adequately estimate neighborhood climate conditions in an urbanized area. The study utilizes day and night remotely-sensed and ground data from June, 2004 for Phoenix, Arizona. Microclimate conditions of three urban fringe neighborhoods with varying amounts of natural vegetation and development density were studied, along with ASTER remote sensing data, mobile climate transects, and spot infrared thermographic images.These neighborhoods, though variable, showed only minor differences, and the study indicates that daytime images (11:20 am) do not adequately rank observed conditions within these neighborhoods — the highest ASTER surface temperatures were recorded for the least-dense neighborhood with a natural desert landscaping, though lowest ambient temperatures were measured there. Daytime mean surface temperatures versus air temperatures were 50.4 °C (30.8 °C air temp); 53.5 °C (29.7 °C); and 50.6 °C (31.9 °C). It was found that nighttime (10:40 pm LST) differences among neighborhoods of surface and air temperatures were relatively consistent, with the most densely developed neighborhood having the highest ASTER surface temperatures (29.0 °C) and transect-derived air temperatures (30.0 °C). Issues of view angle, shadowing, emissivity, resolution, and wind conditions for daytime results with their relatively small mean differences observed across the neighborhoods may explain why the rank of ASTER thermal conditions versus observed ambient conditions was poor. However, following sunset, these issues of view angle, etc., are much less problematic.     

Unraveling the droplet drying characteristics of crystallization‐prone mannitol – experiments and modeling

Spray‐dried mannitol is a potential lactose replacement in pharmaceutical formulations, yet the drying behavior of individual mannitol droplets within the spray chamber has not been fully understood. This work explored the drying characteristics of mannitol by employing the reaction engineering approach (REA) in data analysis. A glass filament single droplet drying technique was used to monitor the changes in droplet temperature, mass, and diameter. The drying kinetics data obtained clearly demonstrated the droplet “wet‐bulb” period, the crust formation, and the crystallization phenomena. The master activation‐energy curves developed from REA modeling responded sensitively to varying drying temperatures, which could have led to different crystallization events. The deviation of these plots from the expected norms that do not encounter a phase change was used effectively to discern the physics involved. A REA kinetic model was proposed to assist in process optimization of large‐scale spray‐drying operations. © 2017 American Institute of Chemical Engineers AIChE J, 63: 1839–1852, 2017     

A Theoretical Approach to Evaluating the Performance Characteristics of Double‐Decker High‐Precision Bearings

This paper presents a theoretical approach to evaluating the deflection and indentation of the track surface of the inner race, the stiffness, and the life of double‐decker high‐precision bearings (DDHPBs). The deflection, indentation, and stiffness of DDH‐PBs have been compared with those of conventional bearings of the same bore under identical operating conditions. The analysis, in general, indicates that the deflection of the DDHPB is less and the stiffness is greater than in conventional bearings. Computation of the data under various loads indicates that the indentation on the ball tracks of the DDHPB is comparable to or less than that of conventional bearings of the same bore. The better performance characteristics of the DDHPB make it useful in various industrial applications.