Analysis of VNIR (400–1100 nm) spectral signatures for estimation of soil organic matter in tropical soils of Thailand

The widely available laboratory spectrometers detect targets at spectral regions restricted to visible and near-infrared (VNIR). The spectral response of soils in this region is predominantly featureless and obstructs the exploitation of absorption features as diagnostic criterion. In this study, polynomial based modelling was developed as an alternative method of estimating soil organic matter (OM) from VNIR spectral region. Forty-one core samples, collected from Lop Buri, Thailand, were subjected to chemical and radiometric analysis. Computations were made across four categories of synthesized bandwidths. The selection procedure identified bands at 960, 1100 and 520?nm as OM sensitive. The widening interval of bandwidth has corresponded with diminishing predictive power, termed ‘bandwidth decay effect’. The use of polynomial models and their validations showed a higher performance than the analysis made with multiple regressions analysis. The polynomial based approach offers a fresh opportunity for modelling other non-photoactive soil nutrient parameters. Furthermore, it may form the basis for integration of spectrometers and satellite sensors, aimed at mapping of non-vegetated soils.     

Examination of minimum-heat-flux-point condition for film boiling on a sphere in terms of the limiting liquid superheat and the critical vapor film thickness

Previously proposed theories of the minimum-heat-flux-point (MHF-point) condition were examined using available experimental data obtained from the immersion cooling of spheres in water. The sphere diameter ranged from 9.5 to 30 mm and the liquid subcooling from 0 to 85 K. The limiting liquid superheat predicted by the Lienhard equation was compared with the liquid–solid interface superheat at the instant of liquid–solid contact at the MHF-point. The results showed that the liquid–solid interface superheat was not limited by the limiting liquid superheat and its value was connected with the collapse mode of vapor film. The collapse mode was a coherent collapse at a low interface superheat and the mode changed to a propagative collapse as the interface superheat increased. The critical vapor film thickness obtained from the linear stability analysis of vapor film was compared with the calculated value of average vapor film thickness at the MHF-point. For all data, the ratio of the average vapor film thickness to the critical vapor film thickness was correlated well as a function of liquid subcooling. The ratio decreased with increasing liquid subcooling and tended to about 0.8 to 1 depending on the experiments. This indicated that the MHF-point at a high liquid subcooling was determined by the critical vapor film thickness. A physical consideration was given to the effect of liquid–solid contact that occurred in the film boiling region on the calculated value of the vapor film thickness and the stability of vapor film.     

Flexible LCDs fabricated with a slit coater: Not requiring an alignment film

A homogeneously aligned liquid crystal layer on a substrate film on which it is not necessary to form a liquid crystal alignment film can be assembled by a slit coater. Types of twisted nematic and in‐plane switching flexible liquid crystal displays were demonstrated. The production time can be considerably shortened because of the lack of need for an alignment film. The slit coater method is also applicable to the roll‐to‐roll process.     

A torque-canceling system using the inverse dynamics parallel solution scheme

A new torque-canceling system (TCS) that stabilizes mechanical sway of robots in motions with large inertia by considering the dynamics of the robot itself is discussed in this paper. The TCS cancels the reaction moment generated by the motion of an object by considering the precise dynamics of the object and the body of the robot itself. The dynamics and the reaction moments are calculated using an inverse dynamics parallel solution scheme that handles the dynamics of complex robotic structures by modeling them with finite elements. Once the reaction moment is known, it is canceled by applying an anti-torque to a torque-generating device. The TCS was verified by a simple experimental setup that enables rotational motion around a single axis in the previous paper. However, the effect of the TCS was not confirmed on those cases where mechanical sways are generated not only in the rotational axis of a rotor but also in the orthogonal axis. Therefore, those cases are tested to confirm the function of the TCS in multi-axial cases in this paper. Then, the TCS is mounted on a walking robot with a closed-loop structure and with a walking motion associated with boundary conditions that vary during the motion. The robot sways during its walking motion, and the validity of the TCS is verified by confirming the distances from standard landing point after a multi-step walking sequence.     

Preparation of polybutene‐1/multiwall carbon nanotube composite by oxidation and limonene radical grafting and its characterization

In this study, a novel preparation of a polybutene‐1 (PB) and multiwall carbon nanotube (MWNT) composite was achieved by a combination of PB autooxidation and a radical grafting reaction using an Nd₂O₃/dicumyl peroxide (DCP) radical initiator system with limonene. The autooxidation worked as an amplifier to produce more alkyl radical species in the grafting reaction, and the existence of the MWNTs and the limonene suppressed the side reaction. In addition, the existence of the limonene suppressed the oxidation of the MWNT surface. The composite obtained was assessed in comparison with a PB/MWNT composite and a composite of PB/MWNT modified by Nd₂O₃/DCP without limonene using some spectroscopic methods, optical and electron microscopes, a thermal analyzer and tensile testing. The novel preparation produced a well dispersed nanocomposite compared with the other preparations. The modified MWNT surface was tightly linked to the PB matrix, so that the tensile properties of the composite showed a dependence on MWNT content. Copyright © 2011 Society of Chemical Industry     

Polystyrene photodegradation with a novel titanium dioxide/poly(ethylene oxide)/methyl linoleate paint photocatalyst system

The photodegradation of a polystyrene (PS) film was performed by a titanium dioxide (TiO₂)/poly(ethylene oxide) (PEO)/methyl linoleate (ML) paint photocatalyst system. The PS surface was catalytically photodegraded by the TiO₂/PEO component, and a conjugated carbon–carbon double bond was partially produced. A crosslinking reaction occurred between the PS carbon–carbon double bond and radical spices; as a result, the photodegradation diffusion into the inner region was blocked. The additional ML component certainly blocked the crosslinking reaction and accelerated the photodegradation rate. The fraction of less than 10,000 molecular weight of the 4‐h‐photodegaraded film with the TiO₂/PEO/ML paint was 15.1%, and its photodegradation yield increased four times compared with that with the TiO₂/PEO one. The weight loss values of the photodegraded PS part were 9.9, 10.7, and 11.7% at 4, 8, and 12 h, respectively, and gradually increased with increasing irradiation time. Some part of the film was violently photodegraded by the paint, and its photocatalytic effect lasted. The ML was graft‐polymerized into the film, and a phase separation was caused. The photodegradation behavior between the 0.05‐ and 0.1‐mm films was remarkably different; this showed that the diffusion of the ML radical was affected by the film thickness. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Functional Expression of Thyroid-Stimulating Hormone Receptor on Nano-Sized Bacterial Magnetic Particles in Magnetospirillum magneticum AMB-1

The measurement of autoantibodies to thyroid-stimulating hormone receptor (TSHR) is important for the diagnosis of autoimmune thyroid disease such as Graves’ disease (GD). Although TSHR from porcine thyroid membrane is commonly used for the measurement of TSHR autoantibodies (TRAb), recombinant human TSHR (hTSHR) remains ideal in terms of stable supply and species identity. Here we set out to express recombinant hTSHR on the lipid-bilayer surface of magnetic nanoparticles from a magnetotactic bacterium, Magnetospirillum magneticum AMB-1. Using a tetracycline-inducible expression system, we successfully overexpressed functional hTSHR on bacterial magnetic particles (BacMPs) in AMB-1 via an anchor protein specific for BacMPs. The overexpressed hTSHR was membrane integrated and possessed both ligand and autoantibody binding activity. Our data suggest that hTSHR-displayed BacMPs have potential as novel tools for ligand-receptor interaction analysis or for TRAb immunoassay in GD patients.     

Pure red electroluminescence from novel heteroleptic cyclometalated platinum(II) emitters embedded in polyvinylcarbazole

We fabricated molecularly doped, polymer-based light-emitting diodes possessing a single emitting layer containing a hole-transporting host polymer poly(N-vinylcarbazole) and an electron-transporting auxiliary, 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole, doped with novel phosphorescent cyclometalated Pt(II) complexes bearing arylpyridine and 1,3-diketone ligands. These novel cyclometalated Pt(II) complexes emit pure red color both in steady-state emissions (poly(methyl methacrylate) films)) and electrophosphorescence. They exhibited pure red emissions with the Commission Internationale de l’Eclairage coordinates (X = ～0.67, Y = ～0.33), which is almost identical to the coordinates of standard red (0.66, 0.34) demanded by the National Television System Committee. The color coordinates remained unchanged over a range of operating voltages, even at luminances greater than 1 × 10⁴ cd/m². The maximum external quantum efficiency of these devices exceeded 3.6% and the maximum brightness was greater than 1 × 10⁴ cd/m².     

Characterization and comparison of Asian lacquer saps

Five kinds of Asian lacquer saps, Thailand raw and kurome, China raw and kurome, and Vietnam raw lacquer, were characterized by IR, UV resistance, viscosity, rigid-body pendulum physical property-testing and NMR measurements. The results showed that although Thailand lacquer has the highest oligomer and polymer content, its drying speed is the slowest, and it has the best UV resistance. In addition, the monomer, dimer, trimer, and tetramer fractions of thitsiol of Thailand raw lacquer were separated by HPLC and analyzed by NMR spectroscopy. Almost all proton and carbon NMR peaks were assigned, and the structure of thitsiol was confirmed.