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Inclined multi-hole full-coverage film cooling, as a practical cooling scheme, has received widespread application in combustion chambers. In the initial stage of combustion chamber design, the numerical simulation of three-dimensional structure is a long calculation period. A simple one-dimensional program can shorten the design cycle, which is used to preliminaries calculate heat transfer characteristics and flow distribution. A simple temperature calculating method of inclined multi-hole wall temperature in the high temperature combustor flame tube was developed. The flow and heat transfer characteristics in the combustor can be expected by this method. Heat transfer in the combustor flame tube is researched based on the plate flow field. The coupling effects of heat transfer, wall heat conduction and radiation heat transfer are considered, such as convective and Radiative heat transfer between primary flame flow and the hot wall side, convective heat transfer in the film holes, convection and radiative heat transfer between the cool wall side and the annular cooling air flow, radial heat conduction inside the wall. In the initial stage of combustion chamber with inclined multi-hole design, the design cycle can be shortened by this method, using relatively simple calculation to know the combustion chamber wall temperature. Keywords: Combustion chamber, Inclined multi-hole, Film cooling, Wall temperature, Flame tube

Abstract Visible transparent UV protective coatings were developed by incorporating nano-Ti[O.sub.2] into waterborne acrylic systems to provide UV protection for UV-sensitive color cool roofing. Water-based high crystalline Ti[O.sub.2] nanoparticle suspension [...]

Irregular hemorrhagic traumas always threaten the health of patients due to uncontrollable bleeding and wound infections. The traditional hemostatic materials show dissatisfactory hemostatic efficiency and antibacterial activity in solving these potential bleeding dangers. Herein, we proposed a kind of composites based on flexible wood membrane (FWM) loaded with chitosan/alginate derivative for accelerating rapid hemostasis and preventing infection. FWM was removed part of hemicellulose and lignin by using NaOH/Na 2 SO 3 mixture to obtain excellent flexibility while retaining the original porous structure, followed by loading silver nanoparticles on the FWM surface to prepare AgNPs-FWM as an antibacterial bio-carrier. Then, AgNPs-FWM was coated with polyoxyethylene stearate-modified chitosan and multi-aldehyde sodium alginate to fabricate the composites of chitosan/alginate/AgNPs-FWM (CSA/AgNPs-FWM) using in-situ Schiff base reaction. Furthermore, in vitro and in vivo experiments showed that the CSA/AgNPs-FWM composites exhibited lower BCI value (2.6 ± 1.3 %), more rapid hemostasis (26 s) and lower blood loss (67.8 mg) than that of the traditional materials. The possible mechanism for the hemostasis process was not only the high blood absorption capacity, but also the synergistic interaction between hydrophobic alkane chains, amino groups, aldehydes, hydroxyl groups and blood cells. Moreover, CSA/AgNPs-FWM showed exceptional superiorities in mechanical properties and antibacterial activity, which endowed composites high potential in hemostasis application for irregular external wound. • FWM with native porously microstructure and flexibility was designed as a green and safe biocarrier. • CSA/AgNPs-FWM could aggregate and stimulate blood cells/platelets, promoting blood coagulation. • CSA/AgNPs-FWM could achieve shape adaptation to the surrounding tissues and the wound cavities to protect injured tissue. • CSA/AgNPs-FWM exhibits rapid hemostasis and long-term antibacterial properties. [ABSTRACT FROM AUTHOR]

A state-of-the-art gas sensor is developed to measure extremely small concentrations of a chemical vapor in the air in a range lower than 0.1 parts per billion. The sensor enables simultaneous measurement of a chemical (methyl salicylate) with a resonant electromagnetic structure and radiating the information back to a base station. The chemical sensor is composed of a layer of graphene (transduction layer) with a molecular imprinting polymer (MIP) layer (sensor) on top. This leads to a combination of the ultra high sensitivity of graphene with the exquisite selectivity of the molecular imprinting technique (MIT). The sensor is electrically embedded within a patch antenna. The simulation results using Ansoft high-frequency structure simulator (HFSS) are presented along with test data that show parts per trillion (ppt) detection levels. [ABSTRACT FROM AUTHOR]

A developed effective chiral Lagrangian approach is used to study the cold dense nuclear matter. Improved calculation of baryon number density as a function of chemical potential is given. The resonance appeared in a natural way as chemical potential is getting larger. Calculations of susceptibility and pressure including the resonance contribution are also given. [ABSTRACT FROM AUTHOR]

In this paper, magnetic field and equation of state (EoS) of neutron star matter are studied under relativistic mean field theory. A nonzero mass term of magnetic field in the Lagrangian is introduced, which depends on baryon density of charged particles. The magnetic field has not been treated as external as usual and the calculations of magnetic field strength at finite temperature reveal the existence of inflection points in certain densities. [ABSTRACT FROM AUTHOR]

Assembly of nanowires into ordered macroscopic structures has attracted great scientific interest in the past decade. In this work, we report on a rapid low-cost scalable oil–water (two-phase) interfacial self-assembly process for fabricating aligned Ag nanowire (AgNW) films on solid substrates. This process is much simpler than traditional Langmuir–Blodgett (LB) techniques and allows the assembly of one-dimensional Ag nanowires on any solid substrate without extra pretreatment of either the surface of silver nanowires or the solid substrate. The resultant aligned AgNW films can be used as robust surface-enhanced Raman scattering (SERS) substrates for chemical and biomolecular detection with highly uniform and repeatable SERS signals over the entire substrate. Sensitive and quantitative detection of the toxicant arsenic in drinking water using these AgNW films are subsequently presented to demonstrate potential applications for environmental pollutant analysis. [ABSTRACT FROM AUTHOR]

Arsenic (As) is one of the most toxic contaminants found in the environment. Development of novel detection methods for As species in water with the potential for field use has been an urgent need in recent years. In past decades, surface-enhanced Raman scattering (SERS) has gained a reputation as one of the most sensitive spectroscopic methods for chemical and biomolecular sensing. The SERS technique has emerged as an extremely promising solution for in-situ detection of arsenic species in the field, particularly when coupled with portable/handheld Raman spectrometers. In this article, the recent advances in SERS analysis of arsenic species in water media are reviewed, and the potential of this technique for fast screening and field testing of arsenic-contaminated environmental water samples is discussed. The problems that remain in the field are also discussed and an outlook for the future is featured at the end of the article. [ABSTRACT FROM AUTHOR]

Surface-enhanced Raman scattering (SERS) has emerged as one of the most sensitive spectroscopic analysis methods for the detection of environmental contaminants in water, including perchlorate (ClO4(-)). However, as with other commonly used analytical techniques, analysis of realistic environmental samples by SERS presents a challenge due to complex chemical components coexisting in the samples. In this work, we investigated the influence of inorganic anions (particularly oxyanions) on SERS spectra of ClO4(-) using a cationic thiol modified silver nanofilm substrate (Cys-Ag/rCu). The results show that the anions present in the samples did not shift the ClO4(-) characteristic band positions, but did decrease signal intensities due to their competitive binding with the -NH3(+) groups of cationic thiol molecules immobilized on the substrates. The pH changes caused by both the dissociation of H2PO4(-) and the hydrolysis of HCO3(-) may also play a non-negligible role. The selectivity of the Cys-Ag/rCu substrate towards these anions was determined to be in the following order: ClO4(-)>SO4(2-)>HCO3(-), NO3(-)>Cl(-)>H2PO4(-), indicating preferential adsorption of ClO4(-) ions. In the solutions with multiple anions present, the ClO4(-) SERS spectra were affected simultaneously by all the coexisting anions. Calibration curves with very good linear relationships were successfully obtained, demonstrating the great potential of quantitative detection of aqueous ClO4(-) in the matrix., (Copyright © 2014 Elsevier B.V. All rights reserved.)