Recent advances in automobile exhaust catalyst

Catalysts that were recently developed by Toyota for the control of automobile exhaust are reviewed. (1) A system combining a close-coupled catalyst with high heat resistance and an under-floor catalyst with high oxygen storage capacity were developed for low emission vehicles. (2) Based on a new concept, a three-way catalyst having the ability to store NOx at oxidizing atmosphere and to reduce stored NOx at stoichiometric or reducing atmosphere was developed for automotive lean burn engines. (3) A thin wall ceramic substrate was developed for better catalyst performance.     

Thermodynamic analysis of fly ash nanofluid for automobile (heavy vehicle) radiators

Journal of Thermal Analysis and Calorimetry - On the basis of symmetry group analysis applied to fluid flow, heat and mass transfer equations for nanofluids in parabolic approximation, their...     

A review on fuel cell types and the application of nanofluid in their cooling

Journal of Thermal Analysis and Calorimetry - The application of nanofluid in cooling systems is increasing. The nanofluid consists of a mixture of nanometallic and nonmetallic particles, which...     

Effect of nanoparticles concentration on the characteristics of nanofluid sprays for cooling applications

Journal of Thermal Analysis and Calorimetry - This study addresses the effect of nanofluid synthesis on the rheological properties of the resulting fluid and their consequent effect on the...     

Similarity solution of air and nanofluid impingement cooling of a cylindrical porous heat sink

Journal of Thermal Analysis and Calorimetry - In the present paper, a numerical study on flow and heat transfer of air/nanofluid impinging jet flow through a cylindrical porous heat sink has been...     

Recent lean NOx catalyst technologies for automobile exhaust control

The current status of our development work on lean NO_x catalysts for application to future gasoline and diesel engines is described. As a result of further improvements in fuel economy, the temperature of exhaust gas will be lower and there will be smaller quantities of hydrocarbons (HCs) in the exhaust of future engines. Therefore, it is necessary to improve the activity of lean NO_x catalysts at lower temperatures and achieve higher selectivity of the NO_x–HC reaction. Utilizing precious metal catalysts is one effective way of improving catalyst activity at lower temperatures, and HC adsorption and reforming are two key technologies for improving the catalyst selectivity for the NO_x–HC reaction.     

High-temperature hydrogen production by solar thermochemical reactors,metal interfaces,and nanofluid cooling

Journal of Thermal Analysis and Calorimetry - Solar thermochemical reactors have been considered in recent studies because of converting the solar energy to a fuel, which is called solar fuel. In...     

Recent synthetic transport systems

This critical review covers progress with synthetic transport systems, particularly ion channels and pores, between January 2006 and December 2009 in a comprehensive manner. This is the third part of a series launched in the year 2000, covering a rich collection of structural and functional motifs that should appeal to a broad audience of non-specialists, including to organic, biological, supramolecular and polymer chemists. Impressive breakthroughs have been achieved over the past four years in part because of a fruitful expansion toward new types of interactions, including metal-organic, π-π, aromatic electron donor-acceptor, anion-π or anion-macrodipole interactions as well as dynamic covalent bonds (169 references).     

Anti-icing systems of the mechanical-draft cooling towers

The possibilities of modern anti-icing systems of cooling towers elaborated for sectional and single mechanical-draft towers with irrigation area 144 m² and 400 m² are shown on the basis of the utilization of particularities of aerodynamic conditions in them.     

Recent lean NOx catalyst technologies for automobile exhaust control

The current status of our development work on lean NO_x catalysts for application to future gasoline and diesel engines is described. As a result of further improvements in fuel economy, the temperature of exhaust gas will be lower and there will be smaller quantities of hydrocarbons (HCs) in the exhaust of future engines. Therefore, it is necessary to improve the activity of lean NO_x catalysts at lower temperatures and achieve higher selectivity of the NO_x–HC reaction. Utilizing precious metal catalysts is one effective way of improving catalyst activity at lower temperatures, and HC adsorption and reforming are two key technologies for improving the catalyst selectivity for the NO_x–HC reaction.     

Evaluation of malodor for automobile air conditioner evaporator by using laboratory-scale test cooling bench

As one of the measures to improve the environment in an automobile, malodor caused by the automobile air-conditioning system evaporator was evaluated and analyzed using laboratory-scale test cooling bench. The odor was simulated with an evaporator test cooling bench equipped with an airflow controller, air temperature and relative humidity controller. To simulate the same odor characteristics that occur from automobiles, one previously used automobile air conditioner evaporator associated with unpleasant odors was selected. The odor was evaluated by trained panels and collected with aluminum polyester bags. Collected samples were analyzed by thermal desorption into a cryotrap and subsequent gas chromatographic separation, followed by simultaneous olfactometry, flame ionization detector and identified by atomic emission detection and mass spectrometry. Compounds such as alcohols, aldehydes, and organic acids were identified as responsible odor-active compounds. Gas chromatography/flame ionization detection/olfactometry combined sensory method with instrumental analysis was very effective as an odor evaluation method in an automobile air-conditioning system evaporator.     

Recent advances in low oxidation state aluminium chemistry

The synthesis and isolation of novel low oxidation state aluminium (Al) compounds has seen relatively slow progress over the 30 years since such species were first isolated. This is largely due to the significant challenges in isolating these thermodynamically unstable compounds. Despite challenges with isolation, their reactivity has been widely explored and they have been utilized in a wide range of processes including the activation of strong chemicals bonds, as ligands to transition metals and in the formation of heterobimetallic M–M compounds. As such, attempts to isolate novel low oxidation state Al compounds have continued in earnest and in the last few years huge advances have been made. In this review we highlight the remarkable recent developments in the low oxidation state chemistry of aluminium and discuss the variety of new reactions these compounds have made possible.

Documenting the synthesis and isolation of novel low oxidation state aluminium (Al) compounds, which until recently has seen relatively slow progress over the 30 years since such species were first isolated.     

固体核磁共振研究分子筛的新进展

分子筛由于具有独特的孔道及可调控酸碱性等特征,被作为离子交换剂、吸附剂及催化剂而广泛应用于石油化工的各种催化过程中。固体核磁共振是研究分子筛结构、酸性及主客体相互作用的强有力谱学手段之一。简单概述了固体核磁共振研究分子筛的最近进展。     

Fabricating an experimental setup to investigate the performance of an automobile car radiator by using aluminum/water nanofluid

In this present work, effect of Al/water nanofluids on the rheological performance of an automobile car radiator has been investigated. Nanofluids were fabricated by two-step methods, i.e., dispersing of aluminum metal bases nanoparticles of size 75–135 nm in double-distilled water. Experiments were conducted on single-pass cross-flow compact heat exchanger by varying the various parameters such as inlet temperature, flow rate through the heat exchanger, concentration of nanoparticles and velocity of air employed for cooling purpose. It was concluded that the hot side Nusselt numbers are improved by 3.37 and 5.0877% for 0.2 and 0.3% concentrations of nanofluids, respectively, at 318.15 K inlet fluids temperature as compared to base fluids. Colburn factor was increased by 12.94 and 23.45% for 0.2 and 0.3% nanoparticles volume concentration of nanofluids, respectively, at 318.15 K inlet temperature with respect to double-distilled water. Hot fluid side friction factor was increased by 14.04 and 20.916% for 0.2 and 0.3% nanoparticles volume concentration of nanofluids with respect to base fluids, but this average value of friction factor was decreased by 2.29 and 9.1412% when temperature was increased from 318.15 to 323.15 K and 328.15 K, respectively.     

Stabilization of cooling water-circulation systems with organophosphorus compounds

Effect of organophosphorus compounds on stability parameters of cooling water-circulation systems was studied using a laboratory setup simulating sedimentation processes under dynamic conditions. It was found that introduction of organophosphates reduces the sedimentation rate by a factor of 2.5–3.5 as compared with a model system containing no inhibitors due to the activation of growth of the less stable polymorphic modification of calcium carbonate.     

Recent developments in detection for microfluidic systems

Microfluidic systems have become more and more important in the field of analytical chemistry. Detection methods on these microsystems are essential for the identification and quantification of chemical species that are being analyzed. This review concentrates on the latest developments of optical detection methods and mass spectrometry in conjunction with microfluidic systems. Electrochemical methods are discussed in another review in the same issue of this journal. Within the optical detection section, topics such as multiplexed detection and the use of waveguides are discussed. Within the discussion of mass spectrometry, the main focus is on electrospray emitters as interfaces between microsystem and spectrometer. Apart from optical detection and mass spectrometry, other techniques such as flame ionization and nuclear magnetic resonance are also mentioned.     

Recent developments in materials synthesis in surfactant systems

The paper reviews the use of surfactant self-assembly to template the synthesis of polymers, ceramics with extended structures, and nanoparticles. The objective of the review is to highlight newer concepts linking self-assembly to materials nanostructure and to the realization of functional materials.     

Preparative solid state chemistry. Recent developments

A survey of recent developments in preparative solid state chemistry shows that, with a knowledge of structural chemistry and reactivity patterns of solids, it is possible to synthesize a variety of new solids possessing novel structures. A distinction is made between synthesis ofnew solids and synthesis of solids bynew methods. Three new routes to solid state synthesis are recognized: the precursor method, and topochemical methods involving redox and ion-exchange reactions. The low-temperature topochemical methods enable synthesis of metastable phases that are inaccessible by the high temperature route. Several illustrative examples of solid state synthesis from the recent literature are presented.