The thermal, electrical, and thermoelectric properties of aerogels of single-walled carbon nanotubes are characterized. Their ultralow density enables the transport properties of the junctions to be distinguished from those of the nanotubes themselves. Junction thermal and electrical conductances are found to be orders of magnitude larger than those found in typical dense SWCNT networks. In particular, the average junction thermal conductance is close to the theoretical maximum for a van der Waals bonded SWCNT junction.

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As disinfection by-products, the taste and odor (T&O) compounds were produced by chlorination at the end of water treatment. The existence of T&O compounds causes the pipe water with unpleasant odor and reducing water quality. Based on the latest research achievements at home and abroad, the characteristics and formation mechanisms of typical T&O compounds produced by chlorination are introduced. The new analytical method of electronic nose is also expounded. In addition, the common control technologies, such as pre-oxidation, activated carbon adsorption and bio-membrane, are reviewed. Since the precursors of T&O compounds shows small molecular, stable structure and low concentration, some coupling technologies including ozone-GAC, permanganate-PAC, and bio-membrane and GAC treatments, are employed effectively.Key words: chlorination; odor and taste compounds; disinfection by-products; precursor; electronic nose

Fishy odor, part of the taste and odor existing in the drinking water, often cause people to reflect poor water quality, and even lead to social panic. The typical fishy compounds are primarily amines and polyunsaturated aldehydes (PUAs), which are widely found in surface water, particularly during the algae blooms. The properties of the small molecular weight, low odor threshold and difficult removing, have received a great concern in the field of environment protection. Because of their environmental hazards, the source, physical-chemical properties, genotoxicity and generation mechanism of the fishy compounds were introduced in this paper in order to remove the compounds by controlling the precursors and generation pathway. The results show that amines are produced by the nitrogenous compounds in catalysis of microorganisms and enzymes, while PUAs are produced by polyunsaturated fatty acids (PUFAs). The algal cells cleavage is a key factor of producing fishy odor.

This study examined effects of various blending ratio of desalinated water and tap water on iron release. Pipe rig tests were conducted to simulate and demonstrate iron release in response to water quality changes. Results show that compare to conventional treated water, desalinated water has a pronounced effect on the iron release in ductile iron pipe; increasing fractions of desalinated water in the blends result in higher total iron release. An increase in pH from 8.0 to 10.0 after 24 hours was found due to alkaline substances (like calcium oxide) releasing from the cement mortar lining and the poor buffering capacity of desalinated water.