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This article reports the results of an investigation into the transfer of thermal probe measurement technology from laboratory use to actual buildings in order to undertake the in situ determination of thermal material properties. The imperative for using in situ measurements is 1) the impact of moisture content on thermal properties, 2) the possible wide range of variation of properties across most materials used in construction, and 3) the lack of data for new and innovative materials. Thermal probe technology offers the prospect of taking building specific data, addressing these issues.Based on commercially available thermal probes a portable measurement kit and accompanying measurement procedure have been developed. Three case study buildings, each having different materials, have been studied to ascertain whether or not the technique can be transferred to relatively uncontrolled environments while remaining capable of achieving a precision that is similar to an ASTM standard that can be related to thermal conductivity measurements of building materials. The results show that this is indeed the case, and that the use of thermal probe technology may yield thermal properties that vary significantly from the laboratory values currently used in building thermal engineering calculations.Keywords: thermal probe; measuring building material properties, thermal conductivity, energy use, earth buildings, cob. The rationale for in situ thermal measurements Energy use in buildings has a significant effect on the global environment with some 15% of UK greenhouse gas emissions attributable solely to the heating of domestic properties DTI (2002). Reduced energy consumption in buildings, whether existing or proposed, requires reliable data on the thermal properties of building materials. This data is now invariably obtained from measurements carried out on samples under laboratory conditions and not from in situ measurements, which gives rise to the following 3 problems in practice:(a) The moisture content of the representative material sample used in laboratory studies can have a significant effect on its effective thermal conductivity Salmon, et al (2002), and may be different to that of the actual material in the building on site and under actual use conditions.(b) The steady state techniques, such as guarded hot plate or two box methods, commonly used in laboratory measurements, require long times to achieve thermal equilibrium. As shown by Doran (2000), during this time, moisture present within typically hygroscopic building materials migrates and evaporates, resulting in altered thermal properties.(c) A material sample used in the laboratory may not share all qualities of the bulk material on site through varied manufacturing processes and/or differences in raw P o s t -P r i n t 3 materials. As an example, a standard reference work Touloukian, et al (1970) Davis (1984); it has been successfully applied to building materials under laboratory conditions by Goodhew and Griffiths (2004).However, when this met...

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Cispentacin is the 1R, 2S enantiomer of 2-aminocyclopentanecarboxylic acid (Fig. 1, 1 X \ CH 2 ). It was isolated independently by two groups from Bacillus cereus1 and Streptomyces setonii2 and shown to exhibit potent antifungal activity in vivo against Candida albicans.The racemic compound was also claimed to exhibit activity against pathogens of agrochemical interest,3 and a sample was prepared and tested at JealottÏs Hill. Interesting levels of antifungal activity were observed against Phycomycete pathogens both in the glasshouse and in the Ðeld and hence a series of analogues were prepared.It was envisaged that 4-substituted analogues of type 1 would be accessible using the chemistry outlined in Scheme 1 (Fig. 1), in which the amino functionality is introduced by Curtius reaction of the half-acid derived from an appropriate meso-diester. Scheme 2 illustrates this approach for the carbocyclic series. The diester 3 was prepared by oxidation followed by Ruzsicka-type * To whom correspondence should be addressed cyclisation of the diester 2, a modiÐcation of chemistry originally developed by Gais et al.4 Hydrogenation of 3 selectively removed the benzyl group to give the desired half-ester 4. Curtius reaction with diphenylphosphoryl azide gave solely the allophanate 5, but use of trimethylsilyl azide on the corresponding acid chloride under carefully controlled conditions gave the desired carbamates in yields up to 70%. Analogues 7È11 are representative of the targets synthesised using this chemistry. The stereochemistry of the Curtius reaction was proved by removal of the keto-group in 6 by Clemmensen reduction and comparison with the appropriate protected cispentacin.The Curtius chemistry was extended to the synthesis of other substituted analogues (Fig. 2, Scheme 3). The cyclopentane ring was Ðrst built up by annulation of 1,2-bis(4,4-dimethyl-2-oxazolin-2-yl)ethane with propanes bearing 1,3-leaving groups in the manner described by Yamamoto.5 The trans-cyclopentane-1,2-diacids thus available could be converted to the corresponding cis-anhydrides by heating with propionic anhydride. The desired analogues were then available by application of the chemistry previously described. The 4-spirocyclopropyl analogue was, for example, one compound approached using this method.The 1,3-dipolar cycloaddition chemistry envisaged for the synthesis of 4-heterosubstituted analogues (Scheme 1) was successful only in the case of nitrogen substitution. Scheme 4 (Fig. 2) shows how this chemistry was reduced to practice. The desired sulfur analogues were Ðnally prepared by oximation/reduction of the Dieckmann adduct, 2-methoxycarbonyl-3-oxotetrahydrothiophene.The equivalent oxygen-substituted 329 1997 SCI. Pestic. Sci. 0031-613X/97/$17.50. Printed in Great Britain (

Transient line source measurements have been employed in various industries, e.g., plastics, foodstuffs, and refractory bricks, to measure thermal conductivity and sometimes thermal diffusivity. Measurements have traditionally been carried out in carefully controlled thermal environments. In pursuance of better data to inform energy efficiency calculations for building envelopes, a transient line source using thermal probe technology is assessed for in situ measurements, where materials may be subject to varied moisture content under diverse environmental conditions. A robust stand alone field apparatus has been developed. Laboratory based measurements have been undertaken, and results are reported for agar immobilized water and polytetrafluoroethylene, as well as aerated concrete and oak at specific moisture contents. The field apparatus was used to measure in situ the thermal properties of walls in real buildings, one of aerated concrete and one of mass earth construction. A new and simplified method of identifying appropriate analysis time windows has been developed, which allows an assessment of confidence levels in thermal conductivity results. Thermal diffusivity results were discounted as the effects of contact resistance between the probe and sample could not be differentiated from the heat capacity effects of the sample material. Valid thermal conductivity results were achieved for reference materials containing moisture and in situ measurements. The in situ thermal conductivity values were shown to be at significant variance with design values. Consistent thermal conductivity results were achieved for common building materials above 0.15 W⋅m −1⋅K−1, and indicative results were achieved for values below this despite measurements being taken under varying environmental conditions. The principal cause of error in the measurement of materials with higher thermal resistance was identified.