Conduction calorimetric analysi

Conduction calorimetric analysis has also been carried out on the effect of sugar-free lignosulfonate on the hydration of cement. It was found that sugar-free lignosulfonate was nearly as efficient as commercial lignosulfonate in retarding rate of reaction and setting of cement. 

For the sorption experiments, an accurately weighed sample of approximately 30 mg of the powder was placed in a 4-ml stainless steel sealed ampoule. Prior to calorimetric analysis, the sample was dried overnight under dry nitrogen flow (—0% RH) until a signal of zero heat flow was attained. With every rim, a blank experiment was conducted under identical conditions using an empty ampoule. The calorimetric adsorption... 

In the later stage, a calorimetric analysis (DSC) of the cure kinetics of the same glass/epoxy composite was conducted for both thermal and microwave curing... 

Work with cations includes examination of the viscosity effects of sodium and potassium halides on solutions of xylose (structure-making and structurebreaking trends were studied), calorimetric analysis of the interaction of calcium ions with D-galactose, myo-inositol, and lactose, and conductance... 

Imre AW, Schonhoff M, Cramer C (2008) A conductivity study and calorimetric analysis of dried poly(sodium 4-styrene sulfonate)/poly(diallyldimethylammonium chloride) polyelectrolyte complexes. J Chem Phys 128 134905... 

An understanding of the complex physico-chemical phenomena associated with the formation and behavior of cementitious compounds is facilitated through the application of many different types of investigative methods. Techniques such as NMR, XRD, neutron activation analysis, atomic absorption spectroscopy, IR/UV spectroscopy, electron microscopy, surface area techniques, pore characterization, zeta potential, vis-cometry, thermal analysis, etc., have been used with some success. Of the thermal analysis techniques the Differential Thermal Analysis (DTA), Thermogravimetric Analysis (TG), Differential Scanning Calorimetry (DSC), and Conduction Calorimetric methods are more popularly used than others. They are more adaptable, easier to use, and yield important results in a short span of time. In this chapter the application of these techniques will be highlighted and some of the work reported utilizing other related methods will also be mentioned with typical examples. 

The kinetic techniques were densitometry and reaction calorimetry, and the electrical conductivity, K, was monitored for most systems the calorimetric measurements also yielded the enthalpies of polymerisation (AHp). Analysis of the polymers provided information on initial groups, DP, and DPD for many of the products. The determination of the quantity and origin of kinetically significant impurities is a feature of this work, because much of it was done with initiator concentrations, c0, between 10 4 and 10"3 mold"1, and the measured impurity levels, c , ranged from 10"4 down to 10"5 mold 1. 

The nature of donor-acceptor complexes has been the subject of various NMR studies conducted as early as the 1960s. Early calorimetric studies showed that boron trihalides are capable of forming donor-acceptor complexes with a number of Lewis bases and the heats of adduct formation for some of these complexes were determined. Gaseous boron trifluoride, for example, was shown to form a ctxnplex with ethyl acetate in a highly exothermic reaction (-A// = 32.9 0.2 kcal mol ). IR and UV analysis of BF3 complexes of aromatic aldehydes indicated a o-complex with a lengthened CVO bond and a highly delocalized ir-system. More detailed structural information, however, was acquired only after closer inspection by low temperature H, B, C and F NMR studies. ... 

It must be emphasized that this analysis is not possible without prior knowledge of the thermal volume of the calorimetric cell and therefore the validation routine described above must be conducted if accurate values for the enthalpy in particular are to be obtained. 

Recently, the influence of gas adsorption on physical properties of carbon nanotubes has attracted a considerable interest. It is caused by a possibility to create gas nanosensors [1,2]. The analysis of calorimetric data has shown that the gas adsorption in space between nanotubes gives the main effect on physical properties [3]. The measurement of the conductivity is simple and convenient method to detect a response of multiwalled nanotubes with respect to an external influence. This response can be used to construct a resistive sensor. 

The elemental composition of the raw peat and solid product was determined using an elemental analyzer (Yanaco CHN Corder MT-5 and MT-6). Additionally, proximate analysis (based on JIS M 8812) total sulfur analysis (based on JIS M 8819) and calorific analysis (based on JIS M 8814) were conducted separately. The gross calorific value (CV) was measured using the bomb calorimetric method and the effective calorific value (ECV) of the sample at a constant pressure was determined based on JIS M 8814, which is followed by ISO 1928. The equilibrium moisture content of the dried solid product was further analyzed while maintaining their moisture contents according to JIS M 8811. Briefly, an aliquot of the sample was placed inside a desiccator containing saturated salt solution and then measured rapidly using a moisture content analyzer (Sartorius MA 150). 

Chapter 4 describes the fundamental principles for conducting a kinetic analysis of calorimetric results. The aim of a thermokinetic analysis is the elaboration of the fundamental rules that set the tone for running a chemical conversion in liquid, homogeneous reaction mixtures, i.e.. 

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