The invention relates to a calorimeter including at least one measurement sensor (4) for receiving at least one sample, and at least three stages (1, 2, 3) for controlling the temperature, with decreasing size, each including a mounting (10, 20, 30) and means for controlling the temperature, the smallest stage being associated with said at least one sensor (4), in which: a first stage (1) also includes a screen (11) forming a first enclosure with the mounting (10) of said first stage; a second stage (2) is placed inside (12) said first enclosure and the mounting (20) thereof is thermally coupled with the mounting (10) of the first stage by first thermal conductances (23) comprising Peltier elements; and a third stage (3) is placed inside the second enclosure defined by the second stage and is thermally coupled with said second stage (2) by second passive thermal conductances (33) defining an adapted time-constant value.

Methods of preparing high-density polyethylene (HDPE) nanocomposites by in situ polymerization with a zirconocene catalyst, a methylaluminoxane cocatalyst, a calcium zirconate nanofiller in a solvent. The calcium zirconate nanofiller, which is dispersed across the polyethylene matrix, is found to enhance catalyst activity, and other properties of the HDPE nanocomposites produced, including but not limited to flame retardency, crystallinity and surface morphology.

Methods of preparing high-density polyethylene (HDPE) nanocomposites by in situ polymerization with a zirconocene catalyst, a methylaluminoxane cocatalyst, a calcium zirconate nanofiller in a solvent. The calcium zirconate nanofiller, which is dispersed across the polyethylene matrix, is found to enhance catalyst activity, and other properties of the HDPE nanocomposites produced, including but not limited to flame retardency, crystallinity and surface morphology.

The differential adiabatic compensation calorimeter comprises sample and reference containers, sample and reference temperature sensors connected back-to-back, in series, sample and reference compensating heaters coupled to the sample and reference containers, and a temperature-controlled chamber. In this differential adiabatic mixing and reaction calorimeter, the sample heat-sink heat loss to the sample container is compensated so that the exothermic reaction is conducted in an adiabatic state, resulting in an undistorted adiabatic process gaining the highest adiabatic temperature rise that corresponds to the theoretical value and an experimentally measured time to maximum rate value. The calorimeter is designed for measuring the time-resolved adiabatic temperature rise, the rate of temperature rise, the time to maximum temperature peak and time to maximum rate of an exothermic chemical reaction.

The differential adiabatic compensation calorimeter comprises sample and reference containers, sample and reference temperature sensors connected back-to-back, in series, sample and reference compensating heaters coupled to the sample and reference containers, and a temperature-controlled chamber. In this differential adiabatic mixing and reaction calorimeter, the sample heat-sink heat loss to the sample container is compensated so that the exothermic reaction is conducted in an adiabatic state, resulting in an undistorted adiabatic process gaining the highest adiabatic temperature rise that corresponds to the theoretical value and an experimentally measured time to maximum rate value. The calorimeter is designed for measuring the time-resolved adiabatic temperature rise, the rate of temperature rise, the time to maximum temperature peak and time to maximum rate of an exothermic chemical reaction.

Disclosed are systems and methods for providing an adiabatic power compensation differential scanning calorimeter to minimize a temperature difference between a sample and a reference. For instance, methods can include providing ramp-up heating power to heat a sample container and a reference container based on a preprogrammed temperature ramp rate; minimizing a temperature difference among the sample container, the reference container, and at least one furnace; providing compensating heat to the sample container and the reference container when a self-heating activity of the sample material is detected; providing container-only compensating heat to the sample container to block heat transfer from the sample material to the sample container once the self-heating activity of the sample material is detected; and providing compensating heat to the reference container to facilitate container-only compensating heat calculation and control.

Disclosed are systems and methods for providing an adiabatic power compensation differential scanning calorimeter to minimize a temperature difference between a sample and a reference. For instance, methods can include providing ramp-up heating power to heat a sample container and a reference container based on a preprogrammed temperature ramp rate; minimizing a temperature difference among the sample container, the reference container, and at least one furnace; providing compensating heat to the sample container and the reference container when a self-heating activity of the sample material is detected; providing container-only compensating heat to the sample container to block heat transfer from the sample material to the sample container once the self-heating activity of the sample material is detected; and providing compensating heat to the reference container to facilitate container-only compensating heat calculation and control.

A differential calorimeter with flux measurement to measure a heat flux emitted by radioactive materials contained in a container, including: a measurement cell including measurement plates distributed around a container reception containment; and a reference cell including reference plates and a reference sample. The reference plates are placed behind the measurement plates from the container when the container is in the reception containment and the reference sample is under the reception containment.

A differential calorimeter with flux measurement to measure a heat flux emitted by radioactive materials contained in a container, including: a measurement cell including measurement plates distributed around a container reception containment; and a reference cell including reference plates and a reference sample. The reference plates are placed behind the measurement plates from the container when the container is in the reception containment and the reference sample is under the reception containment.

It is an object of the present invention to provide a calorific value measuring device and a calorific value measuring method which enable highly reliable measurement of the calorific value of a by-product gas produced in a steelmaking process. In the present invention, with a by-product gas produced in a steelmaking process being employed as an object gas of which calorific value is to be measured, the refractive index and the sonic speed of the by-product gas are measured so as to compute a refractive index equivalent calorific value Q.sub.O from the value of the refractive index as well as a sonic speed equivalent calorific value Q.sub.S from the value of the sonic speed. On the basis of the concentration X.sub.CO of carbon monoxide gas contained in the by-product gas, an error calorific value Q.sub.CO is computed by Equation (1) below using a value selected within a range of 0.08 to 0.03 as a calorific value equivalent coefficient . On the basis of the refractive index equivalent calorific value Q.sub.O, the sonic speed equivalent calorific value Q.sub.S and the error calorific value Q.sub.CO which have been computed, the calorific value Q of the by-product gas is determined by Equation (2) below using a value selected within a range of 1.1 to 4.2 as a correction factor .

[00001]$\begin{array}{cc}{Q}_{\mathrm{CO}}=X_{\mathrm{CO}}.Math.& \mathrm{Equation}.Math..Math.\left(1\right)\\ Q=Q_0-\frac{Q_0-Q_S}{1-}-Q_{C.Math..Math.0}& \mathrm{Equation}.Math..Math.\left(2\right)\end{array}$