A simple adiabatic calorimeter has been made to investigate the heat capacity of small samples (≤ 1 cm 3 ) of carbon nanomaterials in the temperature range from 1 to 300 K. It makes possible: i) short-time mounting of a sample; ii) doping of samples with gases directly in the calorimeter; iii) short-time cooling of a sample down to helium temperatures. The adiabatic calorimeter is suitable to place into a helium vessel of a portable Dewar or a helium cryostat. The heat capacity of the fullerit sample has been measured in the temperature range from 1 to 30 K. PACS: 81.05.U-Carbon/carbon-based materials; 65.40.Ba Heat capacity.

Thermal conductivity of crystalline natural nitrogen was investigated over the temperature range 1.2 -38 K. The temperature dependence of thermal conductivity of a-nitrogen has been determined in temperatures below 18 K. The thermal conductivity coeScient reaches the maximum value 250 mW/cm K at 3.6 K. The results of the experiment below 14 K can be well described by integral equation obtained by the method of Callaway. Relaxation times for various mechanisms of phonon scattering have been determined. The results of our experiments are in accord with earlier literature data for temperatures above 18 K.

The specific heat at constant pressure C(T) of bundles of single-walled carbon nanotubes (SWNTs) closed at their ends has been investigated in a temperature interval of 2 -120 K. It is found that the curve C(T) has features near 5 K, 36 K, 80 K and 100 K. The experimental results on the C(T) and the radial thermal expansion coefficient  R (T) of bundles of SWNTs oriented perpendicular to the sample axis have been compared. It is found that the curves C(T) and  R (T) exhibit a similar temperature behavior at T>10 K. The temperature dependence of the Gruneisen coefficient (Т) has been calculated. The curve (Т) also has a feature near 36 K. Above 36 K the Gruneisen coefficient is practically independent of temperature (4). Below 36 K (Т) decreases monotonically with lowering temperature and becomes negative at T< 6 K. PACS: 65.40.Ba Heat capacity; 65.80.-g Thermal properties of small particles, nanocrystals, nanotubes, and other related systems; 81.07.De Nanotubes.