Fuel compositions that are low sulfur and have adequate combustion quality are disclosed. An example fuel composition that is low sulfur may have the following enumerated properties: a sulfur content of about 0.50% or less by weight of the fuel composition; a calculated carbon aromaticity index of about 870 or less; a density at 15° C. of about 900 kg/m.sup.3 to about 1,010 kg/m.sup.3; a kinematic viscosity at 50° C. of about 100 centistokes to about 700 centistokes; and an estimated cetane number of about 7 or greater.

A method for measuring the oil content of a lithium battery separator by using DSC includes the following steps: taking 5-10 mg of an oil-containing separator sample from the lithium battery separator, and taking 5-10 mg of an oil-free separator sample from an oil-free separator; performing an enthalpy test on the oil-free separator sample at room temperature by using a differential scanning calorimeter to obtain a first enthalpy value, and performing an enthalpy test on the oil-containing separator sample by using the differential scanning calorimeter to obtain a second enthalpy value; subtracting the second enthalpy value from the first enthalpy value to obtain a difference, and then dividing the difference by the first enthalpy value to obtain the oil content of the oil-containing separator sample.

A gas monitor apparatus includes a sorbent material that adsorbs a target gas based on a concentration of the target gas in a monitored environment and a reference material that does not respond to the target gas. The gas monitor also includes a first thermistor disposed within the sorbent material and a second thermistor disposed within the reference material, the first thermistor to provide a first indication of a first temperature of the sorbent material and the second thermistor to provide a second indication of a second temperature of the reference material. A processing device determines a concentration of the target gas based at least in part on a differential measurement between the first temperature and the second temperature.

Systems and methods are provided for using differential scanning calorimetry (DSC) to predict properties of fuel compositions, such as marine fuel oils. It has been discovered that various features of the data plots generated by DSC can be correlated with properties of interest for marine fuel oil compositions. The fuel composition properties that can be predicted based on DSC include, but are not limited to, density; micro carbon residue; pour point; and estimated cetane number (ECN). This can include prediction of ECN for resid-containing fuel compositions. Using DSC to predict ECN can reduce or minimize the number of resid-containing fuel oil samples that require testing using the limited availability equipment required for the IP 541 method.

Fuel compositions that are low sulfur and have adequate combustion quality are disclosed. An example fuel composition that is low sulfur may have the following enumerated properties: a sulfur content of about 0.50% or less by weight of the fuel composition; a calculated carbon aromaticity index of about 870 or less; a density at 15 C. of about 900 kg/m.sup.3 to about 1,010 kg/m.sup.3; a kinematic viscosity at 50 C. of about 100 centistokes to about 700 centistokes; and an estimated cetane number of about 7 or greater.

A gas monitor apparatus includes a sorbent material that adsorbs a target gas based on a concentration of the target gas in a monitored environment and a reference material that does not respond to the target gas. The gas monitor also includes a first thermistor disposed within the sorbent material and a second thermistor disposed within the reference material, the first thermistor to provide a first indication of a first temperature of the sorbent material and the second thermistor to provide a second indication of a second temperature of the reference material. A processing device determines a concentration of the target gas based at least in part on a differential measurement between the first temperature and the second temperature.

A fluid sensor for sensing a concentration or composition of a fluid, the sensor comprising: a semiconductor substrate comprising a first etched portion and a second etched portion; a dielectric region located on the semiconductor substrate, wherein the dielectric region comprises a first dielectric membrane located over the first etched portion of the semiconductor substrate, and a second dielectric membrane located over the second etched portion of the semiconductor substrate; two temperature sensing elements on or within the first dielectric membrane and two temperature sensing elements on or within the second dielectric membrane; an output circuit configured to measure a differential signal between the two temperature sensing elements of the first dielectric membrane and the two temperature sensing elements of the second dielectric membrane; wherein the first dielectric membrane is exposed to the fluid and the second dielectric membrane is isolated from the fluid.

A gas sensor (1) including a first gas detection element (2) and a second gas detection element (3), a first storage portion (4) having a first internal space (4A), and a first opening (4B) establishing communication between the first internal space (4A) and the outside space thereof exposed to a detection subject atmosphere, a second storage portion (5) having a second internal space (5A) and a second opening (5B) establishing communication between the second internal space (5A) and the outside space, a first membrane (4C) allowing permeation of water vapor and substantially not allowing permeation of a detection target gas, and covering the first opening (4B), and a calculation unit (12) for calculating the concentration of a detection target gas contained in the detection subject atmosphere, based on outputs from the first and second gas detection elements (2, 3), respectively.

The aim of the invention is to provide a commercially usable and inexpensive device and method with which a sorption enthalpy can be measured in a simple manner. This is achieved by a device for calorimetrically measuring sorption processes, comprising a sorption cell for receiving a sample, the sorption cell having a volume for filling with a sorption gas, and comprising a reference cell likewise for filing with the sorption gas. A measurement gas volume is arranged around the sorption cell for receiving a reference gas, and the reference cell is surrounded by a reference gas volume, which is likewise provided for receiving the reference gas. A gas connection is provided between the sorption cell and the reference cell in order to conduct sorption gas into the sorption cell and the reference cell such that a sorption reaction occurs with the sample in the sorption cell. Furthermore, a device is provided for measuring pressure differences between the measurement gas volume and the reference gas volume in order to carry out a calorimetric measurement of the sorption process on the sample in the sorption cell on the basis of a volume change of the reference gas in the measurement gas volume.

A fluid sensor for sensing a concentration or composition of a fluid, the sensor comprising a first temperature sensing element located on or within a first dielectric membrane and a second temperature sensing element located on or within a second dielectric membrane. An output circuit is configured to measure a differential signal between the first temperature sensing element and the second temperature sensing element. The fluid sensor comprises a first region configured to be exposed to the fluid, and a second region configured to be isolated from the fluid, where the first dielectric membrane is located in the first region, such that in use, the first dielectric membrane is exposed to the fluid, and wherein the second dielectric membrane is located in the second region such that in use, the second dielectric membrane is isolated from the fluid.