Provided are an attachment for liquid sample measurement which is capable of effectively reducing a consumption amount of a liquid sample, a refractive index measuring device and a refractive index measuring method. An attachment (100) is disposed on a V-block prism (1) formed on a V-shaped groove (11) for keeping a sample so as to enter the groove (11). A body (110) of the attachment (100) forms an enclosing space (107) for enclosing the liquid sample between the body and a surface of the groove (11) formed on the V-block prism (1), and makes the liquid sample enclosed in the enclosing space (107) contact directly with the surface of the groove (11).

A method of reducing noise in an output signal of a differential refractive index detection part (RI detection part) of a dual-flow type with an analysis device having the RI detection part includes sending a sample liquid to a sample cell with a sample pump, sending a reference liquid to a reference cell with a reference pump, and detecting a change in direction of travel of light sequentially transmitted through the two cells with a light detector. Before starting RI measurement, a phase difference between the sample pump and the reference pump is adjusted so that a noise that occurs in an output signal of the light detector by propagation of pulsation from the sample pump within the sample cell and a noise that occurs in the output signal of the light detector by propagation of pulsation from the reference pump within the reference cell cancel each other.

An optical oil component sensor and a sensing method using the sensor, which can identify similar fuel oil in real time. The optical oil component sensor includes a light source unit, a reference optical waveguide, configured to guide light thereinto, for receiving and outputting light emitted from the light source unit, a sensing optical waveguide, configured to guide light thereinto, for receiving and outputting light emitted from the light source unit, wherein a portion of the sensing optical waveguide is formed to be in contact with test target oil, a light-receiving unit for receiving both a reference light signal, output from the reference optical waveguide, and a test light signal, output from the sensing optical waveguide, and a control unit for identifying components of the test target oil by comparing optical properties of the reference light signal and the test light signal with each other.

Provided are an attachment for liquid sample measurement which is capable of effectively reducing a consumption amount of a liquid sample, a refractive index measuring device and a refractive index measuring method. An attachment (100) is disposed on a V-block prism (1) formed on a V-shaped groove (11) for keeping a sample so as to enter the groove (11). A body (110) of the attachment (100) forms an enclosing space (107) for enclosing the liquid sample between the body and a surface of the groove (11) formed on the V-block prism (1), and makes the liquid sample enclosed in the enclosing space (107) contact directly with the surface of the groove (11).

A flow cell for differential refractive index detection. The flow cell includes a transparent body that extends from a first end to a second end along a longitudinal axis. The transparent body defines a sample prism chamber and reference prism chamber. The sample prism chamber is configured to allow fluid flow between the first and second ends of the transparent body along the longitudinal axis. The reference prism chamber is configured to receive a reference fluid. The sample and reference prism chambers each include a grating comprising a plurality of grooves extending along the longitudinal axis in the direction of fluid flow.

An embodiment of a refractive index detector includes a sample cell, a reference cell, a measurement section, a liquid inlet port, liquid outlet sections, and a switching mechanism. The inlet port leads to a sample cell inlet. A first outlet port and a second outlet port are for discharging a liquid. The switching mechanism includes a reference liquid supply mode for forming a channel for connecting a reference cell outlet to one of the first outlet port and the second outlet port while connecting a sample cell outlet to a reference cell inlet, and an analysis mode for forming a channel for connecting the sample cell outlet to one of the first outlet port and the second outlet port while sealing the reference cell outlet.

The invention provides differential refractive index detectors and methods for the use of differential refractive index detectors. In an exemplary embodiment, a differential refractive index detector includes a flow cell body having a proximal end, a distal end, and a flow axis extending between the proximal and the distal end. The flow cell body includes a first chamber and a second chamber and the fluid conduits coupled to the flow cell body can be tapered to reduce dispersion.

A differential refractometer including a measurement section for measuring the diffractive index difference between a sample cell and a reference cell by radiating light on a measurement cell and detecting light which has sequentially passed through the sample cell and the reference cell includes a mobile phase supply section for delivering a mobile phase in a sample introduction channel that is connected to the sample cell. The mobile phase supply section includes a mobile phase container for containing the mobile phase. The inside of the mobile phase container is continuously stirred by a stirring mechanism, and the composition of the mobile phase inside the mobile phase container is made uniform.

The invention provides differential refractive index detectors and methods for the use of differential refractive index detectors. In an exemplary embodiment, a differential refractive index detector includes a flow cell body having a proximal end, a distal end, and a flow axis extending between the proximal and the distal end. The flow cell body includes a first chamber and a second chamber and the fluid conduits coupled to the flow cell body can be tapered to reduce dispersion.

An optical oil component sensor and a sensing method using the sensor, which can identify similar fuel oil in real time. The optical oil component sensor includes a light source unit, a reference optical waveguide, configured to guide light thereinto, for receiving and outputting light emitted from the light source unit, a sensing optical waveguide, configured to guide light thereinto, for receiving and outputting light emitted from the light source unit, wherein a portion of the sensing optical waveguide is formed to be in contact with test target oil, a light-receiving unit for receiving both a reference light signal, output from the reference optical waveguide, and a test light signal, output from the sensing optical waveguide, and a control unit for identifying components of the test target oil by comparing optical properties of the reference light signal and the test light signal with each other.