Abstract: The present disclosure relates to light arrangement for an optical device for measurement of an index of refraction, having a light source, a fiber bundle arrangement for transmitting light from the light source, a diffusing member, and imaging optics for transmitting the light to a measuring window. In order to provide for an arrangement which is durable and accurate even when used for measuring hot specimens where the light source is positioned far from the measuring window, the fiber bundle arrangement includes a novel combination of a first fiber bundle and a second fiber bundle.

Abstract: A sealing arrangement and method of a measuring device are disclosed, the measuring device having one or more measuring elements that have a surface in contact with a fluid being measured, a fluid chamber for the fluid being measured, and a seal to seal the joint between the fluid chamber and the measuring element. Flow channels have been formed in the measuring device to lead the rinsing fluid in contact with the seal.

Abstract: An optical measuring device including a measuring head, an inner shell including a light transmitter and a light receiver, an outer shell including a measurement orifice in one end and a fastening flange part in another end, the inner shell is arranged at least partially in the outer shell, the measuring head is arranged in the outer shell and attached to the measurement orifice from its first end and to an end of the inner shell from its second end, a gasket is arranged between the measuring head and the measurement orifice, and inside the outer shell is arranged a fluid flow path extending from the gasket towards the fastening flange part, wherein to the outer shell is formed a leak detection port having one end opening into the fluid flow path and another end opening into a side surface of the outer wall in the fastening flange part wherein a fastening flange protrudes between the opening into the side surface and the measurement orifice.

Abstract: An arrangement and method are disclosed for inserting and removing a head of a measuring device to and from a process space. The arrangement includes a measuring device with a measuring head and a retractor tool connected to a valve member. The retractor tool includes rails, a cradle for receiving the measuring device and arranged to slide along the rails, and a driving mechanism for moving the cradle. A valve lock mechanism prevents opening of the valve member if the measuring device is not at a location barring a fluid flow from the process space, and the head of the measuring device is insertable to the process space when the measuring device is received in the cradle.

Abstract: An exemplary arrangement includes a prism-shaped measuring window, which has a measuring surface adapted to contact a substance being measured. A first surface is adapted to direct light originating from a light source to the measuring surface through the measuring window. A second surface is adapted to direct totally reflected light from an interface between the measuring surface in contact with the substance being measured and a substance being measured outside of the measuring window. A first lens arrangement is adapted to focus the light from the light source on the first surface. A second lens arrangement is adapted to focus the totally reflected light passing through the second surface to a device used for analysis. A lens in each of the first and second lens arrangements closest to the measuring window is integrated into the measuring window and establishes optical refractive power in the first and second surfaces.

Abstract: A membrane device for defining interface between first and second environments and for selectively passing through at least one component of a solution of at least two different components from the first environment to the second environment comprises at least one first film layer structure, and at least one second film layer structure. The first layer structure comprises first hydrophobic material, the contact angle of which between the first hydrophobic material and water is more than 90°. In addition, the second film layer structure comprises second hydrophobic material, the contact angle of said second hydrophobic material and water being not greater and advantageously less than said contact angle between said first hydrophobic material and water. The membrane device comprises advantageously also a support structure for supporting at least one of said film layer structure. The support structure is e.g. a polypropylene or stainless-steel mesh, and the support structure as a whole is porous structure.

Abstract: An arrangement for determining concentration of at least two sample components in solution of at least three components comprises a refractometer as a first instrument for measuring refractive index data as a first quantity of the first sample component. In addition the arrangement comprises a second physical quantity measuring device for measuring second physical quantity as a second quantity data of the second sample component, such as a device for measuring conductivity. The second physical quantity is advantageously essentially independent on said refractive index, but is more strongly dependent on at least concentration of at least one second sample component of said solution. Further the arrangement comprises a data processing unit for determining said concentration of at least two sample components by using said refractive index data and second quantity data in an additive way after a variable substitution performed by said data processing unit on the refractive index data.

Abstract: A sealing arrangement and method of a measuring device are disclosed, the measuring device having one or more measuring elements that have a surface in contact with a fluid being measured, a fluid chamber for the fluid being measured, and a seal to seal the joint between the fluid chamber and the measuring element. Flow channels have been formed in the measuring device to lead the rinsing fluid in contact with the seal.

Abstract: A method and an arrangement are disclosed in connection with a measurement arrangement of optical parameters of a separate sample taken from a process liquid, in which method a sample is taken from the process liquid. The sample can be arranged into a sample vessel provided with at least one measurement window, and optical parameters of the sample in the sample vessel are measured through the measurement window. In the sample in the sample vessel, a flow is produced which can be used to mitigate (e.g., prevent) the measurement window surface in contact with the sample from getting dirty. A back-and-forth flow can be produced in the sample residing in the sample vessel by means of pressure variation focused on the sample, and the back-and-forth flow can be focused on the surface of the optical measurement window.

Abstract: An exemplary method for measuring a refractive index of a substance being measured through an optical window, includes arranging the optical window in contact with the substance being measured, directing light to the interface of the optical window and substance being measured, where part of the light is absorbed by the substance being measured and part of it is reflected from the substance being measured to form an image, in which the location of the boundary of light and dark areas expresses a critical angle of the total reflection dependent on the refractive index of the substance being measured, and examining the formed image. Light is directed on a first structure and to desired angles on an interface between the optical window and substance being measured. Light reflected from the interface of the optical window and substance being measured is directed on a second structure.

Abstract: Method and device for measuring the Abbe number in a process liquid. Light generates successively at wavelengths of 486.1 nm, 589.3 nm and 656.3 nm and different light wavelengths are directed successively through a measuring window in the process liquid so total reflection occurs at each wavelength on the measuring window surface and process liquid. Partial light reflected at each wavelength is directed to a sensor, whereby an image forms on the sensor surface; between light and dark boundary region corresponding to each wavelength critical angle, in which total reflection occurs. At each wavelength between light and dark boundary region detection by image analysis. At each wavelength, dependency between light and dark boundary region and refractive-index of process liquid measurement is detected, the Abbe number by refractive-index values obtained from: V D = n D - 1 n F - n C ; nD=refractive-index of process liquid to measure at 589.3 nm; nF=refractive-index at 486.

Abstract: A method and arrangement are disclosed for measuring a flow rate of optically non-homogeneous material in a process pipe. The non-homogeneous material can be illuminated through a window. Images are taken with a camera, through a window, of illuminated non-homogeneous material. Correlation between temporally successive images determines travel performed by the non-homogeneous material in the process pipe between capture of temporally successive images. Velocity of the non-homogeneous material is determined by the time difference between the successive images and the travel.

Abstract: An exemplary arrangement includes a prism-shaped measuring window, which has a measuring surface adapted to contact a substance being measured. A first surface is adapted to direct light originating from a light source to the measuring surface through the measuring window. A second surface is adapted to direct totally reflected light from an interface between the measuring surface in contact with the substance being measured and a substance being measured outside of the measuring window. A first lens arrangement is adapted to focus the light from the light source on the first surface. A second lens arrangement is adapted to focus the totally reflected light passing through the second surface to a device used for analysis. A lens in each of the first and second lens arrangements closest to the measuring window is integrated into the measuring window and establishes optical refractive power in the first and second surfaces.

Abstract: A measuring sensor includes an elongated shell part, manufactured from a synthetic gemstone material or ceramic material, is provided with a first end and a second end, the first end being arranged in a process medium to be measured. A housing structure is manufactured from a material softer than the synthetic gemstone material or the ceramic material and arranged to surround the measuring electronics. The second end of the elongated shell part is arranged to be supported against the housing structure. The elongated shell part is fastened to the housing structure by a connecting piece manufactured from a material having a hardness property between hardness properties of the material of manufacture of the elongated shell part and the material of manufacture of the housing structure.

Abstract: A method and an arrangement are disclosed in connection with a measurement arrangement of optical parameters of a separate sample taken from a process liquid, in which method a sample is taken from the process liquid. The sample can be arranged into a sample vessel provided with at least one measurement window, and optical parameters of the sample in the sample vessel are measured through the measurement window. In the sample in the sample vessel, a flow is produced which can be used to mitigate (e.g., prevent) the measurement window surface in contact with the sample from getting dirty. A back-and-forth flow can be produced in the sample residing in the sample vessel by means of pressure variation focused on the sample, and the back-and-forth flow can be focused on the surface of the optical measurement window.

Abstract: A method and measuring sensor are disclosed for measuring temperature, the method including arranging a measuring element of the sensor into thermal contact with a process liquid being measured, and directing a measuring signal received from the measuring element onward by measuring conductors connected to the measuring element. Close to the measuring element, terminal areas are established which are arranged in unrestricted thermal contact with the process liquid being measured, and the measuring conductors are connected to the measuring element through the terminal areas.

Abstract: The invention relates to a measuring sensor for measuring temperature in a chemical process, the measuring sensor comprising a measuring element supported on the frame of the measuring sensor and arranged in thermal contact with the process being measured, and measuring conductors connected to the measuring element for directing a measuring signal onward. The frame of the measuring sensor is made of mineral material.

Abstract: An exemplary method for measuring a refractive index of a substance being measured through an optical window, includes arranging the optical window in contact with the substance being measured, directing light to the interface of the optical window and substance being measured, where part of the light is absorbed by the substance being measured and part of it is reflected from the substance being measured to form an image, in which the location of the boundary of light and dark areas expresses a critical angle of the total reflection dependent on the refractive index of the substance being measured, and examining the formed image. Light is directed on a first structure and to desired angles on an interface between the optical window and substance being measured. Light reflected from the interface of the optical window and substance being measured is directed on a second structure.

Abstract: The invention relates to a method for in-line measuring the active KOH concentration in a KOH etching process in which process silicon hydroxide is produced by a reduction reaction according to the formula: 2K+ (aq.)+2OH? (aq.)+2H2O+Si?2K+ (aq.)+H2SiO42? (aq.)+2H2 (g). The total concentration of KOH bath is measured by using a refractometer and the measurement result is corrected by the estimated K2H2SiO4 concentration.