Abstract: A cement composition containing a fluid loss control agent and a cement, wherein the fluid loss control agent contains a vinyl alcohol polymer and a crosslinking agent, and a swelling percentage of the fluid loss control agent is 200% or more and 3,600% or less.

Abstract: Disclosed are compositions and kits of fibers and acid-functional vinyl alcohol polymers, wherein such compositions and kits are useful for wellbore remediation as applied to a subterranean formation traversed by the borehole of an oil or gas well.

Abstract: A housing (20) has a passage port (3) that serves as both the outlet for the illumination light (IL) to go out of the housing (20) toward a sample surface (S) and the inlet for the reflection light (RL) reflected on the sample surface (S) to enter the housing (20). A transparent member (19) is disposed at the passage port (3) to prevent dust including paper dust from entering the housing (20). A light quantity calculation unit (71) calculates the light quantity of light received by a light reception lens (33). A notification unit (81) performs a predetermined notification when the light quantity is less than or equal to a predetermined value.

Abstract: A reflection characteristic measurement system includes: a hand-held reflection characteristic measurement apparatus including a light receiver that receives reflected light; and a guide member that supports the reflection characteristic measurement apparatus, wherein the guide member includes: a plate-shaped support part having a support surface to support the reflection characteristic measurement apparatus; and a white calibration plate applicable to white calibration of the reflection characteristic measurement apparatus, the support part includes: an elongated hole extending in one direction along the support surface; and a guide structure provided to guide the reflection characteristic measurement apparatus so as to enable the apparatus to move along the one direction, the light receiver is provided on the reflection characteristic measurement apparatus so as to move along a predetermined moving path, the moving path of the light receiver extends in the one direction, and the white calibration plate is p

Abstract: A housing (20) has a passage port (3) that serves as both the outlet for the illumination light (IL) to go out of the housing (20) toward a sample surface (S) and the inlet for the reflection light (RL) reflected on the sample surface (S) to enter the housing (20). A transparent member (19) is disposed at the passage port (3) to prevent dust including paper dust from entering the housing (20). A light quantity calculation unit (71) calculates the light quantity of light received by a light reception lens (33). A notification unit (81) performs a predetermined notification when the light quantity is less than or equal to a predetermined value.

Abstract: A reflection characteristic measurement system includes: a hand-held reflection characteristic measurement apparatus including a light receiver that receives reflected light; and a guide member that supports the reflection characteristic measurement apparatus, wherein the guide member includes: a plate-shaped support part having a support surface to support the reflection characteristic measurement apparatus; and a white calibration plate applicable to white calibration of the reflection characteristic measurement apparatus, the support part includes: an elongated hole extending in one direction along the support surface; and a guide structure provided to guide the reflection characteristic measurement apparatus so as to enable the apparatus to move along the one direction, the light receiver is provided on the reflection characteristic measurement apparatus so as to move along a predetermined moving path, the moving path of the light receiver extends in the one direction, and the white calibration plate is p

Abstract: A drive device and a lens unit include a base member; a driven member disposed at a prescribed distance from the base member and having a flat plane; a support member coupling the base member and the driven member and supporting the driven member so as to substantially maintain a prescribed distance between the base member and the driven member from start to end of movement of the driven member; and a driving member driving the driven member so as to move the flat plane in parallel from start to end of movement. The driving member causes a linear shape-memory alloy wire to expand and contract, thereby moving the driven member.