Abstract: The present technology provides a semiconductor laser capable of suppressing a decrease in yield while suppressing an influence on laser characteristics. The semiconductor laser according to the present technology includes a resonator having a multilayer structure including: a first cladding layer; a second cladding layer; and an active layer disposed between the first cladding layer and the second cladding layer, the multilayer structure including a pair of resonator end surfaces facing each other. The resonator has a ridge structure extending in a resonator length direction on a surface on a second cladding layer side. A plurality of grooves is provided in at least one of one side portion or the other side portion sandwiching the ridge structure in plan view on the surface of the resonator on the second cladding layer side.

Abstract: A synthetic adsorbent, where a maximum value of a differential pore volume under a pressure condition of 0.5 to 30.0 psia is greater than 0.05 mL/g. A method of measuring the differential pore volume includes reducing a pressure in a sample container where the synthetic adsorbent that has been dried is placed to 10 Pa or less, mercury is degassed by reducing the pressure to 10 Pa or less, and the sample container is filled with the mercury at a pressure of 0.5 psia, measuring a mercury intrusion amount when the pressure in the sample container filled with the mercury is increased from 0.5 to 30.0 psia, and calculating the differential pore volume by dividing an amount of an increase in the mercury intrusion amount when a first-stage pressure calculated based on the mercury intrusion amount measured in the measuring is increased, by a measured amount of the synthetic adsorbent.

Abstract: An object of the present invention is to provide a method for purifying a protein capable of significantly reducing amount of impurities and achieving a high recovery rate, compared to a method for purifying a protein using an activated carbon of the related art. The present invention relates to a method for purifying a protein using an activated carbon, including: bringing an activated carbon pretreatment solution obtained by adjusting conductivity of a protein-containing aqueous solution into contact with an activated carbon; separating the protein and impurities in a non-adsorption mode to obtain the protein of interest with a low content of impurities.