Abstract: A method for measuring boron concentration and an apparatus for performing the method are provided. The boron concentration measuring apparatus includes a reaction unit, an injection unit, a power supply unit, an electric current meter, a pH measuring device and an analysis unit to calculate the boron concentration with high reliability by calculating a mole concentration of boron ions through the analysis unit through calculating the titration time and the current amount during the titration time.

Abstract: An L-shaped toothbrush comprises a head having a top surface and a bottom surface, a horizontal length of the head being larger than a vertical length of the head, a lower brush formed in a direction perpendicular to the bottom surface of the head, a handle connected to a side surface of a middle portion of the head, bent in an L shape, and extending from the head, the handle integrally formed with the bead, and an upper brush formed on the top surface of the head.

Abstract: An L-shaped toothbrush comprises a head having a top surface and a bottom surface, a horizontal length of the head being larger than a vertical length of the head, a lower brush formed in a direction perpendicular to the bottom surface of the head, a handle connected to a side surface of a middle portion of the head, bent in an L shape, and extending from the head, the handle integrally formed with the bead, and an upper brush formed on the top surface of the head.

Abstract: The disclosure relates to an anode material for a sodium-ion battery having the general formula AOx—C or ACx—C, where A is aluminum (Al), magnesium (Mg), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), zirconium (Zr), molybdenum (Mo), tungsten (W), niobium (Nb), tantalum (Ta), silicon (Si), or any combinations thereof. The anode material also contains an electrochemically active nanoparticles within the matrix. The nanoparticle may react with sodium ion (Na+) when placed in the anode of a sodium-ion battery. In more specific embodiments, the anode material may have the general formula MySb-M?Ox—C, Sb-MOx—C, MySn-M?Cx—C, or Sn-MCx—C. The disclosure also relates to rechargeable sodium-ion batteries containing these materials and methods of making these materials.

Abstract: The disclosure relates to an anode material for a sodium-ion battery having the general formula AOx—C or ACx—C, where A is aluminum (Al), magnesium (Mg), titanium (Ti), vanadium (V), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), zirconium (Zr), molybdenum (Mo), tungsten (W), niobium (Nb), tantalum (Ta), silicon (Si), or any combinations thereof. The anode material also contains an electrochemically active nanoparticles within the matrix. The nanoparticle may react with sodium ion (Na+) when placed in the anode of a sodium-ion battery. In more specific embodiments, the anode material may have the general formula MySb-M?Ox—C, Sb-MOx—C, MySn-M?Cx—C, or Sn-MCx—C. The disclosure also relates to rechargeable sodium-ion batteries containing these materials and methods of making these materials.

Abstract: An electron gun for a color cathode ray tube having a cathode, a control electrode and a screen electrode together constituting of a triode, and a main lens for focusing and accelerating an electron beam formed by the triode. The electron gun is characterized by a horizontally elongated electron beam passing hole formed in the control electrode having its long axis disposed in the arrangement direction of the electron beam passing hole. A horizontally elongated slot encompassing the electron beam passing hole having its long axis disposed in the arrangement direction of the electron beam passing hole is formed in the screen electrode opposed to the control electrode, thereby preventing the focusing characteristics of the electron beam from being reduced throughout the surface of the fluorescent layer by the influence of the deflection yoke.

Abstract: In a dynamic focus electron gun, a horizontal dynamic focus voltage is varied according to those portions of a screen where the electron beam arrives and is applied so that the peak-to-peak amplitude of the horizontal dynamic focus voltage in one horizontal deflection period for the upper and lower portions of the screen is greater than that for the screen's center, thereby accomplishing uniform beam spots throughout the screen.