PH Responsive glass compositions and electrodes

Claim 2

A glass composition for use in pH responsive glass electrodes consisting essentially of: ______________________________________ Component Mole % ______________________________________ Li.sub.2 O 30-40 SiO.sub.2 50-60 La.sub.2 O.sub.3 2-8 Ta.sub.2 O.sub.5 2-8 Cs.sub.2 O 0-3 wherein Li.sub.2 O+Ta.sub.2 O.sub.5 > -34 ______________________________________

Claim 3

The glass composition of claim 1 consisting essentially of: ______________________________________ Component Mole % ______________________________________ Li.sub.2 O 32-36 SiO.sub.2 55-59 La.sub.2 O.sub.3 4-7 Ta.sub.2 O.sub.5 4-7 ______________________________________

Claim 4

The glass composition of claim 1 which contains at least 1 mole % Cs 2 O.

Claim 5

In a glass electrode for pH and potentiometric measurements, the improvement wherein the glass sensing membrane of said electrode has a composition of claim 1.

Claim 6

In a glass electrode for pH and potentiometric measurements, the improvement wherein the glass sensing membrane of said electrode has a composition of claim 2.

Claim 7

In the process for measuring the pH of an aqueous solution, wherein a glass electrode is contacted with said solution and the resulting potentiometric response is a measure of the hydrogen ion concentration of said solution, the improvement wherein said glass electrode is the electrode of claim 4.

Claim 8

In the process for measuring the pH of an aqueous solution which process includes the steps of providing an electrode with a pH responsive glass sensing membrane, immersing said sensing membrane and a standard reference electrode in said solution while said glass electrode and said reference electrode are electrically connected to a potentiometer, the improvement wherein said ion selective glass sensing membrane has a composition of claim 5.

Claim 9

In the process for measuring the pH of an aqueous solution which process includes the steps of providing an electrode with a pH responsive glass sensing membrane, immersing said sensing membrane and a standard reference electrode in said solution while said glass electrode and said reference electrode are electrically connected to a potentiometer, the improvement wherein said ion selective glass sensing membrane has a composition of claim 4.

Claim 10

The glass composition of claim 1 consisting essentially of: ______________________________________ Component Mole % ______________________________________ Li.sub.2 O 30 SiO.sub.2 60 La.sub.2 O.sub.3 4 Ta.sub.2 O.sub.5 6 ______________________________________

Claim 11

The glass composition of claim 1 consisting essentially of: ______________________________________ Component Mole % ______________________________________ Li.sub.2 O 30 SiO.sub.2 59 La.sub.2 O.sub.3 6 Ta.sub.2 O.sub.3 4 Cs.sub.2 O 1 ______________________________________

Claim 12

The glass composition of claim 1 consisting essentially of: ______________________________________ Component Mole % ______________________________________ Li.sub.2 O 34 SiO.sub.2 55 La.sub.2 O.sub.3 8 Ta.sub.2 O.sub.5 2 Cs.sub.2 O 1 ______________________________________

Claim 13

The glass composition of claim 1 consisting essentially of: ______________________________________ Component Mole % ______________________________________ Li.sub.2 O 34 SiO.sub.2 55 La.sub.2 O.sub.3 2 Ta.sub.2 O.sub.5 8 Cs.sub.2 O 1 ______________________________________

Claim 14

The glass composition of claim 1 consisting essentially of: ______________________________________ Component Mole % ______________________________________ Li.sub.2 O 40 SiO.sub.2 50 La.sub.2 O.sub.3 5 Ta.sub.2 O.sub.5 4 Cs.sub.2 O 1 ______________________________________

Claim 15

The glass composition of claim 1 consisting essentially of: ______________________________________ Component Mole % ______________________________________ Li.sub.2 O 32-36 SiO.sub.2 55-59 La.sub.2 O.sub.3 4-7 Ta.sub.2 O.sub.5 4-7 Cs.sub.2 O 0-3 ______________________________________

Claim 16

The glass composition of claim 14 consisting essentially of: ______________________________________ Component Mole % ______________________________________ Li.sub.2 O 34 SiO.sub.2 55 La.sub.2 O.sub.3 5 Ta.sub.2 O.sub.5 5 Cs.sub.2 O 1 ______________________________________

Claim 17

The glass composition of claim 14 consisting essentially of: ______________________________________ Component Mole % ______________________________________ Li.sub.2 O 33 SiO.sub.2 56 La.sub.2 O.sub.3 5 Ta.sub.2 O.sub.5 6 ______________________________________

Claim 18

The glass composition of claim 14 consisting essentially of ______________________________________ Component Mole % ______________________________________ Li.sub.2 O 32 SiO.sub.2 57 La.sub.2 O.sub.3 5 Ta.sub.2 O.sub.5 6 ______________________________________

Claim 19

The glass composition of claim 14 consisting essentially of: ______________________________________ Component Mole % ______________________________________ Li.sub.2 O 33 SiO.sub.2 56 La.sub.2 O.sub.3 4 Ta.sub.2 O.sub.5 7 ______________________________________

Claim 20

The glass composition of claim 14 consisting essentially of: ______________________________________ Component Mole % ______________________________________ Li.sub.2 O 34 SiO.sub.2 55 La.sub.2 O.sub.3 6 Ta.sub.2 O.sub.5 5 ______________________________________

Claim 21

The glass composition of claim 14 consisting essentially of: ______________________________________ Component Mole % ______________________________________ Li.sub.2 O 34 SiO.sub.2 55 La.sub.2 O.sub.3 5 Ta.sub.2 O.sub.5 6 ______________________________________

Claim 22

The glass composition of claim 14 consisting essentially of: ______________________________________ Component Mole % ______________________________________ Li.sub.2 O 34 SiO.sub.2 55 La.sub.2 O.sub.3 4 Ta.sub.2 O.sub.5 7 ______________________________________

Claim 23

The glass composition of claim 14 consisting essentially of: ______________________________________ Component Mole % ______________________________________ Li.sub.2 O 33 SiO.sub.2 56 La.sub.2 O.sub.3 6 Ta.sub.2 O.sub.5 4 Cs.sub.2 O 1 ______________________________________

Claim 24

The glass composition of claim 14 consisting essentially of: ______________________________________ Component Mole % ______________________________________ Li.sub.2 O 34 SiO.sub.2 55 La.sub.2 O.sub.3 3 Ta.sub.2 O.sub.5 5 Cs.sub.2 O 3 ______________________________________

Claim 25

The glass composition of claim 14, wherein said La 2 O 3 and said Ta 2 O 5 are present in said composition in approximately equal molar amounts.

Claim 26

The glass composition of claim 1, wherein said La 2 O 3 and said Ta 2 O 5 are present in said composition in approximately equal molar amounts.

Claim 27

A pH responsive glass membrane for use with electrodes for pH and potentiometric measurements, said glass membrane possessing a log volume resistivity at 25° C. within the range of about 8.3 and 9.5 ohm-centimeters, and having a composition consisting essentially of: ______________________________________ Component Mole % ______________________________________ Li.sub.2 O 30-40 SiO.sub.2 50-60 La.sub.2 O.sub.3 2-8 Ta.sub.2 O.sub.5 2-8 Cs.sub.2 O 0-3 Total Li.sub.2 O + Ta.sub.2 O.sub.5 ≧34 ______________________________________

Claim 28

A pH responsive glass membrane for use with electrodes for pH and potentiometric measurements, said glass membrane possessing a log volume resistivity at 25° C. within the range of about 8.3 and 9.5 ohm-centimeters, and having a composition consisting essentially of: ______________________________________ Component Mole % ______________________________________ Li.sub.2 O 30-40 SiO.sub.2 50-60 La.sub.2 O.sub.3 2-8 Ta.sub.2 O.sub.5 2-8 Cs.sub.2 O 0-3 Total Li.sub.2 O + Ta.sub.2 O.sub.5 ≧34 ______________________________________