431 results about "PH indicator" patented technology

A wetness indicator composition contains (a) 0.1% to 5% by weight of a pH indicator that is substantially colorless at pH 7 and develops a color in an acidic environment, (b) 20% to 90% by weight of a surfactant, (c) 5% to 55% by weight of a polyalkylene glycol, (d) 0% to 70% by weight of a polymer having a carboxyl group, and (e) 0.1% to 5% by weight of an acidic substance other than components (b) and (d). In an absorbent article including a topsheet 2, a backsheet 3, and an absorbent member 4 interposed between the topsheet 2 and the backsheet 3 and having applied thereon a hot-melt composition that changes color on contact with a body fluid, the wetness indicator composition is used as the hot melt composition.

The invention discloses a method and a device for detecting the freshness of fish based on olfaction visualization, which is characterized in that a computer is connected with a constant temperature control room and a scanner; a visual gas sensor array, the scanner, a reaction room and a sample room are arranged inside the constant temperature control room; detected gas diffused from a detected fish sample is in contact with the visual gas sensor array; the detected gas reacts with a porphyrins sensor, a pH indicator sensor or a solvation chromotropic dye sensor arranged in the visual gas sensor array; images before and after the reaction are collected by the scanner and input into the computer; and the freshness of the detected fish sample is determined according to the correlation between the color change of the three sensors and the variety and the concentration of the detected gas. The invention can ensure that the extraction quantity of characteristic values is reduced by determining the selection of the sensor type and the characteristic values; the synthesis course is simple, and the use quantity of the sensors is less; the gas can be fully contact with the sensors; the detection by human eyes can be utilized; and the use of the device is simple and convenient; the detection time only needs 3 to 5 minutes.

Improved carbon dioxide sensors are disclosed which are less sensitive to the moisture content of the environment and which are substantially insensitive to oxygen levels under normal working conditions. The CO₂ sensor comprises a pH indicator and long-lived reference luminophore and a porous sol-gel matrix. Combined CO₂ and O₂sensors are also described. Further disclose are methods of printing sensor onto substrates.

The invention relates to the culture medium research and development technical field of modern biological technology and provides a serum-free medium for MDCK cell large-scale adherent culture and single-cell suspension culture, which comprises 21 amino acids, 6 vitamins, 8 salts, 8 lipids, 4 trace elements, 2 buffers, 1 protein hydrolysate, 1 acid-base indicator and 6 other additives. The serum-free medium can be prepared by the conventional preparation method, and an application method thereof is the conventional method. The serum-free medium has the beneficial effects that: the serum-free medium does not contain serum, has clear components, is beneficial for separating and purifying the product and improves the product quality; the serum-free medium supports long-term subculture of MDCK cells and does not require long-term and complex adaptation process; and the serum-free medium can well support the adherent growth and single-cell suspension growth of the MDCK cells, has clear components and easy preparation and utilization, and is suitable for mass production of biological products.

The invention relates to an animal origin-free low-protein culture medium suitable for animal cell product production, comprising 24 basic metabolism nutrients, 11 vitamins, 3 transferrin substitute compounds, 5 lipid compounds, 2 nucleic acid compounds, 4 hormones and growth factors, 3 antioxidants, 1 shear-resistant protective agent, 1 pH indicator, 2 pH buffers, 9 other inorganic salts, soy hydrolysates adopted to substitute animal origin component, and composition of ferrous sulfate, ferric nitrate and EDTA-2Na adopted to substitute transferrin. The culture medium can be made by dissolving the aforementioned components in triply distilled water. The positive effects of the culture medium are as follows: the culture medium contains no animal origin component, the total protein content is lower than 10mg/L, which helps separate and purify products and is suitable for production of recombinant protein medicaments; the culture medium supports normal growth and long-term subculturing of animal cells; the culture medium can be used without adaptation, is easily prepared and is suitable for massive production of animal cell products.

The invention relates to a bicarbonate-containing medical solution package. The package comprises a gas-permeable plastic container holding a bicarbonate-containing medical solution and a gas-impermeable plastic packaging member containing the gas-permeable plastic container. A carbon-dioxide atmosphere is established in the space between the container and packaging member. In addition, a pH indicating device is contained within the space between the container and packaging member. The pH indicating device is a gas-permeable plastic packet containing a bicarbonate-containing fluid (similar to the medical solution) and a pH indicator. The pH indicator undergoes a change in color in response to a change in pH of the fluid. Use of this package allows the easy monitoring of a change in pH and consequent aging of the medical solution due to prolonged storage or damage to the outer packaging member.

An isolation plating medium for the identification of Salmonella bacteria in a sample containing a plurality of different bacteria comprising a mixture of a carbohydrate capable of being a metabolic source for Salmonella bacteria and supporting colonies of Salmonella bacteria, a pH indicator dye that changes the color of the plating medium to a first color different from the color of the medium responsive to a change in the pH of the medium, a first substrate that does not react with Salmonella bacteria and injects color into the medium of a second color responsive to the presence of beta-galactosidase, the second color contrasting with the first color and the color of the medium, a second substrate that does not react with Salmonella bacteria and injects color into the medium of substantially the same color as the second color responsive to the presence of beta=galactosidase, and an ingredient for thickening the mixture in sufficient quantity to solidify the mixture.

A system and method diagnoses esophageal reflux in a patient. A catheter includes a first pressure sensor configured to measure intra-abdominal pressure when the catheter is inserted into the stomach of a patient. A second pressure sensor is located proximal to the distal tip and configured to measure intra-thoracic pressure. A pH indicator is carried by the catheter body and configured to indicate that reflux has occurred in response to an involuntary reflex cough test. A processing device is configured to receive data regarding the first and second pressure sensors and regarding the pH indicator and process that data and assess if reflux is present during the involuntary epoch.

The present invention provides chemical compounds (compositions of matter) and methods useful for determining pH and/or pH change in an environment. Specific compounds of the invention include at least five fused molecular rings.

A method for preparing color-sensitive gas transducer array includes using hydrophobic prophyrin class compound and acid-base indicator as gas color-sensitive material, dissolving said color-sensitive material in organic solvent, using white Teflon material as base material of said transducer and processing Teflon material to be square block, making labels in certain size on square block, coating a layer hydrophobic white stabilizer on each label, fixing certain amount of gas color-sensitive solution on stabilizer at label of base, fixing one type of said solution on each label and obtaining said transducer array after organic solvent is dried.

Particular aspects provide novel devices and methods for accurately measuring total ammonia (NH₃ plus NH₄⁺) in a solution (e.g., freshwater and saltwater) by spatially proximate, simultaneous and continuous quantitative measurement of solution pH and ammonia. The devices overcome prior art inaccuracies relating to non-homogeneous sampling, and to spatial, temporal and thermal sampling discontinuities. Particular embodiments provide a combination pH and ammonia measuring device, comprising: a submersible member; a submersible non-bleeding ammonia-sensing portion attached to the submersible member and suitable to provide for a continuous visual indicator of solution ammonia concentration; a submersible non-bleeding pH-sensing portion attached to the submersible member and suitable to provide for a continuous visual indicator of solution pH; visual ammonia and pH indicator comparison means suitable for comparative quantitative determination of solution ammonia concentration and pH. Additional aspects provide novel ultra-sensitive devices and methods using same for measuring ammonia in air or solution.

The invention is concerned with the manufacture method of the ditch groove power semiconductor device. It is: provides the materials of the basal; forms the first electric transmit epitaxy layer on the basal; forms the second electric transmit zone and the ditch groove inside the epitaxy layer; forms the ebb first electric transmit area and the medium layer with the ditch groove; and then, forms the electric transmit area within the medium layer; forms the first electric transmit source area on the surface of the second electric transmit area; forms the second electric transmit contact area with higher doping PH indicator on the second electric transmit zone surface; forms the passivation layer cap on the top of the ditch groove which must with the medium layer and the electric transmit area; forms the diffusion protecting layer on the surface of the source area and the contact area; finally, forms the structure surface with good electric connection. The invention can control the threshold voltage of the device and improves the breakdown strength of the oxide layer of the device bottom area, and improves its electric connection reliability with no extra cover film printing plate and complex method request.

The invention describes uses of various acid-base indicators in combination with consumer products, such as herbicides, where upon application the surface treated is visualized by color and then, with time, the color disappears.

An improved color changing correction fluid is provided which includes either a volatile base or a volatile acid in combination with a color changing pH indicator, all in a water based fluid or system. As the fluid dries, the volatile base or acid evaporates along with the water and the pH color changing indicator changes from a colored state to a clear state. For white paper, a white pigment is utilized and therefore the fluid changes from a colored state to a white finished state as the solvent water and acid or base evaporates. Different color pigments can be utilized to match the color of the particular paper or substrate.