Abstract: The present disclosure provides a color chart and a test kit for estimating chemical oxygen demand of water. The color chart includes a blue component, an indigo component, an umber component, and an orange component. The test kit includes an oxidant, a reductant, an indicator, and the color chart. The present disclosure also provides a method for estimating chemical oxygen demand of water. The method includes providing a water sample; adding an oxidant to the water sample; heating the water sample; adding a reductant to the water sample; adding an indicator to the water sample, such that the water sample develops a color; and matching the color of the water sample with the color components of the color chart to estimate the chemical oxygen demand of the water sample.

Abstract: The present disclosure provides a color chart and a test kit for estimating chemical oxygen demand of water. The color chart includes a blue component, an indigo component, an umber component, and an orange component. The test kit includes an oxidant, a reductant, an indicator, and the color chart. The present disclosure also provides a method for estimating chemical oxygen demand of water. The method includes providing a water sample; adding an oxidant to the water sample; heating the water sample; adding a reductant to the water sample; adding an indicator to the water sample, such that the water sample develops a color; and matching the color of the water sample with the color components of the color chart to estimate the chemical oxygen demand of the water sample.

Abstract: The present disclosure provides a color chart and a test kit for estimating chemical oxygen demand of water. The color chart includes a blue component, an indigo component, an umber component, and an orange component. The test kit includes an oxidant, a reductant, an indicator, and the color chart. The present disclosure also provides a method for estimating chemical oxygen demand of water. The method includes providing a water sample; adding an oxidant to the water sample; heating the water sample; adding a reductant to the water sample; adding an indicator to the water sample, such that the water sample develops a color; and matching the color of the water sample with the color components of the color chart to estimate the chemical oxygen demand of the water sample.

Abstract: The present disclosure provides a color chart and a test kit for estimating chemical oxygen demand of water. The color chart includes a blue component, an indigo component, an umber component, and an orange component. The test kit includes an oxidant, a reductant, an indicator, and the color chart. The present disclosure also provides a method for estimating chemical oxygen demand of water. The method includes providing a water sample; adding an oxidant to the water sample; heating the water sample; adding a reductant to the water sample; adding an indicator to the water sample, such that the water sample develops a color; and matching the color of the water sample with the color components of the color chart to estimate the chemical oxygen demand of the water sample.

Abstract: A process of producing a titanium dioxide-based photocatalyst used for degradation of organic pollutants includes the steps of: (a) preparing a mixture solution which includes a titanium dioxide precursor and a transition metal salt having a transition metal ion which is capable of reducing a band gap of titanium dioxide; (b) aging the mixture solution so as to obtain a gel; (c) treating the gel to form an ion-doped titanium dioxide; (d) depositing silver nanoparticles on the ion-doped titanium dioxide to obtain a modified titanium dioxide-based photocatalyst; and (e) calcining the modified titanium dioxide-based photocatalyst.

Abstract: A device for detections of one or more analytes in one or more samples is disclosed. The device can simultaneously detect multiple analytes in a sample or an analyte in a plurality of samples. The device has a plurality of wells formed thereon. Each of the well has a respective composition loaded therein, wherein each of the composition comprising a respective catalyst is encapsulated in sol-gel. In addition, a first fluorescent dye and a second fluorescent dye are encapsulated in the sol-gel or added to the sample(s) for detection and quantitation. The catalyst(s) interacts with or reacts with the specific analyte(s) in the sample(s) and causes a change(s) in spectroscopic property. The concentration of an analyte(s) is detected by comparing the normalized spectroscopic property to a standard curve. A method is also disclosed for the detection of one or more analytes in one or more samples by using the device.