Question 1

In an online slurry analysis system, how do I know if the recirculating load is being fully monitored?

Accepted Answer

To fully monitor the recirculating load, it is also necessary to monitor the rougher and scavenger concentrates and cleaner tailing streams. As recirculating loads tend to build up slowly with time, these analyses are not required on a minute-by-minute basis so these streams can be monitored with a lower cost-per-stream centralized analyzer.

Question 2

In an online elemental analysis system, how critical is a given stream is in the overall process control strategy?

Accepted Answer

If the critical streams are monitored frequently as per the recommended criteria, the operators should be able to control the plant to give overall stability and best metallurgical results at minimum cost. The less critical intermediate streams can then be monitored at a lower frequency for the fine tuning of the circuit.

The degree of confidence required in the assay-based control decisions must be known. Streams that are more critical for control of the plant need to be monitored more frequently. Trends in plant performance will then be shown in more detail, showing effect of control actions on grade in real-time and giving greater confidence in control decisions. For example, in a base metal concentrator, the main objective might be to minimize metal losses in primary floatation while producing a particular concentrate grade in the cleaners. In addition, test work may show that recirculating loads tend to build up in the cleaning stages which is a result of recovery of excessive gangue in the rougher concentrate. Continuous analysis of tailings grades provides a critical tool in the operation of rougher flotation. On-line analysis of concentrates provides a tool to manage grade-recovery in the cleaners and better control impurities to meet the smelter requirements.

Question 3

In an online elemental analysis system, do the elements to be analyzed and the frequency of analysis need to be specified for each process stream?

Accepted Answer

The elements to be analyzed are determined by the objectives of the process control strategy and the particular metallurgical problems which are anticipated from prior metallurgical test work. The frequency of analysis required, often referred to as the assay update time, depends on the following criteria:

- The fluctuation in assays in a given process stream considering the residence times of the processes immediately upstream
- The stability of the circuit
- At a minimum, the assay update times of the analyzers for the critical streams should be less than half of the retention time of the preceding process stage

Therefore, in the tailings stream from a scavenger bank of cells with a retention time of 5 mins, the grade can be expected to vary considerably in 2 mins during upset conditions or reactions to process control actions so on-line analysis should be made at an interval less than this to provide the best visibility of real-time plant performance. To obtain these sorts of assay update times, one requires dedicated analyzers or a centralized analyzer with just a few streams located nearby the process sample points.

Question 4

What capital constraints should be considered when selecting an online slurry analysis system?

Accepted Answer

When selecting the right online slurry analysis system, there are several capital constraints that should be considered, including

- Capital investment,
- Economic benefits expected
- Cost of on-going maintenance
- Flexibility of system modules
- Incremental benefits of less essential assays.

The economic benefits of having an on-line slurry analysis system coupled to a control system, be it manual or fully automatic, comes from one or more of the following: increase in metal recovery, improvement in concentrate grade and control of impurities, reduction in reagent consumption, decrease in operating costs, and improvement in stability of the operation.

These benefits have to be weighed against the capital investment of the analysis system and the cost of on-going maintenance including mechanical repairs, sample pump servicing or replacement, sample transport system troubleshooting, electronic repairs, analyzer downtime and calibration. The flexibility of hybrid systems of dedicated analyzers for the critical streams and multi-stream analyzers for the less critical streams enables the most cost effective analysis system to be selected for each particular plant. In working out what streams are to be measured, a cost benefit analysis should be carried out to guide the decision making process.

Question 5

What is the standard warranty of the Qubit 4 Fluorometer, with WiFi?

Accepted Answer

3 years is the standard warranty period.

Find additional tips, troubleshooting help, and resources within our Nucleic Acid Quantification Support Center.

Question 6

I would like to use my Qubit 4 Fluorometer with the Qubit 1X dsDNA BR Assay, but the assay is not listed as an option on the fluorometer. How can I resolve this?

Accepted Answer

The Qubit 4 Fluorometer needs to be updated. The Qubit 4 Fluorometer can be updated with the USB that was provided with the Qubit. If you do not have the USB, we recommend using an empty 2.0GB that is FAT32 formatted. If the USB is not recognized, leave USB plugged in for a few minutes before running the update. This should give you the assay you need to run the Qubit Assay.

You can find the updates on the Technical Resources for Qubit Fluorometers page.

Question 7

My Qubit 4 Fluorometer, with Wifi (Cat. No. Q33238) has not installed the files to allow me to use the Qubit ssDNA Assay Kit. Could you provide the files I need?

Accepted Answer

To access the Qubit ssDNA Assay Kit on the Qubit 4, please try selecting the Oligo option from the home screen, and the ssDNA Assay should appear there. If not, please check if you need to update your instrument firmware to the latest version v2.19, which is available for download from the Technical Resources for Qubit Fluorometers page on thermofisher.com.
For standard/preloaded Qubit assays we do not provide individual .qbt files, but they are included in the firmware itself.

Question 8

How can I use the Qubit Protein Broad Range Assay (Cat. No. A50668) on the Qubit 4 Fluorometer, with WiFi (Cat. No. Q33238)?

Accepted Answer

To be able to use the Qubit Protein Broad Range Assay (Cat. No. A50668) on the Qubit 4 Fluorometer (Cat. No Q33238) you would need to install the latest firmware on the fluorometer. Please find the latest Qubit 4 firmware (v2.19) on the following webpage: https://downloads.thermofisher.com/Qubit4/v2.19/Qubit4_update_v2.19.pak Save the firmware update on a USB stick and upload it to the Qubit 4 Fluorometer. Once the firmware update has been installed, you will be able to see the Protein BR assay on the Qubit 4 Fluorometer.

Find additional tips, troubleshooting help, and resources within our Protein Assays and Quantitation Support Center.

Question 9

How can I access user settings when using the Qubit 4 Fluorometer, with WiFi (Cat. No. Q33238)?

Accepted Answer

You have to create a user profile and log in. Please follow the instructions for login below:

Turn on the device
From the home screen, touch the person icon on the top left corner
Touch the “Get Started” button
Touch the “Create Profile” button
information for username and pin
Log in by touching the person icon and entering the user info in the sign in fields

Find additional tips, troubleshooting help, and resources within our Nucleic Acid Quantification Support Center.

Question 10

I want to perform a system verification on my Qubit 4 Fluorometer, with WiFi (Cat. No. Q33238). However, under "Settings", the System Verification is inactive. How should I proceed?

Accepted Answer

Due to cybersecurity regulations, it is mandatory to create a profile on the device before all features become available. Please follow these steps:

release notes.

Nucleic Acid Quantification Support Center

Question 11

Which Qubit Fluorometers allow the designing of custom assays?

Accepted Answer

Custom assays can be designed on Qubit 3 and Qubit 4 Fluorometers. For more information, please see the following link.

Find additional tips, troubleshooting help, and resources within our Nucleic Acid Quantification Support Center

Question 12

I am trying to update the software on my Qubit 4 Fluorometer, with WiFi (Cat. No. Q33238). However, this option appears to be inactive. What should I do?

Accepted Answer

Due to the security settings of the Qubit 4 Fluorometer, with WiFi (Cat. No. Q33238), you will need to be logged in as a user to access the full settings menu. When not logged in as a user, options such as instrument settings, software update and system verification remain inactive.

Find additional tips, troubleshooting help, and resources within our Nucleic Acid Quantification Support Center

You can find instructions on how to set up a user profile on the Qubit 4 Fluorometer on page 2 of the Firmware release notes.

常见问题