Privacy Policy

Last updated: August 25, 2026

MUXU LAB (“we”, “us”) cares about the privacy of our visitors. This policy explains what information we may process when you visit this website, read our experiment guides, or contact us, and how you can manage that information.

1. Information we may collect

When you contact us by email, we receive the name, role, email address and message contents you choose to provide. The email form on the Contact page sends through your local email client and saves nothing to our servers.

The reader message board on that same page does store what you submit in this site’s database (Cloudflare D1, hosted in the Asia-Pacific region): the display name you enter, your role (student / parent / teacher / other), the subject, the message text, the language version and the submission time. Once a person has reviewed and approved it, that content is displayed publicly on the board — so please post only what you are happy to make public, and never real names, schools or classes, home addresses, phone numbers or social accounts. The board collects no email address and requires no account. To prevent flooding we also store a salted hash of your IP address; it is used only to count how many messages came from one source in 24 hours, cannot be turned back into an IP address, and is cleared after 30 days. Messages that are not approved are never shown publicly, and we may refuse or remove any message at any time.

The web server, or analytics tools we may add in the future, may automatically log basic visit data such as the time of access, browser type, device type, referring page, and approximate region. This data is used mainly to keep the site secure, analyze overall traffic trends, and improve the reading experience.

2. How we use information

To reply to your messages and handle topic suggestions and content corrections;
To review and publicly display messages on the reader board, and to plan which experiments we write about next;
To keep the site secure, troubleshoot problems, and improve the visiting experience;
To understand which experiment guides are most helpful, so we can improve our topics and pages;
To meet necessary obligations where required by applicable laws and regulations.

We do not sell your personal information, and we do not disclose personally identifiable information to third parties unrelated to your correspondence, except where laws or regulations require otherwise.

3. Cookies, analytics and advertising

This site uses Google AdSense to serve ads. To display ads, third-party vendors including Google and its partners may set or read cookies on your device, use web beacons, and record identifiers such as your IP address, in order to serve, measure and optimize ads based on your visits to this and other websites. For how Google uses this data, see Google’s Privacy Policy and policies.google.com/technologies/ads.

You can manage or turn off personalized advertising in Google’s ad settings (myadcenter.google.com), and you can restrict or clear cookies in your browser settings. For visitors from the European Economic Area, the United Kingdom and Switzerland, where applicable we will ask for your consent to the use of cookies through a consent management tool.

4. Minors

This site is a teaching reference for middle school science teachers and parents of middle school students; its content is meant for adult readers preparing lessons or guiding children at home, and it is not designed for unsupervised browsing by minors. We do not actively collect personal information unrelated to experiment teaching, and no account registration or identity details are required to read any of our content. If a minor writes to us on their own, we suggest a parent or teacher be informed first; if you believe a child has provided us with unnecessary personal information, contact us at the email address below and we will delete it. The reader message board on the Contact page does let students post, and "Student" is one of the role options — that field is optional, the board asks for no email address and no account, the page explicitly tells posters to leave out real names, schools, classes and contact details, and every message is reviewed by a person before it is published.

About advertising: ads on this site are served by Google AdSense, and whether personalized ads appear depends on Google’s serving settings and your own choices. You or your parents can turn off personalized ads at any time at myadcenter.google.com; ads will still appear afterwards, but they will no longer be targeted by browsing interests. If you believe an ad shown on this site is inappropriate for minors, please send the page link to the email address below and we will verify it and report it to Google.

5. Your controls over ads and data

Personalized ads switch: turn personalized advertising on or off at any time in Google’s ad settings (myadcenter.google.com).
Visitors from the EEA, UK and Switzerland: where applicable, we ask for your consent to cookies and personalized ads through a Google-certified consent management tool, and you can change your choice at any time.
Universal opt-out signals: for visitors covered by applicable U.S. state privacy laws (such as those of California, Colorado, Connecticut, Delaware and Oregon), if your browser sends a universal opt-out signal such as Global Privacy Control (GPC), Google enables restricted data processing for the corresponding requests and will not use your personal information for cross-site targeted advertising.
At the browser level: you can restrict or clear cookies in your browser settings, or visit this site in private browsing mode.

6. Retention and security

We keep information only as long as reasonably needed for the purposes above, and we take reasonable measures to prevent unauthorized access, disclosure, alteration or loss. No transmission over the internet is absolutely secure, so please do not send passwords, ID numbers or other highly sensitive information by ordinary email.

For the message board specifically: approved messages stay published until you or we delete them; messages that were not approved are cleared periodically; the IP hash used for rate limiting is kept no longer than 30 days. The moderation dashboard is accessible only to the site owner.

7. Third-party links

This site may contain links to other websites. Third-party sites have their own privacy practices, which we cannot control; we recommend reading their policies before visiting.

8. Your choices and rights

If you would like to access, correct or delete information you have voluntarily provided to us, or if you have questions about this policy, contact us at chunli.sun@tjmuxu.com. We will respond within a reasonable time after verification. To have one of your published board messages removed, email that same address with the display name you used and roughly what the message said — we will delete it, and no proof of identity is required.

9. Updates to this policy

We may update this policy as our services change or as compliance requires. New versions will be published on this page with a new “last updated” date.