What paid reading is
Every entry opens with a free preview — the process summary, ingredient ratios and the critical temperature or time windows. If the preview is enough, you pay nothing. To read the full text and download the PDF, you unlock that single entry: top up your USD wallet once, then spend per article. There is no subscription and no monthly fee.
What paid reading is
Every entry opens with a free preview — the process summary, ingredient ratios and the critical temperature or time windows. If the preview is enough, you pay nothing. To read the full text and download the PDF, you unlock that single entry: top up your USD wallet once, then spend per article. There is no subscription and no monthly fee.
What you get when you unlock
- Permanent access to the full article — return any time, no second charge.
- A watermarked PDF generated on demand, carrying your e-mail. Re-download it as often as you like from your own account.
- Personal licence only — see the licence terms below.
Membership and its validity
This site does not sell time-limited memberships, so there is nothing that "expires" on a calendar. What we use is a membership level earned by how much you have recharged in total:
- Account — stays open as long as it is in good standing. It is suspended and its balance forfeited only if you break the rules (shared credentials, bulk registration, scripted scraping).
- Membership level — set by your cumulative lifetime recharge. Reach a threshold and the level (and its discount) is yours permanently; it does not lapse.
- Wallet balance (USD) — has no expiry; it remains available until you spend it, as long as your account is active.
- Free daily quota — the free unlocks some levels grant reset every 24 hours and do not roll over. Unused free unlocks are not banked.
- Unlocked articles — once paid, accessible forever.
If you close your account, your balance and re-download ability end with it (see the Privacy Policy).
Licence and what you may not do
Payment grants a personal reading and private-download licence for your own account. You may not resell, sub-licence, publicly redistribute, or feed the material into a training dataset. Removing the watermark and republishing breaches the licence and may lead to account termination.
Eligibility, risk and safety
- You must be of legal age in your jurisdiction. By registering you confirm you are.
- All content is published for learning and reference. You assess safety and carry the risk. Where a procedure uses food, chemicals or preparations, run a small-scale trial first and follow local law plus ventilation and protection requirements.
- Some historical entries describe processes involving hazardous materials (e.g. mercury or arsenic compounds). They are reference material only and must not be attempted without specialist supervision.
- Service is provided for overseas users; registrations from mainland China (including Hong Kong, Macao and Taiwan) are not accepted.
Accuracy
Entries are compiled from historical and published sources. We do not guarantee they are error-free. If an unlocked entry has a material factual error, the Refund Policy lets you swap it for a same-value entry or get a refund. Verify critical data before use.