Okay, the user wants me to translate "alkalinity determination" into Japanese. Let me check the rules again. The first rule says to translate all content into Japanese. The second rule states that if the content is already in Japanese, leave it as is. The third rule is to provide only the translation without any explanations.
So, "alkalinity determination" is in English. I need to translate it. The term "alkalinity" in Japanese is usually "アルカリ性" (arukari-sei), which refers to the property of being alkaline. "Determination" here likely means the process of determining or measuring, so "測定" (sokutei) for measurement or "判定" (hakai) for determination. However, in a scientific context, "測定" is more commonly used for measurements like pH or alkalinity levels.
Putting it together, "alkalinity determination" would be "アルカリ性の測定" (arukari-sei no sokutei), which translates to "measurement of alkalinity." I should make sure there's no existing Japanese text that's already correct. Since the user provided an English term, the translation is necessary. No explanations, just the result. So the answer is "アルカリ性の測定".