fix: 1.修复新beta在分析时没有识别到核素之后没有对exist进行赋值的问题

This reverts commit 28786f37c97c38081c6e1dc735a00c0bbf4e34c3.

jeecg-module-beta-gamma-analyser/src/main/java/org/jeecg/common/util/SelfBaseUtil.java

@@ -863,6 +863,7 @@ public class SelfBaseUtil extends AbstractLogOrReport {
                 for (int i = (int)lc; i <= (int) rc; i++) {
                     area += counts.get(i);
                 }
+                nuclideParam.put("exist", false);
                 nuclideParam.put("area", area+"");
             }
             param.put(mapKey, nuclideParam);