NDT Check | Non Destructive Testing

Decay Chart of Se-75 | Decay Chart of Selenium-75 | Decay calculation for Se-75 | Decay Calculation for Selenium-75

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Introduction:

Selenium (Se-34) has six natural isotopes that occur in significant quantities, along with the trace isotope Se-79, which occurs in minute quantities in uranium ores. Five of these isotopes are stable: Se-74, Se-76, Se-77, Se-78, and Se-80. The last three also occur as fission products, along with Se-79, which has a half-life of 327,000 years, and Se-82, which has a very long half-life (~1020 years, decaying via double beta decay to Kr-82) and for practical purposes can be considered to be stable. There are 23 other unstable isotopes that have been characterized, the longest-lived being Se-79 with a half-life 327,000 years, Se-75 with a half-life of 120 days, and Se-72 with a half-life of 8.40 days. Of the other isotopes, Se-73 has the longest half-life, 7.15 hours, most others have half-lives not exceeding 38 seconds.

Se-75 Decay Formula:

A(time) = A(Load) exp (-0.69315 time/TH)

The decrease of activity of a radioisotope with time is given by the equation Where A(Load) is the initial activity at source is Loading, A(time) is the activity after a further some day or months time has elapsed, and TH is the half-life of the radioisotope here Selenium-75 half life is 119.8 Day's, expressed in the same units as time of some day or months.  The ratio A(time)/A(Load) is called the decay factor of the radioisotope for elapsed some day or months "time'.  Decay factors for various radioisotopes and for various elapsed times are tabulated below. To determine the final activity of an isotope, multiply the current activity by the decay factor in the correct table.

Day Calculation between two Date:

Day calculation is important for decay chart, day calculation between two date one is Activity Loading Date and second Date is source use or find source Activity after some day's or some month's

Calculate Difference Between Two Dates (in Days)

Select First Date (mm/dd/yyyy):

Select Second Date (mm/dd/yyyy):

Difference between Two Date is:

Decay Chart of Se-75 Table | Decay Chart of Selenium-75 Table

Day's	Activity		Day's	Activity		Day's	Activity
0	1.000000		302	0.174237		604	0.030358
2	0.988495		304	0.172232		606	0.030009
4	0.977122		306	0.170251		608	0.029664
6	0.965880		308	0.168292		610	0.029323
8	0.954768		310	0.166356		612	0.028985
10	0.943783		312	0.164442		614	0.028652
12	0.932925		314	0.162550		616	0.028322
14	0.922191		316	0.160680		618	0.027996
16	0.911581		318	0.158831		620	0.027674
18	0.901094		320	0.157004		622	0.027356
20	0.890726		322	0.155197		624	0.027041
22	0.880479		324	0.153412		626	0.026730
24	0.870349		326	0.151647		628	0.026422
26	0.860335		328	0.149902		630	0.026118
28	0.850437		330	0.148177		632	0.025818
30	0.840653		332	0.146473		634	0.025521
32	0.830981		334	0.144787		636	0.025227
34	0.821420		336	0.143122		638	0.024937
36	0.811970		338	0.141475		640	0.024650
38	0.802628		340	0.139847		642	0.024367
40	0.793394		342	0.138238		644	0.024086
42	0.784266		344	0.136648		646	0.023809
44	0.775243		346	0.135076		648	0.023535
46	0.766323		348	0.133522		650	0.023264
48	0.757507		350	0.131986		652	0.022997
50	0.748792		352	0.130467		654	0.022732
52	0.740177		354	0.128966		656	0.022471
54	0.731661		356	0.127482		658	0.022212
56	0.723243		358	0.126016		660	0.021957
58	0.714922		360	0.124566		662	0.021704
60	0.706697		362	0.123133		664	0.021454
62	0.698566		364	0.121716		666	0.021207
64	0.690529		366	0.120316		668	0.020963
66	0.682585		368	0.118931		670	0.020722
68	0.674731		370	0.117563		672	0.020484
70	0.666968		372	0.116210		674	0.020248
72	0.659295		374	0.11873		676	0.020015
74	0.651710		376	0.113552		678	0.019785
76	0.644212		378	0.112245		680	0.019557
78	0.636800		380	0.110954		682	0.019332
80	0.629474		382	0.109677		684	0.019110
82	0.622231		384	0.108416		686	0.018890
84	0.615073		386	0.107168		688	0.018673
86	0.607996		388	0.105935		690	0.018458
88	0.601001		390	0.104717		692	0.018245
90	0.594086		392	0.103512		694	0.018036
92	0.587251		394	0.102321		696	0.017828
94	0.580495		396	0.101144		698	0.017623
96	0.573816		398	0.099980		700	0.017420
98	0.567215		400	0.098830		702	0.017220
100	0.560689		402	0.097693		704	0.017022
102	0.554238		404	0.096569		706	0.016826
104	0.547861		406	0.095458		708	0.016632
106	0.541558		408	0.094359		710	0.016441
108	0.535328		410	0.093274		712	0.016252
110	0.529169		412	0.092201		714	0.016065
112	0.523080		414	0.091140		716	0.015880
114	0.517062		416	0.090091		718	0.015697
116	0.511113		418	0.089055		720	0.015517
118	0.505233		420	0.088030		722	0.015338
120	0.499420		422	0.087017		724	0.015162
122	0.493974		424	0.086016		726	0.014987
124	0.487995		426	0.085027		728	0.014815
126	0.482380		428	0.084048		730	0.014644
128	0.476830		430	0.083081		732	0.014476
130	0.471344		432	0.082126		734	0.014309
132	0.465922		434	0.081181		736	0.014145
134	0.460561		436	0.080247		738	0.013982
136	0.455262		438	0.080247		740	0.013821
138	0.450024		440	0.078411		742	0.013662
140	0.444847		442	0.077509		744	0.013505
142	0.439729		444	0.076717		746	0.013350
144	0.434670		446	0.075735		748	0.013196
146	0.429669		448	0.074864		750	0.013044
148	0.424726		450	0.074003		752	0.012894
150	0.419839		452	0.073151		754	0.012746
152	0.415009		454	0.072310		756	0.012599
154	0.410234		456	0.071478		758	0.012454
156	0.405514		458	0.070656		760	0.012311
158	0.400849		560	0.069843		762	0.012169
160	0.396237		462	0.069039		764	0.012029
162	0.391678		464	0.068245		766	0.011892
164	0.387172		466	0.067460		768	0.011754
166	0.382717		468	0.066683		770	0.011619
168	0.378314		470	0.065916		772	0.011485
170	0.373962		472	0.065158		774	0.011353
172	0.369659		474	0.064408		776	0.011222
174	0.365406		476	0.063667		778	0.011093
176	0361202		478	0.062935		780	0.010966
178	0.357047		480	0.062211		782	0.010839
180	0.352939		482	0.061495		784	0.010715
182	0.348878		484	0.060787		786	0.010591
184	0.344864		486	0.060088		788	0.010470
186	0.340897		488	0.059397		790	0.010349
188	0.336975		490	0.058713		792	0.010230
190	0.333098		492	0.058038		794	0.010112
192	0.329265		494	0.057370		796	0.009996
194	0.325477		496	0.056710		798	0.009881
196	0.21732		498	0.056058		800	0.009767
198	0.318031		500	0.055413		802	0.009655
200	0.314372		502	0.054775		804	0.009544
202	0.310755		504	0.054145		806	0.009434
204	0.307180		506	0.053522		808	0.009326
206	0.303646		508	0.052906		810	0.009218
208	0.300152		510	0.052298		812	0.009112
210	0.296699		512	0.051696		814	0.009007
212	0.293285		514	0.051101		816	0.008904
214	0.289911		516	0.050513		818	0.008801
216	0.286576		518	0.049932		820	0.008700
218	0.283279		520	0.049358		822	0.008600
220	0.280019		522	0.048790		824	0.008501
222	0.276798		524	0.048228		826	0.008403
224	0.273613		526	0.047673		828	0.008306
226	0.270465		528	0.047125		830	0.008211
228	0.267353		530	0.046583		832	0.008116
230	0.264278		532	0.046047		834	0.008023
232	0.261237		534	0.045517		836	0.007931
234	0.258231		536	0.044993		838	0.007840
236	0.255260		538	0.044476		840	0.007749
238	0.252324		540	0.043964		842	0.007660
240	0.249421		542	0.043458		844	0.007572
242	0246551		544	0.042958		846	0.007485
244	0.253724		546	0.042464		848	0.007399
246	0.240911		548	0.041975		850	0.007314
248	0.238139		550	0.041493		852	0.007230
250	0.235399		552	0.041015		854	0.007146
252	0.232691		554	0.040543		856	0.007064
254	0.230014		556	0.040077		858	0.006983
256	0.227367		558	0.039616		860	0.006903
258	0.224751		560	0.039160		862	0.006823
260	0.222166		562	0.038709		864	0.006745
262	0.219610		564	0.038264		866	0.006667
264	0.217083		566	0.037824		868	0.006590
266	0.214585		568	0.037389		870	0.006514
268	0.212117		570	0.036959		872	0.006440
270	0.209676		572	0.036533		874	0.006365
272	0.207264		574	0.036113		876	0.006292
274	0.204879		576	0.035698		878	0.006220
276	0.202522		578	0.035287		880	0.006148
278	0.200192		580	0.034881		882	0.006078
280	0.197889		582	0.034480		884	0.006008
282	0.195612		584	0.034083		886	0.005938
284	0.193362		586	0.033691		888	0.005870
286	0.191137		588	0.033303		890	0.005803
288	0.188938		590	0.032920		892	0.005736
290	0.186764		592	0.032541		894	0.005670
292	0.184615		594	0.032167		896	0.005605
294	0.182491		596	0.031797		898	0.005540
296	0.180392		598	0.031431		900	0.005476
298	0.178316		600	0.031069		902	0.005413
300	0.176265		602	0.030712		904	0.005351