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We re-examine the effects of pairing gaps on charge-changing transitions and the associated β -decay half-lives. Calculations are performed using the proton-neutron quasiparticle random phase approximation (pn-QRPA) model for 250 nuclei possessing astrophysical significance. Pairing gaps between like nucleons are key model parameters in the pn-QRPA approach. Three different values of empirically computed pairing gaps were used as input parameters in our nuclear model. Changing the pairing gap values significantly altered the Gamow-Teller distributions including the total strength and centroid values. The β -decay half-lives also changed substantially. The half-lives computed via the three-term pairing formula, based on separation energies of nucleons, were in best agreement with the measured data. [ABSTRACT FROM AUTHOR]

There is an experimental attempt to synthesize superheavy elements Z=120 at various labs. Superheavy nuclei are highly unstable and decay through channels such as alpha decay, spontaneous fission, cluster decay, and heavy particle decay. In this context, we have studied all possible decay modes for superheavy nuclei 302 120 using a Modified Generalized Liquid Drop Model (MGLDM). The half-lives produced by the present model are validated with experiments. By studying the competition between different decay modes, it is observed that the superheavy nuclei 302 120 shows alpha decay. The decay chain of 302 120 is presented. It undergoes three alpha decay chains and terminates with spontaneous fission. The present study is certainly useful in the synthesis of superheavy elements. [ABSTRACT FROM AUTHOR]

The identification of changes in tumor markers (TMs) in cancer patients that indicate response to treatment, stabilization or disease progression is a challenge for laboratory medicine. Several approaches have been proposed: assessing percentage increases, applying discriminant values, and estimating half-life (t1/2) or doubling time (DT). In all of them it is assumed that the TM is a surrogate of the variation in tumor size. In general this variation is time-dependent, but this is not the case of intraindividual biological variability (CVi), which can range from 6 % in CA15-3 to 22 % in CA125. When decisions are made on the basis of DT or t1/2, these values can be affected by the CVi; if it is very large, the growth rate very slow and the period of time between determinations very short, the result obtained for DT may be due mainly to the CVi. The aim of this study is to establish the relationship between the CVi and temporal variables. We related equations for calculating DT and t1/2 to the reference change values in tumor markers. The application of the formula obtained allows the calculation of the optimal time between measurements to ensure that the influence of the CVi is minimal in different types of tumors and different scenarios. Intraindividual variation affects the calculation of DT and t1/2. It is necessary to establish the minimum time between two measurements to ensure that the CVi does not affect their calculation or lead to misinterpretation. [ABSTRACT FROM AUTHOR]

We explored one and two proton radioactivity in 141–229Tm nucleus isotopes. An effective liquid drop model is used to calculate the proton decay half-lives. The WKB integral is used to calculate the penetration probability. The half-lives of one and two proton radioactivity are compared to those of β ± and α decay. Furthermore, proton-decay, beta-decay, and alpha-decay half-lives are compared to experimental results. The result derived from the current investigation is consistent with previous experimental data. Further, we have identified potential proton emitters and β - emitters in the unexplored regions of mass number range 141 ≤ Z ≤ 146 and 48 β - -emitters in the mass number range 182 ≤ Z ≤ 229 for Thulium nuclei. The existence of positive Q values for these isotopes was estimated through theoretical calculations, as experimental data on mass excesses in these regions are currently unavailable. These newly found isotopes have potential use in medical imaging, treatment of cancer, dosimetric studies, and radio-guided surgery. [ABSTRACT FROM AUTHOR]

The spontaneous fission (SF) half-lives of all 96 experimentally accessible SF emitters were examined. The SF emitters are classified as even Z-even A, odd Z-even A, odd Z-odd A and even Z-odd A. A plot of log T 1 ∕ 2 + k δ m versus Z 2 ∕ A demonstrates a straight line, where k is variable. The log T 1 ∕ 2 values produced in this study are compared to all other semi-empirical relations such as Ren et al., [Nucl. Phys. A 759, 64 (2005)], Xu et al., [Phys. Rev. C 78, 044329 (2008)], Santhosh et al., [Nucl. Phys. A 832, 220 (2010)] and Karpov et al., [Int. J. Mod. Phys. E 21, 1250013 (2012)] available in the literature. When compared to earlier semi-empirical equations accessible in the literature, the new formula shows reduced uncertainty in standard deviation in the case of Odd Z-even A and even Z-Odd A nuclei. When compared to other sets of combinations (even Z-even A, and odd Z-odd A nuclei), this study more accurately reproduces the experimental SF half-lives for even Z-odd A and odd Z-even A nuclei with smaller σ in the atomic number range 9 0 ≤ Z ≤ 1 12 and mass number range 23 2 ≤ A ≤ 2 84. [ABSTRACT FROM AUTHOR]

β -decay is one of the key factors for understanding the r-process and evolution of massive stars. The Gamow–Teller (GT) transitions drive the β -decay process. We employ the proton–neutron quasiparticle random phase approximation (pn-QRPA) model to calculate terrestrial and stellar β -decay rates for 50 top-ranked nuclei possessing astrophysical significance according to a recent survey. The model parameters of the pn-QRPA model affect the predicted results of β -decay. The current study investigates the effect of nucleon–nucleon pairing gaps on charge-changing transitions and the associated β decay rates. Three different values of pairing gaps, namely TF, 3TF, and 5TF, were used in our investigation. It was concluded that both GT strength distributions and half-lives are sensitive to pairing gap values. The 3TF pairing gap scheme, in our chosen nuclear model, resulted in the best prediction with around 80% of the calculated half-lives within a factor 10 of the measured ones. The 3TF pairing scheme also led to the calculation of the biggest β -decay rates in stellar matter. [ABSTRACT FROM AUTHOR]

We studied the alpha decay half-life of Americium isotopes (Z = 9 5) with mass numbers ranging from 223 to 243. Our investigation employed the Coulomb and proximity potential model (CPPM), in addition to alternative analytical and semiempirical formulas. The calculations took into account both experimental and theoretical Q-values, as well as the total alpha kinetic energy. We analyzed the behavior of the hindrance factor concerning changes in the mass numbers of parent nuclei within the range of 223–243, and also examined the impact of magic numbers associated with closed shells. To evaluate the accuracy of our findings, we utilized the SemFIS, UNIV, and Royer formulas to make predictions, which were then compared to the existing experimental data. [ABSTRACT FROM AUTHOR]

Residue studies were conducted in bell pepper crops (green and yellow bell pepper) to ensure the safe use of fenvalerate, profenofos, and novaluron (under open field and protected conditions) in randomized block design (RBD) following three applications at a 10-day interval over two consecutive years, 2021 and 2022. A robust analytical method was developed using quick, easy, cheap, effective, rugged, and safe (QuEChERS) extraction and gas chromatography-tandem mass spectrometry (GC–MS/MS) for the determination of pesticide residues in bell pepper samples. The half-lives for fenvalerate were 2.47–2.87 and 2.50–3.03 days on bell pepper under open field conditions, whereas the corresponding values for bell pepper under protected conditions were 3.84–4.58 and 4.17–4.71 days, during 2021 and 2022, respectively. Profenofos displayed half-lives of 2.03–2.65 and 2.15–2.77 days in open field conditions and 3.05–3.89 and 3.16–3.78 days in protected conditions during 2021 and 2022, respectively. Similarly, novaluron had half-lives of 2.87–3.49 and 3.24–3.75 days under protected conditions in 2021 and 2022, respectively. The maximum residue limits (MRLs) were calculated to be 0.6 mg/kg for fenvalerate, while for profenofos it was 0.7 mg/kg on bell pepper under open field conditions at double doses, at the proposed pre-harvest interval (PHI) of 3 days. Likewise, for bell peppers grown under protected conditions, MRLs at the PHI of 3 days were determined to be 0.8 mg/kg for fenvalerate, 0.3 mg/kg for novaluron, and 1.5 mg/kg for profenofos. A dietary risk assessment study indicated that the percentage of acute hazard index (% aHI) was significantly lower than 100, and hazard quotient (HQ) values were below 1, signifying no acute or chronic risk to consumers. These findings underscore the safety of consuming bell peppers treated with fenvalerate, profenofos, and novaluron under the protected and open field conditions. [ABSTRACT FROM AUTHOR]

The isotopic yield and half-lives of the spontaneous fission of superheavy nuclei Z = 1 1 9 and Z = 1 2 0 are studied. First, the theoretical formalism is validated by applying it to known isotopes of superheavy nuclei which can undergo spontaneous fission. Half-lives obtained from this work indicate that all the half-lives are approximately twice when compared to experimental measurements. Thereafter, we explored the isotopic yield and half-lives of spontaneous fission for the superheavy nuclei Z = 1 1 9 and Z = 1 2 0 by studying the driving potential, yield and penetration probability. The superheavy nuclei Z = 1 1 9 can undergo alpha decay up to A = 3 0 6. Thereafter they undergo spontaneous fission. Similarly, the superheavy nuclei Z = 1 2 0 undergo spontaneous fission beyond A=309. It is observed that the superheavy nuclei Z = 1 1 9 undergo spontaneous fission through the fission fragment combination of Sn+Tm, however, the superheavy nuclei Z = 1 2 0 undergo spontaneous fission with the fragments Sn+Yb. The larger spontaneous half-life is of the order of ns from the superheavy nuclei 3 0 7 119 and 3 1 0 120. Further investigations were required in the evaluation of the anticipated fission fragment combinations and half-lives of 3 0 7 − 3 1 0 119 and 3 1 0 − 3 1 3 120. [ABSTRACT FROM AUTHOR]

In this paper, we systematically studied half-lives of the different decay modes using various theoretical models such as the unified fission model (UFM) and the effective liquid drop model. Beta-decay half-lives were evaluated using semi-empirical formulae available in the literature. We compared half-lives of all the studied decay modes and identified shorter half-lives among the same in 2 0 5 − 2 3 3 Ac nuclei. We investigated the actinium series which is similar to the thorium series. Among these decay series, alpha-emitting isotopes show great promise for cancer treatment because of their short path length and high-energy transfer of radiation. Furthermore, we predicted the decay chains of the actinium isotopes. All the decay series of actinium ends with the formation of stable nuclei or with longer half-lives. The predicted decay series and new isotopes during the decay process are helpful in the field of medicine and radiotherapy. [ABSTRACT FROM AUTHOR]

Within the macroscopic approach, investigation of different decay modes such as alpha-decay, cluster-decay (12C to 40Ca), heavy particle radioactivity (HPR) (58Ni to 85Rb), and spontaneous fission (SF) half-lives are investigated in detail in the superheavy element (SHE), Z = 119. The decay energies, penetration probability, and different decay half-lives in the isotopes of synthesized superheavy nuclei (SHN) 290–303119 are evaluated. Both 12C and 40Ar cluster emissions reveal shorter half-lives when compared to other cluster emissions. Furthermore, 85Rb heavy particle emission from the SHN 290–303119 discloses shorter half-lives compared to other heavy particle emissions. From the comparison of different decay half-lives, it is observed that 85Rb HPR is dominant in the region 290–299119, alpha-decay is dominant for the 300–302119, and SF half-lives are predominant in 303119 nuclei. Hence, the prediction of decay modes and decay path in the SHE, Z = 119 are helpful in the identification of experimentally synthesized SHE. [ABSTRACT FROM AUTHOR]

β-decay is one of the key factors for understanding the r-process and evolution of massive stars. The Gamow–Teller (GT) transitions drive the β-decay process. We employ the proton–neutron quasiparticle random phase approximation (pn-QRPA) model to calculate terrestrial and stellar β-decay rates for 50 top-ranked nuclei possessing astrophysical significance according to a recent survey. The model parameters of the pn-QRPA model affect the predicted results of β-decay. The current study investigates the effect of nucleon–nucleon pairing gaps on charge-changing transitions and the associated β decay rates. Three different values of pairing gaps, namely TF, 3TF, and 5TF, were used in our investigation. It was concluded that both GT strength distributions and half-lives are sensitive to pairing gap values. The 3TF pairing gap scheme, in our chosen nuclear model, resulted in the best prediction with around 80% of the calculated half-lives within a factor 10 of the measured ones. The 3TF pairing scheme also led to the calculation of the biggest β-decay rates in stellar matter.

The cluster decay (CD) half-lives (HL) are investigated using the Coulomb and proximity potential model (CPPM) and modified generalized liquid drop model (MGLDM). The proximity functions Prox-13[European Physical Journal A 49, 1 (2013)], MP-77 [Annals of Physics 132, 53 (1981), Pramana 76, 921 (2011)], Prox-77 [Annals of Physics 105, 427 (1977)], MP-81 [Annals of Physics 132, 53 (1981)], Ng-80[Nuclear Physics A 348, 140 (1980)] and DP-00 [Physics Letters B 526, 315 (2002)] were used to evaluate CD half-lives. The mass excess FRLDM will more precisely reproduce experimental decay energy. The computed CD half-lives using the Prox-13 function can more closely reflect experimental data. The decay half-lives of odd superheavy nuclei (SHN) within the atomic number (Z) range 105 ≤ Z ≤ 125 for cluster emission from helium to calcium are expected. The entrance channel parameters on the logarithmic half-lives (LHL) provide insight into future cluster radioactivity (CR) experiments. [ABSTRACT FROM AUTHOR]

A thorough study on one-proton and two-proton radioactivity is carried in the atomic number range 3 ≤ Z ≤ 126 using well-accepted Coulomb and proximity potential model (CPPM), effective liquid drop model, generalized liquid drop model and modified generalized liquid drop model. The proton decay half-lives produced by these models are compared with those of experiments. Predictive power of these models is assessed by evaluation of the mean squared error, and it can be concluded that CPPM model produces proton decay half-lives close to experiments. Furthermore, we constructed semi empirical formula for one- and two-proton decay half-lives by including angular momentum term. The values produced by the present formula are also compared with experiments. Around 241 and 174 energetically feasible pure one- and two-proton emitters are identified in the atomic number range 3 ≤ Z ≤ 126 . [ABSTRACT FROM AUTHOR]

Effect of deformation on half-life of two-proton (2p) radioactivity is investigated across the periodic chart for nuclei with Z < 82. 2p-decay half-lives are estimated by employing our newly proposed semi-empirical formula wherein the nuclear deformation has been incorporated in a phenomenological way. Robustness of the formula is demonstrated as it estimates the measured values quite accurately and, hence, reliably applied to predict the other possible 2p-emitters. For many proton rich nuclei for which experimental data on the decay energies are not available, we have used the theoretical values obtained from our calculations using the relativistic mean-field approach. The uncertainties in the theoretical decay energy values are minimised by machine learning technique. Correlation of 2p-radioactivity with 2p-halo and deformation is probed. Our calculations show the phenomenon of shape coexistence in several 2p-emitters, wherein the prolate shape is found to be more predominant for the ground state. [ABSTRACT FROM AUTHOR]

The data on the dynamics of the 137Cs transfer coefficients (Tf) for fodder in the long term after the Chernobyl accident (2008–2020) are presented. It is shown that the ecological half-lives of transfer coefficients varied from 7.8 to 28.9 years. The obtained estimates are consistent with the second half-life periods of transfer coefficients estimated based on data for the first eight years after the Chernobyl accident. The peculiarities of the dynamics of Tf to fodder were in good agreement with the scales of remedial actions carried out in the contaminated territories. [ABSTRACT FROM AUTHOR]

We have studied the alpha decay properties of actinides using seven different proximity potentials MP 77, MP 81, Bass 77, Prox 13, Ng80, DP00 and Prox 00. The values produced by the present work are compared with experiments. Decay chains of actinides are presented. The present work is useful in the study of decay modes of actinides. [ABSTRACT FROM AUTHOR]

The half-lives of cluster radioactivity are investigated using a modified generalized liquid-drop model (MGLDM). The radioactive decay with different cluster emissions in the isotopes of He, Li, Be, Ne, Na, Mg, Al, Si, P Ar, K and Ca nuclei are studied. The cluster radioactivity half-lives have been evaluated within WKB integral method. The estimated cluster decay half-lives from the present work precisely reproduce the experimental data. Predictions are made in the even superheavy nuclei in the atomic number range 104 ≤ Z ≤ 126 . The role of Coulomb effect ( Z 2 / A 2 / 3 ), asymmetry effect ( (N - Z) 2 / A ), pairing effect ( A ) and shell effect on cluster radioactivity are studied. [ABSTRACT FROM AUTHOR]

[Display omitted] • Dry conservation is preferred to brine conservation with 60 % residue removal. • An average of 2% of the pesticide residues passed into the brine. • Washing with boiling water is recommended with 30 % residue removal. • Health risk assessment shows no risk in extreme scenarios, with Hazard Quotients < 1. The effect of vine leaves processing techniques on Azoxystrobin, Fenazaquin, and Indoxacarb residues was investigated. Residue extraction following field application of pesticides and leaf processing was carried out using the QuEChERS method, with analysis conducted by LC-MS/MS. In dry conservation, Azoxystrobin's half-life was estimated to exceed a year, Fenazaquin's was 18 days, and Indoxacarb's was 142 days. Azoxystrobin had a half-life of 261 days, Fenazaquin had a half-life of 9 days, and Indoxacarb's half-life exceeded a year in brine conservation. It is recommended to use dry conservation because it results in an average 60 % reduction in residue levels for the three pesticides. Boiling water significantly reduced pesticide residues (Azoxystrobin −40.3 %, Indoxacarb –22.4 %, and Fenazaquin −28.8 %). It is recommended to use boiling water for washing, as it shows an average removal rate of approximately 30 %. The health risk assessment indicated that consuming vine leaves posed no health risk for consumers, but overall exposure to residues must be considered. [ABSTRACT FROM AUTHOR]

To follow up field observations in the Chornobyl Exclusion Zone (ChEZ), a series of controlled model aquarium experiments were conducted to determine the uptake and depuration rates of 137Cs and 90Sr in silver Prussian carp (Carassius gibelio) in fresh water, varying in temperature from 5 to 27 °C, with daily feeding rates of 0–1.5 % fish weight day−1. In the present study, the 137Cs uptake rates in muscle tissues directly from water, 0.05–0.09 day−1 at temperatures of 5–27 °C, were significantly lower than previously reported for fish fed under natural conditions in contaminated lakes within the ChEZ. The rate of 90Sr uptake in bone tissues of silver Prussian carp varied from 0.055 day−1 at a water temperature of 5 °C and feeding rates ≤0.15 % fish weight day−1 to 1.5 ± 0.2 day−1 at a temperature of 27 ± 1 °С and at the highest tested feeding rate of 1.5 % day−1. The rate of decrease of 137Cs concentration in muscle tissues was k b = 0.0028 ± 0.0004 day−1 (T 1/2 = 248 ± 35 days) at the lowest water temperature tested (5 °С). At water temperatures between 13 and 26 °С and a feeding rate of 0.15 % day−1, the rate increased to k b = 0.0071–0.0092 day−1 (T 1/2 = 75–99 days). The rates of decrease of 90Sr activity concentration in bone tissues at water temperatures between 22 and 25 °С and a feeding rate of 0.5 % day−1 were k b = 0.004–0.0014 day−1, and the associated biological half-life T 1/2 ranged 50–160 days, respectively. The present work supported conclusions related to the main pathways of 137Cs and 90Sr uptake by silver Prussian carp, and demonstrated the usefulness of combining field and laboratory uptake and depuration experiments. • The 137Cs uptake rate by fish from water is 5–100 times lower than from contaminated food. • The 137Cs uptake rate by fish from water increased at high water temperatures. • The 90Sr uptake rate by fish from water is much higher than from contaminated food. • The 90Sr uptake rate from water increased with increasing water temperature and feeding rate. • The rates of decrease in 137Cs and 90Sr concentrations increase due to biodilution. [ABSTRACT FROM AUTHOR]

This paper investigates the predictive power of the macroscopic and microscopic models in alpha-decay of actinide nuclei. Macroscopic theoretical models such as Coulomb and Proximity potential model (CPPM), Modified generalized liquid drop model (MGLDM) and Effective liquid drop model (ELDM) are applied in predicting the alpha-decay half-lives of actinide nuclei. The half-lives produced by these macroscopic models are compared with that of microscopic models such as Cluster model with two-potential approach (CM), Microscopic cluster model (MCM), Multichannel cluster model (MCCM) and that of experiments. The deviation of these models with the experiments is quantified using statistical treatment such as root mean square deviation σ (RMSD), mean deviation ( δ ̄), index f ̄ and root mean square error (RMSE). It is found that among the microscopic and macroscopic models, ELDM and MCCM are, respectively, found to be accurate than that of other models. The microscopic model MCCM produces alpha-decay half-lives close to the experiments in the actinide region. The appropriate mass excess values have been identified to predict the exact alpha-decay half-lives in the actinide region. [ABSTRACT FROM AUTHOR]

Many fusion reactions such as 50 T i + 249 C f , 51 V + 249 B k , 54 C r + 248 C m , 55 M n + 243 A m , 58 F e + 244 P u , 59 C o + 237 N p , 64 N i + 238 U failed to synthesis the superheavy element with Z=120. This may be due to the tendency of fission of the formed compound nuclei. It is important to study the fission of the compound nuclei formed through fusion. The binary fission of superheavy the nuclei 290 - 304 120 has been studied using a modified generalized liquid drop model. All favorable fragment combinations are considered, while studying the driving potential, the logarithmic half-lives and the relative yield. The shorter half-lives and larger relative yield are observed when the mass and charge asymmetry is reduced. The signature of the failure to synthesize the superheavy element with Z=120 through these fusion reactions may be visualized by identification of fission fragments. The present work identifies the fission fragments with corresponding half-lives of compound nuclei formed through fusion. Hence, the present work may be successful in searching the reason for failure of the attempted fusion reactions to synthesis superheavy element Z=120. [ABSTRACT FROM AUTHOR]

The existence of neutron magic number 184 is demonstrated through the cluster decay studies. The alpha and black cluster radioactivity have been studied in the superheavy region 1 0 4 ≤ Z ≤ 1 2 6 using modified generalized liquid drop model (MGLDM). The values obtained from this work were compared with that of experiments. During the study of black cluster radioactivity, surprisingly it is observed that the shortest half-lives of cluster decay in all superheavy elements are observed for daughter neutron number 184 and nearly equal to that. This is a clear evidence for the existence of the neutron magic number N = 1 8 4. This study is useful in the understanding of superheavy element nuclei structure. [ABSTRACT FROM AUTHOR]

The radioactivity of the superheavy nuclei 250 - 275 Db is studied and presented using the Coulomb and proximity potentials. The half-lives corresponding to different decay modes such as α , cluster decay ( 12 C, 14 N, 18 , 20 O, 23 F, 20 Ne, 34 S, 28 Mg and 40 Ca) and spontaneous fission in the superheavy nuclei 250 - 275 Db are studied. The studied half-lives are compared with the available experiments. The decay modes and the branching ratios of isotopes of dubnium are presented. The isotopes of dubnium, 254 - 263 Db, are identified as α emitters, whereas isotopes such as 250 - 253 Db and 264 - 275 Db are identified as having spontaneous fission. The identified alpha emitting isotopes of dubnium have decay energies from 6 MeV to 10 MeV and half-lives 1 ms to 100 s. The possible projectile–target combinations to synthesise the superheavy nuclei 253 - 263 Db were predicted. The fusion of spherical projectile and target yields larger evaporation residue cross-sections. [ABSTRACT FROM AUTHOR]

In this paper, we have made an attempt to analyze the alpha-decay half-lives of in the atomic number range 6 2 ≤ Z ≤ 1 1 8 by considering an effective liquid drop model. The role of pre-formation probability by including iso-spin effect is included during an evaluation of half-lives. We have also compared the studied alpha-decay half-lives with that of semi-empirical formulae such as Viola Seaborg semi-empirical formulae (VSS) [J. Inorg. Nucl. Chem. 28 (1966) 741; Nucl. Phys. A 848 (2010) 279], Royer formulae [J. Phys. G: Nucl. Part. Phys. 26 (2000) 1149; Phys. Rev. C 101 (2020) 034307] and also with that of the available experiments. From this comparison, it can be concluded that the effective liquid drop model produces an alpha-decay half-lives close to the experiments. [ABSTRACT FROM AUTHOR]

The most possible alpha-accompanied ternary fission fragment of 217-219Ac are studied using Coulomb and proximity potential model. We have studied driving potential (V-Q), logarithmic half-lives and relative yield of all possible fission fragments. From the present work, the minimum driving potential, maximum relative yield and minimum half-lives are observed for the fragment combination of 4He+209-211Ac+4He for the nuclei 217-219Ac. Hence, this fission fragment combination is considered as most possible fission fragments due to presence of doubly magic nuclei. This study is important in near future experiments. [ABSTRACT FROM AUTHOR]

Using different models such as Coulomb and proximity potential model, effective liquid drop model and modified generalised liquid drop model, we have studied all possible one proton radioactivity tantalum. The calculated half-lives from the present work are compared with the available experiments. One proton decay energy is studied using recent mass excess values [Chinese Physics C Vol. 45, No. 3 (2021) 030003]. The angular momentum dependence of potential have been considered. The penetration probability ( P ) is studied using WKB integral. The decay constant ( ) and halflives (T 2/1 ) of 151-157Ta were predicted. The identified one proton radioactivity of 151-157Ta along with half-lives and decay energies plays an important role in the future experiments. Present work may find useful applications in radiotherapy and diagnosis. [ABSTRACT FROM AUTHOR]

Using modified generalized liquid drop model, we have studied all possible cluster decay modes of superheavy nuclei 287Mc using different nuclear potentials. The daughter or residual nuclei is having magic nuclei or semi-magic nuclei. The total potential is evaluated by considering quantum tunneling process. The lower limit of cluster emission is from Zmin e = 2 and upper limit of cluster emission considered is Zmax e = Z - 82 . The studied different nuclear potentials such as Danisov, AW-91, BW-91 and Bass-73 shows shorter half-lives and larger relative yield for the cluster emission 74Ge. Hence, the possible cluster decay is with the combination 74Ge+213Bi. [ABSTRACT FROM AUTHOR]

In a rapidly changing shape phase region, the presence of shape coexistence and its possible impact on the decay modes and half-lives, has been explored in astrophysically interesting Mo and Ru isotopes, in an extensive study within the microscopic theoretical framework using Nilsson Strutinsky Method and Relativistic Mean Field Model. The isotopic chains of Mo and Ru exhibit rapid shape phase transitions, triaxial γ softness, shape instability along with many coexisting states mostly with oblate and triaxial shapes. Proton and neutron separation energies have been calculated and compared with the available data. Results obtained from both the formalisms are in good agreement with each other as well as the available experimental data. Our computed β -decay half-lives and separation energy for nuclei exhibiting shape coexistence were examined for the decay mode from second minima state of the parent nuclei to the ground or excited state of the daughter nuclei. The second minima state of the coexisting shapes in Mo and Ru isotopes, were seen to impact the structural properties, β -decay half-lives, separation energy and hence the stability of the nuclei. [ABSTRACT FROM AUTHOR]

The alpha decay half-lives of actinides within modified generalized liquid drop model (MGLDM) are investigated by the Wentzel–Kramers–Brillouin (WKB) barrier penetration probability. The potential barrier was studied taking in to account of nuclear proximity, coulomb interaction and centrifugal potential with the inclusion of angular momentum. This work predicts the alpha decay half-lives of unknown actinide nuclei such as 2 4 8 Am, 2 3 5 , 2 3 7 , 2 5 2 Cm, 2 4 8 , 2 5 2 , 2 5 3 Bk, 2 4 7 Es and 2 4 8 No. The calculated alpha decay half-lives reproduce accurately the experimental data. The predictions provided for the alpha decay half-lives within the MGLDM may be helpful for identifying the new isotopes in this field. [ABSTRACT FROM AUTHOR]

Theoretical possibilities for the spontaneous emission of fission fragments from 2 3 7 − 2 5 6 Cf parents are investigated within the framework of preformed cluster decay model (PCM). The fragmentation potential exhibits a modification from dominated asymmetric fission profile to symmetric splitting with the rise in the N/Z ratio of parent nuclei. The calculated spontaneous fission (SF) half-life times of Cf isotopes find nice agreement with the experimental data, except for 2 5 6 Cf nucleus. Within the PCM, the hydrodynamical mass transfer among the outgoing binary fragments occurs through a cylindrical vessel connecting them. For the overlapping configuration (R < R T ), the two classical models namely Model A and Model B (differ in the way the radius of the connecting cylinder is controlled) are used to estimate mass transfer flow of binary fragmentation. It is observed that with change in the overlapping distance, the radius of the cylindrical vessel changes in Model A, whereas the same remains fixed in Model B. In case of Model B, the effect of cylindrical radii parameter ( α c ) is also analyzed for 2 3 7 − 2 5 6 Cf parents at optimum neck-length (Δ R) in view of different observable such as most probable SF fragments, preformation probability, mass transfer, the SF half-lives and the results are compared with Model A calculations. The magnitude of mass transfer, preformation probability, and hence the SF half-lives gets significantly modified on switching from Model A to Model B. Further, a large amount of mass is transferred between the asymmetric fragments as compared to the symmetric ones. The SF half-lives are shown to depend strongly on the choice of classical models as well as on the cylindrical radius parameter, α c . The study infers the importance of classical models to spread further light in the understanding of the dynamical behavior of fragment formation in the fission process. [ABSTRACT FROM AUTHOR]

The current study aimed to examine dissipation dynamics of cypermethrin, emamectin benzoate, and indoxacarb insecticides in different parts of amaranth (Amaranthus tricolor L) and mustard greens (Brassica juncea) and determine their half-lives for a safe harvest. Two experiments, one in the open-field and one in a net-house were set up to grow the two crops; the three insecticides were applied 20 days after transplanting. Different crop parts (leaves, stem, and root) were collected after 2 hours, 2, 4, 6, 8, and 10 days after the insecticide application for measurements of their residue using GCMS/MS (cypermethrin and indoxacarb) and LC-MS/MS (emamectin benzoate). Results showed that dissipation dynamics of the pesticides fitted well to the pseudo-first-order kinetics model with three parameters. The pesticide's half-lives were significantly dependent on the crop types and crop parts. The half-lives of cypermethrin varied from 3.0 - 5.3 days; the half-lives of emamectin benzoate were from 0.37 - 0.64 days, and those of indoxacarb were from 12.5 - 13.5 hours. The highest half-lives were in the stem part. The open-field conditions resulted in shorter half-lives than the net-house condition. Based on the Codex Maximum Residue Limit, harvesting the leaves of amaranth and mustard greens in the open-field condition should not be carried out until after 7.7 and 7.1 days respectively from the last application of cypermethrin and after 1.4 and 1.3 days of emamectin benzoate. In the net-house condition, the harvest of the leaves of amaranth and mustard greens could be implemented after 9.4 and 7.8 days for cypermethrin and after 1.8 and 1.4 days for emamectin benzoate, respectively. Meanwhile, it could be safe to harvest the leaf part of the two tested crops after 12 hours from the last application of indoxacarb. [ABSTRACT FROM AUTHOR]

This paper studies asymmetric dynamics of real GDP growth by estimating linear and nonlinear quantile persistence over different parts of the conditional distribution for six major developed economies. Several novel quantile-based hypotheses are motivated in this paper and tested for the steepness asymmetry of real GDP growth that hypothesizes that contractions are steeper than expansions. The empirical results show that quantile persistence is generally high at far lower tails, thus requiring much longer half-lives to reverting negative deviations to the mean of real GDP growth and hence leading to gradual economic recoveries. By contrast, less persistence in far upper tails tends to generate sharp and short economic downturns that adjust positive deviations towards the mean of real GDP growth so as to cause abrupt economic recessions. In particular, this asymmetry in quantile persistence strongly supports the steepness asymmetry conjecture, robust to the presence of structural breaks and potential nonlinearities in real GDP growth. [ABSTRACT FROM AUTHOR]

The IUPAC-IUGS joint Task Group "Isotopes in Geosciences" recommends a value of (106.25 ± 0.38) Ga for the half-life of 147Sm, and a corresponding decay constant λ 147 = (6.524 ± 0.024) × 10−12 a−1, both with a coverage factor k = 2. For the extinct radionuclide 146Sm two very different half-lives are used in the scientific community (c. 68 and 103 Ma), to such a degree that no consensus value can be endorsed at present by the Task Group. Pending dedicated re-investigations it is recommended that papers using the 146Sm decay to quantify the cosmo/geological evolution of (extra)terrestrial samples perform a twin set of calculations using both proposed half-lives. [ABSTRACT FROM AUTHOR]

Pyraoxystrobin is a methoxyacrylic fungicide with low toxicity, high efficiency and broad spectrum. It has good control effect on rice blast, rice sheath blight, cucumber downy mildew and cucumber powdery mildew. In order to explo re the degradation characteristics of pyraoxystrobin in water, the hydrolysis dynamics of pyrao xystrobin at different temperatures, pH values and t he photolysis dynamics under different illumination were studied, the hydrolysis and phot olysis prod ucts and pathways of pyraoxystrobin wer e studied by mass spectrometry with 13 C-pyraoxystrobin as control. The test results showed t hat the Pyraoxystrobin was difficult to hydrolyze in acidic and alkalescent aqueous solution (pH 8. 0). In alkaline aqueous solution (pH 10. 0-13. 0), t he hydrolysis dynamics of pyraoxystro bin was affected by temperature. With t he increase of temperature and pH values, the degradation rate was accelerated. The hydrolysis rate constants were linearly positively correlated with the pH values. Hydrolysis reaction was base-catalyzed reaction, and the higher temperatures, was the higher rate constants of base catalytic reaction were. Under indoor simulated sunlight and 30 °C, pyraoxystrobin was easy to photolysis, and t he photolysis reaction rate was increased with light intensity and ultraviolet intensity. Pyraoxystro bin was difficult to photolyze under the outdoor natural light at 13-19 °C . It was speculated that the ester bond was broken on the unlabeled atom C and an alkyl group (CH3) was removed in the hydrolysis process of pyraoxystrobin. The product might be (E)-2-[ 2-[[ 3-(4-chlorophenyl)-1-methyl-l H-pyrazol-5-oxy] methyl] phenyl]-3-methoxyacrylic acid (C21 H 19 ClN2 O4). The photolysis products was presumed to be 3-(4-chlo rophenyl)-5-((2-(4-methoxyfuran-3-yl) benzyl) oxy)-1-met hyl-l H-pyrazole after car bonyl hydrogenation on unlabeled atom C, dehydration and ring formation. The hydrolysis and photolysis products of zolexin ester and 13C-pyraoxystro bin ester were analyzed by mass spectrometry. It was speculated that the hyd rolysis process of zolexin ester may be the breaking of ester bond on unmarked C atom and the dehydration of an alkyl group to form C21 H19 ClN2 0 4. The photolysis process may be carbonyl hydrogenation and dehydration on unmarked C atom. After cyclization, 3-(4-chlorophenyl)-5-[[ 2-(4-methoxyfuran-3-phenyl] methoxy]-1-methyl-l H-pyrazole (C22 H 19 ClN2 O3) was formed. In this study, 13C-labelled pyraoxystrobin was used as internal standard, the degradation dynamics of zoxomycin in water were researched at different pH values and temperatures, and the photolysis of zoxomycin in water were researched under different light conditions. The hydrolysis and photolysis products and pathways of zoxomycin were analyzed and speculated in order to provide data for rational drug use, water source protection, ecological balance maintenance and food safety. [ABSTRACT FROM AUTHOR]

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It was recognized that the magic numbers of nuclei 2, 20, 28, 50, 82 and 126 are predicted to be more stable than the neighbor nuclei. Later on the researchers predicted that the magic numbers for protons are 114, 122, 124 and 164 and the magic numbers for neutrons are 184, 196, 236 and 318. The predicted second generation magic number for proton and neutron comes in the superheavy nuclei region. The superheavy nuclei with magic number of protons/neutrons are 2 9 8 114, 3 1 0 114, 3 0 6 122, 3 1 8 122, 3 0 8 124, 3 1 0 124, 3 1 0 126 and 3 2 2 126. All the possible decay modes have been studied by using three different models such as modified generalized liquid drop model, dynamical cluster model and coulomb-proximity potential model. In the second part of this study, we have made detailed investigations to synthesize the above said nuclei using fusion reactions with modified Woods–Saxon potential model. This study also identifies the most possible projectile target combinations for the synthesis of the predicted magic nuclei in the superheavy nuclei region. [ABSTRACT FROM AUTHOR]

The phenomenon of proton emission from nuclear ground states limits the possibilities of the creation of more exotic proton rich nuclei that are usually produced by fusion-evaporation nuclear reactions. In the energy domain of radioactivity, proton can be considered as a point charge having highest probability of being present in the parent nucleus. Conclaves et al.1 studied the two-proton radioactivity of nuclei of mass number A<70 using the effective liquid drop model. Delion et al.2 reviewed the theories of proton emission to analyse the properties of nuclear matter. Maglione et al.3 analysed the proton emission from the some deformed nuclei. We have studied proton decay in almost all actinide nuclei. We have calculated the energy released during the proton decay (QP), penetration factor (P), and half-lives of proton decay. Proton decay half-lives are also longer than that of other decay modes such as alpha decay and spontaneous fission. To check the Geiger- Nuttal law for proton decay in actinide nuclei, we have plotted the logarithmic proton decay half-lives versus 1/sqrt(Q). The competition of proton decay with different decay modes such as alpha decay and spontaneous fission are also studied. We have also highlighted possible proton emitters with the corresponding energies and half-lives in the actinide region. [ABSTRACT FROM AUTHOR]

Photonuclear reactions have great importance in understanding the structure of the nuclei. These reactions, performed using the gamma rays obtained by way of bremsstrahlung, are a standard nuclear physics experiment. In this study, a non-enriched barium sample was activated for the first time by using a clinical linear accelerator (cLINACs). The spectrum of barium radioisotopes was obtained by using a gamma spectrometry with a high purity germanium (HPGe) detector. The obtained spectroscopic data were analyzed and energy levels and half-life values together with their uncertainties were obtained. Some energy levels and half-lives of 1 2 9 Ba were determined with more precision than those of literature values. [ABSTRACT FROM AUTHOR]

The cereal leaf beetle (CLB), Oulema melanopus L. (Coleoptera: Chrysomelidae), is a major pest of cereal crops that has recently been reported in western Canada. We developed a set of primers to detect CLB DNA in the gut of six common predator taxa in wheat fields: lady beetles (20 positives of 143 individuals), nabid bugs (73 positives of 206 individuals), and wolf spiders (2 positives of 25 individuals). Nabis americoferus Carayon (Hemiptera: Nabidae) and Coccinella septempunctata L. (Coleoptera: Coccinellidae) were the most abundant predators in cereal fields, with 0.35 and 0.05 proportion of samples positive for CLB DNA, respectively. The prey DNA half‐lives were used to adjust the estimates for N. americoferus to 0.22, due to its longer DNA detectability relative to C. septempunctata. Overall, Hippodamia parenthesis (Say) (Coleoptera: Coccinellidae) had the highest proportion of positives at 0.43. There was a positive association between CLB abundance and proportion of N. americoferus and C. septempunctata positives for CLB DNA. This study highlights the contribution of generalist predators to CLB mortality and their important role in integrated management for CLB. Furthermore, we provide a molecular tool that can be used to identify predators of CLB and predation frequency in agricultural fields. [ABSTRACT FROM AUTHOR]

We have predicted possible isotopes for Z = 116 by studying the competition between different decay modes such as binary, ternary, cluster radioactivity, and alpha decay. The spontaneous fission is a dominant decay mode for 274-276Lv and 295-339Lv; alpha decay is a prominent decay mode for the nuclei 277-294Lv. In the second part, we have identified the most possible projectile-target combinations to synthesize the superheavy nuclei with Z = 116. We have also identified the most suitable projectile-target combinations to form compound nucleus with Z = 116 which are 36Ar + 248Cf, 36Ar + 249Cf, 36Ar + 250Cf, 36Ar + 251Cf, 36Ar + 252Cf, 36Ar + 253Cf, 37Ar + 253Cf, 38Ar + 253Cf, 39Ar + 253Cf, 40K + 253Bk and, 40K + 254Bk. We also identified the most probable spontaneous fission fragments after alpha decay chains of 284-294Lv. [ABSTRACT FROM AUTHOR]

The Gamow's theory of alpha decay is used to systematically compute the alpha decay half-lives of even-even isotopes between the atomic numbers Z = 62 and Z = 118. The computation of the alpha decay half-lives of the parent nuclei are done by considering the experimental decay energies (Q) and the penetration frequency (n). These values are compared with experimentally available data and it is found to be in good agreement with the same. The explanation for the obtained patterns of variation of alpha decay half-lives as a function of neutron numbers for the whole region 62 ≤ Z ≤ 118 is given by the nuclear shell effect. This computational work proves that the Gamow's theory still holds good for the explanation of the half-lives of alpha emitters. [ABSTRACT FROM AUTHOR]