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The present study focusses on the shielding parameters (X-ray and gamma radiation) such as mass attenuation coefficient (MAC), linear attenuation coefficient (LAC), Tenth Value Layer (TVL), Half Value Layer (HVL), electron density, effective atomic number, specific gamma ray constant and radiation protection efficiency in some iron boron alloys such as Fe0.95B0.05 (A), Fe0.9B0.1 (B), Fe0.8B0.2 (C), Fe0.7B0.3 (D), Fe0.6B0.4 (E) and Fe0.5B0.5 (F). We also investigated the neutron shielding properties (NSP) such as coherent and incoherent neutron scattering length and cross section. Then the total neutron scattering and absorption cross sections were evaluated along with the radiation protection efficiency in the iron boron alloys. The shielding properties of the various iron boron alloys were compared. It is clear from the detailed study that the iron boron alloy Fe0.95B0.05 is a perfect absorber for x-ray, gamma and neutron radiation. We therefore suggest that the iron boron alloy Fe0.95B0.05 is a good shielding material for gamma, neutrons and x-rays.

Many microscopic and macroscopic models are available in the literature to study the cluster radioactivity. The investigation of appropriate theoretical model to study the cluster decay process is an important aspect. We studied cluster-decay in the atomic and mass number range [Formula: see text] and [Formula: see text] using modified generalized liquid drop model (MGLDM), Coulomb and proximity potential model (CPPM) and generalized liquid drop model (GLDM). The results obtained using macroscopic models are compared with that of microscopic models. There are various mass excess tables available in the literature. But indentification of suitable mass excess table for cluster radioactivity is an also important part of this study. The macroscopic models, such as MGLDM, CPPM and GLDM, were used to analyze cluster-decay half-lives. Along with this, microscopic and semi-empirical relations were also investigated. The standard deviation is evaluated in macroscopic, microscopic and semi-empirical formulae. A detailed investigation shows that among macroscopic model-MGLDM, macroscopic-RMFM and in case of semi-empirical formulae, AZF produces less deviation. Hence, these results give an insight into prediction of cluster decay half-lives in heavy and superheavy region for unknown nuclei.

Objectives: To calculate the optical and structural parameters of the copper sodium tartrate (CuNaT) crystal for investigating its usefulness in the non-linear optics, it was analyzed by XRD and optical studies. Methods : A good nonlinear optical CuNaT crystal was grown by silica gel medium. The fundamental factors to prepare the silica gel for the controlled and defect - free growth of the CuNaT crystal are gel pH, gel density and gel setting period. Findings:The non-centro symmetric structure with refined lattice parameters: a = 7.7230 A, b = 20.2964 A, c = 7.9896 A and the required functional groups: O-H, M-O,C-O and C=O bonds of CuNaT were recognized by the XRD and FTIR studies. Novelty: The monoclinic structure and space group P21 of grown CuNaT crystal was non-identical to the orthorhombic structure of the copper tartrate crystal was enabled to identify its novel structure. The NLO competence of the CuNaT was 0.38 times relative to KDP and of higher LDT value than the KDP, provided its novel optical properties. Applications: The strong intensity emission peaks recorded at 297 nm and 380 nm in the photoluminescence spectrum and the lower absorption edge at 334 nm in the UV spectrum of the CuNaT crystal exhibited its potential use in non-linear optics. Keywords: Single crystal XRD; FTIR; UVVisNIR; PL; SHG; LDT

Cluster radioactivity is an intermediate between alpha decay and spontaneous fission. It is also an exotic decay obtained in superheavy nuclei. When a cluster decay is detected in superheavy nuclei, the daughter nuclei is having near or equal to doubly magic nuclei. We have investigated cluster decay of isotopes of He, Li, Be, Ne, N, Mg, Si, P, S, Cl, Ar and Ca in the superhaevy nuclei region 299-306122. We have also compared the logarithmic half-lives of cluster decay with that of other models such as Univ [1], NRDX [2], UDL [3] and Horoi [4]. From this study it is concluded that cluster decay of 4He, 22Ne, 26Mg, 28Si 30Si, 34S, 40Ca and 46Ca are having shorter logarithmic half-lives compared to exotic cluster decay modes.

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 [Formula: see text] 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 [Formula: see text]. This study is useful in the understanding of superheavy element nuclei structure.

A detailed investigation of different decay modes, namely alpha decay, beta decay, cluster decay, including heavy particle emission ( $$Z_{c}>28$$ ), and spontaneous fission, was carried out, leading to the identification of new cluster and beta-plus emitters in superheavy nuclei with $$104 \le Z \le 126$$ . For the first time, we identified around 20 beta-plus emitters in superheavy nuclei. Heavy-particle radioactivity was observed in superheavy elements of atomic number in the range $$116\le Z \le 126$$ . $$^{292-293}$$ Og were identified as $$^{86}$$ Kr emitters, and $$^{298}122$$ and $$^{300}122$$ were identified as $$^{94}$$ Zr emitters, whereas heavy-particle radioactivity from $$^{91}$$ Y was also observed in $$^{299}123$$ . Furthermore, the nuclei $$^{300}124$$ and $$^{306}126$$ exhibit $$^{96}$$ Mo radioactivity. The reported regions of beta-plus and heavy-particle radioactivity for superheavy nuclei are stronger than those for alpha decay. The identified decay modes for superheavy nuclei are presented in a chart. This study is intended to serve as a reference for identifying possible decay modes in the superheavy region.

A new copper (II) sodium (I) tartrate trihydrate with general formula of [(Na2 Cu2 (C4H4O6) 3 (H2O) 3) 3H2O] (NaCuT) was synthesized and grown from the silica gel. The monoclinic structure and the space group P21 of the as-grown crystal are calculated and non identical with copper tartrate is found by the single crystal and powder X-ray diffraction studies. The presence of O H, C O, C O, C H and M O bonds were confirmed by Raman FTIR spectroscopy. The UV spectrum showed the transmittance in the Ultra-Violet region about the lower cutoff wavelength at 310.5 nm which makes the material to be suitable for UV filters. Different decomposition stages with respect to the mass loss of the copper sodium tartrate were studied by thermo gravimetric analysis. Occurrence of the improved electrical conductivity by the pi electrons of the C O and O-H----O groups of the CuNaT crystal was established by the dielectric studies. From Z-scan studies, the present sample proved its suitability for non linear optical applications.

The present work used eight different proximity functions in the modified liquid drop model [MGLDM] to study the cluster and alpha decay half-lives in the superheavy nuclei Z = 120. The values produced by the present work are compared with experiments. We have explored the proximity function is suitable in MGLDM for the cluster and alpha radioactivity of superheavy nuclei. The present work is useful in the study of decay modes of superheavy nuclei Z = 120.

The concept of heavy particle radioactivity is studied using modified generalised liquid drop model (MGLDM) in the superheavy element Z = 126. The eight different proximity functions and different mass excess values were used to evaluate cluster/HPR. The logarithmic half-lives using different proximity functions and mass excess values are compared with that of experiments. The HPR of 60Ni to 102Ru have been studied in the superheavy region 126 306 to 126 326 . The HPR half-lives has been compared with the different decay modes such as α-decay, β-decay and spontaneous fission. 9 HPR emitters, 4 α emitters, 1 β + emitter and 7 spontaneous fission nuclei were identified in the superheavy nuclei 126 306 − 314 , 126 315 − 318 , 126 319 and 126 320 − 326 respectively.

Optical quality single crystals of ethylenediaminium (2,4-dinitrophenolate) [EDA(2,4)DNP] were grown by solvent evaporation method for optical limiting applications against intense ultrashot pulse lasers. Single crystal XRD showed that the material crystallizes in monoclinic system with centric space group P 2 1 / C . The crystal packing diagram was elucidated for the first time in literature and it revealed six hydrogen bonds played a very important role in stabilizing the structure. A bifurcated hydrogen bond was also observed between ethylenediamminium and dinitrophenolate ions. The formation of charge transfer complex during the reaction of ethylenediamine and 2,4-dinitrophenol was strongly evident through the vibrational spectroscopic studies. TG–DTA and DSC curves indicate that the material exhibited strong decomposition at 224 °C. Ground state absorption analysis showed that the grown crystals possess absorption maxima in UV region (270 nm, 346 nm) and wide optical transmittance window (480–1200 nm) in the entire visible and NIR region. Measurement of two photon absorption (2PA) and optical limiting response by Z-scan technique under nanosecond pulse excitation was reported. Hence EDA(2,4)DNP with high 2PA coefficient (0.79 ± 0.04 × 10 −10 m/W) and low limiting threshold (2.40 ± 0.05 × 10 12 W/m 2 ) will be a potential candidate for optical limiting applications like eye and sensor protection against short pulse lasers that are well spread in human interactive sectors.

The newly synthesized CdNa2?2C2O4?2H2O crystals having a size of 0.30 × 0.25 × 0.20 mm3 were grown by the single-diffusion reaction method in the silica gel medium at 28?C temperature. The crystalline nature of crystals was determined in 20 days by 1) varying the concentrations of the feed solutions and the gel pH level, 2) changing the specific gravity of the feed solution, and 3) changing the gel aging period. The crystals were characterized by using the methods such as powder X-ray diffraction, FTIR, UV, SEM-EDAX, TGA/DTA, and micro-hardness test. The structure of as-grown crystals was determined by the powder crystal XRD patterns. FTIR & SEM-EDAX spectral analyses were used to confirm the presence of the required functional groups of as grown crystals. UV absorption spectrum, the absorption peaks at 224.64 nanometer, determined the energy gap. TGA/DTA thermo gram was used to detect the thermal stability of sodium mixed cadmium oxalate dihydrate crystals. The present grown crystals were brittle and also plastic in nature was identified by Vickers micro-hardness test.

Nonlinear optical single crystal of L-Proline trichloroacetate (L-PTCA) was successfully grown by Slow Evaporation Solution Technique (SEST). The grown crystals were subjected to single crystal X-ray diffraction analysis to confirm the structure. From the single crystal XRD data, solid state parameters were determined for the grown crystal. The crystalline perfection has been evaluated using high resolution X-ray diffractometer. The frequencies of various functional groups were identified from FTIR spectral analysis. The percentage of transmittance was obtained from UV Visible spectral analysis. TGA-DSC measurements indicate the thermal stability of the crystal. The dielectric constant, dielectric loss and ac conductivity were measured by the impedance analyzer. The DC conductivity was calculated by the cole-cole plot method.

Gamma bis glycinium oxalate (GBGOx) crystal was synthesized and grown by slow evaporation solution technique. The structure of pure GBGOx crystal has been examined by single crystal X-ray diffraction analysis. The confirmation with single crystal XRD reveals that the crystal belongs to monoclinic system with space group C 2 . The FTIR spectrum was recorded to identify the expected functional groups. UV–vis-spectrum shows the lower cut off wavelength and 80% of transmittance in the UV–vis region. The photoluminescence measurement shows that the material is suitable for photonic devices. Preliminary measurement of green light emission using Kurtz powder technique indicates that their second harmonic generation (SHG) efficiency. The microhardness analysis revealed that the grown crystal belongs to soft material category. The encouraging results show that the GBGOx crystals have great potential applications in optical devices.

We have studied the X-ray and gamma radiation shielding parameters such as mass attenuation coefficient, linear attenuation coefficient, half value layer, tenth value layer, effective atomic numbers, exposure buildup factors and specific gamma ray constant in aluminum silicon alloys (Al-47, Al– 32S, Al-43, Fe–Si, Al-356, Al-355 and Al-A355). We have also studied the neutron shielding properties such as coherent neutron scattering length, incoherent neutron scattering lengths, coherent neutron scattering cross section, incoherent neutron scattering cross sections, total neutron scattering cross section and neutron absorption cross sections in aluminium silicon alloys. It has been compared the shielding properties among the studied aluminium silicon alloys. From the detail study it is found that mean free path, HVL and TVL is minimum and exposure buildup factor is maximum for ferro-silicon alloy. Hence it is clear that ferro-silicon alloy is good absorber for X-ray and gamma radiation. The attenuation parameters for neutron are large for ferro silicon alloy. Hence, we suggest ferro silicon alloy is the best shielding materials for X-ray, gamma and neutrons.

Single crystal of l -alanine cadmium chloride (LACC) has been grown by the conventional seed suspended technique. The grown crystals were subjected to various characterizations such as powder XRD, FTIR, UV–vis, second and third harmonic generation measurements. The structure of pure LACC crystal has been examined by powder X-ray diffraction analysis. The confirmation with single crystal XRD reveals that the crystal belongs to monoclinic system with space group C 2 . The FTIR spectrum was recorded to identify the expected functional groups and the molecular structure was confirmed by 1 H NMR spectrum. Dielectric measurements reveal that the grown crystals have very low dielectric loss. UV–vis-spectrum shows the lower cut off wavelength at 245 nm and transparency above 95% in the UV–vis region. The optical band gap was determined to be 5.12 eV. Preliminary measurement of green light emission using Kurtz powder technique indicates that their second harmonic generation (SHG) efficiency. The third order nonlinear optical parameters such as nonlinear refractive index ( n 2 ), nonlinear absorption coefficient ( β ) and third order susceptibility ( χ 3 ) are found to be in the order of 2.4233 × 10 −14 cm 2 /W, 0.2252 × 10 −4 cm/W, 0.9134 × 10 −15 esu, respectively by Z scan measurement. The encouraging results show that the LACC crystals have great potential applications in optical devices.

A nonlinear optical 3-hydroxy anthranilic acid (3-HAA) is synthesized, and a single crystal is grown by slow evaporation method. The structural perfection of the grown crystal is predicted by the powder X-ray diffraction (XRD) analysis. The presence of functional group is confirmed by Fourier transform infrared (FTIR) spectroscopy. The dielectric behavior of the grown crystal is analyzed for different frequencies for the temperature range 40–150°C.

The crystal lattice plays an essential role in the charge density wave (CDW) phase transition together with the electron system through electron–phonon interactions. The CDW in the layered compound 1T-TaS 2 at low temperatures has a commensurate phase, which causes superlattice points to appear in the Brillouin zone of the undistorted phase. Since the effect of CDWs is to directly modulate the lattice, it is evident that an investigation that looks directly at the phonon frequencies would be most instructive in examining this phenomenon. Hence the Born–von Karman formalism, in which the equilibrium conditions are fulfilled, has been employed for the calculation of phonon frequency distribution curves of 1T-TaS 2 both in the normal and in the commensurate charge density wave (CCDW) phases. A folding technique has been adopted for the calculation in the CCDW phase. The phonon distribution and some dominant phonon frequencies for both the phases have been reported. With these results the thermal properties such as specific heat capacity, Debye Waller factor and thermal conductivity have been worked out, and are compared with the available experimental results.

2-Amino-5-nitropyridinium halides (2A5NPBr)/(2A5NPCl) were synthesized by dissolving 2-amino-5-nitropyridine in hydrobromic/hydrochloric acid. Nanoparticles of 2A5NPBr and 2A5NPCl were attained by hydrothermal method. For comparison and estimation of mechanical properties, single crystals of the samples were grown by slow evaporation process. SEM analysis shows the formation of nanoparticles of 2A5NPBr and 2A5NPCl with average grain size of 50 and 100[Formula: see text]nm, respectively. UV-Vis analysis reveals that the materials possess low cut-off wavelength and a wide optical transmission window. By Vickers test, the Meyer index (n) was estimated to be 1.33 for 2A5NPBr and 2.49 for 2A5NPCl crystals. The SHG efficiency of 2A5NPBr and 2A5NPCl nanoparticles was calculated to be 1.5 and 4.3 times that of well known NLO material KDP. The role of cations in demonstrating the desired NLO properties were discussed in detail.

Lattice dynamical investigation on the Ni0.3Fe0.7-H system has been carried out to calculate the phonon dispersion for Fe rich Ni-Fe alloy along the [100], [101] and [111] directions. A reasonably good agreement is found between the computed and experimental results. Phonon density of states, specific heat and the Debye temperature are also calculated and the results are compared with the available results of others. The mean square displacement of atoms surrounding the interstitial hydrogen atom and the defect modes are also reported.

The charge density wave (CDW) in the layered compound 2H-TaSe 2 at low temperatures has a commensurate phase, which causes super lattice points to appear in the Brillöuin zone of the undistorted phase. A Born-von Karman formalism has been employed for the calculation of phonon frequency distribution curves of 2H-TaSe 2 both in the normal and in the commensurate charge density wave (CCDW) phases. A folding technique has been adopted for the calculation in the CCDW phase. The phonon distribution for both the phases have been reported. With these distributions the thermal properties such as specific heat capacity, Debye Waller factor W(k) and thermal conductivity have been worked out, and compared with the available experimental results.

The Charge Density Wave (CDW) in the layered compound 1T-TaSe 2 at low temperatures has a commensurate phase which causes superlattice points to appear in the Brillouin zone of the undistorted phase. The phonon frequency distribution of this system for both the normal and the Commensurate Charge Density Wave (CCDW) phases have been worked out theoretically using the Born-von Karmann formalism. With these results the thermal properties such as specific heat capacity, Debye-Waller factor and thermal conductivity have been worked out and are compared with the available experimental results.

This paper gives a vivid picture about Aluminium matrix composite. P/M aluminium and aluminium matrix composites offer lower density, improved strength, stiffness, and wear resistance. The materials are produced from both blended elemental powders and pre alloyed powders with additives by a range of processing routes such as sintering, compression and annealing. The purpose of the investigation is to study the characteristics of selected Al-Cu composition. Because aluminium is silvery–white in colour and extensively used where a light non corrosive metal is desired as an aircraft and automobile components where the saving of weight is an added advantage and moreover Aluminium finds its widest use when alloyed with small amount of other metals.

ZnS‐MgS nanocomposites was successfully prepared by the microwave assisted solvothermal method using a domestic microwave oven. The prepared sample was annealed at 100 °C for 1 hr to improve the ordering. Grain sizes and lattice parameters were determined by carrying out X‐ray powder diffraction measurements. Scanning electron microscopy (SEM) shows the morphology. AC electrical measurements were carried out on pelletised samples at various temperatures ranging from 40–150 °C. Results of the present study reveal that the space charge contribution plays a significant role in the charge transport process and polarizability.

In the title compounds, 4-aminopyridinium 4-aminobenzoate dihydrate, C(7)H(6)NO(2)(-).C(5)H(7)N(2)(+).2H(2)O, (I), and 4-aminopyridinium nicotinate, C(5)H(7)N(2)(+).C(6)H(4)NO(2)(-), (II), the aromatic N atoms of the 4-aminopyridinium cations are protonated. In (I), the asymmetric unit is composed of two 4-aminopyridinium cations, two 4-aminobenzoate anions and four water molecules, and the compound crystallizes in a noncentrosymmetric space group. The two sets of independent molecules of (I) are related by a centre of symmetry which is not part of the space group. In (I), the protonated pyridinium ring H atoms are involved in bifurcated hydrogen bonding with carboxylate O atoms to form an R(1)(2)(4) ring motif. The water molecules link the ions to form a two-dimensional network along the (101) plane. In (II), an intramolecular bifurcated hydrogen bond generates an R(1)(2)(4) ring motif and inter-ion hydrogen bonding generates an R(4)(2)(16) ring motif. The packing of adduct (II) is consolidated via N-H...O and N-H...N hydrogen bonds to form a two-dimensional network along the (102) plane.

In the title compound, [Ni(2)(CO(3))(C(5)H(6)N(2))(8)(H(2)O)]Cl(2)·5H(2)O, one of the the Ni(II) ions is six-coordinated in a distorted octa-hedral geometry, with the equatorial plane defined by four pyridine N atoms from four amino-pyridine ligands, the axial positions being occupied by one water O and a carbonate O atom. The other Ni(II) ion is also six-coordinated, by four other pyridine N atoms from four other amino-pyridine ligands and two carbonate O atoms to complete a distorted octa-hedral geometry. In the crystal structure, mol-ecules are linked into an infinite three-dimensional network by O-H⋯O, N-H⋯Cl, N-H⋯O, O-H⋯N, C-H⋯O, C-H⋯N and C/N-H⋯π inter-actions involving the pyridine rings.