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Internal conversion electron and gamma-ray spectroscopy measurements were carried out on the 10.551 y 133Ba electron-capture decay with our electron and gamma spectrometers—a mini-orange electron transporter paired to a Si(Li) detector and a large-volume HPGe detector, respectively. The relative and absolute gamma-ray intensities of all the nine transitions in 133Cs were determined. We also report the relative conversion intensities of eighteen conversion lines and their corresponding internal conversion coefficients (ICCs), four of which are being reported for the first time. Transition intensity balance at each energy level, showed that the measured values are self-consistent. This exhaustive dataset of gamma-ray intensities, internal conversion electron intensities and the ICCs that have low uncertainty, will be highly valuable for the purposes of energy and efficiency calibration of semiconductor gamma ray detectors and electron spectrometers.

Focal increased radiopharmaceutical uptake in a lesion results in focal Hot Spots in the scans. This can occur in benign infective or inflammatory disorders and cancerous diseases as well. Comparison between malignant and benign lesions is important. The Hot spots can be classified into benign and malignant lesions by Spatial Scintimetry or Temporal Scintimetry. Spatial Scintimetry compares the uptake in the region of interest with the adjacent tissue or the unaffected contralateral site. The quantitative indices are lesion/non lesion ratio, lesion/background activity and lesion to Bone ratio etc. The Temporal Scintimetry relies on the changes in the counts or uptake in the Hotspot lesion with reference to the dual point time of acquisition. The Hotspot in the bone scan can be classified using the quantitative index of retention ratio by Dr. V. Siva and Israel. In PET studies the focal hot spots can be differentiated into benign and malignant lesion using the dual phase PETCT evaluation using the Rong’s Retention ratio and Dr. V. Siva’s modified RRI values.

Background: Conventional magnetic spectrometers used for conversion electron detection are very cumbersome, require strong magnetic fields and the spectra have to be scanned point by point and have very low transmission. A magnetic filter using permanent magnets and an Si(Li) detector would facilitate multichannel analysis with high transmission. The mini-orange is a new type of spectrometer for conversion electrons combining a solid state Si(Li) detector with a filter of permanent magnets around a central absorber of lead.Purpose: An indigenously developed magnetic spectrometer if optimized properly would be of great use in conversion electron spectroscopy for both online and offline experiments. Methods: A Mini-Orange magnetic spectrometer made of small permanent magnets has been designed and developed indigenously and optimized for its best performance condition. The transmission curves for different energy regions are plotted using the conversion electron spectra from the standard gamma transitions from 153Gd, 169Yb and 131Ba decays. The optimized spectrometer facilitates multichannel acquisition of conversion electron spectra for precision electron spectroscopy. The system also can be used in in-beam experiments with minor modifications of the vacuum chamber.Results: The optimized spectrometer was used for precision electron spectroscopy. Experimental transmission curves are then obtained by plotting Transmission (T) against the corresponding electron energy for low energy, medium energy and a broad energy range. Out of the several experiments done the optimum settings for f and g, that resulted in this curve, is identified at f = 7.5 cm and g = 4.5 cm. Conclusions: The optimized spectrometer facilitates multichannel acquisition of conversion electron spectra for precision electron spectroscopy. The system also can be used in in-beam experiments with minor modifications of the vacuum chamber.

Background: In patients suffering from carcinoma prostate the incidence of skeletal metastases had been found to be very high. The presence of skeletal metastasis could be inferred by the multiple focal hotspots in the skeletal tissue. The metastatic nature of the hotspots could be inferred by multiple lesions, asymmetric distribution with increased tracer concentration. In the case of Solitary focal spot in the bone scan metastatic nature could not be attributed to it. The invasive biopsy procedure could only confirm or discard the metastatic involvement. A new non-invasive Scintimetric characterization and evaluation of skeletal hot spots in bone scans of carcinoma prostate patients was proposed and tested. Materials and Methods: The bone scan was done 4 and 24 hours after intravenous injection of 15 to 25 mCi of Tc99m Methylene Di-Phosponate with adequate hydration using the e-cam Siemens dual head gamma camera with e-cam whole body acquisition protocol in 75 patients with biopsy proven carcinoma prostate. Metastatic involvement was seen in 53 patients and was negative in 22. The Serum PSA levels were obtained from the Patient medical records were tabulated. The 185 focal hotspots in various sites in 34 patients were characterized using the temporal scintimetric method. Both 4 and 24 hr bone scan images were selected using the general display protocol. Then with the help of the region ratio processing protocol the 4 and 24 hr anterior and posterior images were selected separately. Maximum counts in the selected regions were then tabulated. Then the 4/24 hr Dr. V. Siva’s retention ratio was derived by dividing the 4hr counts of the focal hotspots with 24 hr counts along with the Israel’s 24/4 hr ratio as well. Similarly 4/24 hr Dr. V. Siva’s retention ratio of whole body scan total counts at 4 and 24 hr scans was also calculated. The results were compared and analysed. Results: The mean of 4/24hr Dr. V. Siva’s retention ratio was found to be 12.32 ± 3.3 and that of 24/4hr Israel’s ratio to be 0.08 ± 0.02 for Focal hot spot evaluation. The 4/24 hr Dr. V. Siva’s retention ratio was derived by dividing the total whole body counts at 4 and 24 hr whole body bone scan was 12.21 ± 2.78 which was closer to the Focal hot spot retention ratio. The Total PSA, Free PSA and the %PSA Values were 61.8, 19.2 and 26.8 in the Metastatic positive group and 34.5, 6.8 and 12.8 in the negative group respectively. Conclusion: Scintimetric characterization of the skeletal hot spots provided a non-invasive means for identifying the underlying pathology to enable proper management decisions. The 4/24hr Dr. V. Siva’s retention ratio was useful clinically because of its whole integer value, unlike the Israel’s 24/4hr ratio which was in decimal value. The utility of the scintimetric characterization in inferring the metastatic nature of the lesion was confirmed through biopsy of the site afflicted followed by histopathological examination. It can be concluded that the non-invasive quantitative scintimetric characterization of skeletal metastasis in Carcinoma Prostate patients deserves a place in the proper management protocol.

Aim: This study aims to propose the utility of Scintimetric Characterization of the tracer activity uptake in the joints afflicted by Rheumatoid arthritis in the bone scans. Materials and Methods: Three out of five patients of confirmed Rheumatoid arthritis who had bone scans for Bone and joint pains showed presence of skeletal hot spots in various joints. They were subjected to the scintimetric evaluation of the skeletal hot spots by Dr. V. Siva’s retention ratio by repeating the 24 hr delayed bone scans. The 58 skeletal hotspots seen in various joint spaces were subjected to the calculation of maximum counts in 3 hr and 24 hr bone scans. They were tabulated and 3/24 hr Dr. V. Siva’s Retention Ratio was calculated and analyzed. Results: They showed a mean of 5.91 ± 0.35 and standard error of means as 0.3496. The estimated variance was 8.8408 and the estimated standard deviation was 2.9734. For this sample size the estimated variance was 6.6306 and estimated standard deviation was 2.575 by HOJO’s modification. This was unavoidable due to very small size of the Sample population. Conclusion: Thus this study had shown that the scintimetric evaluation of the skeletal hotspots in the Rheumatoid Arthritis Patients showed a definitive benign value. This could provide a firm base line value to assess the response to treatment and progression as well.

Aim: The Scintimetric characterization principle is applied to the identification and quantification of presence of diastolic dysfunction using the gated thallium SPECT scans. The assessment and differentiation of Left Ventricular Diastolic Dysfunction is critical in the treatment of heart failure patients. Diastolic dysfunction is currently inferred primarily from E and A wave changes in m-mode echocardiographic changes at the mitral orifice. In the gated myocardial perfusion imaging from the time volume curve the Peak Flow Rate and Time to Peak Flow rate are derived and assessed for the presence and extent of diastolic dysfunction. All of these parameters represent changes in the left ventricular muscle mass caused by the underlying diastolic dysfunction.This study aims to highlight the diagnosis of Left Ventricular Diastolic Dysfunction for the first time using visual Phase image analysis in Gated Thallium SPECT Scan. The presence of inhomogeneous, irregular, and insufficient tracer accumulation in diastolic phase images compared to normal and homogeneous tracer distribution in systolic phase images is thought to indicate diastolic dysfunction. It also thrives to quantify the changes observed by calculating the S/D ratio by dividing the Systolic Counts by the diastolic counts obtained from the raw phase images. It is correlated with echocardiographic stages of the Diastolic Dysfunction. Materials and Methods: This study consists of 75 Males in the age group of 28 to 63 years with mean age of 47.9 +/- 7.8 years and 25 Females in the age range of 32 to 55 years with mean age of 49 +/- 6.8 years. After exercising the patients on a bicycle ergometer using Bruce Protocol 2 mCi of Thallum-201 was injected intravenously Gated SPECT MPI were acquired using Siemens Dual Head E-Cam Gamma Camera. The analysis was done using GATED SPECT PERFUSION ANALYSIS Protocol. The S/D ratio was calculated using the region ratio count protocol in the ICON software. Results: The discordance between the Diastolic and systolic images were found in 98/100 (98%)- Image1,2. The Echocardiographic evidence of Diastolic dysfunction as classified into Grade II and grade III using E / A ratio analysis was found in 87/100 (87%). The diabetes was seen in 16/100 (16%) and Hypertension was encountered in 63/100 (63%). The S/D ratio was 1.27 +/- 0.32 in Grade IILVDD and 1.68 +/- 0.03 Grade III LVDD. Conclusion: Finally, the utility of direct visual individual phase image analysis in the detection of Left Ventricular Diastolic Dysfunction is highlighted for the first time. The Scintimetric Characterization of the same with the help of S/D ratio has been shown to be different between stage II and stage III LVDD.

Aim: This retrospective analysis of the scintimetric characterization of the primary tumors of various cancers using the dual phase PETCT scans thrives to establish the utility of the Rong's Retention ratio and the Dr. V. Siva's modification of RRI. Methods: In the proven cases of various cancers the SUV max values were obtained in the Early and Delayed PETCT scans using the ROI method over the FDG avid primary sites. The PETCT scans were done using the GE Discovery IQ unit one and 4 hours after the I.V injection of 5 to 10 mCi of F18- FDG after overnight Fasting. The image analysis and the SUV were calculated using the Advantage 4.7 software provided by GE. Total of 19 primary sites at various locations were included and the calculated SUV max were used to arrive at the Rongs Retention Index (RRI) and Dr. V. Siva's modification of RRI. The values were tabulated and analyzed. Results: The Rong's retention ratio had a very narrow range with wide overlapping. However the Dr. V. Siva's modification of RRI showed much wider values with a definite cut off level. The statistical evaluation of the data confirm that the Dr. V. Siva's modification of RRI significantly correlates well with the Rong's Retention Index (RRI). Conclusion: It can be concluded that the scintimetric characterization of the primary tumors of various cancers is possible and might be useful in the identification of the primary malignancies.

Aim: This study aims to document the utility of Scintimetric Characterization of the Skeletal Hot Spots seen in the Bone Scans done in this referral center during 2016-2017, in differentiating metastatic and non-metastatic lesions. Materials and Methods: The study group consists of 59 patients referred for metastatic evaluation and non-specific bone complaints to our center. The whole body bone scan was done 3hrs after the intravenous injection of 15 to 25 mCi of Tc99m MDP using GE Millenium Gamma Camera. The 24hr whole body bone scan was repeated in all those who had focal hot spots in their scans and who accepted voluntarily with the consent of the referring physician. The counts in the focal hot spots at 3 and 24 hr bone scan images were calculated using the region ratio count protocol. The Dr. V. Siva’s Retention Ratio was calculated by dividing the3hr counts by the 24 hr counts in the focal hotspots. The values of metastatic and non- metastatic groups were tabulated and analyzed. Results: In our series 35/59 (59%) scans were negative and did not show any focal changes. 24/59 (41%) scans showed focal changes in the form of hot spots. Out of the total 69 hot spots analyzed 31 (45%) had the value of 13.07 ± 1.02 indicating metastatic nature and 38 (55%) had the value of 6.07 ± 0.62 confirming the benign nature of the lesions. Thus the metastatic group had the mean value which is almost twice that of the benign group. The statistical evaluation confirmed the significant difference between the two groups. Conclusion: It can be concluded that the Scintimetric characterization of the focal hot spots by Dr. V. Siva’s retention ratio effectively provides useful means to differentiate between the metastatic and non-metastatic lesions in the tertiary referral diagnostic center as well.

The mass attenuation coefficients of graphene, MWNTs and, SWNTs have been measured for gamma energy range 356 to 1332 keV from the radioactive sources 60Co, 133Ba and 137Cs using a well calibrated gamma ray spectrometer consisting of a 3 x 3 NaI(Tl) scintillation detector coupled to a PC based 8K nuclear Multi Channel Analyser (MCA). In an interesting way results showed that MWNTs had the highest values of mass attenuation coefficients indicating their potential use as the best shielding material.

The decay of 153Sm was studied with a HPGe detector and a Si(Li) detector based electron transporter. Forty four gamma transitions belonging to sixteen excited levels in the daughter nucleus 153Eu were analyzed for their energies, emission intensities, conversion electron intensities and conversion coefficients. These values have resulted in the determination of precise beta emission intensities to the levels in 153Eu and in the construction of an internally consistent decay scheme. The present study will add to the decay data available on this radionuclide for reliable dose estimations for medical applications.

GNCIA allows a sensitive and selective detection of HIV-1 infections with a sensitivity of 5 pg/ml., We have engineered streptavidin-labeled fluorescent gold nanoclusters to develop a gold nanocluster immunoassay (GNCIA) for the early and sensitive detection of HIV infection. We performed computational simulations on the mechanism of interaction between the nanoclusters and the streptavidin protein via in silico studies and showed that gold nanoclusters enhance the binding to the protein, by enhancing interaction between the Au atoms and the specific active site residues, compared to other metal nanoclusters. We also evaluated the role of glutathione conjugation in binding to gold nanoclusters with streptavidin. As proof of concept, GNCIA achieved a sensitivity limit of detection of HIV-1 p24 antigen in clinical specimens of 5 pg/ml, with a detection range up to1000 pg/ml in a linear dose-dependent manner. GNCIA demonstrated a threefold higher sensitivity and specificity compared to enzyme-linked immunosorbent assay for the detection of HIV p24 antigen. The specificity of the immunoassay was 100% when tested with plasma samples negative for HIV-1 p24 antigen and positive for viruses such as hepatitis B virus, hepatitis C virus, and dengue. GNCIA could be developed into a universal labeling technology using the relevant capture and detector antibodies for the specific detection of antigens of various pathogens in the future.

Aims and Objectives: The retrospective study of renal scans aims at analysing the renal perfusion phase curve in the DTPA scan. Four different types of perfusion phase curves for non-transplant kidney are defined and validated by comparing them with the Hilson perfusion index and Kirchner’s K/A ratio. Materials and Methods: This study consists of 36 patients comprising of 26 males with mean age of 26.17 ± 18.65 and 10 females with the mean age of 33.20 ± 11.69. Renal scans were done using Siemens dual head gamma camera. 3-5mCi 99m Tc DTPA was used and injected intravenously, images were processed to obtain the renal curve using the icon software utilizing the Gate’s formula. The perfusion curves, which form the part of renographic curves are taken for scrutiny, are classified into different types and perfusion index was calculated. Results: The perfusion phase curves were scrutinised and categorised in 4 types. These curves have been validated by using Hilson index and Kirchner’s K/A ratio. Hilson perfusion index and Kirchner’s K/A ratio shows a good correlation with the uptake phase of conventional renal curve. We observed 47.22% of Type I, 22.22% of Type II, 16.67% of Type III and 13.89% of Type IV. Conclusion: This study highlights the utility of renal perfusion phase curve analysis in the non-transplant kidney. This can also serve as a better prognostic tool in the chronic kidney disease patient. Asian Journal of Medical Sciences Vol.7(2) 2015 44-48

Mass attenuation coefficients of ten different types of wood materials were determined using gamma radiation of 1332 keV from 60Co source. Two mathematical models have been developed for the prediction of density using variation with relaxation length and half value layer of wood materials. A good agreement was observed (greater than 83%) between the measured values and the predicted model 1 and 2. Results show that Azadiracta indica has the highest relaxation length and the lowest mass attenuation coefficient, while Albizia saman has the least relaxation length and the highest mass attenuation coefficient. Results also show that Azadiracta indica has the highest half value layer and Albizia saman has the least half value layer.

In many applications, it may be desired to decompose a non-stationary signal into its individual components. If spectral components of the non-stationary signal do not overlap in the frequency domain then Fourier transform can be used to decompose the non-stationary signal. Fourier transform fails to decompose the non-stationary signal if its spectral components overlap in the frequency domain. In this study, the authors propose Fourier-Bessel transform and the time–frequency analysis in conjunction with the fractional Fourier transform (FB-TF) method for the separation of multi-component non-stationary signal whose components overlap in both time and/or frequency domains. The efficiency of the proposed method is compared with one of the traditional decomposition methods like EMD. The proposed approach is applied to both simulated and experimental radar data. Results demonstrate the effectiveness of the proposed method for non-stationary signal separation and for detecting manoeuvring target in heavy sea-clutter environments. The improvement factor and clutter attenuation are calculated and used to compare the performance of the EMD and the FB-TF methods in suppressing the sea-clutter and enhancing target detection. The proposed method can be used as a potential tool for detecting and enhancing the low observable manoeuvring air targets in the sea-clutter environment.

Wood is a complex biomaterial useful for various applications. Wood can also be used to shield radiation from nuclear sources. In the present study, the radiation effects on various wood materials of medicinal plants collected from Nallamala forest in Andhra Pradesh, India was investigated. Gamma radiation shielding characteristics such as linear attenuation coefficient, mass attenuation coefficient, half- value thickness and relaxation length of ten different types of wood materials were measured for gamma energies 511, 662, 1173, 1275 and 1332 keV from 22Na, 137Cs and 60Co radioactive sources . Measurements were performed using a gamma spectrometer consisting of NaI (Tl) scintillation detector coupled to an 8K PC based Nuclear MCA with a good geometry set up. Classification of wood and their medicinal uses also studied. Analysis of results showed an appreciable evidence of radiation attenuation, attenuation coefficient decreasing with increase of gamma en-ergy and significant variation for different species.

In this paper, we report the efficiency of the Fourier-Bessel transform (FBT) and time-frequency (TF)-based method in conjunction with the fractional Fourier transform (FrFT), for extracting micro-Doppler (m-D) radar signatures from the rotating targets. This approach comprises mainly of two processes, with the first being the decomposition of the radar return, in order to extract m-D features, and the second being the TF analysis to estimate motion parameters of the target. In order to extract m-D features from the radar signal returns, the time domain radar signal is decomposed into stationary and nonstationary components using the FBT in conjunction with the FrFT. The components are then reconstructed by applying the inverse Fourier-Bessel transform (IFBT). After the extraction of the m-D features from the target's original radar return, TF analysis is used to estimate the target's motion parameters. This proposed method is also an effective tool for detecting maneuvering air targets in strong sea clutter and is also applied to both simulated data and real-world experimental data.

A single phase of orthorhombic nano-vanadium pentoxide (V2O5) is produced using a one pot synthesis method of solution combustion process. The yellow-orange colored powder of V2O5 is obtained instantaneously by this method and has elliptical to spherical like morphology of its platelets. A majority of these particles are in the size range of less than 200 nm. As revealed by SAED this simple method of synthesis yields a highly crystalline product with monocrystalline and polycrystalline particles of V2O5 existing in the same matrix. The product shows a negative temperature coefficient of resistance (TCR) value of −3.2% °C−1 and a low hysteresis effect with temperature width of 5 °C in response to temperature variations. Such characteristics demonstrate that preparation of V2O5 by this facile method renders it a promising candidate for bolometric applications.

Atomic mass reflects the total binding energy of all nucleons in an atomic nucleus. Compilations and evaluations of atomic masses and derived quantities, such as neutron or proton separation energies, are indispensable tools for research and applications. In the last decade, the field has evolved rapidly after the advent of new production and measuring techniques for stable and unstable nuclei resulting in substantial ameliorations concerning the body of data and their precision. Here, we present a compilation of atomic masses comprising the data from the evaluation of 2003 as well as the results of new measurements performed. The relevant literature in refereed journals and reports as far as available, was scanned for the period beginning 2003 up to and including April 2012. Overall, 5750 new data points have been collected. Recommended values for the relative atomic masses have been derived and a comparison with the 2003 Atomic Mass Evaluation has been performed. This work has been carried out in collaboration with and as a contribution to the European Nuclear Structure and Decay Data Network of Evaluations.

Essential hypertension has adverse effects on both renal and heart function. There is an underlying relation between CKD (Chronic Kidney Disease) and CAD (Coronary Artery Disease).Patients with CKD has more severe CAD and prognosis of renal function is poor in patients with severe CAD. In the present study we are reporting the utility of 99mTc DTPA (diethylene triamine penta acetic acid) renogram in proving cardio renal association in a patient with AOE (angina on exertion) II, HTN (Hypertension) diagnosed with CAD by Tl-201 gated SPECT. Key-words: Essential hypertension, Coronary Artery Disease, Tc-99m DTPA renogram, Chronic Kidney Disease, cardio renal association. Key message: Tc-99m DTPA renogram successfully could identify the CKD in hypertensive patient diagnosed with CAD.

Scintimetric Characterization of the distribution of the radiotracer Tc-99m MDP in the skeletal tissues such as Spines for the early detection of metastatic spread in the cases of Prostatic Carcinoma has been carried out. Temporal Scintimetry measures the counts in the region of interest in the scans done at two time intervals 4 and 24 h. A 4/24 h, Dr. V. Siva’s retention ratio derived using Temporal Scintimetry in the characterization of skeletal hotspots in benign and malignant skeletal conditions is proposed and discussed.

Gamma emissions in the decay of 160.44 day isomer 177mLu were analyzed with a 60 cc, coaxial HPGe detector. The energies and intensities of 50 gamma transition – 40 of which belong to the daughter 177Hf, that was excited by beta decay of the isomer, and 10 to the isomeric transition in 177Lu were precisely determined. These precise values have resulted in an internally consistent decay scheme for 177mLu. These gamma intensity and gamma emission probability measurements will help in making the long lived 177mLu available as a calibration standard for HPGe detectors and also for other applications.

Complete precision electron and gamma spectroscopy measurements were undertaken for the 6.647 day decay of (177)Lu. Precision measurements of the K, L, and M internal conversion coefficients (ICCs) were made using a high transmission Mini Orange Electron Spectrometer coupled to a Si(Li) detector. We also report energies and intensities of the 6 gamma rays measured with a large volume 60 cc HPGe detector and 9 X-rays with better precision. The energies and intensities of the beta transitions from (177)Lu leading to the levels in the daughter (177)Hf were calculated by transition intensity balance at the levels.

Traditionally, Tinospora cordifolia (Willd.) Hook. F. & Thomson (Menispermaceae), Ocimum sanctum L. (Lamiaceae), Moringa oleifera Lam. (Moringaceae), and Phyllanthus niruri L. (Euphorbiaceae) are some of the commonly used medicinal plants in India for curing ailments ranging from common cold, skin diseases, and dental infections to major disorders like diabetes, hypertension, jaundice, rheumatism, etc. To understand and correlate their medicinal use, trace element studies on the aqueous extract of these medicinal plants have been carried out using particle-induced X-ray emission technique. A 2-MeV proton beam was used to identify and characterize major and minor elements namely Cl, K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, Br, and Sr in them. Results have revealed that these elements are present in varying concentrations in the selected plants. Notable results include very high concentrations of Cl, K, and Ca in all the leaf samples, appreciable levels of Mn in all plants, high Zn content in T. cordifolia, and the aqueous extract of Moringa leaves compared to others and relative higher concentrations of Cr in all the plants.

A compilation of the available experimental internal conversion coefficients (ICCs), αT, αK, αL, and ratios K/L and K/LM of high multipole (L > 2) transitions for a number of elements in the range 21 ⩽ Z ⩽ 94 is presented. Our listing of experimental data includes 194 data sets on 110 E3 transitions, 10 data sets on 6 E4 transitions, 11 data sets on 7 E5 transitions, 38 data sets on 21 M3 transitions, and 132 data sets on 68 M4 transitions. Data with less than 10% experimental uncertainty have been selected for comparison with the theoretical values of Hager and Seltzer [R.S. Hager, E.C. Seltzer, Nucl. Data Tables A 4 (1968) 1], Rosel et al. [F. Rosel, H.M. Fries, K. Alder, H.C. Pauli, At. Data Nucl. Data Tables 21 (1978) 91], and BRICC. The relative percentage deviations (%Δ) have been calculated for each of the above theories and the averages ( % Δ ¯ ) are estimated. The Band et al. [I.M. Band, M.B. Trzhaskovskaya, C.W. Nestor Jr., P.O. Tikkanen, S. Raman, At. Data Nucl. Data Tables 81 (2002) 1] tables, using the BRICC interpolation code, are seen to give theoretical ICCs closest to experimental values.

Saturable absorbers and optical limiters have contrary optical transmission properties. We report observations of simultaneous occurrence of both these effects in a nickel sulfide nanoparticle (average diameter ~5 nm) solution and a simultaneous quantitative measurement of both. Intensity-dependent nonlinear transmission studies carried out using a 7 ns Nd : YAG laser at 532 nm by the Z-scan method, revealed efficient optical limiting in nickel sulfide nanoparticle suspensions. Induced nonlinear optical scattering was identified to be the mechanism of optical limiting, and absorption at 532 nm was found to saturate. A modification of the conventional Z-scan implementation led to the retrieval of the saturation intensity, which is otherwise overshadowed by very strong nonlinear scattering.

The decay of 131 Ba to levels of 131 Cs has been studied using an HPGe detector for gamma-ray and a mini-orange electron spectrometer for conversion electron measurements. Our experiment identifies 76 gamma transitions in this decay, including 15 new gamma rays and 6 new K-conversion electron lines. The results also include M2 multipolarity assignment for the 269 keV transition, E2 assignment to two newly observed transitions, M1 + E2 for the 406 and 417 keV transitions and M3 for the 533.67 keV transition. A revised 131 Cs level scheme is proposed. While confirming the existence of 15 well-established levels, we present strong evidence from our beta decay study for five levels at 496, 764, 775, 1044 and 1258 keV which were earlier observed in reaction studies. Spin-parity assignments to a few other levels are also suggested. The level structure of 131 Cs is discussed in the light of the intermediate coupling model.

The decay of 75Se to levels of 75As has been studied using an HPGe detector for gamma-ray and a mini-orange electron spectrometer for conversion electron measurements. We identify 38 transitions in this decay, including 18 gamma rays and 16 conversion electron lines reported for the first time. New results also include E2 multipolarity assignment for the 81 keV transition, M1 assignment to three newly observed transitions and M1 + E2 for the 617 keV transition. A revised 75As level scheme is constructed using the Ritz combination principle through the computer code GTOL. While confirming the existence of 10 well-established levels, two levels at 587 and 859 keV are newly placed into the decay scheme of 75Se. The interpretation of the observed levels in terms of various theoretical approaches is briefly discussed. The newly placed 586.8 keV 1/2- and 859.9 keV 1/2+ levels are studied in the light of the Interacting Boson-Fermion Model.

The γ- and conversion electron spectra following131Ba e-decay are investigated, using HPGe detector and mini-orange electron spectrometer. Attention is particularly focussed on identifying weak transitions associated with low energy high spin levels in131Cs level scheme earlier inferred in reaction studies but not yet observed in131Ba decay. Our experiment identifies 15 new gammas and 6 new conversion lines in this decay. Internal conversion coefficients and multipolarities of several transitions are determined. Five new levels (3 with Iπ = 7/2+ and one each with Iπ 9/2+ and 11/2−) are introduced in the131Cs level scheme based on our observations taken together with the results from reaction studies. Spin-parity assignments to a few other levels are also suggested

Naproxen-Gelucire Nanoformulations (NFs) in terms of their phase solubility behavior, physico-chemical characteristics, cytotoxicity and morphology and dissolution enhancement has been studied using the poorly water soluble drug, naproxen. The NFs were prepared via wet milling using a conventional Retsch Planetary ball mill in various ratios of drug to polymer (1:1, 1:2, 1:3, 1:4). The release rate of naproxen from various ratios of drug/polymer nanoparticles was investigated using USP paddle apparatus (type II). A comparative phase solubility of naproxen was performed in different carrier concentrations of simulated gastric fluid (pH 1.2) and simulated intestinal fluid (pH 6.8). The highest dissolution enhancement was achieved for the formulation with ratio of 1:4. This is a 160% enhancement when compared to that of the pure drug. The ability of amphiphillic surfactant carriers to accelerate in vitro dissolution of poorly water-soluble drugs has been attributed to wetting, micellar solubilization, and/or deflocculation. The Korsemeyer–Peppas model most aptly fits the in vitro dissolution data and gives an insight into the possible drug release mechanisms predominated by anamolous non-Fickian diffusion. Thus, the nanoformulations studied can help improve the physicochemical characteristics of naproxen towards its dissolution enhancement and possibly will increase the oral bioavailability of the drug without any adverse cytotoxic consequences.

In this work, we report for the first time, the nonlinear optical absorption properties of antimony selenide (Sb2Se3) nanoparticles synthesized through solvothermal route. X-ray diffraction results revealed the crystalline nature of the nanoparticles. Electron microscopy studies revealed that the nanoparticles are in the range of 10 - 40 nm. Elemental analysis was performed using EDAX. By employing open aperture z-scan technique, we have evaluated the effective two-photon absorption coefficient of Sb2Se3 nanoparticles to be 5e-10 m/W at 532 nm. These nanoparticles exhibit strong intensity dependent nonlinear optical absorption and hence could be considered to have optical power limiting applications in the visible range.

A well-known limitation in the fabrication of metal-graphene composite has been the use of surfactants that strongly adsorb on the surface and reduce the performance of the catalyst. We demonstrate here a novel onepot synthesis of gold nanoparticles by laser ablation of gold strip and in-situ decoration on graphene substrate. Not only the impregnation of nanoparticles was linker free, but also the synthesis by itself was surfactant-free. The composite materials were well characterized morphologically and functionally using electron microscopy, Xray and electron diffraction, Raman spectroscopy, Zeta potential, electrochemical measurements and UV-Visible spectroscopic techniques. This linker-free gold-graphene based composite has been employed for catalytic applications pertaining to electrooxidation. We have explored the use of this composite as a binder-free electrode in electrocatalytic oxidation of methanol and ethanol in alkaline medium. Additionally, the onset potential for ethanol oxidation was found to be more negative, -100 mV, an indication of its promising application in direct ethanol fuel cells. � 2014 Wiley-VCH Verlag GmbH & Co.

The low-energy two-quasiparticle bandhead energies for the odd-odd Z=101 nucleus 250 Md are evaluated using a zero range residual neutron-proton interaction. The 250Md ground state is seen to have the spin-parity Iπ=0- corresponding to the singlet band from the configuration {p : 7/2[514]⊗n:7/2[624]} in violation of the Gallagher-Moszkowski (GM) coupling rule. The situation here is shown to be almost identical to that for the rare-earth nucleus 166 Ho , which is the only well-established exception to the GM rule known so far. Analysis of the expected low energy spectrum, including the rotational levels, for 250 Md reveals the occurrence of an as-yet-unobserved long-lived high-spin Iπ = 7- isomeric state around (80±30) keV with dominant ε and α decay modes.

The decay of 2.76y 125Sb to levels of 125Te has been studied using an HPGe detector for gamma-ray and a mini orange electron spectrometer for conversion electron measurements. We identify 38 transitions in this decay, including 13 gamma rays and 4 conversion electron lines being reported for the first time. New results also include E1 multipolarity assignments to 3 newly observed transitions and M-shell conversion coefficient for the 109 keV M4 transition. A revised 125Te level scheme is constructed using Ritz combination principle. While confirming the existence of 10 well established levels below 700 keV excitation, we introduce 3 other levels at 402.0, 538.6 and 652.9 keV. Interpretation of the observed levels in terms of various theoretical approaches is briefly discussed. The newly introduced 538.6 keV (1/2+) and 652.9 keV (3/2+) levels are seen as the two missing members of the (s 1/2 ⊗ 2+) and (d 3/2 ⊗ 2+) sextuplet in the quasiparticle-phonon coupling scheme.

The {gamma} and conversion electron spectra following the {beta} decay of {sup 147}Nd are measured using the HPGe detector and the miniorange electron spectrometer. The {sup 147}Pm level scheme comprising of 11 levels up to 686 keV excitation, interconnected by 29 transitions, is presented. The 649 keV (11) /(2) {sup {minus}} level, with six interconnecting (including two E3) transitions, is observed for the first time in decay studies. K-shell conversion coefficients for four transitions and L-shell conversion coefficients for five transitions are being reported for the first time. The I{sup {pi}}= (7) /(2) {sup +} spin-parity assignment for the 680 keV level is confirmed. Specific structure features of the {sup 147}Pm level scheme, depicting the unique coexistence of spherical shell model configurations, particle-phonon coupled multiplets, evolution of octupole collectivity, and well-developed rotational bands, are discussed; certain open questions about the spectroscopy and interpretation of the 633 and the 641 keV levels are highlighted. {copyright} {ital 1997} {ital The American Physical Society}

This paper presents new approach for detecting a maneuvering target from strong sea clutter environment, which is based on a combination of Fourier Bessel transform, fractional Fourier transform and time-frequency based method. In order to detect a maneuvering target from radar signal returns, the time domain radar signal is decomposed into stationary and non-stationary components using Fourier Bessel transform. The components are then reconstructed by applying both the fractional Fourier transform and the inverse Fourier Bessel transform. This proposed approach is applied to both simulated data and measured data. Results demonstrate the effectiveness of the proposed method for detecting maneuvering target in a heavy sea clutter.

Conversion electron and gamma spectroscopic measurements were carried out on the 160.44d 177m Lu decay with a mini-orange electron transporter coupled to a Si(Li) detector and a large-volume HPGe detector. Conversion electron intensities and internal conversion coefficients of 32 transitions in the two nuclei were obtained by the Normalized Peak to Gamma method. Of these, many are being reported for the first time. Mixing ratios were determined for the M1 + E2 transitions of the rotational bands 7/2+[404] in 177Lu , 7/2−[514] and 9/2+[624] in 177Hf populated by the isomer’s decay. The value of the rotational parameter |(g K − g R )/Q 0| was calculated for all the three bands. A revised decay scheme is proposed for 177m Lu .