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Greenstone belts are well known for gold occurrences at different regions of the world. The Dhanjori basin in the eastern Singhbhum region shows major characteristics of a rifted greenstone belt. Initially, we conducted 14 audio-magnetotelluric (AMT) measurements for a profile of ∼ 20 km in the frequency range of 1 kHz to 10 Hz over this rather complex geologic environment covering Dhanjori Volcanics (DhV) and Kolhan Group (KG). Subsequently, gravity and magnetic surveys were also conducted over this AMT profile. The purpose of the survey was to identify and map conductive features and to relate them to metallogeny of the area along with the mapping of the basement of Dhanjori basin. The strike analysis showed N30 ∘ W strike for DhV for all the frequencies and for sites over KG domain in the frequency range of 100–10 Hz, but for KG domain, the obtained strike in 1 kHz to 100 Hz is N45 ∘ E . As the combination of transverse electric (TE), transverse magnetic (TM) and tipper (Tzy) can recover the electrical signature in complex geological environment, we discuss the conductivity model obtained from TE+TM+Tzy only. The inversion was carried for the regional profile with 14 sites and for 7 sites over KG domain. Conductivity model shows two well resolved conductors, one each in KG and Quartz Pebble Conglomerate Dhanjori (QPCD) domains respectively showing common linked concordant features between these regional and KG profiles. The conductors are interpreted as sulfide mineralization linked with QPCD group of rocks which may host gold. These conductors are also horizontally disposed due to the intrusive younger Mayurbhanj Granite. These intrusives correlate well with the gravity modeling as well. The thickness of the Dhanjori basin at the central is about 3.0 km, similar to that from gravity modeling. The conductivity model also indicates the presence of shallow conductors, but could not be resolved due to lack of high frequency data. However, the results from the close-by drill site indicate the presence of shallow sulfide mineralization hosting gold. The deep level conductors delineated from AMT studies are associated with gravity high and low magnetic. ICP-AES results of Dhanjori samples show significant concentration of gold ∼ 5.0 g/t, which is of economic consideration. Thus, it can be inferred that the conductors have evidences of sulfide mineralization which host gold.

Dalma volcanics (DVs) has intruded the older Singhbhum Group of Metapelites. Despite DVs being rich in mineralisation, its boundaries are not clearly demarcated. Gravity and magnetic surveys have been attempted for mapping the boundaries in DVs. These surveys were made in the northern fringe of the DVs over an area of  ∼ 0.70  km 2 along 13 parallel lines at 50 m spacing. The data was acquired at  ∼ 25  m spacing. The surveys were taken for determination of lithological boundaries, depths and nature of causative source using Euler depth solutions and radially averaged power spectrum (RAPS). Residual anomaly maps of gravity and magnetic intensity show the same trend as that of Bouguer gravity anomaly and total magnetic intensity anomaly map indicating towards shallow sources. The magnetic map in general follows the same pattern as that of gravity anomaly maps. The map shows coincident high gravity and magnetic anomalies. These anomalies together with resistivity signatures confirm that the northern fringe of DVs hosts volcanogenic massive sulphide settings. The Euler depth solution delineated the lateral boundaries and nature of the source. It seems that the source is of spherical nature lying within a depth range of 25–40 m. The obtained lithological (vertical) units from RAPS are between Lower DVs, Upper DVs and Singhbhum Group Metapelites at depths of  ∼ 15, ∼ 25 and  ∼ 40  m , respectively. The metallogeny is associated with the Upper DVs and the corresponding delineated lithological (vertical) unit is indicative of the top of the ore body. Good agreement is observed with the geological succession from the drilling data and resistivity data. The findings suggest that the northern fringe of DVs could be a preferred target for drilling.

Magnetic and radiometric surveys were carried out over a felsic dominated rifted margin of Proterozoic volcanic terrain of a mobile belt in the eastern India. The studies were made in blocks I and II of 0.65 sq km and 0.70 sq km respectively over a previously identified conductor in the northern fringe of Dalma Volcanics (DVs). In general, both the blocks show high magnetic signature associated with sulfide mineralisation. The interpretation of magnetic data suggests that nature of the causative source is mainly horizontal cylinder in both the blocks. The depth to the top of the causative source is about 25 m in both the blocks and extends upto 60 m in block I and 40m in block II. Gamma count rate exhibits about a factor of two to three enhancements above the field background for both the blocks. The obtained iso-rad maps are similar to uranium and copper belt in the Singhbhum shear zone south of the study area. The anomalous radiometric signature of the residual soil/rock of the area indicates towards hydrothermal alteration. The detailed magnetic surveys and preliminary iso-rads results seems quite encouraging and may be attributed to VMS setting in the area and potential sulfide mineralisation with uranium mineral association in the DVs province.

CdSe nanocrystalline thin films have been synthesized on indium tin oxide (ITO) substrates by an electrodeposition technique. A Schottky junction device in the configuration, ITO/nano-CdSe/Au has been fabricated to study the device interface properties by current ( I )–voltage ( V ) and capacitance ( C )–voltage ( V ) measurements and compared with the ITO/bulk-CdSe/Au device. The I–V characteristics of the nano-CdSe device shows a series resistance effect and C–V characteristics show the presence of surface/interface traps induced by a thin native oxide layer at the nano-CdSe/Au interface and is responsible to the deviation in the ideal Mott–Schottky behavior. The presence of a thin oxide layer on the CdSe nanocrystal surface has been identified from Rutherford backscattering (RBS) spectrometry. The low frequency capacitance response of the nano-CdSe device characteristics are being compared with the bulk device, which confirms the presence of surface/interface states within the band gap of CdSe nanocrystals. Mott–Schottky plots at different frequencies indicate the formation of a Schottky barrier between nano-CdSe and Au junction.

Measuring the spin structure of protons and neutrons tests our understanding of how they arise from quarks and gluons, the fundamental building blocks of nuclear matter. At long distances the coupling constant of the strong interaction becomes large, requiring non-perturbative methods to calculate quantum chromodynamics processes, such as lattice gauge theory or effective field theories. Here we report proton spin structure measurements from scattering a polarized electron beam off polarized protons. The spin-dependent cross-sections were measured at large distances, corresponding to the region of low momentum transfer squared between 0.012 and 1.0 GeV\\(^2\\). This kinematic range provides unique tests of chiral effective field theory predictions. Our results show that a complete description of the nucleon spin remains elusive, and call for further theoretical works, e.g. in lattice quantum chromodynamics. Finally, our data extrapolated to the photon point agree with the Gerasimov-Drell-Hearn sum rule, a fundamental prediction of quantum field theory that relates the anomalous magnetic moment of the proton to its integrated spin-dependent cross-sections.

The reaction \\(\\gamma p \\rightarrow K^{+} \\Lambda(1520)\\) using photoproduction data from the CLAS \\(g12\\) experiment at Jefferson Lab is studied. The decay of \\(\\Lambda(1520)\\) into two exclusive channels, \\(\\Sigma^{+}\\pi^{-}\\) and \\(\\Sigma^{-}\\pi^{+}\\), is studied from the detected \\(K^{+}\\), \\(\\pi^{+}\\), and \\(\\pi^{-}\\) particles. A good agreement is established for the \\(\\Lambda(1520)\\) differential cross sections with the previous CLAS measurements. The differential cross sections as a function of CM angle are extended to higher photon energies. Newly added are the differential cross sections as a function of invariant 4-momentum transfer \\(t\\), which is the natural variable to use for a theoretical model based on a Regge-exchange reaction mechanism. No new \\(N^*\\) resonances decaying into the \\(K^+\\Lambda(1520)\\) final state are found.

The objective of the research described herein is to report the applicability of simple Schiff base complexes, [M(L)], where M = Ni(II), Cu(II); L =  N,N′ -ethylenebis(acetylacetoniminate), as sensing materials and indicators in qualitative, spectroscopic and volumetric determinations of acids and bases. In this regard, UV–Vis spectroscopic properties of [M(L)] in the presence of different acids (−0.25 < pKa < 5) were investigated, and acid–base titrations using these complexes as indicators were carried out. Alcoholic solutions of [Cu(L)] and [Ni(L)] are purple and orange-red, respectively, and both solutions become decolourized upon adding strong acids (pKa < 2). During this process, the intensity of the original d–d band (λ max  ~ 550 nm) decreases, and new anion-dependent CT (λ max  > 700 nm) and anion-independent CT (λ max  ~ 310 nm) bands, accompanied by three isobestic points, emerge. Addition of NaOH to the same solution, reproduces both the original colours and UV–Vis spectra, implying that the acid–base chemistry of [M(L)] is reversible. No such colour change occurs upon adding weak acids (pKa > 4), hence [M(L)] can be used as sensing materials for distinguishing strong acids from weak acids. In strong acid-weak base titrations, [M(L)] complexes are better indicators than methyl orange, as they give very sharp and clearly visible colour changes at the end point. The present paper reports, for the first time, the applicability of N,N′ -ethylenebis(acetylacetoneiminato) nickel (II) and copper (II) Schiff base complexes as acid–base indicators in strong acid-weak base titrations where the pH at the equivalence point is ~4.

There is a significant discrepancy between the values of the proton electric form factor, \\(G_E^p\\), extracted using unpolarized and polarized electron scattering. Calculations predict that small two-photon exchange (TPE) contributions can significantly affect the extraction of \\(G_E^p\\) from the unpolarized electron-proton cross sections. We determined the TPE contribution by measuring the ratio of positron-proton to electron-proton elastic scattering cross sections using a simultaneous, tertiary electron-positron beam incident on a liquid hydrogen target and detecting the scattered particles in the Jefferson Lab CLAS detector. This novel technique allowed us to cover a wide range in virtual photon polarization (\\(\\varepsilon\\)) and momentum transfer (\\(Q^2\\)) simultaneously, as well as to cancel luminosity-related systematic errors. The cross section ratio increases with decreasing \\(\\varepsilon\\) at \\(Q^2 = 1.45 \\text{ GeV}^2\\). This measurement is consistent with the size of the form factor discrepancy at \\(Q^2\\approx 1.75\\) GeV\\(^2\\) and with hadronic calculations including nucleon and \\(\\Delta\\) intermediate states, which have been shown to resolve the discrepancy up to \\(2-3\\) GeV\\(^2\\).

The atomic nucleus is composed of two different kinds of fermions, protons and neutrons. If the protons and neutrons did not interact, the Pauli exclusion principle would force the majority fermions (usually neutrons) to have a higher average momentum. Our high-energy electron scattering measurements using 12C, 27Al, 56Fe and 208Pb targets show that, even in heavy neutron-rich nuclei, short-range interactions between the fermions form correlated high-momentum neutron-proton pairs. Thus, in neutron-rich nuclei, protons have a greater probability than neutrons to have momentum greater than the Fermi momentum. This finding has implications ranging from nuclear few body systems to neutron stars and may also be observable experimentally in two-spin state, ultra-cold atomic gas systems.

We have measured the induced polarization of the \\({\\Lambda}(1116)\\) in the reaction \\(ep\\rightarrow e'K^+{\\Lambda}\\), detecting the scattered \\(e'\\) and \\(K^+\\) in the final state along with the proton from the decay \\(\\Lambda\\rightarrow p\\pi^-\\).The present study used the CEBAF Large Acceptance Spectrometer (CLAS), which allowed for a large kinematic acceptance in invariant energy \\(W\\) (\\(1.6\\leq W \\leq 2.7\\) GeV) and covered the full range of the kaon production angle at an average momentum transfer \\(Q^2=1.90\\) GeV\\(^2\\).In this experiment a 5.50 GeV electron beam was incident upon an unpolarized liquid-hydrogen target. We have mapped out the \\(W\\) and kaon production angle dependencies of the induced polarization and found striking differences from photoproduction data over most of the kinematic range studied. However, we also found that the induced polarization is essentially \\(Q^2\\) independent in our kinematic domain, suggesting that somewhere below the \\(Q^2\\) covered here there must be a strong \\(Q^2\\) dependence. Along with previously published photo- and electroproduction cross sections and polarization observables, these data are needed for the development of models, such as effective field theories, and as input to coupled-channel analyses that can provide evidence of previously unobserved \\(s\\)-channel resonances.