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| 1 | Inter-industry R&D Spillovers,Rates Of Return,and Production In High-Tech Industries显示文摘 | Jeffrey I.Bernstein M.Ishaq Nadiri | | 0，，02： | 1 |
| 2 | Petrogenesis of Middle Triassic Volcaniclastic Rocks from Balochistan,Pakistan:Implications for the Break-Up of Gondwanaland显示文摘Basaltic volcanic conglomerates near the Wulgai village in Balochistan occur in the undivided sedimentary rock unit of the Bagh complex which is the mélange zone beneath the Muslim Bagh ophiolite. The presence of Middle Triassic grey radiolarian chert within the upper and lower horizon of the conglomerates suggests that the lavas, from which these conglomerates were principally derived, were eroded and re-deposited in the Middle Triassic. The Wulgai conglomerate contains several textural and mineralogical varieties of volcanic rocks, such as porphyritic, glomerophyric, intersertal and vitrophyric basalts. The main minerals identified in these samples are augite, olivine, plagioclase(An35–78) leucite and nosean, with apatite ilmenite, magnetite and hematite occurring as accessory minerals. These rocks are mildly to strongly-alkaline with low Mg~# and low Cr, Ni and Co contents suggesting that their parent magma had undergone considerable fractionation prior to eruption. Trace element-enriched mantle-normalized patterns with marked positive Nb anomalies are consistent with 10%–15% melting of an enriched mantle source in a within-plate tectonic setting. It is proposed that this Middle Triassic intra-plate volcanism may represent mantle plume-derived melts related to the Late Triassic rifting of micro-continental blocks(including Afghan, Iran, Karakorum and Lhasa) from the northern margin of Gondwana. | Rehanul Haq Siddiqui M.Qasim Jan M.Ishaq Kakar Andrew C.Kerr Abdul Salam Khan Ehsanullah Kakar | 2017 | Journal of Earth Science2017，28，2： | 1 |
| 3 | Optimal configuration of finned annulus in a double pipe with fully developed laminar flow显示文摘 | K.S.Syed Z.Iqbal M.Ishaq | | 0，，： | 1 |
| 4 | Raising capital amid economic policy uncertainty:an empirical investigation显示文摘This paper investigates how economic policy uncertainty affects firms’frequency and their choice of financial instruments to raise capital.By applying a three-step sequential framework over a sample of 6834 publicly listed US non-financial firms,we find that during periods of high economic uncertainty,firms raise capital more frequently with a preference toward debt financing.The empirical findings suggest that firms prefer debt financing over equity financing to avoid ownership dilution and high equity premia.The rise in leverage during periods of high economic uncertainty highlights the importance of scrutinizing policy tools used to stabilize the economy during such times. | Dawood Ashraf Mohsin Khawaja M.Ishaq Bhatti | 2022 | Financial Innovation2022，8，1： | 0 |
| 5 | Nonlinear dynamical magnetosonic wave interactions and collisions in magnetized plasma显示文摘The one-dimensional nonlinear dynamical wave interactions in a system of quasineutral two-fluid plasma in a constant magnetic field are investigated.The existence of the travelling wave solutions is discussed.The modulation stability of linear waves and the modulation instability of weakly nonlinear waves are presented.Both suggest that the Korteweg-de Vries(KdV)system is modulationally stable.Besides,the wave interactions including the periodic wave interaction and the solitary wave interaction are captured and presented.It is shown that these interacting waves alternately exchange their energy during propagation.The Fourier spectrum analysis is used to depict the energy transformation between the primary and harmonic waves.It is known that the wave interactions in magnetized plasma play an important role in various processes of heating and energy transportation in space and astrophysical plasma.However,few researchers have considered such magnetohydrodynamic(MHD)wave interactions in plasma.It is expected that this work can provide additional insight into understanding of behaviors of MHD wave interactions. | M.ISHAQ Hang XU | 2020 | Applied Mathematics and Mechanics(English Edition)2020，41，8： | 0 |
| 6 | Optimization of Am-Be millicuries neutron source in a small volume cylindrical water tank for NAA显示文摘Background The neutron activation analysis(NAA)is a very powerful method for multi-element analysis of samples.NAA technique needs to be developed for low neutron flux in millicuries using the 241Am-Be neutron source.Aims To optimize sample and neutron source geometry for maximumγ-ray yield for neutron activation analysis.Method Gamma ray neutron activation analysis(NAA)has been set up where a 50-millicurie Am-Be neutron source is available.In this experimental setup,the neutron source is placed at the center of a cylindrical water tank of 40 x 40 cm in xyz plan,and thermal neutrons are produced at a distance of 1.2 cm from the source.The system is used for the activation analysis of sodium carbonate,sodium chloride and copper with the gamma ray emissions of 1.37,1.73,2.25 and 2.76 MeV for 24Na and 0.511 MeV for 64Cu having half lives of 15 hrs and 12.9 hrs,respectively.The thermal neutron activation analysis has been demonstrated by placing the samples at about 1.2 cm from the neutron source.HPGe and 3x3 inch NaI(Tl)gamma ray spectrometers have been used for the gamma ray spectrometry of these activated samples with the use of a Marinelli beaker.The geometry of the sample with respect to the neutron source has been optimized for the maximumγ-ray yield in NAA.Conclusion The geometry of the sample with respect to the neutron source has been optimized for the maximumγ-ray yield in NAA.The increase in gamma ray flux distribution in the medium of water,due to the neutron source inside the tank,has been observed by a GM detector which is due to the production of short-lived 16N on activation of 16O in water.This system can also be used for promptγ-ray analysis. | Abdul Waheed M.Ishaq Mahmood Sultan | 2019 | Radiation Detection Technology and Methods2019，3，3： | 0 |
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