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Generalized Inverses and Solutions to Equations in Rings with Involution

  • Yue Sui;Junchao Wei
    • Kyungpook Mathematical Journal
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    • 제64권1호
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    • pp.15-30
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    • 2024
  • In this paper, we focus on partial isometry elements and strongly EP elements on a ring. We construct characterizing equations such that an element which is both group invertible and MP-invertible, is a partial isometry element, or is strongly EP, exactly when these equations have a solution in a given set. In particular, an element a ∈ R# ∩ R is a partial isometry element if and only if the equation x = x(a)*a has at least one solution in {a, a#, a, a*, (a#)*, (a)*}. An element a ∈ R#∩R is a strongly EP element if and only if the equation (a)*xa = xaa has at least one solution in {a, a#, a, a*, (a#)*, (a)*}. These characterizations extend many well-known results.

Study on (n, α) reactions for the production of 51Cr, 89Sr, 99Tc, 131I, 133Xe, 137Cs and 153Sm radioisotopes used in nuclear medicine

  • Hallo M. Abdullah;Ali H. Ahmed
    • Nuclear Engineering and Technology
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    • 제55권9호
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    • pp.3352-3358
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    • 2023
  • Nuclear medicine seems to be a decent choice of medicine in the recent decade. The radioactive isotopes 51Cr, 89Sr, 99Tc, 131I, 133Xe, 137Cs and 153Sm are extremely essential in nuclear medicine. The excitation functions of the 54Fe (n, α) 51Cr, 92Zr (n, α) 89Sr, 102Rh (n, α) 99Tc, 134Cs (n, α) 131I, 136Ba (n, α) 133Xe, 140La (n, α) 137Cs and 156Gd (n, α) 153Sm reactions were calculated in this study using the EMPIRE 3.2.3 and TALYS 1.95 nuclear codes. Additionally, the cross sections at 14-15 MeV were calculated using empirical formulae and the experimental data. The computer codes were compared to the experimental data and Empirical formulas as well as the evaluated data (TENDL 2021, JENDL 3.3, JENDL 5, JEFF 3.3, EAF 2010, CENDL 3.1, CENDL 3.2, ROSFOND 2010, FENDL 3.2 b, and BROND 3.1).

SOME RESULTS ON CENTRALIZERS OF SEMIPRIME RINGS

  • ANSARI, ABU ZAID
    • Journal of Applied and Pure Mathematics
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    • 제4권3_4호
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    • pp.99-105
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    • 2022
  • The objective of this research paper is to prove that an additive mapping T from a semiprime ring R to itself will be centralizer having a suitable torsion restriction on R if it satisfy any one of the following algebraic equations (a) 2T(xnynxn) = T(xn)ynxn + xnynT(xn) (b) 3T(xnynxn) = T(xn)ynxn+xnT(yn)xn+xnynT(xn) for every x, y ∈ R. Further, few extensions of these results are also presented in the framework of *-ring.

구봉 금-은 광상일대 시추코아(04-1)에서 산출되는 함 티타늄 광물들의 산상과 화학조성 (Occurrence and Chemical Composition of Ti-bearing Minerals from Drilling Core (No.04-1) at Gubong Au-Ag Deposit Area, Republic of Korea)

  • 유봉철
    • 광물과 암석
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    • 제36권3호
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    • pp.185-197
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    • 2023
  • 구봉 금-은 광상은 선캠브리아기의 변성퇴적암류내에 발달된 열극대를 충진한 8개조의 석영맥으로 구성된 조산형과 intrusion-related형이 혼합된 광상으로 과거 한국에서 가장 큰 금-은 광상들 중의 하나였다. 대한광업진흥공사는 이 광상의 남부에서 시추(90-12)를 통한 심도 -728 ML에서 27.9 g/t Au 품위를 갖는 0.9 m 폭을 갖는 석영맥(6호맥)을 착맥하였으며 2004년 재차 6호맥의 재개발 가능성 검토를 위해 시추(04-1)를 수행하였다. 2004년 시추 현장에서 모암, 모암변질 및 석영맥 시료들(04-1)을 채취하여 함 티타늄 광물들(티탄철석, 금홍석)의 산상과 화학조성을 연구하였다. 심도 -275 ML의 광화대에서 관찰되는 금홍석은 모암변질대에서 칼리장석, 흑운모, 석영, 방해석, 녹니석 및 황철석과 함께 산출된다. 심도 -779 ML의 광맥(6호맥)에서 관찰되는 티탄철석과 금홍석은 모암변질대와 석영맥에서 백색운모, 녹니석, 인회석, 저어콘, 석영, 방해석, 자류철석 및 황철석과 함께 산출된다. 이들 광물조합을 토대로, 금홍석은 열수 용액에 의한 모암내 Ti을 풍부하게 함유한 흑운모의 열수변질작용(녹니석화작용) 시 형성된 것으로 생각된다. 티탄철석은 최대 0.09 wt.% (HfO2), 0.39 wt.% (V2O3), 0.54 wt.% (BaO) 함량이 함유되어 있다. 심도 -275 ML과 -779 ML에서 산출되는 금홍석의 화학조성을 비교하면, 심도 -779 ML의 광맥(6호맥)의 금홍석에서 WO3, FeO 및 BaO 원소들의 함량이 높다. 이들 미량원소들은 심도 -275 ML의 금홍석 Ba2+ + Al3+ + Hf4+ + (Nb5+, Ta5+) ↔ 3Ti4+ + Fe2+, 2V4+ + (W5+, Ta5+, Nb5+) ↔ 2Ti4+ + Al3+ + (Fe2+, Ba2+), Al3+ + V4+ + (Nb5+, Ta5+) ↔ 2Ti4+ + 2Fe2+, 심도 -779 ML의 금홍석 2(Fe2+, Ba2+) + Al3+ + (W5+, Nb5+, Ta5+) ↔ 2Ti4+ + (V4+, Hf4+), Fe2+ + Al3+ + Hf4+ + (W5+, Nb5+, Ta5+) ↔ 2Ti4+ + V4+ + Ba2+로써 치환관계가 있었다. 이들 자료와 기 연구된 조산형 금 광상에서 산출되는 함 티타늄 광물들의 화학조성과 비교 검토 본 결과, 구봉 광상의 금홍석들은 다른 조산형 금 광상(운산 광상, Kori Kollo 광상, Big Bell 광상, Meguma 함 금 석영맥)들에서 산출되는 금홍석들보다 상대적으로 산화 환경에서 형성되었음을 알 수 있다.

Study on (n,p) reactions of 58Ni, 99Tc, 99Ru, 131Xe, 133Cs and 186Os radioisotopes used in medicine

  • Hallo M. Abdullah;Ali H. Ahmed
    • Nuclear Engineering and Technology
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    • 제55권1호
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    • pp.304-309
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    • 2023
  • In the last decade, nuclear medicine appears to be a good choice of medicine. 58Co, 99Mo, 99Tc, 99Re, 133Xe and 186Re are very important radionuclides for nuclear medicine. In this study, the excitation functions of 58Ni (n, p) 58Co, 99Tc (n, p) 99Mo, 99Ru (n, p) 99Tc, 131Xe (n, p) 131I, 133Cs (n, p) 133Xe and 186Os (n, p) 186Re nuclear reactions were calculated at neutron energies between 1 and 20 MeV using TALYS 1.95 and EMPIRE 3.2 nuclear codes. Furthermore, the cross sections were calculated with the empirical formula derived in our past study at 14-15 MeV. The obtained results were compared with the measured values in EXFOR library, and with the evaluated data of (JENDL-4.0/HE, JEFF-3.3, TENDL-2019, ENDF/B-VIII.0, IRDFF-II, JENDL/ImPACT-18). The results are in good agreement with those of the evaluated data libraries and experimental results and indicates that these radioisotopes can be produced by smaller cyclotrons.

Dual regulatory effects of PI(4,5)P2 on TREK-2 K+ channel through antagonizing interaction between the alkaline residues (K330 and R355-357) in the cytosolic C-terminal helix

  • Kim, Sung Eun;Kim, Myoung-Hwan;Woo, Joohan;Kim, Sung Joon
    • The Korean Journal of Physiology and Pharmacology
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    • 제24권6호
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    • pp.555-561
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    • 2020
  • TWIK-related two-pore domain K+ channel-2 (TREK-2) has voltage-independent activity and shows additional activation by acidic intracellular pH (pHi) via neutralizing the E332 in the cytoplasmic C terminal (Ct). We reported opposite regulations of TREK-2 by phosphatidylinositol 4,5-bisphosphate (PIP2) via the alkaline K330 and triple Arg residues (R355-357); inhibition and activation, respectively. The G334 between them appeared critical because its mutation (G334A) endowed hTREK-2 with tonic activity, similar to the mutation of the inhibitory K330 (K330A). To further elucidate the role of putative bent conformation at G334, we compared the dual mutation forms, K330A/G334A and G334A/R355-7A, showing higher and lower basal activity, respectively. The results suggested that the tonic activity of G334A owes to a dominant influence from R355-7. Since there are additional triple Arg residues (R377-9) distal to R355-7, we also examined the triple mutant (G334A/R355-7A/R377-9A) that showed tonic inhibition same with G334A/R355-7A. Despite the state of tonic inhibition, the activation by acidic pHi was preserved in both G334A/R355-7A and G334A/R355-7A/R377-9A, similar to the R355-7A. Also, the inhibitory effect of ATP could be commonly demonstrated under the activation by acidic pHi in R355-7A, G334A/R355-7A, and G334A/R355-7A/R377-9A. These results suggest that the putative bent conformation at G334 is important to set the tug-of-war between K330 and R355-7 in the PIP2-dependent regulation of TREK-2.

삼광 금-은 광상에서 산출되는 함 티타늄 광물들의 산상 및 화학조성 (Occurrence and Chemical Composition of Ti-bearing Minerals from Samgwang Au-ag Deposit, Republic of Korea)

  • 유봉철
    • 광물과 암석
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    • 제33권3호
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    • pp.195-214
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    • 2020
  • 삼광 금-은 광상은 과거 한국에서 가장 큰 금-은 광상들 중의 하나였다. 이 광상은 선캠브리아기의 변성퇴적암류내에 발달된 열극대를 충진한 8개조의 석영맥으로 구성된 조산형 금-은 광상이다. 이 광상에서 함 티타늄 광물로는 설석, 티탄철석 및 금홍석이며 설석과 티탄철석은 모암에서만 산출되나 금홍석은 모암과 엽리상 석영맥에서 산출된다. 이들 광물들은 모암에선 흑운모, 백운모, 녹니석, 백색운모, 모나자이트, 저어콘 및 인회석과 엽리상 석영맥에선 백색운모, 녹니석 및 유비철석 등과 함께 산출된다. 설석은 최대 3.94 wt.% (Al2O3), 0.49 wt.% (FeO), 0.52 wt.% (Nb2O5), 0.46 wt.% (Y2O3) 및 0.43 wt.% (V2O5) 값을 갖는다. 이 설석은 0.06~0.14 (Fe/Al 비) 값으로 변성기원의 설석이고 XAl (=Al/Al+Fe3++Ti) 값이 0.06~0.15 값으로 저 함량 알루미늄 설석에 해당된다. 티탄철석은 최대 0.07 wt.% (ZrO2), 0.12 wt.% (HfO2), 0.26 wt.% (Nb2O5), 0.04 wt.% (Sb2O5), 0.13 wt.% (Ta2O5), 2.62 wt.% (As2O5), 0.29 wt.% (V2O5), 0.12 wt.% (Al2O3), 1.59 wt.% (ZnO)로써 As2O5 함량이 높게 산출된다. 금홍석의 화학조성은 모암과 엽리상 석영맥에서 각각 최대 0.35 wt.%, 0.65 wt.% (HfO2), 2.52 wt.%, 0.19 wt.% (WO3), 1.28 wt.%, 1.71 wt.% (Nb2O3), 0.03 wt.%, 0.07 wt.% (Sb2O3), 0.28 wt.%, 0.21 wt.% (As2O5), 0.68 wt.%, 0.70 wt.% (V2O3), 0.48 wt.%, 0.59 wt.% (Cr2O3), 0.70 wt.%, 1.90 wt.% (Al2O3), 4.76 wt.%, 3.17 wt.% (FeO)로써 엽리상 석영맥의 금홍석에서 HfO2, Nb2O3, As2O5, Cr2O3, Al2O3 및 FeO 원소들의 함량이 모암의 금홍석보다 높지만 WO3 원소의 함량은 낮다. 이 미량원소들은 모암의 금홍석[(Fe3+, Al3+, Cr3+) + Hf4++(W5+, As5+, Nb5+) ⟵⟶; 2Ti4++ V4+, 2Fe2++(Al3+, Cr3+) + Hf4++(W5+, As5+, Nb5+) ⟵⟶ 2Ti4++2V4+], 엽리상 석영맥의 금홍석 [(Fe3+, Al3+) + As5+ ⟵⟶ Ti4++ V4+, (Fe3+, Al3+) + As5+ ⟵⟶ Ti4++Hf4+, 4(Fe3+, Al3+) ⟵⟶ Ti4++(W5+, Nb5+) + Cr3+]로써 치환관계가 있었다. 이들 자료를 근거로, 모암내 산출되는 설석, 티탄철석 및 금홍석은 광역변성작용 동안 모암광물들의 변질 시 광물내 존재했던 W5+, Nb5+, As5+, Hf4+, V4+, Cr3+, Al3+, Fe3+, Fe2+ 등과 같은 양이온들의 재 용해 및 농집에 의해 형성되었다. 그후 계속된 연성전단 시 엽리상 석영맥내 금홍석은 열수 용액의 유입에 따른 백색운모와 녹니석의 모암변질작용에 의한 양이온들의 재 용해 및 재 농집과 더불어 초기에 형성된 설석, 티탄철석 및 금홍석과의 반응에 의해 기존에 이들 광물내에 존재하였던 Nb5+, As5+, Hf4+, Cr3+, Al3+, Fe3+, Fe2+과 같은 양이온들의 재농집에 의해 형성된 것으로 생각된다.

Medicinal Plant Lemon Grass (Cymbopogon Citratus) Growth under Salinity and Sodicity

  • Ullah, Muhammad Arshad;Rasheed, Muhammad;Hyder, Syed Ishtiaq
    • 식품보건융합연구
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    • 제6권1호
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    • pp.9-15
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    • 2020
  • Salinity with sodic condition disturbs germination, retards emergence, and slow down seedling development of Lemon Grass (Cymbopogon citratus).Lemongrass is a perennial grass plant widely distributed worldwide and most especially in tropical and subtropical countries. This research experiment was designed to evaluate the influences of (4 dSm-1+ 13.5 (mmol L-1)-1/2, 5 dSm-1+ 25 (mmol L-1)1/2, 5 dSm-1+ 30 (mmol L-1)1/2, 10 dSm-1+ 25 (mmol L-1)1/2 and 10 dSm-1+ 30 (mmol L-1)1/2) on biomass produce of lemon grass against salt tolerance. The uppermost biomass yield (45.53 gpot-1) was produced by 4 dSm-1+ 13.5 (mmol L-1)1/2 treatment. The increase in the intensity of salts reduced the growth of lemon grass. Lower biomass yield (79.33 gpot-1) was gained at 10 dSm-1+ 30 (mmol L-1)1/2. 5 dSm-1+ 25 (mmol L-1)1/2 treatment performed enhanced outcome i.e. the least reduction % over control (5.87). Salinity- sodicity showed serious effect on the growth reduction from 5.87% to33.60%. This reduction gap was affected by the negative effect of salinity and sodicity on Linseed growth. Salinity- sodicity showed severe impact on the growth reduction from 5.87% to33.60%. Based on the findings, lemon Grass (Cymbopogon citratus).was capable to grow up the maximum at 4 dSm-1+ 13.5 (mmol L-1)1/2 treatment.

GEOMETRY OF BILINEAR FORMS ON A NORMED SPACE ℝn

  • Sung Guen Kim
    • 대한수학회지
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    • 제60권1호
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    • pp.213-225
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    • 2023
  • For every n ≥ 2, let ℝn‖·‖ be Rn with a norm ‖·‖ such that its unit ball has finitely many extreme points more than 2n. We devote to the description of the sets of extreme and exposed points of the closed unit balls of 𝓛(2n‖·‖) and 𝓛𝒮(2n‖·‖), where 𝓛(2n‖·‖) is the space of bilinear forms on ℝn‖·‖, and 𝓛𝒮(2n‖·‖) is the subspace of 𝓛(2n‖·‖) consisting of symmetric bilinear forms. Let 𝓕 = 𝓛(2n‖·‖) or 𝓛𝒮(2n‖·‖). First we classify the extreme and exposed points of the closed unit ball of 𝓕. We also show that every extreme point of the closed unit ball of 𝓕 is exposed. It is shown that ext B𝓛𝒮(2n‖·‖) = ext B𝓛(2n‖·‖) ∩ 𝓛𝒮(2n‖·‖) and exp B𝓛𝒮(2n‖·‖) = exp B𝓛(2n‖·‖) ∩ 𝓛𝒮(2n‖·‖), which expand some results of [18, 23, 28, 29, 35, 38, 40, 41, 43].

OBTUSE MATRIX OF ARITHMETIC TABLE

  • Eunmi Choi
    • East Asian mathematical journal
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    • 제40권3호
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    • pp.329-339
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    • 2024
  • In the work we generate arithmetic matrix P(c,b,a) of (cx2 + bx+a)n from a Pascal matrix P(1,1). We extend an identity P(1,1))O(1,1) = P(1,1,1) with an obtuse matrix O(1,1) to k degree polynomials. For the purpose we study P(1,1)kO(1,1) and find generating polynomials of O(1,1)k.