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Chinese Physics B 2017年第10期26卷 339-347页

作者： F Parvin s h naqib Department of Physics University of Rajshahi

The elastic, thermodynamic, electronic, and optical properties of recently discovered and potentially technologically important transition metal boride NbRuB, are investigated using the density functional formalism. Both generalized gradient approximation （GGA） and local density approximation （LDA） are used for optimizing the geometry and for estimating various elastic moduli and constants. The optical properties of NbRuB are studied for the first time with different photon polarizations. The frequency （energy） dependence of various optical constants complement quite well the essential features of the electronic band structure calculations. Debye temperature of NbRuB is estimated from the thermodynamical study. All these theoretical estimates are compared with published results, where available, and discussed in detail. Both electronic band structure and optical conductivity reveal robust metallic characteristics. The NbRuB possesses significant elastic anisotropy. Electronic features, on the other hand, are almost isotropic in nature. The effects of electronic band structure and Debye temperature on the emergence of superconductivity are also analyzed.

关键词： hard materials ternary borides DFT calculations electronic band structure optical properties superconductivity

Field-dependent resistive transitions in YBa_2Cu_3O_(7-δ) thin films:Influence of the pseudogap on vortex dynamics

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Chinese Physics B 2015年第1期24卷 467-473页

作者： s h naqib R s Islam Department of Physics University of RajshahiRajshahi-6205 Bangladesh

The nature of resistive transition of high-quality crystalline thin films of YBa2Cu3O7-δhas been studied under magnetic fields（h） applied along the c direction over a wide range of doped holes, p, in the Cu O2 planes. The field- and temperature-dependent in-plane resistivity, ρab（T, h）, has been analyzed within the thermally assisted flux-flow（TAFF）formalism. The flux activation energy, U（T, h）, has been extracted from this analysis. The low-T part of the ρab（T, h）data can be described by an activation energy having the functional form of U（T, h） =（1- t）m（h-0/h）β, where t = T /Tc（reduced temperature）, and h0 is a field scale that primarily determines the magnitude of U（T, h）. The temperature exponent, m, shows a systematic variation with p, whereas the field exponent, β, is insensitive to the p values and is close to unity. The h0, on the other hand, changes rapidly as p is varied. U（T, h） is linked to the pinning potential and consequently on the superconducting condensation energy. since the normal state pseudogap directly affects superconducting condensation energy, a clear correspondence between h0 and the PG energy scale, ε g, is found. Possible implications of these results are discussed.

关键词： Y123 superconductors thermally assisted flux-flow model activation energy pseudogap

New ternary superconducting compound LaRu2As2： Physical properties from density functional theory calculations

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Chinese Physics B 2017年第3期26卷 453-460页

作者： M A hadi M s Ali s h naqib A K M A Islam Department of Physics University of Rajshahi Rajshahi 6205 Bangladesh Department of Physics Pabna University of Science and Technology Pabna 6600 Bangladesh International Islamic University Chittagong Chittagong 4203 Bangladesh

In this paper, we perform the density functional theory （DFT） -based calculations by the first-principles pseudopo- tential method to investigate the physical properties of the newly discovered superconductor LaRu2As2 for the first time. The optimized structural parameters are in good agreement with the experimental results. The calculated independent elas- tic constants ensure the mechanical stability of the compound. The calculated Cauchy pressure, Pugh＇s ratio as well as Poisson＇s ratio indicate that LaRu2As2 should behave as a ductile material. Due to low Debye temperature, LaRu2As2 may be used as a thermal barrier coating （TBC） material. The new compound should exhibit metallic nature as its valence bands overlap considerably with the conduction bands. LaRu2As2 is expected to be a soft material and easily machinable because of its low hardness value of 6.8 GPa. The multi-band nature is observed in the calculated Fermi surface. A highly anisotropic combination of ionic, covalent and metallic interactions is expected to be in accordance with charge density calculation.

关键词： new superconductor LaRu2As2 density functional theory (DFT) calculations mechanical proper-ties electronic features

An ab initio investigation of vibrational, thermodynamic, and optical properties of sc_2AlC MAX compound

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Chinese Physics B 2016年第10期25卷 103-108页

作者： M A Ali M T Nasir M R Khatun A K M A Islam s h naqib Department of Physics Chittagong University of Engineering and Technology Department of Arts & sciences Bangladesh Army University of Science and Technology Department of Physics University of Rajshahi International Islamic University Chittagong

The structural vibrational, thermodynamical, and optical properties of potentially technologically important, weakly coupled MAX compound, sc2 Al C are calculated using density functional theory(DFT). The structural properties of scAlC are compared with the results reported earlier. The vibrational, thermodynamical, and optical properties are theoretically estimated for the first time. The phonon dispersion curve is calculated and the dynamical stability of this compound is investigated. The optical and acoustic modes are observed clearly. We calculate the helmholtz free energy(F), internal energy(E), entropy(s), and specific heat capacity(Cv) from the phonon density of states. Various optical parameters are also calculated. The reflectance spectrum shows that this compound has the potential to be used as an efficient solar reflector.

关键词： MAX compound phonon dispersion thermodynamical properties optical properties

structural, elastic, and electronic properties of recently discovered ternary silicide superconductor Li_2Irsi_3: An ab-initio study

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Chinese Physics B 2015年第11期24卷 478-482页

作者： M.A.hadi M.A.Alam M.Roknuzzaman M.T.Nasir A.K.M.A.Islam s.h.naqib Department of Physics University of Rajshahi Department of Physics Rajshahi University of Engineering and Technology Department of Physics Jessore University of Science and Technology International Islamic University Chittagong

The structural, elastic, and electronic properties of the very recently discovered ternary silicide superconductor, Li2Irsi3, are calculated using an ab-initio technique. We adopt the plane-wave pseudopotential approach within the frame- work of the first-principles density functional theory （DFT） implemented by the CAsTEP code. The calculated structural parameters show reasonable agreement with the experimental results. The elastic moduli of this interesting material are calculated for the first time. The electronic band structure and electronic energy density of states indicate the strong cova- lent Ir-si and si-si bonding, which leads to the formation of the rigid structure of Li2Irsi3. strong covalency gives rise to a high Debye temperature in this system. We discuss the theoretical results in detail in this paper.

关键词： silicide superconductor crystal structure elastic properties electronic structures

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X公司的招聘和选拔流程优化研究

X公司的招聘和选拔流程优化研究

作者： naqib Yussof 上海外国语大学

学位级别：硕士

组织的成功取决于其员工的有效性。没有高素质的劳动力,一个组织注定要有平庸的表现。组织的招聘和选拔实践是人力资源管理最重要的职能之一。招聘和选拔劳动力市场中最优秀的人才涉及各种人力资源管理活动。招聘和选拔作为一种人力资... 详细信息

组织的成功取决于其员工的有效性。没有高素质的劳动力,一个组织注定要有平庸的表现。组织的招聘和选拔实践是人力资源管理最重要的职能之一。招聘和选拔劳动力市场中最优秀的人才涉及各种人力资源管理活动。招聘和选拔作为一种人力资源管理职能,是在实现其最终目标方面最关键地影响组织绩效的活动之一(Costello,2006)。根据Beer等人(1984)的说法,招募和选拔不仅试图吸引,获得和保留组织实现战略目标所需的人力资源的数量和质量,而且还可能对其组成产生重大影响。劳动力,员工与组织的需求和文化以及长期就业稳定性的最终契合。有效利用招聘和甄选政策和做法也可以改善员工的承诺和绩效,并减少他们的缺勤率和离职率。该研究的主要目的是确定X公司现有的招聘和选拔实践。该公司总部设在上海,本研究的重点是招聘和选择两个非常重要的职位X公司,即业务发展经理和财务顾问。由于公司业务的性质,这两个职位主要由外国人才占据。通过识别公司遇到的挑战,并提供优化策略和建议,以改善他们的招聘和选拔过程。本研究报告还回顾了有关招募和选拔的文献。X公司使用外部和内部招聘来源。它将讨论五个理论框架:人力资本理论,资源依赖理论,五大人格理论,印象管理理论和荷兰职业倾向理论。它使用PEsT分析来评估影响公司招聘和选择过程的外部因素。调查问题用于确定受访者对X公司员工招聘和选拔实践的当前问题的看法。然后分析从调查中获得的数据。研究结果显示,有五种主要的招募和选择方法。按照高度认可的方法排名前三位最常用的员工选择媒介包括在线广告,员工推荐和校园招聘。还得出大多数员工只在X公司工作不到一年-这表明公司的员工流动率很高。确定了五个关键问题和问题,即时间限制,招聘和选拔过程的复杂性,招聘过程的低效率,找到想要搬迁和吸引合适候选人的人。还有人透露,法律,政治和社会文化因素等环境因素通常会影响选拔过程。虽然组织必须制定适合其个人需求的招聘和甄选计划,但他们必须采用有效的评估方法,以确保他们所实施的程序尽可能高效和有效。满足这些需求。在文献综述中强调了评估的重要性,因为组织必须了解他们是否真正从他们现有的程序中获益。但是,通过返回的调查和进行的访谈确定,目前该组织没有适当的程序来评估招聘教师时招聘和选拔方法的有效性。强烈建议在不久的将来,组织引入诸如文献综述中提出的措施,以评估其招聘和选拔过程的有效性。这不仅有助于组织满足其人员需求,而且还将促进区域运营管理人员建立正确和错误的方法

关键词： X公司人力资源招聘与选拔 PEsT分析优化策略

heterosis and Inbreeding Depression in F<sub>2</sub>Populations of Upland Cotton (<i>Gossypium hirsutum</i>L.)

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Agricultural sciences 2017年第11期8卷 1283-1295页

作者： Bilal Ahmed Khan naqib Ullah Khan Mehboob Ahmed Mazhar Iqbal Ihsan Ullah Maria saleem Isma Khurshid Aneela Kanwal hazara Agriculture Research station Abbottabad Pakistan University of Agriculture Peshawar Peshawar Pakistan

hybrid cotton production through exploitation of heterosis is the only way for having vertical improvement and betterment in seed cotton yield which has been stagnated in the recent years. The current study was conducted to evaluate the performance of F2 population for studying mean performance, heterotic effects and inbreeding depression in upland cotton for polygenic traits. Parental genotypes and their F2s were sown at Khyber Pakhtunkhwa Agricultural University, Peshawar during 2010, manually. All the traits revealed highly significant (p ≤ 0.01) variations for both parents and their F2 hybrids. Mean performance for parents and their F2 hybrids is: (5.26 to 7.12 & 4.43 to 6.60) seeds locule-1, (21.10 to 28.03 & 20.40 to 28.50) seed boll-1, (32.20 to 34.80 & 32.22 to 35.05) lint% and (62.87 to 85.47 & 45.94 to 92.04) seed cotton yield plant-1, respectively. heterotic effects found over mid parent and better parent were: 66.66% & 46.66% (seeds locule-1), 60% & 30% (seed boll-1), 43.33% & 30% (lint %) and 36.66% & 16.66% (seed cotton yield plant-1), respectively. For the parameters: seeds locule-1 (11 & 10), seeds boll-1 (2 & 1) and seed cotton yield plant-1 (3 & 1) showed positive highly significant heterosis for both mid and better parent, respectively while lint% did not reveal any positive significant heterosis. F2 populations i.e. CIM-499 × CIM-554 and CIM-554 × CIM-499 revealed highly significant heterotic effects over mid and better parent for all the traits except lint % while CIM-554 × CIM-707 showed highly significant heterotic effects for seeds locule-1 and seed cotton yield palnt-1. Positive economic heterotic effects were also exhibited by more than 50% of the F2 population i.e., 76.66% for seed locule-1, 50% for seeds boll-1, 3.33% for lint% and 20% for seed cotton yield plant-1, respectively. By comparing F2 mean values with F1s, only lint % showed (0.00% to 15.55%) maximum inbreeding depression while negligible amount of inbreeding depression was obs

关键词： heterosis Inbreeding Depression Lint F2

Neuroblastoma in saudi Children: A single Center Experience (2006-2014)

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Journal of Cancer Therapy 2015年第10期6卷 896-905页

作者： Zaid Al naqib Atif A. Ahmed Musa Al harbi Fahad Al Manjomi Zaheer Ullah Khan Awatif Alanazi Othman Mosleh Walid Ballourah Mohammed Rayis Pediatric hematology/Oncology Division King Fahad Medical City Riyadh Saudi Arabia Department of Pathology and Laboratory Medicine Children’s Mercy Hospital Kansas City USA

Introduction: Neuroblastoma is the most common extracranial solid tumor in childhood and survival rate has improved during the last few decades. Only a few studies, related to Neuroblastoma in saudi Arabian children, have been performed. We report epidemiologic data and our clinical experience from the department of Pediatric hematology Oncology (PhO), King Fahad Medical City (KFMC), Riyadh, saudi Arabia. Method: A retrospective observational study of all patients, with diagnosis of Neuroblastoma, who attended PhO-KFMC from July 2006 to June 2014 was performed. The survival periods (overall survival and disease-free survival) and the final outcomes for patients treated and followed at KFMC were recorded. The survival data were statistically correlated with the clinical, pathological and biological features of patients and tumors and compared to national and international cohorts. Results: Eight-year data were available for the 42 patients of which 22 (52.4%) were male and 20 (47.6%) were females. Age at diagnosis ranged 0 - 91 months with a mean and median of 26.3 and 18.5 months respectively. 16 (38.1%) patients were under one year and 26 (61.9%) above 1 year of age. The event-free survival (EFs) and overall survival (Os) rates were 66.5% and 71.5% respectively. EFs and Os among those who were sentation was 75% and 82%, whereas ≥1 yr age group had 59% and 62% survival rates respectively. Patients with tumors in the adrenal had considerably lower EFs (59%) and Os (63%);in comparison to patients with tumors sites other than the adrenal who had EFs and Os of 85% and 89% respectively. Both EFs and Os survival rates at the end of follow-up interval were 100.0%, in the low and intermediate risk groups. In contrast, patients in the high risk group had EFs and Os rates of 44% and 48% respectively. This difference was statistically significant (p sion: Our results are very encouraging and comparable with known published international cohorts

关键词： Children Neuroblastoma saudi Arabia survival