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Effects of Imposing Import Tariffs on a Country's Economic Growth-a Case Study on Malawi

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Effects of Imposing Import Tariffs on a Country's Economic G...

作者： TAPIWA RUTH NG'oma 河北大学

学位级别：硕士

There has been an ongoing debate as to whether there is any relationship betweenimposition of import tariffs and economic growth in developing countries. Thus, this paperaims at empirically and theoretically analysing the effects that imposition of import tariffs haveon economic growth in Malawi over the period of1982–2011. This relationship is examinedusing the Autoregressive Moving Average (ARIMA) model which will test the effect of animplemented import tariff policy on GDP growth.The Autoregressive Moving Average regression results reveal that there is a relationshipbetween imposed import tariffs and economic growth in Malawi, that is, a reduction in theaverage import tariff rate leads to a rise in GDP growth. These results strongly support the role,import trade can play in Malawi’s economic development. This means that by adopting goodimport tariff policies, Malawi will eventually boost domestic production hence the GDPgrowth.

关键词： Import tariffs Economic growth and Malawi Revenue Authority

The Boson peak in confined water： An experimental investigation of the liquid-liquid phase transition hypothesis

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Frontiers of physics 2015年第5期10卷 43-49页

作者： Francesco Mallamace Carmelo Corsaro Domenico Mallamace Zhe Wang sow-Hsin Chen Department of Nuclear Science and Engineering Massachusetts Institute of Technology Cambridge MA 02139 USA Dipartimento di Fisica e Scienze della Terra Universita di Messina I-98166 Messina Italy Consiglio Nazionale delle Ricerche-IPCF Messina I-98166 Messina Italy Dipartimento di Scienze dell'Ambiente della Sicurezza del Territorio degli Alimentie e della Salute Universit5 di Messina Viale F. Stagno d'Alcontres 31 98166 Messina Italy

The Boson peak （BP） of deeply cooled confined water is studied by using inelastic neutron scattering （INS） in a large interval of the （P, T） phase plane. By taking into account the different behavior of such a collective vibrational mode in both strong and fragile glasses as well as in glass-forming materials, we were able to determine the Widom line that characterizes supercooled bulk water within the frame of the liquid-liquid phase transition （LLPT） hypothesis. The peak frequency and width of the BP correlated with the water polymorphism of the LLPT scenario, allowing us to distinguish the ＂low-density liquid＂（LDL） and ＂high-density liquid＂（HDL） phases in deeply cooled bulk water. Moreover, the BP properties afford a further confirmation of the Widom line temperature Tw as the （P, T） locus in which the local structure of water transforms from a predominately LDL form to a predominately HDL form.

关键词： supercooled water liquid-liquid phase transition (LLPT) inelastic neutron scattering

Hydrophilic and hydrophobic competition in water-methanol solutions

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Science China(Physics,Mechanics & Astronomy) 2019年第10期62卷 8-15页

作者： Domenico Mallamace sow-Hsin Chen Carmelo Corsaro Enza Fazio Francesco Mallamace HEugene Stanley Dipartimento MIFT Universita di MessinaMessina 1-98166Italy Department of Nuclear Science and Engineering Massachusetts Institute of TechnologyCambridge MA 02139USA Istituto dei Sistemi Complessi(ISC)-CNR Rome 00185Italy Center for Polymer Studies and Department of Physics Boston UniversityBoston MA 02215USA

We study the thermal behavior of the longitudinal spin-lattice, T1, and the transverse spin-spin, T2, relaxation times of the macroscopic magnetization in water/methanol solutions. Our aim is to investigate the reciprocal influence of hydrophobic effects on water properties and of hydrophilicity（via hydrogen bond, HB, interactions） on the solute. Using classical Nuclear Magnetic Resonance spectroscopy, we find a single characteristic correlation time τcthat reflects all local structural configurations and characterizes the thermal motion effects of the magnetic nuclei on the spin-spin interaction. We find that in the supercooled regime the correlations are stronger, with respect to ambient temperature, because the HB interactions have a lifetime long enough to sustain a stable water network. However, increasing the temperature, progressively decreases the HB interaction lifetime and destroys the water clusters with a consequent decoupling in the dynamic modes of the system. In addition, at temperatures higher than about 265 K, the hydrophobicity becomes gradually stronger and governs the physical properties of the solutions.

关键词： hydrophobic-hydrophilic interactions water systems thermal properties

Optimization and application of blasting parameters based on the "pushing-wall" mechanism

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International Journal of Minerals,Metallurgy and Materials 2012年第10期19卷 879-885页

作者： Feng-yu Ren Thierno Amadou Mouctar sow Rong-xing He Xin-rui Liu College of Resources and Civil Engineering Northeastern University

The large structure parameter of a sublevel caving method was used in Beiminghe iron mine. The ores were generally lower than the medium hardness and easy to be driUed and blasted. However, the questions of boulder yield, ＂pushing-wall＂ accident rate, and brow damage rate were not effectively controlled in practical blasting. The model test of a similar material shows that the charge concentration of bottom blastholes in the sector is too high; the pushing wall is the fundamental reason for the poor blasting effect. One of the main methods to adjust the explosive distribution is to increase the length of charged blastholes. Therefore, the field tests with respect to increasing the length of uncharged blastholes were made in 12# stope of-95 subsection and 6# stope of Beiminghe iron mine. This paper took the test result of 12# stope as an example to analyze the impact of charge structure on blasting effect and design an appropriate blasting parameter that is to similar to No. 12 stope.

关键词： iron mines and mining excavation blasting optimization

Selective enriching of trionic emission in a WS2-ZnO hybrid through type-Ⅱ band alignment

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Science China(Information Sciences) 2023年第6期66卷 63-70页

作者： Jin Feng LEONG Kim Yong LIM Xiao WU Qinghua XU Chorng Haur sow Eng Tuan POH Department of Physics National University of Singapore Department of Chemistry National University of Singapore

Strategies to modulate the exciton dynamics in ultrathin two-dimensional(2D)semiconductors have always been an integral component in the bid towards improved optoelectronics and quantum photonic devices. The capability to non-destructively tune the relaxation dynamics, valley polarization, binding energies, and population ratio of various excitonic species has been well-sought for advanced *** the rationale design of a WS2-ZnO hybrid platform, we present a distinct increment in the trion-toexciton ratio for WS2emission across a patterned heterostructure. The shift in dominant excitonic species arose due to the efficient charge segregation at the spatially confined interface of the type-Ⅱ *** to the charge transfer process, the resultant emission profile presents up to four times amplification in the trion-to-exciton ratio, with temperature variable trion binding energies up to 59 meV. Since trions possess non-zero charge and spin degrees of freedom, the provision of a higher density of trions with increased binding stability would encourage new opportunities for reproducible optoelectronics and quantum emitters.

关键词： heterostructure trions type-II band alignment

Liver dysfunction and SARS-CoV-2 infection

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World Journal of Gastroenterology 2021年第26期27卷 3951-3970页

作者： Abraham Edgar Gracia-Ramos Joel oma. Jaquez-Quintana Raúl Contreras-oma.a Moises Auron Department of Internal Medicine General HospitalNational Medical Center"La Raza"Instituto Mexicano del Seguro SocialMexico City 02990Mexico Gastroenterology Service and Department of Internal Medicine Faculty of MedicineUniversity Hospital"Dr.JoséE.González"Universidad Autónoma de Nuevo LeónMonterrey 64460Mexico Centro de Estudio e Investigación en Enfermedades Hepáticas y Toxicológicas(CEIHET) Pachuca 42184Mexico Departments of Hospital Medicine and Pediatric Hospital Medicine Cleveland ClinicClevelandOH 44195United States

Severe acute respiratory syndrome coronavirus 2 infection is the cause of coronavirus disease 2019(COVID-19),which predominantly affects the respiratory system;it also causes systemic and multi-organic *** damage is among the main extrapulmonary ***-19-associated liver injury is defined as any liver damage occurring during the disease course and treatment of COVID-19 in patients with or without pre-existing liver disease,and occurs in approximately one in five *** liver test results have been associated with a more severe course of COVID-19 and other complications,including *** linking COVID-19 to liver injury are *** consideration should be made for patients with pre-existing liver disease,such as metabolic dysfunction-associated fatty liver disease,chronic liver disease due to viral or autoimmune disease,liver transplant carriers,or cirrhosis,given the risk for more severe *** manuscript summarizes the current lines of evidence on COVID-19-associated liver injury regarding pathophysiology,clinical significance,and management in both patients with or without preexisting liver disease,to facilitate clinicians’access to updated information and patient ***,we mention the ideas and recommendations to be considered for future research.

关键词： SARS-CoV-2 Coronavirus COVID-19 Liver Liver diseases Liver failure Liver injury Cirrhosis

Bolstering functionality in multilayer and bilayer WS2 via focused laser micro-engraving

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Science China(Information Sciences) 2023年第6期66卷 94-101页

作者： Si Min CHAN Eng Tuan POH Jin Feng LEONG Kuan Eng Johnson GOH Chorng Haur sow Department of Physics National University of Singapore Institute of Materials Research and Engineering Agency for ScienceTechnology and Research (A~*STAR) Division of Physics and Applied Physics School of Physical and Mathematical SciencesNanyang Technological University

Laser thinning of multilayer transition metal dichalcogenide(TMD)crystals has long been explored for its potential to produce localized doma.ns of optically functional monolayers. Despite the high spatial control and resolution of the laser, the range of appropriate applications for these laser-thinned doma.ns is still limited by the peripheral regions of unaltered thick multilayers. Herein, we report a newfound property of the laser-thinned regions to adhere strongly to the underlying substrate when lasered down to the monolayer limit. Upon a brief sonication in various solvents, the surrounding pristine multilayers can be lifted off, solely leaving behind the post-lasered monolayer patterns. Coupled with the flexible maneuver of the laser, various monolayer designs can be achieved, including micro-antenna, waveguide, and electrode geometries with lateral line widths at 1.5 μm resolution. Furthermore, we also detail the optical properties of the monolayers obtained from laser thinning, with those acquired from multilayers containing more defectbound excitons, whereas those lasered from bilayers presenting a trion-dominated profile similar to as-grown monolayers. Together, these findings allow for faster and more efficient multilayer removal and areal shaping of optically active monolayer doma.ns, in comparison to multistep and complex standard lithographic etching(lithography–etch–develop)procedures.

关键词： WS$_2$ monolayer micro-patterning focused laser sonication lift-off

An Empirical Study on the Impact of Corporate Governance Practices on the Performance of Commercial Banks: Evidence from Senegal

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An Empirical Study on the Impact of Corporate Governance Pra...

作者： CHEIKH AHMADOU TIDJANE sow 江苏大学

学位级别：硕士

公司治理对于影响全世界银行,尤其是塞内加尔银行的绩效至关重要。公司治理仍然是决定银行绩效的重要变量。关于公司治理对银行绩效的重要性,该研究试图探索公司治理实践对塞内加尔银行业的影响。为了评估关于银行绩效的公司治理实践,... 详细信息

公司治理对于影响全世界银行,尤其是塞内加尔银行的绩效至关重要。公司治理仍然是决定银行绩效的重要变量。关于公司治理对银行绩效的重要性,该研究试图探索公司治理实践对塞内加尔银行业的影响。为了评估关于银行绩效的公司治理实践,该研究采用了定量研究设计。定量研究的应用使研究可以方便地访问和使用从辅助数据获得的统计分析来确认事实和数据。塞内加尔的25家银行商业银行共吸引了8家银行。选择这些银行的依据是,这些银行已审计了已发布的财务报表。在分析数据时,该研究通过固定效应回归模型采用了SPPSS和Stata软件。该研究结果表明,董事会规模具有较小的正值,但从统计学上讲与银行的盈利能力无关。结果表明,董事会规模对在塞内加尔经营的全能银行的盈利能力影响不大。这意味着较大的电路板尺寸将有助于增加存储量,但是步伐或速度非常慢。此外,研究结果还表明,董事会的独立性,董事会的多样性以及董事会委员会的统计意义重大,并且与绩效呈正相关。该研究具有重要意义,因为它不仅有助于减少银行倒闭,而且还可以帮助公司吸引大量的本地资本或外国直接投资（FDI）。这可以促进塞内加尔更快的经济增长和发展。在这方面,塞内加尔中央银行,证券交易委员会和私营企业基金会以及其他利益相关者为改善塞内加尔公司的治理标准所作的努力可以被视为朝着正确方向迈出的一步。该研究的一项重要政策建议是,全能银行必须拥有由多数非执行董事组成的董事会。此外,研究建议塞内加尔银行建设所有银行董事的能力,以改善银行一级的公司治理,从而有助于避免系统中潜在的财务漏洞,并有助于加强银行业市场和行业发展。

关键词：公司治理财务绩效银行塞内加尔

Composition-dependent ultra-high photoconductivity in ternary CdSxSe1-x nanobelts as measured by optical pump-terahertz probe spectroscopy

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Nano Research 2013年第11期6卷 808-821页

作者： Hongwei Liu Junpeng Lu Minrui Zheng Sing Hai Tang Xinhai Zhang Chorng Haur sow Department of Physics 2 Science Drive 3 National University of Singapore 117542 Singapore Institute of Materials Research and Engineering Agency for Science Technology and Research (A'STAR) 3 Research Link 117502 Singapore

We employ optical pump-terahertz probe spectroscopy to investigate the composition-dependent photoconductivity in ternary CdSxSel_x nanobelts. The observed carrier dynamics of CdS nanobelts display much shorter lifetime than those of ternary CdSKSel_K nanobelts. This indicates the implementation of CdS nanobelts as ultrafast switching devices with a switching speed potentially up to 46.7 GHz. Surprisingly, ternary CdS,-Sel_x nanobelts are found to exhibit much higher photoconductivity than binary CdS and CdSe. This is attributed to the higher photocarrier densities in ternary compounds. In addition, the presence of Se in samples resulted in prominent CdSe-like transverse optical （TO） phonon modes due to electron-phonon interactions. The strength of this mode shows a large drop upon photoexcitation but recovers gradually with time. These results demonstrated that growth of ternary nanostructures can be utilized to alleviate the high surface defect density in nanostructures and improve their photoconductivity.

关键词： nanoma.erials andnanostructures optical materials photoconductivity ternary alloys THz spectroscopy