检索结果-南通市图书馆

Antimonene-based saturable absorber for a soliton mode-locked and Q-switched fiber laser in the 2 μm wavelength region

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2023年第6期32卷 259-269页

作者： H Ahmad B Nizamani m Z Samion N Yusoff m F Ismail Photonics Research Centre Universiti Malaya50603 Kuala LumpurMalaysia Physics Department Faculty of ScienceUniversiti Malaya50603 Kuala LumpurMalaysia Distinguished Visiting Professor Universiti Kuala Lumpur British Malaysian Institute(UniKL BMI)Batu 8Jln Sungai Pusu53100SelangorMalaysia

We demonstrate antimonene as a saturable absorber(SA) to generate an ultrafast mode-locked and Q-switched laser in the 2 μm wavelength region. The two antimonene-based SAs were prepared and inserted separately in a thulium–holmiumdoped fiber laser to produce the pulsed laser. Antimonene was coated onto a tapered fiber to generate soliton mode-locked pulses and used in thin-film form for the generation of Q-switched pulses. The mode-locking was stable within a pump power of 267 m W–511 m W, and the laser operated at a central wavelength of 1897.4 nm. The mode-locked laser had a pulse width of 1.3 ps and a repetition rate of 12.6 mHz, with a signal-to-noise ratio of 64 d B. Q-switched laser operation was stable at a wavelength of 1890.1 nm within a pump power of 312 m W–381 m W. With the increase in pump power from 312 m W to 381 m W, the repetition rate increased to a maximum of 56.63 k Hz and the pulse width decreased to a minimum value of 2.85 μs. Wide-range tunability of the Q-switched laser was also realized within the wavelength range of1882 nm–1936 nm.

关键词： mode-locking Q-switched fiber laser optical saturable absorber

One-loop approximation of mφller scattering in generalized Krein-space quantization

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,mechanics & Astronomy) 2009年第2期52卷 212-217页

作者： F. PAYANDEH m. mEHRAFARIN m. V. TAKOOK Physics Department Amirkabir University of Technology Payame Noor University Physics Department Razi University

It has been shown that the negative-norm states necessarily appear in a covariant quantization of the free minimally coupled scalar field in de Sitter spacetime. In this processes ultraviolet and infrared di- vergences have been automatically eliminated. A natural renormalization of the one-loop interacting quantum field in minkowski spacetime (λφ 4) has been achieved through the consideration of the nega- tive-norm states defined in Krein space. It has been shown that the combination of quantum field theory in Krein space together with consideration of quantum metric fluctuation, results in quantum field the- ory without any divergences. Pursuing this approach, we express Wick’s theorem and calculate mφller scattering in the one-loop approximation in generalized Krein space. The mathematical consequence of this method is the disappearance of the ultraviolet divergence in the one-loop approximation.

关键词： quantum field theory Krein space negative energy states

2D CFD Analysis and Experimental Analysis on the Effect of Hub to Tip Ratios on the Performance of 0.6 m Impulse Turbine

在线全文

学校读者我要写书评

暂无评论

Journal of Thermal Science 2004年第4期13卷 315-320页

作者： A. THAKKER m.El. HEmRY Wave Energy Research Team Department of mechanical and Aeronautical Engineering University of Limerick IrelandWave Energy Research Team Department of Mechanical and Aeronautical Engineering University of Limerick Ireland

The objective of this paper is to present the performance comparison of 2D Computational Fluid Dynamics (CFD) analysis with experimental analysis of 0.6 m impulse turbine with fixed guide vanes for both 0.6 and 0.7 hub to tip ratio (H/T). Also the comparison of 2D CFD analysis of the said turbine with different values of H/T ranging from 0.5 to 0.7. A 2D-cascade model was used for CFD analysis while uni-directional steady flow was used for experimental analysis. The blade and guide vane geometries are based on 0.6 m rotor diameter, with optimum profile, and different H/T of 0.5, 0.6 and 0.7. It was concluded from 2D CFD analysis that 0.5 H/T ratio performances was higher than that of 0.6 and 0.7 H/T at peak efficiency and the operational flow range for 0.5 H/T was found to be wider than that of 0.6 and 0.7 H/T ratio.

关键词： wave energy impulse turbine computational fluid dynamics (CFD).

Fecal tumor m2 pyruvate kinase is not a specific biomarker for colorectal cancer screening

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2007年第19期13卷 2768-2769页

作者： Yogesh m Shastri Jürgen m Stein Department of medicine I-ZAFES Division of Gastroenterology and Clinical Nutrition Johann Wolfgang Goethe-University Hospital Frankfurt am Main Germany

TO THE EDITORWe read with great interest and a bit of surprise the article by Tonus et al. We would share herein our comments about it. The specificity of the fecal tumor m2 pyruvate kinase 0VI2-PK） reported by Tonus et al for diagnosing colorectal cancer （CRC） is 93%. This is considerably higher than in any of the previously published studies. In our work, the maximum specificity of fecal m2- PK is 78% （Table 1）. There is a vast difference of 15% between the previous studies and the current study of Tonus et al, which is difficult to explain. We are skeptical about such a high specificity reported by the authors.

关键词： Gastroenterology

T cell immune responses to SARS-CoV-2 and variants of concern(Alpha and Delta)in infected and vaccinated individuals

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Cellular & molecular Immunology 2021年第11期18卷 2554-2556页

作者： Stanley C.Jordan Bong-Ha Shin Terry-Ann m.Gadsden maggie Chu Anna Petrosyan Catherine N.Le Rachel Zabner Jillian Oft Isabel Pedraza Susan Cheng Ashley Vo Noriko Ammerman Jasmine Plummer Shili Ge max Froch Anders Berg mieko toyoda Ruan Zhang Comprehensive Transplant Center Transplant Immunology LaboratoryCedars-Sinai Medical CenterLos AngelesCAUSA Division of Infectious Diseases Cedars-Sinai Medical CenterLos AngelesCAUSA Department of Cardiology Cedars-Sinai Medical CenterLos AngelesCAUSA Department of Bioinformatics&Functional Genomics Cedars-Sinai Medical CenterLos AngelesCAUSA Department of Pathology&Laboratory medicine Cedars-Sinai Medical CenterLos AngelesCAUSA

Our understanding of immune responses to SARS-CoV-2 and variants of concern(VOCs)has been primarily acquired through analysis of Spike-specific IgG ***,a more comprehensive understanding of the breadth and longevity of immune responses after infection and vaccination requires analysis of cellular ***,we report on T cell immunity in infected and vaccinated individuals,identifying CD4+/CD8+T cell cytokine responses to SARS-CoV-2 and variant peptides(Alpha,B.1.1.7 and Delta,B.1.617.2).

关键词： Alpha infected immunity

measurement of the pion form factor for m_(ππ)～2 between 0.1 and 0.85 GeV^2 with the KLOE detector

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics C 2010年第6期34卷 686-691页

作者： Stefan E.müller Institut für Kernphysik Johannes Gutenberg-Universitt

The KLOE experiment at the φ-factory DAФPNE has measured the pion form factor in the range between 0.1 〈 mππ^2 〈 0.85 GeV^2 using events taken at √s = 1 GeV with a photon emitted at large polar angles in the initial state. This measurement extends the mππ^2 region covered by KLOE ISR measurements of the pion form factor down to the two pion production threshold. The value obtained in this measurement of the dipion contribution to the muon anomalous magnetic moment of △αμ^ππ= （478.5±2-0stat±4.8syst±2.9theo）·10^-10 further confirms the discrepancy between the Standard model evaluation for αμ and the experimental value measured by the （g-2） collaboration at BNL.

关键词： hadronic cross section initial state radiation pion form factor muon anomaly

m2BPGi for assessing liver fibrosis in patients with hepatitis C treated with direct-acting antivirals

在线全文

学校读者我要写书评

暂无评论

World Journal of Gastroenterology 2020年第21期26卷 2864-2876页

作者： Shereen A Saleh mohamed m Salama marwan m Alhusseini Ghada A mohamed Gastroenterology and Hepatology Unit Department of Internal MedicineFaculty of MedicineAin Shams UniversityCairo 11341Egypt

BACKGROUND Assessing liver fibrosis is important for predicting the efficacy of direct-acting antivirals(DAAs)and patient ***-invasive techniques to assess liver fibrosis are becoming ***,serum mac-2 binding protein glycosylation isomer(m2BPGi)was identified as a non-invasive marker of liver *** To investigate the diagnostic accuracy of m2BPGi in assessing liver fibrosis in patients with chronic hepatitis C(CHC)treated with *** From December 2017 to August 2018,80 treatment-naive adult patients with CHC who were eligible for DAAs therapy were consecutively enrolled in this observational cohort *** 12 weeks,65 patients were treated with sofosbuvir/daclatasvir,and 15 patients were treated with sofosbuvir/daclatasvir and a weight-based dose of ribavirin at knowledge and technology association for hepatitis C management clinic,Cairo,*** measured serum m2BPGi levels,PAPAS index,fibrosis-4(FIB-4)score and liver stiffness measurements(LSm)at baseline and 12 weeks after the end of *** m2BPGi levels were measured using enzyme-linked immunosorbent *** All patients achieved sustained virologic response(SVR12)(100%).Serum m2BPGi levels,LSm,FIB-4 score and PAPAS index decreased significantly at SVR12(Pm m2BPGi levels correlated positively with LSm at baseline and SVR12(Pmpared with the FIB-4 score and PAPAS index,m2BPGi was the best marker to distinguish patients with grade F4 fibrosis(AUC=0.801,Pm grade F0-1 fibrosis(AUC=0.713,P=0.012),patients with grade F3-4 from grade F0-2 fibrosis(AUC=0.730,Pm grade F0-1 fibrosis(AUC=0.763,Pm2BPGi had the greatest AUCs for differentiating patients with grade F4 fibrosis(AUC=0.844,Pm grade F0-2 fibrosis(AUC=0.893,P=0.002),patients with grade F3-4 from grade F0-2 fibrosis(AUC=0.891,P<0.001),and patients with grad

关键词： Hepatitis C virus Liver fibrosis Human mac-2 binding protein Antiviral agents Sustained virologic response Elastography

Cu对1470mPa级薄钢板在HCI溶液中氢吸收和扩散的影响

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

现代冶金（内蒙古） 2014年第3期 34-39页

作者： Shunsuke toyoda 日本

在高强度钢中氢的含量达到临界值时会导致氢脆，阐明了钢中加入Cu对抑制在HCl溶液中氢脆的作用，对TS1470mPa级低碳马氏体钢进行了渗氢试验和动态极化检测，钢的成分为0．19％C，0．2％Si，1．3％mn，0．16％Cu和少量的Cr、Ti、Nb和B，... 详细信息

在高强度钢中氢的含量达到临界值时会导致氢脆，阐明了钢中加入Cu对抑制在HCl溶液中氢脆的作用，对TS1470mPa级低碳马氏体钢进行了渗氢试验和动态极化检测，钢的成分为0．19％C，0．2％Si，1．3％mn，0．16％Cu和少量的Cr、Ti、Nb和B，为便于比较，对铁素体钢和珠光体钢也做了同样检测。渗氢试验结果表明，含0．16％cu的钢在0．1N HCl溶液中稳定状态下的渗氢电流（JH）低于参考钢，再者，加入cu后抑制了马氏体钢的JH，减小了阴极电流（ic）和JH／ic比。本研究得出的结果证实了这个假设，即在HCl溶液中钢表面析出1或2μm厚的金属Cu粒子可抑制阴极反应和氢的渗入，在电位梯度渗氢试验中获得氢的扩散常数（Deff），加入cu对Deff影响很小并且与显微组织无关，根据Cu含量和显微组织估计阱位（nx）占有率大于99％。

关键词：钢马氏体氢脆吸氢氢扩散延迟断裂腐蚀铜

T_(m)-Eigenvalues of Odd-Order Tensors

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Communications on Applied mathematics and Computation 2022年第4期4卷 1258-1279页

作者： m.Pakmanesh Hamidreza Afshin Department of mathematics Vali-e-Asr University of RafsanjanRafsanjanIran

In this paper,we propose a definition for eigenvalues of odd-order tensors based on some ***,we define the Schur form and the Jordan canonical form of such tensors,and discuss commuting families of ***,we prove some e... 详细信息

关键词： T_(m)-product T_(m)-eigenvalue T_(m)-Schur form T_(m)-Jordan canonical form Odd-order tensor F_(m)-upper(lower)triangular tensor