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Measurement of the Optical Coherence of a Femtosecond Pulsed Laser by Shearing Interferometry with a Double-Frequency Grating

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Chinese Physics Letters 1998年第1期15卷 32-34页

作者： MING Hai QIAN Jiang-yuan XIE Jian-ping A.b.Fedotov X.Xiao M.M.T.Loy Department of Physics University of Science and Technology of ChinaHefei 230026 Department of Physics Hong Kong University of Science&TechnologyClear Water BayKowloonHong KongChina

Shearing interferometry of an ion-etched holographic double-frequency grating is used to measure the optical coherence of femtosecond pulsed *** experimental results show that the optical coherence of the femtosecond light beam is not only related to the spectral width and size of the light source but is also related to the pulse duration and mode-locked laser *** results of theoretical analysis and numerical calculation are also *** of this research is also discussed.

关键词： Femto holographic interferometry

Simulation aided hot zone design for faster growth of CZ silicon mono crystals

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Rare Metals 2011年第2期30卷 155-159页

作者： CAO Jianwei GAO Yu CHEN Ying ZHANG Guohu QIU Minxiu The State Key Laboratory of Fluid Power Transmission and Control Zhejiang University Hangzhou 310027 China GRINM Semiconductor Materials Co. Ltd Beijing 100088 China

Computer simulation was used for optimizing a hot zone for Czochralski （CZ） silicon crystal growth. The heater structure and heat shield material were investigated. With this optimized hot zone, the temperature gradient near the crystal/melt interface increased and the CZ crystal could be grown at a faster rate. It is a great contribution for saving power consumption.

关键词： crystal growth silicon computer simulation temperature gradient

Is autoimmune hepatitis a frequent finding among HCV patients with intense interface hepatitis?

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World Journal of Gastroenterology 2010年第29期16卷 3704-3708页

作者： Rosilene G badiani Vitória becker Renata M Perez Carla AL Matos Lara b Lemos Valéria P Lanzoni Luis Eduardo C Andrade Alessandra Dellavance Antonio Eduardo b Silva Maria Lucia G Ferraz Division of Gastroenterology Federal University of Sao Paulo04023-900Sao PauloBrazil Department of Internal Medicine Federal University of Rio de Janeiro21941-913Rio de JaneiroBrazil Department of Pathology Immunology Group Fleury Medicine and Health 不详

AIM:To evaluate the overlap of autoimmune hepatitis in hepatitis C virus(HCV)-infected patients with intense interface ***:Among 1759 patients with hepatitis C submitted to liver biopsy,92(5.2%) presented intense interface *** patients were evaluated regarding the presence of antinuclear antibody(ANA),anti-smooth muscle antibody(SMA) and anti-liver/kidney microsomal antibody(LKM-1),levels of γ-globulin and histological findings related to autoimmune hepatitis(plasma cell infiltrate and presence of rosettes).RESULTS:Among patients with hepatitis C and intense interface hepatitis there was a low prevalence of autoantibodies(ANA=12%,SMA=5%,LKM-1=0%) and the median γ-globulin level was within the normal *** histological findings of autoimmune disease were observed in only two cases(2%).After applying the score for diagnosis of autoimmune hepatitis,only one patient was classified with a definitive diagnosis of autoimmune *** overlap with autoimmune hepatitis was not the explanation for the intense necroinflammatory activity in patients with chronic hepatitis C we sought to identify the variables associated with this *** presence of intense interface hepatitis was associated with more advanced age,both at the time of infection and at the time of the biopsy,and higher prevalence of blood transfusion and alcohol ***:Although possible,overlap with autoimmune hepatitis is a very rare association in HCV-infected patients with intense interface hepatitis,an unusual presentation which seems to be related to other host variables.

关键词： Hepatitis C Liver biopsy Antinuclear antibody Autoimmune hepatitis Interface hepatitis

Evidence of Electronic Phase Separation in the Strongly Correlated Semiconductor Ybb_(12)

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Chinese Physics Letters 2022年第12期39卷 65-70页

作者： A.Azarevich N.bolotina O.Khrykina A.bogach E.Zhukova b.Gorshunov A.Melentev Z.bedran A.Alyabyeva M.belyanchikov V.Voronov N.Yu.Shitsevalova V.b.Filipov N.Sluchanko Prokhorov General Physics Institute of the Russian Academy of Sciences Vavilov Str.38Moscow 119991Russia Shubnikov Institute of Crystallography Federal Scientific Research Centre‘Crystallography and Photonics’of Russian Academy of Sciences59 Leninskiy ProspectMoscow 119333Russia Center for Photonics and 2D Materials Moscow Institute of Physics and Technology(National Research University)141700 DolgoprudnyMoscow RegionRussia Institute for Problems of Materials Science NASUKrzhizhanovsky Str.303142 KyivUkraine

We investigate high-quality single-domain crystals of Ybb_(12)using the precise x-ray diffraction technique in combination with the low-temperature polarized THz–infrared spectroscopy and accurate magnetotransport *** is shown for the first time that this archetypal strongly correlated system with a metal-insulator transition to a mysterious dielectric ground state with a metal Fermi surface[Science 362,65(2018)and ibid 362,32(2018)]is actually a heterogeneous compound in the regime of electronic phase *** in the configuration of the discovered dynamic charge stripes are proposed upon *** a result,a conclusion is drawn in favor of a crossover between different patterns of the filamentary electronic structure penetrating the semiconducting matrix of Ybb_(12).We argue that the discovery of stripes in Ybb_(12)is fundamental,elucidating the nature of exotic dielectric state in Kondo insulators.

关键词： insulator Kondo dielectric

CALCULATION OF THE VACANCY VOLUME OF METALS bY MODIFIED bROOKS' MODEL

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Acta Metallurgica Sinica(English Letters) 2004年第6期17卷 888-893页

作者： W.H.Qi M.P.Wang W.Y.Hu b.W.Zhang SchoolofMaterialsScienceandEngineering JiangsuUniversityZhenjiang212013China／／SchoolofMaterialsScienceandEngineeringCentralSouthUniversityChangsha410083China SchoolofMaterialsScienceandEngineering CentralSouthUniversityChangsha410083China DepartmentofAppliedPhysics HunanUniversityChangsha410082China

To modify the shape difference between the spherical vacancy and the realistic vacancy, a shape factor is introduced into brooks' vacancy model. It is shown that the modified model is more efficient in predicting the vacancy volume of metals than the original one, and the calculated vacancy volumes of 17 metals by the modified model agree with the values reported in literatures. Furthermore, the present results show that the vacancy shape may contribute 2%-9% to the whole vacancy volume.

关键词： vacancy volume shape effect metals

NUMERICAL SIMULATION OF MACRO-SEGREGATION IN STEEL INGOT DURING SOLIDIFICATION

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Acta Metallurgica Sinica(English Letters) 2004年第3期17卷 288-294页

作者： C.W.Ma H.F.Shen T.Y.Huang b.C.Liu Department of Mechanical Engineering Tsinghua University Beijing 100084 ChinaDepartment of Mechanical Engineering Tsinghua University Beijing 100084 ChinaDepartment of Mechanical Engineering Tsinghua University Beijing 100084 ChinaDepartment of Mechanical Engineering Tsinghua University Beijing 100084 China

A mathematical model coupling the momentum, energy and species conservation equa-tions was proposed to calculate the macro--segregation of Fe--C alloy ingot during solid-ification. The corresponding simulation software which concurrently solves the macro-scopic mass, momentum, energy and species conservation equations has been developedby applying the SIMPLE algorithm.The thermo--solutal convection in a NH_4 Cl--H_2O ingot is verified and the result showsgood agreement with that reported. Then macro--segregation in a steel ingot is simu-lated by using the developed program. The steel ingot is in a rectangular mold with ariser. The fluid flow is mainly induced by the temperature field and the solid fraction.The macro--segregation pattern is mainly affected by the thermo--induced convectionin the mushy zone. The negative segregation forms along the walls of the casting.The positive segregation forms at the top center of the casting into the riser. Thespecies concentration reaches the peak in the center of the ingot where solidificationends lastly.

关键词： macro-segregation thermo-solutal convection steel ingot numerical simulation

Is there evidence of selection in the dopamine receptor D4 gene in Australian invasive starling populations？

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Current Zoology 2015年第3期61卷 505-519页

作者： Lee Ann ROLLINS Michael R. WHITEHEAD Andrew R WOOLNOUGH Ron SINCLAIR William b. SHERWIN Evolution & Ecology Research Centre Biological Earth and Environmental Sciences University of New South Wales Sydney New South Wales 2052 Australia Centre for Integrative Ecology Life and Environmental Sciences Deakin University Locked Bag 20000 Geelong Victoria 3220 Australia biosecurity Division Department of Economic Development Jobs Transport and Resources 1 Spring Street Melbourne Vic- toria 3000 Australia Vertebrate Pest Research Section Department of Agriculture and Food 100 Bougainvillea Avenue Western Australia 6058 Australia biosecurity SA GPO Box 1671 Adelaide South Australia 5001 Australia Murdoch University Cetacean Research Unit Murdoch University South Road Murdoch Western Australia 6150 Australia Current address: Evolution Ecology and Genetics Research School of Biology The Australian National University Canberra Australia

Although population genetic theory is largely based on the premise that loci under study are selectively neutral, it has been acknowledged that the study of DNA sequence data under the influence of selection can be useful. In some circumstances, these loci show increased population differentiation and gene diversity. Highly polymorphic loci may be especially useful when studying populations having low levels of diversity overall, such as is often the case with threatened or newly established inva- sive populations. Using common starlings Sturnus vulgaris sampled from invasive Australian populations, we investigated se- quence data of the dopamine receptor D4 gene （DRD4）, a locus suspected to be under selection for novelty-seeking behaviour in a range of taxa including humans and passerine birds. We hypothesised that such behaviour may be advantageous when species encounter novel environments, such as during invasion. In addition to analyses to detect the presence of selection, we also esti- mated population differentiation and gene diversity using DRD4 data and compared these estimates to those from microsatellite and mitochondrial DNA sequence data, using the same individuals. We found little evidence for selection on DRD4 in starlings. However, we did find elevated levels of within-population gene diversity when compared to microsatellites and mitochondrial DNA sequence, as well as a greater degree of population differentiation. We suggest that sequence data from putatively non- neutral loci are a useful addition to studies of invasive populations, where low genetic variability is expected

关键词： DRD4 Starling Selection Novelty-seeking behaviour

Low Area PRESENT Cryptography in FPGA Using TRNG-PRNG Key Generation

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Computers, Materials & Continua 2021年第8期68卷 1447-1465页

作者： T.Kowsalya R.Ganesh babu b.D.Parameshachari Anand Nayyar Raja Majid Mehmood Department of Electronic and Communication Engineering Muthayammal Engineering CollegeRasipuramNamakkalTamilnaduIndia Department of Electronics and Communication Engineering SRM TRP Engineering CollegeTiruchirappalliTamilnaduIndia Department of Telecommunication Engineering GSSS Institute of Engineering and Technology for WomenMysuruIndia Faculty of Information Technology Graduate SchoolDuy Tan UniversityDa Nang550000Viet Nam Department of Information and Communication Technology School of Electrical and Computer EngineeringXiamen University MalaysiaSepang43900Malaysia

Lightweight Cryptography(LWC)is widely used to provide integrity,secrecy and authentication for the sensitive ***,the LWC is vulnerable to various constraints such as high-power consumption,time consumption,and hardware utilization and susceptible to the malicious *** order to overcome this,a lightweight block cipher namely PRESENT architecture is proposed to provide the security against malicious *** True Random Number Generator-Pseudo Random Number Generator(TRNG-PRNG)based key generation is proposed to generate the unpredictable keys,being highly difficult to predict by the ***,the hardware utilization of PRESENT architecture is optimized using the Dual port Read Only Memory(DROM).The proposed PRESENT-TRNGPRNG architecture supports the 64-bit input with 80-bit of key *** performance of the PRESENT-TRNG-PRNG architecture is evaluated by means of number of slice registers,flip flops,number of slices Look Up Table(LUT),number of logical elements,slices,bonded input/output block(IOb),frequency,power and *** input retrieval performances analyzed in this PRESENT-TRNG-PRNG architecture are Peak Signal to Noise Ratio(PSNR),Structural Similarity Index(SSIM)and Mean-Square Error(MSE).The PRESENT-TRNG-PRNG architecture is compared with three different existing PRESENT architectures such as PRESENT On-TheFly(PERSENT-OTF),PRESENT Self-Test Structure(PRESENT-STS)and PRESENT-Round Keys(PRESENT-RK).The operating frequency of the PRESENT-TRNG-PRNG is 612.208 MHz for Virtex 5,which is high as compared to the PRESENT-RK.

关键词： Dual port read only memory hardware utilization lightweight cryptography malicious attackers present block cipher pseudo random number generator true random number generator

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马血清致敏后乙醇灌胃对鸡股骨头的影响

郑州大学学报(医学版) 2009年第2期44卷 282-285页

作者：王义生窦浚峰铁伟宾郑州大学第一附属医院骨科河南省高等临床医学重点学科开放实验室

目的:观察马血清致敏后乙醇灌胃对鸡股骨头的影响。方法:取64只9月龄健康雄性三黄鸡随机分为4组,每组16只。A组:马血清+乙醇组;b组:单纯乙醇组;C组:单纯马血清组;D组:空白对照组。于灌胃第4、8周末分批处死,取肝脏及股骨头制作病理切片... 详细信息

目的:观察马血清致敏后乙醇灌胃对鸡股骨头的影响。方法:取64只9月龄健康雄性三黄鸡随机分为4组,每组16只。A组:马血清+乙醇组;b组:单纯乙醇组;C组:单纯马血清组;D组:空白对照组。于灌胃第4、8周末分批处死,取肝脏及股骨头制作病理切片,观察组织学变化。结果:灌胃8周时,A组肝细胞内出现脂肪空泡,小叶中央区受累明显。4组大体形态无明显变化。光镜下,A组病理改变主要集中在股骨头软骨下区,髓内造血组织减少。4周时,脂肪细胞增多,骨小梁面积分数稍降低,与其他3组相比差异无统计学意义(P>0.05);空骨陷窝计数增多,与其他3组相比差异有统计学意义(P<0.01)。8周时,股骨头软骨下骨小梁变细、稀疏甚至断裂,髓内脂肪组织增多。最大脂肪细胞平均直径增大、骨小梁面积分数降低、空骨陷窝计数增多,与其他3组相比差异均有统计学意义(P均<0.01)。结论:鸡可以作为乙醇性股骨头坏死动物模型的研究对象,在马血清致敏条件下可缩短实验周期。

关键词：鸡乙醇股骨头坏死动物模型马血清