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Ideal class groups and their subgroups of real quadratic fields

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Science China Mathematics 1997年第9期40卷 909-916页

作者：张贤科 lawrence C.Washington Department of Mathematics Tsinghua UniversityBeijing 100084China Department of Mathematics University of MarylandCollege ParkMD 20742USA

A necessary and sufficient condition is given for the ideal class group h( m } of a real quadratic field Q (m)to contain a cyclic subgroup of order *** criteria satisfying the condition are also *** eight types of such fields are proved to have this property,*** with m=(zn+t+12)+4t(with t|zn-1),which contains the well-known fields with m=4zn+1 and m=z2n+4 as special cases.

关键词： real quadratic field ideal class group class number.

Clinical features and treatment outcomes of endogenous Klebsiella endophthalmitis:a 12-year review

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International Journal of Ophthalmology(English edition) 2020年第12期13卷 1933-1940页

作者： Chun Yue Mak Mary ho lawrence Pui-leung Iu helena Pui-yee Sin Li Jia Chen Grace Lui Marten Erik Brelen Alvin Lerrmann young Department of Ophthalmology and Visual Sciences Prince of Wales HospitalNew TerritoriesHong KongChina Department of Ophthalmology and Visual Sciences the Chinese University of Hong KongNew TerritoriesHong KongChina Division of Infectious Diseases Department of Medicine and Therapeuticsthe Chinese University of Hong KongNew TerritoriesHong KongChina

AIM:To identify the clinical features and treatment outcomes of endogenous Klebsiella pneumoniae endophthalmitis and investigate prognostic factors of poor visual ***:The clinical records of all patients diagnosed with endogenous Klebsiella endophthalmitis between January 2007 to December 2018 in Prince of Wales hospital,hong Kong,China were retrospectively *** ophthalmological examination findings were recorded in the case note,including visual acuity testing,slit-lamp examination,indirect ophthalmoscopy and B-scan ultrasonography if media opacity precluded fundus ***:A total of 18 eyes in 14 patients were *** involvement was noted in 4 patients(28.6%).hepatobiliary sepsis was the source in 9 patients(64.3%).Culture of intraocular fluid was positive in 5 out of 18 eyes(27.8%).Mortality was noted in 2 patients(14.3%).Mean final visual acuity was 20/*** out of 16 eyes had total loss of sight(37.5%)and 3 eyes required evisceration(18.8%).Multivariate linear regression revealed poor presenting visual acuity(P=0.031)and lack of fundus view due to vitritis(P=0.02)as prognostic factors of poor visual ***:Visual outcome of endogenous Klebsiella endophthalmitis is *** presenting visual acuity and lack of fundus view predict poor visual *** index of suspicion for endophthalmitis is important in Klebsiella sepsis patients with complaints of ocular *** screening is recommended in noncommunicable patients with Klebsiella sepsis.

关键词： Klebsiella pneumoniae endogenous endophthalmitis screening liver abscess sepsis

Stability of a Generalized Quadratic Functional Equation in Schwartz Distributions

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Acta Mathematica Sinica,English Series 2009年第9期25卷 1459-1468页

作者： Jae-young ChUNG Department of Mathematics Kunsan National University Kunsan 573-701 Republic of Korea

We consider the hyers-Ulam stability problem of the generalized quadratic functional equationuoA＋voB-2woP1 - 2ko P2 =0, which is a distributional version of the classical generalized quadratic functional equation f（... 详细信息

关键词： hyers-Ulam stability generalized quadratic functional equation distribution heat kernel

Some New Inverse-type hilbert-Pachpatte Integral Inequalities

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Acta Mathematica Sinica,English Series 2004年第1期20卷 57-62页

作者： young ho KIM Department of Applied Mathematics Changwon National UniversityChangwon 641-773Korea

In this paper, some new generalizations of inverse type hilbert-Pachpatte integral inequalities are proved. The results of this paper reduce to those of Pachpatte (1998, J. Math. Anal. Appl. 226, 166–179) and Zhao an... 详细信息

关键词： hilbert’s double integral inequality h(?)lder integral inequality Jensen’s inequality Power mean inequality

Ground-state mass of ^(22)Al and test of state-of-the-art ab initio calculations

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Chinese Physics C 2024年第3期48卷 72-78页

作者：孙铭泽于越王新鹏王猛李健国张玉虎 K.Blaum 陈祖毅陈瑞九邓涵宇付超义葛文文黄文嘉焦红扬李红蕙李宏福罗胤芳廖挺 YuALitvinov 司敏帅鹏史金阳王茜邢元明徐星徐瑚珊许甫荣袁琪 T.Yamaguchi 颜鑫亮杨建成原有进周小红周旭张敏曾奇 CAS Key Laboratory of high Precision Nuclear Spectroscopy Institute of Modern PhysicsChinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China Max-Planck-Institut für Kernphysik Saupfercheckweg 169117 HeidelbergGermany GSI helmholtzzentrum für Schwerionenforschung Planckstraße 164291 DarmstadtGermany Advanced Energy Science and Technology Guangdong Laboratory Huizhou516007China State Key Laboratory of Nuclear Physics and Technology School of PhysicsPeking UniversityBeijing 100871China Department of Physics Saitama UniversitySaitama 338-8570Japan School of Nuclear Science and Engineering East China University of TechnologyNanchang 330013China

The ground-state mass excess of the T_(z)=−2 drip-line nucleus ^(22)Al is measured for the first time as 18103(10)keV using the newly-developed Bρ-defined isochronous mass spectrometry method at the cooler storage ring in *** new mass excess value allowed us to determine the excitation energies of the two low-lying 1+states in ^(22)Al with significantly reduced uncertainties of 51 *** compared to the analogue states in its mirror nucleus ^(22)F,the mirror energy differences of the two 1^(+)states in the ^(22)Al-^(22)F mirror pair are determined to be−625(51)keV and−330(51)*** excitation energies and mirror energy differences are used to test the state-of-the-art ab initio valence-space in-medium similarity renormalization group calculations with four sets of interactions derived from the chiral effective field *** mechanism leading to the large mirror energy differences is investigated and attributed to the occupation of theπs_(1/2) orbital.

关键词： nuclear mass Bρ-defined IMS mirror energy difference ab initio VS-IMSRG calculations chiral interactions

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Insouciance

英语学习 2020年第3期 21-27页

作者： lawrence 徐浩不详北京外国语大学

My balcony is on the east side of the hotel,and my neighbours on the right are a Frenchman,white-haired,and his white-haired wife;my neighbours on the left are two little white-haired English *** we are all mortally s... 详细信息

关键词：学习笔记 Insouciance

国际二语自我调节学习研究二十年回顾:基于文献计量与范围综述的融通方法

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浙江大学学报（人文社会科学版） 2024年第4期54卷 145-159页

作者：滕琳杨玉鑫张雨阳 [英]内森·托马斯张军浙江大学外国语学院浙江杭州310058 伦敦大学学院应用语言学中心伦敦WC1H 0AL 奥克兰大学教育学院奥克兰92019

创新运用文献计量与范围综述相融合的方法,揭示出近二十年来国际二语自我调节学习研究的现状及其不足。在理论层面,自我调节学习存在概念界定不清及相关术语使用混淆两大问题。此外,现有研究以社会认知理论为主导,缺乏从多元理论视角对... 详细信息

创新运用文献计量与范围综述相融合的方法,揭示出近二十年来国际二语自我调节学习研究的现状及其不足。在理论层面,自我调节学习存在概念界定不清及相关术语使用混淆两大问题。此外,现有研究以社会认知理论为主导,缺乏从多元理论视角对自我调节学习的深入探究。在研究群体上,多聚焦高等教育阶段的外语学习者,而对不同年龄段和文化背景下学习者的自我调节机制了解不足。在研究话题上,主要集中在写作任务情景,而对听力、阅读、口语及词汇等其他语言技能的自我调节学习过程探讨不足。在研究方法上,主要是问卷调查和访谈,缺乏对自我调节学习过程和能力发展的历时研究。因此,未来研究需要厘清自我调节学习的概念内涵;拓宽理论视角;扩大研究对象范围;全面探讨不同语言技能的自我调节学习过程;开展实验和历时性追踪研究,运用多种方法收集过程性数据,以便深入了解二语自我调节学习的过程和发展轨迹,为二语教学提供更为有益的指导。

关键词：自我调节学习二语/外语文献计量范围综述可视化分析

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Ex situ aging effect on sulfonated poly(ether ether ketone) membrane:hydration-dehydration cycling and hydrothermal treatment

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Journal of Energy Chemistry 2022年第7期31卷 583-592,I0014页

作者： Seung-young Choi Kyeong Sik Jin Polymer&Materials Chemistry Department of ChemistryLund UniversitySE-22100Sweden Center for hydrogen·Fuel Cell Research Korea Institute of Science and Technology(KIST)Seoul 02792Republic of Korea Pohang Accelerator Laboratory Pohang University of Science and Technology(POSTECH)PohangKyungbuk 37673Republic of Korea

Prolonged hydrothermal treatment for sulfonated poly(ether ether ketone) membranes induces mechanical degradation and developing hydrophilic-hydrophobic phase separation, simultaneously. The enhanced phase separation provides incremental proton conductivity to the membranes, whereas mechanical degradation drastically reduces device stability. On this basis, we describe here the effects of two different ex situ aging processes on sulfonated poly(ether ether ketone) membranes: hydrationdehydration cycling and prolonged hydrothermal treatment. Both aged membranes exhibited enhanced phase separation under the hydrated conditions, as characterized by small angle X-ray ***, when the aged membranes were dried again, the nanostructure of the membranes aged via the hydration-dehydration cycling was recoverable, whereas that of the membranes aged via prolonged hydrothermal treatment was irreversible. Furthermore, the two differently aged membranes showed clear differences in thermal, mechanical, and electrochemical properties. Finally, we implemented both aged membranes in fuel cell application. The sample aged via hydration-dehydration cycling maintained its improved cell performance, whereas the sample aged via hydrothermal treatment showed drastically reduced cell performance after durability test for 50 h.

关键词： Sulfonated poly(ether ether ketone) humidity cycle test Ex situ aging Proton exchange membrane Fuel cell

Stabilized sub-grain and nano carbides-driven 1.2 GPa grade ultra-strong CrMnFeCoNi high-entropy alloy additively manufactured by laser powder bed fusion

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Journal of Materials Science & Technology 2022年第22期117卷 8-22页

作者： young-Kyun Kim Kee-Ahn Lee Department of Materials Science and Engineering Inha UniversityIncheon 22212Republic of Korea Korea Institute of Materials Science(KIMS) Changwon 51508Republic of Korea

high-entropy alloys(hEAs)with interstitial atoms that are produced by additive manufacturing have gained intensive interest in the materials science community because of their suitability for constructing high-strength net-shape ***,a strategy to additionally enhance the strength of selective laser melted carbon-containing hEAs was *** as-built carbon-containing hEAs(C_(x)(Cr_(20)Mn_(20)Fe_(20)Co_(20)Ni_(20))_(100-x)(x=0.5 at.%,1.0 at.%,and 1.5 at.%))contain supersaturated carbon,and the extent of supersaturation increases as the carbon content *** subjected to aging treatment at 650°C for 1 h,the microstructure of the three alloys did not change at the grain ***,the microstructure at the sub-grain scale changed markedly,and these changes influenced the tensile properties and deformation *** particular,the tensile strength of aged 1.5C-hEA at 650°C was∼1.2 GPa at room temperature,which is higher than those reported for CrMnFeCoNi ***,the main deformation mechanism changed from deformation twinning to dislocation-mediated slip,resulting in much higher strain hardening capacity after the aging *** work led to the development of an alternative promising method that involves tailoring the microstructure,to enhance the mechanical properties of additively manufactured metallic materials that contain interstitial atoms.

关键词： Selective laser melting high-entropy alloy Carbon contents Aging Microstructure evolution Tensile property Deformation mechanism