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L^(2)Schrödinger Maximal Estimates Associated with Finite Type Phases in R^(2)

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Acta Mathematica Sinica,English Series 2024年第11期40卷 2809-2839页

作者： Zhuo Ran LI jun yan zhao Teng Fei zhao Department of Mathematics Taizhou UniversityTaizhou225300P.R.China School of Mathematical Sciences Zhejiang Normal UniversityJinhua321004P.R.China School of Mathematics and Physics University of Science and Technology BeijingBeijing100083P.R.China

In this paper,we establish Schrödinger maximal estimates associated with the finite type phaseФ(ξ_(1),ξ_(2)):=ξ_(1)^(m)+ξ_(2)^(m),where m≥4 is an even ***[12],we prove an L2 fractal restriction estimate associated with the surface{(ξ_(1),ξ_(2),Ф(ξ_(1),ξ_(2))):(ξ_(1),ξ_(2)∈[0,]^(2)}as the main result,which also gives results on the average Fourier decay of fractal measures associated with these *** key ingredients of the proof include the rescaling technique from[16],Bourgain-Demeter’sℓ^(2)decoupling inequality,the reduction of dimension arguments from[17]and induction on *** notice that our Theorem 1.1 has some similarities with the results in[8].However,their results do not cover *** arguments depend on the positive definiteness of the Hessian matrix of the phase function,while our phase functions are degenerate.

关键词： Pointwise convergence finite type decoupling reduction of dimension arguments

Design of a low-alloy high-strength and high-toughness martensitic steel

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International Journal of Minerals,Metallurgy and Materials 2013年第8期20卷 733-740页

作者： yan-jun zhao Xue-ping Ren Wen-chao yang Yue Zang School of Materials Science and Engineering Guangxi University School of Materials Science and Engineering University of Science and Technology Beijing

To develop a high strength low alloy （HSLA） steel with high strength and high toughness, a series of martensitic steels were studied through alloying with various elements and thermodynamic simulation. The microstructure and mechanical properties of the designed steel were investigated by optical microscopy, scanning electron microscopy, tensile testing and Charpy impact test. The results show that cementite exists between 500℃ and 700℃, M7C3 exits below 720℃, and they are much lower than the austenitizing temperature of the designed steel. Furthermore, the Ti（C,N） precipitate exists until 1280℃, which refines the microstructure and increases the strength and toughness. The optimal alloying components are 0.19% C, 1.19% Si, 2.83% Mn, 1.24% Ni, and 0.049% Ti; the tensile strength and the V notch impact toughness of the designed steel are more than 1500 MPa and 100 J, respectively.

关键词： high strength steel martensitic steel alloy design thermodynamics alloying elements microstructuremechanical properties

CBN grain wear and its effects on material removal during grinding of FGH96 powder metallurgy superalloy

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Advances in Manufacturing 2023年第1期11卷 21-38页

作者： Ben-Kai Li Biao zhao Wen-Feng Ding Yu-Can Fu Chang-He Li Rong Wang yan-jun zhao National Key Laboratory of Science and Technology on Helicopter Transmission Nanjing University of Aeronautics and AstronauticsNanjing210016People’s Republic of China School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao266525ShandongPeople’s Republic of China Aecc Xi’an Aero-engine Ltd Xi’an710021People’s Republic of China State Key Laboratory of Superabrasives Zhengzhou Research Institute for Abrasive and GrindingZhengzhou450001People’s Republic of China

Grinding with cubic boron nitride(CBN)superabrasive is a widely used method of machining superalloy in aerospace ***,there are some issues,such as poor grinding quality and severe tool wear,in grinding of powder metallurgy superalloy *** addition,abrasive wheel wear is the significant factor that hinders the further application of CBN abrasive *** this case,the experiment of grinding FGH96 with single CBN abrasive grain using different parameters was carried *** wear characteristics of CBN abrasive grain were analyzed by experiment and *** material removal behavior affected by CBN abrasive wear was also studied by discussing the pile-up ratio during grinding *** shows that morphological characteristics of CBN abrasive grain and grinding infeed direction affect the CBN abrasive wear seriously by simulation *** wear,micro break,and macro fracture had an important impact on material removal ***,compared with the single cutting edge,higher pile-up ratio was obtained by multiple cutting edges,which reduced the removal efficiency of the ***,weakening multiple cutting edge grinding on abrasive grains in the industrial production,such as applying suitable dressing strategy,is an available method to improve the grinding quality and efficiency.

关键词： FGH96 powder metallurgy superalloy Single-grain grinding Cubic boron nitride(CBN)abrasive wear Material removal behavior

Scoring system for poor limb perfusion after limb fracture in children

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World Journal of Clinical Cases 2020年第23期8卷 5926-5934页

作者： Ting Zhu Yu Shi Qun Yu yan-jun zhao Wen Dai yan Chen Shun-Sheng Zhang Department of Pediatric Orthopedics Xinhua Hospital Affiliated to Shanghai Jiaotong University School of MedicineShanghai 200092China Zunran Hospital Shanghai 200366China

BACKGROUND Assessment of the vascular status following limb fracture in children is important to evaluate the risk of compartment syndrome,which is an emergency *** To establish a simple and efficient grading scale of limb perfusion in children undergoing surgery for limb *** This retrospective study included pediatric patients with a limb fracture and postoperative plaster fixation who were admitted at The Department of Pediatric Orthopedics of Xinhua Hospital between February 2017 and August *** outcome was poor limb perfusion,which is defined as the postoperative use of *** children were divided into two groups:The normal perfusion group and the poor perfusion *** risk factors have been selected by univariable analyses to establish the Grading Scale for Vascular *** A total of 161 patients were included in the study:85 in the normal perfusion group and 76 in the poor perfusion *** were no significant differences in age,sex,body mass index,ethnicity,cause of fracture,fixation,or site of fracture between the two *** surgery,the skin temperature(P=0.048)and skin color(P<0.001)of the affected limb were significantly different between the two *** relative risk and 95%confidence interval for skin temperature of the affected limb,skin color,and range of motion of the affected limb are 2.18(1.84-2.59),2.89(2.28-3.66),and 2.16(1.83-2.56),*** grading scale was established based on those three factors(score range:0-3 points).Forty-one patients(32.5%)with score 0 had poor limb perfusion;all patients with scores 1(n=32)and 2(n=3)had poor limb perfusion(both 100%).CONCLUSION In children undergoing surgery for limb fracture,a higher Grading Scale for Vascular Status score is associated with a higher occurrence of poor limb perfusion.A prospective study is required for validation.

关键词： Children Fractures Compartment syndromes Evaluation Open fracture reduction Retrospective study

Improving S/N ratio for pre-stack seismic data from western China

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Applied Geophysics 2007年第3期4卷 207-213页

作者： Guo Ping Zhang Wenpo Gao yan zhao jun Gao Shumei Exploration ＆ Development Research Institute Liaohe Oilfield PetroChina Panjin 124010 China

The seismic data from western China is very noisy. Two main reasons are static corrections and low S/N ratio problems. By seismic data processing and study these problems have been effectively solved by iterating the static corrections and improving the S/N ratio for pre-stack seismic data. Suppression and elimination of various other distortions has been implemented as well. Due to the fact that the S/N ratio is improved, the resolution of the seismic data is also improved.

关键词： Static correction low S/N ratio resolution

Anticoagulation with direct thrombin inhibitors during extracorporeal membrane oxygenation

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World Journal of Critical Care Medicine 2019年第6期8卷 87-98页

作者： Barry Burstein Patrick M Wieruszewski yan-jun zhao Nathan Smischney Division of Pulmonary and Critical Care Medicine Mayo ClinicRochesterMN 55905United States Department of Pharmacy Mayo ClinicRochesterMN 55905United States Department of Anesthesia Mayo ClinicRochesterMN 55905United States

Use of extracorporeal membrane oxygenation to support patients with critical cardiorespiratory illness is *** anticoagulation is an essential element in the care of extracorporeal membrane oxygenation *** unfractionated heparin is the most commonly used agent,unfractionated heparin is associated with several unique complications that can be catastrophic in critically ill patients,including heparin-induced thrombocytopenia and acquired antithrombin *** complications can result in thrombotic events and subtherapeutic *** thrombin inhibitors(DTIs)are emerging as alternative anticoagulants in patients supported by extracorporeal membrane *** evidence supports DTIs use as safe and effective in extracorporeal membrane oxygenation patients with and without heparininduced *** review outlines the pharmacology,dosing strategies and available protocols,monitoring parameters,and special use considerations for all available DTIs in extracorporeal membrane oxygenation *** advantages and disadvantages of DTIs in extracorporeal membrane oxygenation relative to unfractionated heparin will be described.

关键词： Extracorporeal membrane oxygenation Anticoagulants Antithrombins Bivalirudin Argatroban Heparin

Erythropoietin reduces apoptosis of brain tissue cells in rats after cerebral ischemia/reperfusion injury:a characteristic analysis using magnetic resonance imaging

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Neural Regeneration Research 2016年第9期11卷 1450-1455页

作者： Chun-juan Jiang Zhong-juan Wang yan-jun zhao Zhui-yang Zhang Jing-jing Tao Jian-yong Ma Department of Radiology Wuxi Second People's Hospital Affiliated to Nanjing Medical University

Some in vitro experiments have shown that erythropoietin （EPO） increases resistance to apoptosis and facilitates neuronal survival follow- ing cerebral ischemia. However, results from in vivo studies are rarely reported. Perfusion-weighted imaging （PWI） and diffusion-weighted imaging （DWI） have been applied successfully to distinguish acute cerebral ischemic necrosis and penumbra in living animals; therefore, we hypothesized that PWI and DWI could be used to provide imaging evidence in vivo for the conclusion that EPO could reduce apoptosis in brain areas injured by cerebral ischemia/reperfusion. To validate this hypothesis, we established a rat model of focal cerebral ischemia/ reperfusion injury, and treated with intra-cerebroventricular injection of EPO （5,000 U/kg） 20 minutes before injury. Brain tissue in the ischemic injury zone was sampled using MRI-guided localization. The relative area of abnormal tissue, changes in PWI and DWI in the ischemic injury zone, and the number of apoptotic cells based on TdT-mediated dUTP-biotin nick end-labeling （TUNEL） were assessed. Our findings demonstrate that EPO reduces the relative area of abnormally high signal in PWI and DWI, increases cerebral blood volume, and decreases the number of apoptotic cells positive for TUNEL in the area injured by cerebral ischemia/reperfusion. The experiment pro- vides imaging evidence in vivo for EPO treating cerebral ischemia/reperfusion injury.

关键词： nerve regeneration nerve protection cerebral ischemia/reperfusion erythropoietin magnetic resonance imaging diffusion-weightedimaging apparent diffusion coefficient perfusion-weighted imaging cerebral blood volume mean transit time apoptosis neural regeneration

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N-甲基吡咯烷酮电解合成的研究

天然气化工—C1化学与化工 2000年第1期25卷 44-46页

作者：闫昭君中国三江航天集团8607厂科技开发部湖北孝感市432100

阐述了N 甲基吡咯烷酮 (NMP)的电解合成过程 ,并在实验的基础上进行了分析和讨论 ,摸索出最佳实验条件 ,以N 甲基丁二酰胺为原料 ,三氯甲烷为萃取剂 ,2 0 % (mass)的硫酸为介质 ,铅电极预处理 2h ,NMP产率达 70 %以上 ,纯度达 97%以上。

关键词：阳离子膜丁二酰亚胺释氢超电压 NMP 电解合成

Construction and Preliminary Analysis of Ovine Oocytes Proteomic 2-DE Map

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Animal Husbandry and Feed Science 2011年第4期3卷 1-3页

作者： LIN Yong-feng ZHANG Yong LI Hong-yan HU jun-jie zhao Xing-xu College of Veterinary Medicine Gansu Agricultural University Lanzhou 730070 China

[Objective] To obtain ovine oocytes 2-dimensional gel electrophoresis （2-DE） maps. [Method] Ovine oocytes were solubilized in lysis buffer, and protein concentrations were measured using the method of Bradford and Ramagli. Then the samples were subjected to two-dimensional polyacrylamide gel electrophoresis. The 2-DE maps of ovine oocytes were analyzed through PDQuest 8.0. [Resait] The Ramagli method could re- flect concentration of oocyte protein more actually and could optimize the quantity of samples to get a 2-DE map with higher quality. The protein concentration measured by the Bradford method was higher than its actual value. [Coclusion] Each 2-DE map loading 700 oocytes is more reasonable.

关键词： Ovine Oocytas Two-dimensional polyacrylamide gel electrophoresis Proteome