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LaGa-based bulk metallic glasses

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Chinese Physics B 2017年第1期26卷 91-96页

作者： Lin-Zhi Zhao rong-Jie Xue Wei-hua Wang hai-yang Bai Institute of Physics Chinese Academy of Sciences Beijing 100190 China

We report the formation of La Ga-based bulk metallic glasses. Ternary La–Ga–Cu glassy rods of 2–3 mm in diameter can be easily formed in a wide composition range by the conventional copper mold casting method. With minor addition of extra elements such as Co, Ni, Fe, Nb, y, and Zr, the critical diameter of the full glassy rods of the La–Ga–Cu matrix can be markedly enhanced to at least 5 mm. The characteristics and properties of these new La Ga-based bulk metallic glasses with excellent glass formation ability and low glass transition temperature are model systems for fundamental issues investigation and could have some potential applications in micromachining field.

关键词： bulk metallic glasses glass forming ability La–Ga–Cu alloys

Surgical and interventional management of complications caused by acute pancreatitis

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World Journal of Gastroenterology 2014年第37期20卷 13412-13423页

作者： Feza y Karakayali Baskent University Faculty of MedicineDepartment of General Surgery

Acute pancreatitis is one of the most common gastrointestinal disorders worldwide. It requires acute hospitalization, with a reported annual incidence of 13 to 45 cases per 100000 persons. In severe cases there is persistent organ failure and a mortality rate of 15% to 30%, whereas mortality of mild pancreatitis is only 0% to 1%. Treatment principles of necrotizing pancreatitis and the role of surgery are still controversial. Despite surgery being effective for infected pancreatic necrosis, it carries the risk of long-term endocrine and exocrine deficiency and a morbidity and mortality rate of between 10% to 40%. Considering high morbidity and mortality rates of operative necrosectomy, minimally invasive strategies are being explored by gastrointestinal surgeons, radiologists, and gastroenterologists. Since 1999, several other minimally invasive surgical, endoscopic, and radiologic approaches to drain and debride pancreatic necrosis have been described. In patients who do not improve after technically adequate drainage, necrosectomy should be performed. When minimal invasive management is unsuccessful or necrosis has spread to locations not accessible by endoscopy, open abdominal surgery is recommended. Additionally, surgery is recognized as a major determinant ofoutcomes for acute pancreatitis, and there is general agreement that patients should undergo surgery in the late phase of the disease. It is important to consider multidisciplinary management, considering the clinical situation and the comorbidity of the patient, as well as the surgeons experience.

关键词： Severe acute pancreatitis Complications Necrosectomy Percutaneous drainage Endoscopy Laparoscopy

Fast rectangular matrix multiplication and some applications

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Science China Mathematics 2008年第3期51卷 389-406页

作者： Victor y PAN Department of Mathematics and Computer Science.Lehman College City University of New York BronxNew York 10468 USA

We study asymptotically fast multiplication algorithms for matrix pairs of arbitrary dimensions, and optimize the exponents of their arithmetic complexity bounds. For a large class of input matrix pairs, we improve the known exponents. We also show some applications of our results: (i) we decrease from O(n 2 + n 1+o(1)logq) to O(n 1.9998 + n 1+o(1)logq) the known arithmetic complexity bound for the univariate polynomial factorization of degree n over a finite field with q elements; (ii) we decrease from 2.837 to 2.7945 the known exponent of the work and arithmetic processor bounds for fast deterministic (NC) parallel evaluation of the determinant, the characteristic polynomial, and the inverse of an n × n matrix, as well as for the solution to a nonsingular linear system of n equations; (iii) we decrease from O(m 1.575 n) to O(m 1.5356 n) the known bound for computing basic solutions to a linear programming problem with m constraints and n variables.

关键词： rectangular matrix multiplication asymptotic arithmetic complexity bilinear algorithm polynomial factorization over finite fields 68Q25 11y16

Research in effects of environmentally-friendly carbon black masterbatch powder rubber

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Research in effects of environmentally-friendly carbon black...

Adaptation of real earthquake records for their reproduction by a shaking table with limited stroke

第八届中国功能材料及其应用学术会议

作者： WEI Xu-ling GONG Guang-bi LIANG Tao WANG rong-min Key Laboratory of Eco-Environment-Related Polymer Materialls of Ministry of Education College of Chemistry and Chemical EngineeringNorthwest Normal University Petrochemical Research Institute of PetroChina Company Limited

ISBN: (纸本)9783037859698

To prepare carbon black masterbatch powder rubber,the process of direct agglomerate powderzation has been *** the main factors have been studied,such as the dosage of isolation agent and coagulation agent,ph and water binder ratio of condensed system,environment-friendly antiaging agent,temperature and stirring *** results show that the best operational condition is as following:the appropriate dosage ofisolation agent is 2.0

关键词： carbon black masterbatch powder rubber environmental protection type antiaging agent,powder ratio

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Earthquake Engineering and Engineering Vibration 2010年第4期9卷 493-502页

作者： B Blostotsky y Ribakov G Agranovich Ariel University Center of Samaria

Shaking tables with moving platforms are widely used in laboratory testing of structural models and full-sized devices. In most cases, the platform＇s movement should reproduce real ground acceleration records. however, the stroke of the platform, required for reproduction of real records, is usually rather large. This limitation does not allow an accurate realization of the ground motion by the shaking table. Commonly, in order to overcome this problem, original records are modified, which causes a significant change in the acceleration records＇ spectra. That is why structural responses to the original and to the modified records are different. A new method for modification of original acceleration records is proposed, in which the original record is corrected by an additional artificial one that changes the shaking platform＇s displacement. The corrected record is obtained as a sequence of impulses, The magnitude and duration of each impulse, as well as their location on the time scale, are obtained by an optimization procedure. The optimization is implemented according to a performance index, aimed to minimize the influence of the correcting acceleration record on the specmam of the original one. The proposed method has higher reproduction accuracy, compared to other known methods. Its effectiveness is demonstrated by comparison of response spectra and dynamic behaviors of three multi-story structures subjected to natural and modified seismic excitations.

关键词： shaking table platform stroke earthquake record reproduction scaling optimization

AlTiN and AlTiON-coated hot work tool steels for tooling in steel thixoforming

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中国有色金属学会会刊：英文版 2010年第S3期20卷 1022-1028页

作者： y.BIROL D.ISLER Materials Institute Marmara Research CentreGebzeKocaeliTurkey Department of Metallurgy and Materials Engineer ing Istanbul Technical UniversityIstanbulTurkey

X32CrMoV33 hot work tool steel samples coated with AlTiN and AlTiON were submitted to thermal cycling under conditions that approximate thixoforming of steels and to sliding wear tests at 750 ℃,measured to be the cavity surface temperature shortly after the steel slurry is forced into the thixoforming *** and AlTiON coatings provide adequate protection against oxidation of the tool steel substrate,but fail to avoid thermal fatigue *** is attributed to the extensive softening of the substrate,the thermal expansion mismatch between the hot work tool steel and the coatings and residual compressive stresses inherited from the deposition *** impact of AlTiN and AlTiON coatings on the high temperature wear resistance,on the other hand,is *** improved wear resistance is attributed to the stable,protective surface oxide films.

关键词： thixoforming physical vapor deposition coating tooling steels thermal fatigue wear

Understanding the structural evolution and Na^＋ kinetics in honeycomb-ordered O＇3-Na3Ni2SbO6 cathodes

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Nano Research 2018年第6期11卷 3258-3271页

作者： Peng-Fei Wang hu-rong yao ya you yong-Gang Sun ya-Xia yin yu-Guo Guo Chinese Academy of Science (CAS) Key Laboratory of Molecular Nanostructure and Nanotechnology Beijing National Laboratory for Molecular Science CAS Research/Education Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy o Sciences Beijing 100190 China School of Chemistry and Chemical Engineering University of Chinese Academy of Sciences Beijing 100049 China

The development of new sodium ion battery （SIB） cathodes with satisfactory performance requires an in-depth understanding of their structure-function relationships, to rationally design better electrode materials. In this work highly ordered, honeycomb-layered Na3Ni2SbO6 was prepared to elucidate the structural evolution and Na~ kinetics during electrochemical desodiation/sodiation processes. Structural analysis involving in situ synchrotron X-ray diffraction （XRD） experiments, electrochemical performance measurements, and electrochemical characterization （galvanostatic intermittent titration technique, GITT） methods were used to obtain new insights into the reaction mechanism controlling the （de）intercalation of sodium into the host NaB-xNi2SbO6 structure. Two phase transitions occur （initial O＇3 phase → intermediate P＇3 phase→final O1 phase） upon Na^＋ extraction; the partial irreversible O＇3-P＇3 phase transition is responsible for the insufficient cycling stability. The fast Na^＋ mobility （average 10^-12 cm^2·s^-1） in the interlayer, high equilibrium voltage （3.27 V）, and low voltage polarization （50 mV） establish the linkage between kinetic advantage and a good rate performance of the cathode. These new findings provide deep insight into the reaction mechanism operating in the honeycomb cathode; the present approach could be also extended to investigate other materials for SIBs.

关键词： sodium-ion batteries (SIB) cathode honeycomb-ordered structural evolution Na^+ kinetics

Pulmonary artery aneurysm protruding into the bronchus as an endobronchial mass:A case report

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World Journal of Clinical Cases 2023年第28期11卷 6792-6796页

作者： Min Li Wen-ye Zhu rong-rong Wu Le Wang Meng-Ting Mo Shi-Nan Liu Dong-yi Zhu Zhuang Luo Department of Respiratory and Critical Care Medicine The First Affiliated Hospital of Kunming Medical UniversityKunming 650032Yunnan ProvinceChina Department of Pharmacy The First Affiliated Hospital of Kunming Medical UniversityKunming 650032Yunnan ProvinceChina Department of Radiology The First People’s Hospital of Yunnan Province/Affiliated Hospital of Kunming University of Science and TechnologyKunming 650034Yunnan ProvinceChina

BACKGROUND Pulmonary artery(PA)aneurysms are usually diagnosed radiographically and present as small or large lesions resembling inflammation or a neoplasm on chest *** has rarely been reported as an endobronchial *** SUMMARy We report the case of a 64-year-old man who presented with recurrent *** revealed a tumorous protrusion blocking the right middle lobe bronchus,which was confirmed to be a PA aneurysm using endobronchial ultrasound bronchoscopy and computed tomography *** Although endobronchial PA aneurysms are rare,bronchoscopists need to add this lesion to the list of endobronchial masses for which a biopsy is to be assiduously avoided.

关键词： Pulmonary artery aneurysm Endobronchial mass Endobronchial ultrasound bronchoscopy Computed tomography angiography Case report

hydrocarbon expulsion model and resource potential evaluation of high-maturity marine source rocks in deep basins:Example from the Ediacaran microbial dolomite in the Sichuan Basin,China

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Petroleum Science 2022年第6期19卷 2618-2630页

作者： Wen-yang Wang Xiong-Qi Pang ya-Ping Wang Zhang-Xin Chen Chang-rong Li Xin-hua Ma State Key Laboratory of Lithospheric Evolution Institute of Geology and GeophysicsChinese Academy of SciencesBeijing 100029China State Key Laboratory of Petroleum Resources and Prospecting China University of Petroleum(Beijing)Beijing 102249China College of Geosciences China University of Petroleum(Beijing)Beijing 102249China Research Institute of Exploration and Development Petro China Southwest Oil&Gas Field CompanyChengduSichuan 610041China Chemical and Petroleum Engineering Schulich School of EngineeringUniversity of CalgaryCalgary T2N 1N4Canada School of Earth and Space Sciences Peking UniversityBeijing 100871China Research Institute of Petroleum Exploration and Development(RIPED) Petro ChinaBeijing 100083China

hydrocarbon expulsion features and resource potential evaluation of source rocks are crucial for the petroleum ***-maturity marine source rocks have not exhibited a hydrocarbon expulsion mode owing to the lack of low-maturity source rocks in deep petroliferous *** considered the Ediacaran microbial dolomite in the Sichuan Basin,the largest high-maturity marine gas layer in China,to exhibit a method that quantitatively characterizes the hydrocarbon expulsion of high-maturity marine source *** experiment of fluid inclusion,rock pyrolysis,and vitrinite reflectance(Ro)of 119 microbial dolomite core samples obtained from the Dengying Formation were performed.A hydrocarbon expulsion model of high-maturity source rock was established,and its resource potential was *** results showed that the Ediacaran microbial dolomite in the Sichuan Basin is a good source rock showing vast resource *** hydrocarbon expulsion threshold is determined to be vitrinite reflectance at 0.92%.The hydrocarbon expulsion intensities in the geologic history is high with maximum of 1.6×10^(7)t/km^(2).The Ediacaran microbial dolomite expelled approximately 1.008×10^(12)t of hydrocarbons,and the recoverable resource was 1.5×10^(12)m^(3).The region can be categorized into areasⅠ,Ⅱ,Ⅲ,andⅣ,in decreasing order of hydrocarbon expulsion *** with a higher hydrocarbon expulsion intensity have a lower drilling risk and should be prioritized for exploration in the orderⅠ>Ⅱ>Ⅲ>Ⅳ.Two areas,northern and central parts of Ediacaran in the Sichuan Basin,were selected as prospects which had the drilling priority in the future gas *** production data of 55 drilled wells verified the high reliability of this *** model in this study does not require low-maturity samples and can be used for evaluating high-maturity marine source rocks,which has broad applicability in deep basins worldwide.

关键词： Deep petroliferous basin Overmatured source rocks hydrocarbon expulsion model Resource evaluation Sichuan basin