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Chemical Research in Chinese Universities 2013年第6期29卷 1050-1054页

作者： yang Min LI Qi-liang wang Ying LIU xiao-yang wang xiao-feng State Key Laboratory of Inorganic Synthesis and Preparative Chemistry Jilin University Changchun 130012 P.R.China

Single crystal Dy3＋ doped YNbO4phosphors were prepared via a high-temperature high-pressure hydrothermal procedure. Under excitation at 270 nm, the Dy3＋-doped YNbO4 phosphor shows bright white emission, which is composed of two strong bands at 492 and 576 nm corresponding to the characteristic 4F9/2→6H15/2 and aF9/2→6H13/2 transitions of Dy3＋, respectively. The dominant band was observed at 352 nm, which corresponds to the 6H15/2→6p7/2 transition of Dy3＋. Nearly white light was achieved at 2ex 270, 310 and 388 nm and the CIE（International Commission on Illumination） values were （0.3135, 0.3421）, （0.3088, 0.3380） and （0.3146, 0.3296）, respectively.

关键词： Dy-YNbO4 Single crystal High-temperature high-pressure Hydrothermal Luminescence

A New Route for the Synthesis of N-Substituted Diketopiperazine Derivatives

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Chinese Chemical Letters 2006年第4期17卷 469-472页

作者： Xi GONG xiao xiao yang De Xin wang Institute of Materia Medica Chinese Academy of Medical Sciences ＆ Peking Union Medical College Beijing 100050

Eight N-substituted diketopiperazines （DKPs） were synthesized by solid-phase protocols. The introduction of iminodiacetic acid （Ida） and followed another a-amino acid residue as the precursor of DKP framework made... 详细信息

关键词： Diketopiperazine iminodiacetic acid solid-phase synthesis.

A Note on the Existence of Fractional f-factors in Random Graphs

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Acta Mathematicae Applicatae Sinica 2014年第3期30卷 677-680页

作者： Jian-sheng CAI xiao-yang wang Gui-ying YAN School of Mathematics and Information Science Weifang University Beijing Anzhen Hospital Capital Medical University Academy of Mathematics and System Science Chinese Academy of Science

Let G ： Gn,p be a binomial random graph with n vertices and edge probability p = p（n）, and f be a nonnegative integer-valued function defined on V（G） such that 0 〈 a ≤ f（x） ≤ b 〈 np- 2√nplogn for every E V（G）. An fractional f-indicator function is an function h that assigns to each edge of a graph G a number h（e） in [0, 1] so that for each vertex x, we have d^hG（x） = f（x）, where dh（x） = ∑ h（e） is the fractional degree xEe ofx inG. Set Eh = {e ： e e E（G） and h（e） ≠ 0}. IfGh isaspanningsubgraphofGsuchthat E（Gh） = Eh, then Gh is called an fractional f-factor of G. In this paper, we prove that for any binomial random graph Gn,p 2 with p 〉 n^-2/3, almost surely Gn,p contains an fractional f-factor.

关键词： random graph probabilistic method f-factor fractional f-factor

Vascular anatomy of inferior mesenteric artery in laparoscopic radical resection with the preservation of left colic artery for rectal cancer

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World Journal of Gastroenterology 2018年第32期24卷 3671-3676页

作者： Ke-Xin wang Zhi-Qiang Cheng Zhi Liu xiao-yang wang Dong-Song Bi Department of General Surgery Qilu Hospital of Shandong University

AIM To investigate the vascular anatomy of inferior mesenteric artery(IMA) in laparoscopic radical resection with the preservation of left colic artery(LCA) for rectal cancer. METHODS A total of 110 patients with rectal cancer who underwent laparoscopic surgical resection with preservation of the LCA were retrospectively reviewed. A 3 D vascular reconstruction was performed before each surgical procedure to assess the branches of the IMA. During surgery, the relationship among the IMA, LCA, sigmoid artery(SA) andsuperior rectal artery(SRA) was evaluated, and the length from the origin of the IMA to the point of branching into the LCA or common trunk of LCA and SA was measured. The relationship between inferior mesenteric vein(IMV) and LCA was also *** Three vascular types were identified in this study. In type A, LCA arose independently from IMA(46.4%, n = 51); in type B, LCA and SA branched from a common trunk of the IMA(23.6%, n = 26); and in type C, LCA, SA, and SRA branched at the same location(30.0%, n = 33). The difference in the length from the origin of IMA to LCA was not statistically significant among the three types. LCA was located under the IMV in 61 cases and above the IMV in 49 cases. CONCLUSION The vascular anatomy of the IMA and IMV is essential for laparoscopic radical resection with preservation of the LCA for rectal cancer. To recognize different branches of the IMA is necessary for the resection of lymph nodes and dissection of vessels.

关键词： Inferior mesenteric artery Left colic artery Rectal cancer Laparoscopic

An Efficient Query Rewriting Approach for Web Cached Data Management

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Wuhan University Journal of Natural Sciences 2006年第1期11卷 122-126页

作者： wang Bin yang xiao-chun wang Guo-ren YU Ge Liu Hui-lin School of Information Science and Engineering Northeastern University Shenyang 110004 Liaoning China

With the internet development, querying data on the Web is an attention problem of involving information from distributed, and often dynamically, related Web sources. Basically, some subqueries can be effectively cached from previous queries or materialized views in order to achieve a better query performance based on the notion of rewriting queries. In this paper, we propose a novel query-rewriting model, called Hierarchical Query Tree, for representing Web queries. Hierarchical Query Tree is a labeled tree that is suit able for representing the inherent hierarchy feature of data on the Web. Based on Hierarchical Query Tree, we use case based approach to determine what the query results should be. The definitions of queries and query results are both re presented as labeled trees. Thus, we can use the same model for representing cases and the medium query results can also be dynamically updated by the user queries. We show that our case-based method can be used to answer a new query based on the combination of previous queries, including changes of requirements and various information sources.

关键词： hierarchical query tree datalog query rewriting

Developmental changes of glutamate acid decarboxylase 67 in mouse brain after hypoxia ischemia

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Neuroscience Bulletin 2006年第1期22卷 47-51页

作者： Fa-Lin XU Chang-Lian ZHU xiao-yang wang Department of Pediatrics the Third Affiliated Hospital of Zhengzhou University Zhengzhou 450052 China

Objective To study the developmental changes of glutamic acid decarboxylase-67 （ GAD-67, a GABA synthetic enzyme） in normal and hypoxic ischemic （HI） brain. Methods C57/BL6 mice on postnatal day （P） 5, 9, 21 and 60, corresponding developmentally to premature, term, juvenile and adult human brain were investigated by using both Western blot and immunohistochemistry methods either in normal condition or after hypoxic ischemic insult. Results The immunoreactivity of GAD67 was up regulated with brain development and significant difference was seen between mature （P21, P60） and immature （P5, P9） brain. GAD67 immunoreactivity decreased in the ipsilateral hemisphere in all the ages after hypoxia ischemia （HI） insult, but, significant decrease was only seen in the immature brain. Double labeling of GAD67 and cell death marker, TUNEL, in the cortex at 8h post-HI in the P9 mice showed that （15.6±7.0）% TUNEL positive cells were GAD67 positive which was higher than that of P60 mice. Conclusion These data suggest that GABAergic neurons in immature brain were more vulnerable to HI insult than that of mature brain.

关键词： glutamic acid decarboxylase brain development hypoxia-ischemia

Elastoplastical analysis on cylinder of different moduli in tension and compression

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Journal of Coal Science & Engineering(China) 2009年第1期15卷 66-71页

作者： wang Wei-ming ZHANG xiao-yan yang Zhao wang Qing-biao College of Civil Engineering and Architecture Shangdong University of Science and Technology Qingdao 266510 China

The constitutive equation was deduced. The results were obtained from theelastic and elastoplastical analysis of the cylinder sample applied with different ratios ofload on both the inner and outer sides and different moduli ratio. The factors affecting thedevelopment of the plastic field of the cylinder with finite radius were shown. The resultsshow that the different moduli ratio is the most important factor in the development of theplastic zone. The slight fluctuation of the ratio will bring multiplied increment of the displacement, which may result in the final destruction of the engineering material.

关键词： cylinder different moduli plastic zone elastoplastical analysis

The New Synthesis of Azo Urea from Substituted Semicarbazide

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Chinese Chemical Letters 1997年第6期8卷 473-474页

作者： xiao yang wang Yu Lu wang Jian Ping LI Cai ’Lan W’ANG Hong wang (Department of Chemistry ,Henan Normal University Xinxiang 453002 ) Department of Chemistry Henan Normal University Xinxiang 453002 China

Using N-bromosuccinimide and pyridine as the oxidation system to dehydrogenate aryl substituted semicarbazide to form azo compounds is described for the first time in this paper. Nine azo compounds have been prepared ... 详细信息

关键词： The New Synthesis of Azo Urea from Substituted Semicarbazide

Bigflow: A General Optimization Layer for Distributed Computing Frameworks

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Journal of Computer Science & Technology 2020年第2期35卷 453-467页

作者： Yun-Cong Zhang xiao-yang wang Cong wang Yao Xu Jian-Wei Zhang xiao-Dong Lin Guang-Yu Sun Gong-Lin Zheng Shan-Hui Yin Xian-Jin Ye Li Li Zhan Song Dong-Dong Miao Baidu Inc. Beijing 100193China Center for Energy-Efficient Computing and Applications Peking UniversityBeijing 100871China

As data volumes grow rapidly, distributed computations are widely employed in data-centers to provide cheap and efficient methods to process large-scale parallel datasets. Various computation models have been proposed to improve the abstraction of distributed datasets and hide the details of parallelism. However, most of them follow the single-layer partitioning method, which limits developers to express a multi-level partitioning operation succinctly. To overcome the problem, we present the NDD (Nested Distributed Dataset) data model. It is a more compact and expressive extension of Spark RDD (Resilient Distributed Dataset), in order to remove the burden on developers to manually write the logic for multi-level partitioning cases. Base on the NDD model, we develop an open-source framework called Bigflow, which serves as an optimization layer over computation engines from most widely used processing frameworks. With the help of Bigflow, some advanced optimization techniques, which may only be applied by experienced programmers manually, are enabled automatically in a distributed data processing job. Currently, Bigflow is processing about 3 PB data volumes daily in the data-centers of Baidu. According to customer experience, it can significantly save code length and improve performance over the intuitive programming style.

关键词： distributed computing programming model optimization technique

A deep learning interatomic potential suitable for simulating radiation damage in bulk tungsten

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Tungsten 2024年第2期6卷 304-322页

作者： Chang-Jie Ding Ya-Wei Lei xiao-yang wang xiao-Lin Li Xiang-Yan Li Yan-Ge Zhang Yi-Chun Xu Chang-Song Liu Xue-Bang Wu Key Laboratory of Materials Physics Institute of Solid State PhysicsHFIPSChinese Academy of SciencesHefei 230031China Science Island University of Science and Technology of ChinaHefei 230026China Laboratory of Computational Physics Institute of Applied Physics and Computational MathematicsBeijing 100088China

So far, it has been a challenge for existing interatomic potentials to accurately describe a wide range of physical properties and maintain reasonable efficiency. In this work, we develop an interatomic potential for simulating radiation damage in body-centered cubic tungsten by employing deep potential, a neural network-based deep learning model for representing the potential energy surface. The resulting potential predicts a variety of physical properties consistent with first-principles calculations, including phonon spectrum, thermal expansion, generalized stacking fault energies, energetics of free surfaces, point defects, vacancy clusters, and prismatic dislocation loops. Specifically, we investigated the elasticity-related properties of prismatic dislocation loops, i.e., their dipole tensors, relaxation volumes, and elastic interaction energies. This potential is found to predict the maximal elastic interaction energy between two 1/2 loops better than previous potentials, with a relative error of only 7.6%. The predicted threshold displacement energies are in reasonable agreement with experimental results, with an average of 128 eV. The efficiency of the present potential is also comparable to the tabulated gaussian approximation potentials and modified embedded atom method potentials, meanwhile, can be further accelerated by graphical processing units. Extensive benchmark tests indicate that this potential has a relatively good balance between accuracy, transferability, and efficiency.

关键词： Machine learning Deep learning Interatomic potential Radiation damage Tungsten