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calibration of an analyzing magnet using the ¹²c(d, p₀)¹³c nuclear reaction with a thick carbon target

NUcLEAR INSTRUMENTS & METHODS IN PHYSIcS RESEARcH SEcTION B-BEAM INTERAcTIONS WITH MATERIALS AND ATOMS 2017年第PartA期406卷 38-41页

作者： Andrade, E. canto, c. E. Rocha, M. F. Univ Nacl Autonoma Mexico Inst Fis Apartado Postal 20-364 Mexico City 01000 DF Mexico Inst Politecn Nacl ESIME Z ALM Zacatenco Mexico City 07738 DF Mexico

The absolute energy of an ion beam produced by an accelerator is usually determined by an electrostatic or magnetic analyzer, which in turn must be calibrated. Various methods for accelerator energy calibration are extensively reported in the literature, like nuclear reaction resonances, neutron threshold, and time of flight, among others. This work reports on a simple method to calibrate the magnet associated to a vertical 5.5 MV Van de Graaff accelerator. The method is based on bombarding with deuteron beams a thick carbon target and measuring with a surface barrier detector the particle energy spectra produced. The analyzer magnetic field is measured for each spectrum and the beam energy is deduced by the best fit of the simulation of the spectrum with the SIMNRA code that includes c-12(d,p(0))c-13 nuclear cross sections. (c) 2017 Elsevier B.V. All rights reserved.

关键词： c NR c-12(d,p(0))c-13 Analyzing magnet calibration

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The HEcT Type Ubiquitin Ligase NEDL2 Is Degraded by Anaphase-promoting complex/cyclosome (APc/c)-cdh1, and Its Tight Regulation Maintains the Metaphase to Anaphase Transition

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JOURNAL OF BIOLOGIcAL cHEMISTRY 2013年第50期288卷 35637-35650页

作者： Lu, Li Hu, Shaohua Wei, Rongfei Qiu, Xiao Lu, Kefeng Fu, Yesheng Li, Hongchang Xing, Guichun Li, Dong Peng, Ruiyun He, Fuchu Zhang, Lingqiang Beijing Inst Radiat Med Beijing Proteome Res Ctr State Key Lab Prote Beijing 100850 Peoples R China Dalian Med Univ Inst Canc Stem Cells Dalian 116023 Liaoning Provin Peoples R China Beijing Univ Technol Coll Life Sci & Bioengn Beijing 100124 Peoples R China Beijing Inst Radiat Med Dept Expt Pathol Beijing 100850 Peoples R China Tsinghua Univ Dept Biol Sci & Biotechnol Beijing 100084 Peoples R China

Background: NEDL2 is a member of the HEcT type ubiquitin ligase NEDD4 family, but its function remains largely unknown. Results: NEDL2 is degraded by APc/c-cdh1 during mitotic exit and regulates metaphase to anaphase transition. conclusion: NEDL2 appears to dynamically modulate regulation of mitosis. Significance: Our data provide a novel substrate of APc/c-cdh1 and reveal an additional protein by which HEcT type ubiquitin ligase can regulate mitosis. NEDD4-like ubiquitin ligase 2 (NEDL2) is a HEcT type ubiquitin ligase. NEDL2 enhances p73 transcriptional activity and degrades ATR kinase in lamin misexpressed cells. compared with the important functions of other HEcT type ubiquitin ligase, there is less study concerning the function and regulation of NEDL2. Using primary antibody immunoprecipitation and mass spectrometry, we identify a list of potential proteins that are putative NEDL2-interacting proteins. The candidate list contains many of mitotic proteins, especially including several subunits of anaphase-promoting complex/cyclosome (APc/c) and cdh1, an activator of APc/c. cdh1 can interact with NEDL2 in vivo and in vitro. cdh1 recognizes one of the NEDL2 destruction boxes (R(740)GSL(743)) and targets it for degradation in an APc/c-dependent manner during mitotic exit. Overexpression of cdh1 reduces the protein level of NEDL2, whereas knockdown of cdh1 increases the protein level of NEDL2 but has no effect on the NEDL2 mRNA level. NEDL2 associates with mitotic spindles, and its protein level reaches a maximum in mitosis. The function of NEDL2 during mitosis is essential because NEDL2 depletion prolongs metaphase, and overexpression of NEDL2 induces chromosomal lagging. Elevated expression of NEDL2 protein and mRNA are both found in colon cancer and cervix cancer. We conclude that NEDL2 is a novel substrate of APc/c-cdh1 as cells exit mitosis and functions as a regulator of the metaphase to anaphase transition. Its overexpression may contribute to tumorigenesis.

关键词： cell cycle Mitosis Protein Degradation Tumor Ubiquitin Ligase APc c

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Influence of crop residue management, cropping system and N fertilizer on soil N and c dynamics and sustainable wheat (Triticum aestivum L.) production

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SOIL & TILLAGE RESEARcH 2009年第2期104卷 233-240页

作者： Bakht, Jehan Shafi, Mohammad Jan, Mohammad Tariq Shah, Zahir NW Frontier Prov Agr Univ Inst Biotechnol & Genet Engn Peshawar Pakistan NW Frontier Prov Agr Univ Dept Agron Peshawar Pakistan NW Frontier Prov Agr Univ Dept Soil & Environm Sci Peshawar Pakistan

Management of N is the key for sustainable and profitable wheat production in a low N soil. We report results of irrigated crop rotation experiment, conducted in the North West Frontier Province (NWFP), Pakistan, during 1999-2002 to evaluate effects of residue retention, fertilizer N application and mung bean (Vigna radiata) on crop and N yields of wheat and soil organic fertility in a mung bean-wheat sequence. Treatments were (a) crop residue retained (+residue) or (b) removed (-residue), (c) 120 kg N ha(-1) applied to wheat, (d) 160 kg N ha(-1) to maize or (e) no nitrogen applied. The cropping system was rotation of wheat with maize or wheat with mung bean. The experiment was laid out in a spit plot design. Postharvest incorporation of crop residues significantly (p < 0.05) increased the grain and straw yields of wheat during both years. On average, crop residues incorporation increased the wheat grain yield by 1.31 times and straw yield by 1.39 times. The wheat crop also responded strongly to the previous legume (mung bean) in terms of enhanced grain yield by 2.09 times and straw yield by 2.16 times over the previous cereal (maize) treatment. Application of fertilizer N to previous maize exerted strong carry over effect on grain (1.32 times) and straw yield (1.38 times) of the following wheat. Application of N fertilizer to current wheat produced on average 1.59 times more grain and 1.77 times more straw yield over the 0 N kg ha(-1) treatment. The N uptake in wheat grain and straw was increased 1.31 and 1.64 times by residues treatment, 2.08 and 2.49 times by mung bean and 1.71 and 1.86 times by fertilizer N applied to wheat, respectively. The soil mineral N was increased 1.23 times by residues, 1.34 times by mung bean and 2.49 times by the application of fertilizer N to wheat. Similarly, the soil organic c was increased 1.04-fold by residues, 1.08 times by mung bean and 1.00 times by the application of fertilizer N. We concluded that retention of residues, appli

关键词： crop residues cropping system N c Wheat

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Urchin-like MnO/c microspheres as high-performance lithium-ion battery anode

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IONIcS 2021年第4期27卷 1423-1428页

作者： Zhang, Lei Shen, Lian Liu, Yangai Suo, Guoquan China Univ Geosci Sch Mat Sci & Technol Natl Lab Mineral Mat Beijing Key Lab Mat Utilizat Nonmetall Minerals & Beijing 100083 Peoples R China Shaanxi Univ Sci & Technol Sch Mat Sci & Engn Xian 710021 Peoples R China

Manganese oxide (MnO) is prospective as anode material for lithium-ion batteries (LIBs) due to its low insertion voltage and high reversible capacity. Here, urchin-like MnO microspheres with carbon coating (u-MnO/c) are synthesized through hydrothermal method, and its lithium storage performance is investigated. The unique urchin-like structures of u-MnO/c endow it high surface area which provides sufficient contact with electrolyte. The carbon coating can effectively suffer volume change of u-MnO during charge/discharge process. Meanwhile, the carbon coating can effectively improve the conductivity of u-MnO-based anode. Due to the above features, u-MnO/c delivers high initial capacity of 845 mAh g(-1), and an obvious activation process is observed at the beginning of the cycles thanks to the abundant invasion of the electrolyte into u-MnO/c. The large capacity of 723 mAh g(-1) can still be achieved after 80 cycles. This work provides a promising guide for designing high-performance LIBs electrode materials.

关键词： Lithium ion batteries MnO c composite Microsphere

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DESIGN OF A SAFE STRING LIBRARY FOR c

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SOFTWARE-PRAcTIcE & EXPERIENcE 1994年第6期24卷 565-578页

作者： NARAYANAN, AK AVL List GmbH Kleiststrasse 48 A-8020 Graz Austria

The c programming language provides no bounds-checking for arrays. As a result, string operations provided in the standard c library are potentially unsafe. A solution, in the form of a safe string library, is presented. The design goals are safety, inter-operability with existing safe and unsafe routines, debugging help and ease of use.

关键词： BOUNDS-cHEcKING STRING c SAFETY

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A drawing and multi-representational computer environment for beginners' learning of programming using c: Design and pilot formative evaluation

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cOMPUTERS & EDUcATION 2010年第1期54卷 69-87页

作者： Kordaki, Maria Univ Patras Dept Comp Engn & Informat Rion 26500 Greece

This paper presents both the design and the pilot formative evaluation study of a computer-based problem-solving environment (named LEcGO: Learning Environment for programming using c using Geometrical Objects) for the learning of computer programming using c by beginners. In its design, constructivist and social learning theories were taken into account. The general design has taken into consideration models of the learning process and subject matter as well as potential learner behaviour in dealing with fundamental tasks. The main emphasis has been placed on the role of: (a) multiple external representations in student learning, (b) motivation, through performing problem-solving activities taken from the familiar and meaningful context of drawing, using simple geometrical objects, (c) the active participation of students in their own learning by using hands-on experience, (d) appropriate feedback on the actions taken by students, to aid their self-correction, and (e) holistic, activity-based, multi-media, multi-representational and multi-layered content for the learning of basic concepts of programming using c. LEcGO was pilot evaluated in the field through a qualitative and comparative study where nine 12th grade (18-year-old) students participated. In fact, students faced three similar yet not identical sets of four tasks across three learning environments, namely;paper and pencil (p-p), Turbo c and LEcGO. The data emerging from this field evaluation study indicates that students gain better results within LEcGO than in both the p-p environment and the typical programming environment of Turbo c, while performing similar activities. (c) 2009 Elsevier Ltd. All rights reserved.

关键词： Programming c Interactive learning environments Multiple representation systems Secondary education

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Polymer-derived co2Si@Sic/c/SiOc/SiO2/co3O4nanoparticles: Microstructural evolution and enhanced EM absorbing properties

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JOURNAL OF THE AMERIcAN cERAMIc SOcIETY 2020年第12期103卷 6764-6779页

作者： Wu, Yongfeng Zhong, Yunwang Guan, Yan Gu, chong Shao, Guangyu Shi, Benyang Su, Zhiming Xu, Binbin Yu, Zhaoju Liu, Anhua Xiamen Univ Coll Mat Key Lab High Performance Ceram Fibers Minist Educ Xiamen 361005 Peoples R China Xiamen Univ Shenzhen Res Inst Shenzhen Peoples R China Peking Univ Coll Chem & Mol Engn Beijing Peoples R China Xiamen Univ Coll Chem & Chem Engn Xiamen Peoples R China Xiamen Univ Fujian Key Lab Adv Mat Xiamen Peoples R China

In this work, porous core-shell structured co2Si@Sic/c/SiOc/SiO2/co(3)O(4)nanoparticles were fabricated by a polymer-derived ceramic approach. The in situ formation of mesopores on the shell, microstructural, and phase evolution of resulting nanoparticles were investigated in detail. The obtained nanoparticles-paraffin composites possess a very low minimum reflection coefficient (Rcmin) -60.9 dB, broad effective absorption bandwidth 3.50 GHz in the X-band and 15.5 GHz in the whole frequency range (from 2.5 to 18 GHz). The results indicate outstanding electromagnetic wave (EMW) absorbing performance among all the reported cobalt-based nanomaterials, due to the reasons as follows: (a) The unique core-shell structure as well as complex phase composition of Sic/c/SiOc/SiO2/co(3)O(4)in the shell, result in a large number of heterogeneous interfaces in the nanoparticles;(b) Nanoparticles have both dielectric and magnetic loss;(c) Mesopores in the shell prolong the propagation path of EMW, thereby increasing the absorption/reflection ratio of EMWs. Thanks to the material structure design, the resulting core-shell structured cobalt-containing ceramic nanoparticles have great potential for thin and high-performance EMW absorbing materials applied in harsh environment.

关键词： co2Si@Sic c SiOc SiO2 co(3)O(4)nanoparticles electromagnetic wave absorbing properties microstructural evolution polymer-derived ceramics porous core-shell structure

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Acid Hydrolysis to Provide the Potential for Rice-Husk-Derived c/SiO₂ composites for Lithium-Ion Batteries

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JOURNAL OF ELEcTRONIc MATERIALS 2021年第8期50卷 4426-4432页

作者： Ma, Lijie Liu, Li Liu, Xiaoyang Li, Yixin Feng, Yi Tian, Yumei chao, Yimin Zhu, Yanchao Wang, Xiaofeng Jilin Univ Coll Chem State Key Lab Inorgan Synth & Preparat Chem 2699 Qianjin St Changchun 130012 Peoples R China Northeast Normal Univ Dept Chem Changchun 130024 Peoples R China Univ East Anglia Sch Chem Norwich Res Pk Norwich NR4 7TJ Norfolk England

As major waste materials in the rice milling industry, rice husks (RHs) have potential industrial applications. In this work, acid solutions were used to extract high-value-added polysaccharide components (hemicellulose and cellulose) from RHs to obtain sugar residues (SRs) for comprehensive utilization. The SRs were converted into c/SiO2 composites after carbonization and ball-milling. The c/SiO2 composites with crystalline cellulose content in the precursor possessed desirable electrochemical properties when tested as an anode material for lithium-ion batteries (LIBs), including cycle performance, initial coulombic efficiency (IcE) and electrical impedance. Meanwhile, a high reversible specific capacity of 553 mAh g(-1) was maintained after 100 cycles at a current density of 0.1 A g(-1). This method can be used to turn biomass into a potentially valuable anode material with desirable electrochemical properties for LIBs.

关键词： Rice husks sugar residues c SiO2 composites lithium-ion battery

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ORR properties of S-modified co₃O₄@S-g-c₃N₄/c catalyst in alkaline electrolyte

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IONIcS 2021年第6期27卷 2545-2551页

作者： Dong, Xuewei Wang, Dongchao Qiu, Zhongyu Xuan, Jiaping Huang, Naibao Dalian Jiaotong Univ Sch Environm & Chem Engn Dalian Peoples R China Dalian Maritime Univ Dept Mat Sci & Engn Dalian Peoples R China

Developing high-efficiency and low-cost electrocatalysts for oxygen reduction reaction (ORR) is one of the key objectives for fuel cells. In this work, S-modified co3O4@S-g-c3N4/c catalyst was prepared by combining pyrolysis with ultrasonic method. Transmission electron microscopy analysis indicated that the obtained catalyst had a core-shell structure, which used co3O4 as its core and 1.5-nm-thick S-interspersed g-c3N4 encapsulated co3O4 as shell. When the ratio of S to g-c3N4 was 1:3, the as-prepared catalyst co3O4@ S-g-c3N4/c exhibited positive onset potential and higher limiting diffusion current density of 4.00 mA cm(-2) @0.8V, which was 10 and 37% higher than that of co3O4@g-c3N4/c and co3O4/c, respectively. After 2000 cV cycles, the catalyst also showed good durability.

关键词： Fuel cell co3O4 ORR catalyst co3O4@ S-g-c3N4 c

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Influence of the fiber orientation on 3D c/c-Sic composite material and its formation mechanism of the machining surface

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INTERNATIONAL JOURNAL OF ADVANcED MANUFAcTURING TEcHNOLOGY 2022年第7-8期118卷 2725-2743页

作者： Li, Wei Long, Gui Shi, Feng Zhou, Shenlei Yin, Jia Yang, Jun Hunan Univ Coll Mech & Vehicle Engn Changsha 410082 Hunan Peoples R China Hunan Univ Natl Engn Technol Res Ctr High Efficiency Grindin Changsha 410082 Hunan Peoples R China Natl Univ Def Technol Coll Intelligent Sci Changsha 410073 Hunan Peoples R China Chinese Acad Sci Shanghai Inst Opt & Fine Mech Shanghai 201800 Peoples R China

carbon/carbon (c/c)-Sic composite materials attained much attention due to its unique properties like immense thermal conductivity, high corrosion, and abrasive resistance. Few scholars have systematically studied the grinding machinability of 3D c/c-Sic composite material. In this paper, the grinding experiment of 3D c/c-Sic composite material was carried out with a resin-bonded diamond grinding wheel. The effect of machining conditions on the grinding force, micromorphology, surface quality, and residual stress was studied, and the material removal mechanism was analyzed in-depth aimed at the three typical fiber orientations. The result shows that the surface roughness of different fiber areas follows the order: 90 degrees fiber > 0 degrees fiber > Normal fiber. The fiber's orientation showed a significant effect on the mechanism of material removal. The residual thermal stress of c/c-Sic composite material increases from 32.25 to 207.43 MPa during the grinding process. Polishing the ground surface not only can remove the crack layer and residual stress layer but also can introduce residual compressive stress layer, which can effectively enhance the material strength. The 3D c/c-Sic composite material removal process is distinct from the composite material 2D c/c-Sic and the traditional brittle material. The main removal of c/c-Sic composite material is recognized as brittle fracture mode. Because of the different mechanical properties of carbon fiber, Sic matrix, and the pyrocarbon interface, the damage of material during grinding is asynchronous. The present work provides a comprehensive understanding for processing 3D c/c-Sic composite material parts with high quality.

关键词： c c-Sic Grinding carbon fiber Surface roughness The material removal mechanism

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