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Metal cyanamides: Open-framework structure and energy conversion/storage applications

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Journal of Energy Chemistry 2021年第10期30卷 347-367,I0010页

作者： Bingquan Jia du sun Wei Zhao Fuqiang Huang State Key Laboratory of High Performance Ceramics and Superfine Microstructure Shanghai Institute of CeramicsChinese Academy of SciencesShanghai 200050China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Beijing National Laboratory for Molecular Sciences and State Key Laboratory of Rare Earth Materials Chemistry and Applications College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China

Metal cyanamides are an emerging class of functional materials with potential applications in sustainable energy conversion and storage technologies such as catalysis,supercapacitors,photoluminescence and next-gen ***[NCN]^(2-)as the anion,which is isolobal with[O]^(2-)endows metal cyanamides with similar physicochemical properties as oxides and *** the unique quasI-linear structure and electronic resonance between[N=C=N]^(2-)and[N-C≡N]^(2-)of[NCN]entity bring out superior properties beyond oxides and *** this review,we present research status,challenges,and the recent striking progress on the metal cyanamides in the synthesis and ***,the characteristic structures,physicochemical properties,synthetic methods with corresponding merits/demerits and latest applications in energy conversion and storage of cyanamides are *** detailed outlooks for the new compounds design,morphology manipulation and potential applications are also exhibited.

关键词： Metal cyanamides Structure Properties Synthesis Energy applications

A Second-Order Method for the Electromagnetic Scattering from a Large Cavity

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Numerical Mathematics(Theory,Methods and Applications) 2008年第4期1卷 357-382页

作者： Yingxi Wang Kui du Weiwei sun Department of Mathematics City University of Hong Kong Hong Kong.

In this paper,we study the electromagnetic scattering from a two dimen- sional large rectangular open cavity embedded in an infinite ground plane,which is modelled by Helmholtz *** introducing nonlocal transparent boundary con- ditions,the problem in the open cavity is reduced to a bounded domain problem.A hypersingular integral operator and a weakly singular integral operator are involved in the TM and TE cases,respectively.A new second-order Toeplitz type approximation and a second-order finite difference scheme are proposed for approximating the hyper- singular integral operator on the aperture and the Helmholtz in the cavity,respectively. The existence and uniqueness of the numerical solution in the TE case are established for arbitrary wavenumbers.A fast algorithm for the second-order approximation is pro- posed for solving the cavity model with layered *** results show the second-order accuracy and efficiency of the fast *** important is that the algorithm is easy to implement as a preconditioner for cavity models with more general media.

关键词： Electromagnetic scattering Helmholtz equation fast algorithm Toeplitz matrix second-order method.

Analytical solution and experimental verification for pulsed laser heating process with convective boundary condition

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Science China(Technological Sciences) 2004年第3期47卷 305-319页

作者： HE Yunfeng du Dong sun Zhenguo CHEN Qiang PAN Jiluan Department of Mechanical Engineering Tsinghua University Beijing 100084 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China Department of Mechanical Engineering Tsinghua University Beijing 100084 China

Laser heating process of materials is a complex heat transfer problem involved with laser beam, workpiece and ambience. In particular, variable convective boundary condition has great influence on temperature field distribution and processing quality. However, in the previous studies of temperature field抯 solution, convective boundary condition was either simplified or ignored which affected calculation accuracy and precision. In this paper, an analytical solution for the temperature field with convective boundary condition is obtained using Laplace transforms. Moreover, the dimensionless parameters are identified appropriately. Influence of dimensionless distance (x′), dimensionless time (t ), dimensionless energy absorption at surface (M) and Biot number (Bi) on dimensionless temperature (T′) have been investigated. The results show: as Bi is increased, the effects of the heat convection become more pronounced and make the location of the peak temperature move away from the surface. The method of thermocamera is used to validate the analytical solution for pulsed laser heating process with convective boundary condition and the ideal results are obtained. The present study provides the theoretical basis for improving the understanding of physical process, exact modelling and quality controlling of laser welding and surface treatment.

关键词： laser heating process, heat convection, temperature field, analytical solution, thermography.

Reduced graphene oxide with a highly restored π-conjugated structure for inkjet printing and its use in all-carbon transistors

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Nano Research 2013年第11期6卷 842-852页

作者： Yang Su Jinhong du Dongming sun Chang Liu Huiming Cheng Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences 72 Wenhua RoadShenyang 110016 China

An inkjet-printed graphene film is of great importance for next-generation flexible, low cost and high performance electronic devices. However, due to the limitation of the inkjet printing process, the electrical conductivity of inkjet-printed graphene films is limited to N10 S＇cm-1, and achieving a high conductivity of the printed graphene films remains a big challenge. Here, we develop a ＂weak oxidation- vigorous exfoliation＂ strategy to tailor graphene oxide （GO） for meeting all the requirements of highly conductive inkjet-printed graphene films, including a more intact carbon plane and suitable size. The -conjugated structure of the resulting graphene has been restored to a high degree, and its printed films show an ultrahigh conductivity of -420 S-cm-I, which is tens of times higher than previously reported results, suggesting that, aside from developing a highly efficient reduction method, tuning the GO structure could be an alternative way to produce high quality graphene sheets. Using inkjet-printed graphene patterns as source/drain/gate electrodes, and semiconducting single-walled carbon nanotubes （SWCNTs） as channels, we fabricated an all-carbon field effect transistor which shows excellent performance （an on/off ratio of -104 and a mobility of -8 cm2＂V-l＇s-1） compared to previously reported CNT-based transistors, promising the use of nanocarbon materials, graphene and SWCNTs in printed electronics, especially where high performance and flexibility are needed.

关键词： inkjet printing graphene oxide high conductivity field effect transistor

Proliferation changes in hippocampal neurons following pilocarpine-induced intractable epilepsy in adult rats

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Neural Regeneration Research 2010年第24期5卷 1858-1861页

作者： Lancai Xiong Xuejun Deng Fang Wang Chunling du Shenggang sun Department of Neurology Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430022 Hubei Province China

Epilepsy can lead to the changes in neurons residing in the dentate gyrus. The present study aimed to observe the cell dividing features following epilepsy in adult rat hippocampi, and to study difference in cell proliferation between adult rats with common epilepsy and intractable ***, male, Sprague Dawley rats ware randomly divided into control （n = 8, treatment with normal saline） and three expenmental groups： common epilepsy （n = 33）, intractable epilepsy （n = 11）, and drug-responsive （n = 25）. Pilocarpine （15 mg/kg） was intrapentoneally administered to establish epilepsy in the three experimental groups. Rats that developed epilepsy were treated with chloral hydrate. Rats that did not exhibit spontaneous seizures were enrolled in the common epilepsy group, and rats with spontaneous seizure were included in the spontaneous seizure group. At 6 hours after epileptic attack termination, rats ware intraperitoneally injected with bromodeoxyuridine （Brdu; 50 mg/kg）, an optimal marker forlabeling cell proliferation in vivo, four *** results at 48 hours after Brdu injection indicated that the number of Brdu-positive cells was the highest in the common epilepsy group, followed by the control group,and lastly the intractable group （P 〈 0.01）. In addition, the number of Brdu-positive cells in the common epilepsy group was similar to the drug-responsive group. The present findings demonstrated that intractable epilepsy led to decreased hippocampal neurons in adult rats when compared to common epilepsy.

关键词： intractableepiiepsy hippocampal neurons cell proliferation pilocarpine

Patterns and Cellular Mechanisms of Arm Regeneration in Adult Starfish Asterias rollestoni Bell

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Journal of Ocean University of China 2011年第3期10卷 255-262页

作者： FAN Tingjun FAN Xianyuan du Yutang sun Wenjie ZHANG Shaofeng LI Jiaxin Department of Marine Biology College of Marine Life Sciences Ocean University of China Qingdao 266003 P. R. China

To understand the mechanisms of starfish regeneration, the arms of adult starfish Asterias rollestoni Bell were amputated and their regeneration patterns and cellular mechanisms were *** was found that cells in the outer epidermis and inner parietal peritoneum near the end of the stump began to dedifferentiate 4 d after amputation. The dedifferentiated cells in the outer epidermis proliferated,migrated to the wound site and formed a thickened pre-epidermis which would then re-differentiate gradually into ma-ture *** new parietal peritoneum formed on the coelomic side of wound might be from the curvely elongated parietal peritoneum, resulting from the dedifferentiated and proliferated cells by extension. Afterwards, the proliferated cells made the outer epidermis and inner parietal peritoneum invaginate into the interior dermis and formed blastema-like structures together with induced dedifferentiated dermal cells. Most interestingly, the arm regeneration in A. rollestoni was achieved synchronously by de novo arm-bud formation and growth, and arm-stump elongation. The crucial aspects of arm-bud formation included cell dedifferentiation, proliferation and migration, while those of arm-stump elongation included cell dedifferentiation, proliferation, invagination, and arm-wall-across blastema-like structure formation. The unique pattern and cellular mechanisms of amputated arm regeneration make it easier to understand the rapid regeneration process of adult starfish. This study may lay solid foundations for the research into mo-lecular mechanisms of echinoderm regeneration.

关键词： arm regeneration blastema-like structure adult starfish Asterias rollestoni Bell

单双室电解法合成纳米CeO_2粉体及其表征

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无机材料学报 2008年第1期23卷 87-92页

作者：王涛孙都成新疆大学化学化工学院乌鲁木齐830046

采用直流电解合成法,分别以CeCl_3,Ce(NO_3)_3,CeCl_3-KI溶液为电解液单室制备了纳米CeO_2粉体.经高温焙烧后,TEM和XRD测试表明:粒子基本呈球形,所得产物均为立方晶系CeO_2,粒径分别为20～50nm,30～50nm,20～100nm.同时,使用阴离子交换... 详细信息

采用直流电解合成法,分别以CeCl_3,Ce(NO_3)_3,CeCl_3-KI溶液为电解液单室制备了纳米CeO_2粉体.经高温焙烧后,TEM和XRD测试表明:粒子基本呈球形,所得产物均为立方晶系CeO_2,粒径分别为20～50nm,30～50nm,20～100nm.同时,使用阴离子交换膜的双室电解法电解CeCl_3溶液,发现得到的CeO_2粒径(7～20nm)比单室电解得到的小,分析了造成粒径不同的原因.本工作还对各溶液体系电解形成CeO_2的机理进行了分析.

关键词：电合成 CeO2 单双室机理纳米

Research　on　Techniques　for　Rolling　Exploration　and　Development　and　Application　to　Dongying　Oilfield

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China Oil & Gas 1995年第1期2卷 35-39页

作者： du Xiangyue and sun Longde

ＲｅｓｅａｒｃｈｏｎＴｅｃｈｎｉｑｕｅｓｆｏｒＲｏｌｌｉｎｇＥｘｐｌｏｒａｔｉｏｎａｎｄＤｅｖｅｌｏｐｍｅｎｔａｎｄＡｐｐｌｉｃａｔｉｏｎｔｏＤｏｎｇｙｉｎｇＯｉｌｆｉｅｌｄＤｕＸｉａｎｇｙｕｅａｎｄＳｕｎＬｏｎｇｄ... 详细信息

ＲｅｓｅａｒｃｈｏｎＴｅｃｈｎｉｑｕｅｓｆｏｒＲｏｌｌｉｎｇＥｘｐｌｏｒａｔｉｏｎａｎｄＤｅｖｅｌｏｐｍｅｎｔａｎｄＡｐｐｌｉｃａｔｉｏｎｔｏＤｏｎｇｙｉｎｇＯｉｌｆｉｅｌｄＤｕＸｉａｎｇｙｕｅａｎｄＳｕｎＬｏｎｇｄｅＫｅｙｗｏｒｄｓ：Ｏｉｌｆｉｅｌ...

关键词： Oil field Rolling exploration and development Technique Reserve

Extraction kinetics of phenol with N, N-di (1-methyl-heptyl)acetamide-kerosene using hollow fiber membrane extractor

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Journal of Environmental Sciences 2001年第3期13卷 380-384页

作者： YANG Zhu xian, du Hui fang, sun Xian bo, XIA Ye, ZHOU Zu ming(Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China. 复旦大学上海 200433

Extraction kinetics of phenol with N,N-di(1-methyl-heptyl) acetamide-kerosene using hollow fiber membrane extractor has been studied. The rate regularities and kinetic types of forward and backward extraction were obtained respectively by determining the forward and backward extraction rate under various experimental conditions. The mass transfer mechanism was discussed. Both the forward and backward extraction of phenol might be controlled by diffusion processes, and the diffusion resistance for both forward and backward extraction mainly exists in aqueous phase. In addition, ways to optimize the extraction process of phenol were discussed as well.

关键词： extraction kinetics phenol hollow fiber membrane extractor