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Synthesis and Performance of Polyurethane Coated Urea as Slow/controlled Release Fertilizer

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Journal of Wuhan University of Technology(Materials Science) 2012年第1期27卷 126-129页

作者： LI Qingshan WU Shu RU Tiejun WANG Limin xing guangzhong WANG Jinming State Key Laboratory of Metastable Materials Science and Technology Yanshan UniversityQinhuangdao 066004China Sino-Arab Chemical Fertilizer Co..Ltd.(SACF) Qinhuangdao 066003China

Polyurethane coated urea slow/controlled release fertilizer was prepared based on urea granules, isocyanate, polyols and paraffin. Isocyanate reacted with polyols to synthesize the polyurethane skin layer on urea granules surface. Paraffin serves as a lubricant during syntheses of polyurethane skin layers. The structure and nutrient release characteristics of the polyurethane skin layers were investigated by FTIR, SEM and TG. Urea nitrogen slow-release behavior of the polyurethane coated urea was tested. The experimental results indicated that compact and dense polyurethane skin layers with a thickness of 10-15 lam were formed on urea surface, the urea nitrogen slow-release time can reach 40-50 days. Paraffin proves to play a key role in inhibiting water to penetrate into urea, but excessive addition would decrease the polyurethane crosslinking density.

关键词： polyurethane elastomer coated urea slow / controlled release fertilizer paraffin

A MODIFIED EDGE-ORIENTED SPATIAL INTERPOLATION ALGORITHM FOR CONSECUTIVE BLOCKS ERROR CONCEALMENT

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Journal of Electronics(China) 2007年第2期24卷 214-217页

作者： Fu Wei xing guangzhong Department of Communication and Electronic Engineering Yanshan University Qinhuangdao 066004 China

This paper proposes a low-complexity spatial-domain Error Concealment (EC) algorithm for recovering consecutive blocks error in still images or Intra-coded (I) frames of video sequences. The proposed algorithm works with the following steps. Firstly the Sobel operator is performed on the top and bottom adjacent pixels to detect the most likely edge direction of current block area. After that one-Dimensional (1D) matching is used on the available block boundaries. Displacement between edge direction candidate and most likely edge direction is taken into consideration as an important factor to improve stability of 1D boundary matching. Then the corrupted pixels are recovered by linear weighting interpolation along the estimated edge direction. Finally the interpolated values are merged to get last recovered picture. Simulation results demonstrate that the proposed algorithms obtain good subjective quality and higher Peak Signal-to-Noise Ratio (PSNR) than the methods in literatures for most images.

关键词： Error concealment Spatial. interpolation Boundary matching Sobel operator

Preparation of nanometer perovskite-type oxide La_(0.8)Sr_(0.2)MnO_3 by organic solvent sol-gel method and capability testing

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Rare Metals 2008年第2期27卷 131-133页

作者： HU Jie SHAO Guangjie HUANG Hao xing guangzhong State Key Laboratory of Metastable Materials Science ＆ Technology Yanshan University Qinhuangdao 066004 China Department of Environment and Chemistry Yanshan University Qinhuangdao 066004 China

A perovskite-type oxide, La0.8Sr0.2MnO3, was synthesized by the organic solvent sol-gel method. The desired metal cations were chelated in a solution by using citric acid as the chelating agent and absolute ethanol as the solvent. The thermal decomposition of the metal carboxylate precursor gels was studied by thermogravimetric/differential thermal analyzer （TG/DTA） and the products derived from calcining the gels were characterized by X-ray diffraction （XRD） and transmission electronic microscope （TEM）. The polarization curves were acquired on an electrochemical workstation （LK98） and the discharge curves were acquired on a testing instrument of batteries （DC-5）, with a constant current discharge, less than 120 mA/cm^2. The results revealed that the nanometer perovskite-type powder with lesser particle size could be achieved with an organic solvent and had a better catalytic activity.

关键词： nanometer-materials perovskite organic solvent catalytic activity

Effects of high pressure on the microstructure and hardness of a Cu-Zn alloy

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Rare Metals 2008年第5期27卷 541-544页

作者： ZHAO Juna LIU Lin YANG Jingru PENG Guirong LIU Jianhua ZHANG Ruijuna xing guangzhong State Key Laboratory of Metastable Materials Science and Technology Yanshan University Qinhuangdao 066004 China Department of Basic Medical Tangshan Vocational Technology College Tangshan 063000 China Department of Information and Electromechanical Engineering Hebei Building Material College of Professional Technology Qinhuangdao 066004 China

The microstructure of a Cu-Zn alloy treated under different high pressures was investigated by means of metallographic, scanning electron microscope （SEM）, energy dispersive spectrometer （EDS）, and X-ray diffraction （XRD）, and the hardness of the Cu-Zn alloy was also measured. The results show that the ct phase with a smaller grain size, different shapes, and random distribution appears in the Cu-Zn alloy during the solid-state phase transformation generation in the temperature range of 25-750℃ and the pressure range of 0-6 GPa. The amount of residual α phase in the microstructure decreases and then increases with increasing pressure. Under a high pressure of 3 GPa, the least volume fraction of residual a phase was obtained, and under a high pressure of 6 GPa, the changes of the microstructure of the Cu-Zn alloy were not obvious. In addition, high pressure can increase the hardness of the Cu-Zn alloy, but it cannot generate any new phase.

关键词： Cu-Zn alloy microstructure hardness high pressure

Cambricon-QR:a sparse and bitwise reproducible quantized training accelerator

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High Technology Letters 2024年第1期30卷 52-60页

作者：李楠 ZHAO Yongwei ZHI Tian LIU Chang DU Zidong HU xing LI Wei ZHANG Xishan LI Ling SUN guangzhong School of Computer Science and Technology University of Science and Technology of ChinaHefei 230026P.R.China State Key Laboratory of Processors Institute of Computing TechnologyChinese Academy of SciencesBeijing 100086P.R.China Cambricon Tech.Ltd Beijing 100191P.R.China Institute of Software Chinese Academy of SciencesBeijing 100086P.R.China

Quantized training has been proven to be a prominent method to achieve deep neural network training under limited computational *** uses low bit-width arithmetics with a proper scaling factor to achieve negligible accuracy ***-Q is the ASIC design proposed to efficiently support quantized training,and achieves significant performance ***,there are still two caveats in the ***,Cambricon-Q with different hardware specifications may lead to different numerical errors,resulting in non-reproducible behaviors which may become a major concern in critical ***,Cambricon-Q cannot leverage data sparsity,where considerable cycles could still be squeezed *** address the caveats,the acceleration core of Cambricon-Q is redesigned to support fine-grained irregular data *** new design not only enables acceleration on sparse data,but also enables performing local dynamic quantization by contiguous value ranges(which is hardware independent),instead of contiguous addresses(which is dependent on hardware factors).Experimental results show that the accuracy loss of the method still keeps negligible,and the accelerator achieves 1.61×performance improvement over Cambricon-Q,with about 10%energy increase.

关键词： quantized training sparse accelerator Cambricon-QR

钙钛矿型La_(1-x)Sr_xMnO_3纳米薄膜的制备及其光催化性能

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稀有金属材料与工程 2010年第1期39卷 173-176页

作者：胡婕邵光杰黄浩邢广忠燕山大学河北秦皇岛066004

采用溶胶-凝胶法和浸渍提拉技术在载玻片基底上制备出钙钛矿型La1-xSrxMnO3纳米薄膜;采用TG/DTA技术分析前驱体凝胶的热分解历程;利用AFM观察薄膜的形貌特征;通过XRD进行物相分析,并计算其晶粒尺寸。结果表明,La1-xSrxMnO3薄膜在600℃形... 详细信息

采用溶胶-凝胶法和浸渍提拉技术在载玻片基底上制备出钙钛矿型La1-xSrxMnO3纳米薄膜;采用TG/DTA技术分析前驱体凝胶的热分解历程;利用AFM观察薄膜的形貌特征;通过XRD进行物相分析,并计算其晶粒尺寸。结果表明,La1-xSrxMnO3薄膜在600℃形成,为钙钛矿结构,其平均晶粒尺寸为10.349nm。采用该薄膜对多种水溶性染料进行光催化降解试验的结果表明,掺杂后该类纳米薄膜有较好的光催化效果,当x=0.2时光催化效果最好。

关键词：钙钛矿溶胶-凝胶纳米薄膜:光催化

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地学专家系统的知识化数据模式研究

地球信息科学 2006年第1期8卷 61-66,78页

作者：付炜邢广忠燕山大学信息学院通信与电子工程系秦皇岛066004 新疆大学电子科学与信息工程学院

介绍了地学专家系统的知识化数据结构的设计原理与实现方法,采用知识表示的框架网络结构描述地理环境的实体单元,将各级专家知识的表示以指针链接,形成了由知识到语义的框架网络。采用了基于知识的扩展R-F 关系数据模式进行专家知识的表... 详细信息

介绍了地学专家系统的知识化数据结构的设计原理与实现方法,采用知识表示的框架网络结构描述地理环境的实体单元,将各级专家知识的表示以指针链接,形成了由知识到语义的框架网络。采用了基于知识的扩展R-F 关系数据模式进行专家知识的表示,并讨论了系统知识库的组织结构和推理机的设计原理。该数据结构可以实现地理实体及其相互关系的完整性描述,并使系统知识库的操作简便易行,保证了推理机的实现。以乌鲁木齐河流域为试验区,阐述了流域土地合理利用规划决策专家知识的表示方法,以及专家知识表示的基本规则和系统专家知识的组织方式。此外,还讨论了系统推理机推理规则的设计原理与组织方法及推理算法。

关键词：知识表示框架网络结构知识化数据模式

AN APPLIED RESEARCH ON APPROACH OF DYADIC WAVELET TRANSFORM FOR REMOTE SENSING IMAGE EDGE DETECTION

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Journal of Electronics(China) 2006年第4期23卷 535-538页

作者： Fu Wei xing guangzhong Hou Lantian Qin Qiming Wang Wenjun Department of Communicaton ＆ Electricity Engineering Yanshan University Qinhuangdao 066004 China Remote Sensing Institute Peking University Beijing 100871 China

In the edge detection of Remote Sensing (RS) image, the useful detail losing and the spurious edge often appear. To solve the problem, the authors uses the dyadic wavelet to detect the edge of surface features by combining the edge detecting with the multi-resolution analyzing of the wavelet transform. Via the dyadic wavelet decomposing, the RS image of a certain appropriate scale is obtained, and the edge data of the plane and the upright directions are respectively figured out, then the gradient vector module of the surface features is worked out. By tracing them, the authors get the edge data of the object, therefore build the RS image which obtains the checked edge. This method can depress the effect of noise and examine exactly the edge data of the object by rule and line. With an experiment of an RS image which obtains an airport, the authors certificate the feasibility of the application of dyadic wavelet in the object edge detection.

关键词： Dyadic wavelet transform Edge detection and tracking of Remote Sensing (RS) Object recognition

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共析珠光体钢在冷轧过程中的组织变化

金属学报 2005年第3期41卷 267-270页

作者：孙淑华熊毅傅万堂邢广忠古原忠牧正志燕山大学材料科学与工程学院秦皇岛066004 京都大学工学部材料工学研究科

用SEM、TEM及XRD等方法研究了共析钢中珠光体经40％-90％的冷轧变形后所产生的显徽组织变化.按渗碳体形态特点,变形珠光体组织可分为以下3种类型: (1)不规则弯曲片层型,即变形后的渗碳体与轧制面呈大角度偏离且不规则弯曲的珠光体. (2... 详细信息

用SEM、TEM及XRD等方法研究了共析钢中珠光体经40％-90％的冷轧变形后所产生的显徽组织变化.按渗碳体形态特点,变形珠光体组织可分为以下3种类型: (1)不规则弯曲片层型,即变形后的渗碳体与轧制面呈大角度偏离且不规则弯曲的珠光体. (2)带有剪切带的粗大片层型,即被渗碳体剪切带分开且变形轻微的珠光体. (3)精细片层型,即与轧制方向平行排列、片间距细小且渗碳体严重变形的珠光体.精细片层区域的比例随着轧制压下率的提高而增大.此外,重度冷轧变形还引起渗碳体严重塑性变形和部分溶解.

关键词：高碳钢珠光体冷轧渗碳体溶解