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Nickel phosphide on Ni foam as anode and peroxymonosulfate as the chemical oxidizer for effective direct urea fuel cell

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Journal of Environmental Sciences 2021年第12期33卷 84-91页

作者： Jingwei Hao shen zhao Ran Mao Xu zhao Key Laboratory of Drinking Water Science and Technology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China University of Chinese Academy of Sciences Beijing 100049China

The direct urea fuel cell(DUFC) is a low cost and competitive approach for contemporaneous urine or urea-contaminated wastewater treatment and electricity generation. However,the lack of efficient urea oxidation reaction(UOR) electrocatalysts and suitable electron acceptors remains a challenge for practical applications. Here, we developed a DUFC system using Ni2 P@Ni foam as the anode and peroxymonosulfate(PMS) as the chemical *** Ni2 P@Ni foam anode showed a high oxidation activity for UOR with an onset potential of 0.30 V vs. Ag/Ag Cl and Tafel slope of 34.4 m V/dec. PMS with high theoretical potential improved the cell voltage to 1.43 V. A power density of DUFC up to 4.91 m W/cm2 was achieved using PMS at room temperature, which was approximately twice as high as using H2 O2(2.38 m W/cm2). NiII/NiⅢwas the redox active species on the Ni2 P anode in the DUFC process, and NiIIwas electrochemically oxidized to NiⅢ, which reverted to NiII by urea reduction. When real human urine was used as the fuel, a power density of 4.46 m W/cm2 can be achieved at room temperature. This DUFC with high cell performance showed potential application in urea wastewater treatment.

关键词： Direct urea fuel cell(DUFC) Ni2P Peroxymonosulfate Urine

Some projectively flat (α,β)-metrics

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Science China Mathematics 2006年第6期49卷 838-851页

作者： shen Yibing zhao Lili Department of Mathematics Zhejiang University Hangzhou 310028 China Department of Mathematics Zhejiang University Hangzhou 310028 China

In this paper, we study a class of Finsler metrics in the form , where is a Riemannian metric, form, and ∈ and k≠0 are constants. We obtain a sufficient and necessary condition for F to be locally projectively flat and give the non-trivial special solutions. Moreover, it is proved that such projectively flat Finsler metrics with the constant flag curvature must be locally Minkowskian.

关键词： projectively flat, Finsler (α, β)-metrics, flag curvature.

Urban planning construction land standard and its revision based on climate and topography in China

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Journal of Geographical Sciences 2021年第4期31卷 603-620页

作者： XU Yong zhao shen FAN Jie Institute of Geographic Sciences and Natural Resources Research CASBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Urban planning construction land standard is the technical specification for scientifically allocating various types of urban construction land,and it is the basis for drawing up and revising the overall urban planning *** China’s current urban planning construction land standard,many problems exist,such as the gap in the land use control threshold,the lack of regional differences in the climate revision,and failing to consider the topographic *** resolve these problems,this study proposed a step-by-step process framework and quantitative calculation method for the establishment and revision of standards in accordance with the principle of Total-Structure *** setting the conditions,a universal basic standard for construction land was *** analysis was then conducted on the relationship between the basic standard and the selected key indicators,such as urban population size,sunshine spacing coefficient,the width of river valleys or inter-montane basins,and terrain slope,among ***,revised standards were formed for climate conditions,topography,and geomorphologic conditions,which were matched with the basic *** key results are three-fold:(1)The per capita construction land standard of 95 m~2/person can be used as the total indicator of China’s urban planning basic standard,and the corresponding per capita single construction land comprises 32.50%of residential land,7.42%of public management and public service land,22.50%of industrial land,17.50%of transportation facilities,12.50%of green space,and 7.58%of other land-use *** results of the revision of the urban population size indicate that the difference in population size has little effect on the total amount of per capita construction land.(2)The climate revision results of per capita residential land and per capita construction land in major cities reveal that the revised climate value varies greatly between north and south *** revised

关键词： urban planning construction land standard climate revision standard topography revision standard

Triangular domain extension of linear Bernstein-like trigonometric polynomial basis

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Journal of Zhejiang University-Science C(Computers and Electronics) 2010年第5期11卷 356-364页

作者： Wan-qiang shen Guo-zhao WANG Department of Mathematics Zhejiang University Hangzhou 310027 China

In computer aided geometric design(CAGD),the Bernstein-Bézier system for polynomial space including the triangular domain is an important tool for modeling free form *** Bernstein-like bases for other spaces(trigonometric polynomial,hyperbolic polynomial,or blended space) has also been ***,none of them was extended to the triangular *** this paper,we extend the linear trigonometric polynomial basis to the triangular domain and obtain a new Bernstein-like basis,which is linearly independent and satisfies positivity,partition of unity,symmetry,and boundary *** prove some properties of the corresponding surfaces,including differentiation,subdivision,convex hull,and so *** applications are shown.

关键词： Computer aided geometric design(CAGD) Free form modeling Trigonometric polynomial Basis function Bernstein basis Triangular domain

Synthesis and in vitro-Anti-hepatitis B Virus Activities of Several Ethyl 5-Hydroxy-1H-indole-3-carboxylates

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Chemical Research in Chinese Universities 2006年第5期22卷 577-583页

作者： zhao Chun-shen zhao Yan-fang CHAI Hui-fang GONG Ping Liaoning Province Key Laboratory of Innovative Medicine Research and Design Shenyang Pharmaceutical University Shenyang 110016 P. R. China

A series of ethyl 5-hydroxyindole-3-earboxylates 6a-10r was designed and synthesized. The structures of all the compounds were confirmed by IR, ^1H NMR, and MS and their anti-hepatitis B virus （HBV） activities were evaluated in 2.2.15 cells. Among them, compound 7g { ethyl 5-hydroxy-2- [ （ 3-methoxyphenylsulfinyl ） methyl ] -1-methyl-4- [ （4-methylpiperazin-1-yl） methyl ]-1H-indole-3-carboxylate} displays a significant anti-HBV activity, which is more potent than the positive control lamivudine.

关键词： Ethyl 5-hydroxy-1H-indole-3-carboxylates Synthesis Anti-hepatitis B virus activity

Improved HHT and its application in narrowband radar imaging for precession cone-shaped targets

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Journal of Systems Engineering and Electronics 2014年第6期25卷 977-986页

作者： shen zhao Jie Niu Xiang Li Chunjie Qiao College of Mechatronics and Automation National University of Defense Technology Department of Missile Engineering Ordnance Engineering College College of Electronic Science and Engineering National University of Defense Technology

Imaging the spatial precession cone-shaped targets with narrowband radar is a new technical approach in mid-course recognition problem. However, most existing time-frequency methods still have some inevitable deficiencies for extracting microDoppler information in practical applications, which leads to blurring of the image. A new narrowband radar imaging algorithm for the precession cone-shaped targets is proposed. The instantaneous frequency of each scattering point is gained by using the improved Hilbert-Huang transform, then the positions of scattering points in the parameter domain are reconstructed. Numerical simulation and experiment results confirm the effectiveness and high precision of the proposed algorithm.

关键词： improved Hilbert-Huang transform(HHT) instanta-neous frequency narrowband radar imaging precession cone-shaped targets

An AP SoC for a unified architecture

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Chinese Science Bulletin 2010年第35期55卷 4089-4093页

作者： shen XuBang zhao CuiHua Xi'an Microelectronics Research Institute Xi'an 710054 China

An instruction level parallel computing paradigm and a unified architecture for an array processor(AP) on a chip(SoC) are presented in this *** "APU SoC" is short for "an AP SoC for the unified architecture".The MISD/MIMD architecture for instruction level parallel computing is unified with the SIMD architecture for data level parallel *** a result,all the computing can be implemented on an APU *** APU SoC offers the rationale of an array structure for development in current technology,yet simplicity for the hardware(chip) and software(program) parallel *** as a single processor chip can replace many function module chips,the APU SoC can replace the single-core/multi-core/many-core CPU chip for TLP computing and the ASIC/ASSP/FPGA/RC device array chip for Operation Level Parallel computing.

关键词： SoC 架构处理器芯片指令级并行并行计算阵列芯片多功能模块 CPU芯片

On the convergence and improvement of stochastic normalized gradient descent

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Science China(Information Sciences) 2021年第3期64卷 105-117页

作者： shen-Yi zhao Yin-Peng XIE Wu-Jun LI National Key Laboratory for Novel Software Technology Department of Computer Science and TechnologyNanjing University

Non-convex models, like deep neural networks, have been widely used in machine learning applications. Training non-convex models is a difficult task owing to the saddle points of models. Recently,stochastic normalized gradient descent(SNGD), which updates the model parameter by a normalized gradient in each iteration, has attracted much attention. Existing results show that SNGD can achieve better performance on escaping saddle points than classical training methods like stochastic gradient descent(SGD).However, none of the existing studies has provided theoretical proof about the convergence of SNGD for non-convex problems. In this paper, we firstly prove the convergence of SNGD for non-convex ***, we prove that SNGD can achieve the same computation complexity as SGD. In addition, based on our convergence proof of SNGD, we find that SNGD needs to adopt a small constant learning rate for convergence guarantee. This makes SNGD do not perform well on training large non-convex models in practice. Hence, we propose a new method, called stagewise SNGD(S-SNGD), to improve the performance of SNGD. Different from SNGD in which a small constant learning rate is necessary for convergence guarantee,S-SNGD can adopt a large initial learning rate and reduce the learning rate by stage. The convergence of S-SNGD can also be theoretically proved for non-convex problems. Empirical results on deep neural networks show that S-SNGD achieves better performance than SNGD in terms of both training loss and test accuracy.

关键词： non-convex problems stochastic normalized gradient descent computation complexity

Clinical application of magnetically controlled capsule gastroscopy in gastric disease diagnosis: recent advances

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Science China(Life Sciences) 2018年第11期61卷 1304-1309页

作者： Zhuan Liao Wenbin Zou zhao-shen Li Department of Gastroenterology Changhai Hospital the Second Military Medical University

Magnetically controlled capsule gastroscopy(MCCG) is a novel system primarily used for the diagnosis of gastric disease. It consists of an endoscopic capsule with magnetic material inside, external guidance magnet equipment, data recorder and computer workstation. Several clinical trials have demonstrated that MCCG is comparable in accuracy in diagnosing gastric focal disease when compared to conventional gastroscopy. Further clinical studies are needed to test the diagnostic accuracy and improve the functioning of MCCG. This novel MCCG system could be a promising alternative for screening for gastric diseases,with the advantages of no anesthesia required, comfort and high acceptance across populations.

关键词： magnetically controlled capsule endoscopy gastric diseases screening conventional gastroscopy diagnostic accuracy