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Effects of CeO_2 on the XPS valence band spectra of coal under the combustion initialization stage at 400℃

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International Journal of Minerals,Metallurgy and Materials 2013年第4期20卷 338-344页

作者： Cheng-lin Qi jian-liang Zhang Chao Ma Gen-sheng Feng zhong-ping Song State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing Shougang Research Institute of Technology

In order to get the catalytic mechanism of CeO2 on graphite and coal at 400℃, the morphologies of coal, graphite, and CeO2 before and after combustion were analyzed through X-ray photoelectron spectroscopy （XPS）. It is found that the particle size of coal is mostly between 11.727 and 64.79 μm, while the particle size of CeO2 is between 1.937 and 11.79 μm. The agglomeration of coal and CeO2 can be seen by scanning electron microscopy （SEM） after reaction. XPS results show that with the addition of CeO2, the intensity of binding energy gets stronger, but there is no energy peak transition. Comparing the character of coal with and without the addition of CeO2, it can be seen that the C C bond fractures first at 400℃, while the C-H energy-band takes electrons at the same time to be far away from the Fermi level, and the O 2s, O 2p, and C sp hybrid orbitals are all excited. Adding CeO2 can enhance the activity of the whole coal. In addition, through XPS analysis, combined with the oxygen transfer theory and the electron transfer theory, the catalytic mechanism of CeO2 for pulverized coal combustion could be obtained.

关键词： coal combustion cerium oxide valence bands catalysis binding energy X-ray photoelectron spectroscopy pulverized fuel

Growth and Major Nutrient Concentrations in Brassica campestris Supplied with Different NH4^＋/NO3 Ratios

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Journal of Integrative Plant Biology 2007年第4期49卷 455-462页

作者： Fu-Cang Zhang Shao-zhong Kang Fu-sheng Li jian-Hua Zhang Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education Northwest A & F University Yangling 712100 China College of Water Resources and Civil Engineering China Agricultural University Beijing 100083 China College of Agriculture Guangxi University Nanning 530005 China Department of Biology Hong Kong Baptist University Hong Kong SAR China

In the present study, we investigated whether growth and main nutrient ion concentrations of cabbage （Brassica campestris L.） could be increased when plants were subjected to different NH4^＋/NO3- ratios. Cabbage seedlings were grown in a greenhouse in nutrient solutions with five NH4^＋/NO3- ratios （1：0; 0.75：0.25; 0.5：0.5; 0.25：0.75; and 0：1）. The results showed that cabbage growth was reduced by 87% when the proportion of NH4^＋-N in the nutrient solution was more than 75% compared with a ratio NH4^＋/NO3- of 0.5：0.5 35 d after transplanting, suggesting a possible toxicity due to the accumulation of a large amount of free ammonia in the leaves. When the NH4＋/NO3- ratio was 0.5：0.5, fresh seedling weight, root length, and H2PO4- （P）, K^＋, Ca^2＋, and Mg^2＋ concentrations were all higher than those in plants grown under other NH4^＋/NO3- ratios. The nitrate concentration in the leaves was the lowest in plants grown at 0.5： 0.5 NH4^＋/NO3-. The present results indicate that an appropriate NH4^＋/NO3- ratio improves the absorption of other nutrients and maintains a suitable proportion of N assimilation and storage that should benefit plant growth and the quality of cabbage as a vegetable.

关键词： cabbage (Brassica campestris), N nutrition NH4^+/NO3- ratio plant growth plant nutrition.

Alternate Furrow Irrigation: A Practical Way to Improve Grape Quality and Water Use Efficiency in Arid Northwest China

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Journal of Integrative Agriculture 2013年第3期12卷 509-519页

作者： DU Tai-sheng KANG Shao-zhong YAN Bo-yuan ZHANG jian-hua Center for Agricultural Water Research in China China Agricultural University School of Life Sciences and State Key Laboratory of Agrobiotechnology The Chinese University of Hong Kong

Field experiments were conducted for two years to investigate the benefits of alternate furrow irrigation on fruit yield, quality and water use efficiency of grape （Vitis vinifera L. cv. Rizamat） in the arid region of Northwest China. Two irrigation treatments were included, i.e., conventional furrow irrigation （CFI, two root-zones were simultaneously irrigated during the consecutive irrigation） and alternate partial root-zone furrow irrigation （AFI, two root-zones were alternatively irrigated during the consecutive irrigation）. Results indicate that AFI maintained similar photosynthetic rate （Pn） but with a reduced transpiration rate when compared to CFI. As a consequence, AFI improved water use efficiency based on evapotranspiration （WUEEr, fruit yield over water consumed） and irrigation （WUE~, fruit yield over water irrigated） by 30.0 and 34.5%, respectively in 2005, and by 12.7 and 17.7%, respectively in 2006. AFI also increased the edible percentage of berry by 2.91-4.79% significantly in both years. Vitamin C （Vc） content content of berry was increased by 25.6-37.5%, and tritrated acidity （TA） was reduced by 9.5-18.1% in AFI. This resulted in an increased total soluble solid content （TSS） to TA ratio （TSS/TA） by 11.5-16.7% when compared to CFI in both years. Our results indicate that alternate furrow irrigation is a practical way to improve grape fruit quality and water use efficiency for irrigated crops in arid areas.

关键词： alternate furrow irrigation partial root-zone irrigation fruit yield water use efficiency fruit quality grape(Fitis vinifera L. )

REVIEW OF SOME RESEARCHES ON NANO-AND SUBMICRON BROWNIAN PARTICLE-LADEN TURBULENT FLOW

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Journal of Hydrodynamics 2012年第6期24卷 801-808页

作者： LIN jian-zhong HUANG Li-zhong China Jiliang University Department of Mechanics Zhejiang University

The study of nano- and submicron Brownian particle-laden turbulent flow has wide industrial applicability and hence has received much attention. The purpose of the present paper is to provide and review some researches in this field. The topics are related to the universality, particularity, complexity and importance of nano- and submicron Brownian particle-laden turbulent flow, the models of particle general dynamical equation, the collision behavior of particles. Finally, several open research issues are identified.

关键词： particle-laden flow nano-particle submicron particle Brownian turbulence

Analysis of Temperature Field and Thermal Crown of Roll During Hot Rolling by Simplified FEM

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Journal of Iron and Steel Research International 2006年第6期13卷 27-30,48页

作者： GUO zhong-feng LI Chang-sheng XU jian-zhong LIU Xiang-hua WANG Guo-dong State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 Liaoning China

Thermal crown of roll is an important factor, which affects strip profile. It is necessary to analyze the temperature field and thermal crown of roll for hot strip mill. A new simplified finite element method （FEM） was used to analyze the temperature field and thermal crown of roll, and corresponding models were built according to the practical boundary conditions. Transient roll temperature field and thermal crown were simulated by ANSYS FEM software with considering transient thermal contact and complex boundary condition. Temperature and thermal crown variations on roll surface nodes were obtained. The thermal crown results of roll obtained by FEM simulation were in good agreement with the measured data, indicating that simplified FEM models and results were correct.

关键词： temperature field thermal crown FEM roll

Quantitative analysis on the phase margin of ADRC

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Control Theory and Technology 2023年第1期21卷 4-15页

作者： sheng zhong Yi Huang Beijing Aerospace Automatic Control Institute Beijing100854China Key Laboratory of Systems and Control Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing100049China

The paper analyzes and compares the phase margins of four active disturbance rejection control(ADRC)designs,which are based on different common-used extended state observers(ESOs)of various orders,for second-order *** quantitative results indicate that,besides good dynamic response,ADRC can guarantee enough phase *** is also proved that by decreasing the order of ESO,the phase margin can be ***,it is demonstrated that the phase margins of the ADRC-based systems can be almost uninfluenced by the uncertainties of the system ***,the theoretical results are verified by both simulations and experiments on a motion control platform.

关键词： Uncertain system Active disturbance rejection control(ADRC) Extended state observer(ESO) Phase margin Crossover frequency

Ultrasound-responsive Homopolymer Nanoparticles

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Chinese Journal of Polymer Science 2020年第4期38卷 349-356,I0006页

作者： Bo Yang jian-zhong Du Department of Orthopedics Shanghai Tenth People's HospitalTongji University School of MedicineShanghai 200072China Department of Polymeric Materials School of Materials Science and EngineeringKey Laboratory of Advanced Civil Engineering Materials of Ministry of EducationTongji UniversityShanghai201804China

Nonin vasive ultraso und is a more effective strategy for on-demand drug delivery of polymeric nano particles than many other ***,the preparation of ultrasound-responsive homopolymer nanoparticles is still very *** this study,we disclose the regulating factors of ultrasound responsiveness of homopolymer nanoparticles and the disaggregation behavior of homopolymer nanoparticle *** nanoparticles such as vesicles and large compound micelles(LCMs)are self-assembled from poly(methoxyethyl methacrylate)(PMEMA)and poly(amic acid)(PAA),*** ultrasound responsiveness of PAA vesicles at metastable state could be regulated by tuning the self-assembly temperature(7^),and was optimized when Ts is around the glass transition temperature(7g)of ***,the PMEMA LCMs did not respond to ultrasound as they are at stable *** the other hand,poly(2-(2-ethoxyethoxy)ethyl acrylate)(PEEA)could self-assemble into vesicle aggregates or complex micelle aggregates,which were dissociated upon ***,the above findings provide us with a fresh in sight for designing ultrasound-responsive polymeric nanoparticles.

关键词： Ultrasound responsiveness Homopolymers Vesicles Micelles Self-assembly

Certificateless key-insulated signature without random oracles

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第12期10卷 1790-1800页

作者： zhong-mei WAN Xue-jia LAI jian WENG sheng-li LIU Yu LONG Xuan HONG Department of Computer Science and Engineering Shanghai Jiao Tong University Shanghai 200240 China College of Science Hohai University Nanjing 210098 China Department of Computer Science Jinan University Guangzhou 510630 China School of lnformation Systems Singapore Management University Singapore 178902 Singapore

Leakage of the private key has become a serious problem of menacing the cryptosystem security. To reduce the underlying danger induced by private key leakage, Dodis et al.(2003) proposed the first key-insulated signature scheme. To handle issues concerning the private key leakage in certificateless signature schemes, we devise the first certificateless key-insulated signature scheme. Our scheme applies the key-insulated mechanism to certificateless cryptography, one with neither certificate nor key escrow. We incorporate Waters (2005)’s signature scheme, Paterson and Schuldt (2006)’s identity-based signature scheme, and Liu et al.(2007)’s certificateless signature scheme to obtain a certificateless key-insulated signature scheme. Our scheme has two desirable properties. First, its security can be proved under the non-pairing-based generalized bilinear Diffie-Hellman (NGBDH) conjecture, without utilizing the random oracle model; second, it solves the key escrow problem in identity-based key-insulated signatures.

关键词： Key-insulated Key leakage Certificateless Bilinear map

ON THE CONVERGENCE OF WAVEFORM RELAXATION METHODS FOR LINEAR INITIAL VALUE PROBLEMS

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Journal of Computational Mathematics 2004年第5期22卷 681-698页

作者： jian-yuPan zhong-zhiBai LSEC ICMSECAcademyofMathematicsandSystemSciencesChineseAcademyofSciencesBeijing100080China

We study a class of blockwise waveform relaxation methods, and investigate its convergence properties in both asymptotic and monotone senses. In addition, the monotone convergence rates between different pointwise/blockwise waveform relaxation methods resulted from different matrix splittings, and those between the pointwise and blockwise waveform relaxation methods are discussed in depth.

关键词： Asymptotic and monotone convergence Blockwise waveform relaxation method Comparison results