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Products of carbothermic reduction of Fe-Cr-O and Fe-Cr-Ni-O systems 被引量:1
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作者 张延玲 刘洋 魏文洁 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期1210-1219,共10页
The reduction behaviors and characteristics of products of the Fe-Cr-O system (FeCr2O4 and Fe2O3+Cr2O3) and Fe-Cr-Ni-O system (Fe2O3+Cr2O3+NiO) under various conditions were studied. The results show that more ... The reduction behaviors and characteristics of products of the Fe-Cr-O system (FeCr2O4 and Fe2O3+Cr2O3) and Fe-Cr-Ni-O system (Fe2O3+Cr2O3+NiO) under various conditions were studied. The results show that more Fe-Cr or Fe-Cr-Ni solution and less residual carbon content were obtained at higher temperatures and lower initial molar ratio of C to O (nC:nO). The degree of reduction was highly dependent on both time and temperature, and the residual carbon content greatly increased with increasing nC:nO at each temperature. The products generated during the carbothermic reduction of the Fe-Cr-O system were examined using X-ray diffraction (XRD). A scanning electron microscope (SEM) coupled with energy dispersive spectrometer was used to observe the microstructure and the distribution of elements in the various phases of the final reduction products of the Fe-Cr-O and Fe-Cr-Ni-O. 展开更多
关键词 Fe-Cr-O system Fe-Cr-Ni-O system reduction product element distribution residual carbon content
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China’s Potential of Grain Production Due to Changes in Agricultural Land Utilization in Recent Years 被引量:19
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作者 XIN Liangjie LI Xiubin +1 位作者 ZHU Huiyi TAN Minghong 《Chinese Geographical Science》 SCIE CSCD 2009年第2期97-103,共7页
The changes in utilization of agricultural land have gradually grown into one of the major factors impacting grain output in China. This study explores the various components of agricultural production in China from t... The changes in utilization of agricultural land have gradually grown into one of the major factors impacting grain output in China. This study explores the various components of agricultural production in China from the land utilization perspective, involving changes in grain production per unit area, multi-cropping index, and adjustment of agricultural structure. Compared with the record values, different research methodologies are used to analyze the po- tential of above three components. The results indicate that grain production potential of 65.68×109kg was unexploited in 2006, in which 45.8×109kg came from the restructuring in agriculture. So we can infer that the reduction of grain production in China could be primarily attributed to agricultural restructuring in recent years. So the productive poten- tial can be fully restored by increasing agricultural investment, or recovering agricultural structure in favorable condi- tions. So we can say that China’s current condition of food security is good. 展开更多
关键词 grain production potential of grain production agricultural land utilization changes multi-cropping index reduction of grain product food security
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Near-infrared H_(2)O_(2)production via dual pathways of O_(2)reduction and H_(2)O oxidation
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作者 Yingpu Bi 《Science China Chemistry》 SCIE EI CAS CSCD 2023年第5期1239-1240,共2页
Hydrogen peroxide(H_(2)O_(2))is a chemical that is widely of interest in both environmental and energy fields.On the one hand,as a clean oxidant,H_(2)O_(2)has been commonly used in the field of bleaching,disinfection,... Hydrogen peroxide(H_(2)O_(2))is a chemical that is widely of interest in both environmental and energy fields.On the one hand,as a clean oxidant,H_(2)O_(2)has been commonly used in the field of bleaching,disinfection,and advanced oxidation processes.On the other hand,H_(2)O_(2)has also been explored as a liquid fuel alternative to H_(2)or fossil fuels in fuel cells due to its high energy density.However,the current industrial production of H_(2)O_(2)relies on the anthraquinone(AO)method that involves palladium-catalyzed hydrogenation-oxidation steps. 展开更多
关键词 Near-infrared H_(2)O_(2)production via dual pathways of O_(2)reduction and H_(2)O oxidation
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DYNAMIC MODELING FOR AIRSHIP EQUIPPED WITH BALLONETS AND BALLAST 被引量:9
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作者 CAI Zi-li(蔡自立) Qu Wei-dong(屈卫东) XI Yu-geng(席裕庚) 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI 2005年第8期1072-1082,共11页
Total dynamics of an airship is modeled. The body of an airship is taken as a submerged rigid body with neutral buoyancy, i. e. , buoyancy with value equal to that of gravity, and the coupled dynamics between the body... Total dynamics of an airship is modeled. The body of an airship is taken as a submerged rigid body with neutral buoyancy, i. e. , buoyancy with value equal to that of gravity, and the coupled dynamics between the body with ballonets and ballast is considered. The total dynamics of the airship is firstly derived by Newton-Euler laws and Kirchhoff' s equations. Furthermore, by using Hamiltonian and Lagrangian semidirect product reduction theories, the dynamics is formulated as a Lie-Poisson system, or also an Euler-Poincare system. These two formulations can be exploited for the control design using energy-based methods for Hamiltonian or Lagrangian system. 展开更多
关键词 AIRSHIP dynamical modeling Kirchhoff' s equation semi-direct product reduction
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The Role of Forced Oscillators of Coupled Circuits in Radiation Physics: New Linear Accelerator Design Improving Tomo-Scanning Technology (Radiotherapy and CT), Heisenberg-Euler Scatter, and Extension to Bremsstrahlung with GeV Electrons
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作者 W. Ulmer 《Journal of Applied Mathematics and Physics》 2021年第4期707-735,共29页
The quantization of circuits has received to be rather attractive in domains of solid state—molecular—and biophysics, since the quanta referred to as Q-bits play a significant role in the design of the quantum compu... The quantization of circuits has received to be rather attractive in domains of solid state—molecular—and biophysics, since the quanta referred to as Q-bits play a significant role in the design of the quantum computer and entangled structures. Quantized circuits cannot be applied without modifications, since the energy differences are not equidistant and the polarization of the excited states has to be accounted for having particular importance for the creation of virtual states. Applications of the presented theory are scanning methods in radiotherapy without multi-leaf collimators, which may be realized in tomo-scanning radiotherapy and in the keV domain, which provides a new design of CT. The problem of lateral scatter in the target and energy storage by heat production is significantly reduced by a multilayer system with focusing the impinging electrons at the walls and by a magnetic field. The verification of the Heisenberg-Euler scatter of crossing beams of 9 MV is a central problem of photon physics and can be solved by the new bremsstrahlung technique. A comparison with GEANT 4 Monte-Carlo data indicates that the presented method also works in the GeV domain, and a multi-target can improve the bremsstrahlung yield. GEANT 4 provides the spatial distribution, whereas the virtual oscillator states only show the created energy spectrum. In every case, the exploitation yield can be drastically improved by the superiority of the focused multitarget system compared to a single standard target, and the door to new technologies is opened. 展开更多
关键词 Harmonic Oscillators in Charge Space Polarization of Energy Levels Bremsstrahlung Creation Focusing of Multitargets reduction of Scatter and Heat production
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Effects of operating conditions on iron(hydr)oxides evolution and ciprofloxacin degradation in potassium ferrate-ozone stepwise oxidation system
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作者 Xiaochen Li Yifan Wang +4 位作者 Ning Wang Mei Li Maomao Bai Jingtao Xu Hongbo Wang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2024年第1期367-378,共12页
In this study,a stepwise oxidation system of potassium ferrate(K_(2)FeO_(4))combined with ozone(O+3)was used to degrade ciprofloxacin(CIP).The effects of pH and pre-oxidation time of K_(2)FeO_(4) on the evolution of K... In this study,a stepwise oxidation system of potassium ferrate(K_(2)FeO_(4))combined with ozone(O+3)was used to degrade ciprofloxacin(CIP).The effects of pH and pre-oxidation time of K_(2)FeO_(4) on the evolution of K_(2)FeO_(4) reduction products(iron(hydr)oxides)and CIP degradation were investigated.It was found that in addition to its own oxidation capacity,K_(2)FeO_(4) can also influence the treatment effect of CIP by changing the catalyst content.The presence of iron(hydr)oxides effectively enhanced the mineralization rate of CIP by catalyzing ozonation.The pH value can influence the content and types of the components with catalytic ozonation effect in iron(hydr)oxides.The K_(2)FeO_(4) pre-oxidation stage can produce more iron(hydr)oxides with catalytic components for subsequent ozonation,but the evolution of iron(hydr)oxides components was influenced by O_(3) treatment.It can also avoid the waste of oxidation capacity owing to the oxidation of iron(hydr)oxides by O_(3) and free radicals.The intermediate degradation products were identified by Fourier transform ion cyclotron resonance mass spectrometry(FT-ICR-MS).Besides,the degradation pathways were proposed.Among the degradation products of CIP,the product with broken quinolone ring structure only appeared in the stepwise oxidation system. 展开更多
关键词 Potassium ferrate reduction products Catalytic ozonation CIPROFLOXACIN Potassium ferrate pre-oxidation time
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Recovery of boron from high-boron iron concentrate using reduction roasting and magnetic separation 被引量:4
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作者 Jian-wen Yu Yue-xin Han +1 位作者 Peng Gao Yan-jun Li 《Journal of Iron and Steel Research International》 SCIE EI CAS CSCD 2017年第2期131-137,共7页
The comprehensive utilization of abundant high-boron iron concentrate is of particular significance to Chi- na, and the high-boron iron concentrate has not yet been utilized as a source for boron at an industrial scal... The comprehensive utilization of abundant high-boron iron concentrate is of particular significance to Chi- na, and the high-boron iron concentrate has not yet been utilized as a source for boron at an industrial scale due to its complex mineralogy and fine mineral dissemination. An innovative method was proposed for recovery of boron and iron from high-boron iron concentrate by reduction roasting and magnetic sepa- ration. The effects of reduction temperature and roasting time were investigated and their optimum condi- tions were determined. The mineralogical changes during roasting were characterized by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The results showed that the pyrrhotite (FeS) contained in the high-boron iron concentrate and the new-formed FeS-Fe solid solution softened or melted at high temperatures owing to their low melting points, and then decreased the metallic iron ratio and accelerated the growth of metallic iron particles. Meanwhile, the magnetite and szaibelyite were converted into metal- lic iron and suanite, respectively. Consequently, boron was readily enriched into the non-magnetic product and the metallic iron was aggregated to the magnetic concentrate by magnetic separation. Boron recovery of 88.6% with corresponding B2O3 content of 14.5% and iron recovery of 95.1% with an iron grade of 92.7% were achieved when high-boron iron concentrate was reduced at 1 125℃ for 150 min. Besides, the boron reactivity of the boron-rich non-magnetic product was up to 80.8%. 展开更多
关键词 High-boron ironconcentrateCarbothermic reduction Magnetic separation Metallic iron Boron-rich non magnetic product
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0D/3D direct Z-scheme heterojunctions hybridizing by MoS2 quantum dots and honeycomb conjugated triazine polymers (CTPs) for enhanced photocatalytic performance
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作者 Shuqi Li Weishun Lai +6 位作者 Xinming Jiang Yashuang Wang Xinyi Cai Da Wang Shuang Song Min Liu Tao Zeng 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2023年第2期602-616,共15页
Herein,a novel direct Z-scheme photocatalyst was accomplished by hybridization of 0D MoS2 quantum dots(MSQDs)and 3D honeycomb-like conjugated triazine polymers(CTP)(namely,CTP-MSQD).The unique 0D/3D hierarchical struc... Herein,a novel direct Z-scheme photocatalyst was accomplished by hybridization of 0D MoS2 quantum dots(MSQDs)and 3D honeycomb-like conjugated triazine polymers(CTP)(namely,CTP-MSQD).The unique 0D/3D hierarchical structure significantly enhanced the exposure of active sites and light harvesting property,while the formed p-n junction enabled the direct strong interface coupling without the necessity of any mediators.The optimized CTP-MSQD3 exhibited continuously increased visible-light-driven photocatalytic activity and strong durability both in Cr(VI)reduction and H2 evolution,featured a rate of 0.069 min^(-1) and 1070μmol/(hr•g),respectively,which were 8 times than those of pure 3D-CTP(0.009 min^(−1) and 129μmol/(hr•g)).We believe that this work provides a promising photocatalyst system that combines a 0D/3D hierarchical structure and a Z-scheme charge flow for efficient and stable photocatalytic conversion. 展开更多
关键词 0D/3D structure Conjugated triazine polymers MoS2 quantum dots Direct Z-scheme mechanism Cr(VI)reduction and H2 production
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New method for high performance multiply-accumulator design 被引量:1
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作者 Bing-jie XIA Peng LIU Qing-dong YAO 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2009年第7期1067-1074,共8页
This study presents a new method of 4-pipelined high-performance split multiply-accumulator (MAC) architecture, which is capable of supporting multiple precisions developed for media processors. To speed up the design... This study presents a new method of 4-pipelined high-performance split multiply-accumulator (MAC) architecture, which is capable of supporting multiple precisions developed for media processors. To speed up the design further, a novel partial product compression circuit based on interleaved adders and a modified hybrid partial product reduction tree (PPRT) scheme are proposed. The MAC can perform 1-way 32-bit, 4-way 16-bit signed/unsigned multiply or multiply-accumulate operations and 2-way parallel multiply add (PMADD) operations at a high frequency of 1.25 GHz under worst-case conditions and 1.67 GHz under typical-case conditions, respectively. Compared with the MAC in 32-bit microprocessor without interlocked piped stages (MIPS), the proposed design shows a great advantage in speed. Moreover, an improvement of up to 32% in throughput is achieved. The MAC design has been fabricated with Taiwan Semiconductor Manufacturing Company (TSMC) 90-nm CMOS standard cell technology and has passed a functional test. 展开更多
关键词 Multiply-accumulator (MAC) PIPELINE COMPRESSOR Partial product reduction tree (PPRT) Split structure
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An Elastic Architecture Adaptable to Various Application Scenarios
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作者 伍岳 陈云霁 +2 位作者 陈天石 郭崎 张磊 《Journal of Computer Science & Technology》 SCIE EI CSCD 2014年第2期227-238,共12页
The quantity of computer applications is increasing dramatically as the computer industry prospers. Meanwhile, even for one application, it has different requirements of performance and power in different scenarios. A... The quantity of computer applications is increasing dramatically as the computer industry prospers. Meanwhile, even for one application, it has different requirements of performance and power in different scenarios. Although various processors with different architectures emerge to fit for the various applications in different scenarios, it is impossible to design a dedicated processor to meet all the requirements. Furthermore, dealing with uncertain processors significantly aggravates the burden of programmers and system integrators to achieve specific performance/power. In this paper, we propose elastic architecture (EA) to provide a uniform computing platform with high elasticity, i.e., the ratio of worst-case to best-case performance/power/performance-power trade-off, which can meet different requirements for different applications. It is achieved by dynamically adjusting architecture parameters (instruction set, branch predictor, data path, memory hierarchy, concurrency, status^zcontrol, and so on) on demand. The elasticity of our prototype implementation of EA, as Sim-EA, ranges from 3.31 to 14.34, with 5.41 in arithmetic average, for SPEC CPU2000 benchmark suites, which provides great flexibility to fulfill the different performance and power requirements in different scenarios. Moreover, Sim-EA can reduce the EDP (energy-delay product) for 31.14% in arithmetic average compared with a baseline fixed architecture. Besides, some subsequent experiments indicate a negative correlation between application intervals' lengths and their elasticities. 展开更多
关键词 architecture design CONFIGURABLE ELASTICITY energy-delay product reduction
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