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Rules of Assimilation of Single ore and Mixed ores

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Journal of Iron and Steel Research International 2013年第9期20卷 8-15页

作者： SU Bu-xin ZHANG Jian-liang WANG da SHAo Jiu-gang REN Shan WANG Guang-wei State Key Laboratory of Advanced Metallurgy University of Science and Technology Beijing

Assimilation behaviors of 7 kinds of iron ores from Australia, Brazil, India, South Africa and China were evalua-ted and analyzed. on the basis of that, four ore blending principles were proposed, and seven groups of iron ore pow-der blending schemes were designed. The ores of different types or from different places are shown apparently differ-ent in assimilation. The assimilation of hematite in Australia, Brazil and India is relatively high, but the assimilation o{ magnetite in South Africa and China and specularite in China is relatively low. The assimilation of the ores has negative correlation with Mgo content and binary basicity, while the assimilation of the ores has positive correlation with porosity, Sio2 and Al2o3 contents, and crystal water. The iron ores with smaller crystal size and microstruc- ture looseness have relatively higher assimilation. Assimilation of mixed ores has relationship of linear, arch and ＂S＂ types to the ratio of single iron ore powder. When the charge ratio of ore is less than 25%, it possesses additivity, providing theoretical basis for optimization of ore matching.

关键词： single ore mixed ore sintering assimilation

The potential of domestic production and imports of oil and gas in China:an energy return on investment perspective

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Petroleum Science 2016年第4期13卷 788-804页

作者： Zhao-Yang Kong Xiu-Cheng Dong Qian Shao Xin Wan da-Lin Tang Gui-Xian Liu School of Business Administration China University of Petroleum(Beijing)Beijing 102249China School of Business Tianjin University of Finance and EconomicsTianjin 300222China Tangshan Iron and Steel Group Co. LtdTangshan 261000China China Petroleum Enterprise Association Beijing 100724China

Concerns about China’s energy security have escalated because of the country’s high dependency on oil and gas imports, so it is necessary to calculate the availability of domestic oil and gas resources and China’s ability to obtain foreign energy through trade. In this work,the calculation was done by using the energy return on investment（ERoI） method. The results showed that the ERoIstnd（i.e., standard ERoI） of China’s oil and gas extraction decreased from approximately 17.3：1 in 1986 to 8.4：1 in 2003, but it increased to 12.2：1 in 2013. From a company-level perspective, the ERoIstnddiffered for different companies and was in the range of（8–12）：1. The ERoI2,d（ERoI considering energy outputs after processed and direct energy inputs） for different companies was in the range of（3–7）：1. The ERoI of imported oil（ERoIIo）declined from 14.8：1 in 1998 to approximately 4.8：1 in 2014, and the ERoI of imported natural gas（ERoIING）declined from 16.7：1 in 2009 to 8.6：1 in 2014. In 2015, the ERoIIo and ERoIING showed a slight increase due to decreasing import prices. In general, this paper suggests that from a net energy perspective, it has become more difficult for China to obtain oil and gas from both domestic production and imports. China is experiencing an ERoI decline, which demonstrates the risk in the use of unsustainable fossil resources.

关键词： ERoI oil and gas extraction Imported oil Imported natural gas China

Diffusive Lorenz dynamics: Coherent structures and spatiotemporal chaos

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Communications in Nonlinear Science and Numerical Simulation 2000年第2期5卷 49-57页

作者： Yuehong QiaN Hudong CHEN and da-Hsuan FENG (Exa Corporation, 450 Bedford Street, Lexington, MA 02420, USA email: qian@***, hudong@exa. Com Department of Physics, Drexel University, Philadelphia, PA 19104, USA email: da.hsuan.feng@***) Exa Corporation 450 Bedford Street Lexington MA 02420 USA Department of Physics Drexel University Philadelphia PA 19104 USA

In this paper, we are interested in collective behaviors of many interacting Lorenz strange attractors. With an intermediate chion coupling between the attractors,a new remarkable synchronization of well orgtried structuxes merges as a result of two competing mechanisms: temporal chaos and spatial chsive stabilization. A window of the coupling parazneter for coherent structures is found numerically. Different from all exist ing scenarios of routes to chaos (period doubling, intermittency and strange attractors), an algorithmetic increase of wavenumbers before an abrupt change to chaos (compared to the periodic doubling geometrical) is unexpectedly discovered. Metastable states are also ob served in simulations.

关键词： synchronizied chaos coherent structures intermittency reaction-diffusion

GeneticKNN:a weighted KNN approach supported by genetic algorithm for photometric redshift estimation of quasars

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Research in Astronomy and Astrophysics 2021年第1期21卷 165-177页

作者： Bo Han Li-Na Qiao Jing-Lin Chen Xian-da Zhang Yan-Xia Zhang Yong-Heng Zhao School of Computer Science Wuhan UniversityWuhan 430072China Institute of Electronics Chinese Academy of SciencesBeijing 100190China CAS Key Laboratory of optical Astronomy National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China

We combine K-nearest neighbors(KNN)with a genetic algorithm(GA)for photometric redshift estimation of quasars,short for GeneticKNN,which is a weighted KNN approach supported by a *** approach has two improvements compared to KNN:one is the feature weighted by GA;the other is that the predicted redshift is not the redshift average of K neighbors but the weighted average of median and mean of redshifts for K neighbors,i.e.p×zmedian+(1-p)×*** on the SDSS and SDSS-WISE quasar samples,we explore the performance of GeneticKNN for photometric redshift estimation,comparing with the other six traditional machine learning methods,*** least absolute shrinkage and selection operator(LASSo),support vector regression(SVR),multi-layer perceptrons(MLP),XGBoost,KNN and random *** and random forest show their *** the easy implementation of KNN,we make improvement on KNN as GeneticKNN and apply GeneticKNN on photometric redshift estimation of *** the performance of GeneticKNN is better than that of LASSo,SVR,MLP,XGBoost,KNN and random forest for all *** the accuracy is better with the additional WISE magnitudes for the same method.

关键词： astronomical databases:catalogs (galaxies:)quasars:general methods:statistical techniques:miscellaneous

Precipitation Strengthening by Nanometer-sized Carbides in Hot-rolled Ferritic Steels

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Journal of Iron and Steel Research International 2014年第12期21卷 1140-1146页

作者： Xiao-pei WANG Ai-min ZHAo Zheng-zhi ZHAo Yao HUANG Zhi-da GENG Yang YU Sheet Metal Research Institute Shougang Research Institute of Technology Metallurgical Engineering Research Institute University of Science and Technology Beijing

The mechanical properties of the hot-rolled plates of Ti steel and Ti-Mo steel after isothermal transformation in a temperature range of 600 700 ℃ for 60 min have been tested, and the microstructures of the matrix and the characteristics of precipitated nanometer-sized carbides have also been examined by scanning electron microscopy and transmission electron microscopy. The precipitation regularity of nanometer-sized carbides has been studied by thermodynamic method and the contributions of corresponding strengthening mechanisms to the total yield strength have been calculated. The tensile strength of hot-rolled Ti-Mo ferritie steel can achieve 780 MPa with an elongation of 20.0% after being isothermally treated at 600 ℃ for 60 rain, and the tensile strength of Ti steel is 605 MPa with an elongation of 22.7%, according to the results of tensile tests. The critical nucleation size of （Ti,Mo）C is smaller than that of TiC at a given isothermal temperature, but the nucleation rate of （Ti, Mo）C is larger than that of TiC. The grainrefinement strengthening and precipitation strengthening contribute the main amount of the total yield strength. The major increase in yield strength with the decrease of isothermal temperature results from the contribution of precipi tation strengthening. The contribution of precipitation strengthening to the yield strength of the steels has been esti mated. The ferrite phase can be strengthened by about 400 MPa through precipitation strengthening in Ti-Mo steel isothermally treated at 600 ℃ for 60 rain, which is about 200 MPa higher than that of Ti steel under the same conditions.

关键词： ferritie steel nanometer sized carbide thermodynamic method precipitation strengthening

Alkylation　of　Benzene　with　Propene　over　Hβ　Zeolite──The　Effect　of　Reaction　Conditions　on　the　Distribution　of　Products

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Chemical Research in Chinese Universities 1995年第1期11卷 39-44页

作者： MA Jun SHEN Jian-ping SUN Tie and JiaNG da-zhen(Department of Chernistry , Jilin University , Changchun , 130023 ) JILIN UNIV DEPT CHEMCHANGCHUN 130023PEOPLES R CHINA

he effects of reaction temperature , flow rate of carrier gas , space velocity andbenzene to propene ratio on the alkylation of benzene with propene over Hβ zeolitewere investigated. At lower flow rate of carrier gas and space velocity, higher ben-zene to propene ratio the formation of cumene is favoured due to the difference be-tween rates of reactions of the alkylation of benzene (or cumene) with propene andthe alkyltranslation of diisopropylbenzene with benzene. The propylbenzene is pro-duced directly by the alkylation of benzene with propene.

关键词： Benzene Propene Alkylation Hβ zeolite

Dynamic responses of K-type and inverted-K-type jacket support structures for offshore wind-turbines

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Journal of Central South University 2017年第4期24卷 947-956页

作者： Liao Ying-di GUo Meng-yuan WANG Na HoU Li-jun CHEN da Key Laboratory of Coastal Disaster and Defence Ministry of Education (Hohai University) Nanjing 210098 China College of Harbor Coastal and Offshore Engineering Hohai University Nanjing 210098 China

The jacket structure has become more popular as the offshore wind-turbine support structure. K-type and inverted-K-type jacket support structures have superior potential due to their fewer joints and lower cost of manufacture and installation. A numerical study was presented on the dynamic responses of K-type and inverted-K-type jacket support structures subjected to different kinds of dynamic load. The results show that the inverted-K-type jacket structure has higher natural frequencies than the K-type. The wave force spectrum response shows that the maximum displacement of the K-type jacket structure is larger than that of the inverted-K-type. The time-history responses under wind and wave-current load indicate that the inverted-K-type jacket structure shows smaller displacement and stress compared with the K-type, and presents different stress concentration phenomena. The dynamic responses reveal that the inverted-K-type of jacket support structure has greater stiffness and superior mechanical properties, and thus is more applicable in the offshore area with relatively deep water.

关键词： jacket support structure K-type inverted-K-type foundation dynamic responses

Latent dimensions between water use and socio-economic development: A global exploratory statistical analysis

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Regional Sustainability 2022年第3期3卷 269-280页

作者： Edson Elídio BALATA Hugo PINTo Manuela Moreira da SILVA Institute of Engineering Universidade do AlgarveFaro8005-139Portugal Centre for Social Studies University of CoimbraCoimbra3000-995Portugal Faculty of Economics University of AlgarveFaro8005-139Portugal Centre for Marine and Environmental Research(CIMA) University of AlgarveFaro8005-139Portugal Centre of Engineering and Product Development(CEiia) Matosinhos4450-017Portugal

Water use and socio-economic development are interconnected in complex *** are not easy to identify but it is evident that a nexus between water use and socio-economic development does *** the diversity of national situations relating to these interrelated phenomena,its study should be considered from a global *** article critically reviews the literature and information from official sources on the relevance of water use and circular economy in order to create a global picture,linking water with socio-economic *** from 195 countries were analyzed statistically.A factor analysis defined five essential latent dimensions on the nexus between water use and socio-economic development:development and basic services,population and resources,economic volume,health and well-being,and population *** on the identified factors,countries were classified into six groups:Global South in difficulty,global semi-periphery,advanced economy,Middle East and other Global South developing economy,global weight,and small highly developed *** clustering results clarify connections between water use conditions and socioeconomic *** the variety of national profiles is helpful to reveal the magnitude and urgency of dealing with the nexus between water use and socio-economic development for many countries.

关键词： Water reuse Circular economy Water management Urban water cycle Socio-economic sustainable development Country clusters Factor analysis

Climate and land-use interactively shape butterfly diversity in tropical rainforest and savanna ecosystems of southwestern China

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Insect Science 2021年第4期28卷 1109-1120页

作者： Bai-Ge Miao Yan-Qiong Peng da-Rong Yang Yasuhiro Kubota Evan P.Economo Cong Liu CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglaYunnanChina Plant Ecology Core Botanical GardensChinese Academy of SciencesMenglaYunnanChina Faculty of Science University of the RyukyusNishiharaOkinawaJapan Biodiversity and Biocomplexity Unit Okinawa Institute of Science and Technology Graduate UniversityOnna-sonOkinawaJapan Department of organismic and Evolutionary Biology Museum of Comparative ZoologyHarvard UniversityCambridgeMAUnited States

Human-induced habitat conversion and degradation,along with accelerating climatic change,have resulted in considerable global biodiversity ***,how local ecological assemblages respond to the interplay between climate and land-use change remains poorly ***,we examined the effects of climate and land-use interactions on butterfly diversity in different ecosystems of southwestern ***,we investigated variation in the alpha and beta diversities of butterflies in different landscapes along human-modified and climate *** found that increasing land-use intensity not only caused a dramatic decrease in butterfly alpha diversity but also significantly simplified butterfly species composition in tropical rainforest and savanna *** findings suggest that habitat modification by agricultural activities increases the importance of deterministic processes and leads to biotic *** land-use intensity model best explained species richness variation in the tropical rainforest,whereas the climate and land-use intensity interaction model best explained species richness variation in the *** results indicate that climate modulates the effects of land-use intensity on butterfly alpha diversity in the savanna *** also found that the response of species composition to climate varied between sites:specifically,species composition was strongly correlated with climatic distance in the tropical rainforest but not in the *** together,our long-term butterfly monitoring data reveal that interactions between human-modified habitat change and climate change have shaped butterfly diversity in tropical rainforest and *** findings also have important implications for biodiversity conservation under the current era of rapid human-induced habitat loss and climate change.

关键词： butterfly diversity climate change conservation habitat conversion savanna tropical rainforest