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Three-segment control theory of MgO/Al2O3 ratio based on viscosity experiments and phase diagram analyses at 1500℃

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Journal of Iron and Steel Research International 2020年第6期27卷 624-630页

作者： Xin Jiang Huai-yu Zhang Hai-yan Zheng qiang-jian Gao Feng-man Shen School of Metallurgy Northeastern UniversityShenyang 110819LiaoningChina

In recent years, more and more high Al2O3 iron ores were used in East Asia, especially in China, which increased the Al2O3 content in blast furnace (BF) slag and resulted in poor metallurgical properties of slag. Adding MgO-bearing flux is one of the methods to improve the metallurgical properties of slag with high Al2O3. However, there is lack of theoretical basis for the proper MgO/Al2O3 ratio. Therefore, the properties of slag in SiO2-CaO-MgO-Al2O3 system were investigated based on viscosity experiments and phase diagram analyses at 1500℃, and the proper MgO/Al2O3 ratio was explored according to the Al2O3 content in slag. The experimental results show that: (1) in the case of Al2O3 content less than 14mass%, there is no limitation of the MgO/Al2O3 ratio, and the amount of MgO in slag can be determined according to the hearth tempera-ture and desulfurization;(2) in the case of Al2O3 content between 15 and 17mass%, the proper MgO/Al2O3 ratio should be 0.40-0.50;(3) in the case of Al2O3 content between 18 and 20mass%, the proper MgO/Al2O3 ratio should be 0.45-0.55. Consequently, the three-segment control theory of MgO/Al2O3 for BF slag was built, and the actual BF performances proved the validity and applicability of this theory. The research contents and results can give theoretical guidelines for stable BF operation in a wide range of Al2O3 content of 12-20mass%.

关键词： MgO/Al2O3 ratio Blast furnace slag Viscosity Ironmaking Phase diagram

Thermal Inertia of 330 MW Circulating Fluidized Bed Boiler during Load Change

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Journal of Thermal Science 2023年第5期32卷 1771-1783页

作者： SUN Guorui WU Haowen liu Shangzhong liu Tonghua liu Jixiang YANG Hairui ZHANG man Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Wuhan Yongping Science and Technology Co.Ltd. Wuhan 430000China

The operating principles of Circulating Fluidized Bed(CFB)boilers involve a significant amount of heat accumulation,which forms the thermal inertia of the boiler and hinders the improvement of its variable load response *** study aims to characterize the thermal inertia of CFB boilers by evaluating the change in the boiler's heat accumulation corresponding to the change in unit power *** thermal inertia of a 330MW CFB boiler was determined through the collection of operating data under four different operating conditions of 30%,50%,75%,and 100%*** study proposes to substitute the existing refractory material with a metal grille to reduce the thermal inertia of the *** effect of the metal grille on heat transfer was confirmed through verification on a 440 t/h CFB boiler,and its performance change and thermal inertia reduction were further *** results indicate that over 50%of the total thermal inertia of CFB boilers originates from the refractory *** use of metal grille in place of refractory material improved heat transfer in the furnace,resulting in a decrease of the furnace chamber temperature by 13℃in the 330 MW CFB *** reduction of thermal inertia by 30%-35%will facilitate faster load lifting and lowering of the boiler,fulfilling the requirement for flexible peaking.

关键词： CFB boiler refractory thermal inertia heat accumulation

Highly inhibited transport of dissolved thallium(I) in manganese oxide-coated sand: Chemical condition effects and retention mechanisms

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Journal of Environmental Sciences 2023年第7期129卷 104-114页

作者： Xiaoliu Huangfu Ziqiang liu Hainan Wang qiang He Hongxia liu Caihong liu Key Laboratory of Eco-Environments in Three Gorges Reservoir Region Ministry of EducationCollege of Environment and EcologyChongqing UniversityChongqing 400044China State Key Laboratory of Pollution Control and Resource Reuse School of EnvironmentNanjing UniversityNanjing 210023China

Thallium contamination in water can cause great danger to the *** this study,we synthesized manganese oxide-coated sand(MOCS)and investigated the transport and retention behaviors of Tl(I)in MOCS under different *** methods combined with a two-site nonequilibrium transport model were applied to explore the *** results showed that Tl(I)mobility was strongly inhibited in MOCS media,and the retention capacity calculated from the fitted model was 510.41 mg/g under neutral *** retention process included adsorption and oxidative precipitation by the manganese oxides coated on the sand *** with the same concentration of Mn(II)led to halving Tl(I)retention due to competition for reactive *** Tl(I)retention was observed under alkaline conditions,as increasing pH promoted electronegativity on the media ***,the competitive cation Ca^(2+)significantly weakened Tl(I)retention by occupying adsorption *** findings provide new insights into understanding Tl(I)transport behavior in water-saturated porous media and suggest that manganese oxide-coated sand can be a cost-effective filter media for treating Tl-contaminated water.

关键词： Thallium(I) manganese oxide-coated sand Transport and retention Adsorption Oxidative precipitation

Identifying the sensitive areas in targeted observation for predicting the Kuroshio large meander path in a regional ocean model

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Acta Oceanologica Sinica 2022年第2期41卷 3-14页

作者： Xia liu qiang Wang Mu Mu School of Mathematics Zhengzhou University of AeronauticsZhengzhou 450046China Key Laboratory of Marine Hazards Forecasting of Ministry of Natural Resources Hohai UniversityNanjing 210098China College of Oceanography Hohai UniversityNanjing 210098China Institute of Atmospheric Sciences Fudan UniversityShanghai 200438China

With the Regional Ocean Modeling System(ROMS),this paper investigates the sensitive areas in targeted observation for predicting the Kuroshio large meander(LM)path using the conditional nonlinear optimal perturbation *** identify the sensitive areas,the optimal initial errors(OIEs)featuring the largest nonlinear evolution in the LM prediction are first calculated;the resulting OIEs are localized mainly in the upper 2500 m over the LM upstream region,and their spatial structure has certain similarities with that of the optimal triggering *** on this spatial structure,the sensitive areas are successfully identified,located southeast of Kyushu in the region(29°–32°N,131°–134°E).A series of sensitivity experiments indicate that both the positions and the spatial structure of initial errors have important effects on the LM prediction,verifying the validity of the sensitive ***,the effect of targeted observation in the sensitive areas is evaluated through observing system simulation *** targeted observation is implemented in the identified sensitive areas,the prediction errors are effectively reduced,and the prediction skill of the LM event is improved *** provides scientific guidance for ocean observations related to enhancing the prediction skill of the LM event.

关键词： Kuroshio large meander targeted observation sensitive areas ROMS

Ceramic membrane separation technique for washing nano-sized ceramic powder precursors

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Particuology 2011年第5期9卷 492-496页

作者： qiang Dong Xingqin liu Tianshu Zhang Department of Chemistry ＆ Materials Engineering. Hefei University Hefei 230022 China USTC Lab for Solid State Chemistry and Inorganic Membranes Department of Materials Science ＆ Engineering University of Science ＆ Technology of China Hefei 230026 China School of Materials Science and Engineering The University of New South Wales Sydney NSW2052 Australia

Washing using ceramic micro-filtration membranes was studied in the preparation of nano-sized TiO2 and A1203 powder precursors obtained by wet chemical methods. The key parameters for the washing process, such as operation pressure, cross-flow velocity, and slurry concentration, were examined and optimized. The shape and size of particles influenced the structure of the filter cake, leading to different permeation flux for different systems. The results demonstrated that washing using ceramic membranes is superior to the traditional plate-and-frame filtration and could be considered an advanced technique for ultra-fine powder preparation by wet-chemical method.

关键词： Nano-sized ceramic powder Wet-chemical method Ceramic membrane Washing Filtration

Experimental study on geochemical characteristic of methane hydrate formed in porous media

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Journal of Natural Gas Chemistry 2009年第2期18卷 217-221页

作者： qiang Chen Changling liu Yuguang Ye Qingdao Institute of Marine Geology the Ministry of Land and Resources Qingdao 266071 Shandong China The key Laboratory of Marine Hydrocarbon Resources and Environment Resources the Ministry of Land and Resources Qingdao 266071 Shangdong China

The natural occurrence of methane hydrates in marine sediments has been intensively studied over the past decades, and geochemical charac-teristic of hydrate is one of the most attractive research fields. In this paper, we discussed the geochemical anomaly during hydrate formation in porous media. By doing so, we also investigated the temperature influence on hydrate formation under isobaric condition. It turns out that sub-cooling is an important factor to dominate hydrate formation. Larger subcooling provides more powerful driving force for hydrate formation. During the geochemical anomaly research, six kinds of ions and the total dissolved salt （TDS） were measured before and after the experiment in different porous media. The result is that all kinds of ionic concentration increased after hydrate formation which can be defined as salting out effect mainly affected by gas consumption. But the variation ratio of different ions is not equal. Ca^2＋ seems to be the most significantly influenced one, and its variation ratio is up to 80%. Finally, we theoretically made a model to calculate the TDS variation, the result is in good accordance with measured one, especially when gas consumption is large.

关键词： hydrate formation porous media subcooling salting out effect geochemical anomaly

Multicolored Bipartite Ramsey Numbers of Large Cycles

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 347-357页

作者： Shao-qiang liu Yue-jian PENG College of Mathematics and Statistics Hanshan Normal UniversityChaozhou 521041China School of Mathematics Hunan UniversityChangsha 410082China

For an integer r≥2 and bipartite graphs Hi,where 1≤i≤r,the bipartite Ramsey number br(H1,H2,…,Hr)is the minimum integer N such that any r-edge coloring of the complete bipartite graph KN;N contains a monochromatic subgraph isomorphic to Hi in color i for some 1≤i≤*** show that if r≥3;α1,α2>0,αj+2≥[(j+2)!-1]Σi=1^(j+1)α1 for j=1,2…r-2,then br(C2[α1n],C2[α2n],…,C2[αrn]=(Σ=j=1^(r)a j+o(1))n.

关键词： ramsey number bipartite ramsey number regularity lemma

Efficiently simulating the work distribution of multiple identical bosons with boson sampling

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Frontiers of physics 2024年第3期19卷 197-206页

作者： Wen-qiang liu Zhang-qi Yin Center for Quantum Technology Research and Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurements(MOE) School of PhysicsBeijing Institute of TechnologyBeijing 100081China

Boson sampling has been theoretically proposed and experimentally demonstrated to show quantum computational ***,it still lacks the deep understanding of the practical applications of boson *** we propose that boson sampling can be used to efficiently simulate the work distribution of multiple identical *** link the work distribution to boson sampling and numerically calculate the transition amplitude matrix between the single-boson eigenstates in a one-dimensional quantum piston system,and then map the matrix to a linear optical network of boson *** work distribution can be efficiently simulated by the output probabilities of boson sampling using the method of the grouped probability *** scheme requires at most a polynomial number of the samples and the optical *** work opens up a new path towards the calculation of complex quantum work distribution using only photons and linear optics.

关键词： quantum simulation quantum work distribution boson sampling linear optic

Automatic"Ground Truth"Annotation and Industrial Workpiece Dataset Generation for Deep Learning

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International Journal of Automation and computing 2020年第4期17卷 539-550页

作者： Fu-qiang liu Zong-Yi Wang College of Automation Harbin Engineering UniversityNo.145 Nantong RoadNangang DistrictHarbin 150001China

In industry,it is becoming common to detect and recognize industrial workpieces using deep learning *** this field,the lack of datasets is a big problem,and collecting and annotating datasets in this field is very labor *** researchers need to perform dataset annotation if a dataset is generated by *** is also one of the restrictive factors that the current method based on deep learning cannot expand *** present,there are very few workpiece datasets for industrial fields,and the existing datasets are generated from ideal workpiece computer aided design(CAD)models,for which few actual workpiece images were collected and *** propose an automatic industrial workpiece dataset generation method and an automatic ground truth annotation *** in our methods are three algorithms that we proposed:a point cloud based spatial plane segmentation algorithm to segment the workpieces in the real scene and to obtain the annotation information of the workpieces in the images captured in the real scene;a random multiple workpiece generation algorithm to generate abundant composition datasets with random rotation workpiece angles and positions;and a tangent vector based contour tracking and completion algorithm to get improved contour *** our procedures,annotation information can be obtained using the algorithms proposed in this *** completion of the annotation process,a json format file is *** R-CNN(Faster R-convolutional neural network),SSD(single shot multibox detector)and YOLO(you only look once:unified,real-time object detection)are trained using the datasets proposed in this *** experimental results show the effectiveness and integrity of this dataset generation and annotation method.

关键词： Deep learning dataset generation automatic annotation neural networks industrial workpiece dataset