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基于炉缸渣铁滞留量的高炉炉缸活性研究
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作者 刘彦祥 郭子昱 +4 位作者 焦克新 张建良 徐益军 丁望 杨耀明 《炼铁》 CAS 北大核心 2024年第2期49-55,共7页
针对国内外对炉缸活性表征不明晰的问题,建立以炉缸渣铁滞留量表征炉缸活性的模型,定量分析高炉操作参数对炉缸活性的作用比重,并提出提高炉缸活性的操作手段。结果表明:①渣铁焦物性对渣铁滞留率的影响顺序为:铁水温度>CSR>焦炭... 针对国内外对炉缸活性表征不明晰的问题,建立以炉缸渣铁滞留量表征炉缸活性的模型,定量分析高炉操作参数对炉缸活性的作用比重,并提出提高炉缸活性的操作手段。结果表明:①渣铁焦物性对渣铁滞留率的影响顺序为:铁水温度>CSR>焦炭粒度>CRI>炉渣碱度>镁铝比;②去除滞留率对滞留量的影响,高炉操作参数对渣铁滞留量的影响顺序为:风量>铁口深度>风温>风压>喷煤量>氧气量;③高炉生产中,可采用原燃料粒级及性能管控技术、高风速大动能操作技术、渣铁流动控制技术、渣铁排放管控技术高效调控炉缸活跃状态。 展开更多
关键词 高炉 炉缸 炉缸活性 渣铁滞留率 渣铁滞留量 操作参数
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Recent Progress in Reinforcement Learning and Adaptive Dynamic Programming for Advanced Control Applications 被引量:1
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作者 ding wang Ning Gao +2 位作者 Derong Liu Jinna Li Frank L.Lewis 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2024年第1期18-36,共19页
Reinforcement learning(RL) has roots in dynamic programming and it is called adaptive/approximate dynamic programming(ADP) within the control community. This paper reviews recent developments in ADP along with RL and ... Reinforcement learning(RL) has roots in dynamic programming and it is called adaptive/approximate dynamic programming(ADP) within the control community. This paper reviews recent developments in ADP along with RL and its applications to various advanced control fields. First, the background of the development of ADP is described, emphasizing the significance of regulation and tracking control problems. Some effective offline and online algorithms for ADP/adaptive critic control are displayed, where the main results towards discrete-time systems and continuous-time systems are surveyed, respectively.Then, the research progress on adaptive critic control based on the event-triggered framework and under uncertain environment is discussed, respectively, where event-based design, robust stabilization, and game design are reviewed. Moreover, the extensions of ADP for addressing control problems under complex environment attract enormous attention. The ADP architecture is revisited under the perspective of data-driven and RL frameworks,showing how they promote ADP formulation significantly.Finally, several typical control applications with respect to RL and ADP are summarized, particularly in the fields of wastewater treatment processes and power systems, followed by some general prospects for future research. Overall, the comprehensive survey on ADP and RL for advanced control applications has d emonstrated its remarkable potential within the artificial intelligence era. In addition, it also plays a vital role in promoting environmental protection and industrial intelligence. 展开更多
关键词 Adaptive dynamic programming(ADP) advanced control complex environment data-driven control event-triggered design intelligent control neural networks nonlinear systems optimal control reinforcement learning(RL)
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Residual alkali-evoked cross-linked polymer layer for anti-air-sensitivity LiNi_(0.89)Co_(0.06)Mn_(0.05)O_(2)cathode
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作者 Chao Zhao Xuebao Li +7 位作者 Yun Zhao Jingjing He Yuanpeng Cao Wei Luo ding wang Jianguo Duan Xianshu wang Baohua Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第5期450-458,共9页
High-energy density lithium-ion batteries(LIBs)with layered high-nickel oxide cathodes(LiNi_(x)Co_(y)Mn_(1-x-y)O_(2),x≥0.8)show great promise in consumer electronics and vehicular applications.However,LiNi_(x)Co_(y)M... High-energy density lithium-ion batteries(LIBs)with layered high-nickel oxide cathodes(LiNi_(x)Co_(y)Mn_(1-x-y)O_(2),x≥0.8)show great promise in consumer electronics and vehicular applications.However,LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)faces challenges related to capacity decay caused by residual alkalis owing to high sensitivity to air.To address this issue,we propose a hazardous substances upcycling method that fundamentally mitigates alkali content and concurrently induces the emergence of an anti-air-sensitive layer on the cathode surface.Through the neutralization of polyacrylic acid(PAA)with residual alkalis and then coupling it with 3-aminopropyl triethoxysilane(KH550),a stable and ion-conductive cross-linked polymer layer is in situ integrated into the LiNi_(0.89)Co_(0.06)Mn_(0.05)O_(2)(NCM)cathode.Our characterization and measurements demonstrate its effectiveness.The NCM material exhibits impressive cycling performance,retaining 88.4%of its capacity after 200 cycles at 5 C and achieving an extraordinary specific capacity of 170.0 mA h g^(-1) at 10 C.Importantly,this layer on the NCM efficiently suppresses unfavorable phase transitions,severe electrolyte degradation,and CO_(2)gas evolution,while maintaining commendable resistance to air exposure.This surface modification strategy shows widespread potential for creating air-stable LiNi_(x)Co_(y)Mn_(1-x-y)O_(2)cathodes,thereby advancing high-performance LIBs. 展开更多
关键词 Lithium-ion batteries Nickel-rich layered cathode Residual alkalis Cross-linked polyme rmodification Airsensitivity
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Dissolvable temporary barrier:a novel paradigm for flexible hydrogel patterning in organ-on-a-chip models
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作者 ding wang Qinyu Li +5 位作者 Chenyang Zhou Zhangjie Li Kangyi Lu Yijun Liu Lian Xuan Xiaolin wang 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第2期153-166,共14页
A combination of hydrogels and microfluidics allows the construction of biomimetic three-dimensional(3D)tissue models in vitro,which are also known as organ-on-a-chipmodels.The hydrogel patterningwith awell-controlled... A combination of hydrogels and microfluidics allows the construction of biomimetic three-dimensional(3D)tissue models in vitro,which are also known as organ-on-a-chipmodels.The hydrogel patterningwith awell-controlled spatial distribution is typically achieved by embedding sophisticated microstructures to act as a boundary.However,these physical barriers inevitably expose cells/tissues to a less physiologically relevant microenvironment than in vivo conditions.Herein,we present a novel dissolvable temporary barrier(DTB)strategy that allows robust and flexible hydrogel patterning with great freedom of design and desirable flow stimuli for cellular hydrogels.The key aspect of this approach is the patterning of a water-soluble rigid barrier as a guiding path for the hydrogel using stencil printing technology,followed by a barrier-free medium perfusion after the dissolution of the DTB.Single and multiple tissue compartments with different geometries can be established using either straight or curved DTB structures.The effectiveness of this strategy is further validated by generating a 3D vascular network through vasculogenesis and angiogenesis using a vascularized microtumor model.As a new proof-of-concept in vasculature-on-a-chip,DTB enables seamless contact between the hydrogel and the culture medium in closed microdevices,which is an improved protocol for the fabrication ofmultiorgan chips.Therefore,we expect it to serve as a promising paradigm for organ-on-a-chip devices for the development of tumor vascularization and drug evaluation in the future preclinical studies. 展开更多
关键词 Dissolvable temporary barrier Hydrogel patterning Microfluidics Organ-on-a-chip Vascularization
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Movement Function Assessment Based on Human Pose Estimation from Multi-View
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作者 Lingling Chen Tong Liu +1 位作者 Zhuo Gong ding wang 《Computer Systems Science & Engineering》 2024年第2期321-339,共19页
Human pose estimation is a basic and critical task in the field of computer vision that involves determining the position(or spatial coordinates)of the joints of the human body in a given image or video.It is widely u... Human pose estimation is a basic and critical task in the field of computer vision that involves determining the position(or spatial coordinates)of the joints of the human body in a given image or video.It is widely used in motion analysis,medical evaluation,and behavior monitoring.In this paper,the authors propose a method for multi-view human pose estimation.Two image sensors were placed orthogonally with respect to each other to capture the pose of the subject as they moved,and this yielded accurate and comprehensive results of three-dimensional(3D)motion reconstruction that helped capture their multi-directional poses.Following this,we propose a method based on 3D pose estimation to assess the similarity of the features of motion of patients with motor dysfunction by comparing differences between their range of motion and that of normal subjects.We converted these differences into Fugl–Meyer assessment(FMA)scores in order to quantify them.Finally,we implemented the proposed method in the Unity framework,and built a Virtual Reality platform that provides users with human–computer interaction to make the task more enjoyable for them and ensure their active participation in the assessment process.The goal is to provide a suitable means of assessing movement disorders without requiring the immediate supervision of a physician. 展开更多
关键词 Human pose estimation 3D pose reconstruction assessment of movement function plane of features of human motion
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饲料添加牛至精油对异育银鲫生长、消化酶活性、肠道组织结构及血液生化指标的影响 被引量:1
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作者 王俊维 丁旺 +4 位作者 陈凯 谢骏 秦婷 潘良坤 习丙文 《淡水渔业》 CSCD 北大核心 2023年第2期69-76,共8页
为研究牛至精油对异育银鲫(Carassius auratus gibelio)生长性能、消化酶活性、肠道组织结构和血液生化指标方面的影响,实验选取平均初始体质量为(37.18±0.26)g的健康异育银鲫630尾,设置0(空白对照)、25、50、100、200、400和800 m... 为研究牛至精油对异育银鲫(Carassius auratus gibelio)生长性能、消化酶活性、肠道组织结构和血液生化指标方面的影响,实验选取平均初始体质量为(37.18±0.26)g的健康异育银鲫630尾,设置0(空白对照)、25、50、100、200、400和800 mg/kg 7个牛至精油添加剂量组,进行池塘网箱养殖8周后采样检测分析。结果显示:添加400和800 mg/kg牛至精油组的增重率、肥满度和特定生长率显著高于空白对照组,且饵料系数显著降低;添加800 mg/kg牛至精油组的增重率、肥满度和特定生长率显著高于25和50 mg/kg牛至精油组。与空白对照组相比,添加200和400 mg/kg牛至精油组的鱼体胰蛋白酶、脂肪酶和α-淀粉酶活性显著升高。其中,α-淀粉酶与脂肪酶活性呈先升高再降低趋势,且均在牛至精油水平为200 mg/kg时达到最大值,并显著高于25和800 mg/kg组,与100和400 mg/kg组之间无显著差异。添加200和400 mg/kg牛至精油组的鱼体后肠的肠壁厚度、肠绒毛高度、肠绒毛宽度和杯状细胞数量均显著高于空白对照组,而添加800 mg/kg牛至精油组鱼体后肠的肠绒毛高度和绒毛宽度显著高于50和200 mg/kg组,与400 mg/kg组之间无显著差异。各实验组的总胆固醇(TC)、甘油三酯(TG)和总胆红素(TBIL)与空白对照组相比均无显著性差异;添加50、100、200、400和800 mg/kg牛至精油组血液中谷草转氨酶(AST)活性显著低于空白对照组,而各实验组之间差异不显著。综上,饲料添加牛至精油能有效提高异育银鲫的生长性能,促进其肠道消化酶活性和改善肠道组织形态结构。综合异育银鲫生长性能、肠道组织结构及消化酶活性和血清生化指标,建议饲料牛至精油添加量为100~400 mg/kg。 展开更多
关键词 异育银鲫(Carassius auratus gibelio) 牛至精油 生长性能 消化酶 肠道组织结构 血清生化
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Initiating Binary Metal Oxides Microcubes Electromagnetic Wave Absorber Toward Ultrabroad Absorption Bandwidth Through Interfacial and Defects Modulation 被引量:1
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作者 Fushan Li Nannan Wu +8 位作者 Hideo Kimura Yuan wang Ben Bin Xu ding wang Yifan Li Hassan Algadi Zhanhu Guo Wei Du Chuanxin Hou 《Nano-Micro Letters》 SCIE EI CAS CSCD 2023年第12期68-81,共14页
Cobalt nickel bimetallic oxides(NiCo_(2)O_(4))have received numerous attentions in terms of their controllable morphology,high temperature,corrosion resistance and strong electromagnetic wave(EMW)absorption capability... Cobalt nickel bimetallic oxides(NiCo_(2)O_(4))have received numerous attentions in terms of their controllable morphology,high temperature,corrosion resistance and strong electromagnetic wave(EMW)absorption capability.However,broadening the absorption bandwidth is still a huge challenge for NiCo_(2)O_(4)-based absorbers.Herein,the unique NiCo_(2)O_(4)@C core-shell microcubes with hollow structures were fabricated via a facile sacrificial template strategy.The concentration of oxygen vacancies and morphologies of the three-dimensional(3D)cubic hollow core-shell NiCo_(2)O_(4)@C framework were effectively optimized by adjusting the calcination temperature.The specially designed 3D framework structure facilitated the multiple reflections of incident electromagnetic waves and provided rich interfaces between multiple components,generating significant interfacial polarization losses.Dipole polarizations induced by oxygen vacancies could further enhance the attenuation ability for the incident EM waves.The optimized NiCo_(2)O_(4)@C hollow microcubes exhibit superior EMW absorption capability with minimum RL(RLmin)of-84.45 dB at 8.4 GHz for the thickness of 3.0 mm.Moreover,ultrabroad effective absorption bandwidth(EAB)as large as 12.48 GHz(5.52-18 GHz)is obtained.This work is believed to illuminate the path to synthesis of high-performance cobalt nickel bimetallic oxides for EMW absorbers with excellent EMW absorption capability,especially in broadening effective absorption bandwidth. 展开更多
关键词 Electromagnetic wave absorber NiCo_(2)O_(4)@C Microcubes Oxygen vacancy Effective absorption bandwidth
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Anthropogenic activity,hydrological regime,and light level jointly influence temporal patterns in biosonar activity of the Yangtze finless porpoise at the junction of the Yangtze River and Poyang Lake,China
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作者 Peng-Xiang Duan Zhi-Tao wang +4 位作者 Tomonari Akamatsu Nick Tregenza Guang-Yu Li Ke-Xiong wang ding wang 《Zoological Research》 SCIE CSCD 2023年第5期919-931,共13页
Under increasing anthropogenic pressure,species with a previously contiguous distribution across their ranges have been reduced to small fragmented populations.The critically endangered Yangtze finless porpoise(Neopho... Under increasing anthropogenic pressure,species with a previously contiguous distribution across their ranges have been reduced to small fragmented populations.The critically endangered Yangtze finless porpoise(Neophocaena asiaeorientalis asiaeorientalis),once commonly observed in the Yangtze River-Poyang Lake junction,is now rarely seen in the river-lake corridor.In this study,static passive acoustic monitoring techniques were used to detect the biosonar activities of the Yangtze finless porpoise in this unique corridor.Generalized linear models were used to examine the correlation between these activities and anthropogenic impacts from the COVID-19 pandemic lockdown and boat navigation,as well as environmental variables,including hydrological conditions and light levels.Over approximately three consecutive years of monitoring(2020–2022),porpoise biosonar was detected during 93%of logged days,indicating the key role of the corridor for finless porpoise conservation.In addition,porpoise clicks were recorded in 3.80%of minutes,while feeding correlated buzzes were detected in 1.23%of minutes,suggesting the potential existence of localized,small-scale migration.Furthermore,both anthropogenic and environmental variables were significantly correlated with the diel,lunar,monthly,seasonal,and annual variations in porpoise biosonar activities.During the pandemic lockdown period,porpoise sonar detection showed a significant increase.Furthermore,a significant negative correlation was identified between the detection of porpoise click trains and buzzes and boat traffic intensity.In addition to water level and flux,daylight and moonlight exhibited significant correlations with porpoise biosonar activities,with markedly higher detections at night and quarter moon periods.Ensuring the spatiotemporal reduction of anthropogenic activities,implementing vessel speed restrictions(e.g.,during porpoise migration and feeding),and maintaining local natural hydrological regimes are critical factors for sustaining porpoise population viability. 展开更多
关键词 Yangtze finless porpoises Yangtze River Poyang Lake Pandemic lockdown Boat traffic Hydrological regime Light level
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Adaptive Multi-Step Evaluation Design With Stability Guarantee for Discrete-Time Optimal Learning Control
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作者 ding wang Jiangyu wang +2 位作者 Mingming Zhao Peng Xin Junfei Qiao 《IEEE/CAA Journal of Automatica Sinica》 SCIE EI CSCD 2023年第9期1797-1809,共13页
This paper is concerned with a novel integrated multi-step heuristic dynamic programming(MsHDP)algorithm for solving optimal control problems.It is shown that,initialized by the zero cost function,MsHDP can converge t... This paper is concerned with a novel integrated multi-step heuristic dynamic programming(MsHDP)algorithm for solving optimal control problems.It is shown that,initialized by the zero cost function,MsHDP can converge to the optimal solution of the Hamilton-Jacobi-Bellman(HJB)equation.Then,the stability of the system is analyzed using control policies generated by MsHDP.Also,a general stability criterion is designed to determine the admissibility of the current control policy.That is,the criterion is applicable not only to traditional value iteration and policy iteration but also to MsHDP.Further,based on the convergence and the stability criterion,the integrated MsHDP algorithm using immature control policies is developed to accelerate learning efficiency greatly.Besides,actor-critic is utilized to implement the integrated MsHDP scheme,where neural networks are used to evaluate and improve the iterative policy as the parameter architecture.Finally,two simulation examples are given to demonstrate that the learning effectiveness of the integrated MsHDP scheme surpasses those of other fixed or integrated methods. 展开更多
关键词 Adaptive critic artificial neural networks Hamilton-Jacobi-Bellman(HJB)equation multi-step heuristic dynamic programming multi-step reinforcement learning optimal control
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Non-solvating fluorosulfonyl carboxylate enables temperature-tolerant lithium metal batteries
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作者 Xianshu wang Junru Wu +8 位作者 Yun Zhao Bin Li Naser Tavajohi Qi Liu Jianguo Duan ding wang Peng Dong Yingjie Zhang Baohua Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第7期287-295,I0007,共10页
Advanced electrolyte engineering is an important strategy for developing high-efficacy lithium(Li)metal batteries(LMBs).Unfortunately,the current electrolytes limit the scope for creating batteries that perform well o... Advanced electrolyte engineering is an important strategy for developing high-efficacy lithium(Li)metal batteries(LMBs).Unfortunately,the current electrolytes limit the scope for creating batteries that perform well over temperature ranges.Here,we present a new electrolyte design that uses fluorosulfonyl carboxylate as a non-solvating solvent to form difluoroxalate borate(DFOB-)anion-rich solvation sheath,to realize high-performance working of temperature-tolerant LMBs.With this optimized electrolyte,favorable SEI and CEI chemistries on Li metal anode and nickel-rich cathode are achieved,respectively,leading to fast Li^(+)transfer kinetics,dendrite-free Li deposition and suppressed electrolyte deterioration.Therefore,Li||LiNi_(0.80)Co_(0.15)Al_(0.05)O_(2)batteries with a thin Li foil(50μm)show a long-term cycling lifespan over 400 cycles at 1C and a superior capacity retention of 90%after 200 cycles at 0.5C under 25℃.Moreover,this electrolyte extends the operating temperature from-10 to 30℃and significantly improve the capacity retention and Coulombic efficiency of batteries are improved at high temperature(60℃).Fluorosulfonyl carboxylates thus have considerable potential for use in high-performance and allweather LMBs,which broadens the new exploring of electrolyte design. 展开更多
关键词 Lithium metal batteries Methyl fluorosulfonyldifluoroacetate Non-solvating Anion-rich solvation Temperature tolerance
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Energy absorption characteristics of novel high-strength and hightoughness steels used for rock support
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作者 ding wang Manchao He +3 位作者 Liangjiu Jia Xiaoming Sun Min Xia Xuchun wang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第6期1441-1456,共16页
Nowadays,the development of novel metallic materials for rock support have attracted research interests since they can significantly improve the deformation and energy absorption capacities of rock bolts.Although prev... Nowadays,the development of novel metallic materials for rock support have attracted research interests since they can significantly improve the deformation and energy absorption capacities of rock bolts.Although previous studies proved the importance and mechanical advantages of utilizing high-strength and high-toughness(HSHT)steels in rock support,there is no systematic analysis to reveal the essential energy absorption parameter and the guidelines for further development of metallic rock support materials.This paper analyzes the energy absorption characteristics of novel HSHT steels(negative Poisson’s ratio(NPR)and twinning-induced plasticity(TWIP)steels)in comparison with conventional rock support materials.A physically based crystal plasticity(CP)model was set up and calibrated to study the effect of strain hardening rate(SHR).Meanwhile,the roles of underlying physical mechanisms,i.e.the dislocation density and twin volume fraction,were studied.The results show that the improvement of energy absorption density(EAD)is essential for further development of rock support materials,besides the increase of energy absorption rate(EAR)for previous development of conventional rock support materials.The increase of EAD requires increases of both strength and deformation capacity of materials.For HSHT steels,the decrease of SHR has a positive effect on the improvement of EAD.In addition,the increase of EAD is followed by the increase of twin volume fraction and the decrease of plastic Poisson’s ratio which can promote deformation plasticity of materials.Meanwhile,the increase of EAR is correlated with the accumulation of dislocation density,which can increase the strength of materials.This paper provides the theoretical basis and guidelines for developing rock support materials in deep underground engineering and other related fields. 展开更多
关键词 Rock support Steel Energy absorption Strain hardening rate(SHR) Crystal plasticity(CP)
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基于热力学计算的炉料脉石相交互作用研究
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作者 潘玉柱 丁望 罗大军 《烧结球团》 北大核心 2023年第2期78-84,共7页
熔滴试验和单颗粒炉料试验表明,不同性质炉料的脉石相之间存在交互作用,最终形成成分均匀的初渣。本文通过使用FactSage热力学计算软件分析不同性质炉料脉石相的熔化及其交互作用机理,阐述不同工艺条件下交互作用对冶炼的影响。研究结... 熔滴试验和单颗粒炉料试验表明,不同性质炉料的脉石相之间存在交互作用,最终形成成分均匀的初渣。本文通过使用FactSage热力学计算软件分析不同性质炉料脉石相的熔化及其交互作用机理,阐述不同工艺条件下交互作用对冶炼的影响。研究结果表明,由于矿相组成不同,球团矿相较烧结矿,其脉石相的液相率较高;球团矿和烧结矿脉石相组成的混合初渣,其液相率高于单一烧结矿脉石相的液相率和球团矿、烧结矿脉石相液相率的加权平均值,这说明交互作用可以促进难熔化的烧结矿脉石相熔化;脉石相的液相率随着FeO质量分数的增加而升高。在当前工艺条件下,高碱度烧结矿搭配酸性炉料比使用熔剂型炉料合理。未来氧气高炉和富氢高炉等高还原势高炉可以大量使用酸性炉料和熔剂型炉料。 展开更多
关键词 炉料 烧结矿 球团矿 脉石相 熔化 交互作用
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高炉高比例块矿炉料运动及分布模拟
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作者 康宏毅 秦江昊 +2 位作者 陈建生 丁望 左海滨 《炼铁》 CAS 北大核心 2023年第5期64-68,共5页
以某1800m^(3)高炉为研究对象,建立炉顶装料系统三维模型,利用离散单元法(DEM)模拟整个装料和布料过程中炉料的运动及分布。模拟结果表明:①块矿主要位于受料斗及料罐的右侧,可以根据装料方式和布料矩阵预测块矿的分布;②当炉料结构为75... 以某1800m^(3)高炉为研究对象,建立炉顶装料系统三维模型,利用离散单元法(DEM)模拟整个装料和布料过程中炉料的运动及分布。模拟结果表明:①块矿主要位于受料斗及料罐的右侧,可以根据装料方式和布料矩阵预测块矿的分布;②当炉料结构为75%烧结矿+5%球团矿+20%块矿时,块矿主要分布于高炉边沿和炉喉径向的中间区域,在高炉中心分布较少,但块矿占比较高,接近40%;③随着块矿比例的增加(8%~25%),虽然高炉半径方向的块矿质量增多,但是块矿在炉喉径向的分布不受影响。 展开更多
关键词 高炉 炉顶装料系统 块矿比例 炉料运动及分布 模拟
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草莓状黄铁矿的形成机制探讨及其对古氧化-还原环境的反演 被引量:10
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作者 王东升 张金川 +4 位作者 李振 仝忠正 牛嘉亮 丁望 张聪 《中国地质》 CAS CSCD 北大核心 2022年第1期36-50,共15页
【研究目的】草莓状黄铁矿广泛存在于现代沉积物和沉积岩中,其成因机制总体上分为有机成因和无机成因两种,尽管两种机制均有理论与实验的支撑,但尚未建立一种具有普遍意义的形成机制。【研究方法】本文对目前草莓状黄铁矿的形成机理、... 【研究目的】草莓状黄铁矿广泛存在于现代沉积物和沉积岩中,其成因机制总体上分为有机成因和无机成因两种,尽管两种机制均有理论与实验的支撑,但尚未建立一种具有普遍意义的形成机制。【研究方法】本文对目前草莓状黄铁矿的形成机理、氧化还原环境的应用及后期环境变化的影响进行了系统的综合研究。【研究结果】不同氧化-还原环境下形成的草莓状黄铁矿在粒径、形态以及硫同位素之间均存在较大的差异,可做为反演古氧化-还原环境的指标。草莓状黄铁矿的微晶尽管与粒径具有一定的正相关性,但是两者在形态演化序列、生长模式、聚集因素等方面与古氧化-还原环境的关系尚不清楚。仅凭草莓状黄铁矿粒径与铬还原法测定的硫同位素反演古氧化-还原环境存在一定的局限性,需要其他指标综合判定,尚需进一步开展草莓状黄铁矿原位硫同位素值与粒径对古氧化-还原环境反演的研究。后期氧化可使草莓状黄铁矿表面化学成分发生变化,但粒径分布依然具有古氧化-还原环境的指示意义。【结论】草莓状黄铁矿的实验模拟、理论体系和多学科交叉的研究中仍存在一些问题,尚需进一步研究。 展开更多
关键词 草莓状黄铁矿 微晶 形成机制 古氧化-还原环境 硫同位素 矿产勘查工程
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北京密云沙厂BIF型铁矿地质地球化学特征与成矿时代 被引量:2
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作者 方同明 孙永华 +5 位作者 程新彬 刘鸿 吴虎峻 魏波 wang Wei ding wang 《地质找矿论丛》 CAS CSCD 2017年第1期42-49,共8页
北京密云沙厂铁矿为产于太古宙密云岩群变质岩系中的鞍山式铁矿,具有条带状铁建造(BIF)特征。矿石主要呈条带状构造,致密块状结构;矿石类型以磁铁石英岩型铁矿石为主,w(Fe)=25%~30%。围岩主要有黑云母(角闪)斜长片麻岩、辉石变粒岩和斜... 北京密云沙厂铁矿为产于太古宙密云岩群变质岩系中的鞍山式铁矿,具有条带状铁建造(BIF)特征。矿石主要呈条带状构造,致密块状结构;矿石类型以磁铁石英岩型铁矿石为主,w(Fe)=25%~30%。围岩主要有黑云母(角闪)斜长片麻岩、辉石变粒岩和斜长角闪岩,局部见英云闪长质片麻岩。对选自黑云斜长片麻岩中的锆石进行U-Pb定年,具有核边结构、Th/U>0.4的锆石其核部2组年龄为2 619Ma±25Ma和2 544Ma±16Ma。锆石的2 619Ma±25Ma年龄代表原岩为基性火山岩的黑云斜长片麻岩的形成年龄,同时也代表火山喷发和沙厂铁矿BIF沉积年龄;2 544 Ma±16 Ma锆石年龄可能代表后期TTG特征的花岗质片麻岩的侵位、叠加改造年龄。岩石的主、微量元素特征表明黑云斜长片麻岩富集Rb、Ba、Sr,亏损Th、U,表明沙厂BIF沉积时可能存在新太古代(约2 550 Ma)地壳增生事件。认为沙厂铁矿属Algoma型BIF,是新太古代末华北陆块初步克拉通化和大规模岩浆热事件的代表之一。 展开更多
关键词 密云沙厂铁矿 条带状铁建造(BIF) 锆石U-PB年龄 黑云斜长片麻岩 北京市
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一种全自动三辊闸机芯设计 被引量:3
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作者 丁旺 徐骏善 《机械制造与自动化》 2018年第2期57-60,共4页
为解决传统三辊闸在运用时需要人为推动闸杆使其通过,影响流通量的不足,设计了一套全自动三辊闸机芯。针对机芯转速恒定时,行人仍想快速通过以及在通道上停留的问题,在机械结构上直接给予解决。并基于单片机系统完成其控制方案设计,最... 为解决传统三辊闸在运用时需要人为推动闸杆使其通过,影响流通量的不足,设计了一套全自动三辊闸机芯。针对机芯转速恒定时,行人仍想快速通过以及在通道上停留的问题,在机械结构上直接给予解决。并基于单片机系统完成其控制方案设计,最后进行样机调试。结果表明:该全自动三辊闸机芯能够显著提高通过率,最高通过率达35人/min,并保证行人停留通道时的安全。 展开更多
关键词 三辊闸 全自动机芯 设计 机械结构 控制方案
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非对称创新:中国企业的创新追赶之路 被引量:19
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作者 魏江 王丁 刘洋 《管理学季刊》 2020年第2期46-59,143,共15页
在核心技术和战略性资源缺失的情境下,后发中国企业是如何一步一步实现创新追赶的?我们在长期研究后提出"非对称创新"理论,来概括创新追赶过程和核心理论逻辑。我们认为后发企业在独特的市场型态、制度型态、技术体制三大情境... 在核心技术和战略性资源缺失的情境下,后发中国企业是如何一步一步实现创新追赶的?我们在长期研究后提出"非对称创新"理论,来概括创新追赶过程和核心理论逻辑。我们认为后发企业在独特的市场型态、制度型态、技术体制三大情境下,探索了与先发国家不同的中国企业追赶路径,由此形成了后发企业非对称创新追赶的理论逻辑。研究认为,非对称资源本身不能带来竞争优势,中国企业需要构建非对称创新能力,即以特定实践将非对称资源嵌入组织流程,转化为有价值的资源过程和组织惯例。进一步,我们从学习机制设计、组织架构设计、治理制度设计和追赶路径设计几个角度初步探索了中国企业如何构建非对称创新能力的战略,并提出了未来研究方向。 展开更多
关键词 非对称创新 创新追赶路径 中国式创新
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表面硬质涂层厚度检测方法研究 被引量:2
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作者 丁旺 王春花 +2 位作者 孟峰 付莉莉 钱闯 《现代车用动力》 2018年第3期57-60,共4页
介绍了表面硬质涂厚度检测的5种方法及其检测原理,并对类金刚石(DLC)涂层进行了厚度的检测试验,结果表明该5种检测方法都可以用来检测DLC涂层的厚度。通过5种涂层厚度测量方法的对比分析,确定了不同零件状态下DLC涂层厚度的检测方法。
关键词 类金刚石涂层 厚度 检测原理 检测方法 比较分析
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表面硬质涂层硬度检测方法研究 被引量:1
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作者 丁旺 付莉莉 王春花 《现代车用动力》 2019年第2期51-54,共4页
介绍了表面硬质涂层硬度的检测方法,并分别利用显微硬度计和纳米压入仪对类金刚石(DLC)涂层进行了硬度检测试验,运用Jonsson-Hogmark提出的显微硬度模型进行了涂层本征硬度的推算,并与纳米压入硬度进行了对比分析,结果表明,在加载力为1 ... 介绍了表面硬质涂层硬度的检测方法,并分别利用显微硬度计和纳米压入仪对类金刚石(DLC)涂层进行了硬度检测试验,运用Jonsson-Hogmark提出的显微硬度模型进行了涂层本征硬度的推算,并与纳米压入硬度进行了对比分析,结果表明,在加载力为1 N时,两者具有较好的一致性,推算结果可信。 展开更多
关键词 高压共轨系统 类金刚石涂层 硬度 纳米压入 显微硬度
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牛至精油在水产养殖中的应用研究进展 被引量:5
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作者 丁旺 习丙文 +2 位作者 陈凯 谢骏 潘良坤 《江苏农业科学》 北大核心 2021年第4期8-12,共5页
牛至精油是从唇形科植物牛至中发现的一种挥发性精油,在食品抗菌防腐保鲜、畜牧养殖生产中都有广泛应用。随着管理部门和社会对绿色健康养殖、水产品质量及安全问题日益重视,药用植物资源的开发利用在水产养殖中具有广阔的发展空间。本... 牛至精油是从唇形科植物牛至中发现的一种挥发性精油,在食品抗菌防腐保鲜、畜牧养殖生产中都有广泛应用。随着管理部门和社会对绿色健康养殖、水产品质量及安全问题日益重视,药用植物资源的开发利用在水产养殖中具有广阔的发展空间。本文在目前研究基础上对牛至精油的特性及其在水产动物生产性能、免疫、抗病等方面的作用进行综述,并探讨牛至精油应用中存在的问题,为其在水产养殖中的应用提供参考。 展开更多
关键词 牛至精油 抑菌 抗氧化 生长 水产动物
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