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基于Pro/Mechanism的仿生膝关节优化设计与运动仿真研究 被引量:3
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作者 李燕 《机床与液压》 北大核心 2009年第6期183-185,共3页
设计了用于数字化三维人体模型或假肢的四连杆膝关节,为了达到理想的运动效果,以膝机构瞬心坐标实际值与理想值之差最小,即膝机构的实际瞬心曲线与理想的膝关节瞬心轨迹相一致为目标函数,在五维设计空间中求得一组最优解,利用Pro/E具有... 设计了用于数字化三维人体模型或假肢的四连杆膝关节,为了达到理想的运动效果,以膝机构瞬心坐标实际值与理想值之差最小,即膝机构的实际瞬心曲线与理想的膝关节瞬心轨迹相一致为目标函数,在五维设计空间中求得一组最优解,利用Pro/E具有几何约束和尺寸驱动等参数化设计功能,无需进行烦琐复杂的公式推导即可建立满足约束要求的数学模型,并应用Pro/E的多目标设计研究功能求得满足运动要求的杆件参数,在此基础上进行膝关节机构的三维造型及装配,进而在Pro/Mechanism环境下对仿生膝关节杆机构进行运动仿真。 展开更多
关键词 pro/mechanism 四连杆膝关节 运动仿真 优化设计
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基于Pro/Mechanism的装载机工作装置运动仿真 被引量:7
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作者 陈亮 宋德朝 《机械》 2008年第5期48-50,共3页
在Pro/Engineer环境下,将虚拟样机技术与Pro/Engineer软件相结合,可以进行装载机工作装置虚拟样机的三维实体模型,虚拟装配,动态模拟,干涉检查、运动仿真和动力学分析。本文采用Pro/Mechanism模块进行运动仿真分析,其分析结果对缩短产... 在Pro/Engineer环境下,将虚拟样机技术与Pro/Engineer软件相结合,可以进行装载机工作装置虚拟样机的三维实体模型,虚拟装配,动态模拟,干涉检查、运动仿真和动力学分析。本文采用Pro/Mechanism模块进行运动仿真分析,其分析结果对缩短产品的开发周期,提高设计质量有指导意义。这种基于虚拟样机模型的建模方法,对装载机工作装置的设计具有普遍的适用性,是虚拟样机技术的一个良好应用实例,有很强的实用性,对于设计工作有一定的指导意义。 展开更多
关键词 装载机 工作装置 仿真 pro/E pro/mechanism
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基于Pro/Mechanism的柴油机动力计算
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作者 贾双林 刘荣辉 +1 位作者 张浩 曹硕 《吉林化工学院学报》 CAS 2016年第7期35-40,共6页
以16V 240柴油机为例,使用美国参数技术公司Pro/Engineer大型设计软件的MDX(Mechanism Design extension)CAE模块进行曲柄连杆机构的动力计算,将MDX计算的结果与理论计算的结果进行比较,并且在曲柄连杆机构动力计算的基础上,进行16V240... 以16V 240柴油机为例,使用美国参数技术公司Pro/Engineer大型设计软件的MDX(Mechanism Design extension)CAE模块进行曲柄连杆机构的动力计算,将MDX计算的结果与理论计算的结果进行比较,并且在曲柄连杆机构动力计算的基础上,进行16V240柴油机输出扭矩的计算.计算结果表明基于Pro/Mechanism的柴油机动力计算的方法切实可行. 展开更多
关键词 MDX pro/mechanism 动力计算 CAE 曲柄连杆机构
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基于Pro/Mechanism的曲柄导杆机构运动学仿真 被引量:2
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作者 赵小刚 《广西轻工业》 2011年第10期64-65,共2页
利用Pro/E三维造型建立曲柄导杆机构运动模型,通过Pro/Mechanism对曲柄导杆机构进行运动学仿真,得到了曲柄导杆机构的运动曲线。该方法具有精度高、速度快等特点。
关键词 曲柄导杆机构 运动学 pro/E pro/mechanism
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基于Pro/Mechanism的运动仿真设计 被引量:1
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作者 白晓东 《航天制造技术》 2006年第6期56-57,共2页
结合产品设计过程,提出了一种运动学特性分析的新的设计方法。介绍了机构运动仿真分析在机械设计中的方法和技巧。为机构运动仿真设计提供有益的思路和实践经验。
关键词 pro/mechanism 机构 运动仿真
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用Pro/Mechanism实现复杂凸轮机构的设计及运动分析 被引量:1
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作者 李燕 《机械研究与应用》 2005年第4期110-111,117,共3页
针对复杂平面运动从动件盘形凸轮机构设计的困难,介绍1种利用Pro/Mechanism的强大功能实现复杂凸轮机构的创新设计、运动仿真及运动分析。这种创新方法可以使复杂凸轮机构设计变的快捷、便利。
关键词 平动 凸轮机构 pro/E
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基于Pro/MECHANISM的旋转式压缩机运动仿真机构的建立与分析 被引量:5
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作者 钱珊 《压缩机技术》 2009年第2期6-9,共4页
在旋转式压缩机的开发与设计过程中,滑片与滚套之间是否干涉、滑片行程随时间变化的函数规律往往是设计人员关注的焦点,而常规的设计方法无法动态地解决上述两个问题,运用Pro/E的Mechanism模块所建立的旋转式压缩机运动学仿真机构,不但... 在旋转式压缩机的开发与设计过程中,滑片与滚套之间是否干涉、滑片行程随时间变化的函数规律往往是设计人员关注的焦点,而常规的设计方法无法动态地解决上述两个问题,运用Pro/E的Mechanism模块所建立的旋转式压缩机运动学仿真机构,不但直观、快捷地解决了上述两个问题,从运动的角度保证了压缩机结构设计的合理性与可靠性,同时还为进一步进行动力学分析、敏感度分析和优化设计打下了坚实的基础。 展开更多
关键词 mechanism 旋转式压缩机 运动仿真机构 干涉检查
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Pro/Mechanism对大型装置起升过程的仿真
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作者 孙庆华 刘秀珍 李锋 《起重运输机械》 北大核心 2007年第3期65-67,共3页
关键词 运动仿真 大型装置 pro/ENGINEER 液压系统设计 有效作用面积 三维造型软件 机械装置 驱动方式
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基于Pro/Mechanism齿轮组啮合干涉消除方法的探讨
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作者 李静 赵云龙 《科技创新与应用》 2012年第22期25-26,共2页
本文论述了在Pro/Mechanism软件模块中齿轮组啮合时干涉消除的方法。对齿轮组啮合时干涉产生的原因进行了分析,提出了三种不同的解决方法。这些方法在消除齿轮组啮合干涉方面效果明显。
关键词 pro mechanism 齿轮啮合 干涉消除
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基于Pro/Mechanism的嵌线机构的运动仿真分析
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作者 武小明 臧文涛 +1 位作者 张前卫 关玉明 《自动化应用》 2013年第6期28-30,57,共4页
借助三维软件Pro/E对嵌线机构中工作盘机构(包括齿轮啮合结构)进行三维建模,并在此基础上对嵌线机构进行结构上的干涉检查,进而应用Pro/Mechanism软件对嵌线机构进行运动仿真分析。
关键词 嵌线机构 pro E 运动仿真 pro mechanism
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Drug resistance mechanisms in cancers:Execution of prosurvival strategies 被引量:1
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作者 Pavan Kumar Dhanyamraju 《Journal of Biomedical Research》 CAS CSCD 2024年第2期95-121,共27页
One of the quintessential challenges in cancer treatment is drug resistance.Several mechanisms of drug resistance have been described to date,and new modes of drug resistance continue to be discovered.The phenomenon o... One of the quintessential challenges in cancer treatment is drug resistance.Several mechanisms of drug resistance have been described to date,and new modes of drug resistance continue to be discovered.The phenomenon of cancer drug resistance is now widespread,with approximately 90% of cancer-related deaths associated with drug resistance.Despite significant advances in the drug discovery process,the emergence of innate and acquired mechanisms of drug resistance has impeded the progress in cancer therapy.Therefore,understanding the mechanisms of drug resistance and the various pathways involved is integral to treatment modalities.In the present review,I discuss the different mechanisms of drug resistance in cancer cells,including DNA damage repair,epithelial to mesenchymal transition,inhibition of cell death,alteration of drug targets,inactivation of drugs,deregulation of cellular energetics,immune evasion,tumor-promoting inflammation,genome instability,and other contributing epigenetic factors.Furthermore,I highlight available treatment options and conclude with future directions. 展开更多
关键词 cancer drug resistance mechanismS MICRORNAS treatment strategies
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Mechanism underlying the effects of exercise against type 2 diabetes:A review on research progress 被引量:1
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作者 Chen-Jian Peng Shuo Chen +4 位作者 Su-Ying Yan Jian-Ning Zhao Zhi-Wen Luo Yuan Qian Guo-Liang Zhao 《World Journal of Diabetes》 SCIE 2024年第8期1704-1711,共8页
Exercise has emerged as one of the important and effective non-drug therapies used for management of type 2 diabetes(T2D)in certain nations.The present report summarizes the latest findings from the research on the be... Exercise has emerged as one of the important and effective non-drug therapies used for management of type 2 diabetes(T2D)in certain nations.The present report summarizes the latest findings from the research on the beneficial effect of exercise on T2D.The objectives were to provide references for the theoretical study and the clinical practice of exercise-based management of T2D,in addition to identify the limitations of the existing literature,thereby provide direction for future research in this field. 展开更多
关键词 Type 2 diabetes DIABETES EXERCISE mechanism INFLAMMATION
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Recent research progress in the mechanism and suppression of fusion welding-induced liquation cracking of nickel based superalloys 被引量:1
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作者 Zongli Yi Jiguo Shan +2 位作者 Yue Zhao Zhenlin Zhang Aiping Wu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第5期1072-1088,共17页
Nickel-based superalloys are extensively used in the crucial hot-section components of industrial gas turbines,aeronautics,and astronautics because of their excellent mechanical properties and corrosion resistance at ... Nickel-based superalloys are extensively used in the crucial hot-section components of industrial gas turbines,aeronautics,and astronautics because of their excellent mechanical properties and corrosion resistance at high temperatures.Fusion welding serves as an effective means for joining and repairing these alloys;however,fusion welding-induced liquation cracking has been a challenging issue.This paper comprehensively reviewed recent liquation cracking,discussing the formation mechanisms,cracking criteria,and remedies.In recent investigations,regulating material composition,changing the preweld heat treatment of the base metal,optimizing the welding process parameters,and applying auxiliary control methods are effective strategies for mitigating cracks.To promote the application of nickel-based superalloys,further research on the combination impact of multiple elements on cracking prevention and specific quantitative criteria for liquation cracking is necessary. 展开更多
关键词 nickel-based superalloy fusion welding liquation cracking cracking mechanism cracking suppression
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An Underwater Target Detection Algorithm Based on Attention Mechanism and Improved YOLOv7 被引量:1
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作者 Liqiu Ren Zhanying Li +2 位作者 Xueyu He Lingyan Kong Yinghao Zhang 《Computers, Materials & Continua》 SCIE EI 2024年第2期2829-2845,共17页
For underwater robots in the process of performing target detection tasks,the color distortion and the uneven quality of underwater images lead to great difficulties in the feature extraction process of the model,whic... For underwater robots in the process of performing target detection tasks,the color distortion and the uneven quality of underwater images lead to great difficulties in the feature extraction process of the model,which is prone to issues like error detection,omission detection,and poor accuracy.Therefore,this paper proposed the CER-YOLOv7(CBAM-EIOU-RepVGG-YOLOv7)underwater target detection algorithm.To improve the algorithm’s capability to retain valid features from both spatial and channel perspectives during the feature extraction phase,we have added a Convolutional Block Attention Module(CBAM)to the backbone network.The Reparameterization Visual Geometry Group(RepVGG)module is inserted into the backbone to improve the training and inference capabilities.The Efficient Intersection over Union(EIoU)loss is also used as the localization loss function,which reduces the error detection rate and missed detection rate of the algorithm.The experimental results of the CER-YOLOv7 algorithm on the UPRC(Underwater Robot Prototype Competition)dataset show that the mAP(mean Average Precision)score of the algorithm is 86.1%,which is a 2.2%improvement compared to the YOLOv7.The feasibility and validity of the CER-YOLOv7 are proved through ablation and comparison experiments,and it is more suitable for underwater target detection. 展开更多
关键词 Deep learning underwater object detection improved YOLOv7 attention mechanism
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Overview of the immunological mechanisms in hepatitis B virus reactivation:Implications for disease progression and management strategies 被引量:1
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作者 Hui Ma Qing-Zhu Yan +2 位作者 Jing-Ru Ma Dong-Fu Li Jun-Ling Yang 《World Journal of Gastroenterology》 SCIE CAS 2024年第10期1295-1312,共18页
Hepatitis B virus(HBV)reactivation is a clinically significant challenge in disease management.This review explores the immunological mechanisms underlying HBV reactivation,emphasizing disease progression and manageme... Hepatitis B virus(HBV)reactivation is a clinically significant challenge in disease management.This review explores the immunological mechanisms underlying HBV reactivation,emphasizing disease progression and management.It delves into host immune responses and reactivation’s delicate balance,spanning innate and adaptive immunity.Viral factors’disruption of this balance,as are interac-tions between viral antigens,immune cells,cytokine networks,and immune checkpoint pathways,are examined.Notably,the roles of T cells,natural killer cells,and antigen-presenting cells are discussed,highlighting their influence on disease progression.HBV reactivation’s impact on disease severity,hepatic flares,liver fibrosis progression,and hepatocellular carcinoma is detailed.Management strategies,including anti-viral and immunomodulatory approaches,are critically analyzed.The role of prophylactic anti-viral therapy during immunosuppressive treatments is explored alongside novel immunotherapeutic interventions to restore immune control and prevent reactivation.In conclusion,this compre-hensive review furnishes a holistic view of the immunological mechanisms that propel HBV reactivation.With a dedicated focus on understanding its implic-ations for disease progression and the prospects of efficient management stra-tegies,this article contributes significantly to the knowledge base.The more profound insights into the intricate interactions between viral elements and the immune system will inform evidence-based approaches,ultimately enhancing disease management and elevating patient outcomes.The dynamic landscape of management strategies is critically scrutinized,spanning anti-viral and immunomodulatory approaches.The role of prophylactic anti-viral therapy in preventing reactivation during immunosuppressive treatments and the potential of innovative immunotherapeutic interventions to restore immune control and proactively deter reactivation. 展开更多
关键词 Hepatitis B virus reactivation Immunological mechanisms Disease progression Management strategies Immune response
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Fecal microbiota transplantation for treatment of non-alcoholic fatty liver disease:Mechanism,clinical evidence,and prospect 被引量:1
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作者 Xiao-Xia Qiu Sheng-Li Cheng +4 位作者 Yan-Hui Liu Yu Li Rui Zhang Nan-Nan Li Zheng Li 《World Journal of Gastroenterology》 SCIE CAS 2024年第8期833-842,共10页
The population of non-alcoholic fatty liver disease(NAFLD)patients along with relevant advanced liver disease is projected to continue growing,because currently no medications are approved for treatment.Fecal microbio... The population of non-alcoholic fatty liver disease(NAFLD)patients along with relevant advanced liver disease is projected to continue growing,because currently no medications are approved for treatment.Fecal microbiota transplantation(FMT)is believed a novel and promising therapeutic approach based on the concept of the gut-liver axis in liver disease.There has been an increase in the number of pre-clinical and clinical studies evaluating FMT in NAFLD treatment,however,existing findings diverge on its effects.Herein,we briefly summarized the mechanism of FMT for NAFLD treatment,reviewed randomized controlled trials for evaluating its efficacy in NAFLD,and proposed the prospect of future trials on FMT. 展开更多
关键词 Non-alcoholic fatty liver disease Fecal microbiota transplantation Randomized controlled trial mechanism EFFICACY
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Microdynamic mechanical properties and fracture evolution mechanism of monzogabbro with a true triaxial multilevel disturbance method
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作者 Zhi Zheng Bin Deng +3 位作者 Hong Liu Wei Wang Shuling Huang Shaojun Li 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第3期385-411,共27页
The far-field microdynamic disturbance caused by the excavation of deep mineral resources and underground engineering can induce surrounding rock damage in high-stress conditions and even lead to disasters.However,the... The far-field microdynamic disturbance caused by the excavation of deep mineral resources and underground engineering can induce surrounding rock damage in high-stress conditions and even lead to disasters.However,the mechanical properties and damage/fracture evolution mechanisms of deep rock induced by microdynamic disturbance under three-dimensional stress states are unclear.Therefore,a true triaxial multilevel disturbance test method is proposed,which can completely simulate natural geostress,excavation stress redistribution(such as stress unloading,concentration and rotation),and subsequently the microdynamic disturbance triggering damaged rock failure.Based on a dynamic true triaxial test platform,true triaxial microdynamic disturbance tests under different frequency and amplitudes were carried out on monzogabbro.The results show that increasing amplitude or decreasing frequency diminishes the failure strength of monzogabbro.Deformation modulus gradually decreases during disturbance failure.As frequency and amplitude increase,the degradation rate of deformation modulus decreases slightly,disturbance dissipated energy increases significantly,and disturbance deformation anisotropy strengthens obviously.A damage model has been proposed to quantitatively characterize the disturbance-induced damage evolution at different frequency and amplitude under true triaxial stress.Before disturbance failure,the micro-tensile crack mechanism is dominant,and the micro-shear crack mechanism increases significantly at failure.With the increase of amplitude and frequency,the micro-shear crack mechanism increases.When approaching disturbance failure,the acoustic emission fractal dimension changes from a stable value to local large oscillation,and finally increases sharply to a high value at failure.Finally,the disturbance-induced failure mechanism of surrounding rock in deep engineering is clearly elucidated. 展开更多
关键词 True triaxial disturbance test mechanical properties Fracture evolution mechanism Disturbance-induced damage evolution Failure mechanism and precursor
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Activity-dependent mechanisms of neuroprotection:promising avenues against dementia
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作者 Davide Tampellini 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1409-1410,共2页
The study of the brain and its complex functions is highly fascinating and,at the same time,extremely important.Indeed,furthering our understanding of the biology of neurons and synapses is a prerequisite to uncover t... The study of the brain and its complex functions is highly fascinating and,at the same time,extremely important.Indeed,furthering our understanding of the biology of neurons and synapses is a prerequisite to uncover the mechanisms involved in memory formation and the coordination of movement as well as their alterations occurring in several neurological disorders. 展开更多
关键词 alterations mechanismS NEUROLOGICAL
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Obituary:Prof.Yun Zhang(1963-2023)-A scientist focused on toxins and their underlying mechanisms to decipher human diseases
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作者 Wenhui Lee Ren Lai 《Zoological Research》 SCIE CSCD 2024年第1期230-232,共3页
Prof.Yun Zhang was born on 9 July 1963 in Kunming,Yunnan,China,during a tumultuous period which he often referenced.Throughout his life,he harbored a steadfast belief in using knowledge to unravel the mysteries of hum... Prof.Yun Zhang was born on 9 July 1963 in Kunming,Yunnan,China,during a tumultuous period which he often referenced.Throughout his life,he harbored a steadfast belief in using knowledge to unravel the mysteries of human diseases.His educational journey was marked by frequent changes in schools due to his parents’occupational relocations.However,despite these challenges,he consistently displayed diligence and was admitted to the East China University of Science and Technology,Shanghai,after completing high school in 1980.He remained an active and loyal member of the School of Biotechnology at the university. 展开更多
关键词 admitted harbor mechanismS
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Impact and mechanism of bisphosphonate depressant 1-hydroxypropane-1,1-diphosphonic acid on flotation decalcification of dolomite-rich magnesite ore
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作者 Wengang Liu Xudong Chen +3 位作者 Wenbao Liu Naixu Zhang Yong Mao Ying Guo 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第7期1017-1032,共16页
Given the depletion of high-quality magnesite deposits and the rising demand for high-end magnesium materials,the separation and utilization of high-calcium magnesite ores have become essential.However,the similar sur... Given the depletion of high-quality magnesite deposits and the rising demand for high-end magnesium materials,the separation and utilization of high-calcium magnesite ores have become essential.However,the similar surface properties and solubility of semi-soluble salt-type minerals,pose significant challenges for the utilization of dolomite-rich magnesite resources.In this study,1-hydroxypropane-1,1-di phosphonic acid(HPDP)was identified for the first time as a high-performance depressant for dolomite.Various tests,including contact angle measurements,ζ potential analysis,X-ray photoelectron spectroscopy,and atomic force microscopy,were conducted to elucidate the interfacial interaction mechanisms of HPDP on the surfaces of the two minerals at different scales.Additionally,molecular modeling calculations were used to detail the spatial matching relationship between HPDP and the crystal faces of the two minerals.It was emphasized that HPDP specifically adsorbed onto the dolomite surface by forming calcium phosphonate,ensuring that the dolomite surface remained hydrophilic and sank.Moreover,it was found that the adsorption strength of HPDP on the mineral surfaces depended on the activity of the metal sites and their spatial distribution.These findings provide a theoretical foundation for the molecular design of flotation reagents for high-calcium magnesite ores. 展开更多
关键词 Depressant Interfacial mechanism MAGNESITE DOLOMITE DFT DECALCIFICATION
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