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Thermal decomposition mechanism and kinetics of bastnaesite in suspension roasting process:A comparative study in N_(2) and air atmospheres

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Journal of Rare Earths 2024年第9期42卷 1809-1816,I0006页

作者： Wenbo Li Jijia Chen Shaokai Cheng Junyan Sun xiaolong zhang School of Resources and Civil Engineering Northeastern UniversityShenyang110819China National-Local Joint Engineering Research Center of High-Efficient Exploitation Technology for Refractory Iron Ore Resources Shenyang110819China

To investigate the thermal decomposition behavior and reaction kinetics of bastnaesite in suspension roasting,the gas and solid products of bastnaesite roasted in N2 and air atmospheres were examined using a gas analyzer,X-ray diffraction(XRD),scanning electron microscopy(SEM),and energy dispersive spectrometry(EDS).Subsequently,the kinetic parameters of bastnaesite in the suspension roasting process were derived and calculated using the isothermal *** results show that the decomposition product of bastnaesite in N_(2) is ***,once the roasting temperature exceeds 600℃,CO is generated in addition to CO_(2),and all the XRD diffraction peaks of CeOF are shifted to the right,indicating that CO_(2) can oxidize CeOF and lead to the transformation of Ce(Ⅲ) into Ce(Ⅳ).When roasted in air,the decomposition product CeOF can be completely converted to CeF3 and Ce_(7)O_(12) as it easily ***,the reaction rate of bastnaesite in air is higher than that of N_(2),and the starting reaction temperature is lower than that of N_(2).A large number of irregular cracks and holes appear on the surface of solid-phase products following suspension roasting,which are due to the thermal decomposition of bastnaesite that produces CO_(2) as well as the reconstruction of the lattice of the solid-phase *** reaction kinetic model of bastnaesite roasted in N_(2)(temperature range 600-750℃) and air(temperatu re range 500-575℃) confo rms to the A_(3/2) model with the mechanism function G(α)=-ln(1-α)^(2/3),and the reaction activation energy is 59.78 kj/mol and lnA is 1.65 s^(-1) in N_(2) *** air,the reaction activation energy is 100.30 kj/mol and lnA is 9.63 s^(-1).

关键词： Rare earths Bastnaesite Suspension roasting Thermal decomposition mechanism Reaction kinetics

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Prediction of maximum upward displacement of shield tunnel linings during construction using particle swarm optimization-random forest algorithm

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第1期25卷 1-17页

作者： Xiaowei YE xiaolong zhang Yanbo CHEN Yujun WEI Yang DING MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang UniversityHangzhou310058China Department of Civil Engineering Zhejiang UniversityHangzhou310058China Zhejiang Engineering Research Center of Intelligent Urban Infrastructure Hangzhou City UniversityHangzhou310015China

During construction,the shield linings of tunnels often face the problem of local or overall upward movement after leaving the shield tail in soft soil areas or during some large diameter shield *** floating will increase the initial stress on the segments and bolts which is harmful to the service performance of the *** this study we used a random forest(RF)algorithm combined particle swarm optimization(PSO)and 5-fold cross-validation(5-fold CV)to predict the maximum upward displacement of tunnel linings induced by shield tunnel *** mechanism and factors causing upward movement of the tunnel lining are comprehensively *** input variables were selected according to results from analysis of influencing *** prediction performance of two models,PSO-RF and RF(default)were *** Gini value was obtained to represent the relative importance of the influencing factors to the upward displacement of *** PSO-RF model successfully predicted the maximum upward displacement of the tunnel linings with a low error(mean absolute error(MAE)=4.04 mm,root mean square error(RMSE)=5.67 mm)and high correlation(R^(2)=0.915).The thrust and depth of the tunnel were the most important factors in the prediction model influencing the upward displacement of the tunnel linings.

关键词： Random forest(RF) Particle swarm optimization(PSO) Upward displacement of lining Machine learning prediction Shieldtunneling construction

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Recent process developments in beneficiation and metallurgy of rare earths:A review

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Journal of Rare Earths 2024年第4期42卷 629-642页

作者： Shaokai Cheng Wenbo Li Yuexin Han Yongsheng Sun Peng Gao xiaolong zhang School of Resources and Civil Engineering Northeastern UniversityShenyang110819China National-local Joint Engineering Research Center of High-efficient Exploitation Technology for Refractory Iron Ore Resources Shenyang110819China

Rare earth elements(REEs)are irreplaceable materials supporting low-carbon technology and equip-ment,and their commercial demand and strategic position are becoming increasingly *** the continuous depletion of rare earth(RE)resources,developing high-efficiency beneficiation and eco-friendly metallurgical processes has attracted widespread *** paper reviews the major minerals exploited for RE production and their deposits,as well as the beneficiation and metallurgical processes of RE ***,monazite,mixed RE ores,and ion-adsorption clays are the main raw materials in the world to ***-bearing ores(except ion-adsorption minerals)are generally beneficiated by flotation,gravity and magnetic separation *** mainstream metallurgical processes for bastnaesite,monazite and mixed RE concentrates are oxidation roasting-HCl leaching,caustic soda decomposition and high-temperature concentrated sulfuric acid roasting,***-adsorption clays are directly processed by in situ leaching-precipitation/solvent *** achieve the sustainable development of RE resources,it is essential to further explore innovative techniques to achievecomprehensive utilization and cleaner production.

关键词： Rare earths Beneficiation processes Metallurgical processes Cleaner production

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Multilevel Micro Structures of the Clam Make the Sealing Even Tighter

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Journal of Bionic Engineering 2024年第3期21卷 1442-1452页

作者： Daobing Chen xiaolong zhang Junqiu zhang Zhiwu Han Ruteng Wang Zhen Lin Yifeng Lei Longjian Xue Sheng Liu The Institute of Technological Science Wuhan UniversityWuhan430072China School of Power and Mechanical Engineering Wuhan UniversityWuhan430072China The Key Laboratory of Bionic Engineering(Ministry of Education) Jilin UniversityChangchun130022China Institute of Structured and Architected Materials Liaoning Academy of MaterialsShenyang110167China

Excellent fluid sealing performance is crucial to ensuring the safety of important equipment,especially in aerospace field,such as space capsule and fuel *** frequently opening and closing of the sealing devices is particularly *** by this background,clams(Mactra chinensis)which can open and close their double shells with superior sealing performance,are studied in this ***,we show that the clam’s sealing ability is the result of its unique multilevel intermeshing microstructures,including hinge teeth and *** microstructures,which resemble gear teeth,engage with each other when the shell closes,forming a tight structure that prevents the infiltration of water from the ***,the presence of micron blocks prevents the penetration of finer *** simulation results of the bionic end seal components show that the multilevel microstructure has a superior sealing *** research is expected to be applied to undersea vehicles that require frequent door opening and closing.

关键词： Multilevel micro structures Opening and closing components Clam Sealing Bionic

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Yanggan Jiangmei Formula alleviates hepatic inflammation and lipid accumulation in non-alcoholic steatohepatitis by inhibiting the NF-κB/NLRP3 signaling pathway

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Chinese Journal of Natural Medicines 2024年第3期22卷 224-234页

作者： WU Yuanyuan ZHOU Jingwen ZUO Xinchen KUANG Yufeng SUN Lixia zhang xiaolong The First Clinical Medical College Nanjing University of Chinese MedicineNanjing 210023China The Affiliated Hospital of Nanjing University of Chinese Medicine Jiangsu Province Hospital of Chinese MedicineNanjing 210029China

The role of NF-κB and the NLRP3 inflammasome in the chronic inflammatory microenvironment of non-alcoholic steatohepatitis(NASH)has been posited as *** Yanggan Jiangmei Formula(YGJMF)has shown promise in ameliorating hepatic steatosis in NASH patients,yet its pharmacological mechanisms remain largely *** study was conducted to investigate the efficacy of YGJMF in NASH and to elucidate its pharmacological *** simulate NASH both in vivo and in vitro,high-fat-diet(HFD)rats and HepG2 cells stimulated with free fatty acids(FFAs)were *** severity of liver injury and lipid deposition was assessed using serum indicators,histopathological staining,micro-magnetic resonance imaging(MRI),and the liver-tomuscle signal intensity ratio(SIRL/M).Furthermore,a combination of enzyme-linked immunosorbent assay(ELISA),immunohistochemistry(IHC),immunofluorescence,real-time quantitative polymerase chain reaction(RT-qPCR),and Western blotting analyses was employed to investigate the NF-κB/NLRP3 signaling pathway and associated cytokine *** results from liver pathology,MRI assessments,and biochemical tests in rat models demonstrated YGJMF’s significant effectiveness in reducing liver damage and lipid ***,YGJMF markedly reduced hepatocyte inflammation by downregulating inflammatory cytokines in both liver tissue and ***,YGJMF was found to disrupt NF-κB activation,consequently inhibiting the assembly of the NLRP3 inflammasome in both the in vitro and in vivo *** preliminary findings of this study suggest that YGJMF may alleviate hepatic steatosis and inhibit the NF-κB/NLRP3 signaling pathway,thereby exerting anti-inflammatory effects in NASH.

关键词： Non-alcoholic steatohepatitis Nuclear factor kappa B NLRP3 inflammasome Yanggan Jiangmei Formula

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Inhibition of proliferation,migration,and invasiveness of bladder cancer cells through SAPCD2 knockdown

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BIOCELL 2024年第1期48卷 97-109页

作者： CHONG SHEN JIAJUN YAN YU REN ZHIRONG ZHU xiaolong zhang SHUIXIANG TAO Department of Urology Shaoxing People’s HospitalShaoxing HospitalZhejiang University School of MedicineShaoxingChina

Introduction:Bladder cancer(BC)has a high incidence and mortality rate *** anaphasepromoting complex domain containing 2(SAPCDC2)is over-expressed in a variety of ***:This study investigated the effects of SAPCD2 knockdown on BC ***:T24 and UMUC3 cell models and the xenografted BC tumor model with SAPCD2 knockdown were established to observe the malignant phenotype of BC cells by cell counting kit-8 assay,colony formation test,wound healing,and Transwell assay,mRNA and proteins expressions were measured with quantitative real-time polymerase chain reaction,western blotting,and tissue *** chloride agonist on the Wnt/β-catenin pathway was used to clarify the molecular mechanism of SAPCD2 ***:SAPCD2 expression was significantly higher in BC cell lines than in SVHUC-1 ***2 knockdown inhibited viability and cloning,hindered the G0/G1 phase of the cell cycle in UMUC3 and T24 cells,and decreased the migration and invasiveness of BC ***2 knockdown inhibited expression levels of cyclin D1,cyclin B1,N-cadherin,vimentin,Snail,β-catenin,c-Myc,and cyclin-dependent kinase 4,while the P21 and E-cadherin were raised by SAPCD2 ***,lithium chloride reversed the effects of SAPCD2 knockdown on the expression levels of the above proteins in UMUC3 and T24 *** vivo,SAPCD2 knockdown inhibited the volume,weight,and expression of Ki-67 andβ-catenin in tumors and increased the E-cadherin ***:SAPCD2 knockdown inhibits the malignant phenotype of BC via a pathway involvingβ-catenin.

关键词： Bladder cancer SAPCD2 β-catenin c-Myc CDK4 Lithium chloride

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Yanggan Jiangmei Formula alleviates hepatic inflammation and lipid accumulation in non-alcoholic steatohepatitis by inhibiting the NF-κB/NLRP3 signaling pathway

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Chinese Journal of Natural Medicines 2024年第03期 224-234页

作者： WU Yuanyuan ZHOU Jingwen ZUO Xinchen KUANG Yufeng SUN Lixia zhang xiaolong The First Clinical Medical College Nanjing University of Chinese Medicine The Affiliated Hospital of Nanjing University of Chinese Medicine Jiangsu Province Hospital of Chinese Medicine

The role of NF-κB and the NLRP3 inflammasome in the chronic inflammatory microenvironment of non-alcoholic steatohepatitis(NASH) has been posited as crucial. The Yanggan Jiangmei Formula(YGJMF) has shown promise in ameliorating hepatic steatosis in NASH patients, yet its pharmacological mechanisms remain largely unexplored. This study was conducted to investigate the efficacy of YGJMF in NASH and to elucidate its pharmacological underpinnings. To simulate NASH both in vivo and in vitro,high-fat-diet(HFD) rats and HepG2 cells stimulated with free fatty acids(FFAs) were utilized. The severity of liver injury and lipid deposition was assessed using serum indicators, histopathological staining, micro-magnetic resonance imaging(MRI), and the liver-tomuscle signal intensity ratio(SIRL/M). Furthermore, a combination of enzyme-linked immunosorbent assay(ELISA), immunohistochemistry(IHC), immunofluorescence, real-time quantitative polymerase chain reaction(RT-qPCR), and Western blotting analyses was employed to investigate the NF-κB/NLRP3 signaling pathway and associated cytokine levels. The results from liver pathology,MRI assessments, and biochemical tests in rat models demonstrated YGJMF's significant effectiveness in reducing liver damage and lipid accumulation. Additionally, YGJMF markedly reduced hepatocyte inflammation by downregulating inflammatory cytokines in both liver tissue and serum. Furthermore, YGJMF was found to disrupt NF-κB activation, consequently inhibiting the assembly of the NLRP3 inflammasome in both the in vitro and in vivo models. The preliminary findings of this study suggest that YGJMF may alleviate hepatic steatosis and inhibit the NF-κB/NLRP3 signaling pathway, thereby exerting anti-inflammatory effects in NASH.

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基于hp-VPINN的反应堆中子扩散计算方法研究

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核动力工程 2024年第2期45卷 53-62页

作者：曾付林张小龙赵鹏程南华大学核科学技术学院湖南衡阳421001

先进的反应堆模拟技术需要基于较少的实际探测数据反演全堆关键参数。针对这一需要,本文基于具有高阶多项式域分解功能的变分残差物理信息神经网络(hp-VPINN)构建计算模型,用于正向、反向求解中子扩散方程。该模型使用神经网络作为试函... 详细信息

先进的反应堆模拟技术需要基于较少的实际探测数据反演全堆关键参数。针对这一需要,本文基于具有高阶多项式域分解功能的变分残差物理信息神经网络(hp-VPINN)构建计算模型,用于正向、反向求解中子扩散方程。该模型使用神经网络作为试函数,并将其代入中子扩散方程形成变分残差作为损失函数进行梯度下降。为了提高求解精度及效率,本文还根据中子扩散方程的物理特性提出了有效增殖系数智能搜索与反演等创新型关键技术,并基于鲸鱼优化算法(WOA)实现了神经网络超参数自优化。最后通过多个算例进行验证,结果表明该方法在具有较高精度的同时,实现了较低的训练数据依赖,为先进反应堆模拟技术提供了一条少量输入数据且较高精度输出的中子扩散求解途径。

关键词：变分残差物理信息神经网络(hp-VPINN) 鲸鱼优化算法(WOA) 中子扩散方程有效增殖系数反应堆模拟技术

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SBA-15分子筛负载对甲苯磺酸催化合成过氧化二异丙苯的性能和反应过程模拟

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高等学校化学学报 2024年第6期45卷 98-106页

作者：张小龙张毅城李庆朝查飞常玥唐小华西北师范大学化学化工学院兰州730070 山东阳谷华泰化工股份有限公司阳谷252300

采用浸渍法制备了SBA-15分子筛负载对甲苯磺酸(TsOH)催化剂TsOH/SBA-15,探究了其催化α-甲基苯乙烯(α-MS)和异丙苯过氧化氢(CHP)反应制备过氧化二异丙苯(DCP)的活性,并对反应过程进行了模拟分析.当进料比n(α-甲基苯乙烯)/n(异丙苯过... 详细信息

采用浸渍法制备了SBA-15分子筛负载对甲苯磺酸(TsOH)催化剂TsOH/SBA-15,探究了其催化α-甲基苯乙烯(α-MS)和异丙苯过氧化氢(CHP)反应制备过氧化二异丙苯(DCP)的活性,并对反应过程进行了模拟分析.当进料比n(α-甲基苯乙烯)/n(异丙苯过氧化氢)=2.0, TsOH/SBA-15用量为CHP质量的0.15%,于44℃反应2.5h, DCP的产率为62.1%.模拟计算结果表明,反应过程有异步协同反应和分步反应两种机理,在异步协同反应中α-MS, CHP和TsOH只需要经过一个过渡态即可完成,而分步反应中反应物需要经过两个过渡态以及一个中间体才能完成,两种路径均涉及2次H^(+)的转移.在44℃下,异步协同反应的反应能垒(ΔG)为121.8 kJ/mol,分步反应中两个过渡态对应的反应能垒分别为74.1和78.3 kJ/mol.

关键词：对甲苯磺酸 SBA-15分子筛过氧化二异丙苯异丙苯过氧化氢反应能垒

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多胎内传感器智能轮胎开发平台设计与侧偏试验研究

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机械工程学报 2024年第8期60卷 245-255页

作者：陶亮唐钰李元强张大山张小龙安徽农业大学工学院合肥230036

轮胎侧偏角的辨识与调控是汽车稳定性控制的关键技术,基于轮胎接地特性来辨识估算轮胎侧偏角是一种新的方法。通过搭建面向胎内多传感器的智能轮胎开发平台,并开展侧偏试验分析基于接地信号的轮胎侧偏特征。首先明确智能轮胎开发平台的... 详细信息

轮胎侧偏角的辨识与调控是汽车稳定性控制的关键技术,基于轮胎接地特性来辨识估算轮胎侧偏角是一种新的方法。通过搭建面向胎内多传感器的智能轮胎开发平台,并开展侧偏试验分析基于接地信号的轮胎侧偏特征。首先明确智能轮胎开发平台的功能及设计要求,搭建系统架构并进行硬件选型,其中胎内传感器包括3个三轴加速度计和3个压电薄膜传感器。其次开发了专用轮辋总成和基于美国NI cRIO的数据采集器,软件基于LabVIEW开发并实现了多通道数据同步和大数据流管控等。最后在Flat Trac台架上进行系统的轮胎侧偏试验。分析发现,在侧偏角达到±3°时加速度计(量程500g)均出现超量程现象,其信号频率主要集中在500~1000 Hz;轮胎中心平面位置加速度计250 Hz内的信号对侧偏角不敏感,但偏离轮胎中心平面其他位置的传感器信号敏感,特别是胎侧位置的径向加速度,其2个尖峰与侧偏角显著相关;轮胎中心平面位置的接地长度与垂直载荷、胎压相关,而与侧偏角无关,但偏离轮胎中心平面其他位置的接地长度对侧偏角敏感,并且垂直载荷越大、胎压越低则影响越明显。开发的智能轮胎开发平台为轮胎接地机理与轮胎侧偏角估算等研究提供了有效手段。

关键词：智能轮胎开发平台集成设计台架试验轮胎侧偏

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