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Preparation of sodium molybdate from molybdenum concentrate by microwave roasting and alkali leaching

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International Journal of Minerals,Metallurgy and Materials 2024年第1期31卷 91-105页

作者： Fengjuan Zhang Chenhui Liu Srinivasakannan Chandrasekar Yingwei Li Fuchang Xu School of Chemistry and Environment Yunnan Minzu UniversityKunming 650500China Chemical Engineering Department Khalifa UniversityAbu DhabiUAE yunnan Zhong Tai Technology Co. Ltd.Kunming 650500China yunnan Yongchang Silicon Industry Co. Ltd.Baoshan 678000China

The preparation process of sodium molybdate has the disadvantages of high energy consumption,low thermal efficiency,and high raw material requirement of molybdenum trioxide,in order to realize the green and efficient development of molybdenum concentrate resources,this paper proposes a new process for efficient recovery of molybdenum from molybdenum concentrate and preparation of sodium molybdate by microwave-enhanced roasting and alkali leaching.Thermodynamic analysis indicated the feasibility of oxidation roasting of molybdenum concentrate.The effects of roasting temperature,holding time,and power-to-mass ratio on the oxidation product and leaching product sodium molybdate (Na_(2)MoO_(4)·2H_(2)O) were investigated.Under the optimal process conditions:roasting temperature of 700℃,holding time of 110 min,and power-to-mass ratio of 110 W/g,the molybdenum state of existence was converted from MoS_(2) to Mo O3.The process of preparing sodium molybdate by alkali leaching of molybdenum calcine was investigated,the optimal leaching conditions include a solution concentration of 2.5 mol/L,a liquid-to-solid ratio of 2 mL/g,a leaching temperature of 60℃,and leaching solution termination at pH 8.The optimum conditions result in a leaching rate of sodium molybdate of 96.24%.Meanwhile,the content of sodium molybdate reaches 94.08wt%after leaching and removing impurities.Iron and aluminum impurities can be effectively separated by adjusting the pH of the leaching solution with sodium carbonate solution.This research avoids the shortcomings of the traditional process and utilizes the advantages of microwave metallurgy to prepare high-quality sodium molybdate,which provides a new idea for the highvalue utilization of molybdenum concentrate.

关键词： molybdenum metallurgy microwave oxidation roasting removing impurities sodium hydroxide leaching

Efficient optimization of electron transfer pathway by constructing phosphide/ceria interface boosts seawater hydrogen production

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Journal of Energy Chemistry 2024年第8期95卷 490-498页

作者： Yifan Zhao Lingfeng Yang Youyu Long Min Xi Anran Chen Hua Zhang School of Materials and Energy Yunnan University Electron Microscopy Centre of yunnan university Yunnan University

Developing efficient and durable hydrogen evolution reaction（HER） electrocatalysts is one of the most important issues for the commercialization of seawater electrolysis,but it remains challenging.Here,we report a CeO2-CoP nanoneedle array catalyst loaded on Ti mesh（CeO2-CoP/TM） with workfunction-induced directional charge transport properties.The CeO2-CoP/TM catalyst showed superior HER catalytic activity and stability,with over potentials of 41 and 60 mV to attain 10 mA cm-2,in 1 M KOH and 1 M KOH+seawater electrolyte,respectively.Experimental results and theoretical calculations reveal that the work function drives the charge transfer from CeO2to CoP,which effectively balances the electronic density of CoP and CeO2,optimizes the d-band center,and accelerates the water activation kinetics,thus enhancing the HER activity.The solar-driven water electrolysis device displays a high and stable solar-to-hydrogen conversion efficiency of 19.6%.This study offers a work function-induced directional charge transport strategy to design efficient and durable catalysts for hydrogen production.

关键词： Charge transport Heterostructure Seawater splitting Solar-to-hydrogen Work function

Feedback of Efficient Shock Acceleration on Magnetic-field Structure Inside Young Type Ia Supernova Remnants

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Research in Astronomy and Astrophysics 2024年第6期24卷 236-246页

作者： Jun-Yu Shen Bi-Wen Bao Li Zhang Department of Astronomy Key Laboratory of Astroparticle Physics of Yunnan Province Yunnan University Key Laboratory of Statistical Modeling and Data Analysis of yunnan Province Yunnan University

Using an effective adiabatic index γeffto mimic the feedback of efficient shock acceleration, we simulate the temporal evolution of a young type Ia supernova remnant （SNR） with two different background magnetic field（BMF） topologies:a uniform and a turbulent BMF. The density distribution and magnetic-field characteristics of our benchmark SNR are studied with two-dimensional cylindrical magnetohydrodynamic simulations. When γeffis considered, we find that:（1） the two-shock structure shrinks and the downstream magnetic-field orientation is dominated by the Rayleigh–Taylor instability structures;（2） there exists more quasi-radial magnetic fields inside the shocked region; and （3） inside the intershock region, both the quasi-radial magnetic energy density and the total magnetic energy density are enhanced:in the radial direction, with γeff=1.1, they are amplified about 10–26 times more than those with γeff=5/3. While in the angular direction, the total magnetic energy densities could be amplified about 350 times more than those with γeff=5/3, and there are more grid cells within the intershock region where the magnetic energy density is amplified by a factor greater than 100.

关键词： ISM: magnetic fields ISM: supernova remnants magnetohydrodynamics (MHD) methods: numerical

Chemical profiling of principle active and toxic constituents in herbs containing aristolochic acids

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Chinese Herbal Medicines 2024年第2期16卷 293-300页

作者： Lijun Yue Kaijun Yang Feng Jiang Shuai Dong Kang Yang Dan Zhu School of Pharmacy Minzu University of ChinaBeijing 100081China Key Laboratory of Ethnomedicine Ministry of Education Minzu University of ChinaBeijing 100081China Hospital of minzu university of China Beijing 100081China

Objective:To clear the amounts of the principal active/toxic components in herbs containing aristolochic acids(HCAAs),which are still used as medicine and/or seasoning in many ethnic minority areas of China.Methods:In this study,six major active and toxic components in HCAAs were extracted with ultrasonic extraction.With 6-O-methyl guanosine as internal standard,the target compounds were analyzed qualitatively and quantitatively by using ultrahigh performance liquid chromatography-electrospray ionization-tandem mass spectrometry(UPLC-ESI-MS/MS)with multiple reaction monitoringinformation dependent acquisition-enhanced production ion scanning mode(MRM-IDA-EPI)combined with dynamic background subtraction(DBS)function.Results:The method showed good linearity in the linear range of the six analytes.The limit range of detection was from 0.01 ng/mL to 0.27 ng/mL.All of the detection repeatability,extraction repeatability and accuracy of the method were good.After extraction,the samples remained stable at 15℃ within 24 h.Six analytes were all found in samples except aristolactam(AL)in sample 2,and the contents varied greatly.The contents of these compounds decreased in fruits,leaves and stems of Aristolochia delavayi successively.Conclusion:This method has the advantages of less sample dosage,simple operation,short analysis cycle,high sensitivity,specificity and accuracy.It laid a good foundation for guiding the safety of HCAAs,the indepth study of pharmacological and toxicological effects and the scientific and standardized processing and compatibility of HCAAs.

关键词： aristolactam aristolochic acids chemical profiling herbs containing aristolochic acids ultrahigh performance liquid chromatography-electrospray ionizationtandem mass spectrometry(UPLC-ESI-MS/MS)

Genetic and immunologic characteristics of colorectal cancer patients with KRAS mutations and predictive significance of tumor immune microenvironment in adjuvant chemotherapy

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Genes & Diseases 2024年第3期11卷 43-46页

作者： Zhengqi Wen Wenliang Li Chengmin Shi Junrui Ma Sihui Zhao Ruize Zhou Xihong Liu Rong Yang Zhiping Zhang Hushan Zhang Bo Li Department of Oncology The First Affiliated Hospital of Kunming Medical UniversityKunmingYunnan 650032China The Third Affliated Hospital of Kunming Medical university(yunnan Cancer Center) KunmingYunnan 650021China Gastrointestinal and Hernia Surgery The First Affiliated Hospital of Kunming Medical UniversityKunmingYunnan 650032China School of Nursing Yunnan University of Chinese MedicineKunmingYunnan 650022China Department of General Surgery The First People's Hospital of Yunnan ProvinceKunmingYunnan 650000China Department of General Surgery The Affiliated Hospital of Yunnan UniversityYunnan 650011China Medical Department 3D Medicines Inc.Shanghai 201114China Zhaotong Health Vocational College ZhaotongYunnan 657000China

Colorectal cancer(CRC)is one of the most common cancers around the world,and it is one of the leading causes of cancer-related death.1 Although anti-EGFR therapy and immune checkpoint inhibitor(ICl)therapy are becoming more and more important for colorectal therapy,however,clinical outcomes of current treatments for metastatic CRC,especially with ICls,have been shown to be affected by the status of KRAS.Therefore,KRAS mutation status detection has become a very important diagnostic factor for managing metastatic CRC patients.

关键词： KRAS colorectal patients

Evolution and conservation genetics of pangolins

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Integrative Zoology 2024年第3期19卷 426-441页

作者： Tongtong GU Jingyang HU Li YU State Key Laboratory for Conservation and Utilization of Bio-Resource in yunnan School of Life SciencesYunnan UniversityKunmingChina

Pangolins(Pholidota,Manidae)are classified as an evolutionarily distinct and globally endangered mammal due to their unique morphology(nail-like scales and a myrmecophagous diet)and being the victim of heavy poaching and worldwide trafficking.As such,pangolins serve as a textbook example for studying the special phenotypic evolutionary adaptations and conservation genetics of an endangered species.Recent years have demonstrated significant advancements in the fields of molecular genetics and genomics,which have translated to a series of important research achievements and breakthroughs concerning the evolution and conservation genetics of pangolins.This review comprehensively presents the hitherto advances in phylogeny,adaptive evolution,conservation genetics,and conservation genomics that are related to pangolins,which will provide an ample understanding of their diversity,molecular adaptation mechanisms,and evolutionary potentials.In addition,we highlight the priority of investigating species/population diversity among pangolins and suggest several avenues of research that are highly relevant for future pangolin conservation.

关键词： adaptive evolution conservation genetics conservation genomics pangolins phylogeny

What is the Role of Gravity, Turbulence and Magnetic Fields in High-mass Star Formation Clouds?

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Research in Astronomy and Astrophysics 2024年第6期24卷 23-29页

作者： An-Xu Luo Hong-Li Liu Guang-Xing Li Sirong Pan Dong-Ting Yang School of Physics and Astronomy Yunnan University South-Western Institute for Astronomy Research Yunnan University

To explore the potential role of gravity,turbulence and magnetic fields in high-mass star formation in molecular clouds,this study revisits the velocity dispersion–size （σ–L） and density–size （ρ–L） scalings and the associated turbulent energy spectrum using an extensive data sample.The sample includes various hierarchical density structures in high-mass star formation clouds,across scales of 0.01–100 pc.We observe σ∝L0.26and ρ∝L-1.54scalings,converging toward a virial equilibrium state.A nearly flat virial parameter–mass (αvir-M) distribution is seen across all density scales,with αvirvalues centered around unity,suggesting a global equilibrium maintained by the interplay between gravity and turbulence across multiple scales.Our turbulent energy spectrum (E（k）)analysis,based on theσ–L andρ–L scalings,yields a characteristic E（k）∝k-1.52.These findings indicate the potential significance of gravity,turbulence,and possibly magnetic fields in regulating dynamics of molecular clouds and high-mass star formation therein.

关键词： ISM: clouds stars: formation stars: kinematics and dynamics

Thoracic spinal cord injury and paraplegia caused by intradural cement leakage after percutaneous kyphoplasty: A case report

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World Journal of Clinical Cases 2024年第10期12卷 1837-1843页

作者： Zi Mao Zhi-Hong Xiong Jun-Feng Li Department of Pain Management The Affiliated Hospital of Yunnan UniversityKunming 650000Yunnan ProvinceChina Department of Medical Administration The Affiliated Hospital of Yunnan UniversityKunming 650000Yunnan ProvinceChina

BACKGROUND Percutaneous kyphoplasty(PKP)is a pivotal intervention for osteoporotic fractures,pathological vertebral compression fractures,and vertebral bone tumors.Despite its efficacy,the procedure presents challenges,notably complications arising from intradural cement leakage.Timely and accurate diagnosis,coupled with emergent intervention is imperative to improve patient prognosis.This case report illuminates the intricacies and potential complications associated with PKP,emphasizing the critical need for vigilant monitoring,prompt diagnosis,and immediate intervention to mitigate adverse outcomes.CASE SUMMARY A 58-year-old male patient,experiencing a T7 osteoporosis-related pathological compression fracture,underwent PKP at a local hospital.Two weeks postprocedure,the patient developed paraplegic and dysuric symptoms,necessitating emergency decompression surgery.Gradual improvement was achieved,marked by the restoration of muscle strength,sensation,and mobility.CONCLUSION PKP Intradural cement leakage following PKP is unusual and potentially fatal.Prompt imaging examinations,urgent evaluation,and the decompression surgery are essential,which help alleviate symptoms associated with spinal damage,markedly improving the overall prognosis.

关键词： Percutaneous kyphoplasty Intradural cement leakage Complication Decompression surgery Case report

Data-driven Surrogate-assisted Method for High-dimensional Multi-area Combined Economic/Emission Dispatch

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Journal of Modern Power Systems and Clean Energy 2024年第1期12卷 52-64页

作者： Chenhao Lin Huijun Liang Aokang Pang Jianwei Zhong Yongchao Yang the College of Intelligent Systems Science and Engineering Hubei Minzu UniversityEnshiChina

Multi-area combined economic/emission dispatch(MACEED)problems are generally studied using analytical functions.However,as the scale of power systems increases,ex isting solutions become time-consuming and may not meet oper ational constraints.To overcome excessive computational ex pense in high-dimensional MACEED problems,a novel data-driven surrogate-assisted method is proposed.First,a cosine-similarity-based deep belief network combined with a back-propagation(DBN+BP)neural network is utilized to replace cost and emission functions.Second,transfer learning is applied with a pretraining and fine-tuning method to improve DBN+BP regression surrogate models,thus realizing fast con struction of surrogate models between different regional power systems.Third,a multi-objective antlion optimizer with a novel general single-dimension retention bi-objective optimization poli cy is proposed to execute MACEED optimization to obtain scheduling decisions.The proposed method not only ensures the convergence,uniformity,and extensibility of the Pareto front,but also greatly reduces the computational time.Finally,a 4-ar ea 40-unit test system with different constraints is employed to demonstrate the effectiveness of the proposed method.

关键词： Multi-area combined economic/emission dispatch high-dimensional power system deep belief network data driven transfer learning