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Enhancement of CaMoO_(4) calcine decomposition and recovery of calcium resource by HCl cycle leaching

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Transactions of Nonferrous Metals Society of China 2022年第4期32卷 1314-1324页

作者： Li ZENG Man WANG Chao XIAO Sheng-xi WU Gui-qing ZHANG wen-juan guan Qing-gang LI Zuo-ying CAO School of Metallurgy and Environment Central South UniversityChangsha 410083China Key Laboratory of Metallurgical Separation Science and Engineering of Non-ferrous Metals Industry Central South UniversityChangsha 410083China National Engineering Laboratory for Efficient Utilization of Refractory Non-ferrous Metals Resources Central South UniversityChangsha 410083China

The thermodynamic equilibrium diagrams of CaMoO_(4)-CaSO_(4)-H_(2)SO_(4)-H_(2)O,CaMoO_(4)-HCl-H_(2)O and CaSO_(4)-CaCl_(2)-HCl-H_(2)O systems at 298 K were *** calculation results demonstrated that HCl displays a much higher solubility of CaSO_(4)than H_(2)SO_(4).The leaching mechanism of Mo from CaMoO_(4)calcine was systematically investigated from the perspective of the micro particle properties *** exhibits an excellent leaching performance for Mo from CaMoO_(4)calcine due to the elimination of surface coating and the dissolution of a mass of Mo embedded in CaSO_(4)*** Mo leaching efficiency of 99.7%was achieved under the optimal conditions of decomposing CaMoO_(4)calcine by 2.4 mol/L HCl with a liquid/solid ratio of 10:1 at 50°C for 60 *** on the experimental results,a highly efficient and green cycle leaching process of molybdenum from molybdenite was proposed,which eliminated surface coating and physical entraining,and converted most of the calcium from CaMoO_(4)calcine into high purity gypsum by-product.

关键词： calcium molybdate molybdenum H2SO4 leaching HCl leaching thermodynamics

Precursor solution prepared by evaporation deamination complex method for solvent separation of Mo and W by H_2O_2-complexation

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Transactions of Nonferrous Metals Society of China 2013年第4期23卷 1139-1146页

作者：关文娟张贵清高从堦中南大学冶金科学与工程学院长沙410083 中南大学稀有金属冶金与材料制备湖南省重点试验室长沙410083

An novel method on preparation of precursor solution for solvent separation of molybdenum （Mo） and tungsten （W） by hydrogen peroxide （H2O2）-complexation from the ammonium tungstate solution containing high Mo was studied. The precursor solution was obtained via evaporation deamination and H202-complex transformation processes. Then it was extracted with a mixture extractant of tri-alkyl phosphine oxide （TRPO） and tributyl phosphate （TBP） to separate Mo and W. The results indicated that the evaporation deamination complex method reduced the acid consumption by more than 90% in comparison with the traditional directly acid regulation complex method. The transformation rates of W and Mo were higher than 95% and the decomposition rate of H202 was less than 15% at a 1.8-1.9 times H202 dosage, 45-50 ℃, initial pH of 1.80-1.90, and transformation volume ratio of 100% for 60 min in the H2O2-complexation transformation process. The minimum extraction rate of W was 2%, the maximum extraction rate of Mo was 82.6% and the highest separation coefficient was 76.7 in a single-stage extraction.

关键词： tungsten molybdenum solvent extraction separation precursor solution H202

采用TFCA-4PC协同萃取体系从废旧锂离子电池酸浸液中选择性萃取镍

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Transactions of Nonferrous Metals Society of China 2024年第4期34卷 1311-1320页

作者：张立涵曹佐英张贵清李青刚王明玉关文娟巫圣喜邓奇中南大学冶金与环境学院长沙410083 中南大学冶金分离科学与工程重点实验室长沙410083 湖南省林业科学院木本油料资源利用国家重点实验室长沙410018 湖南省林业科学院油脂分子构效湖南省重点实验室长沙410018

采用一种由桐油基羧酸(TFCA)与异烟酸酯(4PC)组成的协同溶剂萃取(SSX)体系,从含Mg/Li的废旧锂离子电池(LIBs)酸浸液中选择性萃取Ni。SSX体系对Ni表现出较强的协同作用,这主要归因于TFCA可以与Ni形成较为稳定的多元螯环结构,因此,体系对N... 详细信息

采用一种由桐油基羧酸(TFCA)与异烟酸酯(4PC)组成的协同溶剂萃取(SSX)体系,从含Mg/Li的废旧锂离子电池(LIBs)酸浸液中选择性萃取Ni。SSX体系对Ni表现出较强的协同作用,这主要归因于TFCA可以与Ni形成较为稳定的多元螯环结构,因此,体系对Ni的选择性得到增强。在优化条件下,经过单级萃取,Ni的萃取率达到97.3%,而Mg和Li的萃取率分别为0和2.29%。随后,负载有机相经过300mg/LNiSO_(4)洗涤后采用0.2 mol/L H_(2)SO_(4)反萃,获得的反萃液中含有11.52 g/L的Ni和<6 mg/L的Li。

关键词：桐油羧酸萃取剂协同溶剂萃取镍萃取机理

Primary parenchymal squamous cell carcinoma of the kidney:A case report

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World Journal of Clinical Cases 2025年第4期13卷 34-40页

作者： Zhi-Hui Zheng Bo Shao Chao-Min Xu Ke Wang Jia-Zhu wen Li-Kang Luo Jia-Cheng guan Department of Ultrasound The Second People’s Hospital of QuzhouQuzhou 324000Zhejiang ProvinceChina Department of Radiology Shulan(Quzhou)HospitalQuzhou 324000Zhejiang ProvinceChina Department of Radiology The Second People’s Hospital of QuzhouQuzhou 324000Zhejiang ProvinceChina Department of Pathology The Second people’s Hospital of QuzhouQuzhou 324000Zhejiang ProvinceChina

BACKGROUND Primary squamous cell carcinoma(SCC)of the renal parenchyma is extremely rare,with only nine cases *** SUMMARY This study reports a 51-year-old man with primary SCC of the renal *** patient was admitted with recurrent dull pain and discomfort in the right lumbar region,which had worsened over 2 weeks,accompanied by painful gross *** antigen(SCCA)levels were elevated,and imaging revealed a renal mass with associated *** patient underwent laparoscopic unilateral nephrectomy and lymph node *** pathology confirmed highly differentiated SCC with necrosis in the right renal parenchyma,with negative renal pelvis and *** pathological stage was *** months after surgery,the tumor recurred with involvement of the liver,right psoas major muscle,and inferior vena *** patient refused chemotherapy and succumbed to the disease 6 months postoperatively due to disease *** We report a case of primary SCC of the renal parenchyma,a rare renal *** clinical symptoms,laboratory tests,and imaging findings are nonspecific,making accurate and timely diagnosis *** to the literature,for patients with renal calculi accompanied by a renal mass,elevated serum SCCA levels,and magnetic resonance imaging showing cystic or cystic-solid masses within the kidney with pseudocapsules and heterogeneous mild enhancement,the possibility of this disease should be considered.

关键词： Renal tumor Renal parenchyma Squamous cell carcinoma Renal calculi Computed tomography Case report

消费者估值不确定下众筹定价策略及退款机制研究

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管理工程学报 2025年第1期39卷 256-270页

作者：徐扬毕功兵宋文吴娟安徽财经大学金融学院安徽蚌埠233030 中国科学技术大学管理学院安徽合肥230026 南京审计大学金融学院江苏南京211815

众筹作为最受欢迎的互联网金融产品之一,受到工业界和学术界的广泛关注。基于现实背景,本文建立了两阶段众筹模型,研究了消费者估值不确定下消费者的策略性选择行为及其对众筹定价策略的影响。结论表明,若消费者参与众筹的额外效用较低... 详细信息

众筹作为最受欢迎的互联网金融产品之一,受到工业界和学术界的广泛关注。基于现实背景,本文建立了两阶段众筹模型,研究了消费者估值不确定下消费者的策略性选择行为及其对众筹定价策略的影响。结论表明,若消费者参与众筹的额外效用较低,消费者估值不确定会造成“搭便车”现象,导致最优众筹价格不是关于项目所需资金的单增函数。当项目所需资金较低或较高时,发起人应该设置较高的众筹价格,否则应该降低价格以激励更多的消费者参与众筹。通过对比传统销售模式,本文揭示了发起人可以利用消费者估值不确定性及众筹的预售机制增加销量或边际收益以提升利润。进一步,本文证明了退款机制可以有效增加消费者参与众筹的意愿,从而提高众筹的可行域。最后,本文将基本模型拓展到更加一般的情形,研究发现众筹市场大小、项目运作风险和生产能力均对最优定价决策有不可忽视的影响。

关键词：众筹定价决策估值不确定策略型消费者退款机制

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基于隐性句逗号识别的汉语长句机器翻译

外语学刊 2025年第1期 39-46页

作者：冯文贺李熳佳张文娟广东外语外贸大学外国语言学及应用语言学研究中心语言工程与计算实验室广州510420 广州理工学院计算机科学与工程学院广州510420

长句翻译一直是机器翻译的难题。本文根据汉语中相当数量的逗号和句号可相互转化的特点,提出“隐性句号”和“隐性逗号”概念,并实现其自动识别,以将汉语长句变为短句用于汉英机器翻译。为此,首先通过人工与半监督学习结合方法构建一个... 详细信息

长句翻译一直是机器翻译的难题。本文根据汉语中相当数量的逗号和句号可相互转化的特点,提出“隐性句号”和“隐性逗号”概念,并实现其自动识别,以将汉语长句变为短句用于汉英机器翻译。为此,首先通过人工与半监督学习结合方法构建一个隐性句逗数据集,实现基于预训练模型的隐性句逗识别方法,其中性能最好的Hierarchical BERT作为后续应用模型。进而,实现基于隐性句逗识别的汉英机器翻译方法。在新闻和文学公开翻译测试语料上基于预训练机器翻译模型的实验表明,对于汉语长句的英译,本文方法相比基准翻译的BLEU值整体有所提高,而且在相对稳健机器翻译模型上,呈现为句子越长本文方法效果越明显。

关键词：机器翻译长句翻译隐性句逗号汉语长句逗号识别句内标点

Analysis and simulation of the tune ripple effect on beam spill ripple in RF-KO slow extraction

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Nuclear Science and Techniques 2022年第5期33卷 91-101页

作者： wen-Bo Ye Hong-juan Yao Shu-Xin Zheng Xia-Ling guan Xue-Wu Wang Key Laboratory of Particle and Radiation Imaging(Tsinghua University) Ministry of EducationBeijing 100084China Laboratory for Advanced Radiation Sources and Application Tsinghua UniversityBeijing 100084China Department of Engineering Physics Tsinghua UniversityBeijing 100084China

Tune ripple has a significant influence on beam spill ripple in RF-knockout(RF-KO)slow *** this study,a model was proposed to explain how the tune ripple affects the beam spill in RF-KO slow extraction;consequently,a simulation was performed using the lattice of the Xi’an Proton Application Facility(XiPAF)synchrotron to verify the *** simulation demonstrates that the tune ripple influences the beam spill in two *** the one hand,the tune ripple causes a direct fluctuation in the separatrix area,which induces beam spill *** the other hand,the tune ripple influences the emittance growth rate in RF-knockout slow *** two aspects simultaneously contribute to the beam spill ripple.

关键词： RF-knockout slow extraction Synchrotron Tune ripple Power supply ripple Beam spillripple

A neurovascular unit-on-a-chip:culture and differentiation of human neural stem cells in a three-dimensional microfluidic environment

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Neural Regeneration Research 2022年第10期17卷 2260-2266页

作者： wen-juan Wei Ya-Chen Wang Xin guan Wei-Gong Chen Jing Liu Stem Cell Clinical Research Center National Joint Engineering LaboratoryRegenerative Medicine Centerthe First Affiliated Hospital of Dalian Medical UniversityDalianLiaoning ProvinceChina Dalian Innovation Institute of Stem Cell and Precision Medicine DalianLiaoning ProvinceChina

Biological studies typically rely on a simple monolayer cell culture,which does not reflect the complex functional characteristics of human tissues and organs,or their real response to external *** technology has advantages of high-throughput screening,accurate control of the fluid velocity,low cell consumption,long-term culture,and high *** combining the multipotential differentiation of neural stem cells with high throughput and the integrated characteristics of microfluidic technology,an in vitro model of a functionalized neurovascular unit was established using human neural stem cell-derived neurons,astrocytes,oligodendrocytes,and a functional microvascular *** model comprises a multi-layer vertical neural module and vascular module,both of which were connected with a syringe *** provides controllable conditions for cell inoculation and nutrient supply,and simultaneously simulates the process of ischemic/hypoxic injury and the process of inflammatory factors in the circulatory system passing through the blood-brain barrier and then acting on the nerve tissue in the *** in vitro functionalized neurovascular unit model will be conducive to central nervous system disease research,drug screening,and new drug development.

关键词： (neural)differentiation astrocyte blood-brain barrier brain microvascular endothelial cells central nervous system microfluidics neural stem cells neuron neurovascular unit oligodendrocyte organ-on-a-chip

Polaron, molecule and pairing in one-dimensional spin-l/2 Fermi gas with an attractive Delta-function interaction

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Frontiers of physics 2012年第1期7卷 8-15页

作者： Xi-wen guan Department of Theoretical Physics Research School of Physics and Engineering Australian National University Canberra Australia

Using solutions of the discrete Bethe ansatz equations, we study in detail the quantum impurity problem of a spin-down fermion immersed into a fully ploarized spin-up Fermi sea with weak attrac- tion. We prove that this impurity fermion in the one-dimensional （1D） fermionic medium behaves like a polaron for weak attraction. However, as the attraction grows, the spin-down fermion binds with one spin-up fermion from the fully-polarized medium to form a tightly bound molecule. Thus it is seen that the system undergos a crossover from a mean field polaron-like nature into a mixture of excess fermions and a bosonic molecule as the attraction changes from weak attraction into strong attraction. This polaron-molecule crossover is universal in 1D many-body systems of interacting fermions. In a thermodynamic limit, we further study the relationship between the Fredholm equa- tions for the 1D spin-l/2 Fermi gas with weakly repulsive and attractive delta-function interactions.

关键词： spin-1/2 Fermi gas polaron molecule Fredholm equations