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Effect of pyrite content on chalcopyrite flotation under different regrinding conditions

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 49-57页

作者： Zejun Wang qing Shi Guofan Zhang Yuxuan zhu Binbin Li School of Minerals Processing and Bioengineering Central South UniversityChangsha 410083China Key Laboratory of Hunan Province for Clean and Efficient Utilization of Strategic Calcium-containing Mineral Resources Central South UniversityChangsha 410083China

This study aimed to investigate the effect of varying pyrite(Py)content on copper(Cu)in the presence of different regrinding conditions,which were altered using different types of grinding media:iron,ceramic balls,and their mixture,followed by flotation in the cleaner *** flotation performance of rough Cu concentrate can be improved by changing the regrinding conditions based on the Py *** electron microscopy,X-ray spectrometry,ethylenediaminetetraacetic acid disodium salt extraction,and X-ray photoelectron spectroscopy studies illustrated that when the Py content was high,the use of iron media in regrinding promoted the generation of hydrophilic Fe OOH on the surface of Py and improved the Cu *** ceramic medium with a low Py content prevented excessive Fe OOH from covering the surface of chalcopyrite(Cpy).Electrochemical studies further showed that the galvanic corrosion current of Cpy-Py increased with the addition of Py and became stronger with the participation of iron media.

关键词： chalcopyrite regrinding media pyrite galvanic corrosion flotation

Characteristic changes in astrocyte properties during astrocyte-to-neuron conversion induced by NeuroD1/Ascl1/Dlx2

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Neural Regeneration Research 2025年第6期20卷 1801-1815页

作者： qing He Zhen Wang Yuchen Wang Mengjie zhu Zhile Liang Kanghong Zhang Yuge Xu Gong Chen GHM Institute of CNS Regeneration Jinan UniversityGuangzhouGuangdong ProvinceChina

Direct in vivo conversion of astrocytes into functional new neurons induced by neural transcription factors has been recognized as a potential new therapeutic intervention for neural injury and degenerative disorders. However, a few recent studies have claimed that neural transcription factors cannot convert astrocytes into neurons, attributing the converted neurons to pre-existing neurons mis-expressing transgenes. In this study, we overexpressed three distinct neural transcription factors––NeuroD1, Ascl1, and Dlx2––in reactive astrocytes in mouse cortices subjected to stab injury, resulting in a series of significant changes in astrocyte properties. Initially, the three neural transcription factors were exclusively expressed in the nuclei of astrocytes. Over time, however, these astrocytes gradually adopted neuronal morphology, and the neural transcription factors was gradually observed in the nuclei of neuron-like cells instead of astrocytes. Furthermore,we noted that transcription factor-infected astrocytes showed a progressive decrease in the expression of astrocytic markers AQP4(astrocyte endfeet signal), CX43(gap junction signal), and S100β. Importantly, none of these changes could be attributed to transgene leakage into preexisting neurons. Therefore, our findings suggest that neural transcription factors such as NeuroD1, Ascl1, and Dlx2 can effectively convert reactive astrocytes into neurons in the adult mammalian brain.

关键词： aquaporin-4 Ascl1 astrocyte cortex Dlx2 gap junction glia-to-neuron conversion neural regeneration NeuroD1 reprogramming

Trinuclear gold-catalyzed site-selective alkylation of peptides

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Science China Chemistry 2025年第1期 249-256页

作者： qing-Yun Fang Chengyihan Gu Yinghan Chen Wencheng Yan Yong Liang Weipeng Li Chengjian zhu Jie Han Jin Xie State Key Laboratory of Coordination Chemistry Jiangsu Key Laboratory of Advanced Organic Materials Chemistry and Biomedicine Innovation Center (Chem BIC) School of Chemistry and Chemical Engineering Nanjing University Green Catalysis Center College of Chemistry Zhengzhou University State Key Laboratory of Natural Medicines China Pharmaceutical University

Selective modification of peptides has always been a challenging issue. The selective alkylation of peptides can alter the biological activity and physical properties of molecules, and it has gained significant research interest. We herein disclose an intriguing gold-catalyzed alkylation of peptides using bench-stable unactivated alkyl bromides under photoredox catalysis. A wide range of structurally diverse primary, secondary and tertiary alkyl bromides serve as effective coupling partners to precisely connect with the α-C(sp3)–H in glycine residue of peptides. This protocol demonstrates an exceptionally broad scope for alkyl halides and excellent tolerance for a wide range of useful functional groups. A series of relay transformations to construct cyclic peptides, to proceed click reaction and to realize peptide fluorescence labeling further enhance its synthetic practicality. In addition, mechanistic studies and density functional theory(DFT) calculations reveal an inner-sphere and subsequent outersphere single electron transfer(SET) mechanism.

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Tuning the porosity of {Co12IICo8III（μ3-OH）24（X）}11+ supramolecular frameworks by reaction time for D2/H2 separation

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Science China Chemistry 2025年

作者： zhuozhou Xie zhu zhuo Zi-Ang Nan qing Li Xiufang Li Zi-Xiu Lu Linzhe Lü Jin Liu Luyao Liu Wenjing Wang Wei Wang Daqiang Yuan You-Gui Huang State Key Laboratory of Structure Chemistry Fujian Institute of Research on the Structure of Matter Chinese Academy of Sciences University of Chinese Academy of Sciences Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth Materials Haixi InstitutesChinese Academy of Sciences State Key Laboratory of Physical Chemistry of Solid Surfaces Department of Chemistry College of Chemistry and Chemical EngineeringXiamen University

Systematicly tuning the porosities of porous materials is crucial for targeted gas mixture separation,yet it remains a longstanding *** a common strategy,altering the phenylene ring count in the organic building units has been exploited to adjust pore apertures in metal organic frameworks （MOFs） and covalent organic frameworks （COFs）,resulting in only a stepwise pore size variation of approximately 2.8?.Unlike MOFs and COFs,the porosities for supramolecular assembly frameworks are highly dependent on the packings of the molecular building units in the *** above strategy cannot be applied to supramolecular assembly frameworks and other strategies are required to adjust pore apertures in supramolecular frameworks,especially to achieve porous materials with the optimal pore size for D2/H2separation （～3?）.Here,we successfully modulate the porosity of supramolecular frameworks of[CoII1+12CoIII8L12（μ3-OH）24（X）]1clusters （L=mono-deprotonated 1-iminoisoindole-3-amine,X=ClO?4or Cl?） by controlling the duration of self-assembly *** simply adjusting the reaction time,we obtain three[CoII12CoIII8L12（μ3-OH）24（X）]11+supramolecular frameworks:[CoII12CoIII8（μ3-OH）24（ClO4）L12)]·（Cl）4·（HCO2）7（1）,[CoII12CoIII8L12（μ3-OH）24（Cl）]·（ClOI4）4·（Cl）6·（HCO2）·（H2O）10（2）,and[CoI12CoIII8L12（μ3-OH）24（Cl）]·（Cl）11·（H2O）12（3）.The different stacking patterns of the[CoII12CoIII8L12（μ3-OH）24（X）]11+clusters in these frameworks lead to significantly varied stabilities and *** 1 exhibits permanent porosity with interconnected channels and maintains stability under harsh *** contrast,compound 2 is nearly nonporous,and compound 3 becomes unstable upon *** pores of compound 1 show higher affinity to D2than H2,and the pore aperture diameter of compound 1 （～3.06?） meets the optimal porosity for D2/***,compound 1 demonstrates moderate D2/H2separation at 77 K (retention time:～7 min/g for D2/H2/Ne （10/10/80 vol%） in a flow of 5 mL

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Smooth support vector machine based on piecewise function

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The Journal of China Universities of Posts and Telecommunications 2013年第5期20卷 122-128页

作者： WU qing FAN Jiu-lun School of Automation Xi'an University of Posts and Telecommunications School of telecommunication and information engineering Xi'an University of Posts and Telecommunications

Support vector machines （SVMs） have shown remarkable success in many applications. However, the non-smooth feature of objective function is a limitation in practical application of SVMs. To overcome this disadvantage, a twice continuously differentiable piecewise-smooth function is constructed to smooth the objective function of unconstrained support vector machine （SVM）, and it issues a piecewise-smooth support vector machine （PWESSVM）. Comparing to the other smooth approximation functions, the smooth precision has an obvious improvement. The theoretical analysis shows PWESSVM is globally convergent. Numerical results and comparisons demonstrate the classification performance of our algorithm is better than other competitive baselines.

关键词： SVM smooth technique piecewise function bound of convergence

Strategies for improving the efflcacy of immunotherapy in hepatocellular carcinoma

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Hepatobiliary & Pancreatic Diseases International 2022年第5期21卷 420-429页

作者： Ying zhu lun-Xiu Qin Department of General Surgery Huashan HospitalCancer Metastasis InstituteFudan UniversityShanghai 200040China Institutes of Biomedical Sciences Fudan UniversityShanghai 200032China

Primary liver cancer,mainly hepatocellular carcinoma(HCC),is the sixth most diagnosed cancer and third leading cause of cancer-related death ***,immunotherapies such as immune checkpoint inhibitors(ICIs)have made great progress in the systemic treatment of ***,anti-PD-1 therapy with pembrolizumab or nivolumab as a single agent did not meet their predefined end points of overall survival in the KEYNOTE-240 and Check Mate 459 *** is urgent to understand the immunological rationale and explore novel ways to improve the efflcacy of *** combination of ICIs with other therapies,such as tyrosine kinase inhibitors(TKIs),monoclonal antibodies,or local therapy,has been demonstrated to improve overall response rate and *** addition,modulating tumor microenvironment is a potential way to overcome the primary and secondary resistance to *** this review,we summarized the latest findings in the immune microenvironment,the mechanisms of their synergistic effects when combined with anti-VEGF agents or TKIs,as well as other kinds of immune treatment.

关键词： Hepatocellular carcinoma Tumor microenvironment Immune checkpoint inhibitors Interferon-α Programmed death receptor 1

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城市发展管控区村庄居民点布局模式探索

华中建筑 2025年第1期43卷 130-134页

作者：侯青顾哲章伦浙江精创建设工程施工图审查中心浙江大学城市规划与设计研究所龙港市自然资源与规划建设局

该文从空间、社会、经济、文化等角度综合分析了当前农村居民点规划布局,多要素综合研究相关布局模式在城市发展管控区的适用性,指出相关布局模式在社会网络关系保持、乡村地方文化延续、发展可持续性等方面的缺失与不足。结合以上研究... 详细信息

该文从空间、社会、经济、文化等角度综合分析了当前农村居民点规划布局,多要素综合研究相关布局模式在城市发展管控区的适用性,指出相关布局模式在社会网络关系保持、乡村地方文化延续、发展可持续性等方面的缺失与不足。结合以上研究,提出了基于地域性的有机集聚布局模式,并在相关案例中分析应用,为该类区域的乡村发展和城市发展管控提供思路,也为相关地域的国土空间规划和乡村规划提供参考。

关键词：城市发展管控区村庄居民点布局模式地域性有机集聚

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Complex Behavior in a Selective Aging Neuron Model Based on Small World Networks

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Communications in Theoretical Physics 2008年第2期49卷 409-413页

作者： ZHANG Gui-qing CHEN Tian-lun Department of Physics Nankai University Tianjin 300071 China

Complex behavior in a selective aging simple neuron model based on small world networks is investigated. The basic elements of the model are endowed with the main features of a neuron function. The structure of the selective aging neuron model is discussed. We also give some properties of the new network and find that the neuron model displays a power-law behavior. If the brain network is small world-like network, the mean avalanche size is almost the same unless the aging parameter is big enough.

关键词： selective aging self-organized criticality small world networks finite-size-scaling analysis power-law

BIVARIATE LAGRANGE-TYPE VECTOR VALUED RATIONAL INTERPOLANTS

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Journal of Computational Mathematics 2002年第2期20卷 207-216页

作者： Chuan-qing Gu Gong-qing zhu Department of Mathematics Shanghai UniversityShanghai 200436China Department of Mathematics Hefei Polytechnic UniversityHefei 230009China

Focuses on a study that presented an axiomatic definition to bivariate vector valued rational interpolation on distinct plane interpolation points. Definition; Existence and uniqueness; Connection.

关键词： bivariate vector value rational interpolation determinantal formula