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废旧锂离子电池放电方案的试验分析

厦门理工学院学报 2024年第3期32卷 88-95页

作者：林彩凤刘翔宇王越王振鹏程前厦门理工学院环境科学与工程学院福建厦门361024

以废旧手机锂离子电池为研究对象,分析不同放电方案下废旧锂离子电池的放电效果,并对最佳放电溶液中Li、Co等金属离子的含量以及滤渣成分进行表征。研究表明,当NaCl质量浓度为10%时,放电1 h放电率约54%;石墨掩埋和铜粉掩埋2.7 h最高放... 详细信息

以废旧手机锂离子电池为研究对象,分析不同放电方案下废旧锂离子电池的放电效果,并对最佳放电溶液中Li、Co等金属离子的含量以及滤渣成分进行表征。研究表明,当NaCl质量浓度为10%时,放电1 h放电率约54%;石墨掩埋和铜粉掩埋2.7 h最高放电率分别为35.96%和12.34%,且存在电压反弹现象,石墨粉和NaCl溶液混合可增强放电效果。最佳放电方案为,在120 r·min^(-1)搅拌的条件下,将废旧锂离子电池浸泡在10%NaCl溶液与40 g·L^(-1)80目石墨粉的混合溶液中,放电80 min,放电率为81.87%。过滤放电溶液并用ICP-OES分析滤液,结果表明,滤液含Li、Co离子,且Li、Co离子质量浓度随放电时间的延长而增加,放电80 min后,Li、Co的离子质量浓度分别为0.128、0.01 g·L^(-1),之后变化缓慢;用FT-IR表征烘干后的滤渣,其主要成分为石墨,未检测到有机物杂质;Li、Co离子质量浓度以及石墨粉成分的变化为放电溶液的重复利用并从中回收有价金属提供参考。

关键词：废旧锂离子电池放电方案放电率化学放电法物理放电法石墨粉和NaCl溶液混合介质

Co-NC as adsorbent and matrix providing the ability of MALDI MS to analyze volatile compounds

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Chinese Chemical Letters 2021年第1期32卷 62-65页

作者： Shumu Li Jian’an Liu Jiping Sun zhenpeng wang Kai wang Lei Guo Shuliang Yang Jinchao Wei Xiangjun Zheng Zhenwen Zhao Beijing National Laboratory for Molecular Sciences CAS Research/Education Center for Excellence in Molecular SciencesKey Laboratory of Analytical Chemistry for Living BiosystemsInstitute of ChemistryChinese Academy of SciencesBeijing Mass Spectrum CenterBeijing 100190China Graduate School University of Chinese Academy of SciencesBeijing 100049China Beijing Key Laboratory of Energy Conversion and Storage Materials College of ChemistryBeijing Normal UniversityBeijing 100875China State Key Laboratory of Toxicology and Medical Countermeasures and Laboratory of Toxicant AnalysisAcademy of Military Medical SciencesBeijing 100850China

Traditional matrix does not allow matrix-assisted laser desorption/ionization mass spectrometry(MALDI MS) to analyze volatile compounds,because volatile analytes may vaporize during the sample preparation process or in the high vacuum circumstance of ion ***,we reported a Co and N doped porous carbon material(Co-NC) which were synthesized by pyrolysis of a Schiff base coordination ***-NC could simultaneously act as adsorbent of volatile compounds and as matrix of MALDI MS,to provide the capability of MALDI MS to analyze volatile *** adsorbent,Co-NC could stro ngly adsorb and enrich the volatile compounds in perfume and herbs,and hold them even in the high vacuum *** the other hand,Co-NC could absorb the energy of the laser,and then transfer the energy to the analyte for desorption and ionization of analyte in both negative and positive ionization ***,the background interferences were avoided in the low-mass region(<500 Da) when using Co-NC as matrix,overcoming the challenges of MALDI MS analysis of small molecule *** summary,Co-NC as matrix tremendously extended the application of MALDI MS.

关键词： MALDI MS Volatile compounds Matrix Co-NC Adsorbent

The Structure Entropy of Social Networks

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Journal of Systems Science & Complexity 2024年第3期37卷 1147-1162页

作者： LI zhenpeng YAN Zhihua YANG Jian TANG Xijin School of Electronics and Information Engineering Taizhou UniversityLinhai 317000China Academy of Mathematics and Systems Science Chinese Academy of SciencesBeijing 100190China Yunnan Key Laboratory of Smart City in Cyberspace Security Yuxi Normal UniversityYuci 653100China University of Chinese Academy of Sciences Beijing 100039China

Micro triadic structure is an important motif and serves the building block of complex *** this paper,the authors define structure entropy for a social network and explain this concept by using the coded triads proposed by Davis and Leinhardt in *** proposed structure entropy serves as a new macro-evolution index to measure the network’s stability at a given *** analysis of real-world network structure entropy discloses rich information on the mechanism that yields given triadic motifs frequency *** paper illustrates the intrinsic link between the micro dyadic/triadic motifs and network structure ***,the authors find that the high proportion of reciprocity and transitivity results in the emergence of hierarchy,order,and cooperation of online social networks.

关键词： Dyadic and triadic motifs network structure entropy reciprocity and transitivity

Stereoselective Synthesis of 2-Deoxy-α-N-Glycosides from Glycals with 1,4,2-Dioxazol-5-ones

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Chinese Journal of Chemistry 2024年第18期42卷 2147-2152页

作者： zhenpeng Shen Guoyin Yin Yangyang Li The Institute for Advanced Studies Wuhan UniversityWuhanHubei 430072China

The synthesis of N-glycosides has received significant attention due to their crucial role in carbohydrate *** considerable advancements developed in the construction of N-glycosides,methods for the stereoselective construction of 2-deoxy-α-N-glycosides are still ***,we disclosed a nickel-catalyzed hydroamination of glycals under mild *** transformation could allow for the stereoselective synthesis of an array of 2-deoxy-α-N-glycosides with excellentα-***-catalyzed glycosylation reactions,particularly those involving anomeric C(sp")-metal bond formation,have proven to be an effective and stereoselective strategy for producing various ***,with highlight of the application of this reaction,y-sugar amino acidderivatives weresynthesized.

关键词： 2-Deoxy-α-N-glycosides Nickel catalysis Stereoselectivity Glycals Hydroamination Amides Glycosylation Alkenes ComprehensiveSummary

Structure and immunomodulatory activity of Lentinus edodes polysaccharides modified by probiotic fermentation

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Food Science and Human Wellness 2024年第1期13卷 421-433页

作者： Jingjing Liang Meina Zhang Xiaohan Li Yuan Yue Xiaowei wang Mengzhen Han Tianli Yue Zhouli wang zhenpeng Gao College of Food Science and Engineering Northwest A&F UniversityYangling 712100China Xi'an GaoXin No.1 High School Xi'an 710065China

Plant-based fermentations provide an untapped source for novel biotechnological *** this study,a probiotic named Lactobacillus fermentum 21828 was introduced to ferment Lentinus *** were extracted from fermented and non-fermented *** and purified via DEAE-52 and Sephadex *** components designated F-LEP-2a and NF-LEP-2a were analyzed by FT-IR,HPGPC,HPAEC,SEM,GC-MS and *** results revealed that probiotic fermentation increased the molecular weight from 1.16×10^(4) Da to 1.87×10^(4) Da and altered the proportions of glucose,galactose and mannose,in which glucose increased from 45.94%to 48.16%.Methylation analysis and NMR spectra indicated that F-LEP-2a and NF-LEP-2a had similar linkage ***,their immunomodulatory activities were evaluated with immunosuppressive ***-LEP and F-LEP improved immune organ indices,immunoglobulin(Ig G and Ig M)and cytokines concentrations;restored the antioxidation capacity of liver;and maintained the balance of gut microbiota.F-LEP displayed better moderating effects on the spleen index,immunoglobulin,cytokines and the diversity of gut microbiota than NF-LEP(200,400 mg/kg).Our study provides an efficient and environment-friendly way for the structural modification of polysaccharides,which helps to enhance their biological activity and promote their wide application in food,medicine and other fields.

关键词： Lentinus edodes polysaccharide Lactobacillus fermentum fermentation Structural analysis Immunoregulatory activity Nuclear magnetic resonance

Maslinic acid supplementation prevents di(2-ethylhexyl)phthalate-induced apoptosis via PRDX6 in peritubular myoid cells of Chinese forest musk deer

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Journal of Environmental Sciences 2024年第9期143卷 47-59页

作者： Heran Cao zhenpeng Li Tianqi Jin Shuyang He Shujuan Liu Long Li Yang wang Ye Gong Gang wang Fangxia Yang Wuzi Dong College of Animal Science and Technology Northwest A&F UniversityShaanxi 712100China College of Forestry Northwest A&F UniversityShaanxi 712100China Biology Research Centre of Qin-Mountains Wildlife Northwest A&F UniversityShaanxi 712100China Shaanxi Qiyuan-Times Agri-Tech Development Co.Ltd. Shaanxi 725000China

Chinese forest musk deer(FMD),an endangered species,have exhibited low reproductive rates even in captivity due to stress *** revealed the presence of di(2-ethylhexyl)phthalate(DEHP),an environmental endocrine disruptor,in the serum and skin of captive *** FMDs with maslinic acid(MA)has been observed to alleviate the stress response and improve reproductive rates,although the precise molecular mechanisms remain ***,this study aims to investigate the molecular mechanisms underlying the alleviation of DEHP-induced oxidative stress and cell apoptosis in primary peritubular myoid cells(PMCs)through MA *** PMCs were isolated and exposed to DEHP in *** results demonstrated that DEHP significantly suppressed antioxidant levels and promoted cell apoptosis in primary ***,interfering with the expression of PRDX6 was found to induce excessive reactive oxygen species(ROS)production and cell apoptosis in primary *** with MA significantly upregulated the expression of PRDX6,thereby attenuating DEHP-induced oxidative stress and cell apoptosis in primary *** findings provide a theoretical foundation for mitigating stress levels and enhancing reproductive capacity of in captive FMDs.

关键词： Maslinic acid Forest musk deer Di(2-ethylhexyl)phthalate Peritubular myoid cells PRDX6

Conductive catalysis by subsurface transition metals

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National Science Review 2024年第1期11卷 86-93页

作者： Xin Deng Caiyan Zheng Yangsheng Li Zeyu Zhou Jiamin wang Yihua Ran zhenpeng Hu Fan Yang Landong Li Frontiers Science Center for New Organic Matter College of ChemistryNankai University School of Physics Nankai University School of Physical Science and Technology Shanghai Tech University School of Materials Science and Engineering Nankai University Haihe Laboratory of Sustainable Chemical Transformations

The nature of catalysis has been hotly pursued for over a century, and current research is focused on understanding active centers and their electronic structures. Herein, the concept of conductive catalysis is proposed and verified by theoretical simulations and experimental observations. Metallic systems containing buried catalytically active transitional metals and exposed catalytically inert main group metals are constructed, and the electronic interaction between them via metallic bonding is disclosed. Through the electronic interaction, the catalytic properties of subsurface transitional metals(Pd or Rh) can be transferred to outermost main group metals(Al or Mg) for several important transformations like semi-hydrogenation,Suzuki-coupling and hydroformylation. The catalytic force is conductive, in analogy with the magnetic force and electrostatic force. The traditional definition of active centers is challenged by the concept of conductive catalysis and the electronic nature of catalysis is more easily understood. It might provide new opportunities for shielding traditional active centers against poisoning or leaching and allow for precise regulation of their catalytic properties by the conductive layer.

关键词： electronic interaction conductive catalysis subsurface transition metal

What can we learn from quality assurance badges in open-source software?

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Science China(Information Sciences) 2024年第4期67卷 146-163页

作者： Feng LI Yiling LOU Xin TAN zhenpeng CHEN Jinhao DONG Yang LI Xuanzhi wang Dan HAO Lu ZHANG MoE Key Lab of HCST School of Computer SciencePeking University Department of Computer Science Purdue University School of Computer Science & Engineering Beihang University(BUAA) Department of Computer Science University College London(UCL)

In the development of open-source software(OSS), many developers use badges to give an overview of the software and share some key features/metrics conveniently. Among various badges, quality assurance(QA) badges make up a large proportion and are the most prevalent because QA is of vital importance in software development, and ineffective QA may lead to anomalies or defects. In this paper, we focus on QA badges in open-source projects, which present quality assurance information directly and instantly,and aim to produce some interesting findings and provide practical implications. We collect and analyze 100000 projects written in popular programming languages from GitHub and conduct a comprehensive empirical study both inside and outside QA badges. Inside QA badges, we build a category classification for all QA badges based on the properties they focus on, which shows the types of QA badges developers use. Then,we analyze the frequency of the properties that QA badges focus on, and property combinations, too, which present their use status. We find that QA badges focus on various properties while developers give different preferences to different properties. The use status also differs between different programming languages. For example, projects written in C focus on Security to a great extent. Our findings also provide implications for developers and badge providers. Outside QA badges, we conduct a correlation analysis between QA badges and some software metrics that have potential relationships with code quality, contribution quality, and popularity. We find that QA badges have statistically significant correlations with various software metrics.

关键词： quality assurance badge open-source software code quality empirical study

Subsurface deformation mechanism and the interplay relationship between strength–ductility and fretting wear resistance during fretting of a high-strength titanium alloy

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Friction 2024年第10期12卷 2259-2280页

作者： Yanlin TONG Ke HUA Haoyang XIE Yue CAO Zhuobin HUANG zhenpeng LIANG Xiaolin LI Hongxing WU Haifeng wang State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsNorthwestern Polytechnical UniversityXi’an 710072China

Fretting wear damage of high-strength titanium fasteners has caused a large number of disastrous ***,it is believed that both high strength and excellent ductility can reduce fretting wear ***,whether strength and ductility are contradictory or not and their appropriate matching strategy under the external applied normal stress(Fw)are still confusing ***,by analyzing the subsurface-microstructure deformation mechanism of several samples containing variousαprecipitate features,for the first time,we design strategies to improve fretting damage resistance under different matching relation between Fw and the tensile strength of materials(Rm).It is found that when Fw is greater than Rm or Fw is nearly equivalent to Rm,the deformation mechanism mainly manifests as serious grain fragmentation ofβandαGB *** deformation in large areas only reduces damage to a limited *** is crucial to improve the strength to resist cracking and wear,but it is of little significance to improve the ***,when Fw is far less than Rm,coordinated deformation ability reflected by ductility plays a more important *** deformation mechanism mainly manifests as localized deformation ofβandαGB constituents(kinking induced by twinning and spheroidizing).A unique composite structure of nano-grained/lamellar layer and localized deformation transition layer reduces fretting damage by five times compared with a single nanograined *** when the strength is great enough,improving the plasticity can reduce *** study can provide a principle for designing fretting damage resistant alloys.

关键词： fretting wear high-strength titanium alloy microstructures subsurface deformation