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Chinese Journal of Chemistry 2024年第10期42卷 1100-1106页

作者： Weidong ling Fei Wu Wentao Yuan linna Zhu Qianqian li zhen li Hubei Key Lab on Organic and Polymeric Opto-Electronic Materials Department of ChemistryWuhan UniversityWuhanHubei 430072China Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energy Faculty of Materials&EnergySouthwest UniversityChongqing400715China TaiKang Center for life and Medical Sciences Wuhan UniversityWuhanHubei 430072China

Perovskite solar cells(PSCs)have been proven to be a promising option for photovoltaic *** the aim to achieve efficient and stable PSCs,it is essential to explore dopant-free hole-transporting materials(HTMs)with high hole ***,HTMs bearing electron donor(D)-electron acceptor(A)-electron donor(D)structures have been constructed with strong intramolecular charge transfer(ICT)effect,based on rational combination of dibenzo[a,c]phenazine and pyridine as electronic acceptors and anchoring groups to perovskite ***,high hole mobility(7.31×10^(-5) cm^(2)·V^(-1)·s^(-1))and photoelectric conversion efficiency(20.45%)have been achieved by dopant-free DPyP-based *** afforded an efficient way to design HTMs with high hole mobility by adjustment of molecular configurations and electronic property of conjugated systems.

关键词： Perovskite solar cell Charge transfer Donor-acceptor systems Energy conversion Hole mobility

A scalable one-pot strategy for the development of polymer electrolytes adaptable to room-temperature high-voltage lithium batteries

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Chinese Chemical Letters 2024年第3期35卷 461-467页

作者： Yue Guo Xinxin Qu zhen li Ruiyuan Tian Xiaokong liu State Key Laboratory of Supramolecular Structure and Materials College of ChemistryJilin UniversityChangchun 130012China Key Laboratory of Physics and Technology for Advanced Batteries(Ministry of Education) College of PhysicsJilin UniversityChangchun 130012China

Poly(ethylene oxide)(PEO)polymer electrolytes(PEs)have been commercially applied in liFePO_(4)||li solid-state lithium batteries(SSLBs).However,it remains challenging to develop PEO-based PEs applicable to the high-voltage SSLBs with higher energy density,owing to the poor electrochemical stability of ***,we report a scalable strategy for fabricating PEO-based PEs with high-voltage compatibility,by exploiting a new mechanism to stabilize the cathode-electrolyte interface in the highvoltage *** protocol only involves a one-pot synthesis procedure to covalently crosslink the PEO chains,in the presence of high-content lithium bis(trifluoromethylsulphonyl)imide(liTFSI)salts and N,N-dimethylformamide(DMF).liTFSI-DMF supramolecular aggregates are formed and firmly embedded in the polymer network,endowing the PE with high room-temperature ionic *** dissociated and highly concentrated TFSI^-anions can enter the Helmholtz layer close to the high-voltage cathode,leading to the formation of a thin and homogeneous cathode electrolyte interface(CEI),mainly composed of liF,on the *** CEI with high electrochemical stability can effectively stabilize the cathode-electrolyte interface,enabling long-term stable cycling of the high-voltage liCoO_(2)||li and nickelrich NCM_(622)||li batteries at room *** simplicity and scalability of the strategy makes the reported PEO-based PE potentially applicable in high-voltage SSLBs in practice.

关键词： lithium batteries Polymer electrolytes Poly(ethylene oxide) Energy density High-voltage cathodes

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Enhancing flotation recovery of residual carbon from gasification waste by mixing hydrophobic powder with diesel as collector

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Particuology 2024年第6期89卷 211-217页

作者： Rui Han Ningning Zhang Anning Zhou zhen li Jinzhou Qu Hong Wang College of Chemistry and Chemical Engineering Xi’an University of Science and TechnologyXi’anShaanxi 710054China

Coal gasification fine slag(CGFS)is a solid waste containing residual carbon and ash generated during the coal gasification process,and the separation of the two components is the essential way to realize its environmental pollution reduction and resource value *** flotation is the preferred method for separating CGFS,but there is a barrier of low carbon recovery in this process due to the extensive adsorption of collector by the well-developed pores on residual *** this study,a sufficiently simple yet innovative collector,a mixture of hydrophobic powder and diesel,was proposed in an attempt to break the *** experiments with common diesel and this novel collector were performed respectively,and FTIR,XPS,and SEM-EDX were employed to analyze the collector action *** results revealed that the novel collector could significantly improve the residual carbon recovery;test results demonstrated that the novel collector could increase the hydrophobic functional group content on the fine slag surface,and the hydrophobic powders in this novel collector mainly appeared at the pore openings of the flotation *** essence of the mechanism is that the hydrophobic powders play a dual role of blocking pores and providing adsorption sites,thus facilitating the spreading of diesel on the carbon surface and promoting its *** study can provide creative ideas for the efficient disposal of coal gasification waste.

关键词： Coal gasification fine slag Carbon recovery Collector Fotation Hydrophobic powder

Metabolomic-based analysis reveals bile acid-mediated ovarian failure induced by low temperature in zebrafish

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Zoological Research 2024年第4期45卷 791-804页

作者： Wen-Hao li Zhi-Qiang li Meng-Di Bu Jia-zhen li liang-Biao Chen Key Laboratory of Exploration and Utilization of Aquatic Genetic Resources Ministry of EducationCollege of Fisheries and Life SciencesShanghai Ocean UniversityShanghai 201306China Laboratory for Marine Biology and Biotechnology Qingdao National Laboratory for Marine Science and TechnologyQingdaoShandong 266237China International Research Center for Marine Biosciences Ministry of Science and TechnologyCollege of Fisheries and Life SciencesShanghai Ocean UniversityShanghai 201306China

As ectotherms, fish are highly sensitive to temperature fluctuations, which can profoundly impact their reproductive cycles. In this study, we investigated the fertility and histological characteristics of zebrafish(Danio rerio) ovaries exposed to a temperature gradient ranging from the thermopreferendum temperature of the species,27℃, to lower temperatures of 22℃, 20℃, and 13℃ over a period of two weeks. Comparative metabolomic(six biological replicates for each temperature) and transcriptomic(four biological replicates for each temperature) analyses were conducted under the four temperature conditions. Results indicated that lower temperatures inhibited oocyte development and differential metabolites were involved in steroid hormone production,antioxidant function, and lipid and protein *** reproductive hormones, increased proteolysis,and lipid degradation significantly impeded oocyte development and egg maturation. Notably, a significant increase in bile acid content was noted in the ovaries of the cold-treated fish, indicating that bile acids play a critical role in ovarian failure. Overall, these findings provide valuable insights into the mechanisms governing the reproductive response of fish to cold stress.

关键词： old stress Ovarian failure Metabolome Zebrafish

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Prevalence and risk factors of diabetes mellitus among elderly patients in the Lugu community

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World Journal of Diabetes 2024年第4期15卷 638-644页

作者： li-zhen Zhao Wei-Min li Ying Ma Lugu Community Health Service Center West Campus Beijing Chao-yang Hospital Affiliated to Capital Medical UniversityBeijing 100043China

BACKGROUND Age is a significant risk factor of diabetes mellitus(DM).With the develop of population aging,the incidence of DM remains *** the epidemiology of DM among elderly individuals in a certain area contributes to the DM interventions for the local elderly individuals with high risk of *** To explore the prevalence of DM among elderly individuals in the Lugu community and analyze the related risk factors to provide a valid scientific basis for the health management of elderly *** A total of 4816 elderly people who came to the community for physical examination were retrospectively *** prevalence of DM among the elderly was *** individuals were divided into a DM group and a non-DM group according to the diagnosis of DM to compare the differences in diastolic blood pressure(DBP)and systolic blood pressure(SBP),fasting blood glucose,body mass index(BMI),waist-to-hip ratio(WHR)and incidence of hypertension(HT),coronary heart disease(CHD),and chronic kidney disease(CKD).RESULTS DM was diagnosed in 32.70%of the 4816 elderly *** BMI of the DM group(25.16±3.35)was greater than that of the non-DM group(24.61±3.78).The WHR was 0.90±0.04 in the non-DM group and 0.90±0.03 in the DM group,with no significant *** left SBP and SBP in the DM group were 137.9 mmHg±11.92 mmHg and 69.95 mmHg±7.75 mmHg,respectively,while they were 126.6 mmHg±12.44 mmHg and 71.15 mmHg±12.55 mmHg,respectively,in the non-DM *** findings indicate higher SBP and lower DBP in DM patients than in those without *** the DM group,1274 patients were diagnosed with HT,accounting for 80.89%.Among the 3241 non-DM patients,1743(53.78%)were hypertensive and 1498(46.22%)were *** DM group had more cases of HT than did the non-DM *** were more patients with CHD or CKD in the DM group than in the non-DM *** were more patients who drank alcohol more frequently(≥3 times)in the DM group than in the no

关键词： Diabetes mellitus Type 2 diabetes mellitus Elderly Risk factors

Sequential reactant water management by complementary multisite catalysts for surpassing platinum hydrogen evolution activity

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Nano Research 2024年第3期17卷 1232-1241页

作者： Yu lin Defang Ding Shicheng Zhu Qunlei Wen Huangjingwei li zhen li Youwen liu Yi Shen China Engineering Research Center of Nano-Geomaterials of Ministry of Education Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan 430078China State Key Laboratory of Materials Processing and Die&Mould Technology and School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Alkaline hydrogen evolution reaction(HER)offers a near-zero-emission approach to advance hydrogen ***,the activity limited by the multiple reaction steps involving H_(2)O molecules transfer,absorption,and activation still unqualified the thresholds of economic ***,we proposed a multisite complementary strategy that incorporates hydrophilic Mo and electrophilic V into Ni-based catalysts to divide the distinct steps on atomically dispersive sites and thus realize sequential regulation of the HER *** Isotopic labeled in situ Raman spectroscopy describes 4-coordinated hydrogen bonded H_(2)O to be free H_(2)O passing the inner Helmholtz plane in the vicinity of the catalysts under the action of hydrophilic Mo ***,potential-dependent electrochemical impedance spectroscopy(EIS)reveals that electrophilic V sites with abundant 3d empty orbitals could activate the lone-pair electrons in the free H_(2)O molecules to produce more protic hydrogen,and dimerize into H_(2) at the Ni *** the sequential management of reactive H_(2)O molecules,NiMoV oxides multisite catalysts surpass Pt/C hydrogen evolution activity(49 mV@10 mA∙cm^(-2) over 140 h).Profoundly,this study provides a tangible model to deepen the comprehension of the catalyst–electrolyte interface and create efficient catalysts for diverse reactions.

关键词： hydrogen evolution activity complementary multisite catalysts sequential reactive water management interfacial water molecules

Research on Performance Optimization of Spark Distributed Computing Platform

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Computers, Materials & Continua 2024年第5期79卷 2833-2850页

作者： Qinlu He Fan Zhang Genqing Bian Weiqi Zhang zhen li School of Information and Control Engineering Xi’an University of Architecture and TechnologyXi’an710054China Shaanxi Institute of Metrology Science Xi’an710043China

Spark,a distributed computing platform,has rapidly developed in the field of big *** in-memory computing feature reduces disk read overhead and shortens data processing time,making it have broad application prospects in large-scale computing applications such as machine learning and image ***,the performance of the Spark platform still needs to be *** a large number of tasks are processed simultaneously,Spark’s cache replacementmechanismcannot identify high-value data partitions,resulting inmemory resources not being fully utilized and affecting the performance of the Spark *** address the problem that Spark’s default cache replacement algorithm cannot accurately evaluate high-value data partitions,firstly the weight influence factors of data partitions are modeled and ***,based on this weighted model,a cache replacement algorithm based on dynamic weighted data value is proposed,which takes into account hit rate and data *** integration and usage strategies are implemented based on LRU(LeastRecentlyUsed).Theweight update algorithm updates the weight value when the data partition information changes,accurately measuring the importance of the partition in the current job;the cache removal algorithm clears partitions without useful values in the cache to releasememory resources;the weight replacement algorithm combines partition weights and partition information to replace RDD partitions when memory remaining space is ***,by setting up a Spark cluster environment,the algorithm proposed in this paper is experimentally *** have shown that this algorithmcan effectively improve cache hit rate,enhance the performance of the platform,and reduce job execution time by 7.61%compared to existing improved algorithms.

关键词： Spark memory optimization memory replacement strategy

Identifying malicious traffic under concept drift based on intraclass consistency enhanced variational autoencoder

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Science China(Information Sciences) 2024年第8期67卷 238-252页

作者： Xiang LUO Chang liU Gaopeng GOU Gang XIONG zhen li Binxing FANG Institute of Information Engineering Chinese Academy of Sciences School of Cyber Security University of Chinese Academy of Sciences School of Computer Science and Technology Harbin Institute of Technology (Shenzhen)

Accurate identification of malicious traffic is crucial for implementing effective defense countermeasures and has led to extensive research efforts. However, the continuously evolving techniques employed by adversaries have introduced the issues of concept drift, which significantly affects the performance of existing methods. To tackle this challenge, some researchers have focused on improving the separability of malicious traffic representation and designing drift detectors to reduce the number of false ***, these methods often overlook the importance of enhancing the generalization and intraclass consistency in the representation. Additionally, the detectors are not sufficiently sensitive to the variations among different malicious traffic classes, which results in poor performance and limited robustness. In this paper, we propose intraclass consistency enhanced variational autoencoder with Class-Perception detector(ICE-CP) to identify malicious traffic under concept drift. It comprises two key modules during training:intraclass consistency enhanced(ICE) representation learning and Class-Perception(CP) detector construction. In the first module, we employ a variational autoencoder(VAE) in conjunction with Kullback-Leibler(KL)-divergence and cross-entropy loss to model the distribution of each input malicious traffic flow. This approach simultaneously enhances the generalization, interclass consistency, and intraclass differences in the learned representation. Consequently, we obtain a compact representation and a trained classifier for nondrifting malicious traffic. In the second module, we design the CP detector, which generates a centroid and threshold for each malicious traffic class separately based on the learned representation, depicting the boundaries between drifting and non-drifting malicious traffic. During testing, we utilize the trained classifier to predict malicious traffic classes for the testing samples. Then, we use the CP det

关键词： concept drift cyberspace security intrusion detection malicious traffic identification variational autoencoder

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Reshaping force for deformed casing repairing with hydraulic rolling reshaper and its influencing factors

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Petroleum Science 2024年第4期21卷 2745-2757页

作者： Hong-Fei li Min Luo Ting-Ting Xu Qiao-zhen li Cong-Jian Huang School of Mechanical Science and Engineering Northeast Petroleum University

Hydraulic rolling reshaper is an advanced reshaping tool to solve the problem of casing deformation,which has been widely used in recent years. When it is used for well repair operation, the reshaping force provided by ground devices is generally determined by experience. However, too large reshaping force may destroy the deformed casing, and too small reshaping force may also prolong the construction period and affect the repairing effect. In this paper, based on Hertz contact theory and elastic-plastic theory, combined with the process parameters of shaping, and considering the structural characteristics of the deformed casing and reshaper, we propose a mathematical model for calculating the reshaping force required for repairing deformed casing by hydraulic rolling reshaper. Meanwhile, the finite element model and numerical method of hydraulic rolling reshaper repairing deformed casing are established by using the finite element method, and the reliability of the mathematical model is verified by several examples. On this basis, the control variable method is used to investigate the influence of each parameter on the reshaping force, and the influence degree of each parameter is explored by orthogonal simulation test and Pearson correlation analysis. The research results not only provide an important theoretical basis for the prediction of reshaping force in on-site construction, but also provide a reference for the subsequent improvement of the shaping process.

关键词： Hydraulic rolling reshaper Reshaping force Deformed casing Casing reshaping Hertz contact theory

Influence of Nd^(3+) concentration on mid-infrared emission in PbF_(2) crystal co-doped with Ho^(3+) and Nd^(3+) ions

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Journal of Rare Earths 2024年第3期42卷 479-487,I0002页

作者： Yan Chen Juncheng Tan Peixiong Zhang Weibi zheng lin li lianhan Zhang zhen li Yin Hang zhenqiang Chen Department of Optoelectronic Engineering Jinan UniversityGuangzhou510632China Guangdong Provincial Engineering Research Centerof Crystal and Laser Technology.Guangzhou 510632China Research Center of Laser Crystal Key Laboratory of High Power Laser MaterialsShanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai201800China

A promising series of Ho_(y)Nd_(x)Pb_((1-x-y))F_2(x = 0, 0.01, 0.02, 0.03, 0.04;y = 0.02) crystals was grown by the Bridgman method. The influence of the Nd^(3+)ions concentration on mid-infrared(~2.0, ~2.9 and ~3.9 μm)fluorescence emissions of Ho^(3+)ions in the PbF_(2) crystal excited by 808 nm laser diode was investigated in this work. The energy transfer mechanism between Nd^(3+)ions and Ho~(3+)ions under different concentrations of the Nd^(3+)ions was systematically analyzed. The results show that the Nd^(3+)ions have good sensitization and deactivation effect on the Ho^(3+)ions to stimulate the mid-infrared fluorescence emissions. The experimental analysis proves that the sensitization efficiency of the Nd^(3+)ions is relatively stable at around 93.45% with varying Nd^(3+)-doping concentrations. Concentration dependence studies indicate that the concentration of the Nd^(3+)ions has significant influence on mid-infrared *** the doping concentration of the Nd^(3+)ions is up to 2.0 at%, the intensity of ~2.0, ~2.9 and ~3.9 μm emissions all reach the maximum. The output characteristics of a 3.9 μm laser are simulated, and it is found that with the increase of the Nd^(3+)-doping concentration, the peak power, pulse width, and peak energy all meet the trend of first increasing and then decreasing, and Ho_(0.02)Nd_(0.02)Pb_(0.96)F_(2) crystal displays the best performance. All the results show that the Nd^(3+)/Ho^(3+)co-doped PbF_(2) crystals might act as a useful optical medium for mid-infrared laser applications.

关键词： Crystal growth Mid-infrared PbF_(2) Rare earth ions

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