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F-doped orthorhombic Nb_(2)O_(5) exposed with 97% (100) facet for fast reversible liþ-Intercalation

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Green Energy & Environment 2024年第4期9卷 723-731页

作者： Xiaodi liu Yufeng Tang Dan Zhang Guangyin liu Xinwei Luo Yi Shang xiu li Jianmin Ma College of Chemistry and Pharmaceutical Engineering Nanyang Normal UniversityNanyang473061China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu611731China

Orthorhombic Nb_(2)O_(5)(T-Nb_(2)O_(5))is attractive for fast-charging li-ion batteries,but it is still hard to realize rapid charge transfer kinetics for li-ion ***,F-doped T-Nb_(2)O_(5) microﬂowers(F-Nb_(2)O_(5))are rationally synthesized through topotactic ***,F-Nb_(2)O_(5) are assembled by single-crystal nanoﬂakes with nearly 97%exposed(100)facet,which maximizes the exposure of the feasible li^(+)transport pathways along loosely packed 4g atomic layers to the electrolytes,thus effectively enhancing the li^(+)-intercalation ***,the band gap of F-Nb_(2)O_(5) is reduced to 2.87 eV due to the doping of F atoms,leading to enhanced electrical *** synergetic effects between tailored exposed crystal facets,F-doping,and ultrathin building blocks,speed up the li^(+)/electron transfer kinetics and improve the pseudocapacitive properties of F-Nb_(2)O_(5).Therefore,F-Nb_(2)O_(5) exhibit superior rate capability(210.8 and 164.9 mAh g^(-1) at 1 and 10 C,respectively)and good long-term 10 C cycling performance(132.7 mAh g^(-1) after 1500 cycles).

关键词： Exposed facets Orthorhombic Nb_(2)O_(5) F-doping Pseudocapacitive intercalation anode li-ion storage

Maternal weight and its association with risk of overweight in offspring:a trajectory analysis from a birth cohort in China

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World Journal of Pediatrics 2024年第5期20卷 496-505页

作者： Rui Deng Wei-Qin li Xing-xiu li liu-Mei Wei Jie Hu Jun-Hong Leng bin Dong Institute of Child and Adolescent Health School of Public HealthPeking University Health Science CenterNo.38 Xueyuan RdHaidian DistrictBeijing100191China Tianjin Women and Children’s Health Center No.96 Guizhou RdHeping DistrictTianjin300070China Menzies Health Institute Queensland Griffith UniversityNathanQLD4111Australia

Background Most studies on the association of maternal pregnancy weight with offspring weight trajectory have a short follow-up *** study aimed to explore the associations of maternal prepregnancy body mass index(BMI)and gestational weight gain(GWG)with childhood weight trajectories in a 7-year birth *** A total of 946 mother–child pairs(467 boys and 479 girls)from a longitudinal birth cohort in Tianjin City,China,were included in this study,ranging from pregnancy to offspring at 7 *** outcome variable was defined as overweight or not overweight in offspring at the last round.A group-based trajectory model was applied to identify childhood BMI trajectory *** Five discrete BMI trajectory groups were identified and characterized as constant underweight(25.2%),constant normal weight(42.8%),and high or increasing trajectory[at risk of overweight(16.9%),progressive overweight(11.0%)and progressive obesity(4.1%)].Maternal prepregnancy overweight was associated with 1.72(95%CI 1.14–2.60,P=0.01)to 4.02(95%CI 1.94–8.36,P<0.001)times the risk of all high or increasing trajectory groups,and excessive GWG was related to groups at risk of overweight[relative risk ratio(RRR)2.09,95%CI 1.27–3.46,P=0.004]and progressive obesity(RRR 3.33,95%CI 1.13–9.79,P=0.029).Children in all high or increasing trajectory groups were associated with greater overweight risk at the last round[risk ratios(RRs)ranged from 3.54(95%CI 2.53–4.95,P<0.001)to 6.18(95%CI 4.05–9.42,P<0.001)].Conclusion Maternal prepregnancy overweight and excessive gestational weight gain were associated with increasing or high-level childhood body mass index trajectories as well as a greater risk of overweight at 7 years.

关键词： Body-weight trajectory Child Gestational weight gain Overweight Pregnancy

Wild type p53 increased chemosensitivity of drug-resistant human hepatocellular carcinoma Bel7402/5-FU cells

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Acta Pharmacologica Sinica 2004年第1期 78-84页

作者： Yu-xiu li, Zhi-bin liN, Huan-ran TAN Department of Pharmacology, School of Basic Medical Sciences, Peking University, Beijing, 100083, China

AIM: To study the effect of wild type (wt) p53 gene transfection on drug resistant human hepatocellular carcinoma (HCC) cells induced by 5-Fluorouracil (5-FU). METHODS: The cytotoxicity of anticancer drugs on Bel7402 and Bel7402/5-FU cells was assessed using SRB assay. p53 expression was detected at its mRNA level by RT-PCR assay and at its protein level Western blot or immunocytochemistry assay in Bel7402/5-FU cells transfected with either control vector or wt p53. AnnexinV-FITC/PI double labeled assay was performed to detect apoptosis. The chemosensitivity of Bel7402/5-FU cells transfected with wt p53 was assessed using SRB assay. RESULTS: Bel7402/ 5-FU cells exhibited cross-resistance to vincristine, doxorubicin, paclitaxel, and so on. wt p53 gene transfection upregulated the expression of p53 in Bel7402/5-FU cells. wt p53 was able to greatly inhibit cell

关键词： hepatocellular carcinoma 5-Fluorouracil drag resistance apoptosis p53 genes transfection

MCS-based quantile value approach for reliability-based design of tunnel face support pressure

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Underground Space 2024年第5期18卷 187-198页

作者： bin li Changxing Wang Hong li Department of Road and Bridge Engineering School of Transportation and Logistics EngineeringWuhan University of TechnologyWuhan 430063China Hubei Highway Engineering Research Center Wuhan 430063China

This paper develops a new approach for reliability-based design(RBD)of tunnel face support pressure from a quantile value perspective.A surrogate model is constructed to calculate the collapse pressures of the random samples generated by a single run of Monte Carlo simulation(MCS).The cumulative distribution function(CDF)of the collapse pressure is then obtained and the support pressure aiming at a target failure probability is chosen as the upper quantile value of the collapse *** proposed approach does not require repetitive reliability analyses compared to the existing ***,a direct relationship between the target failure probability and the required support pressure is *** illustrative example is used to demonstrate the implementation *** accuracy of the reliability-based support pressures is verified by direct MCS incorporating with three-dimensional numerical ***,the influencing factors,including the sample size of MCS,the correlation coefficient between random variables,the choice of experimental points,and the surrogate model,are *** method can play a complementary role to available approaches due to its advantages of simplicity and efficiency.

关键词： Tunnel face stability Support pressure Reliability-based design Response surface method Monte Carlo simulation

Evaluation of frictional pressure drop correlations for air-water and air-oil two-phase flow in pipeline-riser system

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Petroleum Science 2024年第2期21卷 1305-1319页

作者： Nai-liang li bin Chen School of Low-carbon Energy and Power Engineering China University of Mining and TechnologyXuzhou221116JiangsuChina State Key Laboratory of Multiphase Flow in Power Engineering Xi’an Jiaotong UniversityXi’an710049ShaanxiChina

Accurate prediction of the frictional pressure drop is important for the design and operation of subsea oil and gas transporting system considering the length of the pipeline. The applicability of the correlations to pipeline-riser flow needs evaluation since the flow condition in pipeline-riser is quite different from the original data where they were derived from. In the present study, a comprehensive evaluation of 24prevailing correlation in predicting frictional pressure drop is carried out based on experimentally measured data of air-water and air-oil two-phase flows in pipeline-riser. Experiments are performed in a system having different configuration of pipeline-riser with the inclination of the downcomer varied from-2°to-5°to investigated the effect of the elbow on the frictional pressure drop in the riser. The inlet gas velocity ranges from 0.03 to 6.2 m/s, and liquid velocity varies from 0.02 to 1.3 m/s. A total of885 experimental data points including 782 on air-water flows and 103 on air-oil flows are obtained and used to access the prediction ability of the correlations. Comparison of the predicted results with the measured data indicate that a majority of the investigated correlations under-predict the pressure drop on severe slugging. The result of this study highlights the requirement of new method considering the effect of pipe layout on the frictional pressure drop.

关键词： Frictional pressure drop Pipeline-riser Gas-liquid two-phase flow Severe slugging Correlation

Rapid analysis of metal ions and organic compounds in strong acidic solutions by nano-ESI mass spectrometry

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Chinese Chemical Letters 2024年第2期35卷 516-520页

作者： Jiaquan Xu Ting li Zhendong Yu lili Song xiu-xiu Xu Hui li Jiangxi Key Laboratory for Mass Spectrometry and Instrumentation East China University of TechnologyNanchang 330013China Department of Rehabilitation Medicine The First Affiliated Hospital of Nanchang UniversityNanchang 330006China

Rapid analysis of metal ions and organic compounds in strong acidic solutions is of sustainable interest in multiple ***,complicated and time-consuming pretreatments are always required for MS analysis of the compounds in strong acidic ***,it will result in a weak signal and cause serious damage to the mass ***,a simple method inherited from nano-ESI MS was developed for rapid analysis of strong acidic ***(nL)strong acidic solution was first loaded in the nano-ESI emitter,followed by evaporation to remove the H+and leave the analytes on the wall of the nano-ESI *** evaporation process can be completed within 1 min because of the extremely tiny volume(≤1 nL)of the loaded ***,the dried analytes on the wall of the nano-ESI emitter were redissolved by loading a new solvent,followed by nano-ESI MS *** using this method,metal ions and organic compounds in the strong acidic solution can be detected with low sample consumption(1 nL),high speed(limit of detection=0.2µg/L),and high accuracy(>90%).Proof-of-concept applications of the present method have been successfully achieved for the analysis of gastric juice(pH of the sample=1),monitoring reaction catalyzed by strong acid(pH of the system=0),and micro-area analysis of ores(pH of the extraction solvent=0),showing great application potential in multiple fields.

关键词： Strong acidic solutions Nano-ESI MS Rapid analysis Reaction monitoring Micro-area analysis Gastric juice analysis

对加速城镇化时期土地利用变化核心学术问题的认识

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中国人口·资源与环境 2009年第5期19卷 1-5页

作者：李秀彬中国科学院地理科学与资源研究所北京100101

自1980年代中期起,中国就进入了城镇化加速中期阶段。该阶段土地利用变化主要特征为:建设用地快速扩张;耕地大量减少;种植业土地集约度出现拐点。影响未来中国土地利用变化最主要的因素包括:城镇化进程、农业劳动力的变化、政府生态保... 详细信息

自1980年代中期起,中国就进入了城镇化加速中期阶段。该阶段土地利用变化主要特征为:建设用地快速扩张;耕地大量减少;种植业土地集约度出现拐点。影响未来中国土地利用变化最主要的因素包括:城镇化进程、农业劳动力的变化、政府生态保护的政策。从宏观角度看,中国土地政策存在"三元悖论",即在满足粮食安全、城镇化发展、生态保护三者的土地需求之间,存在冲突。粮食安全与城镇化发展之间,属于生存与发展之间的矛盾;粮食安全与生态保护之间,属于近期目标与远期目标之间的矛盾;而生态保护与城镇化发展之间,是经济与生态效益间的矛盾。统筹和协调土地利用冲突,关键是把握土地的合理需求、集约用地的规律以及了解土地利用变化的效应。因此应加强下列三个方面的学术研究:①土地利用集约度的变化规律研究;②土地利用的合理需求分析;③土地利用变化的效应评估。

关键词：土地利用变化土地需求冲突研究重点

An Electrochemical Perspective of Aqueous Zinc Metal Anode

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Nano-Micro Letters 2024年第1期16卷 274-312页

作者： Huibo Yan Songmei li Jinyan Zhong bin li School of Materials Science and Engineering Beihang UniversityBeijing 100191People’s Republic of China

Based on the attributes of nonflammability,environmental benignity,and cost-effectiveness of aqueous electrolytes,as well as the favorable compatibility of zinc metal with them,aqueous zinc ions batteries(AZIBs)become the leading energy storage candidate to meet the requirements of safety and low ***,aqueous electrolytes,acting as a double-edged sword,also play a negative role by directly or indirectly causing various parasitic reactions at the zinc anode *** reactions include hydrogen evolution reaction,passivation,and dendrites,resulting in poor Coulombic efficiency and short lifespan of AZIBs.A comprehensive review of aqueous electrolytes chemistry,zinc chemistry,mechanism and chemistry of parasitic reactions,and their relationship is ***,the understanding of strategies for suppressing parasitic reactions from an electrochemical perspective is not profound *** this review,firstly,the chemistry of electrolytes,zinc anodes,and parasitic reactions and their relationship in AZIBs are deeply ***,the strategies for suppressing parasitic reactions from the perspective of enhancing the inherent thermodynamic stability of electrolytes and anodes,and lowering the dynamics of parasitic reactions at Zn/electrolyte interfaces are ***,the perspectives on the future development direction of aqueous electrolytes,zinc anodes,and Zn/electrolyte interfaces are presented.

关键词： Aqueous zinc ions batteries Parasitic reactions Aqueous electrolyte Zinc anode

Flocking Effects of the Stochastic Cucker-Smale System with Noise

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Journal of Systems Science & Complexity 2024年第5期37卷 1978-1994页

作者： HAN Ning GE bin li lin School of Mathematical Sciences Harbin Engineering UniversityHarbin 150001China

In this paper,the flocking behavior of a Cucker-Smale model with a leader and noise is studied in a finite *** authors present a Cucker-Smale system with two nonlinear controls for a complex network with stochastic synchronization in *** on the finite-time stability theory of stochastic differential equations,the sufficient conditions for the flocking of stochastic systems in a finite time are obtained by using the Lyapunov function ***,the numerical simulation of the particle system is carried out for the leader and noise,and the correctness of the results is verified.

关键词： Cucker-Smale model flocking behavior leader noise