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Journal of Energy Chemistry 2024年第8期95卷 241-249页

作者： Lin Su Ruining Fu Shuangying Lei Yuchen Pan Chongyang Zhu Pengcheng Liu Feng Xu SEU-FEI Nano-Pico center Key Laboratory of MEMS of the Ministry of Education Southeast University

Alloy-typed anode materials,endowed innately with high theoretical specific capacity,hold great promise as an alternative to intercalation-typed counterparts for alkali-ion batteries.Despite tremendous efforts devoted to addressing drastic volume change and severe pulverization issues of such anodes,the underlying mechanisms involving dynamic phase evolutions and reaction kinetics have not yet been fully comprehended.Herein,taking antimony（Sb） anode as a representative paradigm,its microscopic operating mechanisms down to the atomic scale during live（de）potassiation cycling are systematically unraveled using in situ transmission electron microscopy.Highly reversible phase transformations at single-particle level,that are Sb■KSb2■KSb■K5Sb4■K3Sb,were revealed during cycling.Meanwhile,multiple phase interfaces associated with different reaction kinetics coexisted and this phenomenon was properly elucidated in the context of density functional theory calculations.Impressively,previously unexplored unidirectional circulation of reaction interfaces within individual Sb particle is confirmed for both potassiation and depotassiation.Based on the empirical results,the surface diffusion-mediated potassiation-depotassiation pathways at single-particle level are suggested.This work affords new insights into energy storage mechanisms of Sb anode and valuable guidance for targeted optimization of alloy-typed anodes（not limited to Sb） toward advanced potassium-ion batteries.

关键词： Alloy-typed anode In situ transmission electron microscopy Potassium storage mechanism Reaction interface

HIV Infection and Associated Factors Among Out-of-School MSM Aged 16–24 Years—6 Cities and Tianjin Municipality,China,2022–2023

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China CDC weekly 2024年第3期6卷 45-50页

作者： Hui Liu Qiyu Zhu Lei Zhang Yujing Liu Peng Xu Mengjie Han National center for AIDS/STD Control and Prevention Chinese Center for Disease Control and PreventionBeijingChina Chinese Association of STD and AIDS Prevention and Control BeijingChina Beijing Chaoyang Kangzhong Health and education center BeijingChina

What is already known about this topic?Approximately 80%of newly diagnosed human immunodeficiency virus(HIV)cases among individuals aged 15–24 years in China are attributed to out-ofschool youth.What is added by this report?This study presents findings on HIV prevalence and comprehensive insights into HIV service utilization,risky behaviors,and prevention knowledge among young out-of-school men who have sex with men(MSM)aged 16–24 years in China.This population exhibits a disproportionately high burden of HIV,with only 51.6%of HIV cases previously diagnosed.What are the implications for public health practice?HIV services should be expanded to include these key populations.Tailored interventions are needed to remove barriers to regular HIV services faced by young key populations.

关键词： prevention remove expanded

Bias distribution and regulation in photoelectrochemical overall water-splitting cells

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National Science Review 2024年第4期11卷 141-150页

作者： Kun Dang Siqin Liu Lei Wu Daojian Tang Jing Xue Jiaming Wang Hongwei Ji Chuncheng Chen Yuchao Zhang Jincai Zhao Key Laboratory of Photochemistry CAS ResearchEducation Center for Excellence in Molecular Sciences Institute of Chemistry Chinese Academy of Sciences University of Chinese Academy of Sciences

The water oxidation half-reaction at anodes is always considered the rate-limiting step of overall water splitting（OWS）,but the actual bias distribution between photoanodes and cathodes of photoelectro chemical（PEC） OWS cells has not been investigated systematically.In this work,we find that,for PEC cells consisting of photoanodes（nickel-modified n-Si [Ni/n-Si] and α-Fe2O3） with low photovoltage(Vph 1V,the bias required for cathode activation can be significantly reduced,exhibiting a kinetics-controlled characteristic.Further investigations show that the bias distribution can be regulated by tuning the electrolyte pH and using alternative half-reaction couplings.Accordingly,a volcano plot is presented for the rational design of the overall reactions and unbiased PEC cells.Motivated by this,an unbiased PEC cell consisting of a simple Ni/n-Si photoanode and Pt cathode is assembled,delivering a photo current density of 5.3±0.2 mA cm-2.

关键词： photoelectrochemistry overall reaction cell bias distribution photoanode water splitting

Duphaston as a suitable medication for women taking intracytoplasmic sperm injection to treat infertility

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生殖与发育医学(英文) 2024年第2期8卷 89-92页

作者： Naserpour Leila Berjis Katayon Moud Sanaz Soleymani Jannatifar Rahil Department of Reproductive Biology Academic Center for Education Culture and Research (ACECR) Qom Branch Qom Iran Infertility Treatment center Academic Center for Education Culture and Research (ACECR) Qom Branch Qom Iran Cellular and Molecular Research center Qom University of Medical Sciences Qom Iran Midwifery Ward Infertility Treatment Center Academic Center for Education Culture and Research (ACECR) Qom Branch Qom Iran

Objective: Duphaston is used as an alternative to gonadotropin-releasing hormone (GnRH) antagonists for suppressing premature luteinizing hormone (LH) surges. This study aimed to compare the efficacy of Duphaston protocols with that of Cetrotide in suppressing the LH surge.Methods: In this retrospective cross-sectional study, 669 infertile women (aged 25-40 years) were administered recombinant follicle-stimulating hormone (rFSH) from the third day of their menstrual cycle. After the follicular diameter reached 13 to 14 mm, Cetrotide was prescribed orally to the control subjects, also case subjects took Duphaston orally. The retrieved oocytes were fertilized by an intracytoplasmic sperm injection (ICSI).Results: The levels of FSH, LH, and estradiol did not differ significantly between the groups (P >0.05). However, the findings indicated that Duphaston led to greater oocyte retrieval than Cetrotide (P = 0.006). However, the number of mature oocytes and viable embryos in the case subjects did not reach a significant difference compared to that in the control subjects (P >0.05). The number of good-quality embryos (stage 1) was significantly higher in the case subjects (P = 0.04). In addition, there is no significant difference in the chemical, clinical pregnancy, implantation rate, and miscarriage rate between both groups (P >0.05).Conclusion: Duphaston could be utilized as a suitable medication rather than a GnRH antagonist in women subjected to controlled ovarian hyperstimulation.

关键词： Duphaston Cetrotide Progesterone protocol Ovarian hyperstimulation GnRH antagonist

SnIP-type atomic-scale inorganic double-helix semiconductors: Synthesis, properties, and applications

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Nano Research 2024年第3期17卷 2111-2128页

作者： Mudussar Ali Bowen Zhang Muhammad Khurram Qingfeng Yan Engineering Research center of Advanced Rare Earth Materials(Ministry of education) Department of ChemistryTsinghua UniversityBeijing 100084China

Flexible inorganic double helical semiconductors similar to DNA have fueled the demand for efficient materials with innovative structures and excellent properties.The recent discovery of tin phosphide iodide(SnIP),the first carbon-free double helical semiconductor at an atomic level,has opened new avenues of research for semiconducting devices such as thermoelectric and sensor devices,solar cells,and photocatalysis.It has drawn significant academic attention due to its high structural flexibility,band gap in the visible spectrum range,and non-toxic elements.Herein,the recent progress in developing SnIP,including its prestigious structure,versatile and intriguing properties,and synthesis,is summarized.Other analogues of SnIP and SnIP-based hybrid materials and their applications in photocatalysis are also discussed.Finally,the review concludes with a critical summary and future aspects of this new inorganic semiconductor.

关键词： tin phosphide iodide(SnIP) inorganic semiconductor inorganic double helix SnIP-based hybrids photocatalysis flexible material

Progress in processing of porous titanium: a review

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Rare Metals 2024年第5期43卷 1932-1955页

作者： Xiao-Li Yang Xian-Feng Du Zhi-Lin Xu Zhong-Shuai Liang Li-Long Xiong Engineering Research center of Energy Storage Materials and Devices Ministry of Education School of Chemistry Xi'an Jiaotong University

As a novel structural and functional material,porous titanium and its alloys have been widely used in the aerospace, marine engineering and biomedical fields due to their high corrosion resistance, low density, good biocompatibility and excellent mechanical properties. Therefore, in this paper, a comprehensive review of powder metallurgy(PM)(including additive manufacturing(AM)processes) for fabricating porous titanium is firstly covered in terms of their working principles, capabilities, shortcomings and strengths. Simultaneously, the influencing factors of various methods on final pore structure of porous Ti are involved. Secondly, a summary of the chemical methods(CM) to obtain the porous Ti is also provided,such as dealloying method and reduction method. Finally,the tendency and direction of preparation technology as well as application of porous titanium were prospected.

关键词： Porous titanium Powder metallurgy Chemical method Pore structure Processing process

Observation of an upward lightning flash with 21 upward positive leaders initiated from different wind turbines in wind farm

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High Voltage 2024年第1期9卷 163-171页

作者： Li Cai Yifeng Ke Wenchao Fan Ruisheng Yan Mi Zhou Jianguo Wang Yadong Fan Engineering Research center of Ministry of education for Lightning Protection and Grounding Technology School of Electrical Engineering and AutomationWuhan UniversityWuhanChina

As the wind turbine height increases,the probability of multiple upward leaders flashes within the wind farm increases.In this study,an upward lightning flash containing 21 upward positive leaders(UPLs)initiated from different wind turbines in Zhangbei Wind Farm was analysed.The average speed of the UPLs was 1.2×10^(5) m/s,which mostly decreased to zero before reaching the cloud height.Only four UPLs developed to cloud height,with prolonged periods of bright light on three of them and with a minimum duration of 126 ms.A total of nine return strokes occurred on the other two dissipated leader channels,and the numbers of strokes on the two channels was six and three,respectively.The average interstroke interval for the return strokes was 10.5 ms.Most of these nine return strokes had peak currents smaller than 10 kA.The high-speed video frames confirmed that competition does exist between the UPLs,and the range of shielding effects increases as the height of the ULs increases.The effect of fan rotation on the initiation of upward leaders and the shielding effect between the wind turbines and upward leaders are discussed.

关键词： flash return initiated

Emerging memristors and applications in reservoir computing

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Frontiers of physics 2024年第1期19卷 219-239页

作者： Hao Chen Xin-Gui Tang Zhihao Shen Wen-Tao Guo Qi-Jun Sun Zhenhua Tang Yan-Ping Jiang School of Physics and Optoelectronic Engineering Guangdong University of TechnologyGuangzhou Higher Education Mega CenterGuangzhou 510006China

Recently, with the emergence of ChatGPT, the field of artificial intelligence has garnered widespread attention from various sectors of society. Reservoir Computing (RC) is a neuromorphic computing algorithm used to analyze time-series data. Unlike traditional artificial neural networks that require the weight values of all nodes in the trained network, RC only needs to train the readout layer. This makes the training process faster and more efficient, and it has been used in various applications, including speech recognition, image classification, and control systems. Its flexibility and efficiency make it a popular choice for processing large amounts of complex data. A recent research trend is to develop physical RC, which utilizes the nonlinear dynamic and short-term memory properties of physical systems (photonic modules, spintronic devices, memristors, etc.) to construct a fixed random neural network structure for processing input data to reduce computing time and energy. In this paper, we introduced the recent development of memristors and demonstrated the remarkable data processing capability of RC systems based on memristors. Not only do they possess excellent data processing ability comparable to digital RC systems, but they also have lower energy consumption and greater robustness. Finally, we discussed the development prospects and challenges faced by memristors-based RC systems.

关键词： reservoir computing memristor resistive switching artificial synapse neuromorphic computing

Comparative analysis between single-train passing and double-train intersection in a tunnel

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2024年第5期25卷 429-442页

作者： Jianming DU Qian FANG Xuan ZHANG Hualao WANG Bridge and Tunnel Research center Research Institute of Highway Ministry of TransportBejing 100088China Tunnel and Underground Engineering Research center of Ministry of education Beijing Jiaotong UniversityBeijing 00044China

Aerodynamic pressure significantly impacts the scientific evaluation of tunnel service performance.The aerodynamic pressure of two trains running in a double-track tunnel is considerably more complicated than that of a single train.We used the numerical method to investigate the difference in aerodynamic pressure between a single train and two trains running in a double-track tunnel.First,the numerical method was verified by comparing the results of numerical simulation and on-site monitoring.Then,the characteristics of aerodynamic pressure were studied.Finally,the influence of various train-tunnel factors on the characteristics of aerodynamic pressure was investigated.The results show that the aerodynamic pressure variation can be divided into stage I:irregular pressure fluctuations before the train tail leaves the tunnel exit,and stage II:periodic pressure declines after the train tail leaves the tunnel exit.In addition,the aerodynamic pressure simultaneously jumps positively or drops negatively for a single train or two trains running in double-track tunnel scenarios.The pressure amplitude in the two-train case is higher than that for a single train.The maximum positive peak pressure difference(P_(STP))and maximum negative peak pressure difference(P_(STN))increase as train speed rises to the power from 2.256 to 2.930 in stage I.The P_(STP) and P_(STN) first increase and then decrease with the increase of tunnel length in stage I.The P_(STP) and P_(STN) increase as the blockage ratio rises to the power from 2.032 to 2.798 in stages I and II.

关键词： Railway tunnel Aerodynamic effect Pressure characteristic Train speed Tunnel length Blockage ratio

Learning topological defects formation with neural networks in a quantum phase transition

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Communications in Theoretical Physics 2024年第5期76卷 68-76页

作者： Han-Qing Shi Hai-Qing Zhang center for Gravitational Physics Department of Space ScienceBeihang UniversityBeijing 100191China Peng Huanwu Collaborative center for Research and education Beihang UniversityBeijing 100191China

Neural networks possess formidable representational power,rendering them invaluable in solving complex quantum many-body systems.While they excel at analyzing static solutions,nonequilibrium processes,including critical dynamics during a quantum phase transition,pose a greater challenge for neural networks.To address this,we utilize neural networks and machine learning algorithms to investigate time evolutions,universal statistics,and correlations of topological defects in a one-dimensional transverse-field quantum Ising model.Specifically,our analysis involves computing the energy of the system during a quantum phase transition following a linear quench of the transverse magnetic field strength.The excitation energies satisfy a power-law relation to the quench rate,indicating a proportional relationship between the excitation energy and the kink numbers.Moreover,we establish a universal power-law relationship between the first three cumulants of the kink numbers and the quench rate,indicating a binomial distribution of the kinks.Finally,the normalized kink-kink correlations are also investigated and it is found that the numerical values are consistent with the analytic formula.

关键词： neural networks machine learning transverse-field quantum Ising model kibble-zurek mechanism

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