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Chinese Journal of Chemical Engineering 2024年第5期69卷 238-249页

作者： yuehua yao Fan Wang Yinguang Xu Zishuai Xu Lizhen Chen Jianlong Wang School of Chemistry and Chemical Engineering North University of ChinaTaiyuan 030051China Gansu Yinguang Chemical Industry Group Co.Ltd. Baiyin 730900China

In order to remove hexahydro-1,3,5-trinitro-1,3,5-triazine(RDX),the main impurity,in process of polymorphic transformation of octrahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine(HMX),the solubility ofβ-HMX and RDX in acetonitrile(ACN)+water in the temperature range of 288.15-333.15 K and in nitric acid(HNO_(3))+water in the temperature range of 298.15-333.15 K were measured by laser dynamic *** results showed that the solubility of bothβ-HMX and RDX in binary mixed solvents increased monotonously as the temperature increase at a given solvent composition or with increasing of mole fraction of solvent(ACN and nitric acid).Solubility data were well correlated by the modified Apelblat equation,Jouyban-Acree model,Yaws equation and van't Hoff equation,and the Yaws equation achieved the best fitting results according to the relative error and the mean square error ***,the solubility ofβ-HMX and RDX in binary mixed solvent was compared,based on the solubility difference and the solvent's own properties,the best separation degree ofβ-HMX and RDX was found when the mole fraction of nitric acid was 0.22 at room temperature,which provided data support for HMX crystallization in mixed *** solubility differences between RDX andβ-HMX in mixed solvents were explained from the formation of intermolecular and intramolecular hydrogen bonds.

关键词： Solubility Octrahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine Hexahydro-1,3,5-trinitro-1,3,5-triazine Separation Model Hydrogen bond

Zr_(x)Ce_(1-x)O_(2)/NC催化CO_(2)和苯乙烯⁃锅法制环碳酸酯

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中北大学学报（自然科学版） 2024年第2期45卷 229-238页

作者：周钰淼梁栋姚悦华武越赵婷朱娜中北大学化学与化工学院山西太原030051 山西新华化学防护设备研究所山西太原030008 山西大学环境与资源学院山西太原030006

CO_(2)与烯烃转化为环碳酸酯是当前一种有效的固碳策略,为此设计了一种掺氮多孔碳负载锆铈双金属(Zr_(x)Ce_(1-x)O_(2)/NC)催化剂。通过X射线衍射(XRD)、扫描电子显微镜(SEM)、N_(2)-吸附、CO_(2)和NH_(3)程序升温脱附(CO_(2)-TPD和NH_(... 详细信息

CO_(2)与烯烃转化为环碳酸酯是当前一种有效的固碳策略,为此设计了一种掺氮多孔碳负载锆铈双金属(Zr_(x)Ce_(1-x)O_(2)/NC)催化剂。通过X射线衍射(XRD)、扫描电子显微镜(SEM)、N_(2)-吸附、CO_(2)和NH_(3)程序升温脱附(CO_(2)-TPD和NH_(3)-TPD)等表征了催化剂的形貌、物相、孔结构以及酸碱两性特征。结果表明,该催化剂可在无卤条件下催化CO_(2)和苯乙烯一锅法制备环碳酸酯,特别是Zr_(0.75)Ce_(0.25)O_(2)/NC在2 MPa CO_(2)下,采用80℃/8 h和150℃/8 h分段工艺,实现了74.87%的转化率和80.43%的环碳酸酯选择性,这归因于氧化铈(CeO_(2))和氧化锆(ZrO_(2))在碳载体上的均匀分散,以及丰富的酸-碱性位点协同作用。

关键词： CO_(2) 苯乙烯 CeO_(2) ZrO_(2) 多孔碳环碳酸酯

合并EB病毒感染的儿童肺炎支原体肺炎临床特点及中医证型分析

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亚太传统医药 2024年第7期20卷 120-124页

作者：宋均亚赵西斌张恩胜王艳姚月华姜宁青岛大学附属山东省妇幼保健院儿科山东济南250014

目的:分析肺炎支原体肺炎(MPP)合并EB病毒(EBV)感染患儿的中医证型分布,及各证型与发病特点、临床表现等临床资料的关系。方法:回顾性收集2020年1月-2023年1月山东省妇幼保健院儿科收治的MPP患儿的临床资料,按是否存在EBV感染,分为MP混... 详细信息

目的:分析肺炎支原体肺炎(MPP)合并EB病毒(EBV)感染患儿的中医证型分布,及各证型与发病特点、临床表现等临床资料的关系。方法:回顾性收集2020年1月-2023年1月山东省妇幼保健院儿科收治的MPP患儿的临床资料,按是否存在EBV感染,分为MP混合EBV感染患儿及单纯MP感染患儿。统计MP混合EBV感染患儿的证型分布情况,并分析临床资料与中医证型之间的关系。结果:该研究共纳入573例MPP患儿,混合EBV感染者达36.13%。MP混合EBV感染患儿在证型分布上以痰热闭肺证为主(P<0.05);发病年龄上,风热闭肺证多见于婴幼儿(P<0.05),痰热闭肺证多见于学龄前期和学龄期儿童(P<0.05);在发热特点上,痰热闭肺证患儿热程较长、热峰更高(P<0.05);痰热闭肺证患儿CRP水平显著高于其他各证型(P<0.05);在并发症上,痰热闭肺证患儿更易发生肝损害,出现肺实变,进展为重症/难治性支原体肺炎(P均<0.05),且平均住院时间最长(P<0.05)。结论:MPP混合EBV感染的患儿在辨证上以痰热闭肺证为主,学龄前期、学龄期儿童高发,痰热闭肺证患儿临床表现严重且复杂,对于MPP患儿,尤其是出现发热时间长、CRP升高、肺实变、肝损害及进展为难治性或重症MPP,辨证为痰热闭肺证时,应警惕存在EBV混合感染的可能,可进行EBV检测,有利于早期、正确地临床诊断及治疗。

关键词：肺炎支原体肺炎 EB病毒儿童临床特点中医证型

Associations Between Air Temperature and Daily Varicella Cases—Jinan City,Shandong Province,China,2019–2021

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China CDC weekly 2024年第2期6卷 36-39,I0008,I0009页

作者： Guijie Luan yuehua Hu Meng Chen Meiying You Chengdong Xu Dapeng Yin Jianjun Liu Hongyan yao Chinese Center for Disease Control and Prevention BeijingChina Institute for Immunization management Shandong Center forDisease Control and PreventionJinan CityShandong ProvinceChina State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingChina Hainan Provincial Center for Disease Control and Prevention Haikou CityHainan ProvinceChina.

What is already known about this topic?The impact of air temperature on varicella has been studied,but there is limited research exploring its effect on varicella by gender and age *** is added by this report?We conducted a time series analysis to examine the differential effects of air temperature on varicella infection across different demographic *** findings indicate that lower temperatures have a more pronounced influence on varicella incidence among males and children compared to females and *** are the implications for public health practice?These findings can assist in identifying populations that are vulnerable to temperature-related varicella and in guiding the implementation of effective measures for varicella control.

关键词： finding measures Shandong

A novel topology with controllable wideband baseband impedance for power amplifiers

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Frontiers of Information Technology & Electronic Engineering 2024年第2期25卷 308-315页

作者： yao yao Zhijiang DAI Mingyu LI School of Intelligent Technology and Engineering Chongqing University of Science and TechnologyChongqing400065China School of Microelectronics and Communication Engineering Chongqing UniversityChongqing400065China

This paper presents a novel topology to control the baseband impedance of a power amplifier(PA)to avoid performance deterioration in concurrent dual-band *** topology can avoid pure resonance of capacitors and inductors LC,which leads to a high impedance at some frequency ***,it can be applied to transmitters that are excited by broadband *** particular,by adjusting the circuit parameters and increasing stages,the impedance of the key frequency bands can be flexibly controlled.A PA is designed to support this design *** saturated output power is around 46.7 dBm,and the drain efficiency is>68.2%(1.8-2.3 GHz).Under concurrent two-tone excitation,the drain efficiency reaches around 40%even under 5.5 dB back-off power with the tone spacing from 10 MHz to 500 *** results demonstrate that the proposed topology is capable of controlling wideband baseband impedance.

关键词： Baseband impedance Concurrent dual-band Power amplifier

Fresh-Keeping Decision and Coordination of Fresh Agricultural Product Supply Chain Considering Carbon Cap-and-Trade under Different Dominance

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Journal of Systems Science and Systems Engineering 2024年第1期33卷 30-51页

作者： Yang Yang Guanxin yao China Institute for Agricultural Equipment Industrial Development Jiangsu UniversityZhenjiang212013China Jiangsu Modern Logistics Research Base Yangzhou UniversityYangzhou225009China

In the context of low carbon,this paper discussed the impact of the carbon cap-and-trade policy on the fresh-keeping decision-making of two-echelon fresh agricultural product supply chains under different dominance,and designed cost-sharing contracts to coordinate the supply chain of fresh agricultural products dominated by suppliers and retailers *** results showed that:dominance has no effect on the fresh-keeping decision and total revenue of fresh agricultural product supply chain,but it affects the internal income distribution,and dominance does not always bring more benefits;the implementation of carbon cap-and-trade reduces the fresh-keeping decision-making of fresh agricultural products supply chain and reduces the free-rider income of followers;the role of higher carbon trading price is twofold,which not only brings about the speculation of leading enterprises,but also promotes the application of low-carbon technologies;consumers’high preference for freshness,low-cost and high-efficiency low-carbon technology are all conducive to improving the fresh-keeping efforts and benefits of the supply chain;cost-sharing contracts can coordinate the supply chain of fresh agricultural products.

关键词： Dominant power carbon cap-and-trade policy fresh agricultural product supply chain fresh-keeping decision-making

Numerical investigation of non-uniform temperature fields for proppant and fluid phases in supercritical CO_(2)fracturing

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Particuology 2024年第7期90卷 149-163页

作者： Boyu Liu Jun yao Research Center of Multiphase Flow in Porous Media China University of Petroleum(East China)Qingdao 266000China

The non-uniform temperature distribution in supercritical CO_(2)(Sc-CO_(2))fracturing influences the density,viscosity,and volume expansion or shrinkage rate of Sc-CO_(2),impacting proppant *** study presents a coupled computational fluid dynamics-discrete element method and heat transfer model to examine the effects of proppant bed shape and the heat transfers of proppant-wall,proppant-fluid,and fluid-wall on the fluid and proppant temperature *** Sc-CO_(2)volume expansion is assessed under various temperature conditions by evaluating the volume-averaged Sc-CO_(2)*** factors,including proppant size,shape,thermal conductivity,concentration,temperature difference,and injection velocity,are carefully analyzed to elucidate their *** findings elucidate the existence of four distinct zones in the fluid temperature *** zone exhibits different magnitudes of temperature change under diverse conditions and undergoes dynamic transformations with the development of the proppant *** fluid-wall heat transfer and the fluid temperatures in Zones C and D are significantly subject to the fluid injection velocity(governing the heating duration),the temperature difference between fluid and formation(impacting the magnitude of heat flux),and the proppant bed shape(controlling the effective heating area).Additionally,the proppant-wall and proppant-fluid heat transfers determine the temperatures of both the proppant bed and the fluid within Zone B,showing a strong correlation with proppant thermal conductivity,proppant size,injection velocity,and temperature *** proposed coupled model provides valuable insights into the temperature distributions and flow behaviors of temperature-dependent fracturing fluids and proppants.

关键词： CFD-DEM Heat transfer Compressible fluid CO_(2)sequestration Proppant transport

Limits of Uneven Battery Power in Modular Multilevel Converter-based Battery Energy Storage Systems

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CSEE Journal of Power and Energy Systems 2024年第2期10卷 686-695页

作者： yao Pan Xiaofeng Sun Wei Zhao Xin Li yao Cai Institute of Electrical Engineering Yanshan UniversityQinhuangdao 066004China

For modular multilevel converter-based battery energy storage systems (MMC-BESS), uneven power among batteries of SMs will be deduced by battery aging, battery fault, etc., which will degrade performance and even lead to system failure. For maintaining the balance of capacitor voltage, this paper analyzes the limits of the uneven power of batteries, which are presented as the current limits in this paper. According to analysis, an analytical method is proposed that only the dc and fundamental frequency components of the arm current are used to calculate current limits. With the current limits it is able to evaluate the reasonability of power distribution among batteries. Meanwhile, increase of fundamental frequency component will enhance the current limits, and the dc component determines the size relationship between the absolute values of the upper and lower current limits. Finally, simulation model and experiment prototype are built for verifying the theoretical analysis and current limits calculation method, and satisfactory results are provided.

关键词： Arm current balance of capacitor voltage current limits MMC-BESS uneven power

Reinforcement learning based adaptive control for uncertain mechanical systems with asymptotic tracking

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Defence Technology（防务技术） 2024年第4期34卷 19-28页

作者： Xiang-long Liang Zhi-kai yao yao-wen Ge Jian-yong yao School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China College of Automation&College of Artificial Intelligence Nanjing University of Post and TelecommunicationNanjing210023China

This paper mainly focuses on the development of a learning-based controller for a class of uncertain mechanical systems modeled by the Euler-Lagrange *** considered system can depict the behavior of a large class of engineering systems,such as vehicular systems,robot manipulators and *** these systems are often characterized by highly nonlinear characteristics,heavy modeling uncertainties and unknown perturbations,therefore,accurate-model-based nonlinear control approaches become *** by the challenge,a reinforcement learning(RL)adaptive control methodology based on the actor-critic framework is investigated to compensate the uncertain mechanical *** approximation inaccuracies caused by RL and the exogenous unknown disturbances are circumvented via a continuous robust integral of the sign of the error(RISE)control *** from a classical RISE control law,a tanh(·)function is utilized instead of a sign(·)function to acquire a more smooth control *** developed controller requires very little prior knowledge of the dynamic model,is robust to unknown dynamics and exogenous disturbances,and can achieve asymptotic output ***,co-simulations through ADAMS and MATLAB/Simulink on a three degrees-of-freedom(3-DOF)manipulator and experiments on a real-time electromechanical servo system are performed to verify the performance of the proposed approach.

关键词： Adaptive control Reinforcement learning Uncertain mechanical systems Asymptotic tracking

Lesson Learned from COVID-19 Retrospective Study: An Entropy-Based Clinical-Interpretable Scorecard for Mortality Risk Control at ICU Admission

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Tsinghua Science and Technology 2024年第1期29卷 34-45页

作者： Chong yao Chonghui Huangqi Anpeng Huang Laboratory of Network Information Security Beihang UniversityBeijing 100191China Andrew and Erna Viterbi School of Engineering University of Southern CaliforniaLos AnglesCA 90089USA Beijing Goodwill Information and Technology Co. Ltd.and Mobile Health LaboratoryPeking UniversityBeijing 100871China

With severe acute respiratory syndrome coronavirus 2 spreading globally and causing 2019 coronavirus disease(COVID-19),a challenge that we unprepared for was about how to optimally plan and distribute limited top-medical resources for patients in need of urgent *** address this challenge,physicians desperately needed a scientific tool to methodically differentiate between cases with varying *** this study,the unique data of COVID-19 intensive care unit(ICU)patients provided by the national medical team in Wuhan were classified into discrete and continuous variable *** continuous data were discretized using an entropy-based method and transformed into serial information margins,in which each information margin is related to a specific symptom or clinical ***,all these native and processed discrete data were used to configure a readable scorecard through logistic regression,which is the desired scientific tool aforementioned.A total of 322 ICU patients(age:[median:64,interquartile range:54-75],males:178[55.28%],and death:72[22.36%])were included in the *** of mortality in COVID-19 patients can be evaluated using a scorecard model(calibration slope:1.343,Brier:0.048,Dxy=0.972,and population stability index=0.071),with desired model performances(accuracy=0.948,area under curve=0.99,sensitivity=1,and specificity=0.939).This new model can interpret clinical meanings from complex data,and compare it with existing machine learning methods through a black-box *** new data-information model answers a critical question of how a computing algorithm produces clinically meaningful results that will help physicians logically allocate medical resources for COVID-19 ***,this tool has limitations,giving that this research is a retrospective ***,this tool will be tested further and optimized for adaptation to similar clinical cases in the future.

关键词： COVID-19 scorecard clinical-interpretable machine learning ICU admission control