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林分密度对兴安落叶松径向生长-气候关系的影响

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南京林业大学学报（自然科学版） 2024年第2期48卷 182-190页

作者：韩新宇高露双秦莉庞荣荣刘鸣谦朱一泓田益雨张金北京林业大学林学院北京100083 中国气象局乌鲁木齐沙漠气象研究所新疆乌鲁木齐830002 University of California BerkeleyBerkeley California 94704 乌尔旗汉森林工业有限公司内蒙古呼伦贝尔022159

【目的】研究不同密度下兴安落叶松径向生长与气候因子动态关系,为全球变暖背景下兴安落叶松林可持续经营中合理的林分密度确定提供依据。【方法】根据林分密度指数(SDI)选取大兴安岭中北部地区低、中和高3种林分密度梯度兴安落叶松(Lar... 详细信息

【目的】研究不同密度下兴安落叶松径向生长与气候因子动态关系,为全球变暖背景下兴安落叶松林可持续经营中合理的林分密度确定提供依据。【方法】根据林分密度指数(SDI)选取大兴安岭中北部地区低、中和高3种林分密度梯度兴安落叶松(Larix gmelinii)纯林为研究对象,采用Mann-Kendall检验确定研究区气温突变点,基于野外调查和树轮数据,分析气温突变点后各林分密度下兴安落叶松径向生长趋势,并利用皮尔森相关和滑动相关分析其与各气候因子的关系及稳定性。【结果】在气温突变点后,研究区域兴安落叶松生长出现增强和衰退趋势,且随着林分密度增加,树木生长衰退比例增高。高林分密度下兴安落叶松生长受抑制程度最高,1988—1990年平均生长变化率为-25%,处于衰退状态。林分密度改变了兴安落叶松生长对气候的响应关系,高密度下衰退组树木生长与8月标准化降水蒸散指数(SPEI)正相关关系最强(P<0.05),与夏季温度呈稳定的显著负相关关系(P<0.05)。研究区气候呈现明显暖干化趋势,而低林分密度兴安落叶松保持54%的生长增强比例,树木与温度由低密度下的正相关关系向高密度的负相关关系转变。【结论】气温发生显著改变后,随着林分密度增加,树木生长衰退比例增高。低密度林分对干旱的抵抗力较强,而高密度林分增强了树木生长对气候因子的敏感性。因此,较低林分密度可以减缓气候变暖对兴安落叶松生长带来的负面影响,调整林分密度成为减缓兴安落叶松林树木生长衰退趋势的必要经营措施。

关键词：兴安落叶松林分密度径向生长气候因子

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一种非常紧凑的掩码AES的硬件设计与实现

密码学报（中英文） 2024年第3期11卷 662-680页

作者：隋谦周佳运祝一豪苏杨许森王伟嘉无山东大学网络空间安全学院青岛266237 泉城省实验室济南250103 观源(上海)科技有限公司上海200241

差分能量分析作为一种强大的侧信道攻击手段,已经严重威胁到密码算法硬件实现的安全性,目前防护此类攻击最有效的方法就是对密码算法进行掩码处理.在AES算法中只有S盒是非线性的,因此如何安全高效地实现S盒一直是密码学领域的研究热点之... 详细信息

差分能量分析作为一种强大的侧信道攻击手段,已经严重威胁到密码算法硬件实现的安全性,目前防护此类攻击最有效的方法就是对密码算法进行掩码处理.在AES算法中只有S盒是非线性的,因此如何安全高效地实现S盒一直是密码学领域的研究热点之一.本文在De Meyer等人研究工作的基础上,提出了一种具有已知最小面积的掩码S盒的串行化实现方案.先将用于零值处理的Kronecker Delta函数串行化,接着通过共享一个8位乘法器模块用于求逆以及布尔掩码和乘法掩码之间的转换,最后加上仿射变换以最小的面积代价实现了S盒.本文将S盒应用于AES算法,并且提供了掩码AES的串行化实现方案,同时给出了该方案的面积下限,在此基础上,对S盒及AES算法的部分结构进行调整,为未来的工作提供了一系列权衡面积和延迟的手段.实验表明,在可比的随机数成本下,本文S盒的一阶掩码和二阶掩码实现以一定延迟为代价将面积分别降低了48%和70%, AES算法的一阶掩码和二阶掩码实现分别降低10%和21%,并且随着安全阶数的增大,本文实现方案对面积的优化幅度会进一步提高.最后,在实验中通过对从SAKURA-G板上获取的轨迹执行固定与随机的Welch T测试来验证实现的安全性,对于AES算法的一阶掩码和二阶掩码实现分别采集了多达50万条曲线,没有发现泄漏点.

关键词： S盒掩码 AES 侧信道攻击电路面积

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一种在线迭代的水下随机传感器阵列生成算法

电子信息对抗技术 2024年第1期39卷 68-74页

作者：田蕴琦朱磊夏碧君曾跃胜中国电子科技集团公司第二十九研究所成都610036 电磁空间安全全国重点实验室成都610036

水下攻防对抗体系逐渐向无人化、网络化发展。为降低水声通信对水下传感器网探测能力的制约,首先分析了水下通信方式的应用特点,提出了水下随机传感器分布式阵列通信方式应用方案。然后结合凝聚式分类技术,建立距离矩阵和通信关系矩阵,... 详细信息

水下攻防对抗体系逐渐向无人化、网络化发展。为降低水声通信对水下传感器网探测能力的制约,首先分析了水下通信方式的应用特点,提出了水下随机传感器分布式阵列通信方式应用方案。然后结合凝聚式分类技术,建立距离矩阵和通信关系矩阵,提出了一种基于通信距离的在线迭代阵列生成算法,并给出了算法流程和计算实例。最后通过仿真试验验证了算法的有效性,并与规则阵列进行了对比分析。

关键词：水下无线传感器网络水下通信随机阵列分布式阵列

整体护理干预在小儿急性支气管炎中的应用效果

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妇儿健康导刊 2024年第10期3卷 115-118页

作者：朱安娜宋时艳田丽丽滨州医学院附属医院儿童呼吸科病区山东滨州256600

目的观察整体护理干预在小儿急性支气管炎中的应用效果。方法选择2022年9月至2023年8月滨州医学院附属医院儿童呼吸科收治的80例急性支气管炎患儿,采用摸球法分为两组。对照组(40例)接受常规护理干预,研究组(40例)接受整体护理干预,比... 详细信息

目的观察整体护理干预在小儿急性支气管炎中的应用效果。方法选择2022年9月至2023年8月滨州医学院附属医院儿童呼吸科收治的80例急性支气管炎患儿,采用摸球法分为两组。对照组(40例)接受常规护理干预,研究组(40例)接受整体护理干预,比较两组护理效果。结果研究组护理总满意率为97.50%,高于对照组的77.50%(P<0.05);研究组各临床症状(喘憋、咳嗽、肺部哮鸣音)消失时间[(3.13±1.02)、(3.42±1.20)、(4.55±1.24)d]及体温恢复时间[(2.08±0.51)d]短于对照组[(5.59±1.42)、(5.88±1.62)、(7.64±1.56)、(3.98±0.76)d](P<0.05);研究组治疗总依从率(95.00%)高于对照组(75.00%)(P<0.05)。结论整体护理在急性支气管炎患儿中应用效果良好,可提高护理满意度,缩短临床症状消失时间及体温恢复时间,提升治疗依从性,值得推广。

关键词：整体护理干预小儿急性支气管炎满意度临床症状治疗依从性

Effect of Integrated Chinese and Western Medicine Therapy on Severe Hand, Foot and Mouth Disease: A Prospective, Randomized, Controlled Trial

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Chinese Journal of Integrative Medicine 2017年第12期23卷 887-892页

作者： LI Xiu-hui LI Shuang-jie XU yi WEI Dan SHI Qing-sheng zhu Qing-xiong YANG Tong DING Jian-bo tian yi-mei HUANG Ji-han WANG Kun WEN Tao ZHANG Xi Department of Integrated Traditional Chinese Medicine and Western Medicine Beijing Youan Hospital Affiliated to Capital Medical University Department of Communicable Diseases Children's Hospital of Hunan Province Department of Pediatrics Guangzhou Medical Center for Women and Children Department of Pediatrics First Hospital Affiliated to Guangxi Medical University Department of Internal Medicine Handan Maternal and Child Health Hospital Department of Internal Medicine Children's Hospital of Jiangxi Province Department of Pediatrics The People's Hospital of Liuzhou Center for Drug Clinical Research Shanghai University of Chinese Medicine Medical Research Center Beijing Chaoyang HospitalCapital Medical University Department of Pediatrics Kaifeng Children's Hospital

Objective: To evaluate the efficacy and safety of Chinese medicine(CM) plus Western medicine(WM) in the treatment of pediatric patients with severe hand, foot and mouth disease(HFMD) by conducting a prospective, controlled, and randomized trial. Methods: A total of 451 pediatric patients with severe HFMD were randomly assigned to receive WM therapy alone(224 cases, WM therapy group) or CM [Reduning Injection(热毒宁注射液) or Xiyanping Injection(喜炎平注射液)] plus WM therapy(227 cases, CM plus WM therapy group) for 7–10 days, according to a web-based randomization system. The primary outcome was fever clearance time, which was presented as temperature decreased half-life time. The secondary outcomes included the rate of rash/herpes disappearance within 120 h, as well as the rate for cough, runny nose, lethargy and weakness, agitation or irritability, and vomiting clearance within 120 h. The drug-related adverse events were also recorded. Results: The temperature decreased half-life time was 40.4 h in the WM therapy group, significantly longer than 27.2 h in the CM plus WM therapy group(P<0.01). Moreover, the rate for rash/herpes disappearance within 120 h was 43.6%(99/227) in the CM plus WM therapy group, significantly higher than 29.5%(66/224) in the WM therapy group(P<0.01). In addition, the rate for cough, lethargy and weakness, agitation or irritability disappearance within 120 h was 32.6%(74/227) in the CM plus WM therapy group, significantly higher than 19.2%(43/224) in the WM therapy group(P<0.01). No drug-related adverse events were observed during the course of the study. Conclusions: The combined CM and WM therapy achieved a better therapeutic efficacy in treating severe HFMD than the WM therapy alone. Reduning or Xiyanping Injections may become an important complementary therapy to WM for relieving the symptoms of severe HFMD.

关键词： hand foot and mouth disease Reduning Injection Xiyanping Injection Chinese medicine

LETRNG—A Lightweight and Efficient True Random Number Generator for GNU/Linux Systems

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Tsinghua Science and Technology 2023年第2期28卷 370-385页

作者： Yucong Chen Fangfang zhu Yanshan tian Shuaixin Xu Lihong Han Qingguo Zhou Nam Ling School of Information Science and Engineering Lanzhou UniversityLanzhou 730000China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China Department of Computer Science and Engineering Santa Clara UniversitySanta ClaraCA 95053 USA

Unpredictable and irreproducible digital keys are required to modulate security-related information in secure communication *** random number generators(TRNGs)rather than pseudorandom number generators(PRNGs)are required for the highest level of *** is a significant component in the digital security realm for extracting unpredictable binary ***,most TRNGs extract high-quality“noise”from unpredictable physical random ***,these applications must be equipped with external hardware for collecting entropy and converting them into a random digital *** study introduces a lightweight and efficient true random number generator(LETRNG)that uses the inherent randomness of a central processing unit(CPU)and an operating system(OS)as the source of *** then utilize a lightweight post-processing method based on XOR and fair coin operation to generate an unbiased random binary *** based on two famous test suites(NIST and ENT)show that LETRNG is perfectly capable of generating high-quality random numbers suitable for various GNU/Linux systems.

关键词： GNU/Linux system true random number generator complex system inherent randomness nondeterminism

Waterbomb-origami inspired triboelectric nanogenerator for smart pavement-integrated traffic monitoring

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Nano Research 2022年第6期15卷 5450-5460页

作者： Yafeng Pang Xingyi zhu ying Yu Shuainian Liu Yu Chen yi Feng Key Laboratory of Road and Traffic Engineering of Ministry of Education Tongji UniversityShanghai 200092China Department of Civil and Environmental Engineering Shantou UniversityShantou 515063China School of Mechanical Engineering Tongji UniversityShanghai 200092China College of Electronic and Information Engineering Tongji UniversityShanghai 200092China

With a rapid development of intelligent transportation systems(ITSs),traffic monitoring has gained increasing ***,we present a new kind of waterbomb-origami-inspired triboelectric nanogenerator(WO-TENG)as a traffic monitoring system to integrate smart pavement with lightweight,cost-effective,excellent deformability,flexibility,and self-rebounding *** electrical performance is significantly improved by more than 67%compared with current origami-based TENG,and multi tribo-pairs have great *** fully-packaged self-driven WO-TENG is further developed to integrate smart pavement,which can successfully decouple the influence of vehicle speed and weight on the sensing *** phenomenon demonstrates the feasibility and stability of the WO-TENG for traffic *** of the voltage amplitude and time interval electrical wave,vehicle speed,number of vehicles,and types of vehicles can be further evaluated *** work can not only address the challenge of traditional traffic monitoring system,but also promote the development of TENG based self-powered sensors in ITSs.

关键词： waterbomb-origami triboelectric nanogenerator smart pavement traffic monitoring

Tracking structural evolution: operando regenerative CeOx/Bi interface structure for high-performance CO2 electroreduction

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National Science Review 2021年第7期8卷 158-166页

作者： Ruichao Pang Pengfei tian Hongliang Jiang Minghui zhu Xiaozhi Su Yu Wang Xiaoling Yang yihua zhu Li Song Chunzhong Li Key Laboratory for Ultrafine Materials of Ministry of Education School of Chemical Engineering East China University of Science and Technology Shanghai Engineering Research Center of Hierarchical Nanomaterials School of Materials Science and Engineering East China University of Science and Technology Shanghai Institute of Applied Physics Chinese Academy of Sciences National Synchrotron Radiation Laboratory University of Science and Technology of China

Unveiling the structural evolution and working mechanism of catalysts under realistic operating conditions is crucial for the design of efficient electrocatalysts for CO;2;electroreduction,yet remains highly ***,by virtue of operando structural measurements at multiscale levels,it is identified under CO;2;electroreduction conditions that an as-prepared CeO;2;/BiOCl precatalyst gradually evolves into CeO;x;/Bi interface structure with enriched Ce;3+;species,which serves as the real catalytically active *** derived CeO;x;/Bi interface structure compared to pure Bi counterpart delivers substantially enhanced performance with a formate Faradaic efficiency approaching 90% for 24 hours in a wide potential *** formate Faradaic efficiency can be further increased by using isotope D;2;O instead of H;2;*** functional theory calculations suggest that the regenerative CeO;x;/Bi interfacial sites can not only promote water activation to increase local *H species for CO;2;protonation appropriately,but also stabilize the key intermediate *OCHO in formate pathway.

关键词： CO2 electroreduction electrocatalyst nanosheet structural evolution interface

超高效液相色谱-串联高分辨质谱法测定白酒接触材料中双酚A、双酚F和双酚S的迁移量

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食品与发酵工业 2024年第10期50卷 306-311页

作者：朱霞建蒋力力尚煜豪田栋伟程平言胡建锋汪地强贵州习酒股份有限公司贵州遵义564622

建立了白酒接触塑料制品中双酚A、双酚F、双酚S的超高效液相色谱-串联高分辨质谱的检测方法。双酚A、双酚F、双酚S在食品模拟液中经过一定时间和温度后发生迁移,以0.1%氨水-甲醇为流动相洗脱,经C18色谱柱分离,结合加热电喷雾电离源,在... 详细信息

建立了白酒接触塑料制品中双酚A、双酚F、双酚S的超高效液相色谱-串联高分辨质谱的检测方法。双酚A、双酚F、双酚S在食品模拟液中经过一定时间和温度后发生迁移,以0.1%氨水-甲醇为流动相洗脱,经C18色谱柱分离,结合加热电喷雾电离源,在负离子模式下采用Full MS/ddMS^(2)进行分析;该方法在2.50~500.00μg/L质量浓度内线性良好,相关系数R^(2)均大于0.990,双酚S、双酚F和双酚A检出限分别为0.98、1.06、1.12μg/L,加标回收率为95.70%~117.53%,相对标准偏差为1.00%~3.55%。该方法灵敏度高、操作简便、定性准确性高,适用于白酒接触塑料制品中双酚A、双酚F、双酚S的检测,为开展酒类食品安全监管提供有效的技术支撑和理论参考。

关键词：双酚类化合物白酒接触塑料制品超高效液相色谱-串联质谱