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Journal of Environmental Sciences 2022年第4期34卷 412-421页

作者： Yan Liang Hui Rong Ling Liu Shaobing zhang xiuhui zhang Wenguo Xu School of Chemistry and Chemical Engineering Beijing Institute of TechnologyBeijing 100081China

Marine aerosols play an important role in the global aerosol system.In polluted coastal regions,ultra-fine particles have been recognized to be related to iodine-containing species and is more serious due to the impact of atmospheric pollutants.Many previous studies have identified iodine pentoxide(I_(2)O_(5),IP)to be the key species in new particles formation(NPF)in marine regions,but the role of IP in the polluted coastal atmosphere is far to be fully understood.Considering the high humidity and concentrations of pollutants in the polluted coastal regions,the gas-phase hydration of IP catalyzed by sulfuric acid(SA),nitric acid(NA),dimethylamine(DMA),and ammonia(A)have been investigated at DLPNO-CCSD(T)//ωB97 XD/aug-cc-pVTZ+aug-cc-pVTZ-PP with ECP28 MDF(for iodine)level of theory.The results show that the hydration of IP involves a significant energy barrier of 22.33 kcal/mol,while the pollutants SA,NA,DMA,and A all could catalyze the hydration of IP.Especially,with SA and DMA as catalysts,the hydration reactions of IP present extremely low barriers and high rate constants.It is suggested that IP is unstable under the catalysis of SA and DMA to generate iodic acid,which is the key component in NPF in marine regions.Thus,the catalytic hydration of IP is very likely to trigger the formation of iodine-containing particles.Our research provides a clear picture of the catalytic hydration of IP as well as theoretical guidance for NPF in the polluted coastal atmosphere.

关键词： Iodine oxides Iodine pentoxide Catalytic hydration Atmospheric pollutants Proton transfer

The missing base molecules in atmospheric acid-base nucleation

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National Science Review 2022年第10期9卷 196-208页

作者： Runlong Cai Rujing Yin Chao Yan Dongsen Yang Chenjuan Deng Lubna Dada Juha Kangasluoma Jenni Kontkanen Roope Halonen Yan Ma xiuhui zhang Pauli Paasonen Tuukka Pet?j? Veli-Matti Kerminen Yongchun Liu Federico Bianchi Jun Zheng Lin Wang Jiming Hao James N.Smith Neil M. Donahue Markku Kulmala Douglas R.Worsnop Jingkun Jiang Center for Atmospheric Particle Studies Carnegie Mellon University Department of Chemistry Carnegie Mellon University Aerodyne Research Inc. State Key Joint Laboratory of Environment Simulation and Pollution Control School of Environment Tsinghua University Institute for Atmospheric and Earth System Research/Physics Faculty of Science University of Helsinki Aerosol and Haze Laboratory Beijing Advanced Innovation Center for Soft Matter Science and Engineering Beijing University of Chemical Technology Collaborative Innovation Center of Atmospheric Environment and Equipment Technology Nanjing University of Information Science and Technology Laboratory of Atmospheric Chemistry Paul Scherrer Institute Center for Joint Quantum Studies and Department of Physics School of Science Tianjin University Key Laboratory of Cluster Science Ministry of Education of China School of Chemistry and Chemical Engineering Beijing Institute of Technology Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention (LAP3) Department of Environmental Science and Engineering Fudan University Chemistry Department University of California

Transformation of low-volatility gaseous precursors to new particles affects aerosol number concentration,cloud formation and hence the climate.The clustering of acid and base molecules is a major mechanism driving fast nucleation and initial growth of new particles in the atmosphere.However,the acid-base cluster composition,measured using state-of-the-art mass spectrometers,cannot explain the measured high formation rate of new particles.Here we present strong evidence for the existence of base molecules such as amines in the smallest atmospheric sulfuric acid clusters prior to their detection by mass spectrometers.We demonstrate that forming(H2SO4)1(amine)1is the rate-limiting step in atmospheric H2SO4-amine nucleation and the uptake of(H2SO4)1(amine)1is a major pathway for the initial growth of H2SO4clusters.The proposed mechanism is very consistent with measured new particle formation in urban Beijing,in which dimethylamine is the key base for H2SO4nucleation while other bases such as ammonia may contribute to the growth of larger clusters.Our findings further underline the fact that strong amines,even at low concentrations and when undetected in the smallest clusters,can be crucial to particle formation in the planetary boundary layer.

关键词： acid-base nucleation aerosol new particle formation polluted urban environment

单纯肱骨大结节骨折内固定术后失败原因分析及治疗策略

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中华手外科杂志 2024年第3期40卷 248-252页

作者：尹世豪张琳袁崔煦王秀会上海中医药大学上海201203 上海健康医学院附属周浦医院骨科上海201318

目的分析单纯肱骨大结节骨折行钢板螺钉内固定术的失败病例,总结内固定失败的原因并提出规避方法.方法回顾性分析自2019年1月至2022年6月在我院行切开复位钢板螺钉内固定治疗单纯肱骨大结节骨折患者59例,随访中内固定失效7例.记录患者... 详细信息

目的分析单纯肱骨大结节骨折行钢板螺钉内固定术的失败病例,总结内固定失败的原因并提出规避方法.方法回顾性分析自2019年1月至2022年6月在我院行切开复位钢板螺钉内固定治疗单纯肱骨大结节骨折患者59例,随访中内固定失效7例.记录患者的基线资料、围手术期指标;随访骨折愈合及功能恢复情况,记录相关并发症,术后1、3个月及末次随访用Neer评分、Constant-Murlery评分评估肩关节功能,视觉模拟评分(visual analogue scale,VAS)评估肩关节活动时疼痛情况.结果所有患者手术过程均顺利,平均手术时间为(65.5±17.8)min,平均出血量为(45.7±20.6)ml,平均切口长度为(6.4±3.5)cm.所有患者均获得随访,时间为12~30个月,平均(16.3±5.4)个月,随访过程中52例患者骨折愈合,平均愈合时间为(12.2±3.3)周.术后1、3个月以及末次随访Neer评分分别为(65.34±8.15)分、(75.33±9.36)分、(89.52±11.34)分;Constant-Murlery评分分别为(64.44±17.25)分、(75.62±18.44)分、(89.30±5.88)分;活动时VAS分别为(4.66±0.81)分、(2.34±1.50)分、(1.68±0.68)分.7例患者术后3个月内出现内固定失效,大结节骨块移位.3例患者行术后翻修,4例行外展架制动,随访过程中骨折均愈合.结论钢板螺钉内固定是单纯肱骨大结节骨折的有效治疗方法,钢板位置偏差、肩袖缝合欠佳、大结节骨块碎裂及术后制动不规范是内固定失效的主要原因,临床需注意规避.

关键词：肱骨骨折骨骨折固定术,内治疗结果内固定失效

温度对丙烷选择氧化催化剂Mo-V-Te-Ox催化性能的影响分析

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山西化工 2024年第2期44卷 107-109页

作者：张超超郑秀慧山东中海精细化工有限公司山东滨州256800

本文采用三氧化钼、水合硫酸氧钒和二氧化锑为主要原料,并添加氧化铈助剂,在不同温度下进行水热合成,并结合微波干燥和常规加热干燥,通过程序升温焙烧活化制备了复合氧化物Mo-V-Te-Ox催化剂。通过自建的气固相微型反应装置和气相色谱的... 详细信息

本文采用三氧化钼、水合硫酸氧钒和二氧化锑为主要原料,并添加氧化铈助剂,在不同温度下进行水热合成,并结合微波干燥和常规加热干燥,通过程序升温焙烧活化制备了复合氧化物Mo-V-Te-Ox催化剂。通过自建的气固相微型反应装置和气相色谱的联用对催化剂样品进行了活性评价。

关键词： Mo-V-Te-Ox催化剂水热合成微波加热法焙烧活化

基于BDNF/TrkB/ERK/CREB信号通路探究温笑散通过促进神经发生抗抑郁的作用机制

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中国实验方剂学杂志 2024年第8期30卷 100-108页

作者：张多郭秀慧栗俞程高云丽白明闫向丽许二平河南中医药大学中医药科学院河南省仲景方药现代研究重点实验室河南省豫药全产业链研发协同创新中心郑州450046

目的:探讨温笑散改善皮质酮诱导的小鼠抑郁样行为的作用机制。方法:雄性ICR小鼠随机分为正常组、模型组、帕罗西汀组(20 mg·kg^(-1))、温笑散低、高剂量组(3.27、6.54 g·kg^(-1)),正常组和模型组给予等体积的生理盐水,除正常组外其他... 详细信息

目的:探讨温笑散改善皮质酮诱导的小鼠抑郁样行为的作用机制。方法:雄性ICR小鼠随机分为正常组、模型组、帕罗西汀组(20 mg·kg^(-1))、温笑散低、高剂量组(3.27、6.54 g·kg^(-1)),正常组和模型组给予等体积的生理盐水,除正常组外其他各组在灌胃0.5 h后皮下注射皮质酮诱导抑郁模型。给药结束后检测小鼠抑郁样行为;酶联免疫吸附测定法(ELISA)检测血清皮质酮含量;尼氏染色观察海马神经元损伤情况;免疫荧光检测海马齿状回(DG)中双皮质素(DCX)表达;蛋白免疫印迹法检测海马组织中脑源性神经营养因子(BDNF)/酪氨酸激酶受体B(TrkB)/细胞外调节蛋白激酶(ERK)/环磷腺苷效应元件结合蛋白(CREB)信号通路相关蛋白表达。结果:与正常组比较,模型组小鼠糖水偏好率显著降低、悬尾不动时间显著增加(P<0.01),旷场中心区域的停留时间和运动总距离明显减少(P<0.05,P<0.01),血清皮质酮水平显著升高(P<0.01),海马DG区神经元体积明显缩小、细胞核染色加深,DG区的DCX表达减少,海马中BDNF、磷酸化(p)-TrkB、p-ERK、p-CREB蛋白表达明显降低(P<0.05,P<0.01)。与模型组比较,温笑散低剂量组糖水偏好、旷场、悬尾行为学指标明显改善(P<0.05,P<0.01),温笑散高剂量组糖水偏好、旷场行为学指标明显好转(P<0.05,P<0.01);温笑散给药组血清皮质酮水平均显著降低(P<0.01),海马DG区神经元结构和形态正常,细胞核明显、尼氏体丰富,DG区DCX的表达均升高,温笑散高剂量组海马中BDNF、p-TrkB、p-ERK、p-CREB蛋白表达明显升高(P<0.05,P<0.01)。结论:温笑散能改善皮质酮诱导的小鼠抑郁样行为,促进神经发生,其作用机制可能与激活BDNF/TrkB/ERK/CREB信号通路相关。

关键词：温笑散抑郁症脑源性神经营养因子(BDNF)/酪氨酸激酶受体B(TrkB)/细胞外调节蛋白激酶(ERK)/环磷腺苷效应元件结合蛋白(CREB) 神经发生

具备低电压穿越能力的自均压型混合直流变换器研究

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电力科学与技术学报 2024年第2期39卷 240-248页

作者：张伟滕婕罗世刚李秀慧白永利谭庄熙国网甘肃省电力公司经济技术研究院甘肃兰州730030 国网甘肃省电力公司甘肃兰州730030 湖南科技大学信息与电气工程学院湖南湘潭411100

输入串联输出并联型(input-series output-parallel,ISOP)直流变换器广泛应用于能源互联网中的直流电网场景,其关键问题在于解决系统模块间输入电压不均衡。为此,结合谐振型和移相型双有源桥(dual active bridge,DAB)变换器,提出一种具... 详细信息

输入串联输出并联型(input-series output-parallel,ISOP)直流变换器广泛应用于能源互联网中的直流电网场景,其关键问题在于解决系统模块间输入电压不均衡。为此,结合谐振型和移相型双有源桥(dual active bridge,DAB)变换器,提出一种具备自适应均压能力的混合型模块化ISOP型直流变换器,系统同时具备谐振型DAB的高效率和移相型DAB的灵活控制能力。通过在DAB源端的滞后桥臂中点增设无源的LC谐振支路,该谐振支路与相邻子模块的2个半桥模块共同构成非隔离型双有源半桥,以此来实现系统输入电压的自适应均衡。此外,提出一种低电压穿越(low voltage ride-through,LVRT)方法,在DAB前端连接电压调整模块,模块内部的高频变压器的副边串联电感,当系统输入输出侧发生电压跌落时具备故障穿越的能力,提高系统的暂态可控性。最后,在MATLAB/SIMULINK环境下搭建模型进行验证,可以证明系统的自适应均压性能及故障穿越方法的有效性。

关键词：输入串联输出并联型变换器双有源桥电压跌落自适应均压低压穿越

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Symplectic analysis for regulating wave propagation in a one-dimensional nonlinear graded metamaterial

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Applied Mathematics and Mechanics(English Edition) 2023年第5期44卷 745-758页

作者： Yunping ZHAO xiuhui HOU Kai zhang Zichen DENG Department of Applied Mathematics Northwestern Polytechnical UniversityXi’an 710072China School of Mechanics Civil Engineering and ArchitectureNorthwestern Polytechnical UniversityXi’an 710072China Ministry of Industry and Information Technology Key Laboratory of Dynamics and Control of Complex SystemsNorthwestern Polytechnical UniversityXi’an 710072China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116024China

An analytical method,called the symplectic mathematical method,is proposed to study the wave propagation in a spring-mass chain with gradient arranged local resonators and nonlinear ground springs.Combined with the linearized perturbation approach,the symplectic transform matrix for a unit cell of the weakly nonlinear graded metamaterial is derived,which only relies on the state vector.The results of the dispersion relation obtained with the symplectic mathematical method agree well with those achieved by the Bloch theory.It is shown that wider and lower frequency bandgaps are formed when the hardening nonlinearity and incident wave intensity increase.Subsequently,the displacement response and transmission performance of nonlinear graded metamaterials with finite length are studied.The dual tunable effects of nonlinearity and gradation on the wave propagation are explored under different excitation frequencies.For small excitation frequencies,the gradient parameter plays a dominant role compared with the nonlinearity.The reason is that the gradient tuning aims at the gradient arrangement of local resonators,which is limited by the critical value of the local resonator mass.In contrast,for larger excitation frequencies,the hardening nonlinearity is dominant and will contribute to the formation of a new bandgap.

关键词： symplectic mathematical method nonlinear graded metamaterial tunable bandgap

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乙唑螨腈与不同桶混助剂增效作用探索

农药 2024年第2期63卷 152-156页

作者：刘少武张俊龙赖先文宋玉泉常秀辉沈阳中化农药化工研发有限公司新农药创制与开发国家重点实验室农药国家工程研究中心沈阳110021 中化作物保护品有限公司上海200240

[目的]为探究乙唑螨腈与桶混助剂的混用效果,开展了乙唑螨腈与6种不同助剂的混配研究。[方法]采用喷雾法测定了乙唑螨腈与不同助剂混配的室内联合作用效力和田间防效。[结果]试验结果表明,乙唑螨腈分别与6种不同桶混助剂混配后,均表现... 详细信息

[目的]为探究乙唑螨腈与桶混助剂的混用效果,开展了乙唑螨腈与6种不同助剂的混配研究。[方法]采用喷雾法测定了乙唑螨腈与不同助剂混配的室内联合作用效力和田间防效。[结果]试验结果表明,乙唑螨腈分别与6种不同桶混助剂混配后,均表现出相加或增效作用。[结论]通过室内混配试验,推荐乙唑螨腈与有机硅类桶混助剂浩卓、功倍笑混配施用(1∶3),推荐乙唑螨腈与油类桶混助剂绿颖混配施用(1∶1);田间药效试验结果表明,乙唑螨腈与浩卓、功倍笑混配施用,速效性和持效性均优于单剂处理和对照药剂。

关键词：乙唑螨腈桶混助剂室内生物活性田间防效

新型乙烯基吡唑丙烯腈类化合物的合成及杀螨活性

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农药 2024年第5期63卷 325-329页

作者：张斌杨辉斌常秀辉宋玉泉李斌汪国庆沈阳科创化学品有限公司沈阳110144 沈阳中化农药化工研发有限公司新农药创制与开发国家重点实验室农药国家工程研究中心沈阳110021

[目的]为了发现结构新颖的杀螨活性化合物。[方法]以腈吡螨酯为先导化合物,在丙烯腈结构中引入乙烯基吡唑结构片断,设计合成了15个新型乙烯基吡唑丙烯腈类化合物,并对其进行杀螨活性测试。[结果]初步的室内生物活性测试结果表明:目标化... 详细信息

[目的]为了发现结构新颖的杀螨活性化合物。[方法]以腈吡螨酯为先导化合物,在丙烯腈结构中引入乙烯基吡唑结构片断,设计合成了15个新型乙烯基吡唑丙烯腈类化合物,并对其进行杀螨活性测试。[结果]初步的室内生物活性测试结果表明:目标化合物6a~6h均表现出较好的杀螨活性,在100 mg/L质量浓度下对朱砂叶螨致死率均≥99%。其中化合物6 g表现最佳,在10 mg/L下对朱砂叶螨致死率仍为88%。[结论]当羟基上的H被烷基羰基、烷氧基羰基取代时,化合物具有较好的杀螨活性。

关键词：乙烯基吡唑丙烯腈合成杀螨活性

TPE-H2MWD:an exact thumbnail preserving encryption scheme with hidden Markov model and weighted diffusion

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信息与电子工程前沿:英文版 2023年第8期24卷 1169-1180页

作者： Xiuli CHAI xiuhui CHEN Yakun MA Fang ZUO Zhihua GAN Yushu zhang School of Artificial Intelligence Henan Engineering Research Center for Industrial Internet of ThingsHenan UniversityZhengzhou450046China Henan Key Laboratory of Cyberspace Situation Awareness Zhengzhou450001China School of Software Intelligent Data Processing Engineering Research Center of Henan ProvinceInstitute of Intelligent Network SystemHenan UniversityKaifeng475004China College of Computer Science and Technology Nanjing University of Aeronautics and AstronauticsNanjing211106China

With the substantial increase in image transmission,the demand for image security is increasing.Noise-like images can be obtained by conventional encryption schemes,and although the security of the images can be guaranteed,the noise-like images cannot be directly previewed and retrieved.Based on the rank-then-encipher method,some researchers have designed a three-pixel exact thumbnail preserving encryption(TPE2)scheme,which can be applied to balance the security and availability of images,but this scheme has low encryption efficiency.In this paper,we introduce an efficient exact thumbnail preserving encryption scheme.First,blocking and bit-plane decomposition operations are performed on the plaintext image.The zigzag scrambling model is used to change the bit positions in the lower four bit planes.Subsequently,an operation is devised to permute the higher four bit planes,which is an extended application of the hidden Markov model.Finally,according to the difference in bit weights in each bit plane,a bit-level weighted diffusion rule is established to generate an encrypted image and still maintain the same sum of pixels within the block.Simulation results show that the proposed scheme improves the encryption efficiency and can guarantee the availability of images while protecting their privacy.

关键词： Hidden Markov model Weighted diffusion Balance between usability and privacy Image encryption