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β-环糊精接枝壳聚糖对铅离子的吸附研究

江西化工 2024年第1期40卷 104-108页

作者：李海丰刘海江廖绍群万志勇黄丽华新余市生态环境污染防治中心江西新余338000 江门生态环境监测站广东江门529000

环糊精接枝壳聚糖(CS-CD)分子中含有-OH及大量游离-NH2,导致其可借离子键,也可借氢键形成具有类似网状结构的笼形分子,从而对二价铅离子发挥稳定的配位作用。通过实验,研究了pH、β-环糊精接枝壳聚糖投加量、Pb^(2+)的初始浓度等因素对... 详细信息

环糊精接枝壳聚糖(CS-CD)分子中含有-OH及大量游离-NH2,导致其可借离子键,也可借氢键形成具有类似网状结构的笼形分子,从而对二价铅离子发挥稳定的配位作用。通过实验,研究了pH、β-环糊精接枝壳聚糖投加量、Pb^(2+)的初始浓度等因素对β-环糊精接枝壳聚糖吸附去除水中Pb^(2+)的效果的影响。结果表明,溶液在pH=6时对Pb^(2+)的吸附效果最好;增大反应物接触的比表面积,有利于吸附;初始浓度的增加相当于增加了反应物的量,有利于吸附反应的进行;在一定温度范围内,升温有利于吸附。实验还表明,β-环糊精接枝壳聚糖对Pb^(2+)的吸附更符合准二级动力学方程;吸附反应自由能变<0kJ/mol,说明反应是自发进行的;XPS分析结果进一步表明该反应属于化学吸附过程。

关键词：吸附动力学等温线化学吸附

FORMATION AND INFLUENCING FACTORS OF FREE SURFACE VORTEX IN A BARREL WITH A CENTRAL ORIFICE AT BOTTOM

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Journal of Hydrodynamics 2009年第2期21卷 238-244页

Based on the Navier-Stokes equations with considering the effect of the Coriolis force, the finite volume method was employed to discretize the governing equations, the SIMPLE method was adopted to solve the discretized equations, and the flow field in a barrel with an outlet at the center of the bottom was simulated. The numerical results agree well with the experimental data. From the Lagrangian, the relations among the acceleration, the Coriolis force and the viscosity force were analyzed. The results show that the Coriolis force is the major factor that causes the formation of the vortex. The flow fields in the flume under different incoming flow conditions were numerically simulated using the software Fluent. The numerical simulations show good agreement with the experiments for the shape and position of the vortex.

关键词： free surface vortex Coriolis force numerical simulation

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钙处理工艺对钢中夹杂物的影响分析及应用

云南冶金 2024年第1期53卷 178-186页

作者：王念欣曾晖王成镇李海峰张亮山东钢铁股份有限公司山东济南250101

针对钙处理工艺对钢水洁净度影响的问题,使用平衡相图进行不同钙含量下生成的夹杂物类型、含量对比分析,结果表明:随着钢中钙含量升高,钢中氧化物夹杂数密度从钙含量1×10^(-6)时的0.52个/mm^(2)降至0.4个/mm^(2);钢中大尺寸夹杂数密度... 详细信息

针对钙处理工艺对钢水洁净度影响的问题,使用平衡相图进行不同钙含量下生成的夹杂物类型、含量对比分析,结果表明:随着钢中钙含量升高,钢中氧化物夹杂数密度从钙含量1×10^(-6)时的0.52个/mm^(2)降至0.4个/mm^(2);钢中大尺寸夹杂数密度先上升后下降,从钙含量1×10^(-6)时的0.005个/mm降至0.004个/mm^(2);同时随着钢中氧含量的增加,钢中溶解钙含量在3~4×10^(-6),变化不大,钙的活度明显受到抑制。

关键词：钙处理夹杂物洁净度 Al_(2)O_(3)含量

老年性聋患者认知功能对言语识别能力的影响研究

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中国听力语言康复科学杂志 2024年第2期22卷 172-176页

作者：任燕汪婷周嵌李海峰黄治物上海交通大学医学院附属第九人民医院耳鼻咽喉头颈外科/上海市耳鼻疾病转化医学重点实验室/上海交通大学医学院耳科学研究所/上海市儿童听力障碍诊治中心上海200011 上海中医药大学康复医学院上海201203

目的通过评估老年性聋患者的认知功能和言语识别能力,分析认知功能对言语识别能力的影响,为完善老年性聋的康复干预方案提供依据。方法选取106例确诊为老年性聋的患者,使用蒙特利尔认知评估量表(montreal cognitive assessment,MoCA)评... 详细信息

目的通过评估老年性聋患者的认知功能和言语识别能力,分析认知功能对言语识别能力的影响,为完善老年性聋的康复干预方案提供依据。方法选取106例确诊为老年性聋的患者,使用蒙特利尔认知评估量表(montreal cognitive assessment,MoCA)评估受试者的认知功能,并对其听觉言语功能进行测试。根据量表分数把所有受试者分为认知正常组和认知障碍组各53例,比较两组间言语识别功能的差异,分析认知功能对其言语识别能力的影响。结果(1)两组MoCA得分在视空间与执行能力、注意、语言、抽象、延迟回忆、定向力等认知域存在显著差异(P<0.05);(2)认知正常组的最大言语识别率显著高于认知障碍组(P<0.05);(3)所有受试者MoCA得分与最大言语识别率呈正相关(r=0.269,P<0.05);(4)不同听力损失组之间的最大言语识别率存在显著差异(P<0.05)。结论认知功能会对老年性聋患者的言语识别能力产生影响,随着认知功能的降低,言语识别能力也变弱。

关键词：老年性聋认知功能言语识别能力

Supermassive black holes triggered by QCD axion bubbles

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Communications in Theoretical Physics 2024年第5期76卷 134-139页

作者： hai-Jun li Ying-Quan Peng Wei Chao Yu-feng Zhou Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of SciencesBeijing 100190China Center for Advanced Quantum Studies Department of PhysicsBeijing Normal UniversityBeijing 100875China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100049China School of Fundamental Physics and Mathematical Sciences Hangzhou Institute for Advanced StudyUCASHangzhou 310024China International Centre for Theoretical Physics Asia-Pacific Beijing/HangzhouChina

Supermassive black holes(SMBHs)are ubiquitous in the center of galaxies,although the origin of their massive seeds is still *** this paper,we investigate the formation of SMBHs from the quantum chromodynamics(QCD)axion *** this case,primordial black holes(PBHs)are considered as the seeds of SMBHs,which are generated from the QCD axion bubbles due to an explicit Peccei–Quinn(PQ)symmetry breaking after *** QCD axion bubbles are formed when the QCD axion starts to oscillate during the QCD phase *** consider a general case in which the axion bubbles are formed with the bubble effective angle θ_(eff)∈(0,π],leading to the minimum PBH mass∼■(10^(4)−10^(7))M⊙for the axion decay constant f_(a)∼■(10^(16))*** PBHs at this mass region may account for the seeds of SMBHs.

关键词： supermassive black holes primordial black holes quantum chromodynamics axion

基于无线传感网络的电气设备温度智能监测系统

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自动化技术与应用 2024年第1期43卷 56-60页

作者：李海峰崔积华朱林林阳薇国网黑龙江省电力有限公司检修公司黑龙江哈尔滨150036 哈尔滨电力职业技术学院黑龙江哈尔滨150030

为防止由于温度异常造成的电气设备故障,提出基于无线传感网络的电气设备温度智能监测系统。利用无线传感网络及ZigBee网络采集节点,低功耗采集并传输电气设备温度信息到监测中心,利用DNN网络构建电气设备温度监测智能分析模型,实现电... 详细信息

为防止由于温度异常造成的电气设备故障,提出基于无线传感网络的电气设备温度智能监测系统。利用无线传感网络及ZigBee网络采集节点,低功耗采集并传输电气设备温度信息到监测中心,利用DNN网络构建电气设备温度监测智能分析模型,实现电气设备温度的实时输出与处理。实验表明,该系统的信息传输功耗较低;可精准监测电气设备温度,可通过界面形式展现监测结果。

关键词：无线传感网络电气设备温度智能监测汇聚节点

High-performance magnesium/sodium hybrid ion battery based on sodium vanadate oxide for reversible storage of Na^(+)and Mg^(2+)

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Journal of Energy Chemistry 2024年第9期96卷 79-88页

作者： Xiaoke Wang Titi li Xixi Zhang Yaxin Wang Hongfei li hai-feng li Gang Zhao Cuiping Han Institute of Applied Physics and Materials Engineering University of MacaoAvenida da UniversidadeTaipaMacao 999078China School of Physics and Technology University of JinanJinan 250022ShandongChina Songshan Lake Materials Laboratory Dongguan 523808GuangdongChina Faculty of Materials Science and Energy Engineering Shenzhen University of Advanced TechnologyShenzhen 518055GuangdongChina Institute of Technology for Carbon Neutrality Shenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhen 518055GuangdongChina

Magnesium ion batteries(MIBs)are a potential field for the energy storage of the future but are restricted by insufficient rate capability and rapid capacity ***-sodium hybrid ion batteries(MSHBs)are an effective way to address these ***,we report a new type of MSHBs that use layered sodium vanadate((Na,Mn)V_(8)O_(20)·5H_(2)O,Mn-NVO)cathodes coupled with an organic 3,4,9,10-perylenetetracarboxylic diimide(PTCDI)anode in Mg^(2+)/Na^(+)hybrid *** electrochemical cycling,Mg^(2+)and Na^(+)co-participate in the cathode reactions,and the introduction of Na^(+)promotes the structural stability of the Mn-NVO cathode,as cleared by several ex-situ ***,the Mn-NVO cathode presents great specific capacity(249.9 mA h g^(−1)at 300 mA g^(−1))and cycling(1500 cycles at 1500 mA g^(−1))in the Mg^(2+)/Na^(+)hybrid ***,full battery displays long lifespan with 10,000 cycles at 1000 mA g^(−1).The rate performance and cycling stability of MSHBs have been improved by an economical and scalable method,and the mechanism for these improvements is discussed.

关键词： Aqueous battery Hybrid ion battery Mg^(2+)/Na^(+)co-intercalation High-rate performance Organic-water hybrid electrolyte

Effect of microalloying on wettability and interface characteristics of Zr-based bulk metallic glasses with W substrate

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China Foundry 2024年第4期21卷 352-359页

作者： Zhen Zhang lin-na feng Jin-he Wang Zheng-kun li Hua-meng Fu Hong li Zheng-wang Zhu hai-feng Zhang School of Materials Science and Engineering Shenyang University of TechnologyShenyang 110870China Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaShenyang 110016China School of Metallurgy Northeastern UniversityShenyang 110004China

The infiltration casting method is widely employed for the preparation of ex-situ composite ***,the production of composite materials using this method must necessitates a comprehensive understanding of the wettability and interface characteristics between the reinforcing phase and the bulk metallic glasses(BMGs).This work optimized the composition of Zr-based BMGs through microalloying methods,resulting in a new set of Zr-based BMGs with excellent glass-forming *** experiments between the Zr-based BMGs melts and W substrates were conducted using the traditional sessile drop method,and the interfaces were characterized utilizing a scanning electron microscope(SEM)equipped with energy dispersive X-ray spectroscopy(EDS).The work demonstrates that the microalloying method substantially enhances the wettability of the Zr-based BMGs ***,the incorporation of Nb element impedes the formation of W-Zr phases,but the introduction of Nb element does not alter the extent of interdiffusion between the constituent elements of the amorphous matrix and W element,indicating that the influence of Nb element on the diffusion of individual elements is minute.

关键词： Zr-based BMGs infiltration casting method wettability interface characteristics W-Zr phases

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并联三电平光伏并网逆变器中点电压控制策略

电力电子技术 2024年第2期58卷 68-70,114页

作者：史可鉴代子阔李海峰王智博国网辽宁省电力有限公司电力科学研究院辽宁沈阳110000 国网辽宁省电力有限公司辽宁沈阳110000

针对光伏并网三电平逆变器并联系统的中点电位控制问题,传统的双调制波法无法保证开关周期内平均中点电流始终为零,从而无法有效消除中点电压的低频波动。为此,提出了一种基于改进双调制波法的中点电压控制策略。该策略通过对传统双调... 详细信息

针对光伏并网三电平逆变器并联系统的中点电位控制问题,传统的双调制波法无法保证开关周期内平均中点电流始终为零,从而无法有效消除中点电压的低频波动。为此,提出了一种基于改进双调制波法的中点电压控制策略。该策略通过对传统双调制法重构的调制波进行修正,在不影响并联系统输出电压的前提下保证平均中点电流始终为零,不仅可以实现中点电压的平衡控制而且具有良好的动态性能。实验结果验证了所提策略的可行性和有效性。

关键词：光伏并网三电平逆变器并联系统双调制波法