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空腔结构吸声器的吸声系数计算方法的研究 被引量:19
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作者 王仁乾 《声学学报》 EI CSCD 北大核心 2004年第5期393-397,共5页
探讨计算空腔结构吸声器吸声系数的方法。以粘弹体能量守恒方程为基础导出吸声器各层媒质的表达式,用声波在分层吸收媒质中传播模型计算能量吸收系数。用所导出的等效密度、弹性模量表达式和文献1[声学学报,1965;2(4):192-197]、文献2[... 探讨计算空腔结构吸声器吸声系数的方法。以粘弹体能量守恒方程为基础导出吸声器各层媒质的表达式,用声波在分层吸收媒质中传播模型计算能量吸收系数。用所导出的等效密度、弹性模量表达式和文献1[声学学报,1965;2(4):192-197]、文献2[同济大学学报, 1979(1):96-104]所给的等效参数,分别计算了尖劈吸声器和空腔结构的尖劈吸声器的吸声系数,比较表明对于前者三种方法都有效,对于后者本文的结果与实测吸声系数曲线较符合,另两文与实验相差较大;又用本方法分别计算了平板吸声器含空腔及空腔结构变化时的吸声系数,所得结果合理地反映了空腔结构对吸声性能的影响;对原空腔结构吸声器的吸声系数模拟结果作了实验验证,表明计算值和测量结果基本相符。结果表明用本文所给等效参量表达式和声波在分层吸收媒质中传播模型,近似计算空腔结构吸声器的吸声系数是可行的。 展开更多
关键词 空腔结构 吸声器 吸声系数 粘弹体能量守恒方程 等效密度
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Technical Perspective of Carbon Capture,Utilization,and Storage 被引量:16
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作者 Qingyang Lin Xiao Zhang +2 位作者 Tao Wang Chenghang Zheng Xiang Gao 《Engineering》 SCIE EI CAS 2022年第7期27-32,共6页
Carbon dioxide(CO_(2))is the primary greenhouse gas contributing to anthropogenic climate change which is associated with human activities.The majority of CO_(2) emissions are results of the burning of fossil fuels fo... Carbon dioxide(CO_(2))is the primary greenhouse gas contributing to anthropogenic climate change which is associated with human activities.The majority of CO_(2) emissions are results of the burning of fossil fuels for energy,as well as industrial processes such as steel and cement production.Carbon capture,utilization,and storage(CCUS)is a sustainable technology promising in terms of reducing CO_(2) emissions that would otherwise contribute to climate change.From this perspective,the discussion on carbon capture focuses on chemical absorption technology,primarily due to its commercialization potential.The CO_(2) absorptive capacity and absorption rate of various chemical solvents have been summarized.The carbon utilization focuses on electrochemical conversion routes converting CO_(2) into potentially valuable chemicals which have received particular attention in recent years.The Faradaic conversion efficiencies for various CO_(2) reduction products are used to describe efficiency improvements.For carbon storage,successful deployment relies on a better understanding of fluid mechanics,geomechanics,and reactive transport,which are discussed in details. 展开更多
关键词 CCUS Carbon capture Carbon utilization Carbon storage Chemical absorption Electrochemical conversion Storage mechanism
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天然富硒土壤上三种蔬菜对硒的吸收与转化差异 被引量:13
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作者 张青 王煌平 +3 位作者 孔庆波 章赞德 栗方亮 罗涛 《植物营养与肥料学报》 CAS CSCD 北大核心 2019年第10期1727-1736,共10页
【目的】研究对硒(Se)不同敏感性蔬菜对天然富硒土(Se≥0.4 mg/kg)中硒的吸收和转化差异,为富硒土壤生产富硒蔬菜提供理论与技术指导。【方法】以大蒜、芥菜和菠菜三种蔬菜为试验材料,在全硒含量为0.29、0.58、0.98、2.07 mg/kg的四种... 【目的】研究对硒(Se)不同敏感性蔬菜对天然富硒土(Se≥0.4 mg/kg)中硒的吸收和转化差异,为富硒土壤生产富硒蔬菜提供理论与技术指导。【方法】以大蒜、芥菜和菠菜三种蔬菜为试验材料,在全硒含量为0.29、0.58、0.98、2.07 mg/kg的四种土壤上进行了盆栽试验(依次标记为Se0.29、Se0.58、Se0.98、Se2.07),并测定四种土壤中不同形态硒的含量。芥菜和菠菜于生长40 d、53 d、68 d和82 d后取样,测定蔬菜可食部分硒含量;于生长97 d后收获,分为根部和地上部。大蒜于生长42 d、68 d、82 d、120 d后取样,测定地上部硒含量;于生长165 d后收获,分为根部、鳞茎和叶。测定供试蔬菜总硒含量、有机硒含量,计算不同硒含量土壤上蔬菜对硒的吸收和转化系数。【结果】三种蔬菜中芥菜的生长对土壤硒最为敏感,芥菜可食部位生物量鲜重以Se0.29处理最高,菠菜和大蒜均以Se0.58处理最高,与Se2.07处理均达显著差异。三种蔬菜地上部硒含量在整个生育期总体呈现增加的趋势,不同生育期均表现为大蒜>芥菜>菠菜。收获期三种蔬菜各部位的硒含量随着土壤硒含量(0.29~2.07 mg/kg)的增加而增加,表现为Se2.07> Se0.98> Se0.58> Se0.29,Se2.07处理的菠菜地上部和地下部硒含量分别是其Se0.29处理的8.63倍和7.10倍,芥菜是12.25倍和23.29倍,Se2.07处理大蒜鳞茎和叶部硒含量是Se0.29处理的39.92倍和4.90倍;可食部位硒含量为大蒜(7.25~289μg/kg)>芥菜(1.22~14.9μg/kg)>菠菜(0.73~6.30μg/kg),均表现为地下部>地上部,Se2.07处理菠菜根部硒含量是茎叶的4.80倍,芥菜是12.06倍,大蒜是8.22倍。在富硒土壤Se0.98和Se2.07处理条件下,大蒜和芥菜能从土壤中富集硒,吸收系数是菠菜的3.06~8.47倍和1.58~5.8倍,均达到了富硒蔬菜标准(≥0.01 mg/kg)。三种蔬菜可食部位有机硒含量占总硒比例为73.5%~84.7%,并随土壤硒含量的增加而增加,其中Se2.07与Se0.29处理差异显著;蔬� 展开更多
关键词 蔬菜 富硒土壤 吸收 转化 有机硒
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硒对生菜生长、品质、养分吸收和硒转化率的影响 被引量:12
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作者 袁伟玲 刘志雄 +2 位作者 吴金平 殷红清 陈磊夫 《华北农学报》 CSCD 北大核心 2020年第S01期189-194,共6页
研究叶面喷施不同浓度外源硒对生菜生长特性、品质、养分吸收和硒含量的影响,为富硒蔬菜生产合理施硒提供理论依据和技术指导。以芳妮为试验材料,采用大田试验,设置6个处理(0,0.5,1.0,1.5,2.0,2.5 mg/L Se),于生菜定植后第15,25天叶面喷... 研究叶面喷施不同浓度外源硒对生菜生长特性、品质、养分吸收和硒含量的影响,为富硒蔬菜生产合理施硒提供理论依据和技术指导。以芳妮为试验材料,采用大田试验,设置6个处理(0,0.5,1.0,1.5,2.0,2.5 mg/L Se),于生菜定植后第15,25天叶面喷施,研究硒对植株生长、品质、养分含量和硒转化率的影响。结果表明,当硒浓度小于1.5 mg/L时,促进生菜的生长,产量增加;当硒浓度大于2.0 mg/L,抑制了生菜的生长,产量降低。叶面喷施外源硒增加了生菜地上部可溶性总糖和总酚含量;低浓度外源硒(Se≤1.5 mg/L)增加了粗纤维和维生素C含量,而高浓度硒(Se≥2.0 mg/L)降低了其含量;类黄酮表现出先下降后升高的趋势。生菜地上部分N、Ca、Zn含量随着喷施外源硒浓度的增加表现出先升后降的趋势;随喷施硒浓度的增加,Mg含量增加,而P、K、S含量表现出下降趋势;低浓度硒降低了生菜地上部Fe元素的含量,但随着喷施硒浓度的增加地上部的含量明显增加。生菜地下部N、S元素的含量随叶面喷施浓度的增加而增加;P、Ca、Mg、Fe、Zn含量表现出下降趋势;适量硒浓度(Se≤1.5 mg/L)增加生菜地下部K元素的含量,高浓度则降低了其含量。生菜地上部硒的含量以有机态硒为主,有机硒转化率均在80%以上。因此,喷施硒浓度为1.5 mg/L对生菜产量提高、品质改善和养分吸收具有显著促进作用,也有利于富硒功能蔬菜的生产。 展开更多
关键词 生菜 亚硒酸盐 生长 养分吸收 硒转化率
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n-ZnO:Al/i-ZnO/n-CdS/p-Cu_2ZnSnS_4太阳能电池光伏特性的分析 被引量:8
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作者 许佳雄 姚若河 《物理学报》 SCIE EI CAS CSCD 北大核心 2012年第18期453-460,共8页
具有高光吸收系数的半导体Cu_2ZnSnS_4(CZTS)薄膜是一种新型太阳能电池材料.本文对n-ZnO:Al/i-ZnO/n-CdS/p-CZTS结构的CZTS薄膜太阳能电池进行分析,讨论CZTS薄膜的掺杂浓度、厚度、缺陷态和CdS薄膜的掺杂浓度、厚度对太阳能电池转换效... 具有高光吸收系数的半导体Cu_2ZnSnS_4(CZTS)薄膜是一种新型太阳能电池材料.本文对n-ZnO:Al/i-ZnO/n-CdS/p-CZTS结构的CZTS薄膜太阳能电池进行分析,讨论CZTS薄膜的掺杂浓度、厚度、缺陷态和CdS薄膜的掺杂浓度、厚度对太阳能电池转换效率的影响以及太阳能电池的温度特性.分析表明,CZTS薄膜作为太阳能电池的主要光吸收层,CZTS薄膜的掺杂浓度和厚度的取值对太阳能电池的转换效率有显著影响,CZTS薄膜结构缺陷态的存在会导致太阳能电池性能的下降.CdS缓冲层的掺杂浓度、厚度对太阳能电池光伏特性的影响较小.经结构参数优化得到的n-ZnO:Al/i-ZnO/n-CdS/p-CZTS薄膜太阳能电池的最佳光伏特性为开路电压1.127 V、短路电流密度27.39 mA/cm^2、填充因子87.5%、转换效率27.02%,转换效率温度系数为-0.14%/K. 展开更多
关键词 Cu2ZnSnS4薄膜太阳能电池 光吸收 转换效率
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Improvement on Mixograph test through water addition and parameter conversions 被引量:6
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作者 SUN Jia-zhu YANG Wen-long +6 位作者 LIU Dong-cheng ZHAO Jun-tao LUO Guang-bin LI Xin LIU Yan-jun GU O Jin-kao ZHANG Ai-min 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2015年第9期1715-1722,共8页
To improve Mixograph testing effect, Farinograph measurements were adopted as a quality standard and changes in water absorption and parameter conversion in Mixograph test were explored. Comparative study showed that ... To improve Mixograph testing effect, Farinograph measurements were adopted as a quality standard and changes in water absorption and parameter conversion in Mixograph test were explored. Comparative study showed that increasing water absorption to about 73% and converting original parameters to compound parameters in Mixograph tests signiifcantly increased their predictive power for lfour quality. These efforts also enabled the adoption of ifxed water addition level in Mixograph test and simpliifed the test procedure signiifcantly. With the success in parameter conversions, Mixograph test results were successful y described by Farinograph parameters, which al ow breeders to compare and exchange test results easily. Al these changes optimized the ofifcial method of Mixograph test with simpliifed procedure and enhanced reliability and made the Mixograph being the superior tool for quality assessment in wheat-breeding programs. 展开更多
关键词 MIXOGRAPH water absorption compound parameter constant water addition parameter conversion
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Multifunctional WSe_(2)/Co_(3)C composite for efficient electromagnetic absorption, EMI shielding, and energy conversion 被引量:3
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作者 Yuhang Zhu Tingting Liu +1 位作者 Lin Li Maosheng Cao 《Nano Research》 SCIE EI CSCD 2024年第3期1655-1665,共11页
Currently,as the electromagnetic(EM)environment becomes increasingly complex,single-function EM materials can hardly resist the increasing electromagnetic interference(EMI),and there is an urgent need to develop multi... Currently,as the electromagnetic(EM)environment becomes increasingly complex,single-function EM materials can hardly resist the increasing electromagnetic interference(EMI),and there is an urgent need to develop multifunctional EM materials.In this work,multifunctional WSe_(2)/Co_(3)C was prepared by simple hydrothermal methods.Its dielectric performance and EM response were investigated.Efficient absorption,shielding performance,and energy conversion devices were customized.By tailoring the loading content,WSe_(2)/Co_(3)C can switch between EM absorption and EMI shielding.The maximum shielding effectiveness(SE)of WSe_(2)/Co_(3)C reached 36 dB,and high reflection loss(RL)of-60.28 dB and wide effective absorption bandwidth(EAB)of 6.16 GHz can be obtained at low thickness.The multiple EM attenuation mechanisms brought by the combination of two-dimensional(2D)WSe_(2) and magnetic Co_(3)C are considered to be the main reason for the enhanced EM attenuation ability.The WSe_(2)/Co_(3)C composite provides a viable candidate for developing multifunctional EM materials in 2–18 GHz. 展开更多
关键词 WSe_(2) Co_(3)C electromagnetic property microwave absorption electromagnetic interference shielding energy conversion
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In situ studies of energy-related electrochemical reactions using Raman and X-ray absorption spectroscopy 被引量:6
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作者 Heng‐Quan Chen Lie Zou +4 位作者 Di‐Ye Wei Ling‐Ling Zheng Yuan‐Fei Wu Hua Zhang Jian‐Feng Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第1期33-46,共14页
Electrochemical energy conversion technologies involving processes such as water splitting and O_(2)/CO_(2) reduction,provide promising solutions for addressing global energy scarcity and minimizing adverse environmen... Electrochemical energy conversion technologies involving processes such as water splitting and O_(2)/CO_(2) reduction,provide promising solutions for addressing global energy scarcity and minimizing adverse environmental impact.However,due to a lack of an in-depth understanding of the reaction mechanisms and the nature of the active sites,further advancement of these techniques has been limited by the development of efficient and robust catalysts.Therefore,in situ characterization of these electrocatalytic processes under working conditions is essential.In this review,recent applications of in situ Raman spectroscopy and X-ray absorption spectroscopy for various nano-and single-atom catalysts in energy-related reactions are summarized.Notable cases are highlighted,including the capture of oxygen-containing intermediate species formed during the reduction of oxygen and oxidation of hydrogen,and the detection of catalyst structural transformations occurring with the change in potential during the evolution of oxygen and reduction of CO_(2).Finally,the challenges and outlook for advancing in situ spectroscopic technologies to gain a deeper fundamental understanding of these energy-related electrocatalytic processes are discussed. 展开更多
关键词 Raman spectroscopy X-ray absorption spectroscopy In situ characterization ELECTROCATALYSIS Energy conversion and storage
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Solution-processed D-A-π-A-D radicals for highly efficient photothermal conversion 被引量:1
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作者 Jiaxing Huang Zejun Wang +1 位作者 Weiya Zhu Yuan Li 《Aggregate》 EI CAS 2024年第1期398-408,共11页
Organic donor-acceptor semiconductors exhibit great potential in photothermal conversion.However,it is still challenging to achieve pure organic materials with broad absorption comparable with inorganic materials such... Organic donor-acceptor semiconductors exhibit great potential in photothermal conversion.However,it is still challenging to achieve pure organic materials with broad absorption comparable with inorganic materials such as graphene.Herein,two D-AD type DPA-BT-O4 and NDI-TPA-O4 and three D-A-π-A-D type Th-O4,Th2-O4,and IDT-O4 were readily prepared via two high-yield steps and simple air oxidization.The stability can be attributed to their multiple resonance structures based on the aromatic nitric acid radical mechanism.Compared with the D-A-D radicals,the conjugation extension of the D-A-π-A-D radicals endows them with a narrowed band gap and broad absorption in powder.Interestingly,the IDT-O4 powder with aggregation-induced radical effect exhibits broad absorption between 300 and 2500 nm,which is comparable with graphene and other inorganic materials.Under irradiation of 0.9 W/cm^(2)(808 nm),the temperature of IDT-O4 powder rises to 250℃within 60 s.The water evaporation conversion efficiency of 94.38%and an evaporation rate of 1.365 kg/m^(2)h^(−1)under one sun illumination were achieved.IDT-O4 stands as one of the most efficient photothermal conversion materials among pure organic materials via a rational design strategy. 展开更多
关键词 DONOR-ACCEPTOR near-infrared absorption open-shell radicals photothermal conversion seawater desalination
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TFE-E181双吸收热变换器热力过程分析 被引量:4
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作者 赵宗昌 周方伟 李凇平 《大连理工大学学报》 EI CAS CSCD 北大核心 2003年第5期604-608,共5页
以TFE-E181(三氟乙醇-四甘醇二甲醚)为工作流体,采用一种新的溶液循环方式研究了大温升、双吸收式热变换器的热力循环性能.计算结果表明,与传统循环相比,该双吸收热变换器不仅具有更宽的操作范围,而且具有更高的性能系数和灯用效率,发... 以TFE-E181(三氟乙醇-四甘醇二甲醚)为工作流体,采用一种新的溶液循环方式研究了大温升、双吸收式热变换器的热力循环性能.计算结果表明,与传统循环相比,该双吸收热变换器不仅具有更宽的操作范围,而且具有更高的性能系数和灯用效率,发生器产生的单位质量工质在吸收器中输出的热量和输出的灯用也更高,其提高的幅度随吸收温度的增高而变大.当温升为60℃时,其性能系数为0.22,灯用效率为0.45,单位质量TFE的制热量为130kJ/kg.同样条件下,以H2O-LiBr为工质对的双吸收式热变换器,其性能系数为0.32,灯用效率为0.66,单位质量的工质水的制热量为1250kJ/kg.此外,还分析了吸收温度、吸收蒸发温度对系统的性能系数、灯用效率、循环倍率、分流比的影响规律. 展开更多
关键词 TFE—E181双吸收热变换器 热力过程 溶液循环 热力循环性能 性能系数 YONG效率
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银纳米链状材料的制备及近红外吸收性质 被引量:4
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作者 刘钟馨 宋宏伟 《发光学报》 EI CAS CSCD 北大核心 2008年第6期1067-1070,共4页
报道了利用水/油相界面反应,采用湿化学法合成银纳米链状材料的方法,并对这种材料的近红外吸收性质和光热转换性质进行了研究。TEM分析表明,银纳米材料为链状结构,直径约为50nm,长度分布范围较宽,从几十纳米至几百纳米。这种材料具有强... 报道了利用水/油相界面反应,采用湿化学法合成银纳米链状材料的方法,并对这种材料的近红外吸收性质和光热转换性质进行了研究。TEM分析表明,银纳米材料为链状结构,直径约为50nm,长度分布范围较宽,从几十纳米至几百纳米。这种材料具有强的近红外吸收特性,随着还原剂加入量的增加,吸收带逐渐展宽(800~1300nm),而且平坦。这种材料具有优异光热转换性质,一经808nm激光照射,温度迅速提高。该材料优异的近红外吸收和光热转换性质,使其在红外断层成像和近红外热疗等领域具有广阔的应用前景。 展开更多
关键词 银纳米链 SPR红外吸收 光热转换
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金属配位(螯合)型离子液体在二氧化碳吸收和转化中的研究进展 被引量:5
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作者 许映杰 舒荷刚 +1 位作者 刘佳佳 付雪 《科学通报》 EI CAS CSCD 北大核心 2021年第7期728-738,共11页
金属配位型离子液体(ionic liquids, ILs)是一类由金属离子与有机或无机配体通过配位作用形成的低温熔盐.其中,当金属离子与配体具有多齿配位点时,将其称为金属螯合型ILs.目前,金属配位(螯合)型ILs已经被广泛用于气体吸收和有机催化等领... 金属配位型离子液体(ionic liquids, ILs)是一类由金属离子与有机或无机配体通过配位作用形成的低温熔盐.其中,当金属离子与配体具有多齿配位点时,将其称为金属螯合型ILs.目前,金属配位(螯合)型ILs已经被广泛用于气体吸收和有机催化等领域,显示出了优异的性能.本文首先对近年来金属阴离子配位型ILs和金属阳离子螯合型ILs在二氧化碳(CO_(2))吸收中的应用进行综述,重点讨论了金属离子、配体和阴离子种类对CO_(2)吸收性能的影响;其次,总结了金属阴离子配位型ILs、金属阳离子配位型ILs、金属阴阳离子配位型ILs和金属阳离子螯合型ILs催化CO_(2)化学转化的研究进展,分析比较了不同类型金属配位(螯合)型ILs催化CO_(2)与环氧、末端炔烃、炔丙醇等底物的反应性能与机理;最后,阐述了金属配位(螯合)型ILs应用于CO_(2)吸收与化学转化时存在的问题与面临的挑战与机遇. 展开更多
关键词 离子液体 金属配位型离子液体 金属螯合型离子液体 二氧化碳 吸收 转化
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Experiments and analysis of gold disk targets irradiated by smoothing beams of Xingguang Ⅱ facilities with 350 nm wavelength
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作者 JIANG ShaoEn ZHANG BaoHan +5 位作者 LIU ShenYe YANG JiaMin SUN KeXu HUANG TianXuan DING YongKun ZHENG ZhiJian 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS 2007年第6期716-730,共15页
Gold disk targets were irradiated using focusing and beam smoothing methods on Xingguang (XG-Ⅱ) laser facilities with 350 nm wavelength,0.6 ns pulse width and 20-80 Joules energies. Laser absorption,light scattering ... Gold disk targets were irradiated using focusing and beam smoothing methods on Xingguang (XG-Ⅱ) laser facilities with 350 nm wavelength,0.6 ns pulse width and 20-80 Joules energies. Laser absorption,light scattering and X-ray conversion were experimentally investigated. The experimental results showed that laser ab-sorption and scattered light were about 90% and 10%,respectively,under focusing irradiation,but the laser absorption increased 5%-10% and the scattered light about 1% under the condition of beam smoothing. Compared with the case of fo-cusing irradiation,the laser absorption was effectively improved and the scattered light remarkably dropped under uniform irradiation; then due to the decrease in laser intensity,X-ray conversion increased. This is highly advantageous to the in-ertial confinement fusion. However,X-ray conversion mechanism basically did not change and X-ray conversion efficiency under beam smoothing and focusing irra-diation was basically the same. 展开更多
关键词 beam smoothing lens array laser absorption scattered light X-ray conversion
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End-pumped Nd:YAG zigzag slab laser with weak pump absorption 被引量:2
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作者 付星 柳强 +2 位作者 闫兴鹏 崔进宇 巩马理 《Chinese Optics Letters》 SCIE EI CAS CSCD 2009年第6期492-494,共3页
A diode-pumped Nd:YAG oscillator laser with an end-pumped zigzag slab architecture and weak pump absorption is developed. An output power of 253 W with a slope efficiency of 50.2% and an optical-optical conversion ef... A diode-pumped Nd:YAG oscillator laser with an end-pumped zigzag slab architecture and weak pump absorption is developed. An output power of 253 W with a slope efficiency of 50.2% and an optical-optical conversion efficiency of 39.6% is achieved from the resonator, which emits the maximum power of 290 W with 840-W pump power. An optimum laser diode (LD) array coolant temperature is chosen in an attempt to realize the weak but uniform pump absorption. of zigzag slab resonator depends sensitively on the Furthermore, we have confirmed that the performance incident angle of the beam at the slab end face. 展开更多
关键词 absorption conversion efficiency NEODYMIUM Neodymium lasers PUMPS Resonators
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宽带吸收与极化转换可切换的太赫兹超表面
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作者 王丹 李九生 郭风雷 《物理学报》 SCIE EI CAS CSCD 北大核心 2024年第14期275-282,共8页
本文提出一种具有宽带吸收与极化转换可切换的太赫兹超表面,通过调节二氧化钒电导率可实现太赫兹波吸收和极化转换功能灵活切换.当二氧化钒处于金属状态时,该超表面表现为宽带吸收器,在6.32—18.06 THz范围吸收率大于90%,相对带宽为96.... 本文提出一种具有宽带吸收与极化转换可切换的太赫兹超表面,通过调节二氧化钒电导率可实现太赫兹波吸收和极化转换功能灵活切换.当二氧化钒处于金属状态时,该超表面表现为宽带吸收器,在6.32—18.06 THz范围吸收率大于90%,相对带宽为96.3%.当二氧化钒为绝缘状态时,该结构在2.41—3.42 THz,4.78—7.48 THz和9.53—9.73 THz频率范围表现为极化转换器,极化转换率大于90%.该超表面结构可以用于太赫兹波探测、太赫兹通信以及太赫兹传感等领域应用. 展开更多
关键词 太赫兹 超表面 宽带吸收 极化转换
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电磁吸波与极化转换融合型超表面设计
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作者 贺云 刘鹏成 +3 位作者 付琴 张芝铭 匡元海 曹昭旺 《重庆理工大学学报(自然科学)》 CAS 北大核心 2024年第3期294-299,共6页
针对微波信号多频带吸收与雷达通信信号兼容性的应用需求,利用人工电磁超表面极大设计自由度的特点,结合电磁吸收和极化转换2种电磁波调控机理,设计了一种多阵列单元融合型超表面结构。采用HFSS电磁仿真软件对超表面的电磁吸收性能和极... 针对微波信号多频带吸收与雷达通信信号兼容性的应用需求,利用人工电磁超表面极大设计自由度的特点,结合电磁吸收和极化转换2种电磁波调控机理,设计了一种多阵列单元融合型超表面结构。采用HFSS电磁仿真软件对超表面的电磁吸收性能和极化转换性能进行仿真,并分析其综合调控机理及宽带吸波特性,提出一种将“工”字开口环极化转换超表面阵列单元引入电阻加载的交叉偶极子超表面单元中的设计方法。融合偶极子超表面在低频段的电磁吸波特性以及“工”字开口环超表面在高频段的电磁极化转换特性,扩展超表面结构的电磁吸波带宽。研究结果表明:超表面结构的吸波范围可覆盖2.08~8.36 GHz和13.32~18.46 GHz双频带,多调控机理融合型电磁超表面设计方法具有可行性。 展开更多
关键词 超表面 电磁吸收 极化转换 宽频带 反射系数
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热电厂CO_(2)捕集与利用技术进展 被引量:4
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作者 王成满 赵耀 《广州化工》 CAS 2022年第20期29-31,共3页
2020年全球二氧化碳排放量约为320亿吨,大气中CO_(2)含量正在以每年1 ppm的速度上升,CO_(2)的捕集利用技术正受到越来越多的关注。本文全面介绍了CO_(2)捕集和利用技术,重点对燃烧后捕集技术进行了详细综述和客观评价。认为膜吸收CO_(2... 2020年全球二氧化碳排放量约为320亿吨,大气中CO_(2)含量正在以每年1 ppm的速度上升,CO_(2)的捕集利用技术正受到越来越多的关注。本文全面介绍了CO_(2)捕集和利用技术,重点对燃烧后捕集技术进行了详细综述和客观评价。认为膜吸收CO_(2)捕集方法具有装填密度高、气液接触面积大,操作弹性大,运行成本低优势,具有良好的发展前景;CO_(2)的生物转化利用因具有反应条件温和、过程碳排放极小等优点,使其在CO_(2)资源化利用方面表现出优异的应用前景。 展开更多
关键词 CO_(2) 膜吸收 碳捕集 生物转化
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基于石墨烯和二氧化钒可控吸收/极化转换超表面
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作者 裴娅男 张婷 裴森 《山西电子技术》 2024年第2期64-67,共4页
利用石墨烯和二氧化钒提出了一种可控的超表面,通过调控石墨烯和二氧化钒的导电性能实现了双峰吸收、宽带线-线极化转换。结果表明,当石墨烯的费米能级为1 eV且二氧化钒处于绝缘态时,超表面工作在吸收模式,在0.96 THz和2.23 THz处吸收接... 利用石墨烯和二氧化钒提出了一种可控的超表面,通过调控石墨烯和二氧化钒的导电性能实现了双峰吸收、宽带线-线极化转换。结果表明,当石墨烯的费米能级为1 eV且二氧化钒处于绝缘态时,超表面工作在吸收模式,在0.96 THz和2.23 THz处吸收接近100%的能量。当石墨烯的费米能级为0.1 eV且二氧化钒表现为金属态时,在1.56~3.56 THz频率范围内变换为线-线极化转换的功能,极化转换率大于90%。同时,采用电流分布详细阐明了本文所提超表面的工作原理。该超表面有望在偏振控制器、成像、传感等紧凑型太赫兹器件领域具有重要的应用。 展开更多
关键词 超表面 吸收 极化转换 石墨烯 二氧化钒
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0.53μm激光与等离子体相互作用实验研究 被引量:4
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作者 丁永坤 郑志坚 +7 位作者 唐道源 刘慎业 陈正林 梅启庸 祁兰英 李三伟 丁耀南 刘忠礼 《强激光与粒子束》 EI CAS CSCD 1996年第2期215-220,共6页
利用神光-Ⅰ激光装置的南路光束经KDP晶体倍频后的0.53μm激光与金盘靶相互作用,重点研究了吸收、X光转换、SRS、超热电子和离子发射行为。结果表明,采用短波长激光,吸收和X-光转换率明显提高。
关键词 激光 等离子体 X-光转换 非线性过程
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Dual-acceptor engineering of donor-acceptor type molecules for all-round boosting anti-tumor phototherapy
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作者 Hua Gu Wen Sun +2 位作者 Jianjun Du Jiangli Fan Xiaojun Peng 《Smart Molecules》 2024年第2期104-110,共7页
The integration of robust photon-absorption capacity,high reactive oxygen speciesyields and photothermal conversion efficiency(PCE)into a single phototheranosticnano-agents is ideal but rarely reported.This study empl... The integration of robust photon-absorption capacity,high reactive oxygen speciesyields and photothermal conversion efficiency(PCE)into a single phototheranosticnano-agents is ideal but rarely reported.This study employed a dual-acceptorengineering strategy utilizing isoindigo and selenium-substituted[1,2,5]thiadiazolo[3,4-c]pyridine to augment the molar extinction coefficient and spin-orbitcoupling effect,respectively,resulting in a substantial enhancement of photonabsorptionability and non-radiative decay energy-release process of donoracceptortype phototherapy molecules.As the optimal phototherapy agent,IID-PSe exhibited a high molar extinction coefficient two times that of photosensitizer,excellent 1O2 yield(15%)and PCE(34%),exhibiting great potential forphototherapy.After encapsulating with DSPE-PEG2000,IID-PSe NPs showedexcellent anti-tumor phototherapy ability both in vitro and in vivo.This workprovides an effective idea for designing high-performance photosensitive dyeswith high efficiency phototherapy output. 展开更多
关键词 anti-tumor phototherapy dual-acceptor engineering photon-absorption ability photothermal conversion efficiency reactive oxygen yield
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