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基于共价有机框架非金属位点的光催化CO_(2)还原
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作者 黄浩铭 林清清 +4 位作者 牛青 宁江淇 李留义 毕进红 于岩 《Chinese Journal of Catalysis》 SCIE CAS CSCD 2024年第5期201-208,共8页
光催化CO_(2)还原制备碳基化学品,是解决能源危机的理想途径之一.以往的研究主要聚焦于金属位点催化,尽管金属催化剂具有显著的应用潜力,但其高昂的成本和金属中心易失活的问题,限制了其广泛应用.因此,模拟植物光合作用,探寻基于非金属... 光催化CO_(2)还原制备碳基化学品,是解决能源危机的理想途径之一.以往的研究主要聚焦于金属位点催化,尽管金属催化剂具有显著的应用潜力,但其高昂的成本和金属中心易失活的问题,限制了其广泛应用.因此,模拟植物光合作用,探寻基于非金属位点的光催化剂,为CO_(2)还原提供了新的解决思路.共价有机框架材料(COFs)作为一种新型有机晶态多孔材料,因其高度有序的结构和π共轭体系,通常表现出半导体特性.在COF中引入氮官能团,能有效增强对CO_(2)的吸附和活化能力,有望在COFs上实现非金属光催化CO_(2)还原.本文利用COF异质结材料研究了非金属位点催化CO_(2)还原过程.采用原位合成方法制备出ZnIn_(2)S_(4)@TAz-COF异质结材料.红外光谱、Raman光谱和X-射线衍射等方法证明了异质结材料的成功合成.扫描电镜和透射电镜观察显示,ZnIn_(2)S_(4)纳米片与COF形成了异质互融界面,这对后续研究电子转移路径和光催化增强机制至关重要.通过紫外-可见光漫反射光谱、紫外光电子能谱和Mott-Schottky表征,分析了复合前后样品在能带结构上发生的变化和单独组分的功函数.由此推断,当两者复合后,在费米能级差的驱动下,TAz-COF表面的电子流向ZnIn_(2)S_(4),在界面处形成内建电场,这与差分电荷计算结果相一致.进一步的原位光照X射线光电子能谱研究证实,ZnIn_(2)S_(4)@TAz-COF异质结两相之间存在电荷转移,在界面处形成由TAz-COF指向ZnIn_(2)S_(4)的内建电场.这驱动了ZnIn_(2)S_(4)导带上的光生电子与TAz-COF价带上的光生空穴定向迁移和复合,而TAz-COF导带上还原能力较强的光生电子和ZnIn_(2)S_(4)价带上氧化能力较强的光生空穴被空间分离并参与光催化反应.在以水为电子供体的光催化还原CO_(2)反应中,该异质结材料表现出较好的还原CO_(2)到CO活性和良好的稳定性,其转化效率可与部分金属催化的CO_(2)还原体系相当.密度泛函理论计算和原位光谱分析结果表明,吖嗪基团是CO_(2)分子的吸附和活化位点,吖嗪中的氮原子与CO_(2)中的碳原子的强相互作用确保了CO_(2)向COOH*中间体的转化,最终通过光生电子和质子的协助在COF表面转化为CO.综上所述,本文制备了ZnIn_(2)S_(4)@TAz-COF异质结光催化材料.在可见光照射下,该材料界面处形成的内建电场有效驱动了光生电子和空穴的定向迁移,使得COF导带上具有较强还原能力的光生电子与ZnIn_(2)S_(4)价带上具有较强氧化能力的光生空穴实现了高效的空间分离.在没有金属助催化剂和空穴牺牲剂的条件下,ZnIn_(2)S_(4)@TAz-COF复合光催化剂表现出较好的光催化CO_(2)还原活性.本工作不仅为深入理解非金属位点催化CO_(2)还原机理提供了新视角,也为设计和构建高效CO_(2)还原光催化材料提供了参考. 展开更多
关键词 共价有机框架 光催化 二氧化碳还原 异质结构 非金属位点
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A Single-Board Integrated Millimeter-Wave Asymmetric Full-Digital Beamforming Array for B5G/6G Applications
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作者 qingqing lin Jun Xu +9 位作者 Kai Chen Long Wang Wei Li Zhiqiang Yu Guangqi Yang Jianyi Zhou Zhe Chen Jixin Chen Xiaowei Zhu Wei Hong 《Engineering》 SCIE EI CAS CSCD 2024年第10期35-50,共16页
In this article,a single-board integrated millimeter-wave(mm-Wave)asymmetric full-digital beamforming(AFDBF)array is developed for beyond-fifth-generation(B5G)and sixth-generation(6G)communications.The proposed integr... In this article,a single-board integrated millimeter-wave(mm-Wave)asymmetric full-digital beamforming(AFDBF)array is developed for beyond-fifth-generation(B5G)and sixth-generation(6G)communications.The proposed integrated array effectively addresses the challenge of arranging a large number of ports in a full-digital array by designing vertical connections in a three-dimensional space and successfully integrating full-digital transmitting(Tx)and receiving(Rx)arrays independently in a single board.Unlike the traditional symmetric array,the proposed asymmetric array is composed of an 8×8 Tx array arranged in a square shape and an 8+8 Rx array arranged in an L shape.The center-to-center distance between two adjacent elements is 0.54k0 for both the Tx and Rx arrays,where k0 is the free-space wavelength at 27 GHz.The proposed AFDBF array possesses a more compact structure and lower system hardware cost and power consumption compared with conventional brick-type full-digital arrays.In addition,the energy efficiency of the proposed AFDBF array outperforms that of a hybrid beamforming array.The measurement results indicate that the operating frequency band of the proposed array is 24.25–29.50 GHz.An eight-element linear array within the Tx array can achieve a scanning angle ranging from-47°to+47°in both the azimuth and the elevation planes,and the measured scanning range of each eight-element Rx array is–45°to+45°.The measured maximum effective isotropic radiated power(EIRP)of the eight-element Tx array is 43.2 dBm at 28.0 GHz(considering the saturation point).Furthermore,the measured error vector magnitude(EVM)is less than 3%when 64-quadrature amplitude modulation(QAM)waveforms are used. 展开更多
关键词 Full-digital beamforming array Asymmetric structure Single-board integrated Beyond fifth-generation and sixthgeneration Millimeter-wave communication Complex modulation Printed circuit board Vertical connection
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“三段式”科普思政——化学科普思政建设的探索与实践 被引量:1
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作者 林青青 宋柳宏 +1 位作者 赵家源 赵军龙 《大学化学》 CAS 2023年第7期250-257,共8页
在《全民科学素质行动规划纲要(2021–2035年)》和“双减”等政策的大力推行下,中小学生的科普教育逐渐被大众所重视。与此同时,党和国家对于青少年的思想政治培养也有了新的要求。在此情形下,将科普工作与思政教育相结合不失为一种好... 在《全民科学素质行动规划纲要(2021–2035年)》和“双减”等政策的大力推行下,中小学生的科普教育逐渐被大众所重视。与此同时,党和国家对于青少年的思想政治培养也有了新的要求。在此情形下,将科普工作与思政教育相结合不失为一种好的教育方式。我们在化学科普与课程思政融合的探索和实践中,总结出“三段式”科普思政建设方案,本文将以科普课程“星火燎原”为例,由浅入深,用“三段式”科普,对课程思政融入青少年科普课程的过程进行分析与讨论。 展开更多
关键词 科普教育 化学科普 课程思政
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卤代烃教学中课程思政的探索与实践 被引量:9
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作者 李楚玉 王泽华 +5 位作者 方志强 周子昕 林青青 王云侠 赵军龙 王兰英 《大学化学》 CAS 2021年第3期202-206,共5页
在有机化学教学中推进"课程思政"建设,对于落实"立德树人"根本任务具有重要意义。本文以卤代烃章节的讲授为例,引入芥子气化学武器、氟利昂制冷剂、氟烷麻醉剂、有机氯杀虫剂和格利雅试剂等事例,探讨在教学中将专... 在有机化学教学中推进"课程思政"建设,对于落实"立德树人"根本任务具有重要意义。本文以卤代烃章节的讲授为例,引入芥子气化学武器、氟利昂制冷剂、氟烷麻醉剂、有机氯杀虫剂和格利雅试剂等事例,探讨在教学中将专业知识、专业科普和专业思政进行深度融合,使学生全面客观地认识卤代烃,明白科学道路永无止境,懂得利用专业知识造福人类。 展开更多
关键词 课程思政 有机化学 卤代烃
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“牛仔”很忙——牛仔裤中的化学 被引量:2
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作者 王欢 林青青 +5 位作者 王萌 王梦琛 杨斌 张伟 张婷 赵军龙 《大学化学》 CAS 2020年第11期127-131,共5页
牛仔裤向来被誉为“永不过时的经典”,因其舒适、耐用的特点而广受大家喜爱。然而大量的工业制造对环境也造成了一定的影响。本文将以化学的视角科普牛仔裤中染色、做旧等相关部分的原理,并认识其所产生的化学污染。
关键词 靛蓝 牛仔裤 做旧工艺 科普
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“现代”古董--浅谈做旧工艺中的化学原理 被引量:2
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作者 王梦琛 林青青 +2 位作者 王萌 张伟 赵军龙 《大学化学》 CAS 2021年第10期50-56,共7页
古玩,先人留给我们的宝贵文化遗存物质。本文揭示了古玩变旧的化学原理,并从化学的角度揭示了古玩做旧的“秘密”,就不法商贩利用做旧工艺故意造假的基本化学原理进行解析。但更为重要的是,利用这些化学原理对文物进行保养、修复和复制... 古玩,先人留给我们的宝贵文化遗存物质。本文揭示了古玩变旧的化学原理,并从化学的角度揭示了古玩做旧的“秘密”,就不法商贩利用做旧工艺故意造假的基本化学原理进行解析。但更为重要的是,利用这些化学原理对文物进行保养、修复和复制才是古董做旧的正确使用方式,旨在让读者了解做旧的化学本质,增强读者对文物的重视和关注。 展开更多
关键词 做旧工艺 古董 科普
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Survey on Early-bearing High-yielding Model Plantation of Camellia oleifera 被引量:1
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作者 Jixia YAO Huilin QIN +3 位作者 Yinwei DENG Fenling SU Zhiming ZHANG qingqing lin 《Agricultural Science & Technology》 CAS 2017年第1期93-97,共5页
[Objective] This study was conducted to screen the best variety and optimum planting density for constructing early-bearing high-yielding model plantation of Camellia oleifera. [Methed] This survey was carried out in ... [Objective] This study was conducted to screen the best variety and optimum planting density for constructing early-bearing high-yielding model plantation of Camellia oleifera. [Methed] This survey was carried out in two demonstration bases, one for investigating the relationship between different cultivated varieties with growth and production, the other for investigating the relationship between different planting densities with growth and production. [Result] For different cultivated varieties, Cenruan 2 showed tree height, ground diameter and crown product significantly higher than other two varieties, besides, the per unit area fruit yield of Cenruan 2 was also significantly higher than other two varieties. From flower bud differentiation,the best variety was Changlin 4, which showed number of differentiated flower buds significantly higher than Changlin 27, but there were no significant differences between Cenruan 2 with Changlin 4 and Changlin 27. For different planting densities, plant height and crown product at planting density of 1.5 m×2 m were significantly higher than those of other two planting densities, but from ground diam- eter, the best planting density was 1.5 m×1.0 m, with a ground diameter significantly higher than other two planting densities. From per unit area fruit yield, the best planting density was 1.5 m×2.0 m, under which early plant growth and fruit production were better. Therefore, the best planting density is 2.0 m ×3.0 m when constructing early-bearing high-yielding model plantations. For variety Cenruan 3, it's fruit production is high in the early pedod, and the best planting density is 1.5 m× 2.0 m or 1.0 m×1.5 m when constructing early-bearing high-yielding model plantations, and after 4-6 years when it put into production, the plants could be transplanted. 展开更多
关键词 Camellia oleifera VARIETY Density Early-bearing HIGH-YIELDING
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Characteristics of implicit schemas in patients with major depressive disorder
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作者 Jiayu Yao qingqing lin +4 位作者 Ziwei Zheng Shuangyi Chen Yuan Wang Wenhui Jiang Jianyin Qiu 《General Psychiatry》 CAS CSCD 2022年第3期183-191,共9页
Background Many psychotherapy theories emphasise the importance of self-schema and other-schema,but most previous studies focused on the explicit self-schema in major depressive disorder(MDD).However,the limited studi... Background Many psychotherapy theories emphasise the importance of self-schema and other-schema,but most previous studies focused on the explicit self-schema in major depressive disorder(MDD).However,the limited studies of implicit self-schema in MDD have shown inconsistencies in their findings.Furthermore,only a few studies have investigated the implicit other-schema,and the pathway illustrating how implicit schemas influence depression remains unclear.Aims The primary aim of our study was to explore the characteristics of implicit self-schema and otherschema in patients with MDD.We also examine the chain-mediating effect of attachment relationships and interpersonal trust.Methods The present study included 88 patients with MDD and 88 healthy controls(HCs).The Hamilton Depression Rating Scale-17,Experiences in Close Relationships Inventory—Revised Questionnaire,Trust Scale and the Extrinsic Affective Simon Task(EAST)were used to assess depressive symptoms,attachment relationships,interpersonal trust and implicit schemas,respectively.Paired sample t-test was used to compare the reaction time(RT)for positive and negative words within the two groups.Analysis of covariance was used to explore the difference between two groups from the perspective of implicit schemas and interpersonal patterns.The chain mediation model was verified by bootstrap.Results(1)For interpersonal patterns,patients with MDD scored significantly higher on attachment anxiety(F=82.150,p<0.001)and attachment avoidance(F=23.192,p<0.001)and scored significantly lower on the predictability(F=30.297,p<0.001),dependence(F=39.728,p<0.001)and faith(F=60.997,p<0.001)dimensions of interpersonal trust.(2)As for implicit schemas,no significant difference was found between the RT for positive self-words and negative self-words in patients with MDD(t=−1.056,p=0.294).However,the HC responded faster to positive self-words than negative self-words(t=−3.286,p=0.001).The RT for positive other-words and negative other-words were significantly different in both patients with MDD(t=2.943,p=0.004)and HCs(t=−2.482,p=0.015),with opposite directions.The EAST effect of other-schema in patients with MDD was significantly different from that in HCs(F=13.051,p<0.001).(3)For the total sample,the EAST effect of other-schema significantly correlated with attachment avoidance,interpersonal trust and depressive symptoms.Attachment avoidance and interpersonal trust were the chain mediators between the EAST effect of other-schema and depressive symptoms(95%CI:−0.090 to−0.008).However,no significant results were found for the EAST effect of other-schema when correlation and mediation analyses were performed for HCs and patients with MDD separately.Conclusions This study verified that patients with MDD have abnormal interpersonal patterns and negative implicit schemas.However,no mediating effect of attachment relationships and interpersonal trust was found. 展开更多
关键词 PATIENTS SCHEMA IMPLICIT
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Application of Solar Photovoltaic Water Pumping System in Hainan Agriculture
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作者 Xiangchun YU qingqing lin +1 位作者 Xuedong ZHOU Zhibin YANG 《Asian Agricultural Research》 2013年第12期104-106,110,共4页
With radical socio-economic development and strengthening of regulation of agricultural industrial structure in Hainan Province,fresh water resource becomes increasingly insufficient.Existing water-saving facilities a... With radical socio-economic development and strengthening of regulation of agricultural industrial structure in Hainan Province,fresh water resource becomes increasingly insufficient.Existing water-saving facilities and measures are unable to promote sustainable and stable development of local economy.This needs modern irrigation method.Solar photovoltaic water pumping system is necessary and feasible in Hainan agriculture,and will have directive significance for Hainan Province developing photovoltaic agriculture. 展开更多
关键词 HAINAN AGRICULTURE SOLAR ENERGY PHOTOVOLTAIC pumpi
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Long-term variations of X-ray pulse profiles for the Crab pulsar:data analysis and modeling 被引量:2
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作者 LunHua Shang YuanJie Du +13 位作者 XiangQun Cui ShiJun Dang JiGuang Lu JunTao Bai QiJun Zhi YouLi Tuo linLi Yan LiangWei Huang XinYuan Zhang XiaoMin Bei qingqing lin GuoJun Qiao Hua Shen RiHong Zhu 《Science China(Physics,Mechanics & Astronomy)》 SCIE EI CAS CSCD 2020年第10期111-131,共21页
The pulse profiles of the Crab pulsar(as well as some other pulsars)vary with time.They can lead to a major source of intrinsic timing noise,which lacks a detailed physical model.The phase separation?between the first... The pulse profiles of the Crab pulsar(as well as some other pulsars)vary with time.They can lead to a major source of intrinsic timing noise,which lacks a detailed physical model.The phase separation?between the first left peak(P1)and the second right peak(P2)is a key parameter that shows the variations of pulse profiles for the Crab pulsar.It was found that the evolution of?has a tendency with increasing rates of 0.82?±0.25?,0.80?±0.54?,and 0.77?±0.28?per century for the 2-6,6-15,and15-60 ke V bands,respectively.Furthermore,the flux ratios(P2/P1)of X-ray pulse profiles in the three bands were calculated,and the derived flux ratios were consistent with the radio and X-ray measurements of the Insight-HXMT.In addition to discovering the physical origin of the pulse changes,the high-SNR X-ray pulse profiles were simulated in the annular gap model,and two model parameters(e.g.,the maximum emission heights of the two peaks)were observed to slightly affect the variations of peak separation.We fitted the long-term variations of emission heights of the two peaks and discovered that the emission heights showed increasing tendencies with time.Variations of these emission heights induced a characteristic period derivative,and a complete formula for both the magnetic dipole radiation and wind-particle-induced variations of the moment of inertia was used for the pulsar’s spin-down to obtain the variation rate˙αof the magnetic inclination angle,which was-1.60?per century.Intrinsic timing noise is observed to be mainly induced by the variations of pulse profiles,which might correlate with a characteristic spin period derivative arising from the fluctuations of the emission regions.This work will lay a foundation for understanding the origin of intrinsic timing noise and making high-precision timing models in the future. 展开更多
关键词 radiation mechanisms PULSARS X-RAY
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Somatic Mutations Confer Severe Peripheral Neuropathy in POEMS Syndrome-Associated Multicentric Castleman Disease 被引量:3
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作者 qingqing lin Juying Wei +2 位作者 Jiejing Qian Liangshun You Wenbin Qian 《Neuroscience Bulletin》 SCIE CAS CSCD 2020年第6期664-666,共3页
Dear Editor,POEMS-associated multicentric Castleman disease(POEMS-MCD)is a subtype of MCD that presents POEMS symptoms(polyneuropathy,organomegaly,endocrinopathy,M protein,and skin changes)as well as the manifestation... Dear Editor,POEMS-associated multicentric Castleman disease(POEMS-MCD)is a subtype of MCD that presents POEMS symptoms(polyneuropathy,organomegaly,endocrinopathy,M protein,and skin changes)as well as the manifestations of MCD.Among these symptoms,polyneuropathy is a critical feature.However,its mechanism remains poorly understood.The present study presents a case of severe peripheral neuropathy in a POEMSMCD patient.Whole-exome sequencing(WES),threedimensional modeling,and protein stability analysis demonstrated that the mutation V49G in PDLIM5 resulted in instability of the protein,which may play a key role in the pathogenesis of peripheral neuropathy in POEMSMCD. 展开更多
关键词 POEMS NEUROPATHY CASTLEMAN
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