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Carbon assimilation characteristics of plants in oasis-desert ecotone and their response to CO_2 enrichment

Science China Earth Sciences 2004年第z1期47卷 39-49页

作者： SU Peixi CHEN Huaishun AN lizhe liu Xinmin Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Six species of more than 20-year-old desert woody plants in the oasis-desert ecotone were selected for study. The results showed that: (1) in different growing seasons δ13C values of assimilating organ varied between -14‰ and -16‰ for Haloxylon ammodendron (HA),-14‰-15‰ for Calligonum mongolicum (CM) and-25‰- -28‰ for Caragana korshinskii(CK), Nitraria sphaerocarpa (NS) and Hedysarum scoparium (HS). (2) The net photosynthetic rate (Pn) of HA and CM was significantly higher than those of the other species. With the decrease in Pn for the six species, their intercellular CO2 concentration increased, but stomatal limitation value decreased under the intensive light. At the same time, the photochemical efficiency of PS II dropped to different degrees. (3) The CO2 enrichment experiment demonstrated that, Pn of HA and CM increased to different extent under 450 umol/mol, but their Pn reduced or approximated to the current condition under 650 umol/mol. Under 450 umol/mol the efficiency for solar energy utilization of CK and HS significantly reduced and under 650 umol/mol their respiration rate exceeded photosynthesis rate. It can be concluded that HA and CM have some function of pathway for C4, but the other three species have the function for C3. The decline in their Pn is mainly caused by non-stomatal factors. HA, CM, CKand HS exhibited photoinhibition, which disappeared in a short time. This is a kind of positive readjustment to adapting to the desert environment. HA and CM can adapt to the high CO2 environment, but CK and HS cannot. With the rise in atmospheric CO2 concentration and climate warming, the latter two species in the oasis-desert ecotone may be gradually degraded or even disappear.

关键词： oasis-desert ecotone, carbon assimilation, stable carbon isotope ratio, photoinhibition, CO2 enrichment.

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Electric-Field-Treated Ni/Co_(3)O_(4) Film as High-Performance Bifunctional Electrocatalysts for Efficient Overall Water Splitting

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Nano-Micro Letters 2022年第9期14卷 160-173页

作者： Junming Li Jun Li Jun Ren Hong Hong Dongxue liu lizhe liu Dunhui Wang National Laboratory of Solid State Microstructures Collaborative Innovation Center of Advanced MicrostructuresJiangsu Provincial Key Laboratory for NanotechnologySchool of PhysicsNanjing UniversityNanjing 210093People’s Republic of China Hangzhou Dianzi University Hangzhou 310018People’s Republic of China

Rational design of bifunctional electrocatalysts for oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)with excellent activity and stability is of great significance,since overall water splitting is a promising technology for sustainable conversion of clean ***,most electrocatalysts do not simultaneously possess optimal HER/OER activities and their electrical conductivities are intrinsically low,which limit the development of overall water *** this paper,a strategy of electric field treatment is proposed and applied to Ni/Co_(3)O_(4) film to develop a novel bifunctional *** treated by electric field,the conductive channels consisting of oxygen vacancies are formed in the Co_(3)O_(4) film,which remarkably reduces the resistance of the system by almost 2×10^(4) ***,the surface Ni metal electrode is partially oxidized to nickel oxide,which enhances the catalytic *** electric-field-treated Ni/Co_(3)O_(4) material exhibits super outstanding performance of HER,OER,and overall water splitting,and the catalytic activity is significantly superior to the state-of-the-art noble metal catalysts(Pt/C,RuO_(2),and RuO_(2)‖Pt/C couple).This work provides an effective and feasible method for the development of novel and efficient bifunctional electrocatalyst,which is also promising for wide use in the field of catalysis.

关键词： Bifunctional electrocatalyst Overall water splitting Co_(3)O_(4)film Oxygen vacancies Electric field

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Ultrahigh quantum efficiency photodetector and ultrafast reversible surface wettability transition of square In2O3 nanowires

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Nano Research 2017年第8期10卷 2772-2781页

作者： Ming Meng Xinglong Wu Xiaoli Ji Zhixing Gan lizhe liu Jiancang Shen Paul K. Chu School of Physics and Telecommunication Engineering Zhoukou Normal University Zhoukou 466001 China Key Laboratory of Modern Acoustics MOE Institute of Acoustics Collaborative Innovation Center of Advanced Microstructures Notional Laboratory of Solid State Microstructures Nanjing University Nonjing 210093 China School of Electronic Science and Engineering Nanjing University Nanjing 210093 China Key Laboratory of Optoelectronic Technology of Jiangsu Province School of Physical Science and Technology Nanjing Normal University Nanjing 210023 China Department of Physics and Materials Science City University ofHong Kong Tat Chee Avenue Kowloon Hong Kong China

Due to a large surface-to-volume ratio, the optoelectronic performance of low- dimensional semiconductor nanostructure-based photodetectors depends in principle on chemisorption/photodesorption at the exposed surface, but practical examples that show such an effect are still unavailable. Some theoretical calculations have predicted that the {001} facets of In2O3 can effectively accumulate photogenerated holes under irradiation, providing a model material to examine whether the facet cutting of nanowires （NWs） can boost their optoelectronic performance. Herein, we present the design and construction of a novel nanowire-based photodetector using square In2O3 NWs with four exposed {001} crystal facets. The photodetector delivers excellent optoelectronic performance with excellent repeatability, fast response speed, high spectral responsivity （Rλ）, and high external quantum efficiency （EQE）. The Rλ and EQE values are as high as 4.8 × 10^6 A/W and 1.46 × 10^9%, respectively, which are larger than those of other popular semiconductor photodetectors. In addition, the square In2O3 NWs show hydrophobic wettability as manifested by a contact angle of 118° and a fast photoinduced reversible switching behavior is observed.

关键词： square In2O3 nanowires crystal facet photodetector reversible wettability transition

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Asymmetric orbital hybridization in Zn-doped antiperovskite Cu_(1-x)Zn_(x)NMn_(3)enables highly efficient electrocatalytic hydrogen production

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Journal of Energy Chemistry 2024年第2期89卷 304-312,I0008页

作者： Yuxiang Yan Yuxin Cao Zhichao Wang Ka Wang Hengdong Ren Shaoqi Zhang Yi Wang Jian Chen Yong Zhou lizhe liu Jun Dai Xinglong Wu National Laboratory of Solid States Microstructures and School of Physics Nanjing UniversityNanjing 210093JiangsuChina College of Engineering and Applied Sciences Nanjing UniversityNanjing 210093JiangsuChina National Laboratory of Solid States Microstructures and Research Institute of Superconductor Electronics Nanjing UniversityNanjing 210093JiangsuChina School of Mathematics&Physics Jiangsu University Science&TechnologyZhenjiang 212003JiangsuChina

Rational design of efficient and robust earth-abundant alkaline hydrogen evolution reaction(HER)catalysts is a key factor for developing energy conversion ***,antiperovskite nitride CuNMn_(3)has garnered significant interest due to its remarkable properties such as negative/zero thermal expansion and magnetocaloric ***,when utilized as hydrogen evolution catalysts,it encounters large challenge resulting from excessively strong/weak interactions with adsorbed H on Mn/Cu active sites,which leads to low HER *** this study,we introduce an asymmetric orbital hybridization strategy in Zn-doped Cu_(1-x)Zn_(x)NMn_(3)by leveraging the localization of Zn electronic states to reconfigure the electronic structures of Cu and Mn,thereby reducing the energy barrier for water dissociation and optimizing Cu and Mn active sites for hydrogen adsorption and H_(2)*** evaluations reveal that Cu_(0.85)Zn_(0.15)NMn_(3)with x=0.15 demonstrates exceptional electrocatalytic activity in alkaline electrolytes.A low overpotential of 52 mV at 10 mA cm^(-2)and outstanding stability over a 150-h test period are achieved,surpassing commercial Pt/*** research offers a novel strategy for enhancing HER performance by modulating asymmetric hybridization of electron orbitals between multiple metal atoms within a material structure.

关键词： Cu_(1-x)ZnxNMn_(3) Asymmetric orbital hybridization Hydrogen adsorption Hydrogen production

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Carbon assimilation characteristics of plants in oasis-desert ecotone and their response to CO2 enrichment

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Science China Earth Sciences 2004年第S1期 39-49页

作者： SU Peixi, CHEN Huaishun, AN lizhe & liu XinminCold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China

关键词： oasis-desert ecotone carbon assimilation stable carbon isotope ratio photoinhibition CO2 enrichment.

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基于关联规则分析阎洪臣治疗胸痹心痛用药规律

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中医文献杂志 2021年第2期39卷 66-69页

作者：刘利哲河南省洛阳市中医院洛阳471000

整理阎洪臣教授治疗胸痹患者的病历资料,采用中医传承辅助系统中关联规则等数据挖掘方法研究阎洪臣教授治疗胸痹的用药频次及其药物组合规律,分析阎洪臣教授的用药经验。通过对整理的55个患者的154个处方进行分析,确定阎洪臣教授治疗胸... 详细信息

整理阎洪臣教授治疗胸痹患者的病历资料,采用中医传承辅助系统中关联规则等数据挖掘方法研究阎洪臣教授治疗胸痹的用药频次及其药物组合规律,分析阎洪臣教授的用药经验。通过对整理的55个患者的154个处方进行分析,确定阎洪臣教授治疗胸痹心痛的辨证分型、药物频次及其关联规则。阎洪臣教授治疗胸痹心痛在辨证基础上灵活运用化痰活血药,疗效显著。

关键词：胸痹心痛中医传承辅助系统用药规律数据挖掘名医经验

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圆环共形重叠阵发射多波束形成算法研究

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电子测量技术 2021年第11期44卷 125-130页

作者：赵柯刘丽哲梅立荣中国电子科技集团公司第五十四研究所石家庄050081

针对非重叠固定扇区波束形成指向模糊,主瓣增益低以及旁瓣较高等问题,设计了一种应用于圆环共形的重叠阵算法。该算法将圆阵划分为多个120°互相重叠的扇区,扇区数量和重叠区域可调整,同时采用有向阵元和Taylor加权,使得期望方向发射波... 详细信息

针对非重叠固定扇区波束形成指向模糊,主瓣增益低以及旁瓣较高等问题,设计了一种应用于圆环共形的重叠阵算法。该算法将圆阵划分为多个120°互相重叠的扇区,扇区数量和重叠区域可调整,同时采用有向阵元和Taylor加权,使得期望方向发射波束位于所划分扇区中心区域,获得最大增益。结果显示,与固定扇区非重叠圆阵相比,重叠圆阵发射单波束旁瓣抑制由-10.16dB下降至-21.2dB;发射两波束旁瓣抑制由-18.92dB下降至-24.18dB,主瓣增益由10.76dB上升至15.32dB;发射八波束时各波束主瓣指向精准无偏移且副瓣较低。结果表明,相对于传统固定阵波束形成算法,重叠阵算法在主瓣指向、主瓣增益及副瓣抑制等方面表现更加优良。

关键词：圆环共形重叠阵 Taylor加权多波束

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信息收集中无人机节能轨迹设计与资源优化

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哈尔滨工业大学学报 2024年第9期56卷 48-55页

作者：郭少雄宋志群李勇刘丽哲王斌先进通信网全国重点实验室(中国电子科技集团公司第五十四研究所) 石家庄050081

为优化无线传感器网络(wireless sensor networks,WSN)中无人机(unmanned aerial vehicle,UAV)辅助信息收集系统的能量消耗,在综合考虑无人机飞行能耗和传感器节点上行数据传输能耗的基础上,提出了一种考虑链路间干扰的无人机轨迹和传... 详细信息

为优化无线传感器网络(wireless sensor networks,WSN)中无人机(unmanned aerial vehicle,UAV)辅助信息收集系统的能量消耗,在综合考虑无人机飞行能耗和传感器节点上行数据传输能耗的基础上,提出了一种考虑链路间干扰的无人机轨迹和传感器功率分配联合优化算法。首先,基于实际约束构建了系统能耗最小化问题模型;然后,针对多约束优化问题的非凸性特征,采用块坐标下降法(block coordinate descent,BCD)将系统能耗最小化问题分解为固定无人机轨迹下的功率分配和固定功率分配下的无人机轨迹优化两个子问题,根据子问题的数学特征,采用凸近似法将非凸问题转化成可以求解的近似凸优化问题,通过对两个子问题的交替迭代优化,得到原非凸问题的近似次优解;最后,通过仿真实验验证了所提算法的可行性和有效性。结果表明:所提算法最大可使系统能量消耗降低22%,明显优于对比算法;且随着传感器节点数量的增加,所提算法的优势更加明显。研究结果为WSN中的信息收集提供了一种系统能耗优化思路,即在有限提高无人机飞行能耗的基础上,有效降低系统的能量消耗。

关键词：无线通信无线传感器网络无人机信息收集轨迹设计块坐标下降节能

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