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Epitaxial growth of MOCVD-derived YBCO films by modulation of Cu(tmhd)_2 concentration

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Rare Metals 2014年第1期33卷 70-74页

作者： Jie xiong Fei Zhang Xin Liu Rui-peng Zhao Xiao-Hui Zhao bo-Wan Tao School of Microelectronics and Solid-State Electronics University of Electronic Science and Technology of China State Key Laboratory of Electronic Thin Film and Integrated Devices University of Electronic Science and Technology of China

Metal-organic chemical vapor deposition was applied to fabricate YBa2Cu3OT-a （YBCO） films on singlecrystal LaA103 （001） substrates for its high deposition rate, easy adjustment on film composition, and low requirement on vacuum apparatus. The effects of Cu（tmhd）2 concentra- tion in the precursor on the properties of YBCO films were systematically investigated. X-ray diffraction （XRD） reveals that the mole ratio of Cu/Ba in the precursor from 0.77 to 0.97 is helpful to improve the crystallization and out-of-plane orientation of YBCO films; however, it hardly affects the inplane texture. Scanning electron microscope （SEM） shows the dense, crack-free but rough surface, on which there are Cu-O and Ba-Cu-O outgrowths identified by energy-dispersive spectrometer （EDS）. As the mole ratio of Cu/Ba increasing, the average size of Ba-Cu-O precipitates keeps increasing and the film composition becomes inhomoge- neous at the mole ratio of Cu/Ba of 0.97. The 250 nm thick YBCO film prepared at the mole ratio of Cu/Ba of 0.91 shows the critical current density （Jc） of 4.0 ***-2 （77 K, 0 T）.

关键词： MOCVD YBCO Cu(tmhd)2 concentration Cu/Ba ratio

Patterns and drivers of plant sexual systems in the dry-hot valley region of southwestern China

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Plant Diversity 2024年第2期46卷 158-168页

作者： Rong Ma Qi Xu Yongqian Gao Deli peng Hang sun bo Song State Key Laboratory of Plant Diversity and Specialty Crops/Yunnan Key Laboratory for Integrative Conservation of Plant Species with Extremely Small Populations Kunming Institute of BotanyChinese Academy of SciencesKunming 650201China College of Life Sciences Shaanxi Normal UniversityXi'an 710119China Yunnan Forestry Technological College Kunming 650224China School of Life Science/Key Laboratory of Yunnan for Biomass Energy and Biotechnology of Environment Yunnan Normal UniversityKunming 650500YunnanChina

Sexual systems play important roles in angiosperm evolution and exhibit substantial variations among different floras. Thus, studying their evolution in a whole flora is crucial for understanding the formation and maintenance of plant biodiversity and predicting its responses to environmental change. In this study, we determined the patterns of plant sexual systems and their associations with geographic elements and various life-history traits in dry-hot valley region of southwestern China, an extremely vulnerable ecosystem. Of the 3166 angiosperm species recorded in this area, 74.5% were hermaphroditic,13.5% were monoecious and 12% were dioecious, showing a high incidence of diclinous species. Diclinous species were strongly associated with tropical elements, whereas hermaphroditic species were strongly associated with temperate and cosmopolitan elements. We also found that hermaphroditism was strongly associated with showy floral displays, specialist entomophily, dry fruits and herbaceous *** was strongly associated with inconspicuous, pale-colored flowers, generalist entomophily, fleshy fruits, and woody plants, whereas monoecy was strongly associated with inconspicuous, pale-colored flowers, anemophily, dry fruits, and herbaceous plants. In addition, hermaphroditic species with generalist entomophily tended to flower in the dry season, whereas diclinous species with specialist entomophily tended to flower in the rainy season. However, independent of sexual systems, plants that produce dry fruits tended to flower in the rainy season and set fruits in the dry season, but the opposite pattern was found for fleshy fruit-producing plants. Our results suggest that in the dry-hot valleys, plant sexual systems are associated with geographic elements as well as various life-history traits that are sensitive to environmental change.

关键词： Floral traits Fruit type Growth form Pollination system Reproductive phenology

Tailored amorphous titanium oxide and carbon composites for enhanced pseudocapacitive sodium storage

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Journal of Energy Chemistry 2022年第2期31卷 127-132页

作者： meng Shao Chengcheng sun Tianming Chen Ningxiang Wu Runan Zhang Xu Han Yu Shen peng Wu Wei-Wei xiong Weina Zhang Sheng Li Fengwei Huo Key Laboratory of Flexible Electronics(KLOFE)&Institute of Advanced Materials(IAM) Nanjing Tech University(NanjingTech)Nanjing 211800JiangsuChina

As an effective and competitive supplement to the commercialized lithium ion batteries(LIBs),sodium ion batteries(SIBs)have been receiving increasing attention in recent years due to lower cost,richer content,and broader distribution of sodium[1–7].Sodium has similar electrochemical properties to lithium,and thus the concepts for the preparation of electrode materials for SIBs can be borrowed from LIBs[8,9].

关键词： Unsaturated sites Amorphous Fast ion storage Na^(+)storage mechanism Pseudocapacitance

In situ analysis of magnesium alloy using a standoff and double-pulse laser-induced breakdown spectroscopy system

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Frontiers of physics 2016年第5期11卷 151-160页

作者： Yong Xin Lan-xiang sun Zhi-Jia Vang peng Zeng Zhi-bo Cong Li-Feng Qi Key Laboratory of Networked Control Systems Shenyang Institute of Automation Chinese Academy of Sciences Shenyang 110016 China University of Chinese Academy of Sciences Beijing 100049 China

To monitor the components of molten magnesium alloy during the smelting process in real time and online, we designed a standoff double-pulse laser-induced breakdown spectroscopy （LIBS） analysis system that can perform focusing, collecting and imaging of long-range samples. First, we tested the system on solid standard magnesium alloy samples in the laboratory to establish a basis for the online monitoring of the components of molten magnesium alloy in the future. The experimental results show that the diameters of the focus spots are approximately 1 mm at a range of 3 m, the ablation depth of the double-pulse mode is much deeper than that of the single-pulse mode, the optimum interpulse delay of the double pulse is inconsistent at different ranges, and the spectral intensity decays rapidly as the range increases. In addition, the enhancement effect of the double pulse at 1.89 m is greater than that at 2.97 m, the maximum enhancement is 7.1-fold for the Y（I）550.35-nm line at 1.89 m, and the calibration results at 1.89 m are better than those at 2.97 m. At 1.89 m, the determination coefficients （R2） of the calibration curves are approximately 99% for Y, Pr, and Zr; the relative standard deviations （RSDs） are less than 10% for Y, Pr, and Zr; the root mean square errors （RMSEs） are less than 0.037% for Pr and Zr; the limits of detection （LODs） are less than 1000 ppm for Y, Pr, and Zr; and the LODs of Y, Pr, and Zr at 2.97 m are higher than those at 1.89 m. Additionally, we tested the system on molten magnesium alloy in a magnesium alloy plant. The calibration results of the liquid magnesium alloy are not as favorable as those of the sampling solid magnesium alloys. In particular, the RSDs of the liquid magnesium alloy are approximately 20% for Pr and La. However, with future improvements in the experimental conditions, the developed system is promising for the in situ analysis of molten magnesium alloy.

关键词： laser-induced breakdown spectroscopy standoff double-pulse online magnesium alloy

Laparoscopy-assisted gastrectomy for advanced gastric cancer patients with situs inversus totalis: Two case reports and review of literature

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World Journal of Gastrointestinal Surgery 2023年第9期15卷 2063-2073页

作者： Hong-bo Liu Xiao-peng Cai Zhao Lu Bin xiong Chun-Wei peng Department of Gastrointestinal Surgery Hubei Key Laboratory of Tumor Biological Behaviors&Hubei Cancer Clinical Study CenterWuhan Peritoneal Cancer Clinical Medical CenterZhongnan Hospital of Wuhan UniversityWuhan 430070Hubei ProvinceChina School of Nursing Wuhan UniversityWuhan 430070Hubei ProvinceChina

BACKGROUND Situs inversus totalis(SIT)is a rare condition in which the positions of abdominal and thoracic organs present a“mirror image”of the normal ones in the median sagittal *** minimally invasive surgery has evolved to achieve laparoscopic gastrectomy for gastric cancer(GC)patients with SIT,it is difficult to perform lymphadenectomy(LND)in such a transposed anatomical ***,we report the cases of two patients with SIT who successfully underwent laparoscopy-assisted gastrectomy(LAG)with D2 *** SUMMARY Case 1:A 65-year-old man was admitted for intermittent abdominal pain and distension,occasional belching,and acid reflux for 4 *** was diagnosed with GC(cT3N1-2M0)with *** surgery,he had undergone four cycles of neoadjuvant chemotherapy and ***,the patient was evaluated as having a partial response,and laparoscopy-assisted distal gastrectomy with D2 LND and Billroth II reconstruction were *** operation was performed successfully within 240 min with an estimated blood loss of 50 mL and no severe *** patient was discharged on postoperative day(POD)*** 2:A 55-year-old man was admitted for upper abdominal distension with pain and discomfort after eating for 3 *** was diagnosed with GC(cT3N1M0)with *** had a history of hypertension for more than 10 years;however,his blood pressure was well-controlled via regular *** performed laparoscopy-assisted total gastrectomy with D2 LND and Roux-en-Y *** operation was performed successfully within 168 min with an estimated blood loss of 50 mL and no severe *** patient was discharged on POD *** LAG with D2 LND could be considered an accessible,safe,and curative procedure for advanced GC patients with SIT.

关键词： Situs inversus totalis Laparoscopy-assisted gastrectomy Advanced gastric cancer Surgery modality Lymphadenectomy Case report

Demand-side Management Based on Model Predictive Control in Distribution Network for Smoothing Distributed Photovoltaic Power Fluctuations

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Journal of Modern Power Systems and Clean Energy 2022年第5期10卷 1326-1336页

作者： Jian Xu Haobo Fu Siyang Liao boyu Xie Deping Ke Yuanzhang sun xiong Li Xiaotao peng IEEE School of Electrical Engineering and Automation Wuhan UniversityWuhan 430072China Power Dispatching and Control Center of State Grid Jibei Electric Power Company Limited Bejing 100054China

With the rapid increase of distributed photovoltaic(PV) power integrating into the distribution network(DN), the critical issues such as PV power curtailment and low equipment utilization rate have been caused by PV power fluctuations. DN has less controllable equipment to manage the PV power fluctuation. To smooth the power fluctuations and further improve the utilization of PV, the regulation ability from the demandside needs to be excavated. This study presents a continuous control method of the feeder load power in a DN based on the voltage regulation to respond to the rapid fluctuation of the PV power output. PV power fluctuations will be directly reflected in the point of common coupling(PCC), and the power fluctuation rate of PCCs is an important standard of PV ***, a demand-side management strategy based on model predictive control(MPC) to mitigate the PCC power fluctuation is proposed. In pre-scheduling, the intraday optimization model is established to solve the reference power of PCC. In real-time control, the pre-scheduling results and MPC are used for the rolling optimization to control the feeder load demand. Finally,the data from the field measurements in Guangzhou, China are used to verify the effectiveness of the proposed strategy in smoothing fluctuations of the distributed PV power.

关键词： Demand-side management multi-time-scale optimization power fluctuation smoothing load control model predictive control(MPC)

Load Shedding and Restoration for Intentional Island with Renewable Distributed Generation

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Journal of Modern Power Systems and Clean Energy 2021年第3期9卷 612-624页

作者： Jian Xu boyu Xie Siyang Liao Zhiyong Yuan Deping Ke Yuanzhang sun xiong Li Xiaotao peng the School of Electrical Engineering and Automations Wuhan UniversityWuhan 430072China the China Southern Power Grid Research Institute China Southern Power Grid CompanyGuangzhou 510663China

Due to the high penetration of renewable distributed generation(RDG),many issues have become conspicuous during the intentional island operation such as the power mismatch of load shedding during the transition process and the power imbalance during the restoration *** this paper,a phase measurement unit(PMU)based online load shedding strategy and a conservation voltage reduction(CVR)based multi-period restoration strategy are proposed for the intentional island with *** proposed load shedding strategy,which is driven by the blackout event,consists of the load shedding optimization and correction *** the occurrence of the large-scale blackout,the load shedding optimization is solved periodically to obtain the optimal load shedding plan,which meets the dynamic and steady *** the blackout occurs,the correction table updated in real time based on the PMU data is used to modify the load shedding plan to eliminate the power mismatch caused by the fluctuation of *** the system transits to the intentional island seamlessly,multi-period restoration plans are generated to optimize the restoration performance while maintaining power balance until the main grid is ***,CVR technology is implemented to restore more loads by regulating load *** proposed load shedding optimization and restoration optimization are linearized to mixed-integer quadratic constraint programming(MIQCP)*** effectiveness of the proposed strategies is verified with the modified IEEE 33-node system on the real-time digital simulation(RTDS)platform.

关键词： Intentional island renewable distributed generation(RDG) load shedding restoration phase measurement unit(PMU) conservation voltage reduction(CVR)

Sex modification of the association of the radial augmentation index and incident hypertension in a Chinese community-based population

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Journal of Geriatric Cardiology 2021年第1期18卷 39-46页

作者： Qiao QIN Fang-Fang FAN meng-Yuan LIU bo LIU Jia JIA Long ZHANG Yu-Xi LI Yi-meng JIANG peng-Fei sun Dan-Mei HE Jian-Ping LI Ming CHEN bo ZHENG Yan ZHANG Department of Cardiology Institute of Cardiovascular DiseasePeking University First HospitalBeijingChina

BACKGROUND Arterial stiffness,as assessed by aortic ultrasound and pulse wave velocity,is associated with incident ***,there is still no consensus on whether the augmentation index(AI)affects new onset of *** study investigated the relationship of radial AI(r AI)and incident hypertension in a Chinese community-based population without hypertension at *** A total of 1,615 Chinese non-hypertensive participants from an atherosclerosis cohort in Beijing,China were included in our *** r AI normalized to heart rate of 75 beats/min(r AIp75)was obtained using HEM-9000 ***-onset hypertension was defined as blood pressure≥140/90 mm Hg or self-reported hypertension or taking anti-hypertensive medications at the follow up *** regression models were used to evaluate the impact of r AIp75 on the risk of new-onset *** After a mean 2.35-year follow-up,213(13.19%)participants developed incident *** significant relation between r AIp75 and incident hypertension was observed in the whole population after adjustment for possible confounders(adjusted odds ratio(OR)and 95%confidence interval(CI):1.09[0.95-1.27];P=0.2260).However,r AIp75 was significantly associated with incident hypertension in women,but not in men(adjusted OR and 95%CI:1.29[1.06-1.56],P=0.0113 for women;0.91[0.72-1.15],P=0.4244 for men;P for interaction=0.0133).CONCLUSIONS Sex modified the effect of the r AI on incident hypertension in a Chinese,community-based,non-hypertensive *** of the r AI could be considered in women with a high risk of hypertension for the purpose of primary intervention.

关键词： Sex modification of the association of the radial augmentation index and incident hypertension in a Chinese community-based population

Unexpected elastic isotropy in a black phosphorene/TiC2 van der Waals heterostructure with flexible Li-ion battery anode applications

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Nano Research 2017年第9期10卷 3136-3150页

作者： Qiong peng Kangming Hu Baisheng Sa Jian Zhou bo Wu Xianhua Hou Zhimei sun Multiscale Computational Materials Facility College of Materials Science and Engineering Euzhou University Fuzhou 3S0100 China Key Laboratory of Eco-Materials Advanced Technology (Fuzhou University) Fujian Province University Fuzhou 350 I00 China School of Materials Science and Engineering and Center for Integrated Computational Materials Engineering International Research Institute for Multidisciplinary Science Beihang University Beijing 100191 China Guangdong Engineering Technology Research Center of Efficient Green Energy and Environmental Protection Materials School ofPhysics and Telecommunication Engineering South China Normal University Guangzhou 510006 China

Recently, flexible electrodes with biaxial/omnidirectional stretchability have attracted significant attention. However, most existing pliable electrode materials can be only stretched in one direction. In this work, an unexpected isotropic van der Waals (vdW) heterostructure is proposed, based on the assembly of two-dimensional crystals of anisotropic black phosphorene (BP) and transition metal carbide (TiC2). Using vdW-corrected density functional theory calculations, the BP/TiC2 vdW heterostructure was predicted to have excellent structural and mechanical stability, superior electrical conductivity, omnidirectional flexibility, and a high Li storage capacity. We have unraveled the physical origin of the excellent stability, as well as the Li adsorption preferences of the lithiated heterostructure, based on a three-step analysis of the stability of the Li-adsorption processes. In addition, the BP/TiC2 vdW heterostructure can also be applied as the anode material for flexible Na-ion batteries because of its high Na storage capacity and strong Na binding. However, compared with Na adsorption, the capacity is higher, and the adsorption energy is more negative for Li adsorption. Our findings provide valuable insights into the exploration of a rich variety of vdW heterostructures for next-generation flexible energy storage devices.

关键词： van der Waals heterostructure omnidirectional stretchability Li adsorption flexible anode first-principles calculations