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| 1 | Vegetation cover change and the driving factors over northwest China显示文摘In this paper the spatio-temporal variation of vegetation cover in northwest China during the period of 1982-2006 and its driving factors were analyzed using GIMMS/NDVI data. The annual average NDVI was increased with a rate of 0.0005/a in northwest China and there was an obvious difference between regions. The trend line slopes of NDVI were higher than 0.0005 in the Tianshan Moutains and Altay Mountains of Xinjiang,the Qilian Mountains of Gansu and the eastern part of Qinghai,which indicated the vegetation cover was significantly increased in these areas. The trend line slopes of NDVI were lower than 0.0005 in the southern region of Qinghai,the border regions of Shaanxi and Ningxia,the parts of Gansu and Tarim Basin,Turpan and Tuoli in Xinjiang,which indicated the vegetation cover was declined in these areas. The NDVI of woodland,grassland and cultivated land had an ascending tendency during the study period. The study shows that the vegetation cover change was caused by both natural factors and human activities in northwest China. The natural vegetation change,such as forests was influenced by climate change,while human activities were the main reason to the change of planting vegetation. The changes of vegetation covers for different elevations,slopes and slope aspects were quite different. When the elevation is exceeded to 4,000 m,the NDVI increasing trend was very low;the NDVI at the slope of less than 25° was increased by the ecological construction;the variation of NDVI on sunny slope was stronger than that on shady slope. The temperature rose significantly in recent 25 years in northwest China by an average rate of 0.67oC/10a,and precipitation increased by an average rate of 8.15 mm/10a after 1986. There was positive correlation between vegetation cover and temperature and annual precipitation changes. Rising temperature increased the evaporation and drought of soils,which is not conducive to plant growth,and the irrigation in agricultural areas reduced the correlation between agricultural vegetation NDVI and precipitation. The improvement of agricultural production level and the projects of ecological construction are very important causes for the NDVI increase in northwest China,and the ecological effect of large-scale ecological construction projects has appeared. | ShengPei DAI Bo ZHANG HaiJun WANG YaMin WANG LingXia GUO XingMei WANG Dan LI | 2011 | Journal of Arid Land2011,3,1: | 22 |
| 2 | How often should one update control and estimation:review of networked triggering techniques显示文摘Management of resources is a constant topic in industrial systems. How to use minimum communication resources is of particular interest for control and estimation of networked systems. It raises the question for researchers in the field: how often should one update control and estimation? One of the most intelligent approaches is to trigger updates by events. In the literature, event-triggered control and estimation have been widely studied in the last decade. On one hand, events should be triggered sufficiently frequent to maintain system performance;on the other hand, the possibility of Zeno behavior caused by infinite frequency should be avoided. This review aims at revisiting some existing triggering techniques in a unified formulation, separated from system dynamics and control and estimation strategies. It brings readers better understanding of triggering mechanisms, the underlying technical challenges, and some promising future research topics. | Zhiyong CHEN Qing-Long HAN Yamin YAN Zheng-Guang WU | 2020 | Science China(Information Sciences)2020,63,5: | 10 |
| 3 | GABAergic Abnormalities Associated with Sensorimotor Corticostriatal Community Structural Deficits in ErbB4 Knockout Mice and First-Episode Treatment-Naive Patients with Schizophrenia显示文摘The current study was designed to explore how disruption of specific molecular circuits in the cerebral cortex may cause sensorimotor cortico-striatal community structure deficits in both a mouse model and patients with schizophrenia.We used prepulse inhibition(PPI)and brain structural and diffusion MRI scans in 23 mice with conditional ErbB4 knockout in parvalbumin interneurons and 27 matched controls.Quantitative real-time PCR was used to assess the differential levels of GABA-related transcripts in brain regions.Concurrently,we measured structural and diffusion MRI and the cumulative contribution of risk alleles in the GABA pathway genes in firstepisode treatment-naı¨ve schizophrenic patients(n=117)and in age-and sex-matched healthy controls(n=86).We present the first evidence of gray and white matter impairment of right sensorimotor cortico-striatal networks and reproduced the sensorimotor gating deficit in a mouse model of schizophrenia.Significant correlations between gray matter volumes(GMVs)in the somatosensory cortex and PPI as well as glutamate decarboxylase 1 mRNA expression were found in controls but not in knockout mice.Furthermore,these findings were confirmed in a human sample in which we found significantly decreased gray and white matter in sensorimotor cortico-striatal networks in schizophrenic patients.The psychiatric risk alleles of the GABA pathway also displayed a significant negative correlation with the GMVs of the somatosensory cortex in patients.Our study identified that ErbB4 ablation in parvalbumin interneurons induced GABAergic dysregulation,providing valuable mechanistic insights into the sensorimotor cortico-striatal community structure deficits associated with schizophrenia. | Chengcheng Zhang Peiyan Ni Yikang Liu Yang Tian Jinxue Wei Bo Xiang Liansheng Zhao Xiaojing Li Xiaohong Ma Wei Deng Wanjun Guo Rongjun Ni Yamin Zhang Qiang Wang Hailiang Huang Nanyin Zhang Tao Li | 2020 | Neuroscience Bulletin2020,36,2: | 9 |
| 4 | Ni Flower/MXene-Melamine Foam Derived 3D Magnetic/Conductive Networks for Ultra-Efficient Microwave Absorption and Infrared Stealth显示文摘The development of multifunctional and efficient electromagnetic wave absorbing materials is a challenging research hotspot.Here,the magnetized Ni flower/MXene hybrids are successfully assembled on the surface of melamine foam(MF)through electrostatic self-assembly and dip-coating adsorption process,realizing the integration of microwave absorption,infrared stealth,and flame retardant.Remarkably,the Ni/MXene-MF achieves a minimum reflection loss(RLmin)of−62.7 dB with a corresponding effective absorption bandwidth(EAB)of 6.24 GHz at 2 mm and an EAB of 6.88 GHz at 1.8 mm.Strong electromagnetic wave absorption is attributed to the three-dimensional magnetic/conductive networks,which provided excellent impedance matching,dielectric loss,magnetic loss,interface polarization,and multiple attenuations.In addition,the Ni/MXene-MF endows low density,excellent heat insulation,infrared stealth,and flame-retardant functions.This work provided a new development strategy for the design of multifunctional and efficient electromagnetic wave absorbing materials. | Haoran Cheng Yamin Pan Xin Wang Chuntai Liu Changyu Shen Dirk W.Schubert Zhanhu Guo Xianhu Liu | 2022 | Nano-Micro Letters2022,14,4: | 7 |
| 5 | Simple fabrication of superhydrophobic PLA with honeycomb-like structures for high-efficiency oil-water separation显示文摘Polylactic acid(PLA) is one of the most suitable candidates for environmental pollution treatment because of its biodegradability which will not cause secondary pollution to the environment after application.However,there is still a lack of a green and facile way to prepare PLA oil-water separation materials.In this work,a water-assisted thermally induced phase separation method for the preparation of superhydrophobic PLA oil-water separation material with honeycomb-like structures is reported.The PLA material shows great ability in application and could adsorb 27.3 times oil to its own weight.In addition,it could also be applicated as a filter with excellent efficiency(50.9 m^3 m^(-2) h^(-1)). | Xiaolong Wang Yamin Pan Huan Yuan Meng Su Chunguang Shao Chuntai Liu Zhanhu Guo Changyu Shen Xianhu Liu | 2020 | Chinese Chemical Letters2020,31,2: | 7 |
| 6 | Effect of Ti substitution on hydrogen storage properties of Zr_(1-x)Ti_xCo (x = 0, 0.1, 0.2, 0.3) alloys显示文摘Zr1-xTixCo(x = 0, 0.1, 0.2, 0.3) alloys were prepared by arc-melting method and the effect of Ti substitution on hydrogen storage properties was studied systematically. Hydrogen desorption pressure-composition-temperature(PCT) measurements were carried out using Sievert's type volumetric apparatus for ZrCo(at 473 K, 573 K and 673 K) and Zr1-xTixCo alloys(at 673 K), respectively. Products after dehydrogenation were characterized by X-ray diffraction(XRD). In addition, the kinetics of Zr1-xTixCo hydride was investigated at 473 K and 673 K,respectively, under hydrogen pressure of 5 MPa. Results showed that Ti substitution for Zr did not change the crystal structure of ZrCo phase.With the increase of temperature from 473 K to 673 K, the extent of disproportionation for ZrCo alloy increased. With Ti content increasing at 673 K, the desorption equilibrium pressure of Zr1-xTixCo-H2 systems elevated and the disproportionation reaction of Zr1-xTixCo alloys was inhibited effectively. Ti substitution decreased the kinetics rate and the effective hydrogen storage capacity of Zr1-xTixCo alloys slightly.Generally speaking, it was found that Zr0.8Ti0.2Co alloy had better anti-disproportionation property with less decrease of effective hydrogen storage capacity which was beneficial to tritium application in the International Thermonuclear Experimental Reactor(ITER). | Yamin Zhao Rongfeng Li Ruihe Tang Boyan Li Ronghai Yu Wei Liu Huaqin Kou Jianbo Meng | 2014 | Journal of Energy Chemistry2014,23,1: | 6 |
| 7 | Development and validation of a liquid chromatography-mass spectrometry metabonomic platform in human plasma of liver failure caused by hepatitis B virus显示文摘 | Lijun Zhang Xiaofang Jia Xia Peng Qiang Ou Zhengguo Zhang Chao Qiu Yamin Yao Fang Shen Hua Yang Fang Ma Jiefei Wang Zhenghong Yuan | 2010 | Acta Biochimica et Biophysica Sinica2010,42,10: | 6 |
| 8 | Equivalent model of close-packed film cooling holes in nickel-based single crystal cooled blade based on crystallographic theory显示文摘The mechanical properties of nickel-based single crystal thin-walled plate with close-packed film cooling holes were studied based on the equivalent solid material concept. The effective plastic parameters inversion method based on crystallographic theory were proposed. A simplification method for close-packed film cooling hole plates with square and triangular penetration patterns was presented. A large number of finite element analysis results covering different ligament efficiencies and penetration patterns were provided to verify the feasibility of the plastic equivalent principle and simplification method. The results show that the stress–strain curve and resolved shear stresses of simplification models are in consistence with the plate models with close-packed film cooling holes. The equivalent errors of yield strength are all within the error band and the values of equivalent errors are all less than 10%. In addition, the equivalent errors of the positions where maximum resolved shear stress occurs are all less than 15°, indicating the accuracy of plastic equivalent model and simplification method. | Yamin ZHANG Zhixun WEN Haiqing PEI Zhufeng YUE | 2019 | Chinese Journal of Aeronautics2019,32,4: | 6 |
| 9 | 玫瑰香精/壳聚糖芳香微球的制备及其应用研究显示文摘为了提高香精的载料量和包覆率,文章采用乳化交联法,以玫瑰香精为油相、壳聚糖为载体材料,在戊二醛的固化交联作用下制备芳香微球乳液并应用于真丝织物的芳香整理。应用激光粒度分析仪、扫描电镜、紫外可见分光光度计、傅里叶红外光谱仪、热重分析仪和电子鼻分别研究芳香微球的油水比、粒径分布、表面形貌、包覆率、主要官能团、热稳定性及芳香织物的表面形貌与留香性能。研究结果表明:该芳香微球制备的油水比能够达到5︰1,微球粒径分布集中,平均粒径为175 nm,香精包覆率达到78.8%,热稳定性良好。经轧-烘-焙工艺整理后,芳香微球极易成膜附着在织物表面,存放120 d后芳香织物仍有31.6%的香味留存,具有良好的留香缓释性。 | 叶景鹏 Md Yamin Hossain 张国庆 刘国金 王成龙 周岚 林旭 | 2021 | 丝绸2021,58,9: | 6 |
| 10 | Petroleum System of the Sufyan Depression at the Eastern Margin of a Huge Strike-slip Fault Zone in Central Africa显示文摘The present paper mainly studies the petroleum system of the Sufyan Depression in the Muglad Basin of central Africa and analyzes its control of hydrocarbon accumulation. On the basis of comprehensive analysis of effective source rock, reservoir bed types and source-reservoir-seal assemblages, petroleum system theory has been used to classify the petroleum system of the Sufyan Depression. Vertically, the Sufyan Depression consists of two subsystems. One is an Abu Gabra subsystem as a self generating, accumulating and sealing assemblage. The other subsystem is composed of an Abu Gabra source rock, Bentiu channel sandstone reservoir and Darfur group shale seal, which is a prolific assemblage in this area. Laterally, the Sufyan Depression is divided into eastern and western parts with separate hydrocarbon generation centers more than 10 000 m deep. The potential of the petroleum system is tremendous. Recently, there has been a great breakthrough in exploration. The Sufyan C-1 well drilled in the central structural belt obtained high-yielding oil flow exceeding 100 tons per day and controlled geologic reserves of tens of millions of tons. The total resource potential of the Sufyan Depression is considerable. The central structural belt is most favorable as an exploration and development prospect. | ZHANG Yamin GU Qin | 2009 | Acta Geologica Sinica(English Edition)2009,83,6: | 5 |
| 11 | Improved algorithm of light scattering by a coated sphere显示文摘An efficient numerical algorithm for computing the light scattering by a coated sphere is proposed. The calculation of relevant functions by different recurrence algorithms is discussed. The new algorithm avoids the numerical difficulties, which give rise to significant errors encountered in practice by prior methods. Exemplifying results such as extinction efficiency, scattering efficiency, light scattering intensity as well as calculation speed are provided. The results show that this algorithm is efficient, fast, numerically stable and accurate. | Lei Liu Huarui Wang Bin Yu Yamin Xu Jianqi Shen | 2007 | China Particuology2007,5,3: | 5 |
| 12 | Tree-ring-based reconstruction of temperature variability(1445–2011) for the upper reaches of the Heihe River Basin, Northwest China显示文摘Long-term temperature variability has significant effects on runoff into the upper reaches of inland rivers. This paper developed a tree-ring chronology of Qilian juniper(Sabina przewalskii Kom.) from the upper tree-line of the middle Qilian Mountains within the upper reaches of Heihe River Basin, Northwest China for a long-term reconstruction of temperature at the study site. In this paper, tree-ring chronology was used to examine climate-growth associations considering local climate data obtained from Qilian Meteorological Station. The results showed that temperatures correlated extremely well with standardized growth indices of trees(r=0.564, P<0.001). Tree-ring chronology was highest correlated with annual mean temperature(r=0.641, P<0.0001). Annual mean temperature which spans the period of 1445–2011 was reconstructed and explained 57.8% of the inter-annual to decadal temperature variance at the regional scale for the period 1961–2011. Spatial correlation patterns revealed that reconstructed temperature data and gridded temperature data had a significant correlation on a regional scale, indicating that the reconstruction represents climatic variations for an extended area surrounding the sampling sites. Analysis of the temperature reconstruction indicated that major cold periods occurred during the periods of 1450s–1480s, 1590s–1770s, 1810s–1890s, 1920s–1940s, and 1960s–1970s. Warm intervals occurred during 1490s–1580s, 1780s–1800s, 1900s–1910s, 1950 s, and 1980 s to present. The coldest 100-year and decadal periods occurred from 1490s–1580s and 1780s–1800s, respectively, while the warmest 100 years within the studied time period was the 20 th century. Colder events and intervals coincided with wet or moist conditions in and near the study region. The reconstructed temperature agreed well with other temperature series reconstructed across the surrounding areas, demonstrating that this reconstructed temperature could be used to evaluate regional climate change. Compared to the tree-ring reconstructed temperature from nearby regions and records of glacier fluctuations from the surrounding high mountains, this reconstruction was reliable, and could aid in the evaluation of regional climate variability. Spectral analyses suggested that the reconstructed annual mean temperature variation may be related to large-scale atmospheric–oceanic variability such as the solar activity, Pacific Decadal Oscillation(PDO) and El Ni?o–Southern Oscillation(ENSO). | WANG Yamin FENG Qi KANG Xingcheng | 2016 | Journal of Arid Land2016,8,1: | 4 |
| 13 | Rape Breeding and Its Intellectual Property Protection in China显示文摘Rape is the third largest oil crop in the world and the first one in China.The national average rapeseed yield is only 2077.5 kg/hm^(2),and the rapeseed oil yield is 894 kg/hm^(2).This paper introduced the main types,germplasm resources,breeding bases and breeding progress of Chinese rape,and studied its high-quality varieties,breeding patents and new varieties of agricultural plants.We analyzed the main problems such as serious loss of germplasm resources in Brassica campestris L.and Brassica juncea(L.)Czern.et Coss and weak'agricultural chip'in rape field,and put forward strategies such as strengthening the protection of rape germplasm resources,encouraging the development of'agricultural chip'in rape industry clusters with national advantages and characteristics,and strengthening the protection of agricultural intellectual property rights. | Li GAO Leying WU Yamin PENG Yuanpeng SUN Jin ZENG Zhiguo SUN | 2023 | Agricultural Biotechnology2023,12,3: | 4 |
| 14 | Concept of the solar ring mission:An overview显示文摘The concept of the Solar Ring mission was gradually formed from L5/L4 mission concept, and the proposal of its pre-phase study was funded by the National Natural Science Foundation of China in November 2018 and then by the Strategic Priority Program of Chinese Academy of Sciences in space sciences in May 2019. Solar Ring mission will be the first attempt to routinely monitor and study the Sun and inner heliosphere from a full 360-degree perspective in the ecliptic plane. The current preliminary design of the Solar Ring mission is to deploy six spacecraft, grouped in three pairs, on a sub-AU orbit around the Sun. The two spacecraft in each group are separated by about 30?and every two groups by about 120?. This configuration with necessary science payloads will allow us to establish three unprecedented capabilities:(1) determine the photospheric vector magnetic field with unambiguity,(2) provide 360-degree maps of the Sun and the inner heliosphere routinely, and(3) resolve the solar wind structures at multiple scales and multiple longitudes. With these capabilities, the Solar Ring mission aims to address the origin of solar cycle, the origin of solar eruptions, the origin of solar wind structures and the origin of severe space weather events. The successful accomplishment of the mission will advance our understanding of the star and the space environment that hold our life and enhance our capability of expanding the next new territory of human. | WANG YuMing JI HaiSheng WANG YaMin XIA LiDong SHEN ChengLong GUO JingNan ZHANG QuanHao HUANG ZhengHua LIU Kai LI XiaoLei LIU Rui WANG JingXiu WANG Shui | 2020 | Science China(Technological Sciences)2020,63,9: | 4 |
| 15 | Opportunities search of transfer between interplanetary halo orbits in ephemeris model显示文摘In this paper,a two-level search method for searching transfer opportunities between interplanetary halo orbits,exploiting the invariant manifolds of the restricted three-body problem,is proposed.In the method,the first-level search procedure is performed under the conditions of the initial time of escape manifold trajectory of the Sun-Earth halo orbit and the terminal time of capture manifold of the target planet fixed,by solving the optimal two-impulsive heliocentric trajectory to connect the two manifold trajectories.The contour map,helpful to the understanding of the global characteristics of the transfer opportunities,taking the initial time of escape manifold and the terminal time of capture manifold as variables,the optimal velocity increment of the first-level search as objective function,is used for the second-level search.Finally,taking the Earth-Mars and Earth-Venus halo to halo transfers for example,the transfer opportunities in 2015-2017 are searched.The results show the effectiveness of the proposed method and reveal the property of quasi-period of transfer opportunities between interplanetary halo orbits. | WANG YaMin CUI PingYuan QIAO Dong | 2013 | Science China(Technological Sciences)2013,56,1: | 4 |
| 16 | Chinese expert consensus on conversion therapy for hepatocellular carcinoma(2021 edition)显示文摘Recent advances in systemic and locoregional treatments for patients with unresectable or advanced hepatocellular carcinoma(HCC)have resulted in improved response rates.This has provided an opportunity for selected patients with initially unresectable HCC to achieve adequate tumor downstaging to undergo surgical resection,a‘conversion therapy’strategy.However,conversion therapy is a new approach to the treatment of HCC and its practice and treatment protocols are still being developed.Review the evidence for conversion therapy in HCC and develop consensus statements to guide clinical practice.Evidence review:Many research centers in China have accumulated significant experience implementing HCC conversion therapy.Preliminary findings and data have shown that conversion therapy represents an important strategy to maximize the survival of selected patients with intermediate stage to advanced HCC;however,there are still many urgent clinical and scientific challenges for this therapeutic strategy and its related fields.In order to summarize and learn from past experience and review current challenges,the Chinese Expert Consensus on Conversion Therapy for Hepatocellular Carcinoma(2021 Edition)was developed based on a review of preliminary experience and clinical data from Chinese and non-Chinese studies in this field and combined with recommendations for clinical practice.Sixteen consensus statements on the implementation of conversion therapy for HCC were developed.The statements generated in this review are based on a review of clinical evidence and real clinical experience and will help guide future progress in conversion therapy for patients with HCC. | Hui-Chuan Sun Jian Zhou Zheng Wang Xiufeng Liu Qing Xie Weidong Jia Ming Zhao Xinyu Bi Gong Li Xueli Bai Yuan Ji Li Xu Xiao-Dong Zhu Dousheng Bai Yajin Chen Yongjun Chen Chaoliu Dai Rongping Guo Wenzhi Guo Chunyi Hao Tao Huang Zhiyong Huang Deyu Li Gang Li Tao Li Xiangcheng Li Guangming Li Xiao Liang Jingfeng Liu Fubao Liu Shichun Lu Zheng Lu Weifu Lv Yilei Mao Guoliang Shao Yinghong Shi Tianqiang Song Guang Tan Yunqiang Tang Kaishan Tao Chidan Wan Guangyi Wang Lu Wang Shunxiang Wang Tianfu Wen Baocai Xing Bangde Xiang Sheng Yan Dinghua Yang Guowen Yin Tao Yin Zhenyu Yin Zhengping Yu Bixiang Zhang Jialin Zhang Shuijun Zhang Ti Zhang Yamin Zhang Yubao Zhang Aibin Zhang Haitao Zhao Ledu Zhou Wu Zhang Zhenyu Zhu Shukui Qin Feng Shen Xiujun Cai Gaojun Teng Jianqiang Cai Minshan Chen Qiang Li Lianxin Liu Weilin Wang Tingbo Liang Jiahong Dong Xiaoping Chen Xuehao Wang Shusen Zheng Jia Fan 无 | 2022 | Hepatobiliary Surgery and Nutrition2022,11,2: | 4 |
| 17 | Effect of sub-cloud evaporation on the δ^18O of precipitation in Qilian Mountains and Hexi Corridor, China显示文摘sub-cloud evaporation;;precipitation;;stable isotope;;Qilian | ZongXing Li Qi Feng YaMin Wang JianGuo Li XiaoYan Guo YongGe Li | 2016 | Research in Cold and Arid Regions2016,8,5: | 4 |
| 18 | Zinc oxide nano-enabled microfluidic reactor for water purification and its applicability to volatile organic compounds显示文摘This paper reports fast and efficient chemical decontamination of water within a tree-branched centimeter-scale microfluidic reactor.The microreactor integrates Zinc oxide nanowires(ZnO NWs)in situ grown acting as an efficient photocatalytic nanomaterial layer.Direct growth of ZnO NWs within the microfluidic chamber brings this photocatalytic medium at the very close vicinity of the water flow path,hence minimizing the required interaction time to produce efficient purification performance.We demonstrate a degradation efficiency of 95%in o5 s of residence time in one-pass only.According to our estimates,it becomes attainable using microfluidic reactors to produce decontamination of merely 1 l of water per day,typical of the human daily drinking water needs.To conduct our experiments,we have chosen a laboratory-scale case study as a seed for addressing the health concern of water contamination by volatile organic compounds(VOCs),which remain difficult to remove using alternative decontamination techniques,especially those involving water evaporation.The contaminated water sample contains mixture of five pollutants:Benzene;Toluene;Ethylbenzene;m–p Xylenes;and o-Xylene(BTEX)diluted in water at 10 p.p.m.concentration of each.Degradation was analytically monitored in a selective manner until it falls below 1 p.p.m.for each of the five pollutants,corresponding to the maximum contaminant level(MCL)established by the US Environmental Protection Agency(EPA).We also report on a preliminary study,investigating the nature of the chemical by-products after the photocatalytic VOCs degradation process. | Imadeddine Azzouz Yamina Ghozlane Habba Martine Capochichi-Gnambodoe Frédéric Marty Jérôme Vial Yamin Leprince-Wang Tarik Bourouina | 2018 | Microsystems & Nanoengineering2018,4,1: | 4 |
| 19 | Single copper sites dispersed on hierarchically porous carbon for improving oxygen reduction reaction towards zinc-air battery显示文摘The demand for high-performance non-precious-metal electrocatalysts to replace the noble metal-based catalysts for oxygen reduction reaction(ORR)is intensively increasing.Herein,single-atomic copper sites supported on N-doped three-dimensional hierarchically porous carbon catalyst(Cu_(1)/NC)was prepared by coordination pyrolysis strategy.Remarkably,the Cu_(1)/NC-900 catalyst not only exhibits excellent ORR performance with a half-wave potential of 0.894 V(vs.RHE)in alkaline media,outperforming those of commercial Pt/C(0.851 V)and Cu nanoparticles anchored on N-doped porous carbon(CuNPs/NC-900),but also demonstrates high stability and methanol tolerance.Moreover,the Cu_(1)/NC-900 based Zn-air battery exhibits higher power density,rechargeability and cyclic stability than the one based on Pt/C.Both experimental and theoretical investigations demonstrated that the excellent performance of the as-obtained Cu_(1)/NC-900 could be attributed to the synergistic effect between copper coordinated by three N atoms active sites and the neighbouring carbon defect,resulting in elevated Cu d-band centers of Cu atoms and facilitating intermediate desorption for ORR process.This study may lead towards the development of highly efficient non-noble metal catalysts for applications in electrochemical energy conversion. | Wenjie Wu Yan Liu Dong Liu Wenxing Chen Zhaoyi Song Ximin Wang Yamin Zheng Ning Lu Chunxia Wang Junjie Mao Yadong Li | 2021 | Nano Research2021,14,4: | 4 |
| 20 | Regional gravity field modeling based on rectangular harmonic analysis显示文摘Regional gravity field modeling with high-precision and high-resolution is one of the most important scientific objectives in geodesy,and can provide fundamental information for geophysics,geodynamics,seismology,and mineral exploration.Rectangular harmonic analysis(RHA)is proposed for regional gravity field modeling in this paper.By solving the Laplace’s equation of gravitational potential in local Cartesian coordinate system,the rectangular harmonic expansions of disturbing potential,gravity anomaly,gravity disturbance,geoid undulation and deflection of the vertical are derived,and so are the formula for signal degree variance and error degree variance of the rectangular harmonic coefficients(RHC).We also present the mathematical model and detailed algorithm for the solution of RHC using RHA from gravity observations.In order to reduce the edge effects caused by periodic continuation in RHA,we propose the strategy of extending the size of computation domain.The RHA-based modeling method is validated by conducting numerical experiments based on simulated ground and airborne gravity data that are generated from geopotential model EGM2008 and contaminated by Gauss white noise with standard deviation of 2 mGal.The accuracy of the 2.5′×2.5′geoid undulations computed from ground and airborne gravity data is 1 and 1.4cm,respectively.The standard error of the gravity disturbances that downward continued from the flight height of 4 km to the geoid is only 3.1 mGal.Numerical results confirm that RHA is able to provide a reliable and accurate regional gravity field model,which may be a new option for the representation of the fine structure of regional gravity field. | JIANG Tao LI JianCheng DANG YaMin ZHANG ChuanYin WANG ZhengTao KE BaoGui | 2014 | Science China Earth Sciences2014,57,7: | 4 |