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Advances in Research on Soil Moisture by Microwave Remote Sensing in China 被引量:9
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作者 SONG Dongsheng ZHAO Kai GUAN Zhi 《Chinese Geographical Science》 SCIE CSCD 2007年第2期186-191,共6页
Soil moisture is an important factor in global hydrologic circulation and plays a significant role in the research of hydrology, climatology, and agriculture. Microwave remote sensing is less limited by climate and ti... Soil moisture is an important factor in global hydrologic circulation and plays a significant role in the research of hydrology, climatology, and agriculture. Microwave remote sensing is less limited by climate and time, and can measure in large scale. With these characteristics, this technique becomes an effective tool to measure soil moisture. Since the 1980s, Chinese researchers have investigated the soil moisture using microwave instruments. The active re- mote sensors are characteristic of high spatial resolution, thus with launch of a series of satellites, active microwave remote sensing of soil moisture will be emphasized. The passive microwave remote sensing of soil moisture has a long research history, and its retrieval algorithms were developed well, so it is an important tool to retrieve large scale moisture information from satellite data in the future. 展开更多
关键词 microwave remote sensing soil moisture active microwave remote sensing passive microwave remote sensing
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Remotely Activated Nanoparticles for Anticancer Therapy 被引量:3
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作者 Luisa Racca Valentina Cauda 《Nano-Micro Letters》 SCIE EI CAS CSCD 2021年第1期174-207,共34页
Cancer has nowadays become one of the leading causes of death worldwide.Conventional anticancer approaches are associated with different limitations.Therefore,innovative methodologies are being investigated,and severa... Cancer has nowadays become one of the leading causes of death worldwide.Conventional anticancer approaches are associated with different limitations.Therefore,innovative methodologies are being investigated,and several researchers propose the use of remotely activated nanoparticles to trigger cancer cell death.The idea is to conjugate two different components,i.e.,an external physical input and nanoparticles.Both are given in a harmless dose that once combined together act synergistically to therapeutically treat the cell or tissue of interest,thus also limiting the negative outcomes for the surrounding tissues.Tuning both the properties of the nanomaterial and the involved triggering stimulus,it is possible furthermore to achieve not only a therapeutic effect,but also a powerful platform for imaging at the same time,obtaining a nano-theranostic application.In the present review,we highlight the role of nanoparticles as therapeutic or theranostic tools,thus excluding the cases where a molecular drug is activated.We thus present many examples where the highly cytotoxic power only derives from the active interaction between different physical inputs and nanoparticles.We perform a special focus on mechanical waves responding nanoparticles,in which remotely activated nanoparticles directly become therapeutic agents without the need of the administration of chemotherapeutics or sonosensitizing drugs. 展开更多
关键词 Anticancer therapy remotely activated nanomedicine Stimuli-responsive nanoparticles Physical stimulation RADIOFREQUENCY Nanoparticle-assisted ultrasound HYPERTHERMIA
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A Comparison of Cloud Layers from Ground and Satellite Active Remote Sensing at the Southern Great Plains ARM Site 被引量:2
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作者 Jinqiang ZHANG Xiang'ao XIA Hongbin CHEN 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2017年第3期347-359,共13页
Using the data collected over the Southern Great Plains ARM site from 2006 to 2010, the surface Active Remote Sensing of Cloud (ARSCL) and CloudSat-CALIPSO satellite (CC) retrievals of total cloud and six specifie... Using the data collected over the Southern Great Plains ARM site from 2006 to 2010, the surface Active Remote Sensing of Cloud (ARSCL) and CloudSat-CALIPSO satellite (CC) retrievals of total cloud and six specified cloud types [low, midlow (ML), high-mid-low (HML), mid, high-mid (HM) and high] were compared in terms of cloud fraction (CF), cloud-base height (CBH), cloud-top height (CTH) and cloud thickness (CT), on different temporal scales, to identify their respective advantages and limitations. Good agreement between the two methods was exhibited in the total CF. However, large discrepancies were found between the cloud distributions of the two methods at a high (240-m) vertical grid spacing. Compared to the satellites, ARSCL retrievals detected more boundary layer clouds, while they underestimated high clouds. In terms of the six specific cloud types, more low- and mid-level clouds but less HML- and high-level clouds were detected by ARSCL than by CC. In contrast, the ARSCL retrievals of ML- and HM-level clouds agreed more closely with the estimations from the CC product. Lower CBHs tended to be reported by the surface data for low-, ML- and HML-level clouds; however, higher CTHs were often recorded by the satellite product for HML-, HM- and high-level clouds. The mean CTs for low- and ML-level cloud were similar between the two products; however, the mean CTs for HML-, mid-, HM- and high-level clouds from ARSCL were smaller than those from CC. 展开更多
关键词 surface SATELLITE active remote sensing CLOUD
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THE ANALYSIS OF REMOTE SENSING IMAGES FOR ACTIVE FAULTS AND EARTHQUAKES IN CHINA
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作者 Zhang Shiliang (Institute of Geology, State Seismological Bureau) 《遥感信息》 CSCD 1990年第A02期7-8,共2页
The Landsat image information has recently been widely applied to structural geology, especially to the analysis of lineaments, owing to their macroscopic, visual and comprehensive features. The images will be more ef... The Landsat image information has recently been widely applied to structural geology, especially to the analysis of lineaments, owing to their macroscopic, visual and comprehensive features. The images will be more effective when applied to the interpretation of active faults. Active faults are widely ditributed in China. Much attention has been paid to the study of active faults both in China and abroad. There is certain controversy concerning the implication of the term "active fault". Strictly speaking, the term should refer only to the faults that are still active in the present day. However, the term also usually refers to the faults which have been active continually or intermittently from the Quaternary (or the end of Tertiary) to the present day. We propose that the tones and the configurations of features on Landsat images are the principal keys to the interpretation of active faults. The faults, which display the most prominent 展开更多
关键词 NNE THE ANALYSIS OF remote SENSING IMAGES FOR ACTIVE FAULTS AND EARTHQUAKES IN CHINA
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Beyond 1,4-addition of in-situ generated(aza-)quinone methides and indole imine methides
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作者 Yan-Li Li Zhi-Ming Li +1 位作者 Kai-Kai Wang Xiao-Long He 《Chinese Chemical Letters》 SCIE CAS CSCD 2024年第7期35-53,共19页
The conjugate addition of in-situ generated(aza-)quinone methides(QMs)and indole imine methides(IIMs)emerged as a powerful protocol to access densely functionalized benzenes and indoles.Hydroxybenzyl alcohols,aminoben... The conjugate addition of in-situ generated(aza-)quinone methides(QMs)and indole imine methides(IIMs)emerged as a powerful protocol to access densely functionalized benzenes and indoles.Hydroxybenzyl alcohols,aminobenzhydryl alcohols,and varied indolylmethanols served as most effective precursors for the in-situ generation of such reactive species under acid conditions.The relevant propargylic alcohol has proven to be an elegant precursor to generate the propargylic-QMs and-IIMs via the acid promoted dehydration process,thus enabling diverse challenging remote activation to proceed conjugate1,6-and 1,8-additions.Moreover,the heteroarene has proven to be workable to transfer the LUMO of the p-QMs and 2-IIMs,thus inducing the remote nucleophilic dearomative additions.The conjugate additions of(aza-)p-QMs and varied IIMs has made significant contribution in the field of remote activation chemistry in past decade.This review summarizes the latest advances of the remote conjugate additions of the in-situ generated QMs and IIMs. 展开更多
关键词 Conjugate addition QMS IIMS LUMO remote activation Dearomative addition
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Integrating vegetation phenological characteristics and polarization features with object-oriented techniques for grassland type identification 被引量:1
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作者 Bin Sun Pengyao Qin +5 位作者 Changlong Li Zhihai Gao Alan Grainger Xiaosong Li Yan Wang Wei Yue 《Geo-Spatial Information Science》 CSCD 2024年第3期794-810,共17页
Due to the small size,variety,and high degree of mixing of herbaceous vegetation,remote sensing-based identification of grassland types primarily focuses on extracting major grassland categories,lacking detailed depic... Due to the small size,variety,and high degree of mixing of herbaceous vegetation,remote sensing-based identification of grassland types primarily focuses on extracting major grassland categories,lacking detailed depiction.This limitation significantly hampers the development of effective evaluation and fine supervision for the rational utilization of grassland resources.To address this issue,this study concentrates on the representative grassland of Zhenglan Banner in Inner Mongolia as the study area.It integrates the strengths of Sentinel-1 and Sentinel-2 active-passive synergistic observations and introduces innovative object-oriented techniques for grassland type classification,thereby enhancing the accuracy and refinement of grassland classification.The results demonstrate the following:(1)To meet the supervision requirements of grassland resources,we propose a grassland type classification system based on remote sensing and the vegetation-habitat classification method,specifically applicable to natural grasslands in northern China.(2)By utilizing the high-spatial-resolution Normalized Difference Vegetation Index(NDVI)synthesized through the Spatial and Temporal Non-Local Filter-based Fusion Model(STNLFFM),we are able to capture the NDVI time profiles of grassland types,accurately extract vegetation phenological information within the year,and further enhance the temporal resolution.(3)The integration of multi-seasonal spectral,polarization,and phenological characteristics significantly improves the classification accuracy of grassland types.The overall accuracy reaches 82.61%,with a kappa coefficient of 0.79.Compared to using only multi-seasonal spectral features,the accuracy and kappa coefficient have improved by 15.94%and 0.19,respectively.Notably,the accuracy improvement of the gently sloping steppe is the highest,exceeding 38%.(4)Sandy grassland is the most widespread in the study area,and the growth season of grassland vegetation mainly occurs from May to September.The sandy meadow exhibits a longer growing season compared with typical grassland and meadow,and the distinct differences in phenological characteristics contribute to the accurate identification of various grassland types. 展开更多
关键词 Grassland types vegetation phenological characteristics polarization feature integrated active and passive remote sensing object-oriented classification
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Magnetogenetics: remote non-invasive magnetic activation of neuronal activity with a magnetoreceptor 被引量:22
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作者 Xiaoyang Long Jing Ye +1 位作者 Di Zhao Sheng-Jia Zhang 《Science Bulletin》 SCIE EI CAS CSCD 2015年第24期2107-2119,共13页
Current neuromodulation techniques such as optogenetics and deep-brain stimulation are transforming basic and translational neuroscience. These two neuro- modulation approaches are, however, invasive since surgical im... Current neuromodulation techniques such as optogenetics and deep-brain stimulation are transforming basic and translational neuroscience. These two neuro- modulation approaches are, however, invasive since surgical implantation of an optical fiber or wire electrode is required. Here, we have invented a non-invasive magnetogenetics that combines the genetic targeting of a mag- netoreceptor with remote magnetic stimulation. The noninvasive activation of neurons was achieved by neuronal expression of an exogenous magnetoreceptor, an iron-sulfur cluster assembly protein 1 (Iscal). In HEK-293 cells and cultured hippocampal neurons expressing this magnetoreceptor, application of an external magnetic field resulted in membrane depolarization and calcium influx in a reproducible and reversible manner, as indicated by the ultrasensitive fluorescent calcium indicator GCaMP6s.Moreover, the magnetogenetic control of neuronal activity might be dependent on the direction of the magnetic field and exhibits on-response and off-response patterns for the external magnetic field applied. The activation of this magnetoreceptor can depolarize neurons and elicit trains of action potentials, which can be triggered repetitively with a remote magnetic field in whole-cell patch-clamp recording. In transgenic Caenorhabditis elegans expressing this magnetoreceptor in myo-3-specific muscle cells or mec-4- specific neurons, application of the external magnetic field triggered muscle contraction and withdrawal behavior of the worms, indicative of magnet-dependent activation of muscle cells and touch receptor neurons, respectively. The advantages of magnetogenetics over optogenetics are its exclusive non-invasive, deep penetration, long-term continuous dosing, unlimited accessibility, spatial uniformity and relative safety. Like optogenetics that has gone through decade-long improvements, magnetogenetics, with continuous modification and maturation, will reshape the current landscape of neuromodulation toolboxes and will have a broad range of applications to basic and translational neuroscience as well as other biological sciences. We envision a new age of magnetogenetics is coming. 展开更多
关键词 Magnetogenetics - Optogenetics Iron-sulfur cluster assembly protein Magnetoreceptor Non-invasive and remote activation Neuronalactivity and circuit
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Understanding clouds and precipitation over the Mount Qomolangma:how does the aerosol activation effect exist?
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作者 Xiangde Xu Wenyue Cai +10 位作者 Tianliang Zhao Hua Zhang Xueliang Guo Wenqing Liu Tianshu Zhang Runze Zhao Chong Wu Yueqing Li Lei Wang Peng Yan Changjun Yang 《Science Bulletin》 2025年第21期3649-3658,共10页
Can the“Roof of the world”Mount Qomolangma(MQ)serve as a“natural laboratory”for the activation effect of aerosols on the cloud-precipitation process?Here,we carried out the vertical observations of aerosols,clouds... Can the“Roof of the world”Mount Qomolangma(MQ)serve as a“natural laboratory”for the activation effect of aerosols on the cloud-precipitation process?Here,we carried out the vertical observations of aerosols,clouds,and precipitation at the MQ,where the dual-radar active remote sensing technique is integrated with precipitation observation for the first time.It is found from the observational study that during the Indian summer monsoon,aerosols from South Asia have a distinct activation effect on the cloud-precipitation process over the MQ.Under dynamic lifting,the increase in aerosols,which inhibits and delays weak precipitation over the MQ,instead intensifies the development of clouds over the MQ,leading to heavy precipitation on the north slope.The synergy of the MQ thermal-dynamic driving mechanism and the aerosol activation effect can trigger the deep convection in the precipitation process on the north slope of the MQ.Cloud development is more intense with the aerosol activation effect,and the diurnal cycle of convective clouds in the vertical change over the MQ presents a lag response to changing aerosols.From the perspective of climate impact on interannual variations,it can also be found that the frequency of light rain over the MQ present the significantly decreased trend,while the frequency of moderate to heavy precipitation on the north slope has a significantly increased trend,revealing the differentiated changes in the precipitation on the south and north slopes of the MQ under the influence of the aerosol activation effect on the cloud-precipitation process. 展开更多
关键词 Aerosols Cloud-precipitation process activation effect Deep convection Mount Qomolangma Dual-radar active remote sensing
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Visible-light-induced controllable transformations of cumulative aryldienes through an energy transfer process
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作者 Ling Qian Ziqi Yu +2 位作者 Jiaxin Liu Yin Wei Min Shi 《Science China Chemistry》 2025年第3期987-1001,共15页
In this work,we report a visible light-induced energy transfer process related photochemical protocol of cumulative diene containing compounds for the construction of benzocyclohexene skeletons or the corresponding ar... In this work,we report a visible light-induced energy transfer process related photochemical protocol of cumulative diene containing compounds for the construction of benzocyclohexene skeletons or the corresponding aromatized structures through an energy transfer process,1,5-hydrogen atom transfer and a 6πelectrocyclization or demethoxylation in the presence of different photocatalysts such as[Ir(dF(Me)ppy)_(2)(dtbbpy)]PF_(6) or thioxanthone.This newly developed photochemical strategy is characterized by mild conditions,broad substrate applicability,good functional group tolerance and good yields.The mechanistic paradigm was clarified by deuterium labeling,kinetic,photophysical and electrochemical analyses,control experiments and density functional theory(DFT)calculations.The transformation of the obtained product to the drug-like molecules such as Sertraline and the luminescent conjugated aromatic compounds has also been disclosed. 展开更多
关键词 visible-light photocatalysis EnT process 1 5-HAT remote C(sp^(3))-H bond activation
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