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    题名 作者 年代 出处 被引量
1Anthropogenic emission inventories in China:a review显示文摘The development of reliable anthropogenic emission inventories is essential for both understanding the sources of air pollution and designing effective air-pollution-control measures in China. However, it is challenging to quantify emissions in China accurately, given the variety of contributing sources, the complexity of the technology mix and the lack of reliable measurements. Over the last two decades,tremendous efforts have been made to improve the accuracy of emission inventories, and significant improvements have been realized. More reliable statistics and survey-based data have been used to reduce the uncertainties in activity rates and technology distributions. Local emission factors and source profiles covering various sources have been measured and reported. Based on these local databases, improved emission inventory models have been developed for power plants, large industrial plants and the residential,transportation and agricultural sectors. In this paper, we review the progress that has been made in developing inventories of anthropogenic emissions in China. We first highlight the major updates that have been made to emission inventory models and the underlying data by source category. We then summarize the sector-based estimates of emissions of different species contained in current inventories. The progress that has been made in the development of model-ready emissions is also presented. Finally, we suggest future directions for further improving the accuracy of emission inventories in China.Meng Li Huan Liu Guannan Geng Chaopeng Hong Fei Liu Yu Song Dan Tong Bo Zheng Hongyang Cui Hanyang Man Qiang Zhang Kebin He 2017National Science Review2017,4,6:100
2A brief introduction to weakly supervised learning显示文摘Supervised learning techniques construct predictive models by learning from a large number of training examples, where each training example has a label indicating its ground-truth output. Though current techniques have achieved great success; it is noteworthy that in many tasks it is difficult to get strong supervision information like fully ground-truth labels due to the high cost of the data-labeling process. Thus,it is desirable for machine-learning techniques to work with weak supervision. This article reviews some research progress of weakly supervised learning, focusing on three typical types of weak supervision:incomplete supervision, where only a subset of training data is given with labels; inexact supervision, where the training data are given with only coarse-grained labels; and inaccurate supervision, where the given labels are not always ground-truth.zhi-hua zhou 2018National Science Review2018,5,1:81
3On the origin and continuing evolution of SARS-CoV-2显示文摘The SARS-Co V-2 epidemic started in late December 2019 in Wuhan, China, and has since impacted a large portion of China and raised major global concern. Herein, we investigated the extent of molecular divergence between SARS-CoV-2 and other related coronaviruses. Although we found only 4% variability in genomic nucleotides between SARS-CoV-2 and a bat SARS-related coronavirus(SARSr-CoV;Ra TG13), the difference at neutral sites was 17%, suggesting the divergence between the two viruses is much larger than previously estimated. Our results suggest that the development of new variations in functional sites in the receptor-binding domain(RBD) of the spike seen in SARS-Co V-2 and viruses from pangolin SARSr-Co Vs are likely caused by natural selection besides recombination. Population genetic analyses of 103 SARS-CoV-2 genomes indicated that these viruses had two major lineages(designated L and S), that are well defined by two different SNPs that show nearly complete linkage across the viral strains sequenced to date. We found that L lineage was more prevalent than the S lineage within the limited patient samples we examined. The implication of these evolutionary changes on disease etiology remains unclear.These findings strongly underscores the urgent need for further comprehensive studies that combine viral genomic data, with epidemiological studies of coronavirus disease 2019(COVID-19).Xiaolu Tang Changcheng Wu Xiang Li Yuhe Song Xinmin Yao Xinkai Wu Yuange Duan Hong Zhang Yirong Wang Zhaohui Qian Jie Cui Jian Lu 2020National Science Review2020,7,6:67
4Pathogenic T-cells and inflammatory monocytes incite inflammatory storms in severe COVID-19 patients显示文摘Pathogenic human coronavirus infections,such as severe acute respiratory syndrome CoV(SARS-CoV)and Middle East respiratory syndrome CoV(MERS-CoV),cause high morbidity and mortality[1,2].Recently,a severe pneumonia-associated respiratory syndrome caused by a new coronavirus(SARS-CoV-2)was reported in December 2019 in the city of Wuhan,Hubei province,China[3-5],which was also named as pneumonia-associated respiratory syndrome(PARS)[6]and can cause coronavirus disease 2019(COVID-19)to seriously endanger human health.Yonggang Zhou Binqing Fu Xiaohu Zheng Dongsheng Wang Changcheng Zhao Yingjie Qi Rui Sun Zhigang Tian Xiaoling Xu Haiming Wei 2020National Science Review2020,7,6:54
5Contrasting trends of PM2.5 and surface-ozone concentrations in China from 2013 to 2017显示文摘Although much attention has been paid to investigating and controlling air pollution in China,the trends of air-pollutant concentrations on a national scale have remained unclear.Here,we quantitatively investigated the variation of air pollutants in China using long-term comprehensive data sets from 2013 to 2017,during which Chinese government made major efforts to reduce anthropogenic emission in polluted regions.Our results show a significant decreasing trend in the PM2.5 concentration in heavily polluted regions of eastern China,with an annual decrease of〜7%compared with measurements in 2013.The measured decreased concentrations of SO2>NO2 and CO(a proxy for anthropogenic volatile organic compounds)could explain a large fraction of the decreased PM2.5 concentrations in different regions.As a consequence;the heavily polluted days decreased significantly in corresponding regions.Concentrations of organic aerosol;nitrate;sulfate,ammonium and chloride measured in urban Beijing revealed a remarkable reduction from 2013 to 2017;connecting the decreases in aerosol precursors with corresponding chemical components closely.However;surface-ozone concentrations showed increasing trends in most urban stations from 2013 to 2017;which indicates stronger photochemical pollution.The boundary-layer height in capital c让ies of eastern China showed no significant trends over the Beijing-Tianjin-Hebei,Yangtze River Delta and Pearl River Delta regions from 2013 to 2017;which confirmed the reduction in anthropogenic emissions.Our results demonstrated that the Chinese government was successful in the reduction of particulate matter in urban areas from 2013 to 2017,although the ozone concentration has increased significantly;suggesting a more complex mechanism of improving Chinese air quality in the future.Yonghong Wang Wenkang Gao Shuai Wang Tao Song Zhengyu Gong Dongsheng Ji Lili Wang Zirui Liu Guiqian Tang Yanfeng Huo Shili Tian Jiayun Li Mingge Li Yuan Yang Biwu Chu Tuukka Petaja Veli-Matti Kerminen Hong He Jiming Hao Markku Kulmala Yuesi Wang Yuanhang Zhang 2020National Science Review2020,7,8:51
6Cold-chain food contamination as the possible origin of COVID-19 resurgence in Beijing显示文摘COVID-19,caused by SARS-CoV-2[1,2],has been contained in China through stringent non-pharmaceutical interventions.Border control and quarantine have effectively prevented the virus from being spread by infected travellers,but the risk of resurgence caused by other routes of introduction and transmission remains unclear,and current strategies to prevent resurgence could be flawed.Since July,SARS-CoV-2 RNA contaminations in frozen food imported from countries with ongoing epidemics have been reported in nine provinces in China[3,4].However,there is no robust evidence of COVID-19 outbreaks initiated by environmentto-human transmission.Here we add to evidence of such transmission by investigating the recent COVID-19 resurgence in Beijing.Xinghuo Pang Lili Ren Shuangsheng Wu Wentai Ma Jian Yang Lin Di Jie Li Yan Xiao Lu Kang Shichang Du Jing Du Jing Wang Gang Li Shuguang Zhai Lijuan Chen Wenxiong Zhou Shengjie Lai Lei Gao Yang Pan Quanyi Wang Mingkun Li Jianbin Wang Yanyi Huang Jianwei Wang COVID-19 Field Response Group COVID-19 Laboratory Testing Group 2020National Science Review2020,7,12:51
7Challenges of Big Data analysis显示文摘Big Data bring new opportunities to modern society and challenges to data scientists. On the one hand,Big Data hold great promises for discovering subtle population paterns and heterogeneities that are not possible with small-scale data. On the other hand, the massive sample size and high dimensionality of Big Data introduce unique computational and statistical challenges, including scalability and storage botleneck, noise accumulation, spurious correlation, incidental endogeneity and measurement errors.hese challenges are distinguished and require new computational and statistical paradigm. his paper gives overviews on the salient features of Big Data and how these features impact on paradigm change on statistical and computational methods as well as computing architectures. We also provide various new perspectives on the Big Data analysis and computation. In particular, we emphasize on the viability of the sparsest solution in high-conidence set and point out that exogenous assumptions in most statistical methods for Big Data cannot be validated due to incidental endogeneity. hey can lead to wrong statistical inferences and consequently wrong scientiic conclusions.Jianqing Fan Fang Han Han Liu 2014National Science Review2014,1,2:57
8Integrated study of the water–ecosystem–economy in the Heihe River Basin显示文摘The ecological water diversion project in the Heihe River Basin is the irst successful case in China in which the ecological systems in a river basin have been rescued. his project serves as a valuable example for the management of ecosystems in other inland river basins. his paper reviews the integrated studies of the water–ecosystem–economy relationship in the Heihe River Basin and concludes that sustainable development in inland river basins requires the basin to be considered as a whole, with the relationships between the upstream, midstream and downstream areas of the basin coordinated appropriately. Successful development in these basins will be relected in an improved output per cubic meter of water and the implementation of integrated river basin management practices.Guodong Cheng Xin Li Wenzhi Zhao Zhongmin Xu Qi Feng Shengchun Xiao Honglang Xiao 2014National Science Review2014,1,3:55
9Tibetan Plateau climate dynamics: recent research progress and outlook显示文摘This paper reviews progress in the study of Tibetan Plateau(TP) climate dynamics over the past decade.Several theoretical frameworks, including thermal adaptation and the TP sensible heat(SH) driving air-pump, have been developed to identify the mechanisms responsible for the circulation anomaly produced by thermal forcing of the TP. Numerical simulations demonstrate that the thermal efects of large-scale orography, including the Tibetan and Iranian Plateaus(TIP), are crucial for the formation of the East Asian and South Asian summer monsoons(SASM) because the surface SH of the TIP is the major driver of the water vapor transport required for the genesis of the north branch of the SASM. he large-scale orography of the TP afects the Asian climate through thermal forcing in spring and summer, and mechanical forcing in winter. he TP forcing can also inluence the Asian summer monsoon(ASM) onset over the Bay of Bengal(BOB) by enhancing the BOB warm pool at the surface and by modulating the South Asian High(SAH) in the upper troposphere. On intra-seasonal timescales, the TP thermal forcing signiicantly modulates spring rainfall in southern China and generates the biweekly oscillation of the SAH in summer. Despite climate warming, the atmospheric heat source over the TP, particularly the spring SH,exhibits a clear weakening trend from the 1980 s to 2000 s. his weakening of the spring SH contributed to the anomalous ‘dry in the north' and ‘wet in the south' rainfall patern observed over East China. Also discussed are challenges to further understanding the mechanism of TP forcing on the multi-scale variability of the ASM.Guoxiong Wu Anmin Duan Yimin Liu Jiangyu Mao Rongcai Ren Qing Bao Bian He Boqi Liu Wenting Hu 2015National Science Review2015,2,1:51
10Continental versus oceanic subduction zones显示文摘Subduction zones are tectonic expressions of convergent plate margins,where crustal rocks descend into and interact with the overlying mantle wedge.hey are the geodynamic system that produces maic arc volcanics above oceanic subduction zones but high-to ultrahigh-pressure metamorphic rocks in continental subduction zones.While the metamorphic rocks provide petrological records of orogenic processes when descending crustal rocks undergo dehydration and anataxis at forearc to subarc depths beneath the mantle wedge,the arc volcanics provide geochemical records of the mass transfer from the subducting slab to the mantle wedge in this period though the mantle wedge becomes partially melted at a later time.Whereas the mantle wedge overlying the subducting oceanic slab is of asthenospheric origin,that overlying the descending continental slab is of lithospheric origin,being ancient beneath cratons but juvenile beneath marginal arcs.In either case,the mantle wedge base is cooled down during the slab–wedge coupled subduction.Metamorphic dehydration is prominent during subduction of crustal rocks,giving rise to aqueous solutions that are enriched in luid-mobile incompatible elements.Once the subducting slab is decoupled from the mantle wedge,the slab–mantle interface is heated by lateral incursion of the asthenospheric mantle to allow dehydration melting of rocks in the descending slab surface and the metasomatized mantle wedge base,respectively.herefore,the tectonic regime of subduction zones changes in both time and space with respect to their structures,inputs,processes and products.Ophiolites record the tectonic conversion from sealoor spreading to oceanic subduction beneath continental margin,whereas ultrahigh-temperature metamorphic events mark the tectonic conversion from compression to extension in orogens.Yong-Fei Zheng Yi-Xiang Chen 2016National Science Review2016,3,4:57
11Deep forest显示文摘Current deep-learning models are mostly built upon neural networks, i.e. multiple layers of parameterized differentiable non-linear modules that can be trained by backpropagation. In this paper, we explore the possibility of building deep models based on non-differentiable modules such as decision trees. After a discussion about the mystery behind deep neural networks, particularly by contrasting them with shallow neural networks and traditional machine-learning techniques such as decision trees and boosting machines,we conjecture that the success of deep neural networks owes much to three characteristics, i.e.layer-by-layer processing, in-model feature transformation and sufficient model complexity. On one hand,our conjecture may offer inspiration for theoretical understanding of deep learning; on the other hand, to verify the conjecture, we propose an approach that generates deep forest holding these characteristics. This is a decision-tree ensemble approach, with fewer hyper-parameters than deep neural networks, and its model complexity can be automatically determined in a data-dependent way. Experiments show that its performance is quite robust to hyper-parameter settings, such that in most cases, even across different data from different domains, it is able to achieve excellent performance by using the same default setting. This study opens the door to deep learning based on non-differentiable modules without gradient-based adjustment, and exhibits the possibility of constructing deep models without backpropagation.Zhi-Hua Zhou Ji Feng 2019National Science Review2019,6,1:52
12Carbon-based supercapacitors for efficient energy storage显示文摘The advancement of modern electronic devices depends strongly on the highly efficient energy sources possessing high energy density and power density. In this regard, supercapacitors show great promise. Due to the unique hierarchical structure, excellent electrical and mechanical properties, and high specific surface area, carbon nanomaterials(particularly, carbon nanotubes, graphene, mesoporous carbon and their hybrids) have been widely investigated as efficient electrode materials in supercapacitors. This review article summarizes progress in high-performance supercapacitors based on carbon nanomaterials with an emphasis on the design and fabrication of electrode structures and elucidation of charge-storage mechanisms. Recent developments on carbon-based flexible and stretchable supercapacitors for various potential applications,including integrated energy sources, self-powered sensors and wearable electronics, are also discussed.Xuli Chen Rajib Paul Liming Dai 2017National Science Review2017,4,3:46
13The Taiji Program in Space for gravitational wave physics and the nature of gravity显示文摘The discovery of gravitational waves(GWs)by the LIGO collaboration [1] in 2016 has provided a direct test on the prediction made by Albert Einstein a century ago based on his general theory of relativity [2].It has caused a significant influence worldwide on the basic research in science.Wen-Rui Hu Yue-Liang Wu 2017National Science Review2017,4,5:41
14Cryospheric Science: research framework and disciplinary system显示文摘Cryospheric changes and their impacts have received increasing concern, extending the research to include the interactions between earth spheres and the impacts of and social adaptation to cryospheric changes. As a result, Cryospheric Science is rapidly developing. However, the research framework of Cryospheric Science has not completely been set up, and the intension and extension of Cryospheric Science are unclear.Following a literature review, the research framework for Cryospheric Science and the discipline components are analysed in this paper. We consider that Cryospheric Science is an inevitable product of international research on the earth and environmental changes as well as on human sustainable development. It will not only strengthen the linkage between the cryosphere and other earth spheres by deepening traditional research areas, but will also bring more focus on the critical roles of the cryosphere in interactions between earth spheres, and will enhance the relationship between cryospheric change and climate, ecology, hydrology, surface environment and sustainable development. The disciplinary tree of Cryospheric Science is developed following the mainstream of change-impacts adaptation. The disciplines of Cryospheric Science were teased out against characteristics of traditional branches and the developing interdisciplinary branches of cryosphere elements, which will provide reference to Cryospheric Science as it systematically grows to maturity.Dahe Qin Yongjian Ding Cunde Xiao Shichang Kang Jianwen Ren Jianping Yang Shiqiang Zhang 2018National Science Review2018,5,2:42
15An overview of multi-task learning显示文摘As a promising area in machine learning, multi-task learning(MTL) aims to improve the performance of multiple related learning tasks by leveraging useful information among them. In this paper, we give an overview of MTL by first giving a definition of MTL. Then several different settings of MTL are introduced,including multi-task supervised learning, multi-task unsupervised learning, multi-task semi-supervised learning, multi-task active learning, multi-task reinforcement learning, multi-task online learning and multi-task multi-view learning. For each setting, representative MTL models are presented. In order to speed up the learning process, parallel and distributed MTL models are introduced. Many areas, including computer vision, bio info rmatics, health informatics, speech, natural language processing, web applications and ubiquitous computing, use MTL to improve the performance of the applications involved and some representative works are reviewed. Finally, recent theoretical analyses for MTL are presented.yu zhang qiang yang 2018National Science Review2018,5,1:43
16Programmable time-domain digital-coding metasurface for non-linear harmonic manipulation and new wireless communication systems显示文摘Optical non-linear phenomena are typically observed in natural materials interacting with light at high intensities, and they benefit a diverse range of applications from communication to sensing. However,controlling harmonic conversion with high efficiency and flexibility remains a major issue in modern optical and radio-frequency systems. Here, we introduce a dynamic time-domain digital-coding metasurface that enables efficient manipulation of spectral harmonic distribution. By dynamically modulating the local phase of the surface reflectivity, we achieve accurate control of different harmonics in a highly programmable and dynamic fashion, enabling unusual responses, such as velocity illusion. As a relevant application, we propose and realize a novel architecture for wireless communication systems based on the time-domain digital-coding metasurface, which largely simplifies the architecture of modern communication systems, at the same time yielding excellent performance for real-time signal transmission. The presented work, from new concept to new system, opens new pathways in the application of metamaterials to practical technology.Jie Zhao Xi Yang Jun Yan Dai Qiang Cheng Xiang Li Ning Hua Qi Jun Chen Ke Guo Dong Bai Shuo Liu Shi Jin Andrea Alù Tie Jun Cui 2019National Science Review2019,6,2:46
17Enhanced secondary pollution offset reduction of primary emissions during COVID-19 lockdown in China显示文摘To control the spread of the 2019 novel coronavirus(COVID-19),China imposed nationwide restrictions on the movement of its population(lockdown)after the Chinese New Year of 2020,leading to large reductions in economic activities and associated emissions.Despite such large decreases in primary pollution,there were nonetheless several periods of heavy haze pollution in eastern China,raising questions about the well-established relationship between human activities and air quality.Here,using comprehensive measurements and modeling,we show that the haze during the COVID lockdown was driven by enhancements of secondary pollution.In particular,large decreases in NOx emissions from transportation increased ozone and nighttime NO_(3)radical formation,and these increases in atmospheric oxidizing capacity in turn facilitated the formation of secondary particulate matter.Our results,afforded by the tragic natural experiment of the COVID-19 pandemic,indicate that haze mitigation depends upon a coordinated and balanced strategy for controlling multiple pollutants.Xin Huang Aijun Ding Jian Gao Bo Zheng Derong Zhou Ximeng Qi Rong Tang Jiaping Wang Chuanhua Ren Wei Nie Xuguang Chi Zheng Xu Liangduo Chen Yuanyuan Li Fei Che Nini Pang Haikun Wang Dan Tong Wei Qin Wei Cheng Weijing Liu Qingyan Fu Baoxian Liu Fahe Chai Steven JDavis Qiang Zhang Kebin He 2021National Science Review2021,8,2:47
18Breeding high-yield superior quality hybrid super rice by rational design显示文摘The challenge of meeting the increasing demand for worldwide rice production has driven a sustained quest for advances in rice breeding for yield. Two breakthroughs that led to quantum leaps in productivity last century were the introduction of semidwarf varieties and of hybrid rice. Subsequent gains in yield have been incremental. The next major leap in rice breeding is now upon us through the application of rational design to create defined ideotypes. The exploitation of wide-cross compatibility and intersubspecific heterosis,combined with rapid genome sequencing and the molecular identification of genes for major yield and quality traits have now unlocked the potential for rational design.Qian Qian Longbiao Guo Steven M.Smith Jiayang Li 2016National Science Review2016,3,3:48
19Aerosol and boundary-layer interactions and impact on air quality显示文摘Air quality is concerned with pollutants in both the gas phase and solid or liquid phases. The latter are referred to as aerosols, which are multifaceted agents affecting air quality, weather and climate through many mechanisms. Unlike gas pollutants, aerosols interact strongly with meteorological variables with the strongest interactions taking place in the planetary boundary layer(PBL). The PBL hosting the bulk of aerosols in the lower atmosphere is affected by aerosol radiative effects. Both aerosol scattering and absorption reduce the amount of solar radiation reaching the ground and thus reduce the sensible heat fluxes that drive the diurnal evolution of the PBL. Moreover, aerosols can increase atmospheric stability by inducing a temperature inversion as a result of both scattering and absorption of solar radiation, which suppresses dispersion of pollutants and leads to further increases in aerosol concentration in the lower PBL.Such positive feedback is especially strong during severe pollution events. Knowledge of the PBL is thus crucial for understanding the interactions between air pollution and meteorology. A key question is how the diurnal evolution of the PBL interacts with aerosols, especially in vertical directions, and affects air quality.We review the major advances in aerosol measurements, PBL processes and their interactions with each other through complex feedback mechanisms, and highlight the priorities for future studies.Zhanqing Li Jianping Guo Aijun Ding Hong Liao Jianjun Liu Yele Sun Tijian Wang Huiwen Xue Hongsheng Zhang Bin Zhu 2017National Science Review2017,4,6:37
20Linking atmospheric pollution to cryospheric change in the Third Pole region: current progress and future prospects显示文摘The Tibetan Plateau and its surroundings are known as the Third Pole(TP). This region is noted for its high rates of glacier melt and the associated hydrological shifts that affect water supplies in Asia. Atmospheric pollutants contribute to climatic and cryospheric changes through their effects on solar radiation and the albedos of snow and ice surfaces; moreover, the behavior and fates within the cryosphere and environmental impacts of environmental pollutants are topics of increasing concern. In this review, we introduce a coordinated monitoring and research framework and network to link atmospheric pollution and cryospheric changes(APCC) within the TP region. We then provide an up-to-date summary of progress and achievements related to the APCC research framework, including aspects of atmospheric pollution’s composition and concentration, spatial and temporal variations, trans-boundary transport pathways and mechanisms, and effects on the warming of atmosphere and changing in Indian monsoon, as well as melting of glacier and snow cover. We highlight that exogenous air pollutants can enter into the TP’s environments and cause great impacts on regional climatic and environmental changes. At last, we propose future research priorities and map out an extended program at the global scale. The ongoing monitoring activities and research facilitate comprehensive studies of atmosphere–cryosphere interactions, represent one of China’s key research expeditions to the TP and the polar regions and contribute to the global perspective of earth system science.Shichang Kang Qianggong Zhang Yun Qian Zhenming Ji Chaoliu Li Zhiyuan Cong Yulan Zhang Junming Guo Wentao Du Jie Huang Qinglong You Arnico K.Panday Maheswar Rupakheti Deliang Chen Orjan Gustafsson Mark H.Thiemens Dahe Qin 2019National Science Review2019,6,4:35
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