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| 1 | Mathematical Models for Combined Refraction-Diffraction of Waves on Non-Uniform Current and Depth显示文摘Two mathematical models for combined refraction-diffraction of regular and irregular waves on non-uniform current in water of slowly varying topography are presented in this paper. Model I is derived by wave theory and variational principle separately. It has two kinds of expressions including the dissipation term. Model n is based on the energy conservation equation with energy flux through the wave crest lines in orthogonal curvilinear coordinates and the wave kinematic conservation equation. The analysis and comparison and special cases of these two models are also given. | Hong Guangwen Professor, Research Institute of Coastal and Ocean Engineering, Hohai University, 1 Xikang Road, Nanjing 210024 | 1996 | China Ocean Engineering1996，11，4： | 35 |
| 2 | 基于Flash技术的虚拟实验室设计与实现显示文摘采用Flash技术设计和开发虚拟实验室具有较好的适切性,本文以职业学校电工实验教学为例设计了虚拟实验室系统,通过综合运用实验、演示、讨论等教学策略,达到帮助和促进学生实验学习的目标。 | 武法提 胡亦宏 | 2006 | 教育信息化2006，，9： | 25 |
| 3 | The Noether's Theory of Birkhoffian Systems~*显示文摘By using the generalized quasi-symmetry of the infinitesimal transformation of the transformation group G_r, the Noether’s theory for Birkhoffian systems (including Noether’s theorem and its inverse) has been established. An example is given. | 梅凤翔 | 1993 | Science China Mathematics1993，36，12： | 25 |
| 4 | Trends in particulate matter and its chemical compositions in China from 2013–2017显示文摘Accurate determination of the atmospheric particulate matter mass concentration and chemical composition is helpful in exploring the causes and sources of atmospheric enthalpy pollution and in evaluating the rationality of environmental air quality control strategies.Based on the sampling and chemical composition data of PM2.5 in different key regions of China in the CARE-China observation network,this research analyzes the environmental air quality data released by the China National Environmental Monitoring Centre during the studied period to determine the changes in the particulate matter mass concentration in key regions and the evolution of the corresponding chemical compositions during the implementation of the Action Plan for Prevention and Control of Air Pollution from 2013-2017.The results show the following.(1)The particulate matter mass concentration in China showed a significant downward trend;however,the PM2.5 annual mass concentration in 64%of cities exceeds the New Chinese Ambient Air Quality Standard(CAAQS)GradeⅡ(GB3095-2012).The region to the east of the Taihang Mountains,the Fenhe and Weihe River Plain and the Urumqi-Changji regions in Xinjiang,all have PM2.5 concentration loading that is still high,and heavy haze pollution occurred frequently in the autumn and winter.(2)During the heavy pollution in the autumn and winter,the concentrations of sulfate and organic components decreased significantly.The mean SO42-concentration in PM2.5 decreased by 76%,12%,81%and 38%in Beijing-Tianjin-Hebei(BTH),the Pearl River Delta(PRD),the Sichuan-Chongqing region(SC)and the Fenhe and Weihe River Plain,respectively.The mean organic matter(OM)concentration decreased by 70%,44%,48%and 31%,respectively,and the mean concentration of NH4+decreased by 68%,1.6%,38%and 25%,respectively.The mean elemental carbon(EC)concentration decreased by 84%and 20%in BTH and SC,respectively,and it increased by 61%and 11%in the PRD and Fenhe and Weihe River Plain,respectively.The mean concentration of mineral and unresolved chemical components(MI)dropped by 70%,24%and 13%in BTH,the PRD and the Fenhe and Weihe River Plain,respectively.The change in the PM2.5 chemical composition is consistent with the decrease of the PM2.5mass concentration.(3)In 2015,the mean OM concentration contributions to fine particles and coarse particles were 13-46%and 46-57%,respectively,and the mean MI concentration contributions to fine particles and coarse and particles were 31-60%and 39-73%,respectively;these values are lower than the 2013 values from the key regions,which is the most important factor behind the decrease of the particulate matter mass concentration.From 2013 to 2015,among the chemical components of different particle size fractions,the peak value of the coarse particle size fraction decreased significantly,and the fine particle size fractions of SO42-,NO3-,and NH4+decreased with the decrease of the particulate matter mass concentration in different particle size fractions.The fine-particle size peaks of SO42-,NO3-and NH4+shifted from 0.65-1.1μm to the finer size range of0.43-0.65μm during the same time frame. | Yuesi WANG Wenjie LI Wenkang GAO Zirui LIU Shili TIAN Rongrong SHEN Dongsheng JI Shuai WANG Lili WANG Guiqian TANG Tao SONG Mengtian CHENG Gehui WANG Zhengyu GONG Jiming HAO Yuanhang ZHANG | 2019 | Science China Earth Sciences2019，62，12： | 23 |
| 5 | Efficacy and safety of herbal medicines in treating gastric ulcer:A review显示文摘Gastric ulcer is a common disorder of the digestive system.Current therapeutic regimens largely rely on Western medicine.However,numerous studies have demonstrated that herbal medicines can effectively treat gastric ulcer in humans and various animal models via divergent mechanisms.This review updates the efficacy and safety of herbal medicines in treating gastric ulcer,and the mechanisms of their action in humans and animal models.Studies have demonstrated that the efficacy of herbal medicines is comparable or superior to that of drugs such as omeprazole or cimetidine in humans and animal models,and herbal medicines display fewer adverse effects.The mechanisms by which herbal medicines benefit gastric ulcer include stimulation of mucous cell proliferation,anti-oxidation,and inhibition of gastric acid secretion and H(+)/K(+)-ATPase activity.Some herbal medicines also exhibit antimicrobial properties.Utilization of herbal medicines could be a valuable alternative to treat gastric ulcer in humans effectively,with few adverse effects. | Wei-Ping Bi Hui-Bin Man Mao-Qiang Man | 2014 | World Journal of Gastroenterology2014，20，45： | 21 |
| 6 | 桑枝化学成分黄酮的药理作用及其应用研究进展显示文摘黄酮类化合物是桑枝的主要药理活性化学成分,主要包括了槲皮素、斛皮苷、异斛皮苷、芦丁等,本文以下就主要对桑枝化学成分黄酮的抗菌抗炎、降血糖、降血脂等药理作用及其应用进展进行了阐述,旨在为进一步提高黄酮的利用水平提供帮助。 | 张丹丹 | 2017 | 中医临床研究2017，9，30： | 19 |
| 7 | Rapid improvement of PM2.5 pollution and associated health benefits in China during 2013–2017显示文摘Exposure to fine particulate matter(PM2.5)is known to harm public health.In China,after implementation of aggressive emissions control measures under the Action Plan of Air Pollution Prevention and Control(2013-2017),air quality has significantly improved.In this work,we investigated changes in PM2.5 exposure and the associated health impacts in China for the period 2013-2017.We used an optimal estimator of PM2.5 combining in-situ observations,satellite measurements,and simulations from a chemical transport model to derive the spatial and temporal variations in PM2.5 exposure,and then used welldeveloped exposure-response functions to estimate the premature deaths attributable to PM2.5 exposure.We found that national population-weighed annual mean PM2.5 concentrations decreased from 67.4μgm-3 in 2013 to 45.5μgm-3 in 2017(32%reduction).This rapid decrease in PM2.5 pollution led to a 14%reduction in premature deaths due to long-term exposure.We estimated that,during 2013-2017,the premature deaths attributable to long-term PM2.5 exposure decreased from 1.2 million(95%CI:1.0,1.3;fraction of total mortality:13%)in 2013 to 1.0 million(95%CI:0.9,1.2;10%)in 2017.Despite the rapid decrease in annual mean PM2.5 concentrations,health benefits associated with reduced long-term exposure were limited,because for many cities,the PM2.5 levels remain at the portion where the exposure-response function is less steeper than that at the lowconcentration end.We also found that the deaths associated with acute exposure decreased by 61%during 2013-2017 due to rapid reduction in the number of heavily polluted days.Our results confirm that clean air policies in China have mitigated the air pollution crisis;however,continuous emissions reduction efforts are required to protect citizens from air pollution. | Tao XUE Jun LIU Qiang ZHANG Guannan GENG Yixuan ZHENG Dan TONG Zhu LIU Dabo GUAN Yu BO Tong ZHU Kebin HE Jiming HAO | 2019 | Science China Earth Sciences2019，62，12： | 17 |
| 8 | Artemisinin, the Magic Drug Discovered from Traditional Chinese Medicine显示文摘Artemisinin and its derivatives represent the most important and influential class of drugs in the fight against malaria. Since the discovery of artemisinin in the early 1970s, the global community has made great strides in characterizing and understanding this remarkable phytochemical and its unique chemical and pharmacological properties. Today, even as artemisinin continues to serve as the foundation for antimalarial therapy, numerous challenges have surfaced in the continued application and development of this family of drugs. These challenges include the emergence of delayed treatment responses to artemisinins in malaria and efforts to apply artemisinins for non-malarial indications. Here, we provide an overview of the story of artemisinin in terms of its past, present, and future. In particular, we comment on the current understanding of the mechanism of action (MOA) of artemisinins, and emphasize the importance of relating mechanistic studies to therapeutic outcomes, both in malarial and non-malarial contexts. | Jigang Wang Chengchao Xu Yin Kwan Wong Yujie Li Fulong Liao Tingliang Jiang Youyou Tu | 2019 | Engineering2019，5，1： | 16 |
| 9 | Impact of China’s Air Pollution Prevention and Control Action Plan on PM2.5 chemical composition over eastern China显示文摘China promulgated the Air Pollution Prevention and Control Action Plan(the Action Plan)in 2013 and developed stringent control measures to mitigate fine particulate matter(PM2.5) pollution.Here,we investigated the PM2.5 chemical composition changes over eastern China associated with the Action Plan during 2013-2017 using satellite-based PM2.5 chemical composition data derived using CMAQ simulations and satellite inputs.The PM2.5 concentrations decreased considerably during this time as a result of the reductions in all chemical species in PM2.5.The population-weighted mean concentrations over eastern China decreased from 11.1 to 6.7μgm-3 for SO42-,13.8-13.1μgm-3 for NO3-,7.4-5.8μgm-3 for NH4+,9.9-8.4μgm-3 for OM,4.6-3.8μg m-3 for BC and 12.9-9.6μg m-3 for other species in PM2.5.SO42-had the largest reduction of 40%,while NO3-had the lowest reduction of 5%,resulting in a greater fraction of NO3-and a smaller fraction of SO42-in PM2.5.Among the three key regions,Beijing-Tianjin-Hebei had the largest reduction in PM2.5 and its chemical compositions.The decrease in SO42-concentrations was in line with the reduction of SO2 emissions,and the major driver of the SO2 emission reductions was the industrial sector.The decrease in NO3 concentrations was limited because the decrease in SO2 emissions and the stable NH3 emissions facilitated the formation of NO3-from HNO3,which partially offset the reduction in NOx emissions driven by the power sector.To mitigate PM2.5 pollution more effectively,future efforts are needed to reduce NH3 emissions. | Guannan GENG Qingyang XIAO Yixuan ZHENG Dan TONG Yuxuan ZHANG Xiaoye ZHANG Qiang ZHANG Kebin HE Yang LIU | 2019 | Science China Earth Sciences2019，62，12： | 16 |
| 10 | Temperature action and effect of concrete-filled steel tubular bridges:A review显示文摘Concrete-filled steel tube(CFST)has been widely applied in bridges due to its excellent structural and constructional performance.In CFST bridges,temperature action is not only an important but also a special load that must be considered in bridge design,construction and structural evaluation.This paper presents an overview on current researches of the temperature action and effect of CFST bridges.The historical and spatial characteristics as well as corresponding influencing factors of temperature distributions are summarized,and classifications of temperature actions are also reviewed.Results show that in-depth investigations of the contributions of temperature influencing factors can help to effectively reduce the adverse temperature effects on CFST bridges in the design stage.Due to the lack of long-term measurements and insufficient use of historical meteorological data,research on the representative value along with correlation analysis of CFST temperature actions and meteorological parameters have to be further carried out.In the meanwhile,a decomposition method of temperature distribution is proposed based on structural effects of CFST bridges in this paper.The decomposed temperature actions can be used for more accurate effect calculation than traditional temperature action classification method,especially for CFST truss bridges.At last,specific temperature action patterns still need to be investigated in some of the special problems,such as longitudinal temperature differences along the CFST arch rib and thermal debonding in the CFST interface.Further investigations are required on the accurate simulation of temperature distribution of CFST bridges considering the shading effects of components and terrain. | Jiang Liu Yongjian Liu Chenyu Zhang Qiuhong Zhao Yi Lyu Lei Jiang | 2020 | Journal of Traffic and Transportation Engineering(English Edition)2020，7，2： | 15 |
| 11 | Rock-breaking mechanism and experimental analysis of confined blasting of borehole surrounding rock显示文摘The rock-breaking mechanism and effect of confined blasting were analysed by blasting and impact dynamic mechanics, fluid dynamic mechanics, fracture mechanics as well as blasting experiment. The results showed that the fracturing of surrounding rock in confined blasting condition is the result of coaction of rock pre-cracking by shock wave and stress wave and the continuing expanding crackenhancement of confined medium, and the model of crack development of borehole surrounding rock in confined blasting condition was established. This study acquired the damage range of surrounding rock under the action of shock wave and stress wave, as well as the crack development characteristics of surrounding rock after the wedge-in confined medium into the crack space. Deep-hole confined blasting experiment on large rock showed that the high-efficient utilisation of in-hole explosive was achieved and the safety of rock blasting operation was ensured. Safe static rock-breaking under the action of high-efficient explosive blasting was achieved as well as the unification of super dynamic load of explosive blasting and static rock-breaking of water medium. | Liu Changyou Yang Jingxuan Yu Bin | 2017 | International Journal of Mining Science and Technology2017，27，5： | 12 |
| 12 | 何首乌块根中砷、镉、汞和铅含量的检测及其富集特性显示文摘The contents of As, Cd, Hg and Pb in root tubers of annual and biennial plants of Polygonum multiflorum Thunb. in Jiangsu Province were 0.32, 0.24, 0, 1.25 and 0.20, 0.26, 1.67×10 -4, 1.32 mg·kg -1 respectively, which totally met the standards of GTSIEMPP (WM2—2001). Biology concentration factors (BCF) of Cd is 2.4-2.6, which indicates that the root tuber of P. multiflorum has a strong accumulative action to Cd. While the accumulative action to As, Hg and Pb is not strong, BCF are 0.025-0.015, 0-6.40×10 -4 and 0.06 respectively. | 李正 杭悦宇 周义峰 | 2005 | 植物资源与环境学报2005，14，2： | 9 |
| 13 | Saliency guided local and global descriptors for effective action recognition显示文摘This paper presents a novel framework for human action recognition based on salient object detection and a new combination of local and global descriptors. We first detect salient objects in video frames and only extract features for such objects.We then use a simple strategy to identify and process only those video frames that contain salient objects. Processing salient objects instead of all frames not only makes the algorithm more efficient, but more importantly also suppresses the interference of background pixels. We combine this approach with a new combination of local and global descriptors, namely3D-SIFT and histograms of oriented optical flow(HOOF), respectively. The resulting saliency guided3D-SIFT–HOOF(SGSH) feature is used along with a multi-class support vector machine(SVM) classifier for human action recognition. Experiments conducted on the standard KTH and UCF-Sports action benchmarks show that our new method outperforms the competing state-of-the-art spatiotemporal feature-based human action recognition methods. | Ashwan Abdulmunem Yu-Kun Lai Xianfang Sun | 2016 | Computational Visual Media2016，2，1： | 9 |
| 14 | Self-adjusted elastic action and its CBM pool-forming effect of the high rank coal reservoir显示文摘The coal reservoir is a kind of geologic body with considerable elasticity, and its response to stress is more sensitive than the routine ones. In the pool-forming process of the coalbed methane, (CBM) the action of many external geodynamic factors in the coal reservoir is represented by the ability of CBM’s diffusion and migration in the coal reservoir. Therefore, the occurrence of the natural fissures in the coal reservoir becomes a key that determines whether the CBM pool can be formed or not. Based on the principle, the authors have designed a comprehensive method of physical modeling to study the elasticity of the coal matrix block with different coal ranks in the light of the solid to fluid coupling, have established the model of the volume deformation (self-adjusted elastic effect) of the coal reservoir under the condition of the effective stress-adsorption/desorption, and have obtained a correct understanding of the law of the elastic deformation. Afterwards, a new viewpoint, named as the self-closing elastic effect for forming the CBM pool in the high rank reservoir, is put forward, providing an initial point and a scientific basis for a further investigation into its dynamic factors, possible mechanism and role in the CBM energy-balancing system. | QIN Yong FU Xuehai WU Caifang FU Guoyou BU Yingying | 2005 | Chinese Science Bulletin2005，50，S1： | 9 |
| 15 | Policies, Actions and Effects for China's Forestry Response to Global Climate Change显示文摘Climate change is a great concern of various countries, the public and science community, and forest plays an important role in mitigating climate change. The paper made a comprehensive analysis regarding the policy selections of China to promote forestry response to the global climate change, and elaborated the concrete actions and achievements in this regard. Policy selections include: 1) Reinforce tree planting and afforestation, increase the forested area and enhance the capacity of carbon sequestration; 2) Improve forest management and the quality of existing stands, and improve the carbon sequestration services provided by forest ecosystem; 3) Strengthen the soil protection on wetland and forestland, and exert the potentials of carbon sequestration; 4) Boost the nature protection, and conserve the biodiversity; 5) Vigorously exploit forestry bio-energy, and reduce the GHG emission; 6) Enhance the prevention and control of forest fires, diseases and pests as well as of illegal expropriation of forest land, and effectively control the GHG emission; 7) Appropriately increase the use of timber, further improve the utilization rate of timber, extend the use life-span of timber and strengthen the carbon-storing function of timber products; 8) Actively implement forestry programs for carbon sequestration and widen the financing channels for forestry development and carbon sequestration. Meanwhile, with the concrete actions in forestry response to climate change, e.g. setting up a specialized agency responsible for the response to climate change, establishing Asian-Pacific Network for Sustainable Forest Management and Rehabilitation, launching the national evaluation of preferential development areas for forestry CDM (Clean Development Mechanism) projects, initiating the pilot projects for Afforestation and Reforestation Project under the CDM, and creating and operating China Green Carbon Fund, China has made great achievements in her response to climate change. There witnesses a growing increase in the quantity and quality of forest resources in China, which contributes to improving ecological condition, giving play to forest potential in carbon sequestration, and mitigating global climate change. | LI Zhiyong1 LI Nuyun2 HE Youjun1 WU Shuirong1 1. Research Institute of Forestry Policy and Information, Chinese Academy of Forestry, Beijing 100091, P. R. China 2. Office of Response to Climate Change, Energy Conservation and Emission Reduction, State Forestry Administration, Beijing 100714, P. R. China | 2008 | Chinese Forestry Science and Technology2008，7，4： | 8 |
| 16 | Vertical Migration of Fine-Grained Sediments from Interior to Surface of Seabed Driven by Seepage Flows–‘Sub-Bottom Sediment Pump Action'显示文摘A scientific hypothesis is proposed and preliminarily verified in this paper: under the driving of seepage flows, there might be a vertical migration of fine-grained soil particles from interior to surface of seabed, which is defined as ‘sub-bottom sediment pump action' in this paper. Field experiments were performed twice on the intertidal flat of the Yellow River delta to study this process via both trapping the pumped materials and recording the pore pressures in the substrate. Experimental results are quite interesting as we did observe yellow slurry which is mainly composed of fine-grained soil particles appearing on the seabed surface; seepage gradients were also detected in the intertidal flat, under the action of tides and small wind waves. Preliminary conclusions are that ‘sediment pump' occurs when seepage force exceeds a certain threshold: firstly, it is big enough to disconnect the soil particles from the soil skeleton; secondly, the degree of seabed fluidization or bioturbation is big enough to provide preferred paths for the detached materials to migrate upwards. Then they would be firstly pumped from interior to the surface of seabed and then easily re-suspended into overlying water column. Influential factors of ‘sediment pump' are determined as hydrodynamics(wave energy), degree of consolidation, index of bioturbation(permeability) and content of fine-grained materials(sedimentary age). This new perspective of ‘sediment pump' may provide some implications for the mechanism interpretation of several unclear geological phenomena in the Yellow River delta area. | ZHANG Shaotong JIA Yonggang WEN Mingzheng WANG Zhenhao Zhang Yaqi ZHU Chaoqi Li Bowen LIU Xiaolei | 2017 | Journal of Ocean University of China2017，16，1： | 8 |
| 17 | 基于Flash Action Script的虚拟现实的实现显示文摘Flash是美国的MACROMEDIA公司推出的优秀网页动画设计软件,是一种交互式动画设计工具.本文介绍了Flash软件的优点及其特点,探析了基于Flash Action Script的虚拟现实的实现. | 翟彤 | 2007 | 电脑知识与技术(过刊)2007，，2： | 7 |
| 18 | Probiotics for the treatment of Clostridium difficile associated disease显示文摘The purpose of this review paper is to update the current and potential future role of probiotics for Clostridium difficile-associated disease (CDAD). Included in this review, is an update on the testing of newer probiotics (e.g. , Bacillus coagulans GBI-30, 6086) in animal models of CDAD. There is a focus on the modulation of signal transduction pathways (i.e. , transcription factors like cAMP response element-binding, activator protein 1, and nuclear factor kappa B), as well as the inhibition of certain kinases (e.g. , p38 mitogen activated protein kinases) by probiotics. Inhibition of signal transduction by probiotics, such as Saccharomyces boulardii , result in multiple effects on intestinal fluid secretion, neutrophil influx into the colon, inflammation, and colonocyte apoptosis that may positively impact CDAD. Recent clinical approaches with probiotics, for the prevention of primary and recurrent CDAD, are also summarized in this review paper. Future directions for the treatment of CDAD by probiotics are also mentioned in this review. In particular, the use of multi-strain probiotic formulations such as Ecologic AAD and VSL #3 may represent a rationale pharmacological approach, particularly as adjunctive therapies for CDAD. Understanding the mechanistic basis of CDAD, and how probiotics interfere at ceratin steps in the pathogenic process, may also present the opportunity to design other multi-strain probiotics that could have a future impact on CDAD. | Leo R Fitzpatrick | 2013 | World Journal of Gastrointestinal Pathophysiology2013，4，3： | 7 |
| 19 | Level Set interface treatment and its application in Euler method显示文摘Level Set interface treatment method is introduced into Euler method,which is employed for interface treatment method for multi-materials. Combined with the ghost fluid method,the moving interface is tracked. Fifth-order WENO spatial discretization and third-order TVD Runge-Kutta time discretization methods are used. Shock-wave action on bubble,implosion and velocity field Shock effect bubbles; implosion and velocity field are simulated by means of LS-MMIC3D programmed by C++. Nu-merical results show that the Level Set interface treatment method is effective and feasible for multi-material interface treatment in comparison with the WENO method. | WU KaiTeng1,2,HAO Li3,WANG Cheng4 & ZHANG Li1,2 1 Numerical Simulation Sichuan Higher School Key Laboratory,Neijiang Normal University,Neijiang 641112,China 2 College of Mathematics and Information Science,Neijiang Normal University,Neijiang 641112,China 3 College of Science,Beijing University of Civil Engineering and Architecture,Beijing 100044,China 4 State Key Laboratory of Explosion Science and Technology,Beijing Institute of Technology,Beijing 100081,China | 2010 | Science China(Physics,Mechanics & Astronomy)2010，53，2： | 7 |
| 20 | System security of hybrid AC-HVDC-systems challenges and new approaches for combined security assessment,preventive optimization and curative actions显示文摘The intense application of Voltage Source Converter based HVDC interconnections and grids will result in a hybrid AC-HVDC-system. The operation of such a system becomes complex regarding system security and system operation. This paper describes major challenges and proposes potential solutions, including a combined security assessment, preventive optimization and curative actions. A coordination of both systems enables an efficient application of existing transport capacity. | Florian Sass Tom Sennewald Franz Linke Dirk Westermann | 2018 | Global Energy Interconnection2018，1，5： | 7 |
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