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| 1 | Late Cenozoic deformation subsequence in northeastern margin of Tibet --Detrital AFT records from Linxia Basin显示文摘Two events of Tibet uplifting are revealed by detrital apatite fission track (AFT) age data from Linxia Basin. They occurred at about 14 and 5.4-8.0 MaBP respectively. We interpret the first one to be related to the uplifting of the northern Tibet, which might have resulted from convectively removing the thickened lower lithosphere. The second one is a result of Laji Mountain uplifting. Numerous studies of the Tibetan Plateau suggest that the onset time of the deformation in the northeastern margin of Tibetan Plateau and the time of Tibet attaining to its present elevation is about 8 MaBP. They are approximately coincident with the uplift of Lajishan Mountain. It suggests that the northeastern margin of Tibet propagated northeastwardly to its present site in about 8 MaBP for accommodating the sustained convergence between India-Eurasia plate and for keeping its high elevation. The active block pattern dominating the strong earthquake distribution of Chinese continent probably formed at about 8.0-5.4 MaBP. | ZHENG Dewen (郑德文) ZHANG Peizhen (张培震) WAN Jinglin (万景林) LI Chuanyou (李传友) CAO Jixiu (曹继秀) | 2003 | Science China Earth Sciences2003，46，z2： | 25 |
| 2 | Pattern and timing of late Cenozoic rapid exhumation and uplift of the Helan Mountain,China显示文摘The Helan Mountain, an intraplate deformation belt in the North China Craton, is located in the northern portion of the China North-South seismic belt, and at the northwestern margin of the Ordos Block. The Cenozoic deformation history of the Helan Mountain is characterized by extension along the eastern Helan Mountain fault (EHSF), resulting in the exhumation and uplift of the Helan Mountain, relative to the rifting of the adjacent Yinchuan Basin. Here we present new apatite fission track (AFT) data from several transects adjacent to the EHSF in the central and northern Helan Mountain. AFT ages from the northern Helan Mountain (Dawukou and Zhengyiguan transects) range from 10 Ma to 89 Ma, whereas AFT ages from the southern Helan Mountain (Suyukou transect) are greater than 71 Ma. The AFT data analysis reveals initiation of rapid uplift and exhumation of the Helan Mountain at 10–12 Ma. Additionally, a plot of the AFT ages versus their mean track length shows a distinctive 'boomerang' pattern indicating that the Helan Mountain experienced a discrete phase of accelerated exhumation beginning at 10-12 Ma. Spatially, AFT samples systematically increase in age away from the EHSF and are consistent with late Cenozoic exhumation that was slow in the southwestern Helan Mountain and rapid in the northeastern Helan Mountain, as well more rapid adjacent to the EHSF and slower away from the EHSF. Obviously, the spatial distribution of late Cenozoic exhumation indicates that normal faulting of the EHSF is related to southwestward tilting and rapid exhumation of the Helan Mountain beginning at 10–12 Ma. The uplift and exhumation of the Helan Mountain was a response to the intensive extension of the northwestern margin of the Ordos Block in the late Cenozoic; this occurred under a regional extensional stress field oriented NW-SE along the Yinchuan-Jilantai-Hetao and the Weihe-Shanxi graben systems adjacent to the Ordos Block. | LIU JianHui ZHANG PeiZhen ZHENG DeWen WAN JinLin WANG WeiTao DU Peng LEI QiYun | 2010 | Science China Earth Sciences2010，53，3： | 23 |
| 3 | China’s Urban and Rural Old Age Security System: Challenges and Options显示文摘This paper reviews the development of the urban and rural old age security system in China, and discusses the challenges in the process of constructing a sustained old age security system. Although funding gaps and empty individual accounts have imposed a heavy burden on the sustainability of China’s urban pension system, there is a relatively high coverage rate of 35.3 percent for urban workers. However, China’s pension system provides low coverage rate for rural farmers. The more rapidly aging population and lower incomes in rural areas pose challenges to the vulnerable rural household support system. The separation of the old age security system between rural and urban areas also puts great pressure as a result of urbanization on farmers who lose their farmland. Therefore, it is urgent for China to speed up the reform of its old age security system to provide an institutional support for its economic and social transition. | Dewen Wang | 2006 | China & World Economy2006，14，1： | 23 |
| 4 | Chemical mechanical polishing: Theory and experiment显示文摘For several decades,chemical mechanical polishing(CMP)has been the most widely used planarization method in integrated circuits manufacturing.The final polishing results are affected by many factors related to the carrier structure,the polishing pad,the slurry,and the process parameters.As both chemical and mechanical actions affect the effectiveness of CMP,and these actions are themselves affected by many factors,the CMP mechanism is complex and has been a hot research area for many years.This review provides a basic description of the development,challenges,and key technologies associated with CMP.We summarize theoretical CMP models from the perspectives of kinematics,empirical,its mechanism(from the viewpoint of the atomic scale,particle scale,and wafer scale),and its chemical-mechanical synergy.Experimental approaches to the CMP mechanism of material removal and planarization are further discussed from the viewpoint of the particle wear effect,chemical-mechanical synergy,and wafer-pad interfacial interaction. | Dewen ZHAO Xinchun LU | 2013 | Friction2013，1，4： | 18 |
| 5 | Employment Effectiveness of China's Economic Stimulus Package显示文摘用一个输入产量方法,这份报纸在中国的经济和雇用上模仿全球金融危机的影响和出口的衰落。与缩小外部需求,增加国内需求为维持经济生长并且支持雇用变得关键。我们的模仿的结果显示没有显著地减少生长,有雇用的一种投资情形能作为优先级完成雇用最大化的目的。公共投资应该集中于雇用,教育,健康,住房和社会安全到重新平衡中国是经济以便它能认识到支撑并且稳定的经济生长。 | Fang Cai Dewen Wang Huaehu Zhang | 2010 | China & World Economy2010，18，1： | 13 |
| 6 | Apatite fission track thermochronology in the Kuluketage and Aksu areas,NW China:Implication for tectonic evolution of the northern Tarim显示文摘Tarim Precambrian bedrocks are well exposed in the Kuluketage and Aksu areas,where twenty four samples were taken to reveal the denudation history of the northern Tarim Craton.Apatite fission track dating and thermal history modeling suggest that the northern Tarim experienced multi-stage cooling events which were assumed to be associated with the distant effects of the Cimmerian orogeny and India-Eurasia collision in the past.But the first episode of exhumation in the northern Tarim,occurring in the mid-Permian to Triassic,is here suggested to be induced by docking of the Tarim Craton and final amalgamation of the Central Asian Orogenic Belt.The cooling event at ca.170 Ma may be triggered by the Qiangtang-Eurasia collision.Widespread Cretaceous exhumation could be linked with docking of the Lhasa terrane in the late Jurassic.Cenozoic reheating and recooling likely occurred because of the northpropagating stress,however,this has not affected the northern Tarim much because the Tarim is characterized by rigid block-like motion. | Zhiyong Zhang Wenbin Zhu Dewen Zheng Bihai Zheng Wei Yang | 2016 | Geoscience Frontiers2016，7，2： | 8 |
| 7 | Derivation of Plastic Work Rate Done per Unit Volume for Mean Yield Criterion and Its Application显示文摘In Haigh Westergaard stress space linear combination of twin shear stress and Tresca yield functions is called the mean yield (MY) criterion. The mathematical relationship of the criterion and its plastic work rate done per unit volume were derived. A generalized worked example of slab forging was analyzed by the criterion and its corresponding plastic work rate done per unit volume. Then, the precision of the solution was compared with those by Mises and Twin shear stress yield criterions, respectively. It turned out that the calculated results by MY criterion were in good agreement with those by Mises criterion. | Dewen ZHAO Yingjie XIE Xiaowen WANG Xianghua LIU | 2005 | Journal of Materials Science & Technology2005，21，4： | 8 |
| 8 | Distribution of green algae micro-propagules and their function in the formation of the green tides in the coast of Qinhuangdao,the Bohai Sea, China显示文摘Since 2015, a novel green tide has been recurring in the coastal areas of Qinhuangdao at the western coast of the Bohai Sea in China, threatening the environment and ecosystem of the Beidaihe seaside holiday resort along the coast. Micro-propagules of the green algae including gametes, spores, micro-germlings and micro-vegetative fragments play an important role in the formation of green tides. They serve as a 'seed source' of green macroalgae, and their distributions could reflect and influence the 'algae source' of green tides. In this study,monthly surveys in the inshore and offshore areas of the Qinhuangdao coast were conducted from April to September 2016 and in January 2017 to investigate the tempo-spatial distribution patterns and the biomass variations of the green algae micro-propagules. The obtained results show that micro-propagules were mainly distributed in the inshore areas with a significantly decreasing abundance towards offshore areas. Their biomass was highest in July and August, and lowest in winter. The areas that were affected by the green tides showed a remarkably higher abundance of micro-propagules compared to other areas. These micro-propagules could serve as the 'seed' source of green tides. Their distribution patterns indicate that the green tide in the coastal areas of Qinhuangdao originated locally. | Hongbin Han Wei Song Zongling Wang Dewen Ding Chao Yuan Xuelei Zhang Yan Li | 2019 | Acta Oceanologica Sinica2019，38，8： | 8 |
| 9 | Stable isotope labelled mass spectrometry for quantification of the relative abundances for expressed proteins induced by PeaT1显示文摘The protein elicitor from the mycelium of Alternaria tenuissima has been isolated.The elicitor triggered resistance to the tobacco mosaic virus in tobacco by inducing relative oxygen species,but without causing hypersensitive necrosis.The elicitor is reported to impart resistance against Verticillium dahliae and to increase yield in cotton,but its mechanism is not yet clear.In this study,the stable isotope labelled mass spectrometry method was used to quantify the relative abundances of protein expression induced by PeaT1 in Arabidopsis.A significant difference in the relative abundances for the expression of different proteins related to metabolism,modification,regulatory,defense,stress and antioxidation was found in Arabidopsis. | LI GuangYue,YANG XiuFen,ZENG HongMei,MAO JianJun,LIU Hua,ZHANG YunHua & QIU DeWen* Key Laboratory for Biological Control of the Ministry of Agriculture,Institute of Plant Protection,Chinese Academy of Agricultural Sciences,Beijing 100081,China | 2010 | Science China(Life Sciences)2010，53，12： | 7 |
| 10 | Effect of Direct Quenching on Microstructure and Mechanical Properties of a Wear-resistant Steel显示文摘A wear-resistant steel was hot rolled at the same finish temperature,and subsequently treated with conventional reheat quenching and tempering process(RQ&T) and direct quenching and tempering process(DQ&T),respectively.The effect of direct quenching on the microstructure and mechanical properties was investigated in detail by using optical microscope,transmission electron microscope and scanning electron microscope equipped with electron backscattered diffraction.The results showed that the microstructures of both the RQ and DQ specimens were complex constituents of lath martensite and lower bainite.Compared with the RQ specimen,the lower bainite content in DQ specimen was much higher.Furthermore,the bainite in the DQ specimen extended into and segmented the prior austenite grains,which can decrease martensite packet size.The proportion of high-angle boundary in the DQ specimen was higher than that in the RQ specimen,which may improve the impact toughness.The carbides in DQ&T specimen were much finer and distributed even dispersively because direct quenching can retain substantive defects which may provide more nucleation sites for carbide precipitation in the tempering process.Besides,the mechanical properties of DQ and DQ&T specimens were superior than those subjected to RQ and RQ&T processes,respectively. | Hongyu SONG Shunhu ZHANG Liangyun LAN Canming LI Haitao LIU Dewen ZHAO Guodong WANG | 2013 | Acta Metallurgica Sinica(English Letters)2013，26，4： | 7 |
| 11 | Scene recognition combining structural and textural features显示文摘Automatic recognition of the contents of a scene is an important issue in the field of computer vision. Although considerable progress has been made, the complexity of scenes remains an important challenge to computer vision research. Most previous approaches for scene recognition are based on the so-called 'bag of visual words' model, which uses clustering methods to quantize numerous local region descriptors into a codebook. The size of the codebook and the selection of initial clustering centers greatly affect the performance. Furthermore, the large size of the codebook leads to high computational costs and large memory consumption. To overcome these weaknesses, we present an unsupervised natural scene recognition approach that is not based on the 'bag of visual words' model. This approach constructs multiple images of different resolutions and extracts structural and textural features from these images. The structural features are represented by weighted histograms of the gradient orientation descriptor, which is presented in this paper, and the textural features are represented by filter responses of Gabor filters and a Schmid set. We regard the structural and textural features as two independent feature channels, and combine them to realize automatic categorization of scenes using a support vector machine. We then evaluated our approach using three commonly used datasets with various scene categories. Our experiments demonstrate that the weighted histograms of the gradient orientation descriptor outperform the classical scale invariant feature transform descriptor in natural-scene recognition, and our approach achieves good performance with respect to current state-of-the-art methods. | ZHOU Li HU DeWen ZHOU ZongTan | 2013 | Science China(Information Sciences)2013，56，7： | 7 |
| 12 | Separation and recovery of scandium and titanium from red mud leaching liquor through a neutralization precipitation-acid leaching approach显示文摘Selective recovery of scandium and titanium from red mud leaching solution was achieved through neutralization precipitation followed by acid leaching approach.In the neutralization precipitation section,the effects of pH,temperature and reaction time on metal precipitation efficiency were investigated.Under the optimal co ndition,the precipitation efficiencies of scandium and titanium were 93.74%and 99.47%,respectively.In the acid leaching section,the effects of acidity,temperature,reaction time,and raffinate to acid solution ratio on leaching efficiency were investigated.Under the optimal condition,the leaching efficiencies of scandium and titanium were 99.97%and 5.44%,respectively.The loss of scandium and titanium were 6.3%and 5.9%,respectively.Compared with the traditional extraction procedure of scandium in red mud,this method could separate titanium from scandium effectively,which is beneficial for the purification of the products and improvement of value of the metal. | Qingyuan Lei Dewen He Kanggen Zhou Xuekai Zhang Changhong Peng Wei Chen | 2021 | Journal of Rare Earths2021，39，9： | 7 |
| 13 | Iterative freeform lens design for optical field control显示文摘It is still very challenging to determine a freeform lens for converting a given input beam into a prescribed output beam where not only the irradiance distribution but also the phase distribution hardly can be expressed analytically.Difficulties arise because the ray mapping from the input beam to the output beam is not only intertwined with the required double freeform surfaces but also intertwined with the output phase distribution,whose gradient represents the directions of the output rays.Direct determination of such a problem is very difficult.Here,we develop a special iterative wavefront tailoring(IWT)method to tackle this problem.In a certain iteration,the current calculation data of the double freeform surfaces and the output phase gradient are used to update the coefficients of a Monge–Ampère equation describing an intermediate wavefront next to the entrance freeform surface.The solution to the wavefront equation could lead to an improved ray mapping to be used to update the corresponding phase gradient data and reconstruct the double freeform surfaces.In a demonstrative example that deviates much from the paraxial or small-angle approximation,the new IWT method can generate a freeform lens that performs much better than that designed by a conventional ray mapping method for producing two irradiance distributions in the forms of numerals'1'and'2'on two successive targets,respectively. | ZEXIN FENG DEWEN CHENG YONGTIAN WANG | 2021 | Photonics Research2021，9，9： | 7 |
| 14 | The role of new energy in carbon neutral显示文摘Carbon dioxide is an important medium of the global carbon cycle,and has the dual properties of realizing the conversion of organic matter in the ecosystem and causing the greenhouse effect.The fixed or available carbon dioxide in the atmosphere is defined as'gray carbon',while the carbon dioxide that cannot be fixed or used and remains in the atmosphere is called'black carbon'.Carbon neutral is the consensus of human development,but its implementation still faces many challenges in politics,resources,technology,market,and energy structure,etc.It is proposed that carbon replacement,carbon emission reduction,carbon sequestration,and carbon cycle are the four main approaches to achieve carbon neutral,among which carbon replacement is the backbone.New energy has become the leading role of the third energy conversion and will dominate carbon neutral in the future.Nowadays,solar energy,wind energy,hydropower,nuclear energy and hydrogen energy are the main forces of new energy,helping the power sector to achieve low carbon emissions.'Green hydrogen'is the reserve force of new energy,helping further reduce carbon emissions in industrial and transportation fields.Artificial carbon conversion technology is a bridge connecting new energy and fossil energy,effectively reducing the carbon emissions of fossil energy.It is predicted that the peak value of China’s carbon dioxide emissions will reach 110×10^(8) t in 2030.The study predicts that China’s carbon emissions will drop to 22×10^(8) t,33×10^(8) t and 44×10^(8) t,respectively,in 2060 according to three scenarios of high,medium,and low levels.To realize carbon neutral in China,seven implementation suggestions have been put forward to build a new'three small and one large'energy structure in China and promote the realization of China’s energy independence strategy. | ZOU Caineng XIONG Bo XUE Huaqing ZHENG Dewen GE Zhixin WANG Ying JIANG Luyang PAN Songqi WU Songtao | 2021 | Petroleum Exploration and Development2021，48，2： | 6 |
| 15 | Design and manufacture AR head-mounted displays:A review and outlook显示文摘Augmented reality head-mounted displays(AR-HMDs)enable users to see real images of the outside world and visualize virtual information generated by a computer at any time and from any location,making them useful for various applications.The manufacture of AR-HMDs combines the fields of optical engineering,optical materials,optical coating,precision manufacturing,electronic science,computer science,physiology,ergonomics,etc.This paper primarily focuses on the optical engineering of AR-HMDs.Optical combiners and display devices are used to combine real-world and virtual-world objects that are visible to the human eye.In this review,existing AR-HMD optical solutions employed for optical combiners are divided into three categories:optical solutions based on macro-,micro-,and nanooptics.The physical principles,optical structure,performance parameters,and manufacturing process of different types of AR-HMD optical solutions are subsequently analyzed.Moreover,their advantages and disadvantages are investigated and evaluated.In addition,the bottlenecks and future development trends in the case of AR-HMD optical solutions are discussed. | Dewen Cheng Qiwei Wang Yue Liu Hailong Chen Dongwei Ni Ximeng Wang Cheng Yao Qichao Hou Weihong Hou Gang Luo Yongtian Wang | 2021 | Light(Advanced Manufacturing)2021，2，3： | 6 |
| 16 | Fault-Growth Pattern of the South Margin Normal Fault of the Yuguang Basin in Northwest Beijing and its Influencing Factors显示文摘Based on high-resolution remote sensing image interpretation, digital elevation model 3-D analysis, field geologic field investigation, trenching engineering, and ground-penetrating radar, synthetic research on the evolution of the Yuguang Basin South Margin Fault (YBSMF) in northwest Beijing was carried out. We found that the propagation and growth of faults most often occurred often at two locations: the fault overlapping zone and the uneven or rough fault segment. Through detailed observation and analysis of all cropouts of faults along the YBSMF from zone a to zone i, we identified three major factors that dominate or affect fault propagation and growth. First, the irregularity of fault geometry determine the propagation and growth of the fault, and therefore, the faults always propagate and grow at such irregular fault segments. The fault finally cuts off and eliminates its irregularity, making the fault geometry and fault plane smoother than before, which contributes to the slipping movement of the half-graben block in the basin. Second, the scale of the irregularity of the fault geometry affects the result of fault propagation and growth, that is, the degree of the cutting off of fault irregularity. The degree of cutting off decreases as irregularity scale increases. Third, the maximum possible slip displacement of the fault segment influences the duration of fault propagation and growth. The duration at the central segments with a large slip displacement is longer than that at the end segments with a smaller slippage value. | WANG Lin TIAN Qinjian LI Dewen ZHANG Xiaoliang | 2013 | Acta Geologica Sinica(English Edition)2013，87，3： | 6 |
| 17 | Magnetic labeling of natural lipid encapsulations wit ron-based nanoparticles显示文摘 | Dewen Ye Yan Li Ning Gu | 2018 | Nano Research2018，11，6： | 6 |
| 18 | The discovery and environmental significance of Chifeng wind route and huge pots of Inner Mongolia and Hebei Province显示文摘The pots discovered in Inner Mongolia and Hebei Province are huge with a maximum diameter of 9 m and a depth of 3.5 m, singular in shape,caused by weathering and wind erosion and have certain direction. They are a kind of typical climatic geomorphology. This | Zhijiu Cui Hongjiang Li Ling Nan Dewen Li | 1999 | Chinese Science Bulletin1999，44，16： | 5 |
| 19 | Freeform OST-HMD system with large exit pupil diameter and vision correction capability显示文摘Compactness and light weight,large exit pupil diameter and distance,small distortion for virtual image,and see-through light paths are pivotal factors to achieve a better,wearable experience of optical see-through headmounted displays(OST-HMDs).In addition,light efficiency of the virtual image light path is an important factor for heat dissipation in HMD devices.This paper presents a new type of OST-HMD optical system that includes three wedge-shaped freeform prisms and two symmetric lenses.Based on a 0.71 in.microdisplay,an OST-HMD prototype with a diagonal field of view(FOV)of 45.3°,an F-number(F/#)of 1.8,an exit pupil size of 12 mm×8 mm,and an eye relief of 18 mm is demonstrated.The maximum value of distortion of the final system is 0.6%and 0.4%for virtual image and see-through light path,respectively.The overall dimension of the optical system per eye is no larger than 30 mm(width)×40 mm(height)×14 mm(thickness),and the weight of the optical module including lenses,holder,and microdisplay is 12.8 g.The light efficiency of the virtual image light path is up to 50%higher than those of other OST-HMD optical solutions. | DEWEN CHENG JIAXI DUAN HAILONG CHEN HE WANG DANYANG LI QIWEI WANG QICHAO HOU TONG YANG WEIHONG HOU DONGHUA WANG XIAOYU CHI BIN JIANG YONGTIAN WANG | 2022 | Photonics Research2022，10，1： | 5 |
| 20 | Measures for controlling large deformations of underground caverns under high in-situ stress condition--A case study of JinpingⅠhydropower station显示文摘The Jinping Ⅰ hydropower station is a huge water conservancy project consisting of the highest concrete arch dam to date in the world and a highly complex and large underground powerhouse cavern.It is located on the right bank with extremely high in-situ stress and a few discontinuities observed in surrounding rock masses.The problems of rock mass deformation and failure result in considerable challenges related to project design and construction and have raised a wide range of concerns in the fields of rock mechanics and engineering.During the excavation of underground caverns,high in-situ stress and relatively low rock mass strength in combination with large excavation dimensions lead to large deformation of the surrounding rock mass and support.Existing experiences in excavation and support cannot deal with the large deformation of rock mass effectively,and further studies are needed.In this paper,the geological conditions,layout of caverns,and design of excavation and support are first introduced,and then detailed analyses of deformation and failure characteristics of rocks are presented.Based on this,the mechanisms of deformation and failure are discussed,and the support adjustments for controlling rock large deformation and subsequent excavation procedures are proposed.Finally,the effectiveness of support and excavation adjustments to maintain the stability of the rock mass is verified.The measures for controlling the large deformation of surrounding rocks enrich the practical experiences related to the design and construction of large underground openings,and the construction of caverns in the Jinping Ⅰ hydropower station provides a good case study of large-scale excavation in highly stressed ground with complex geological structures,as well as a reference case for research on rock mechanics. | Shengwu Song Xuemin Feng Chenggang Liao Dewen Cai Zhongxu Liu Yunhao Yang | 2016 | Journal of Rock Mechanics and Geotechnical Engineering2016，8，5： | 5 |
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