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| 1 | Further support for a Cretaceous age for the feathered-dinosaur beds of Liaoning,China:New ^(40)Ar/^(39)Ar dating of the Yixian and Tuchengzi Formations显示文摘We report new 40Ar/39Ar dating results ob-tained from total fusion and incremental-heating analyses of sanidine and biotite from three tuffs found interbedded within the fossil-bearing deposits of Liaoning, northeast China. The first is a new sample of the Bed 6 Sihetun tuff from the Yixian Formation, previously dated by our team as middle Early Cretaceous, and recently considered by Lo et al., partially reset due to metamorphism from a nearby ba-saltic sill. The second is the Yixian Bed 9 tuff from Heng-daozi considered by Lo et al. to be unaffected by metamor-phism and whose age, based on total fusion 40Ar/39Ar dating of biotite, argues for a Jurassic age for the Yixian Formation. The third tuff is a previously undated tuff from the upper part of the underlying Tuchengzi Formation. Single crystal total fusion 40Ar/39Ar analyses of the Sihetun sanidine showed homogeneous radiogenic Ar, Ca/K ratios, excellent reproducibility and gave a mean age of 125.0 ± 0.18 (1SD) ± 0.04 (SE) Ma. Single sanidine | C. C. Swisher III, WANG Xiaolin, ZHOU Zhonghe, WANG Yuanqing, JIN Fan, ZHANG Jiangyong , XU Xing, ZHANG Fucheng & WANG YuanDepartment of Geological Sciences, Wright Labs, Rutgers University, Piscataway, New Jersey 08854, USA (e-mail: cswish@rutgers. rci.e | 2002 | Chinese Science Bulletin2002，47，2： | 83 |
| 2 | Tea aroma formation显示文摘Besides water,tea is one of the most popular beverages around the world.The chemical ingredients and biological activities of tea have been summarized recently.The current review summarizes tea aroma compounds and their formation in green,black,and oolong tea.The flavor of tea can be divided into two categories:taste(non-volatile compounds)and aroma(volatile compounds).All of these aroma molecules are generated from carotenoids,lipids,glycosides,etc.precursors,and also from Maillard reaction.In the current review,we focus on the formation mechanism of main aromas during the tea manufacturing process.©2015 Beijing Academy of Food Sciences.Production and hosting by Elsevier B.V.All rights reserved. | Chi-Tang Ho Xin Zheng Shiming Li | 2015 | Food Science and Human Wellness2015，4，1： | 62 |
| 3 | SHRIMP zircon U-Pb geochronology of early Mesozoic felsic igneous rocks from the southern Lancangjiang and its tectonic implications显示文摘The SHRIMP zircon U-Pb geochronology of three typical samples, including two monzo nitic granites from the Lincang batholith and a rhyolite from the Manghuai Formation are presented in the southern Lancangjiang, western Yunnan Province. The analyses of zircons for the biotite monzonitic granites from the northern (02DX-137) and southern (20JH-10) Lincang batholith show the single and tight clusters on the concordia, and yield the weighted mean 206Pb/238U ages of 229.4 ± 3.0 Ma and 230.4 ± 3.6 Ma, respectively, representing the crystallized ages of these granites. The zircons for the rhyolitic sample (02DX-95) from the Manghuai Formation give a weighted mean 206Pb/238U age of 231.0 ± 5.0 Ma. These data suggest that the igneous rocks from the Lincang granitic batholith and Manghuai Formation have a similar crystallized age. In combination with other data, it is inferred that both were generated at a narrow age span (~230 Ma) and were originated from the postcollisional tectonic regime. An early Proterozoic 206Pb/238U apparent age of 1977±44 Ma is additionally obtained from one zircon from the biotite monzonitic granite (southern Lincang batholith), indicative of devel- opment of the early Proterozoic Yangtze basement in the region. These precisely geochronological data provide important constraints on better understanding the Paleozoic tectonic evolution of the Tethys, western Yunnan Province. | PENG Touping1,2, WANG Yuejun1, FAN Weiming1, LIU Dunyi3, SHI Yuruo3 & MIAO Laicheng4 1. Key Laboratory of Isotope Geochronology and Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China 2. Graduate University of Chinese Academy of Sciences, Beijing 100039, China 3. SHRIMP isotope Laboratory, Chinese Academy of Geological Sciences, Beijing 100037, China 4. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China | 2006 | Science China Earth Sciences2006，49，10： | 55 |
| 4 | The compositions,sources,and size distribution of the dust storm from China in spring of 2000 and its impact on the global environment显示文摘The average mass concentration of the aerosols in Beijing during the dust storm in the spring of 2000 was -6000 μg · m-3, -30 times as high as that in the non-dust storm days. The enrichment factors of the pollution elements As, Sb and Se were higher than those in the non-dust storm days. This indicated that As, Sb and Se resulted from the pollution sources of those areas, through which the dust storm passed during their long-range transport, in addition to the local pollution sources in Beijing. The enrichment factors of the Pb, Zn, Cd and Cu were much less than those in the non-dust storm days, suggesting that the local pollution sources in Beijing area contributed to them mostly. The enrichment factors of elements Al, Fe, Sc, Mn, Na, Ni, Cr, V and Co were close to 1, showing that these elements originated from crust. The concentration of S in the dust storm was -10 μg · m-3,4 times as high as that in non-dust storm. S in the aerosols resulted from the adsorption of gaseous SO2 and the consequent | Guoshun Zhuang Jinghua Guo Hui Yuan Chengyi Zhao | 2001 | Chinese Science Bulletin2001，46，11： | 44 |
| 5 | A nearly completely articulated rhamphorhynchoid pterosaur with exceptionally well-preserved wing membranes and 'hairs' from Inner Mongolia, northeast China显示文摘We report a new and nearly completely articu-lated rhamphorhynchoid pterosaur, Jeholopterus ningchen-gensis gen. et sp. nov., with excellently preserved fibres in the wing membrane and 'hairs' in the neck, body and tail re-gions. Many of its characteristics such as a short neck, short metacarpals and distinctively long fifth pedal digit are char-acteristic of rhamphorhynchoids. The new species can be further referred to the ’strange’ short-tailed rhamphorhyn-choid family Anurognathidae. It is much more complete than the other known members of the family, namely, Anurog-nathus from Solnhofen, Germany, Batrachognathus from Karatau, Kazakhstan, and Dendrorhynchoides from Beipiao, Liaoning Province, China. The new pterosaur also shows that the wing membrane is attached to the ankle of the hind limb. The pedal digits are webbed. Furthermore, the 'hair' of Jeholopterus bears some resemblance to the hair-like in-tegumental structures of the feathered dinosaur Sinosaurop-teryx although there is yet no direct | Xiaolin Wang Zhonghe Zhou Fucheng Zhang Xing Xu | 2002 | Chinese Science Bulletin2002，47，3： | 37 |
| 6 | Two new ornithurine birds from the Early Cretaceous of western Liaoning,China显示文摘We describe two new ornithurine birds from the Early Cretaceous Jiufotang Formation of western Liaoning, northeast China: Yanornis martini gen. et sp. nov. and Yixianornis grabaui gen. et sp. nov. They represent the best fossil record of ornithurine birds known from the Early Cretaceous. They are more advanced than the most primitive ornithurine Liaoningornis, and are more similar to the other two Chinese Early Cretaceous ornithurines Chaoyangia and Songlingornis. Compared with Confuciusornis, Liaoxiornls and Eoenantiornis from the same age, the two new birds show remarkable advanced characteristics and suggest the presence of powerful flight capability like modern birds. Compared with Yixianornis and Chaoyangia, Yanornis is larger, with a more elongated skull and relatively long wings. The new discoveries indicate that by the Early Cretaceous both enantiornithine and ornithurine birds had already radiated significantly. The flight structures of Yanornis and Yixianornis are hardly distinguishable from | Zhonghe Zhou Fucheng Zhang | 2001 | Chinese Science Bulletin2001，46，15： | 36 |
| 7 | Phosphogypsum stabilization of bauxite residue:Conversion of its alkaline characteristics显示文摘Reduction of the high alkalinity of bauxite residue is a key problem to solve to make it suitable for plant growth and comprehensive utilization. In this study, phosphogypsum, a waste product from the phosphate fertilizer industry, was used to drive the alkaline transformation of the bauxite residue. Under optimal water washing conditions(liquid/solid ratio of 2 mL/g, 30°C, 24 hr), the impact of quantity added, reaction time and reaction mechanism during phosphogypsum application were investigated. Phosphogypsum addition effectively lowered p H levels and reduced the soluble alkalinity by 92.2%. It was found that the concentration of soluble Na and Ca ions in the supernatant increased gradually, whilst the exchangeable Na+and Ca^(2+)in solid phase changed 112 mg/kg and 259 mg/kg, respectively. Ca^(2+)became the dominant element in the solid phase(phosphogypsum addition of 2%, liquid/solid ratio of 2 mL/g, 30°C, 12 hr). X-ray diffraction data indicated that cancrinite and hydrogarnet were the primary alkaline minerals. SEM images suggested that phosphogypsum could promote the formation of stable macroaggregates, whilst the content of Ca^(2+)increased from 5.6% to 18.2% and Na reduced from 6.8% to 2.4%. Treatment with phosphogypsum could significantly promote the transformation of alkalinity cations by neutralization, precipitation and replacement reactions.This research provided a feasible method to promote soil formation of bauxite residue by phosphogypsum amendment. | Shengguo Xue Meng Li Jun Jiang Graeme J.Millar Chuxuan Li Xiangfeng Kong | 2019 | Journal of Environmental Sciences2019，31，3： | 35 |
| 8 | Structural pattern of eastern Himalayan syntaxis in Namjagbarwa and its formation process显示文摘The structural pattern of the eastern Himalayan syntaxis in Namjagbarwa consists of two series of structures with different styles. One series compiles the earlier ductile contractional and lateral-slip deformation system, formed by nearly north-south shortening within the syntaxis, left-lateral and right-lateral slipping along its western and eastern boundaries respectively. They were possibly produced by the indentation of the Indian continent into Asian continent after India-Asia collision. The peak deformation-metamorphic ages in these structures are 62-60 Ma, ~23 Ma and ~13 Ma. The other series is composed of ductile-brittle normal faults distributing concentrically and dipping toward the outsides of Namjagbarwa Peak. They were probably the collapse structures caused by rapid uplift in a later time and the beginning ages for the normal faulting are about 7.3-6.3 Ma. | ZHANG Jinjiang, Jl Jianqing, ZHONG Dalai, DING Lin & HE Shundong1. Department of Geology, Peking University, Beijing 100871, China 2. Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China Correspondence should be addressed to Zhang Jinjiang (email: zhjj@pku.edu.cn) | 2004 | Science China Earth Sciences2004，47，2： | 34 |
| 9 | Mechanism of the Spring Persistent Rains over southeastern China显示文摘The Spring Persistent Rains (SPR) in the areas to the south of middle and lower reaches of the Yangtze River or over southeastern China (SEC) is a unique synoptic and climatic phenomenon in East Asia. This study reveals a possible mechanism responsible for the climatic cause of SPR formation through climatic mean data analysis and sensitive numerical model experiments. SEC is located at the down-stream of the southwesterly velocity center (SWVC) which lies on the southeastern flank of the Tibetan Plateau (TP). As a result, there are strong southwesterly wind velocity convergence and moisture con-vergence over SEC. This is the immediate climatic cause of SPR formation. In spring, the seasonal evolution of the southwesterly velocity consists with the surface sensible heating over southeastern TP, indicating that the formation of SPR is related to not only the southwesterly wind of mechanical de-flected flow of TP, but also the southwesterly wind of thermal-forced cyclonic low circulation. Sensitive numerical experiments demonstrate that, without TP, both SWVC and the SPR rain belt will disappear. The southwesterly wind velocity increases almost linearly with the amount of the total diabatic heating with TP rising. Therefore, SWVC is the result of the mechanical forcing and thermal forcing of TP. All these strongly suggest that the presence of TP plays a primary role in the climatic formation of SPR. | WAN RiJin1,2,3 & WU GuoXiong1 1 State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Mechanicals (LASG), Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing 100029, China 2 Guangdong Climate and Agrometeorology Center, Guangzhou 510080, China 3 Shanghai Typhoon Institute of China Meterological Administration, Shanghai 200030, China | 2007 | Science China Earth Sciences2007，50，1： | 34 |
| 10 | Ordovician graptolite-bearing strata in southern Jiangxi with a special reference to the Kwangsian Orogeny显示文摘The Ordovician graptolite sequence of the Yongxin-Chongyi area in southern Jiangxi was suggested as a standard for the correlation of Ordovician in the Zhujiang region of South China. Based on a restudy of the Upper Ordovician graptolites, the Shikou and Huamianlong formations are recognized herein as a part of the Hanjiang Formation, corresponding only to the Dipla-canthograptus caudatus-Diplacanthograptus spiniferus Zone. Two graptolite zones in the Longxi Formation of Yongxin and Chongyi, the Nemagraptus gracilis Zone and Climacograptus bicornis Zone, are redefined here. A rapid replacement of facies from the typical deep-water graptolitic black shale of Longxi Formation to the rapidly-accumulated, shallow-water clastic deposits of Hanjiang Formation indicates the tectonic initiation of the Kwangsian Orogeny. The thick clastic deposits of the Han-jiang Formation are proposed to come from a nearby source area that rose during the Kwangsian Orogeny. The D. caudatus-D. spiniferus graptolite Zone of the Hanjiang Formation indicates the initiation time of this tectonic event. | Xu Chen YuanDong Zhang JunXuan Fan JunFeng Cheng QiJian Li | 2010 | Science China Earth Sciences2010，53，11： | 29 |
| 11 | Diagenetic fluids evolution and genetic mechanism of tight sandstone gas reservoirs in Upper Triassic Xujiahe Formation in Sichuan Basin, China显示文摘The reservoirs of the Upper Triassic Xujiahe Formation in Sichuan Basin have the characteristics of low compositional maturity, low contents of cements and medium textural maturity. The general physical properties of the reservoirs are poor, with low porosity and low permeability, and there are only a few reservoirs with medium porosity and low permeability in local areas. Based on the diagenetic mineral association, a diagenetic sequence of cements is established: early calcites (or micrite siderites) →first quartz overgrowth→chlorite coatings→dissolution of feldspars and debris→chlorite linings→ second quartz overgrowth (quartz widen or filled in remain intergranular pores and solution pores)→dissolution→third quartz overgrowth (quartz filled in intergranular and intragranular solution pores)→intergrowth (ferro) calcites→dolomites→ferro (calcites) dolomites→later dissolution→veins of quartz and calcites formation. Mechanical compaction is the main factor in making the reservoirs tight in the basin, followed by the second and third quartz overgrowth. In a long-term closed system, only feld-spars and some lithic fragments are dissolved by diagenetic fluids, while intergranular cements such as quartz and calcit are not dissolved and thus have little influence on the porosity of the Xujiahe Formation. This is the third factor that may have kept the sandstones of Xujiahe Formation tight finally. The hydrocarbon was extensively generated from organic materials after the second quartz overgrowth, and selectively entered favorable reservoirs to form tight sandstone gas reservoirs. | ZHU RuKai ZOU CaiNeng ZHANG Nai WANG XueSong CHENG Rong LIU LiuHong ZHOU ChuanMin SONG LiHong | 2008 | Science China Earth Sciences2008，51，9： | 29 |
| 12 | Characteristics of volatile organic compounds,NO_2,and effects on ozone formation at a site with high ozone level in Chengdu显示文摘Chengdu is a megacity in the southwest of China with high ozone(O_3) mixing ratio.Observation of volatile organic compounds(VOCs), NO_2 and O_3 with high temporal resolution was conducted in Chengdu to investigate the chemical processes and causes of high O_3 levels. The hourly mixing ratios of VOCs, NO2, and O_3 were monitored by an online system from 28 August to 7 October, 2016. According to meteorological conditions,Chengdu, with relative warm weather and low wind speed, is favorable to O_3 formation.Part of the O_3 in Chengdu may be transported from the downtown area. In O_3 episodes,the average mixing ratios of NO_2 and O_3 were 20.20 ppbv and 47.95 ppbv, respectively. In non-O_3 episodes, the average mixing ratios of NO_2 and O_3 were 16.38 ppbv and 35.15 ppbv,respectively. The average mixing ratio of total VOCs(TVOCs) was 40.29 ppbv in non-O_3 episodes, which was lower than that in O_3 episodes(53.19 ppbv). Alkenes comprised51.7% of the total O_3 formation potential(OFP) in Chengdu, followed by aromatics which accounted for 24.2%. Ethylene, trans-pentene, propene, and BTEX(benzene, ethylbenzene,toluene, m/p-xylene, o-xylene) were also major contributors to the OFP in Chengdu. In O_3 episodes, intensive secondary formations were observed during the campaign. Oxygenated VOCs(OVOCs), such as acetone, Methylethylketone(MEK), and Methylvinylketone(MVK)were abundant. Isoprene rapidly converted to MVK and Methacrolein(MACR) during O_3 episodes. Acetone was mainly the oxidant of C3-C5 hydrocarbons. | Yuanyuan Deng Jing Li Yaqi Li Rongrong Wu Shaodong Xie | 2019 | Journal of Environmental Sciences2019，31，1： | 29 |
| 13 | PHYSICAL MODELING FOR THE MECHANISMS OF BEAD FORMATION DEFECTS BASED ON THE STABILITY OF LIQUID METAL显示文摘Based on the theory of stability of the liquid metal under the action of surface tension,a physical mod- el is established for the mechanisms of the bead formation deferct’ humping’, which is generated during high - speed welding.A boundary function is introduced to correct the model,theoretical results got by the model correspond well with the experimental phenomena. A two - dimensional conducting model is adoopted in the simulation of the temperature field during high - speed welding.Finally, the factors acting upon the stability of liquid metal are analyzed. | S. Y. Yin L. Feng J. Z. Ding and S. J. Chan( 1) Beijing Polytechnic University, Beijing 100022, China 2) National Key Laboratory of Advanced Wdlding Production Technology, HIT, Harbin 150001, China) | 2000 | Acta Metallurgica Sinica(English Letters)2000，13，1： | 28 |
| 14 | Characteristics of one-year observation of VOCs,NOx, and O_3 at an urban site in Wuhan, China显示文摘A continuous online observation of ozone and its precursors(NOx, VOCs) was carried out in central urban Wuhan from September 2016 to August 2017. The concentration levels of ozone,NOx, VOCs and their variations in urban Wuhan were analyzed, as well as effects of VOCs on ozone photochemical generation and the main controlling factors for ozone production. During the observation period, the average concentrations of ozone and NOx in Wuhan was 22.63 and30.14 ppbv, respectively, and the average concentration of VOCs was 32.61 ppbv(42.3% alkanes,13.0% alkenes, 10.0% aromatics, 7.3% acetylene, 9.9% OVOCs, and 10.5% halohydrocarbons).Ozone concentration was higher in spring and summer as compared with autumn and winter,wheras VOCs and NOx concentratios were lower in spring and summer but higher in autumn and winter. Aromatics and alkenes, two of VOCs species, showed the highest contributions to ozone formation potential in Wuhan(35.7% alkenes, 35.4 aromatics, 17.5% alkanes, 8.6% OVOCs,1.6% halogenated hydrocarbons, and 1.4% acetylene). Among all VOCs species, those with the highest contribution were ethylene, m-xylene, toluene, propylene and o-xylene. The contribution of these five compounds to the total ozone formation potential concentration was 43.90%.Ozone-controlling factors in Wuhan changed within one day; during the early morning hours(6:00–9:00), VOCs/NOx was low, and ozone generation followed a VOCs-limited regime.However, during the peak time of ozone concentration(12:00–16:00), the ratio of VOCs/NOx was relatively high, suggesting that ozone generation followed a NOx-limited regime. | Yichang Yang Xingang Liu Jun Zheng Qinwen Tan Miao Feng Yu Qu Junling An Nianliang Cheng | 2019 | Journal of Environmental Sciences2019，31，5： | 26 |
| 15 | A NUMERICAL STUDY ON THE FORMATION AND DEVELOPMENT OF ISLAND-INDUCED CYCLONE AND ITS IMPACT ON TYPHOON STRUCTURE CHANGE AND MOTION显示文摘In this paper,the impact of the Taiwan Island topography on the structure change and motion ofTyphoon Dot(9017)during its crossing the Taiwan Island is studied with a modified version of aJMA operational regional model(Japan spectral model,JSM).A series of sensitivity experiments areconducted to detect the forming and developing mechanism of an island-induced cyclone.Results showthat lee side low pressure center plays a very important role in the formation of the induced-cyclonewhile a typhoon is approaching a large island with high mountains.The position and intensity of theinduced cyclone is sensitive to the height and location of island mountain,intensity of TC and under-lying surface topography distribution as well.A preliminary formation criterion of the island-inducedcyclone is obtained. | 孟智勇 永田雅 陈联寿 | 1996 | Acta meteorologica Sinica1996，10，4： | 24 |
| 16 | RANKL signaling in bone marrow mesenchymal stem cells negatively regulates osteoblastic bone formation显示文摘RANKL signaling is essential for osteoclastogenesis. Its role in osteoblastic differentiation and bone formation is unknown. Here we demonstrate that RANK is expressed at an early stage of bone marrow mesenchymal stem cells(BMSCs) during osteogenic differentiation in both mice and human and decreased rapidly. RANKL signaling inhibits osteogenesis by promoting β-catenin degradation and inhibiting its synthesis. In contrast, RANKL signaling has no significant effects on adipogenesis of BMSCs.Interestingly, conditional knockout of rank in BMSCs with Prx1-Cre mice leads to a higher bone mass and increased trabecular bone formation independent of osteoclasts. In addition, rank^(flox/flox): Prx1-Cre mice show resistance to ovariectomy-(OVX) induced bone loss. Thus, our results reveal that RANKL signaling regulates both osteoclasts and osteoblasts by inhibition of osteogenic differentiation of BMSCs and promotion of osteoclastogenesis. | Xiao Chen Xin Zhi Jun Wang Jiacan Su | 2018 | Bone Research2018，6，4： | 24 |
| 17 | Geologic characteristics, controlling factors and hydrocarbon accumulation mechanisms of China’s Large Gas Provinces of low porosity and permeability显示文摘Based on the analysis of the geological characteristics and controlling factors, we analyzed the formation mechanism of different types of gas reservoirs. The main characteristics of gas provinces with low porosity and permeability are mainly as follows: large area, low abundance, small gas pools and large gas provinces; widely distributed excellent hydrocarbon source rocks with closely contacted source-reservoir-cap association; development mainly in large continental depressions or in paralic shallow-river delta systems; many kinds of traps coexisting in large areas, dominantly para-layered lithologic, digenetic and capillary pressure traps; double fluid flow mechanisms of Darcy flow and non-Darcy flow; complicated gas and water relations; and having the resource distribution of highly productive 'sweet spots', banding concentration, and macroscopically large areas integrated. The main controlling factors of large sandstone gas provinces with low porosity and permeability are stable dynamic backgrounds and gentle structural frameworks which control the extensive distribution of alternate (interbedded) sandstones and mudstones; weak hydropower of large gentle lake basins controlling the formation of discontinuous, low porosity and permeability reservoirs in shallow-water deltas; regionally differential diagenesis and no homogeneous digenetic facies controlling the development of favorable reservoirs and digenetic traps; and weak and dispersive reservoir-forming dynamic forces leading to the widely distributed small traps with low abundance. Low porosity and permeability gas provinces with different trap types have different formation mechanisms which include fluid diversion pressure difference interactive mechanism of lithologic-trap gas accumulations, separated differential collection mechanism of digenetic-trap gas accumulations, and the Non-Darcy flow mechanism of capillary-pressure gas accumulations. | ZOU CaiNeng TAO ShiZhen ZHANG XiangXiang HE DongBo ZHOU ChuanMin GAO XiaoHui | 2009 | Science China Earth Sciences2009，52，8： | 22 |
| 18 | Changes in distribution and microstructure of bauxite residue aggregates following amendments addition显示文摘Bauxite residue is a highly alkaline byproduct which is routinely discarded at residue disposal areas. Improving soil formation process to revegetate the special degraded lands is a promising strategy for sustainable management of the refining industry. A laboratory incubation experiment was used to evaluate the effects of gypsum and vermicompost on stable aggregate formation of bauxite residue. Aggregate size distribution was quantified by fractal theory, whilst residue microstructure was determined by scanning electron microscopy and synchrotron-based X-ray micro-computed tomography. Amendments addition increased the content of macro-aggregates(> 250 μm) and enhanced aggregate stability of bauxite residue. Following gypsum and vermicompost addition, fractal dimension decreased from 2.84 to 2.77, which indicated a more homogeneous distribution of aggregate particles. Images from scanning electron microscopy and three-dimensional microstructure demonstrated that amendments stimulate the formation of improved structure in residue aggregates. Pore parameters including porosity, pore throat surface area, path length, and path tortuosity increased under amendment additions. Changes in aggregate size distribution and microstructure of bauxite residue indicated that additions of gypsum and vermicompost were beneficial to physical condition of bauxite residue which may enhance the ease of vegetation. | Shengguo Xue Yuzhen Ye Feng Zhu Qiongli Wang Jun Jiang William Hartley | 2019 | Journal of Environmental Sciences2019，31，4： | 21 |
| 19 | Chronology and geochemistry of the volcanic rocks in Woruo Mountain region,Northern Qiangtang depression:Implications to the Late Triassic volcanic-sedimentary events显示文摘A suite of sedimentary-volcaniclastic rocks intercalated with the volcanic rocks unconformably overlies the Triassic Xiaochaka Formation in the Woruo Mountain region, Qiangtang Basin, northern Tibet. The vitric tuff from the base of these strata gives a SHRIMP zircon U-Pb age of 216 ± 4.5 Ma, which represents the age of the Late Triassic volcanic-sedimentary events in the Woruo Mountain region, and is consistent with that of the formation of the volcanic rocks from the Nadi Kangri Formation in the Nadigangri-Shishui River zone. There is a striking similarity in geochemical signatures of the volcanic rocks from the Woruo Mountain region and its adjacent Nadigangri-Shishui River zone, indicating that all the volcanic rocks from the Qiangtang region might have the same magmatic source and similar tectonic setting during the Late Triassic. The proper recognition of the Late Triassic large-scale volcanic eruption and volcanic-sedimentary events has important implications for the interpretation of the Late Triassic biotic extinction, climatic changes and regressive events in the eastern Tethyan domain, as well as the understanding of the initiation and nature, and sedimentary features of the Qiangtang Basin during the Late Triassic-Jurassic. | WANG Jian FU XiuGen CHEN WenXi WANG ZhengJiang TAN FuWen CHEN Ming ZHUO JieWen | 2008 | Science China Earth Sciences2008，51，2： | 21 |
| 20 | Coordinated flight control of miniature fixed-wing UAV swarms: methods and experiments显示文摘In this paper,we present our recent advances in both theoretical methods and field experiments for the coordinated control of miniature fixed-wing unmanned aerial vehicle(UAV)swarms.We propose a multi-layered group-based architecture,which is modularized,mission-oriented,and can implement large-scale swarms.To accomplish the desired coordinated formation flight,we present a novel distributed coordinated-control scheme comprising a consensus-based circling rendezvous,a coordinated path-following control for the leader UAVs,and a leader-follower coordinated control for the follower UAVs.The current framework embeds a formation pattern reconfiguration technique.Moreover,we discuss two security solutions(inter-UAV collision avoidance and obstacle avoidance)in the swarm flight problem.The effectiveness of the proposed coordinated control methods was demonstrated in field experiments by deploying up to 21 fixed-wing UAVs. | Xiangke WANG Lincheng SHEN Zhihong LIU Shulong ZHAO Yirui CONG Zhongkui LI Shengde JIA Hao CHEN Yangguan YU Yuan CHANG Yajing WANG | 2019 | Science China(Information Sciences)2019，62，11： | 21 |
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