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| 1 | Improving Yield and Nitrogen Use Efficiency Simultaneously for Maize and Wheat in China: A Review显示文摘同时完成两高收益和高氮使用效率(NUE ) 与对食物,自然资源的弄空,和环境的恶化的增加的全球需求成为了主要挑战。作为在世界上的 N 化肥的最伟大的消费者,中国农民滥用了 N,并且因为 N 举起收益关系的有限理解,在庄稼 N 需求和 N 供应之间有差的 synchrony。处理这个问题,这研究为二个学生的不同收益范围评估了全部、动态的 N 要求庄稼(玉米和小麦) ,和到 N 管理策略的建议改进。整个植物的 N 未葬举起要求每谷物产量(N req ) 开始与谷物收益改进死亡了然后停滞,并且然而,大多数农民仍然相信更多的化肥和更高的谷物产量是同义的。当玉米产量增加了从时 < 7.5 到 > 12.0 Mg 哈 −1, N req 从 19.8 ~ 17.0 kg Mg −1 谷物减少了。为小麦,它为谷物产量从 27.1 kg Mg −1 谷物减少了 < 4.5 Mg 哈 −1 到为产量的 22.7 kg Mg −1 谷物 > 9.0 Mg 哈 −1 。同时,干燥物质的百分比和在中间迟了的成长季节的 N 累积与谷物产量显著地增加了,它显示 N 授精应该在中间迟了的阶段被集中当农民们经常在播种前或在早生长阶段期间使用了 N 化肥的多数时,匹配庄稼需求。我们因此开发了同时增加谷物产量和 NUE 的综合土壤庄稼系统管理策略。 | MENG Qingfeng YUE Shanchao HOU Peng CUI Zhenling CHEN Xinping | 2016 | Pedosphere2016，26，2： | 51 |
| 2 | Cementation of sand grains based on carbonate precipitation induced by microorganism显示文摘Microbes can produce 2 3 CO_3^(2-)in an environment conductive to precipitation,so the incompact sands will be consolidated.This technology is environmentally friendly not only because it gives strength to the sand body,but also it allows water to penetrate into the sand body,which is unlike silicate cement that will destroy the ecosystem of the earth.After comparing the activity of three kinds of bacteria,the most suitable one was chosen for the study.However,the activity of this bacterium was still not high enough for the purpose,so it was purified.A suitable program for the consolidation and cementation of sands was also found in the experiment.The compressive strength and the porosity of the cemented sand body were tested to characterize the cementation effectiveness.XRD analysis showed that a new phase of calcite was produced between sand grains.The content of calcite was detected by TG.The study showed that the precipitation program was quite important to obtain a sound cemented sand body in addition to the activity of the bacteria. | QIAN ChunXiang,PAN QingFeng &WANG RuiXing Jiangsu Key Laboratory of Construction Materials,School of Materials Science&Engineering,Southeast University,Nanjing 211189,China | 2010 | Science China(Technological Sciences)2010，53，8： | 34 |
| 3 | The Inhibitory Effect of Oridonin on the Growth of Fifteen Human Cancer Cell Lines显示文摘OBJECTIVE To study the inhibitory effect of oridonin on the growth of cancer cells. METHODS Fifteen human cancer cell lines were subjected to various concentrations of oridonin in culture medium. The inhibitory rate of cell growth was measured by the MTT assay, and compared with a negative con- trol and 5-Fu-positive control. RESULTS The 50% inhibiting concentration (IC50) and maximal inhibition (Imax) of oridonin shown by studying the growth of the cancer cell lines were as follows: leukemias (HL60 cells: 3.9 μg/ml and 73.8%, K562 cells: 4.3 μg/ml and 76.2%); esophageal cancers(SHEEC cells: 15.4 μg/ml and 99.2%, Eca109 cells: 15.1 μg/ml and 84.6%, TE1 cells: 4.0 μg/ml and 70.2%); gastric cancers (BGC823 cells: 7.6 μg/ml and 98.7%, SGC7901 cells: 12.3 μg/ml and 85.7%); colon cancers (HT29 cells: 13.6 μg/ml and 97.2%, HCT cells: 14.5 μg/ml and 96.5%); liver cancers (Bel7402 cells: 15.2 μg/ml and 89.2%, HepG2 cells: 7.1 μg/ml and 88.3%); pancreatic cancer (PC3 cells: 11.3 μg/ml and 68.4%); lung cancer (A549 cells: 18.6 μg/ml and 98.0% ); breast cancer (MCF7 cells: 18.4 μg/ml and 84.7%); uterine cervix cancer (Hela cells: 13.7 μg/ml and 98.5%). CONCLUSION Oridonin had a relatively wide anti-tumor spectrum, and a relatively strong inhibitory effect on the growth of the 15 human cancer cells. Inhibitory effects were concentration dependent. | Junhui Chen Shaobin Wang Dongyang Chen Guisheng Chang Qingfeng Xin Shoujun Yuan Zhongying Shen | 2007 | Chinese Journal of Clinical Oncology2007，4，1： | 32 |
| 4 | Holocene vegetational and climatic variation in westerly-dominated areas of Central Asia inferred from the Sayram Lake in northern Xinjiang,China显示文摘Changes in the vegetation and climate of the westerly-dominated areas in Central Asia during the Holocene were interpreted using pollen-assemblages and charcoal data from a 300-cm-long sediment core of the Sayram Lake,northern Xinjiang.Accele-rator Mass Spectrometry(AMS) radiocarbon dating methods were applied to bulk organic matter of the samples.Artemisia spp./Chenopodiaceae ratios and results from principal component analysis were used to infer that the lake basin was dominated by desert vegetation before ca.9.6 cal.ka BP,which suggests a warm and dry climate in the early Holocene.Desert steppe/steppe expanded during 9.6-5.5 cal.ka BP,indicating a remarkable increase both in the precipitation and temperature during the mid-Holocene.Desert vegetation dominated between 6.5 and 5.5 cal.ka BP,marking an extreme warmer and drier interval.The steppe/meadow steppe recovered,and temperatures decreased from 5.5 cal.ka BP in the late Holocene,as indicated by the increased abundance of Artemisia and the development of meadows.Holocene temperatures and moisture variations in the Sayram Lake areas were similar to those of adjacent areas.This consistency implies that solar radiation was the main driving factor for regional temperature changes,and that the effect of temperature variations was significant on regional changes in humidity.The evolution of climate and environment in the Sayram Lake areas,which were characterized as dry in the early Holocene and relatively humid in the middle-late Holocene,are clearly different from those in monsoonal areas.Dry conditions in the early Holocene in the Sayram Lake areas were closely related to decreased water vapor advection.These conditions were a result of reduced westerly wind speeds and less evaporation upstream,which in turn were caused by seasonal changes in solar radiation superimposed by strong evaporation following warming and drying local climate. | JIANG QingFeng JI JunFeng SHEN Ji Ryo MATSUMOTO TONG GuoBang QIAN Peng REN XueMei YAN DeZhi | 2013 | Science China Earth Sciences2013，56，3： | 32 |
| 5 | A high-resolution climatic change since Holocene inferred from multi-proxy of lake sediment in westerly area of China显示文摘Multi-proxy data are presented and a discuss is made of paleoclimatic and paleoenvironmental changes during Holocene from a 225-cm-long sediment core from Wulungu Lake, located in westerly area of China. The chronology is constructed from six AMS radiocarbon dates on the bulk organic matter. Analyses of pollen, TOC, TN, δ 13Corg, ostracod assemblages and the shell stable isotopes, suggest Holocene climate pattern as follows: temperate and dry (10.0―7.6 cal. ka BP)-warm and wet (7.6―5.3 cal. ka BP) -warm and moist (5.3―3.6 cal. ka BP) -temperate and dry (3.6―2.1 cal. ka BP)-temperate and moist (2.1―1.3 cal. ka BP) -cool and dry (1.3 cal. ka BP―present). With the climatic change, Wulungu Lake experienced two large-scale retreat (5.3―3.6 cal. ka BP and 1.3 cal. ka BP―present) and an obvious transgression (7.6―5.3 cal. ka BP). The records of climatic and environmental evolution of Wulungu Lake were in good accordance with those of adjacent areas. It responded to regional environmental change, global abrupt climate events and followed the westerly climate change mode. | JIANG QingFeng SHEN Ji LIU XingQi ZHANG EnLou XIAO XiaYun | 2007 | Chinese Science Bulletin2007，52，14： | 28 |
| 6 | Hydraulic Accumulator-Motor-Generator Energy Regeneration System for a Hybrid Hydraulic Excavator显示文摘Though the traditional energy regeneration system(ERS) which used a hydraulic motor and a generator in hybrid excavators can regenerate part of the energy, the power of the motor and the generator should be larger and the time for regenerating energy is so short. At first, the structure of new ERS that combines the advantages of an electric and hydraulic accumulator is analyzed. The energy can be converted into both the electric energy and the hydraulic energy at the lowering of the boom and the generator can still works when the boom stops going down. Then, a method how to set the working pressure of the hydraulic accumulator is proposed. To avoid the excess loss, extra noise and shock pressure, a two-level pressure threshold method that the generator starts to work at the rising edge of the high pressure threshold and stops working at the falling edge of the low pressure threshold is presented to characterize the working mode of the generator. The control strategies on how to control the boom velocity at the lowering of the boom and how to improve the recovery efficiency when the boom stops going down are presented. The test bench of hybrid excavator with ERS is constructed, with which the studies on the influences of ERS on energy conversion efficiency and control performance are carried out. Experimental results show that the proposed ERS features better speed control performance of the boom than traditional ERS. It is also observed that an estimated 45% of the total potential energy could be regenerated at the lowering of the boom in the proposed ERS, and the power level of the generator and the hydraulic motor could be reduced by 60%. Hence, the proposed ERS has obvious advantages over the traditional ERS on the improvement of energy regeneration time, energy efficiency, control performance and economy. | LIN Tianliang WANG Qingfeng | 2012 | Chinese Journal of Mechanical Engineering2012，25，6： | 22 |
| 7 | A structural view of the conserved domain of rice stress-responsive NAC1显示文摘The importance of NAC(named as NAM,ATAF1,2,and CUC2)proteins in plant development,transcription regulation and regulatory pathways involving proteinprotein interactions has been increasingly recognized.We report here the high resolution crystal structure of SNAC1(stress-responsive NAC)NAC domain at 2.5Å.Although the structure of the SNAC1 NAC domain shares a structural similarity with the reported structure of the ANAC NAC1 domain,some key features,especially relating to two loop regions which potentially take the responsibility for DNA-binding,distinguish the SNAC1 NAC domain from other reported NAC structures.Moreover,the dimerization of the SNAC1 NAC domain is demonstrated by both soluble and crystalline conditions,suggesting this dimeric state should be conserved in this type of NAC family.Additionally,we discuss the possible NAC-DNA binding model according to the structure and reported biological evidences. | Qingfeng Chen Quan Wang Lizhong Xiong Zhiyong Lou | 2011 | Protein & Cell2011，2，1： | 18 |
| 8 | A Highly Pathogenic Strain of Porcine Deltacoronavirus Caused Watery Diarrhea in Newborn Piglets显示文摘Porcine deltacoronavirus(PDCoV) is a newly identified virus that causes watery diarrhea in newborn piglets and results in significant economic losses to the pig industry. Since first reported in Hong Kong in 2012, PDCoV has been subsequently detected in USA, South Korea, Thailand, and China's Mainland. Here we isolated a strain of PDCoV, named CHN-GD-2016,from the intestinal content of a diseased newborn piglet with severe diarrhea in a pig farm in Guangdong, China. PDCoV CHN-GD-2016 could be identified by immunofluorescence with PDCoV specific rabbit antisera, and typical crown-shaped particles with spiky surface projections of this PDCoV were observed with electron microscopy. Genomic analysis showed that the PDCoV CHN-GD-2016 was closely related to other Chinese PDCoV strains, with the highest sequence similarity with the strain CHN/Tianjin/2016. Importantly, inoculation of newborn piglets with 1×10~5 TCID_(50) of CHN-GD-2016 by oral feeding successfully reproduced clear clinical symptoms, including vomiting, dehydration, and severe diarrhea in piglets. In addition, the virus RNA in rectal swabs from 1 to 7 days post inoculation was detected, macroscopic and microscopic lesions in small intestine were observed, and viral antigen was also detected in the small intestines with immunohistochemical staining. Collectively, the data show in this study confirms that PDCoV is present in Guangdong,China and is highly pathogenic in newborn piglets. | Zhichao Xu Huiling Zhong Qingfeng Zhou Yunping Du Li Chen Yun Zhang Chunyi Xue Yongchang Cao | 2018 | Virologica Sinica2018，33，2： | 16 |
| 9 | Environmental changes during early-middle Holocene from the sediment record of the Chaohu Lake,Anhui Province显示文摘A typical lake sediment core is obtained from the Chaohu Lake in the lower reaches of the Yangtze River,Anhui Province,China.The timing scale is constrained by AMS 14 C dating method.Climate proxies such as pollen and grain size in the core are analyzed to reconstruct the environment changes at this site approximately between 9870 and 2170 cal.a BP.The results indicate that at the research area, the climate in the early-middle Holocene had evolved through 3 stages.From 9870 to 6040 cal.a BP, proxy records show a warm and dry climate with low water levels after the late-glacial period.During this stage,cool and dry events occurred at about 8910 and 6060-6030 cal.a BP.Then,between 6040 and 4860 cal.a BP,the climate was humid and vegetation was more flourishing in the Chaohu Lake Valley.The Holocene Optimum occurred at 5840-5500 cal.a BP in the Chaohu Lake,showing the best condition of water and heat.Elm Decline occurred at the period of 5380-4930 cal.a BP.Since 4860 cal.a BP,the climate was warm and dry through 2170 cal.a BP as shown in both pollen spectrum and grain-size histories.Two obvious dry events occurred in 3760 and 2170 cal.a BP,respectively.At 2170 cal.a BP,the water level of the Chaohu Lake reached the lowest as the lakebed possibly exposed. Such lake sediment observations are consistent with the historical records in this area. | XinYuan Wang GuangSheng Zhang Li Wu XiHui Zhang EnLou Zhang XiaYun Xiao QingFeng Jiang | 2008 | Chinese Science Bulletin2008，53，S1： | 15 |
| 10 | The effect of surface roughness on thermal-elasto-hydrodynamic model of contact mechanical seals显示文摘In this paper,the effect of surface roughness on sealing clearance,pressure distribution,friction torque and leakage is studied by the thermal-elasto-hydrodynamic mixed lubrication model.A convergent nominal clearance is formed by the pressure deformation and thermal deformation of the seal faces.This causes more serious wear in the inner side than that of the outer side of the contact area.Mass leakage increases with the growing of the surface roughness.The temperature and thermal deformation on the seal surface increases substantially if the roughness is reduced.The contact mechanical seals have consistent performance when the standard deviation of surface roughness is approximately 0.2μm.In order to validate the theoretical analysis model,a method combining the measurement of three-dimensioned profile and Raman spectrum is proposed. | WEN QingFeng LIU Ying HUANG WeiFeng SUO ShuangFu WANG YuMing | 2013 | Science China(Physics,Mechanics & Astronomy)2013，56，10： | 13 |
| 11 | Climatic and lake environmental changes in the Serling Co region of Tibet over a variety of timescales显示文摘The Serling Co region is located at the transitional zone of the interaction between the Indian monsoon and the westerlies over the Tibetan Plateau. The Serling Co lake covers a water area of2,389 km2(June 2017) in a 45,530 km2drainage basin. Under the dramatic hydro-meteorological changes on the Tibetan Plateau in recent decades, and complex hydrological compositions of rivers and lakes in the basin, the lake area expanded by 43%, from1,667 km2in 1976, to 2,389 km2in 2017 (1)In 2014 it surpassed Nam Co as the largest lake on the Tibetan Plateau [2], and exerts significant effect on regional environmental conditions. | Liping Zhu Junbo Wang Jianting Ju Ning Ma Yinsheng Zhang Chong Liu Boping Han Linshan Liu Mingda Wang Qingfeng Ma | 2019 | Science Bulletin2019，64，7： | 13 |
| 12 | Effect of sintering temperature in argon atmosphere on microstructure and properties of 3D printed alumina ceramic cores显示文摘Alumina ceramics with different sintering temperatures in argon atmosphere were obtained using stereolithography-based 3D printing.The effects of sintering temperature on microstructure and physical and mechanical properties were investigated.The results show that the average particle size,shrinkage,bulk density,crystallite size,flexural strength,Vickers hardness,and nanoindentation hardness increased with the increase in sintering temperature,whereas the open porosity decreased with increasing sintering temperature.No change was observed in phase composition,chemical bond,atomic ratio,and surface roughness.For the sintered samples,the shrinkage in Z direction is much greater than that in X or Y direction.The optimum sintering temperature in argon atmosphere is 1350℃with a shrinkage of 3.0%,3.2%,and 5.5%in X,Y,and Z directions,respectively,flexural strength of 26.7 MPa,Vickers hardness of 198.5 HV,nanoindentation hardness of 33.1 GPa,bulk density of 2.5 g/cm^3,and open porosity of 33.8%.The optimum sintering temperature was 70℃higher than that sintering in air atmosphere when achieved the similar properties. | He LI Yongsheng LIU Yansong LIU Qingfeng ZENG Kehui HU Zhigang LU Jingjing LIANG | 2020 | Journal of Advanced Ceramics2020，9，2： | 13 |
| 13 | Passive-source ocean bottom seismograph(OBS) array experiment in South China Sea and data quality analyses显示文摘Long-term passive source ocean bottom seismograph(OBS) observatory is challenging due to various technical difficulties. In order to gain experience in this field, and to reveal the lithospheric structure beneath the extinct ridge in the central South China Sea(SCS), we carried out a passive source OBS array experiment, which includes 18 OBSs, in the deep portion of SCS. Here we present the instrumentation, the OBS deployment and recovery of this experiment, and more importantly, the data quality evaluated by a number of approaches. Through processing and inspecting waveforms from global, regional and local earthquakes, we find that most of recovered OBSs have good data quality with discernible main phases. The ambient noise analyses of OBS recordings show that their noise is higher than the global average, and the horizontal component is noisier than the vertical, indicating current impacts on horizontal components are more severe. In the period range of 5–10 s, there is a noise notch for the SCS OBSs, and noise levels of horizontal components are comparable to the vertical. This feature, which is not seen at OBS stations in open ocean, suggests the distant sources for double frequency microseism in this marginal sea are not significant. In addition, we successfully determined the orientations for 7 OBSs by investigating their Rayleigh wave polarizations; and we demonstrated the dispersion feature of Rayleigh waves through the frequency-time analysis. Finally, we summarized lessons learned from this experiment regarding the passive source OBS investigations in SCS. | Chenguang Liu Qingfeng Hua Yanliang Pei Ting Yang Shaohong Xia Mei Xue Ba Manh Le Da Huo Fang Liu Haibo Huang | 2014 | Chinese Science Bulletin2014，59，33： | 11 |
| 14 | A group of SUVH methyl-DNA binding proteins regulate expression of the DNA demethylase ROS_1 in Arabidopsis显示文摘DNA methylation is typically regarded as a repressive epigenetic marker for gene expression.Genome-wide DNA methylation patterns in plants are dynamically regulated by the opposing activities of DNA methylation and demethylation reactions. In Arabidopsis, a DNA methylation monitoring sequence(MEMS) in the promoter of the DNA demethylase gene ROS_1 functions as a methylstat that senses these opposing activities and regulates genome DNA methylation levels by adjusting ROS_1 expression. How DNA methylation in the MEMS region promotes ROS_1 expression is not known. Here, we show that several Su(var)3-9 homologs(SUVHs) can sense DNA methylation levels at the MEMS region and function redundantly to promote ROS_1 expression. The SUVHs bind to the MEMS region, and the extent of binding is correlated with the methylation level of the MEMS.Mutations in the SUVHs lead to decreased ROS_1 expression, causing DNA hypermethylation at more than 1,000 genomic regions. Thus, the SUVHs function to mediate the activation of gene transcription by DNA methylation. | Xinlong Xiao Jieqiong Zhang Tao Li Xing Fu Viswanathan Satheesh Qingfeng Niu Zhaobo Lang Jian-Kang Zhu Mingguang Lei | 2019 | Journal of Integrative Plant Biology2019，61，2： | 11 |
| 15 | Application of customized augments fabricated by rapid prototyping for severe bone defects of the knee显示文摘With the population aging and an increasing desire for a high quality of life,millions of patients who suffered knee arthropathy have undergone total knee arthroplasty (TKA).Although the success rate for primary TKA has been quite high,the number of revision surgeries can not be ignored.Bone loss is one of the challenges confronting surgeons who perform revision TKAs as it can impair alignment accuracy and the long-term stability of the implant.Although several options are available for bone loss after TKA--cement,bone grafting,standard augments,and hinged implants--there is no single ideal option available for all patients with a severe bone defect because of the variety and severity of the defects.1 The burgeoning rapid prototyping (RP) technique,which has been used to fabricate components with complex and unique structures,may offer a novel option in these cases. | Yin Qingfeng Liu Wenguang Wang Shaojin | 2014 | Chinese Medical Journal2014，，15： | 10 |
| 16 | Catalytic Reduction of CO2 to CO via Reverse Water Gas Shift Reaction:Recent Advances in the Design of Active and Selective Supported Metal Catalysts显示文摘The catalytic conversion of CO2 to CO via a reverse water gas shift(RWGS)reaction followed by well-established synthesis gas conversion technologies may provide a potential approach to convert CO2 to valuable chemicals and fuels.However,this reaction is mildly endothermic and competed by a strongly exothermic CO2 methanation reaction at low temperatures.Therefore,the improvement in the low-temperature activities and selectivity of the RWGS reaction is a key challenge for catalyst designs.We reviewed recent advances in the design strategies of supported metal catalysts for enhancing the activity of CO2 conversion and its selectivity to CO.These strategies include varying support,tuning metal–support interactions,adding reducible transition metal oxide promoters,forming bimetallic alloys,adding alkali metals,and enveloping metal particles.These advances suggest that enhancing CO2 adsorption and facilitating CO desorption are key factors to enhance CO2 conversion and CO selectivity.This short review may provide insights into future RWGS catalyst designs and optimization. | Min Zhu Qingfeng Ge Xinli Zhu | 2020 | Transactions of Tianjin University2020，26，3： | 9 |
| 17 | Dry/wet climate zoning and delimitation of arid areas of Northwest China based on a data-driven fashion显示文摘The division of arid areas is important in water and land resources management, planning and for a long-term agricultural, economic and social planning. Northwest China(NW) dominates the main arid areas in China. There is thus a need to adopt adequate concepts relative to the scope of arid areas of NW China and identify its climate types and characteristics. In this study, we analyzed climatic data over the last 30 years(1981–2010) from 191 stations in three provinces and three autonomous regions of NW China. The factor-cluster analysis tech- nique(FC), an objective and automated method was employed to classify the dry/wet climate zones. The traditional methods with predefined thresholds were adopted for providing a comparison with FC. The results showed that the wet/dry climate zones by FC were mainly distributed along mountains, rivers and desert borders. Climate-division boundaries relied heavily on the major terrain features surrounding the grouped stations. It also showed that the climate was dry in the plain sandy areas but relatively wet in the high mountain areas. FC method can reflect the climate characteristics more fully in NW China with varied and complicated topography, and outperform the tradi- tional climate classifications. Arid areas of NW China were defined as four climate types, including five resultant classes in FC classifications. The Qinling and Da Hinggan Mountains were two important boundaries, besides main administrative boundaries. The results also indicated that there are some differences between two traditional clas- sifications. The precipitation moved and fluctuated to an extent, which confirmed that climate change played an important role in the dry/wet climate zoning, and the boundaries of dry/wet climate zones might change and migrate with time. This paper is expected to provide a more in-depth understanding on the climate characteristics in arid areas of NW China, and then contribute to formulate reasonable water and land management planning and agri- cultural production programs. | QingLing GENG PuTe WU QingFeng ZHANG XiNing ZHAO YuBao WANG | 2014 | Journal of Arid Land2014，6，3： | 9 |
| 18 | Palaeoecological and palaeoenvironmental significance of someimportant spores and micro-algae in Quaternary deposits显示文摘Spores of ferns and allied plants, and micro-algae frequently occur in abundance in Quaternary deposits, but their palaeoenvironmental significance is seldom evaluated. This paper presents morphological descriptions of spores of Selaginella sinensis (Desv.) Spring, 1843 (Selaginellaceae) and Ceratopteris cf. thalictroides (L.) Brongniart, 1821 (Parkeriaceae) and the algae Pediastrum boryanum (Turpin) Meneghini, 1840, P. simplex Meyen, 1829, P. integrum N geli, 1849 (all Hydrodictyaceae), Spiniferites Mantell, 1850, emend. Sarjeant, 1970 (Spiniferitaceae) and Concentricystes Rossignal, 1962, emend. Jiabo, 1978 (systematic position unclear), and discusses their occurrence in mostly Quaternary sedimentary successions. All are closely associated with aquatic habitats. Extant Selaginella sinensis often colonizes fairly wet hillsides and gaps between rocks, and shady sides of ravines and slopes; it is also found within thickets of trees and shrubs (boscages) and in forests with calcareous soils. Ceratopteris thalictroides, Pediastrum and Concentricystes inhabit freshwater lakes and both natural and artificial wetlands, such as paddy fields and ditches. Spiniferites is a salt-water genus and usually associated with the marine realm. Fossil and subfossil representatives of all of these taxa can be useful proxies of biodiversity and, therefore, also important for determining environmental conditions during the Quaternary period. | TANG LingYu MAO LiMi Lü XinMiao MA QingFeng ZHOU ZhongZe YANG ChunLei KONG ZhaoChen BATTEN David J | 2013 | Chinese Science Bulletin2013，58，25： | 9 |
| 19 | First-principles study of structure,mechanical and optical properties of La-and Sc-doped Y2O3显示文摘The electronic,mechanical and optical properties of La-and Sc-doped Y2O3 were investigated using firstprinciples calculations.Two doping sites of Sc and La in Y2O3 were modeled.The calculated values of the energy of formation show that the most energetically favorable site for a La atom in Y2O3 is a d-site Y atom,while for Sc a b-site Y atom is the more stable position.The calculated band gap shows a slight decrease with increasing La or Sc concentration.The calculated results for the mechanical and optical properties of Y(2-x)RxO3(R=Sc or La,0 | Xian Zhang Sen Gao Wenhua Gui Qingfeng Zeng | 2019 | Journal of Rare Earths2019，37，8： | 8 |
| 20 | An experimental and numerical study on the charring rate of timber beams exposed to three-side fire显示文摘To investigate the charring rate of timber beams exposed to three-side fire, a total of fifteen new and used Douglas-Fir timber beams in four groups exposed to three-side fire were experimentally studied, together with the finite element analyses of the temperature distribution in the beam section. The durations of fire exposure were 0 (on a test piece), 10, 15, 20 and 30 min, according to the ISO 834 standard fire curve. The charring depth of each timber beam was calculated by averaging the values at one-third and two-thirds along each cross section to give the charring rate of timber beams. It was found that the timber beam's charring rate reduces as the duration of fire exposure increases and the vertical charring rate is slightly higher than the horizontal one. The areas of beam sections reduce due to charring and the strength and stiffness of the pyrolysis layer near the charring edge decrease owing to the high-temperature. The average horizontal and vertical charring rates are 0.98 and 1.08 mm/min, respectively. To take into account the difference between the test furnace temperature curve and the ISO 834 stand- ard fire curve, some corrections were made for these data to yield the solution for charring rate. With the help of the finite element software ANSYS, the temperature distribution of the wood's cross-section was analyzed. The longer the exposure time is, the greater the effect of density will impose on the distribution of temperature, but the moisture content has no effect. | ZHANG Jin LIU ZengHui XU YiXiang MA ShuWei XU QingFeng | 2012 | Science China(Technological Sciences)2012，55，12： | 8 |
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