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| 1 | Paleoclimatic significance of grain size of loess-palaeosol deposit in Chinese Loess Plateau显示文摘Particle size analysis for samples from three last glacial cycle loess_palaeosol profiles along a northwest_southeast transection on the Chinese Loess Plateau has been carried out. The paleoclimatic significance of grain size indices has been obtained by analyzing the fraction content variations and their comparisons with global ice volume and solar radiation variations. The results show that (i) paleoclimatic significance of the grain size indices of loess_palaeosol deposit is different with grain size fraction content and sampling points in Chinese Loess Plateau; (ii) the sub_coarse grain fraction is a good proxy index of East Asia winter monsoon strength and therefore can be used to detect the global climate changes; (iii) the content of sub_fine and fine grain fractions is influenced by both the input of sub_coarse grain fraction and pedogenesis; (iv) the sub_coarse fraction exhibits a negative relationship with the sub_fine and fine fraction. | 鹿化煜 安芷生 | 1998 | Science China Earth Sciences1998，41，6： | 47 |
| 2 | A sedimentological proxy indicator linking changes in loess and deserts in the Quaternary显示文摘From Yulin, which is located in the transitional zone between the Loess Plateau and the Mu Us desert, to Weinan in the southernmost part of the Loess Plateau, 9 loess sections were studied. Grain size analyses show that the advance-retreat changes of the deserts in northern China may be the most important factor controlling changes in the sand particle percentage of the loess-soil sequences during the last glacial-interglacial period. It is thus suggested to use the sand grain content of loess deposits as a proxy indicator of desert variations. Applying this indicator to the last glacial loess deposits in the northwestern part of the Loess Plateau reveals that there were many millennial-scale cycles of the desert environments. | 丁仲礼 孙继敏 刘东生 | 1999 | Science China Earth Sciences1999，42，2： | 24 |
| 3 | Pretreated methods on loess-palaeosol samples granulometry显示文摘Twenty representative samples were collected from the Chinese loess plateau and each sample was prepared in 6 different ways respectively in order to test the influences of pretreated methods on grain size measurement. The results show that (ⅰ) different pretreated methods can make a big difference for the samples granulometry; (ⅱ) soaking in distilled water for one day, and then treating with an ultrasonic machine for 10 min can make the sample dispersed. | Huayu Lu Zhisheng An | 1998 | Chinese Science Bulletin1998，43，3： | 20 |
| 4 | Trend analysis of sediment grain size and sedimentary process in the central South Yellow Sea显示文摘With the method of trend analysis of sediment grain size, the sediment transport trend of the fine-grained sediments area in the central South Yellow Sea was studied. The results demonstrated that there is a sedimentation center around the point of 123.4° E, 35.1°N, and the sediments outside the center are transported to it. The patterns of sediment transportation and deposition in the Yellow Sea should be controlled by cyclonic circulation (including the Yellow Sea Cold Water Mass) and cold water gyre. The study also showed that the method of trend analysis of sediment grain size has prospective utilization in the fine-grained sediment deposited area on large-scale continental shelf. | SHI Xuefa CHEN Chunfeng LIU Yanguang REN Hong WANG Huiyan | 2002 | Chinese Science Bulletin2002，47，14： | 17 |
| 5 | Characteristics of paleoflood deposits archived in unit T0403 of Yuxi Site in the Three Gorges reservoir areas,China显示文摘Based on the detailed analyses,multi-proxies such as AMS 14 C dating,grain size,component and morphology of heavy minerals,micromorphology of zircon,magnetic susceptibility,Rb/Sr and Hg content are used to research the paleoflood sediments archived in the Yuxi Site.The research indicates that, since 7.6 kaBP,at least 16 times of paleoflood with water level above Wusong Elevation 147.024 m(a.s.l.) left deposits in the Neolithic layers of unit T0403 from the Yuxi Site.The results are induced from the following aspects:(1)The plaeoflood sediments take on great similarities with modern flood sediments in the Yuxi Site and Zhongba Site in probability cumulative curves which mainly show a pattern of 3 segments in fluvial pattern.(2)There is some resemblance between the heavy mineral components and the zircon shape characteristics of paleoflood deposits and those of modern flood deposits.(3) Magnetic susceptibility values(40.44―70.10SI)are lower than those of sediments from cultural layers (59.59―188.68SI).(4)Hg values(290.71―742.51 ng/g)are lower than those of sediments from cultural layers(344.16―10518.17 ng/g).(5)Rb/Sr values are higher than those of sediments from cultural layers, while those of the 4th,5th,6th,7th,8th cultural layers are high,which shows that they are inundated by paleoflood.The reason for many flood deposits existing is related to the site situated on the first terrace where the Yuxi River joins with the Yangtze River.As there are some similarities between the plaeoflood sediments and those of the Zhongba Site,it is feasible to confirm the existence of paleoflood sediments based on the above points. | ZHU Cheng MA ChunMei XU WeiFeng BAI JiuJiang ZHENG ChaoGui ZHU GuangYao WANG HuiLin CHEN Ye LU XueFeng | 2008 | Chinese Science Bulletin2008，53，S1： | 16 |
| 6 | Grain size-dependent Mg/Si ratio effect on the microstructure and mechanical/electrical properties of Al-Mg-Si-Sc alloys显示文摘Al-Mg-Si-Sc alloys with different Mg/Si ratio(<1.73 in wt.% vs>1.73 in wt.%) and different grain size(coarse grains vs ultrafine grains) were prepared, which allowed to investigate the grain size-dependent Mg/Si ratio effect on the microstructural evolution and concomitantly on the hardness and electrical conductivity when subjected to aging at 200℃. In the coarse-grained Al-Mg-Sc-Sc alloys, the β' precipitation within the grain interior and also the precipitation hardening were highly dependent on the Mg/Si ratio,while the electrical conductivity was slightly affected by the Mg/Si ratio. A promoted β' precipitation was found in the case of Si excess(Mg/Si ratio <1.73), much greater than in the case of Mg excess(Mg/Si ratio>1.73). While in the ultrafine-grained Al-Mg-Si-Sc alloys, the electrical conductivity rather than the hardness was more sensitive to the Mg/Si ratio. The alloy with Si excess displayed electrical conductivity much higher than its counterpart with Mg excess. This is rationalized by the grain boundary precipitation promoted by Si, which reduced the solute atoms and precipitates within the grain interior. Age softening was found in the ultrafine-grained alloy with Si excess, but the ultrafine-grained alloy with Mg excess held the hardness almost unchanged during the aging. The hardness-conductivity correlation is comprehensively discussed by considering the coupling effect of Mg/Si ratio and grain size. A strategy to simultaneously increase the hardness/strength and electrical conductivity is proposed for the Al-Mg-SiSc alloys, based on present understanding of the predominant factors on strengthening and conductivity,respectively. | Shengyu Jiang Ruihong Wang | 2019 | Journal of Materials Science & Technology2019，35，7： | 13 |
| 7 | Effect of hydrophilic silica nanoparticles on hydrate formation: Insight from the experimental study显示文摘Invasion of drilling fluid into natural gas hydrate deposits during drilling might damage the reservoir,induce hydrate dissociation and then cause wellbore instability and distortion of the data from well logging. Adding nanoparticles into drilling fluid is an effective method in reducing the invasion of drilling fluid and enhancing borehole stability. However, the addition of nanoparticles might also introduce hydrate formation risk in borehole because they can act as the 'seeds' for hydrate nucleation. This paper presents an experimental study of the effect of hydrophilic silica nanoparticle on gas hydrate formation in a dynamic methane/liquid-water system. In the experiment, the ultrapure water with and without1.0 wt%–6.0 wt% concentrations of silica nanoparticles, grain sizes of 20 and 50 nm, were pressurized by methane gas under varied conditions of temperature and pressure. The induction time, the gas consumption, and the average rate of gas consumption in the system were measured and compared to those in ultrapure water. The results show that a concentration of 4.0 wt% hydrophilic SiO_2 particles with a grain size of 50 nm has a relatively strong inhibition effect on hydrate formation when the initial experimental condition is 5.0 °C and 5.0 MPa. Compared to ultrapure water, the hydrophilic nano-SiO_2 fluid increases the induction time for hydrate formation by 194% and decreases the amount and average rate of hydrate formation by 10% and 17%, respectively. This inhibition effect may be attributed to the hydrophilicity,amount and aggregation of silica nanoparticle according to the results of water activity and zeta potential measurements. Our work also elucidates hydrophilic, instead of hydrophobic, nanoparticles can be added to the drilling fluid to maintain wellbore stability and to protect the hydrate reservoir from drilling mud damage, because they exhibit certain degree of hydrate inhibition which can reduce the risk of hydrate reformation and aggregation during gas hydrate or deep water drilling if their concentration can be controlled properly. | Ren Wang Tianle Liu Fulong Ning Wenjia Ou Ling Zhang Zhen Wang Li Peng Jiaxin Sun Zhichao Liu Tianshu Li Huicui Sun Guosheng Jiang | 2019 | Journal of Energy Chemistry2019，28，3： | 12 |
| 8 | Geochemical indicator of original eolian grain size and implications on winter monsoon evolution显示文摘Grain size of eolian deposits from the Loess Plateau in China has been widely used to reconstruct the history of the East Asian winter monsoon. However, the grain size of bulk samples is only partially indicative to the strength of the winter monsoon because post-depositional weathering processes have significantly changed the grain size of original eolian particles. Here, non-weathered loess samples were separated into eight different particle fractions, and major chemical elements were determined in order to establish a geochemical indicator of original eolian grain size. The results show that SiO2and AI2O3contents and the SiO2/AI203 ratio in different fractions vary regularly with grain size, and that a good linear relation exists between the SiO2/AI2O3 ratio and grain size for the fractions<50μm. Because Al and Si are among the most stable elements and pedogenic processes in the Loess Plateau cannot affect the SiO2/AI2O3 ratio, this index can be used to reflect the grain size of original eolian | 彭淑贞 郭正堂 | 2001 | Science China Earth Sciences2001，44，S1： | 11 |
| 9 | Effect of suspended sediment grain size on channel sedimentation in the lower Yellow River and some implications显示文摘Based on the data of suspended sediment transport and channel sedimentation in various grain size fractions in the period of 1962―1985, the relationship between channel sedimentation in the lower Yellow River and sediment input has been plotted with respect to each grain size fraction. Several fill-scour thresholds in sediment input have been identified from these graphs. It was found that the fill-scour threshold in sediment input decreases with the increase in fraction grain size. The correlation coefficient between channel sedimentation and sediment input becomes larger with the increasing fraction grain size, indicating that channel sedimentation depends more on coarser grain size fractions than on smaller ones. The fraction channel sedimentation induced by unit change of fraction sediment input increases with grain size. Of the input of sediment larger than 0.025 mm, 43.73% was deposited on the channel, and for inputs of sediments larger than 0.05 mm and larger than 0.10 mm, 76.61% and 97.68% were deposited on the channel, respectively. Thus, for reduction of each ton of sediment larger than 0.10 mm from the drainage basin, the resultant reduction in channel sedimentation in the lower Yellow River would be 1.275 times that for the sediment larger than 0.10 mm, and 2.234 times that for the sediment larger than 0.025 mm. Therefore, if the erosion and sediment control measures are enforced in the areas where >0.05 or >0.10 mm sediment is produced, then the best beneficial will be achieved in reducing sedimentation in the lower Yellow River. | XU JiongXin HU ChunHong CHEN JianGuo | 2009 | Science China(Technological Sciences)2009，52，8： | 9 |
| 10 | Influence of grain size on the small fatigue crack initiation and propagation behaviors of a nickel-based superalloy at 650℃显示文摘GH4169 at 650℃ in atmosphere was investigated by using single edge notch tensile specimens. The number of main cracks and crack initiation mechanisms at the notch surface strongly depended on the grain size. The crack initiation life accounted for more percentages of the total fatigue life for the alloy with smaller grain size. The fatigue life generally increased with increasing crack initiation life. The small crack transited to long crack when its length reached 10 times the grain size. | Xumin Zhu Congyang Gong Yun-Fei Jia Runzi Wang Chengcheng Zhang Yao Fu Shan-Tung Tu Xian-Cheng Zhang | 2019 | Journal of Materials Science & Technology2019，35，8： | 9 |
| 11 | Spatial heterogeneity for grain size distribution of eolian sand soil on longitudinal dunes in the southern Gurbantunggut Desert显示文摘The grain size composition, distribution characteristics and spatial variation of eolian sand soil on distinct positions across two longitudinal dunes and interdune areas were studied by means of conventional grain size analysis and geostatistical methods. In the study, 184 samples of eolian sand soil from the 0-30cm layer were systemically collected and measured from two longitudinal dunes and interdunes in the southern Gurbantunggut Desert. The results show that the dominant grain sizes are fine and very fine sands, and the differences of grain size compositions between the distinct geomorphologic positions are significant. The contents of clay and silt are highest on the interdune areas and lowest on the crests, and higher on the leeward slopes than on the windward slopes. The contents of very fine and fine sands are highest on the windward slopes and lowest on the crests. The contents of medium, coarse and very coarse sands are lowest on the interdune lands, and highest on the crests, and are identical on the two slopes. The coarser sizes (φ1) and mean sizes (Mz) for eolian sand soil all have a varying tendency from fine to coarse sizes with interdune area → leeward slope → windward slope → crest, and the sorting (σ) are poorly to well sorted. The results of geostatistical analysis reveal that φ1, Mz and σ values are moderately to strongly spatially autocorrelated. The values of the spatially correlated ranges are φ1<σ | Qian, YiBing Wu, ZhaoNing Yang, HaiFeng Jiang, Chao | 2009 | Journal of Arid Land2009，1，1： | 9 |
| 12 | Grain size distribution of quartz isolated from Chinese loess/ paleosol显示文摘Grain size distribution of bulk loess-paleosol and quartz chemically extracted from the loess/paleosol shows that mean size of the bulk samples is always finer than that of the quartz. The original aeolian depositions have been modified to various degrees by post-depositional weathering and pedogenic processes. The grain size distribution of the isolated quartz should be close to that of the primary aeolian sediment because the chemical pretreatment excludes secondary produced minerals. Therefore, the grain size of the quartz may be considered to more clearly reflect the variations of winter monsoon intensity. | SUN Youbin LU Huayu AN Zhisheng | 2000 | Chinese Science Bulletin2000，45，24： | 9 |
| 13 | Fatigue behavior of CoCrFeMnNi high-entropy alloy under fully reversed cyclic deformation显示文摘Bulk ultrafine-grained(UFG) CoCrFeMnNi high-entropy alloy(HEA) with fully recrystallized microstructure was processed by cold rolling and annealing treatment. The high-cycle fatigue behaviors of the UFG HEA and a coarse-grained(CG) counterpart were investigated under fully reversed cyclic deformation.The fatigue strength of the UFG HEA can be significantly enhanced by refining the grain size. However,no grain coarsening was observed in the UFG HEA during fatigue tests. Mechanisms for the superior mechanical properties of the UFG HEA were explored. | Y.Z.Tian S.J.Sun H.R.Lin Z.F.Zhang | 2019 | Journal of Materials Science & Technology2019，35，3： | 8 |
| 14 | A novel unified model predicting flow stress and grain size evolutions during hot working of non-uniform as-cast 42CrMo billets显示文摘The cast preformed forming process(CPFP) is increasingly considered and applied in the metal forming industries due to its short process, low cost, and environmental friendliness, especially in the aerospace field. However, how to establish a unified model of a non-uniform as-cast billet depicting the flow stress and microstructure evolution behaviors during hot working is the key to microstructure prediction and parameter optimization of the CPFP. In this work, hot compression tests are performed using a non-uniform as-cast 42 CrMo billet at 1123–1423 K and 0.01–1sà1. The effect laws of the non-uniform state of the as-cast billet with different initial grain sizes on the flow stress and microstructure are revealed deeply. Based on experimental results, a unified model of flow stress and grain size evolutions is developed by the internal variable modeling method. Verified results show that the model can well describe the responses of the flow stress and microstructure to deformation conditions and initial grain sizes. To further evaluate its reliability, the unified model is applied to FE simulation of the cast preformed ring rolling process.The predictions of the rolling force and grain size indicate that it could well describe the flow stress and microstructure evolutions during the process. | Lianggang GUO Fengqi WANG Pengliang ZHEN Xuechao LI Mei ZHAN | 2019 | Chinese Journal of Aeronautics2019，32，2： | 8 |
| 15 | GRAIN LENGTH AND AWN 1 negatively regulates grain size in rice显示文摘Grain size is an important factor determining yield in rice. Here, we identified a recessive mutant gene, grain length and awn 1 (gla1), which caused a significant increase in grain length and weight, and was associated with long awns. The gla1 mutation was mapped to a single-nucleotide polymorphism in a gene encoding a cytoplasmically-localized mitogen-activated protein kinase (MAPK) phosphatase. Overexpression of GLA1 caused a decrease in grain length, and the GLA1 protein interacted with OsMAPK6. These results suggest that GLA1 may serve as a negative regulator of the OsMAPKK4-OsMAPK6 cascade, controlling grain size via the dephosphorylation of OsMAPK6. | Tao Wang Ting Zou Zhiyuan He Guoqiang Yuan Tao Luo Jun Zhu Yueyang Liang Qiming Deng Shiquan Wang Aiping Zheng Huainian Liu Lingxia Wang Ping Li Shuangcheng Li | 2019 | Journal of Integrative Plant Biology2019，61，10： | 7 |
| 16 | DUCTILEBRITTLETRANSITION OF POLYCRYSTALLINE Ni_3Al WITH VARYING GRAIN SIZE显示文摘It is known that in B (un)doped Ni 3Al polycrystals, the dependence of yield strength on grain size follows the Hall Petch relationship: σ y= σ 0+ K y d -1/2 , and the slope K y can be reduced by B doping owing to the lowering of grain boundary resistance to slip transmission. If the intergranular cracking in polycrystalline Ni 3Al occurs from the microcavity along the grain boundaries, the effective external tensile stress for the propagation of the crack like microcavity along the grain boundaries can be deduced as: σ f= σ i+ K u d -1/2 , where K u reflects the effects of such factors as environment, strain rate, boron doping and the orientation of the grain boundary on the trend of intergranular cracking. For loaded polycrystalline Ni 3Al, it should be competitive between the intergranular cracking and slip transmission across the grain boundary. Therefore, comparing the varieties of both σ y and σ f with grain size, the dependence of ductile brittle transition on grain size, and the effects of the above factors on ductile brittle transition can be expected. The model also predicts that there exists a critical grain size for the ductile brittle transition of polycrystalline Ni 3Al alloys, and B doping can increase the critical grain size due to the reduction of the slope K y and the increase of K u. The reported experimental results verified the above model. | G. W. Han, D. Feng and C. S. Lee Central Iron & Steel Research Institute, Beijing 100081, China Dept. Physical & Mater. Sci., City University of Hong Kong Hong Kong, China | 1999 | 中国有色金属学会会刊:英文版1999，9，S1： | 7 |
| 17 | Effects of the grain size distribution on the temperature-dependent magnetic susceptibility of magnetite nanoparticles显示文摘Magnetite is an important magnetic remanence carrier in natural samples and therefore is of great interest in paleo-, rock-, and environmental magnetism. The magnetic properties of magnetite depend on many factors, e.g., concentration and grain size distribution (GSD). In this study, we theoretically investigated the temperature-dependent susceptibility (TDS) of magnetite nanoparticles with a lognormal GSD. Results show that the TDS is affected highly by the GSD mainly in three aspects. Firstly, the unblocking process becomes smoother with the increase of distribution width, characterizing as a wider Hopkinson peak on the TDS curve. Secondly, the blocking temperature increases with the increase of the median diameter or/and the distribution width. Thirdly, the maximum susceptibility decreases with the increase of distribution width, and has a logarithmic function relation with the standard deviation of the distribution. As a case study, this model was further applied to the thermal products of the Chinese loess/paleosol samples to determine the granulometry of newly-formed magnetite upon heating based on TDS curves. The results demonstrate the fidelity and feasibility of this method to determine the GSD of nano-sized magnetic particles. | ZHAO XiangYu1,2 & LIU QingSong1 1 Paleomagnetism and Geochronology Laboratory (SKL-LE), Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China 2 Graduate University of Chinese Academy of Sciences, Beijing 100049, China | 2010 | Science China Earth Sciences2010，53，7： | 7 |
| 18 | Grain Size and Photocatalytic Activity of Nanometer TiO_2 Thin Films Prepared by the Sol-gel Method显示文摘Transparent anatase TiO2 nanometer thin films with photocatalytic activity were prepared via the sol-gel method on soda-lime glass. The thickness , crystalline phase, grain size, surface hydroxyl amount and so on were characterized by scanning electron microscopy (SEM) , X-ray diffraction (XRD), transmission electron microscopy ( TEM), X-ray photoelectron spectroscopy (XPS) and UV-visible spectrophotometer ( UV-VIS). The photocatalytic activity of TiO2 thin films was evaluated for the photocatalytic decolorization of aqueous methyl orange . The effects of film thickness on the crystalline phase, grain size, transmittance and photocatalytic activity of nanometer Ti02 thin films were discussed. | 余家国 | 2001 | Journal of Wuhan University of Technology(Materials Science)2001，16，2： | 7 |
| 19 | Big Grain3, encoding a purine permease, regulates grain size via modulating cytokinin transport in rice显示文摘Grain size is an important agronomic trait affecting grain yield,but the underlying molecular mechanisms remain to be elucidated.Here,we isolated a dominant mutant,big grainy(bg3-D),which exhibits a remarkable increase of grain size caused by activation of the PURINE PERMEASE gene,OsPUP4.BC3/OSPUP4 is predominantly expressed in vascular tissues and is specifically suppressed by exogenous cytokinin application.Hormone profiling revealed that the distribution of different cytokinin forms,in roots and shoots of the bg3-D mutant,is altered.Quantitative reverse transcription-PCR(qRT-PCR)analysis indicated that expression of rice cytokinin type-A RESPONSE REGULATOR(OsRR)genes is enhanced in the roots of the bgj-D mutant.These results suggest that OSPUP4 might contribute to the long-distance transport of cytokinin,by reinforcing cytokinin loading into vascular bundle cells.Furthermore,plants overexpressing OsPUP7,the closest homolog of OsPUP4,also exhibited a similar phenotype to the bg3-D mutant.Interestingly,subcellular localization demonstrated that OSPUP4 was localized on the plasma membrane,whereas OSPUP7 was localized to the endoplasmic reticulum.Based on these findings,we propose that OSPUP4 and OSPUP7 function in a linear pathway to direct cytokinin cell-to-cell transport,affecting both its long-distance movement and local allocation. | Yunhua Xiao Dapu Liu Guoxia Zhang Shaopei Gao Linchuan Liu Fan Xu Ronghui Che Yiqin Wang Hongning Tong Chengcai Chu | 2019 | Journal of Integrative Plant Biology2019，61，5： | 7 |
| 20 | Dynamic recrystallization behavior of 35CrMo structural steel显示文摘The dynamic recrystallization behavior of 35CrMo steel was studied with compression test in the temperature range of 1 223 1 423 K and the strain rate range of 0.01 10.00 s -1 . The initiation and evolution of dynamic recrystallization were investigated with microstructure analysis and then the critical strain ε c for dynamic recrystallization initiation, the strain for maximum softening rate ε * and the steady strain ε s were obtained to be 2.92×10 -3 Z 0.1381 , 1.60×10 -3 Z 0.178 0 and 3.26×10 -2 × Z 0.097 2 respectively by analysis of work hardening rate strain θ ε curves, where Z is the Zener Hollomon parameter. The dynamic recrystallization fraction was determined using recrystallization theory, and the effects of initial grain size, strain rate and deformated temperature on the dynamic recrystallization kinetics were investigated. The results show: X DRX =1- exp(-3.23( ε-ε cε s-ε c ) 2.28 ), the dynamic recrystallization fraction is slightly delayed due to the somewhat larger initial grain size and markedly delayed with the decrease of temperature. On the other hand, it is significantly accelerated with the increase of the strain rate. Finally, the relationships between the initiation time, ending time of dynamic recrystallization and the deformed temperature were analyzed in detail. | 张斌 张鸿冰 阮雪榆 | 2003 | Journal of Central South University of Technology2003，10，1： | 6 |
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