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| 1 | The age of the base of the Paleoproterozoic Hutuo Group in the Wutai Mountains area, North China Craton: SHRIMP zircon U-Pb dating of basaltic andesite显示文摘Basalt and basaltic andesite metamorphosed at greenschist facies occurs with conglomerate layers at the bottom of the Paleoproterozoic Hutuo Group in the Wutai Mountains area, North China Craton. Detailed geological surveying confirms that these volcanic rocks are conformable within the neighboring sedimentary rocks. The SHRIMP results on basaltic andesite are divided into two groups. In one group the 207Pb/206Pb ages are from 2433 to 2558 Ma, which is consistent with the basement crustal age in Fuping and Wutai areas. In the other group, 13 grains yielded a weighted mean 207Pb/206Pb age of 2140±14 Ma. The latter is interpreted as the eruption age of the basaltic andesite, and gives the age of the base of the Hutuo Group. This result further suggests that the Hutuo Group formed in the middle Paleoproterozoic, not the early Palaeoproterozoic or late Archaean, as thought before, and is related to a 2.2-2.1 Ga rifting event in the Central North China Craton. | DU LiLin YANG ChongHui GUO JingHui WANG Wei REN LiuDong WAN YuSheng GENG YuanSheng | 2010 | Chinese Science Bulletin2010，55，17： | 43 |
| 2 | Changes in biodiversity and ecosystem function during the restoration of a tropical forest in south china显示文摘Tropical forests continue to vanish rapidly,but few long-term studies have ever examined if and how the lost forests can be restored.Based on a 45-year restoration study in south China,we found that a tropical rain forest,once completely destroyed,could not recover naturally without deliberate restoration efforts.We identified two kinds of thresholds that must be overcome with human ameliorative measures before the ecosystem was able to recover.The first threshold was imposed primarily by extreme physical conditions such as exceedingly high surface temperature and impoverished soil,while the second was characterized by a critical level of biodiversity and a landscape context that accommodates dispersal and colonization processes.Our three treatment catchments(un-restored barren land,single-species plantation,and mixed-forest stand)exhibited dramatically different changes in biodiversity and ecosystem functioning over 4 decades.The mixed forest,having the highest level of biodiversity and ecosystem functioning,possesses several major properties of tropical rain forest.These findings may have important implications for the restoration of many severely degraded or lost tropical forest ecosystems. | REN Hai,LI ZhiAn,SHEN WeiJun,YU ZuoYue,PENG ShaoLin,LIAO ChongHui,DING MingMao & WU JianGuo 1 South China Botanical Garden,Chinese Academy of Sciences,Guangzhou 510650,China 2 Institute of Ecology and Evolution,Zhongshan University,Guangzhou 510275,China 3 Guangdong Institute of Entomology,Guangzhou 510275,China 4 School of Life Sciences and Global Institute of Sustainability,Arizona State University,Tempe,AZ 85287,USA | 2007 | Science China(Life Sciences)2007，50，2： | 9 |
| 3 | Provenance of the Paleoproterozoic Hutuo Group basal conglomerates and Neoarchean crustal growth in the Wutai Mountains,North China Craton:Evidence from granite and quartzite pebble zircon U-Pb ages and Hf isotopes显示文摘Zircon U-Pb ages(SHRIMP and LA-ICPMS) and Lu-Hf isotope data(LA-ICPMS) are presented for two granite and two quartzite pebbles from the basal conglomerates of the Sijizhuang Formation in the Hutuo Group from the Wutai Mountains area in the North China Craton.These two granite pebbles give zircon 207 Pb/206 Pb ages of 2513±8 Ma and 2527±8 Ma respectively,which are consistent with the emplacement ages of the Wangjiahui grey granite and Guangmingsi or Shifo granite in the Wutai Mountains.Detrital zircons from those two quartzite pebbles are mostly 2550-2490 Ma old with lesser number of 2800-2550 Ma grains,which is similar to the ages of detrital zircons from quartzites in the Gaofan Subgroup of the Neoarchean Wutai Group.Thus,the pebbles in the Hutuo Group basal conglomerates were derived locally from Wutai Mountains Neoarchean sources.Zircons from the Sijizhuang Formation conglomerate granite and quartzite pebbles mostly have positive ε Hf(t) values,a minority with ε Hf(t) values like model depleted mantle(DM) of the same age,but with most showing DM model ages 200-100 Ma.This indicates that most of the source materials were derived from the mantle within the previous 200 million years,whereas some are derived from 2550-2510 Ma juvenile crustal additions.This additional evidence suggests that in the North China Craton there was important initial polycyclic crustal formation and cratonization in the late Neoarchaean,prior to superimposed Palaeoproterozoic orogenic cycles. | DU LiLin YANG ChongHui WANG Wei REN LiuDong WAN YuSheng SONG HuiXia GAO LinZhi GENG YuanSheng HOU KeJun | 2012 | Science China Earth Sciences2012，55，11： | 8 |
| 4 | Petrological Implication of the Albite Rims in the Felsic Gneisses of the Fuping Complex显示文摘The albite rim is present in most felsic gneisses of the Fuping Complex.The presence of the rim indicates the coexistence of plagioclase and K-feldspar in the rock.The rim is formed immediately after the myrmekite,and both textures were derived from the alteration of K-feldspar.The difference is that that there is no quartz present in the rim,and the rim is nearly albite and the anorthite content of the rim plagioclase is substantially lower than that of the myrmekite plagioclase.Formed at 400-500°C the albite rim was derived from the K-feldspar composition adjustment in the late or post-magmatism stage.As the temperature decreased,the equilibrium between K-feldspar and plagioclase could be maintained,and reactions between the minerals occurred.The leucocratic veins in the complex show distinguished magma or migmatitic characteristics.The rim might form in the late magma or deuteric stage.The formation of the rim implies obvious granitic magma-or melt-injection activity.Typical metamorphic rocks cannot produce the rims.Anatexis after medium-high grade metamorphism might be subordinate.If present,the anatexis is water-present,but the rim texture cannot be taken as the symbol of anatexis. | REN Liudong YANG Chonghui DULilin | 2012 | Acta Geologica Sinica(English Edition)2012，86，2： | 4 |
| 5 | Optimal Energy-Efficient Operation of a Metro Train on a Long and Steep Downhill Segment显示文摘Because the standard four-stage operation and con-trol strategy cannot fully utilize the gravitational potential energy of a train operating on a long and steep downhill segment,this paper further improves the method for train operation and control strategy.The improved operation includes three stages of acceleration,coasting-speed limit cruising,and brak-ing.Taking the speed limit,time limit,and distance limit as the constraints,the coasting condition switching point,braking condition switching point,traction coefficient,and braking force coefficient are used as the decision variables.Then,an improved train traction energy consumption model is constructed,and an improved differential evolution algorithm is designed to solve this model.The improved method is used to simulate two long and steep downhill segments of the Nanning metro.The results show that the improved method can meet the requirements of speed limit,time limit,and distance limit.Compared with the standard four-stage operation,the improved train operation and control strategy can reduce train energy consumption by more than 40%on the two long and steep downhill segments;compared with other similar algorithms,the improved algorithm is more suitable for solving the model. | Deqiang He Hanqing Jian Yanjun Chen Jian Miao Zhixiao Luo Chonghui Ren Lang Zhang | 2023 | CSEE Journal of Power and Energy Systems2023，9，6： | 0 |
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