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| 1 | ^(14)C measurement of forest soils in Dinghushan Biosphere Reserve显示文摘Organic carbon in forest soils of Qingyunsi and Wukesong profiles can be divided into fast and slow components. Δ14C values of these profiles decrease with increasing of depth. The Δ14C values in 30—40 cm depth interval of Wukesong profile are decreasing sharply until a very low value,showing that a strong geological environment change occurred about 1 560 years ago. The 14C apparent ages of Wukesong profile show that the coniferous and broad-leaf mixed forests around Wukesong profile have been developing since 425 a BP, which is consistent with historical documents. The penetrating depths of 'bomb 14C' in Qingyunsi and Wukesong profiles are 10 and 20 cm, respectively. | SHEN Chengde , LIU Dongsheng (LIU Tungsheng) , PENG Shaolin, SUN Yanmin , JIANG Mantao , Yl Weixi , XING Changping , GAO Quanzhou , LI Zhi’an and ZHOU Guoyi Guangzhou Institute of Geochemisry, Chinese Academy of Sciences, Guangzhou 510640, China Institute of Geology, Chinese Academy of Sciences , Beijing 100029, China South China Institute of Botany, Chinese Academy of Sciences, Guangzhou 510650, China | 1999 | Chinese Science Bulletin1999，44，3： | 7 |
| 2 | Vegetation evolution on the central Chinese Loess Plateau since late Quaternary evidenced by elemental carbon isotopic composition显示文摘There are many controversial issues in loess studies such as natural vegetation types on the Chinese Loess Plateau during the historical periods and the spatial and temporal evolution of C3/C4 plants. Elemental carbon isotopic composition (δ13Cec) in the loess section may offer new evidence for these problems. Elemental carbon (EC) is produced by incomplete combustion of vegetation, and its carbon isotopic composition has a very small difference from that of the formal vegetation, then δ13Cec can be used as a record to recover the changes of vegetation. Elemental carbon was extracted by applying the oxidation method from the loess-paleosol sequence in the central Chinese Loess Plateau, and its carbon isotope composition was analyzed by the isotope mass spectrometer. The results showed that the vegetation in this region was a mixed type of C3 and C4 plants, dominated with C3 plants in most of the time. Since late Quaternary, C3/C4 plants may not follow a simple glacial-interglacial cycle mode on the Chinese Loess Plateau, but showing fluctuations. C3 plants increased gradually in L4 period, and more C3 plants occurred during S3 period, and C4 plants increased again during L3―L2 periods, after that, C3 plants dominated again during S1―S0 periods. During periods of paleosol development, C3 plants were abundant in S3 and S1, and there were more C4 plants in S2 and S0. During periods of loess sedimen- tation, there were more C3 plants in L4 and L1, and there were more C4 plants in L3 and L2. On the or- bital timescale, the vegetation variations revealed by δ13Cec record are consistent with the results of pollen data and also similar to the results obtained by organic carbon isotopic composition since the last glacial period. | ZHOU Bin SHEN ChengDe ZHENG HongBo ZHAO MeiXun SUN YanMin | 2009 | Chinese Science Bulletin2009，54，12： | 6 |
| 3 | The elemental carbon record in Weinan loess section since the last 21 ka显示文摘We studied the records of elemental carbon (EC) of the last 21 ka in the Weinan loess section, Shanxi Province. The variations of EC abundance and δ13CEC value along with depth (or age) were presented. There are four large peaks of EC abundance around the following years: 20.16 ka, 17.76 ka, 11.97 ka and 4.49 ka. Climatic situation was changed rapidly during these periods. The peaks around 11.97 ka and 20.16 ka are particularly sharp, occurring over intervals of tens to hundreds of years, which could represent short-duration intense events. δ13CEc values in the upper 4 m of the Weinan loess section vary between -11.71‰ and -21.34‰, which suggests that the vegetation pattern of the last 21 ka on the Loess Plateau is G4-dominated grasses. | YANG Ying SHEN Chengde YI Weixi SUN Yanmin LIU Dongsheng | 2001 | Chinese Science Bulletin2001，46，18： | 5 |
| 4 | ^(10)Be/~7Be implies the contribution of stratosphere-troposphere transport to the winter-spring surface O_3 variation observed on the Tibetan Plateau显示文摘10Be/7Be is a stratospheric sensitive tracer.In this paper,measurements of 10Be/7Be and surface O3 from October 2005 to May 2006 at Mt.Waliguan (hereafter WLG,100.898°E,39.287°N,3810 m,a.s.l.),China global atmospheric watch (GAW) observatory,are introduced and used to investigate the stratosphere-troposphere transport (STT) and its impact on surface O3 on the Tibetan Plateau.The results show that the magnitude of STT is weak in winter,followed by strengthening from the end of winter to the middle of spring (from mid February to mid April) with large increases in 10Be,7Be,10Be/7Be and surface O3.At the end of spring (from the end of April to mid May in this paper),the STT weakened,and the continuous increase of surface O3 at WLG is produced by tropospheric photochemistry reactions. | ZHENG XiangDong SHEN ChengDe WAN GuoJiang LIU KeXin TANG Jie XU XiaoBin | 2011 | Chinese Science Bulletin2011，56，1： | 5 |
| 5 | Carbon isotopic composition and its implications on paleoclimate of the underground ancient forest ecosystem in Sihui,Guangdong显示文摘We present the carbon isotopic composition of the total organic carbon(TOC) and fine roots in the sedimentary profile from the underground ancient forest in Sihui to study the climatic and environmental changes from 4.5 ka BP to 0.6 ka BP.Results show that C3 plant was the main vegetation from 4.5 ka BP to 0.6 ka BP in this region.The ancient forest began to develop in the wetland at around 4 ka BP and disappeared together with the wetland at about 3.0 ka BP,implying that the climate had changed greatly at around 3.0 ka BP.As indicated by the simulation results,the content of atmospheric CO2 increased slightly during 3.5 ka BP and 3.0 ka BP,implying climate warming during that period.The interval of radiocarbon age between 3.0 ka BP and 1.2 ka BP was possibly caused by the strong erosion when the block was lifted in the neotectonic movement.From 1.2 ka BP to 0.6 ka BP,the region remained in terrestrial sedimentary environment,and the surface plant biomass declined gradually.Drought caused by the climate change was the likely cause for the disappearance of the ancient forest.South transition of Intertropical Convergence Zone(ITCZ) was probably the main mechanism for the climate change. | Ping Ding ChengDe Shen Ning Wang WeiXi Yi KeXin Liu XingFang Ding DongPo Fu | 2009 | Science China Earth Sciences2009，52，5： | 4 |
| 6 | Carbon isotopic composition,turnover and origins of soil CO_2 in a monsoon evergreen broadleaf forest in the Dinghushan Biosphere Reservoir,South China显示文摘Carbon isotopic compositions of soil CO2 in rainy season (July) from two natural soil profiles (DHLS & DHS) in the monsoon evergreen broadleaf forest in the Dinghushan Biosphere Reservoir (DBR),South China,are presented.Turnover and origins of soil CO2 are preliminarily discussed in this paper.Results show that the content of soil CO2 varies between 6120 and 18718 ppmv,and increases with increasing depth until 75 cm,and then it declines.In DHLS,soil CO2 δ 13C ranges from -24.71‰ to -24.03‰,showing a significant inverse correlation (R2=0.91) with the soil CO2 content in the same layer.According to a model related to soil CO2 δ 13C,the soil CO2 is mainly derived from the root respiration (>80%) in DHLS.While in DHS,where soil CO2 δ 13C ranges from -25.19‰ to -22.82‰,soil CO2 is primarily originated from the decomposition of organic matter (51%–94%),excluding the surface layer (20 cm,90%).Radiocarbon data suggest that the carbon in soil CO2 is modern carbon in both DHLS and DHS.Differences in 14C ages between the 'oldest' and 'youngest' soil CO2 in DHLS and DHS are 8 months and 14 months,respectively,indicating that soil CO2 in DHLS has a faster turnover rate than that in DHS.The Δ14C values of soil CO2,which range between 100.0‰ and 107.2‰ and between 102.5‰ and 112.1‰ in DHLS and DHS,respectively,are obviously higher than those of current atmospheric CO2 and SOC in the same layer,suggesting that soil CO2 is likely an important reservoir for Bomb-14C in the atmosphere. | DING Ping SHEN ChengDe WANG Ning YI WeiXi DING XingFang FU DongPo LIU KeXin ZHAO Ping | 2010 | Chinese Science Bulletin2010，55，23： | 4 |
| 7 | A biomass burning record from the Lingtai Loess Section during the last 370 ka and implication for climate and environment显示文摘The history of natural fire and its rela- tionship with climate and vegetation are revealed from the content of elemental carbon and associated pollen data and paleoclimatic substitutive indicators for the loess of Lingtai Section in the last 370 ka BP. The study indicates that intense episodes of vegeta- tion fires occurred during the interim especially when the climate was changing from wet to drought. The average content of elemental carbon in the intergla- ciers is higher than that in the glaciers, which coin- cides with the biomass change locally (or globally). The content of elemental carbon increases in the stage around 130 ka BP, indicating that the vegeta- tion and climate pattern have changed, which may contribute to the variation of CO2. As a whole, the content of elemental carbon increasing with the time reflects the increasing aridity trend to some degree. In addition, the occurrence of the maximum peak and the highest average content of elemental carbon in the Holocene reflects the occurrence of a rapid cli- mate event in 5900 a BP and more frequent fires caused by anthropic activities. | ZHOU Bin SHEN Chengde SUN Yanmin YANG Ying YI Weixi | 2006 | Chinese Science Bulletin2006，51，17： | 2 |
| 8 | Apparent ages of suspended sediment and soil erosion of the Pearl River (Zhujiang) drainage basin显示文摘The carbon isotopic composition (Δ 14 C,δ 13 C) and apparent ages of suspended sediment were determined in the Pearl River in the years 1998,2000 and 2005.These results indicate that suspended POC consists mostly of young carbon and some 'old carbon'.Apparent ages of suspended POC range from 540 to 2050 a BP.The apparent ages are older in the Xijiang and Beijiang Rivers,while these values are variable in the Dongjiang River,including old and young samples.The suspended POCδ 13 C values increase with increasing Δ 14 C in the Pearl River,indicating that its source is soil and bedrock from depths under 15 30 cm.Since the organic carbon of the surface soil is quickly decomposed when it enters the rivers,its carbon isotopic characteristics are insignificant in suspended sediment.In the Pearl River drainage basin,there are areas with more severe soil erosion than others.For example,erosion is much more severe in the Xijiang River drainage basin when compared to the light soil erosion in the Dongjiang River drainage basin. | WEI XiuGuo SHEN ChengDe LI NingLi WANG FuShun DING Ping WANG Ning GUO ZhiXing LIU KeXin | 2010 | Chinese Science Bulletin2010，55，15： | 2 |
| 9 | Riverine organic carbon in the Xijiang River ( South China) : seasonal variation in content and flux budget 显示文摘 | GAO Quanzhou TAO Zhen SHEN Chengde | 2002 | Environmental Geology2002，41，7： | 1 |
| 10 | Quantitative estimates of pedogenic ferromagnetic mineral formation in Chinese Loess and paleoclimatic implications显示文摘 | Heller F Shen Chengde Beer J | | 0，，2： | 1 |
| 11 | ~4C as a tool for evaluating riverine POC sources and erosion of the Zhujiang (Pearl River) drainage basin, South China 显示文摘 | Wei Xiuguo Yi Weixi Shen Chengde Yechieli Y Li Ningli Ding Ping Wang Ning Liu Kexin | 2010 | Nucl Instrum Methods Phys Res Sect B2010，268，7： | 1 |
| 12 | Spatial and temporal distribution of carbon isotopes in soil organic matter at the Dinghushan Biosphere Reserve, South China显示文摘 | Qingqiang Chen Chengde Shen Yanmin Sun Shaolin Peng Weixi Yi Zhi’an Li Mantao Jiang | 2005 | Plant and Soil (-)2005，，1： | 1 |
| 13 | Additive manufacturing of bone scaffolds显示文摘Additive manufacturing(AM)can obtain not only customized external shape but also porous internal structure for scaffolds,both of which are of great importance for repairing large segmental bone defects.The scaffold fabrication process generally involves scaffold design,AM,and post-treatments.Thus,this article firstly reviews the state-of-the-art of scaffold design,including computer-aided design,reverse modeling,topology optimization,and mathematical modeling.In addition,the current characteristics of several typical AM techniques,including selective laser sintering,fused deposition modeling(FDM),and electron beam melting(EBM),especially their advantages and limitations are presented.In particular,selective laser sintering is able to obtain scaffolds with nanoscale grains,due to its high heating rate and a short holding time.However,this character usually results in insufficient densification.FDM can fabricate scaffolds with a relative high accuracy of pore structure but with a relative low mechanical strength.EBM with a high beam-material coupling efficiency can process high melting point metals,but it exhibits a low-resolution and poor surface quality.Furthermore,the common post-treatments,with main focus on heat and surface treatments,which are applied to improve the comprehensive performance are also discussed.Finally,this review also discusses the future directions for AM scaffolds for bone tissue engineering. | Youwen Yang Guoyong Wang Huixin Liang Chengde Gao Shuping Peng Lida Shen Cijun Shuai | 2019 | International Journal of Bioprinting2019，5，1： | 1 |
| 14 | Single-molecule imaging of dinitrogen molecule adsorption on individual iron phthalocyanine显示文摘Nitrogen fixation is a vital process for both nature and industry.Whereas the nitrogenase can reduce nitrogen in ambient environment in nature,the industrialized Haber-Bosch process is a high temperature and high-pressure process.Since the discovery of the first dinitrogen complex in 1965,many dinitrogen complexes are prepared in a homogeneous solution to mimic the nitrogenase enzyme in nature.However,studies of the heterogeneous process on surface are rarely addressed.Moreover,molecular scale characterization for such dinitrogen complex is lacking.Here,we present a simple model system to investigate,at the single-molecule level,the binding of dinitrogen on a surface confined iron phthalocyanine(FePc)monolayer through the combination of in-situ low-temperature scanning tunneling microscopy(LT-STM)and X-ray photoelectron spectroscopy(XPS)measurements.The iron center in FePc molecule deposited on Au(111)and highly oriented pyrolytic graphite(HOPG)surface can adsorb dinitrogen molecule at room temperature and low pressure.A comparative study reveals that the adsorption behaviors of FePc on these two different substrates are identical.Chemical bond is formed between the dinitrogen and the Fe atom in the FePc molecule,which greatly modifies the electronic structure of FePc.The bonding is reversible and can be manipulated by applying bias using a STM tip or by thermal annealing. | Chengding Gu Jia Lin Zhang Jian Qiang Zhong Qian Shen Xiong Zhou Kaidi Yuan Shuo Sun Xu Lian Zhirui Ma Wei Chen | 2020 | Nano Research2020，13，9： | 1 |
| 15 | Holocene Megathermal Abrupt Environmental Changes Derived from 14C Dating of a Coral Reef at Leizhou Peninsula, South China Sea显示文摘 | Shen Chengde Yi Weixi Yu Kefu | 2004 | Nucl Instr and Meth2004，，： | 1 |
| 16 | Organic matter turnover rates and CO2 flux from or- ganic matter decomposition of mountain soil profiles in tile subtropical area,south China显示文摘 | Chen Qingqiang Sun Yanmin Shen Chengde | 2002 | Catena2002，49，3： | 1 |
| 17 | Presence of multiple abnormal immunologic markers is an independent prognostic factor of diffuse large B-cell lymphoma显示文摘Autoimmune diseases (ADs) increase the risk of non-Hodgkin's lymphoma and contribute to poor prognosis of patients. However, the association between immunologic markers and clinical outcome has rarely been investigated. This study aims to analyze the prognostic value of pretreatment immunologic markers in newly diagnosed patients with diffuse large B-cell lymphoma (DLBCL). We retrospectively reviewed the data on 502 patients with DLBCL treated in our institution from January 2013 to March 2018. Survival functions were estimated using Kaplan Meier method and Cox regression model. The 3-year progression free survival (PFS) and overall survival (OS) rates were 70.2% and 80.9%, respectively, and the complete remission (CR) rate was 78.1%. Among the patients, those with multiple (≥3) abnormal immunologic markers had significantly shorter 3-year PFS (52.7% vs. 77.3%, P < 0.001) and OS (68.5% vs. 85.8%, P=0.001) than those without multiple abnormal immunologic markers.Multivariate analysis revealed that the presence of multiple abnormal immunologic markers and the elevated serum levels of lactate dehydrogenase were the independent adverse prognostic factors for PFS (P= 0.008, P < 0.001) and OS (P = 0.003, P < 0.001). Meanwhile, advanced Ann Arbor stage was an independent adverse prognostic factor for PFS (P= 0.001) and age > 60 years for OS (P= 0.014). In conclusion, the immunologic status was closely related to lymphoma progression, and this study provides new insights into the risk stratification of patients with DLBCL. | Yiwen Cao Zhenhua Liu Wen Wu Ying Qian Qin Shi Rong Shen Binshen Ouyang Pengpeng Xu Shu Cheng Jin Ye Yiming Lu Chaofu Wang Chengde Yang Li Wang Weili Zhao | 2019 | Frontiers of Medicine2019，13，1： | 0 |
| 18 | Mass and isotopic concentrations of water-insoluble refractory carbon in total suspended particulates at Mt.Waliguan Observatory(China)显示文摘Mass concentration and isotopic values δ^(13)C and ^(14)C are presented for the water-insoluble refractory carbon(WIRC) component of total suspended particulates(TSP),collected weekly during 2003,as well as from October 2005 to May 2006 at the WMO-GAW Mt.Waliguan(WLG) site.The overall average WIRC mass concentration was(1183±120)ng/m^3(n = 79),while seasonal averages were 2081 ±1707(spring),454±205(summer),650±411(autumn),and 1019±703(winter) ng/m3.Seasonal variations in WIRC mass concentrations were consistent with black carbon measurements from an aethalometer,although WIRC concentrations were typically higher,especially in winter and spring.The δ^(13)C PDB value(-25.3 ± 0.8)%.determined for WIRC suggests that its sources are C_3 biomass or fossil fuel combustion.No seasonal change in δ^(13)C PDB was evident.The average percent Modern Carbon(pMC) for ^(14)C in WIRC for winter and spring was(67.2 ± 7.7)%(n = 29).Lower pMC values were associated with air masses transported from the area east of WLG,while higher pMC values were associated with air masses from the Tibetan Plateau,southwest of WLG.Elevated pMC values with abnormally high mass concentrations of TSP and WIRC were measured during a dust storm event. | Xiangdong Zheng Chengde Shen Guojiang Wan Jie Tang Kexin Liu | 2015 | Particuology2015，13，3： | 0 |
| 19 | Concentration and seasonal variation of ^(10)Be in surface aerosols of Lhasa,Tibet显示文摘Thirty samples of total suspended particles were collected at a site in western part of Lhasa,Tibet from August 2006 to July 2007.The 10Be concentrations were determined by Accelerator Mass Spectrometer (AMS).Analysis of correlation between 10Be concentrations and meteorological factors revealed that the wet scavenging has little effect on 10Be.10Be can be used as a proxy of transport processes of the upper atmosphere over the Tibetan Plateau.Analysis of correlation between 10Be concentrations and NCEP reanalysis data demonstrated that higher 10Be concentrations in spring were probably caused by the atmosphere exchange from stratosphere to troposphere during February to June.Lower 10Be concentrations during August to September were consistent with the synchronous lower O3 values,suggestive of both 10Be and O3 were probably influenced by the atmosphere exchange from troposphere to stratosphere. | HUANG Jie KANG ShiChang SHEN ChengDe CONG ZhiYuan LIU KeXin WANG Wei LIU LiChao | 2010 | Chinese Science Bulletin2010，55，23： | 0 |
| 20 | An ignored key link in greenhouse effect:Soil and soil CO_(2) slow heat loss显示文摘The ever-increasing atmospheric CO_(2) concentration is a key driver of modern global warming.However,the low heat capacity of atmosphere and strong convection processes in the troposphere both limit heat retention.Given the higher heat capacity and CO_(2) concentration in soil compared to the atmosphere,the direct contributions of soil to the greenhouse effect may be significant.By experimentally manipulating CO_(2) concentrations both in the soil and the atmosphere,we demonstrated that the soil-retained heat and the slower soil heat transmission decrease the amount of heat energy leaking from the earth.Furthermore,the soil air temperature was affected by soil CO_(2) concentration,with the highest value recorded at 7500 ppm CO_(2).This study indicates that soil and soil CO_(2),together with atmospheric CO_(2),play a crucial role in the greenhouse effect.The spatial and temporal heterogeneity of soils and soil CO_(2) should be further investigated,given their potentially significant influence on global climate change. | Weixin Zhang Chengde Yu Zhifeng Shen Shu Liu Suli Li Yuanhu Shao Shenglei Fu | 2020 | Soil Ecology Letters2020，2，4： | 0 |
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