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156篇 您的检索式:作者名="X. Ma"
    题名 作者 年代 出处 被引量
1CO_2浓度变化和气候变化对中国陆地生态系统净初级生产及其平衡的影响(英文)显示文摘本文应用陆地生态系统模型(TEM,4.0)对中国陆地生态系统在目前气候下的净初级生产力,以及在CO2浓度增加和气候变化后的净初级生产力的变化进行了预测。气候变化模型采用三种大气环流模型生成,即:GISS、GFDL和OSU模型。在当前气候条件和CO2浓度(312.5×10-6)下,TEM模型预测中国陆地生态净初级生产力为3,653TgC·a-1(1012gC·a-1)。温带常绿阔叶林是生产力最高的生物区,占有中国净初级生产力的最大比例。NPP的空间格局主要与降水量和温度的空间分布相关联。中国陆地生态系统的年净初级生产力对CO2浓度和气候的变化敏感。在陆地区域尺度上,其年净初级生产力仅在CO2浓度上升至519×10-6的情况下可增加6.0%(219TgC·a-1)。在气候变化而无CO2浓度变化的条件下,净初级生产力的响应在GISS气候方案下表现为1.5%(54.8TgC·a-1)的降低,在GFDL-q气候方案下表现为8.4%(306.9TgC·a-1)的增加。在气候和CO2浓度均发生变化的情况下,净初级生产力有较大程度的增加,在GISS气候方案下的增加比例为18.7%(683TgC·a-1),在GFDL-q气候?Xiao 1,2 , X., J.M.Melillo 1, D.W.Kicklighter 1, Y.Pan 1, A.D.McGuire 3 and J.Helfrich 1 ( 1The Ecosystems Center, Marine Biological Laboratory, Woods Hole, MA 02543, USA) ( 2 The Joint Program on the Science and Policy of Globa 1998植物生态学报1998,22,2:35
2EGF promoter SNPs, plasma EGF levels and risk of breast cancer in Chinese women显示文摘Wang, Y. 2008南京医科大学学报(自然科学版)2008,28,12:32
3A Simple and Reliable Assay for Detecting Specifi c Nucleotide Sequences in Plants Using Optical Thin-fi lm Biosensor Chips显示文摘Here we report the adaptation and optimization of an effi cient, accurate and inexpensive assay that employs custom-designed silicon-based optical thin-fi lm biosensor chips to detect unique transgenes in genetically modi-S. Bai X. Zhong L. Ma W. Zheng L. Fan N. Wei X.W. Deng 2007分子植物育种2007,5,2:13
4EXPLOITATION AND APPLICATIONS OF METASTABLE AUSTENITE MATRIX WEAR ALLOYS显示文摘Fe based cast alloys with double phases structure of m etastable austenite m atrix an d eutecticcarbide M7 C3 were provided with the excellent properties of high abrasion resistance andhigher i m pact toughness . An i m portant reason of high abrasion resistance is hard ness violentincreasing on the m atrix surface because of w ear easily induced m artensite transfor m ation . The exploitation and applications of m etastable austenite m atrix wear alloys of Fe C Cr Nisyste m and Fe C Cr Mn system were described in this paper . The excellent properties of thesealloys w ill be sufficiently indicated by authors’exa m ples . To exploit a class of these alloyswith high abrasion resistance and various im pact toughness for m eeting the requirem ent of dif ferent environ ment , the proble m of the structure design of metastable austenite m atrix wearalloy w as also described in this paper .Y. Q. Ma , Y. H. Qi , X. L. Xu and L. Y. Dai Institute of Metal Material Technology , Dalian Maritime University , Dalian 116026 , China 1999Acta Metallurgica Sinica(English Letters)1999,12,5:12
5Connexin 43 hemichannels protect bone loss during estrogen deficiency显示文摘Estrogen deficiency in postmenopausal women is a major cause of bone loss,resulting in osteopenia,osteoporosis,and a high risk for bone fracture.Connexin 43 (Cx43) hemichannels (HCs) in osteocytes play an important role in osteocyte viability,bone formation,and remodeling.We showed here that estrogen deficiency reduced Cx43 expression and HC function.To determine if functional HCs protect osteocytes and bone loss during estrogen deficiency,we adopted an ovariectomy model in wild-type (WT) and two transgenic Cx43 mice:R76W (dominant-negative mutant inhibiting only gap junction channels) and Cx43 Δ130–136 (dominant-negative mutant compromising both gap junction channels and HCs).The bone mineral density (BMD),bone structure,and histomorphometric changes of cortical and trabecular bones after ovariectomy were investigated.Our results showed that the Δ130–136 transgenic cohort had greatly decreased vertebral trabecular bone mass compared to WT and R76W mice,associated with a significant increase in the number of apoptotic osteocyte and empty lacunae.Moreover,osteoclast surfaces in trabecular and cortical bones were increased after ovariectomy in the R76W and WT mice,respectively,but not in Δ130–136 mice.These data demonstrate that impairment of Cx43 HCs in osteocytes accelerates vertebral trabecular bone loss and increase in osteocyte apoptosis,and further suggest that Cx43 HCs in osteocytes protect trabecular bone against catabolic effects due to estrogen deficiency.Liang Ma Rui Hua Yi Tian Hongyun Cheng Roberto Jose Fajardo Joseph J. Pearson Teja Guda Daniel Brian Shropshire Sumin Gu Jean X. Jiang 2019Bone Research2019,7,2:11
6Effects of temperature and thermally-induced microstructure change on hydraulic conductivity of Boom Clay显示文摘Boom Clay is one of the potential host rocks for deep geological disposal of high-level radioactive nuclear waste in Belgium. In order to investigate the mechanism of hydraulic conductivity variation under complex thermo-mechanical coupling conditions and to better understand the thermo-hydromechanical(THM) coupling behaviour of Boom Clay, a series of permeability tests using temperaturecontrolled triaxial cell has been carried out on the Boom Clay samples taken from Belgian underground research laboratory(URL) HADES. Due to its sedimentary nature, Boom Clay presents acrossanisotropy with respect to its sub-horizontal bedding plane. Direct measurements of the vertical(Kv)and horizontal(Kh)hydraulic conductivities show that the hydraulic conductivity at 80℃ is about 2.4 times larger than that at room temperature(23℃), and the hydraulic conductivity variation with temperature is basically reversible during heatingecooling cycle. The anisotropic property of Boom Clay is studied by scanning electron microscope(SEM) tests, which highlight the transversely isotropic characteristics of intact Boom Clay. It is shown that the sub-horizontal bedding feature accounts for the horizontal permeability higher than the vertical one. The measured increment in hydraulic conductivity with temperature is lower than the calculated one when merely considering the changes in water kinematic viscosity and density with temperature. The nuclear magnetic resonance(NMR) tests have also been carried out to investigate the impact of microstructure variation on the THM properties of clay. The results show that heating under unconstrained boundary condition will produce larger size of pores and weaken the microstructure. The discrepancy between the hydraulic conductivity experimentally measured and predicted(considering water viscosity and density changes with temperature) can be attributed to the microstructural weakening effect on the thermal volume change behaviour of Boom Clay. Based on the experimental results, a hydraulic conductivity evolution model is proposed and then implemented in ABAQUS. Three-dimensional(3D) numerical simulation of the admissible thermal loading for argillaceous storage(ATLAS) Ⅲ in situ heating test has been conducted subsequently, and the numerical results are in good agreement with field measurements.W.Z. Chen Y.S. Ma H.D. Yu F.F. Li X.L. Li X. Sillen 2017Journal of Rock Mechanics and Geotechnical Engineering2017,9,3:7
7Pseudomonas stutzeri as a novel biocatalyst for pyruvate production from DL-lactate显示文摘Hao, J. R. Ma, C. Q. Gao, C. Qiu, J. H. Wang, M. Zhang, Y. N. Cui, X. Xu, P. 2007中国生物学文摘2007,21,4:4
8TWO METHODS FOR ASSESSMENT OF RESIDUAL LIFE OF HK-40 FURNACE TUBES显示文摘1.IntroductionThehightemperaturefurnacetubesfabricatedfromthecentrifugalcastresistantausteniticsteelofHK-40(25Cr-20Ni-0.4C)an...F.Z. Shen. G.X. Ma and X. Ling Nanjing University of Chemical Technology, Nanjing 210009, China X. Yang Jing Ling Petrochemical Corporation, Nanjing 210046, China X.Z. Zhang, J. Ruan and Y. Lu Lutianhua Group Incorporated, Luzhou 646300, China 1999Acta Metallurgica Sinica(English Letters)1999,12,1:4
9A New Perspective about Climate Change显示文摘K. B. Mao Y. Ma T.R. Xu Q. Liu J Q. Han L. Xia X. Y. Shen T. J. He 2015地球科学期刊(中英文版)2015,5,1:4
10First-Principles Study of the Influence of Lattice Misfit on the Behavior and the Ductility Effect of Hafnium in Ni-Ni3AI System显示文摘Y. Wu J. Guo W. Zhang X. Ma Q. Zhang J. Hou R. Huang X. Liu 2014Acta Metallurgica Sinica(English Letters)2014,27,1:3
11Optimizing surface-engineered ultra-small gold nanoparticles for highly efficient miRNA delivery to enhance osteogenic differentiation of bone mesenchymal stromal cells显示文摘骨头的 osteogenic 区别的规定间充质的 stromal 房间(BMSC ) 戏在骨头新生的一个关键角色。作为小非编码的 RNA, microRNAs (miRNAs ) 玩在通过调整 target-mRNA 的干细胞区别的一个重要角色表示。不幸地,到 BMSC 的 miRNAs 的高度有效、安全的交货仍然保持调整他们的 osteogenic 区别挑战性。常规无机的 nanocrystals 由于他们预防的更大的尺寸显示出增加的毒性肾的清理。这里,我们开发了新奇、设计表面的、极端小的金 nanoparticles (USAuNPs, < 10 nm ) 用作高度有效的 miR-5106-delivery 系统到启用 BMSC 区别的规定。我们与 polyethylenimine (PEI ) 和 liposomes 利用了 AuNPs 涂的 layer-by-layer 的效果(脂肪) 提高 miR-5106-delivery 活动和随后的 BMSC 区别能力。PEI 涂、脂肪涂的 AuNPs (Au@PEI@Lipo ) 显示出可以忽略的 cytotoxicity,好 miRNA-5106-binding 亲密关系,到 BMSC 的 miRNAs 的高度有效的交货,和长期的 miRNA 表示(21 天) 。与商业 Lipofectamine 3000 和 25 kD PEI 相比,另外,优化 Au@PEI@Lipo-miR-5106 nanocomplexes 显著地通过 Sox9 抄写因素的激活提高了 BMSC 区别进像造骨细胞的房间。我们的调查结果为织物作为高度有效的 miRNA 交货平台为极端小的无机的 nanoparticles 的合理设计揭示有希望的策略新生和疾病治疗。Meng Yu Bo Lei Chuanbo Gao Jin Yan Peter X. Ma 2017Nano Research2017,10,1:3
12Nitrile biotransformations for the practical synthesis of highly enantiopure azido carboxylic acids and amides, ‘click’ to functionalized chiral triazoles and chiral beta-amino acids显示文摘Ma, D. Y. Wang, D. X. Zheng, Q. Y. Wang, M. X. 2007中国生物学文摘2007,21,3:3
13Enhancing enzymatic activity of penicillin G acylase by coexpressing pcm gene显示文摘Wang, T. W. Zhu, H. Ma, X. Y. Fei, Z. Y. Ma, Y. S. Wei, D. Z. 2007中国生物学文摘2007,21,4:3
14Ethyl pyruvate significantly inhibits tumour necrosis factor‐α, interleukin‐1β and high mobility group box 1 releasing and attenuates sodium taurocholate‐induced severe acute pancreatitis associated with acute lung injury显示文摘Z.‐G. Luan J. Zhang X.‐H. Yin X.‐C. Ma R.‐X. Guo 2013Clin Exp Immunol2013,,3:2
15Genetic Diversity Analysis of Cultured Populations of Jade Perch (Scortum bacoo) in China Using AFLP Markers显示文摘K. C. Chen L. S. Ma Y. Shi J. Zhao X. P. Zhu 2011Journal of Agricultural Science and Technology2011,5,4:2
16A Clinical Study of HB sAg‐Activated Dendritic Cells and Cytokine‐Induced Killer Cells During the Treatment for Chronic Hepatitis B显示文摘Y.‐J. Ma M. He J.‐A. Han L. Yang X.‐Y. Ji 2013Scand J Immunol2013,,4:2
17EFFECT OF THE CONTROLLED ROLLING CONTROLLED COOLING ON STRENGTH AND DUCTILITY OF THE BAINITE MICRO ALLOYED ENGINEERING STEEL显示文摘The continuous cooling transformation of hot deformation austenite austenite of test steel and the effect of different processing schedules of controlled rolling and controlled cooling on the strength and ductility have been studied. The theory and the experiment base are presented for controlled rolling and controlled cooling of the SBL micro alloyed engineering steel.Z. Li, G. D. Wang,X. H. Liu and C. Y. Ma The State Key Lab. of Rolling Technology and Automation, Northeastern Univarsity, Shenyang 110006 China 2000Acta Metallurgica Sinica(English Letters)2000,13,2:2
18Development of constitutive relationship model of Ti600 alloy using artificial neural network显示文摘Y. Sun W.D. Zeng Y.Q. Zhao Y.L. Qi X. Ma Y.F. Han 2010Computational Materials Science2010,,3:2
19Novel antibacterial nanofibrous PLLA scaffolds显示文摘Kai Feng Hongli Sun Mark A. Bradley Ellen J. Dupler William V. Giannobile Peter X. Ma 2010Journal of Controlled Release2010,,3:2
20High Spin Band Structure in ^112Ru显示文摘车兴来 朱胜江 J. H. Hamilton A. V. Ramayya J. K. Hwang J. O. Rasmussen Y. X. Luo 陈水静 李明亮 丁怀搏 禹英男 I. Y. Lee W. C. Ma 2006Chinese Physics Letters2006,23,2:2
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