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    题名 作者 年代 出处 被引量
1Responses of Soil Microbial Community Structure and Diversity to Agricultural Deintensification显示文摘Using a scheme of agricultural fields with progressively less intensive management (deintensification), different manage- ment practices in six agroecosystems located near Goldsboro, NC, USA were tested in a large-scale experiment, including two cash-grain cropping systems employing either tillage (CT) or no-tillage (NT), an organic farming system (OR), an integrated cropping system with animals (IN), a successional field (SU), and a plantation woodlot (WO). Microbial phos- pholipid fatty acid (PLFA) profiles and substrate utilization patterns (BIOLOG ECO plates) were measured to examine the effects of deintensification on the structure and diversity of soil microbial communities. Principle component analyses of PLFA and BIOLOG data showed that the microbial community structure diverged among the soils of the six systems. Lower microbial diversity was found in lowly managed ecosystem than that in intensive and moderately managed agro- ecosystems, and both fungal contribution to the total identified PLFAs and the ratio of microbial biomass C/N increased along with agricultural deintensification. Significantly higher ratios of C/N (P < 0.05) were found in the WO and SU systems, and for fungal/bacterial PLFAs in the WO system (P < 0.05). There were also significant decreases (P < 0.05) along with agricultural deintensification for contributions of total bacterial and gram positive (G+) bacterial PLFAs. Agricultural deintensification could facilitate the development of microbial communities that favor soil fungi over bacteria.ZHANG Wei- Jian RUI Wen-Yi C. TU H. G. DIAB F. J. LOUWS J. P. MUELLER N. CREAMER M. BELL M.G. WAGGER S. HU 2005Pedosphere2005,15,4:29
2钠钾合金高温热管性能试验研究显示文摘提出了以钠钾合金作工质生产高温热管的思想,并通过启动特性、等温性和传热性能试验。捷曼尔M.G. 胡亚才 冯踏青 屠传经 1999浙江大学学报(自然科学版)1999,33,4:17
3金的硫代硫酸盐浸出法评述显示文摘本文从浸出机理、热力学、硫代硫酸盐稳定性和金的回收方法等方面评述了金和银的硫代硫酸盐浸出工艺。讨论了该法在不同类型矿石处理中的应用和过程参数的选择。硫代硫酸盐浸出法是用铜作催化剂的浸出法 ,它比常规氰化法有一些优点。硫代硫酸盐浸出法无毒 ,金的溶解速度比常规氰化法快 ,外来阳离子干扰小 ,处理复杂矿石和含碳矿石金的回收率高。此外 ,硫代硫酸盐比氰化物便宜。由于多种络合配位体 (如氨和硫代硫酸盐 )、Cu(Ⅰ ) /Cu(Ⅱ )氧化还原对的同时存在和硫代硫酸盐在溶液中的稳定性 ,氨 -硫代硫酸盐 -铜体系的化学很复杂。但是 ,只要使浸出液保持适当的硫代硫酸盐、氨、铜和氧的浓度 ,也就是保持适当的Eh和pH条件 ,硫代硫酸盐浸出法是可以控制的。很多文献中报导的硫代硫酸盐浸出条件都证实 ,该法药剂的耗量很大。应对在低药剂浓度下 ,延长浸出时间 ,降低药剂消耗进一步研究。对于高品位矿石和难选硫化矿石 ,为了使金解离 ,一般需要预处理 ,并且还应该进行硫代硫酸盐现场制造工艺的研究。这可降低硫代硫酸盐的耗量 ,以便通过硫化矿物的基质氧化使金很好地解离出来。金属置换法、树脂法、个别情况下的活性炭吸附法可用于从硫代硫酸盐溶液中回收金。用树脂从溶液中回收金比较有前途 ,但是 ,还需要?M.G.艾尔莫尔 黎林 李长根 2001国外金属矿选矿2001,38,5:17
4美国的民族集团和民族性——哈佛的观点显示文摘一1980年晚期出版的《美国民族集团哈佛百科全书》部分地说来是“民族遗产研究计划”的副产物;该计划是美国联邦政府根据1965年初级与中级教育法案修正案(第Ⅸ条)于1972年开始实行的。正如该法案修正案第901款所述,民族遗产研究计划(EHSP)的根据和目的是为了保证有志于“M.G.史密斯 何宁 1983世界民族1983,,6:13
5栗疫病菌的营养体亲和性基因和dsRNAs对病毒传播的影响显示文摘研究了栗疫病菌[Cryphonectriapaasitica(murr.)Barr]的营养体系和性基因及dsRNA病毒对菌株间病毒特征传播的影响。试验选用已知4个VC基因座位的15个VC基因型菌株和3种dsRNA病毒,通过含病毒菌株与野生型菌株的配对培养,将病毒逐个转入不同VC基因型菌株。将不同VC基因型的含病毒菌株与具特定VC基因差异的野生型菌株配对培养,根据培养两周后野生型菌株培养性状的改变与否,统计菌株间的病毒传播率。结果表明,各个VC基因对菌株间病毒传播的影响不同;存在2个VC基因差异的菌株间病毒传播率低于相差1个VC基因的;病毒在相差1个VC基因的菌株间的传播多具单向性;不同类型的病毒在菌株间的传播率也有差异。王克荣 成桂英 刘怡君 M.G.米格鲁姆 1997菌物系统1997,16,1:12
64种栓塞材料行子宫动脉栓塞术后增强MRI的比较显示文摘目的 对子宫动脉栓塞术治疗后的子宫肌瘤病人行MR增强检查,验证并非所有栓塞材料具有等同效果的假设。方法 本研究获机构审查委员会批准,免除知情同意,符合HIPAA法案。84例行6个月MRI随访的女性病人被纳入本回顾性研究,分别采用Contour PVA颗粒(25例)、Contour SE颗粒(23例)、Embosphere微球(19例)、Bead Block微球(17例)治疗。S.D.Abramowitz G.M.Israel S.M.McCarthy J.S.Pollak R.I.White M.G. Tal 朱玉兆 2009国际医学放射学杂志2009,32,2:11
7中国东部栗疫病菌群体的遗传分化显示文摘本实验采用RFLP技术,对中国东部栗疫病菌(Cryphonectria parasitica)进行了群体遗传结构的研究。313个参试菌株来自10个省(市)的16个群体(子群体),样本分布在北纬24°N—41°N。各菌株的DNA分别用限制性内切酶Pst Ⅰ和EcoR Ⅰ酶切,先后以10个低拷贝DNA探针和1个DNA指纹图谱探针进行了杂交和检测。结果表明,两个探针(pCB29和pMS29.1)的杂交图谱呈单态性;探针pCB19的杂交图谱显示,菌株DNA以PstⅠ酶切的为单态性,以EcoR Ⅰ酶切的则呈多态性;其他7个低拷贝探针的杂交图谱都呈多态性(Pst Ⅰ酶切)、指纹图谱探针的检测结果显示,辽宁凤城群体的菌株与中国东部其他群体的菌株相比,具有更多的限制性杂交片段,菌株间的遗传变异性也更大。王克荣 M.G.米格鲁姆 1996真菌学报1996,15,2:9
8Mineralogical, REE-geochemical and fluid inclusion studies on some uranium occurrences, Gabal Gattar, Northeastern Desert, Egypt显示文摘Altered granite occurrences (GII and GV) at Gabal (G.) Gattar are the most important mineralized rocks hosting U-mineralization in Egypt. This mineralized granite is affected by multi-stage hydrothermal alteration proc-esses along brittle structures. This alteration comprises pre-ore alkali-metasomatism and ore-stage hydrothermal hematitization, silicification, kaolinitization, fluoritization, carbonatization and episyenitization. Autoradiographic examination indicates that primary uranium mineralization is present as massive or disseminated ores along tectonic fractures, interstitially in granular minerals, and as cements of breccias. Uraninite, pitchblende and coffinite are the main primary minerals, while uranophane and kasolite are the secondary ones. Galena, chalcopyrite, pyrrohtite and pyrite are the most abundant sulphides in association with uranium mineralizations. Hydrothermal alterations at the GII occurrence exhibit an increase in Ni, Cu, Zn, Pb, Mo, Nb, Rb beside HREEs and a decrease in Ba, Co, Sr, and V, while alterations at the GV occurrence show enrichment in Ni, Cu, Pb, Mo, Nb, Y, HREEs and depletion in Zn, Ba, Co, Rb, Sr, and V. Hydrothermal alteration during the late magmatic stage is also identified through the development of unusual REE patterns and fractionation of ratios like Zr/Hf and Y/Ho out of the CHARAC (Charge Radius Con-trolled) range. Non-chondritic Y/Ho ratio at GV is of larger value than chondritic one which may result from wa-ter-rock interaction or print from the encompassing sedimentary rocks. Fluid inclusion studies on quartz and fluorite revealed that temperatures of the mineralizing fluids range between 126 and 240℃ at pressure ≤0.5×108 Pa and give salinity values ranging between 1 wt% and 7.8 wt% NaCl equivalent.El-Feky M.G. 2011Chinese Journal Of Geochemistry2011,30,4:5
9SIMULATION OF THE MICROSTRUCTURE DISTRIBUTION OF HYDROGEN STORAGE ALLOY AND OPTIMAL DESIGN OF CASTING MOULDS显示文摘In this paper,a simulation model for the temperature field in the solidification process and microstructure distribution is presented. Then, the result of simulation for the final microstructure distribution is compared with experiment using 10-Kg ingot of MlNi3.55Al0.3Mn0.4CO0.75 (Ml: Lanthanum-rich Mischmetal) hydrogen stor- age alloy cast in a mould, which agrees with the experiment well. Finally, in order to obtain the expected as-cast microstructure distribution of 15-Kg ingot of MlNi3.55Al0.3Mn0.4Co0.75 alloy, the size of Cu mould is optimized using the model described. The optimized mould is then made and the alloy is cast in it, the expected as-cast microstructure distribution is obtained.Q.A. Li, H.Q. Mo, Y.Z. Huo, G. Sang, Y.F. Chen, M.G. Han, Y.G. Chen and M.J. Tu Department of Metal Materials, Sichuan University, Chengdu 610065, China 2000Acta Metallurgica Sinica(English Letters)2000,13,2:4
10妊娠期及产后静脉血栓栓塞的发生率、危险因素及死亡率显示文摘Objective: The purpose of this study was to estimate the incidence,risk factors, and mortality from pregnancy-related venous thromboembolism. Study design: The Nationwide Inpatient Sample from the Healthcare Cost and Utilization Project of the Agency for Healthcare Research and Quality for the years 2000 to 2001 was queried for all pregnancy-related discharges with a diagnosis of venous thromboembolism. Results: The rate of venous thromboembolism was 1.72 per 1000 deliveries with 1.1 deaths per 100,000. The risk of venous thromboembolism was 38% higher for women ages 35 and older and 64% higher for black women. Other significant risk factors included thrombophilia, lupus, heart disease, sickle cell disease,obesity, fluid and electrolyte imbalance, postpartum infection,and transfusion. The risk factor with the highest odds ratio, 51.8(38.7- 69.2) was thrombophilia. Conclusion: The incidence of pregnancy-related venous thromboembolism was higher than generally quoted. Women ages 35 and older, black women, and women with certain medical conditions and obstetric complications appear to be at increased risk.James A.H. Jamison M.G. Brancazio L.R. Myers E.R. 李奎 2006世界核心医学期刊文摘(妇产科学分册)2006,2,9:3
11Mineralogy,M-type tetrad effect and radioactivity of altered granites at the G.Abu Garadi shear zone,central Eastern Desert,Egypt显示文摘The G. Abu Garadi area is covered mainly by metasediments, alkali feldspar granites and stream sediments. The alkali feldspar granite is traversed by a major strike-slip fault trending in an N-S direction as well as two subordinate sets of faults trending NW to WNW for the first one and NE for the second one. These faults represent the shear zones affected by magmatic (syngenetic) as well as hydrothermal (epigenetic) activities causing alteration of the granitic rocks. The most common alteration features are albitization, greisenization and koalinitization. The mass balance calculations of the studied altered samples show enrichments in Zr, Y, Ni, U, Th and Ga and depletions in Zn, Sr, Nb, Ba, Pb, Cu and V. Only the greisenized samples exhibit a significant enrichment in Nb, ∑REE budget and pronounced lanthanide tetrad effect (M-type), especially TE1,4, while weakly expressed tetrad effects are for the other albitized and koalinitized samples. Mineralogically, the common accessory minerals in the altered samples include samarskite-(Y), betafite, uranothorite, zircon, fluorite and cassiterite. The greisenized granites contain high eU and eTh than the other altered types, where they are characterized by an assemblage of the radioactive minerals; samarskite-(Y), betafite, uranothorite in addition to zircon. The inter-element relationships between U and Th and also their ratios illustrate that the radioelement distribution in these granites is mainly governed by magmatic processes, in addition to post-magmatic ones. The distribution of chemical elements and the fractionation of some isovalents within the shear zone are largely controlled by the newly formed mineral phases. With respect to uranium mobilization, uranium migrated from the host alkali feldspar granites of G. Abu Garadi, while the shear zones acted as traps for the migrated uranium. Moreover, U migrated in the shear zone during greisenization and albitization, and migrated out during koalinitization.El Nahas H.A. El Feky M.G. Mira H. 2011Chinese Journal Of Geochemistry2011,30,2:3
12ORIENTATION VARIANT SELECTION AND ITS EFFECTING FACTORS IN TITANIUM SHEET显示文摘ORIENTATIONVARIANTSELECTIONANDITSEFFECTINGFACTORSINTITANIUMSHEETZ.S.Zhu;N.P.Chen;J.L.GuandM.G.Yan(1)InstituteofAeronauticalMa...Z.S. Zhu N.P.Chen J.L. Gu and M.G. Yan(1)Institute of Aeronautical Materials, P.O. Box 8115, Beijing 100095, China 2)Department of Materials Science and Engineering, Tsinghua University, Beijing 100084, ) 1996Acta Metallurgica Sinica(English Letters)1996,9,6:2
13Ultrasound elastography as an adjuvant to conventional ultrasound in the preoperative assessment of axillary lymph nodes in suspected breast cancer: A pilot study显示文摘K. Taylor S. O’Keeffe P.D. Britton M.G. Wallis G.M. Treece J. Housden D. Parashar S. Bond R. Sinnatamby 2011Clinical Radiology2011,,11:2
14Critical and subcritical ischaemia显示文摘J.H.N. Wolfe M.G. Wyatt 1997European Journal of Vascular & Endovascular Surgery1997,,:2
15Mineralogy,geochemistry,radioactivity and environmental impacts of Gabal Marwa granites,southeastern Sinai,Egypt显示文摘The Gabal Marwa area is located in the southeastern part of Sinai,Egypt.It comprises gneisses and migmatites,granodiorites and monzogranites.Field,petrographic,mineralogic and chemical investigations indicated that the Gabal Marwa granites are classified as granodiorites and monzogranites.The monzogranites constitute the most predominant rock unit exposed in the study area.They have been subjected to hydrothermal alterations,especially along the shear zones.Sericitization,desilicification,nametasomatism and development of spotty or dendritic manganese oxides are the most pronounced alteration features.These alterations resulted in the increase of TiO2,Al2O3,FeOt,MnO,CaO,MgO,Na2O,K2O and Cr,Zr,Rb,Y and Sr and the decrease of SiO2,P2O5,Ni,Zn,Ba and Nb.Radiometric studies indicated that the altered granites belong to high thorium,high uranium granites.The U,Th,U and Th,Th/U,Th and U-K variation diagrams suggested that magmatic processes controlled the distribution of these elements but the effect of hydrothermal alteration processes were clearly distinct.The Scanning Electron Microscope and X-ray Diffraction analyses indicated that the most important radioactive minerals include uranothorite,thorite,zircon,monazite and samarskite.Cinnabar and Mn minerals were also found.From the U,Th,Ra and K activity concentrations obtained for all the studied granitic samples,radium equivalent activity(Raeq),external hazard index(Hex),and internal hazard index(Hin),were calculated to assess the radiation hazard to human beings living in dwellings made of the studied granites.Altered monzogranites have radioactivity above the proposed acceptable level and,therefore,caution must be taken when these granites are used as building materials.El Feky M.G. El Mowafy A.A. Abdel Warith A. 2011Chinese Journal Of Geochemistry2011,30,2:2
16Influence of the inlet velocity profiles on the prediction of velocity distribution inside an electrostatic precipitator显示文摘Shah M.E. Haque M.G. Rasul M.M.K. Khan A.V. Deev N. Subaschandar 2008Experimental Thermal and Fluid Science2008,,2:2
17Cyclooxygenase inhibitory and antioxidant cyanidin glycosides in cherries and berries显示文摘N.P. Seeram R.A. Momin M.G. Nair L.D. Bourquin 2001Phytomedicine2001,,5:2
18Management der postpartalen Blutung (PPH)显示文摘D. Schlembach M.G. M?rtl T. Girard W. Arzt E. Beinder C. Brezinka K. Chalubinski D. Fries W. Gogarten B.-J. Hackel?er H. Helmer W. Henrich I. H?sli P. Husslein F. Kainer U. Lang G. Pfanner W. Rath E. Schleussner H. Steiner D. Surbek R. Zimmermann 2014Der Anaesthesist2014,,3:2
19A Practical Guide for the Diagnosis of Primary Enteric Nervous System Disorders显示文摘M.G. Sch?ppi A. Staiano P.J. Milla V.V. Smith J.A. Dias R. Heuschkel S. Husby M.L. Mearin A. Papadopoulou F.M. Ruemmele Yvan Vandenplas S. Koletzko 2013Journal of Pediatric Gastroenterology and Nutrition2013,,5:2
20Time-dependent springback of advanced high strength steels显示文摘H. Lim M.G. Lee J.H. Sung J.H. Kim R.H. Wagoner 2011International Journal of Plasticity2011,,:2
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