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Effects of Heavy Metal Stress on the Growth Curves of Two Sepcies of Bacteria 被引量:4
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作者 李淑英 苏亚丽 +2 位作者 周元清 史云东 别金蓉 《Agricultural Science & Technology》 CAS 2010年第8期149-152,共4页
[Objective] The aim was to study on the effects of heavy metal stress on the growth curves of Escherichia coli and Bacillus subtili. [Method] Using traditional culture method,Escherichia coli and Bacillus subtili were... [Objective] The aim was to study on the effects of heavy metal stress on the growth curves of Escherichia coli and Bacillus subtili. [Method] Using traditional culture method,Escherichia coli and Bacillus subtili were cultured under heavy metal stress including Cu2+,Hg2+,Pb2+,Cd2+ and Cr6+ in different concentrations. Then the growth curves of the bacteria were determined to investigate the effects of exogenous heavy metals on the growth of the two kinds of bacteria. [Result] The proliferation of the two bacteria was inhibited at high concentrations of Hg2+ and Cd2+ respectively,and G+ is more sensitive to them than G-; when the heavy metal concentration was 50 mg/L,the toxicity of the five kinds of heavy metals on the two bacteria was Hg2+Cd2+Cu2+Cr6+≈Pb2+. [Conclusion] The research will provide a basis to explore the effects of heavy metal on environment and ecological system. 展开更多
关键词 Heavy metal Escherichia coli Bacillus subtili Growth curve STRESS
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奶牛乳房性状的数量化理论分析
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作者 焦骅 冯蕴华 于海东 《畜牧兽医学报》 CAS CSCD 北大核心 1989年第S1期6-11,共6页
本文对275头奶牛的26个性状进行了多元回归和数量化理论Ⅰ的分析。结果为:乳房曲长、乳井直径和乳静脉直径大小与产奶量相关极其密切,其中乳房曲长是乳房容积的代表性状。腹围与各项产奶量相关显著,可作为外貌鉴定中的重要性状。根据26... 本文对275头奶牛的26个性状进行了多元回归和数量化理论Ⅰ的分析。结果为:乳房曲长、乳井直径和乳静脉直径大小与产奶量相关极其密切,其中乳房曲长是乳房容积的代表性状。腹围与各项产奶量相关显著,可作为外貌鉴定中的重要性状。根据26个性状与305天产奶量的多元回归分析,得方程式:(?)=6567.43-169.85X_(14)-32.6X_(20)+6.8X_(24)+6.44X_(250)R值为0.66,说明该式对估计305天产奶量具有一定准确性。 展开更多
关键词 外貌鉴定 多元回归分析 曲长 数量化理论 日产奶量 表型相关 体躯 产犊 体尺 校正系数
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Callus Induction and Cell Suspension Culture of Eggplant(Solanum melongena L.) 被引量:1
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作者 王凤华 李光远 +2 位作者 陈双臣 蒋燕 王少先 《Agricultural Science & Technology》 CAS 2013年第9期1220-1223,1243,共5页
[Objective] The aim of this article is to establish a cell suspension culture system for eggplant. [Method] Using orthogonal design, appropriate media were screened for callus induction, subculture and cell suspension... [Objective] The aim of this article is to establish a cell suspension culture system for eggplant. [Method] Using orthogonal design, appropriate media were screened for callus induction, subculture and cell suspension culture. [Result] The appropriate medium for callus induction was MS supplemented with 0.2 mg/L 6-BA and 0.2 mg/L NAA; the appropriate subculture medium was MS supplemented with0.2 mg/L 6-BA, 0.2 mg/L NAA, and 0.1 mg/L KT; the suitable medium for cell suspension culture was liquid MS medium supplemented with 0.4 mg/L NAA and 0.2mg/L. Cell growth curve was similar to "S" shape in the above suspension medium.The cell growth included four phases, the initial phase(1-3 d), the logarithmic phase(3-7 d), the steady phase(7-8 d), and the decline phase(8-11 d). With the increasing culture time, the number of suspension cells increased, and it reached the maximum value at the 7thd, about 3.8 ×105cells/ml. Then the number of cells began to decline rapidly. The cell vigor was the highest at the initial phase. Suspension cells grew best in the liquid MS medium supplemented with NAA(0.4 mg/L)and 6-BA(0.2 mg/L). The mitotic index reached the maximum, about 4.1% in the above medium, which suggested that this medium was suitable for cell suspension culture of eggplant. [Conclusion] Cell suspension culture system of eggplant provides a significant method for eggplant biotechnology. Genetic transformation and mutants screening can be carried out with this system. 展开更多
关键词 EGGPLANT CALLUS Suspension culture Growth curve
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Influence of main site factors on Fraxinus mandshurica (Oleaceae) plantation 被引量:5
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作者 苏含英 林代斌 《Journal of Forestry Research》 SCIE CAS CSCD 2003年第1期83-86,共4页
the investigation was carried out on 10-year-old plantation of Fraxinus mandshurica in Mao抏r Mountain Experimental Station of Northeast Forest University. Tree height (H), diameter at breast height (D1.3) and the inc... the investigation was carried out on 10-year-old plantation of Fraxinus mandshurica in Mao抏r Mountain Experimental Station of Northeast Forest University. Tree height (H), diameter at breast height (D1.3) and the increment of tree height in 5 years (H5), the thickness of humus layer, as well as the soil moisture were measured for the plantation and the growth indexes (H, D1.3, H5) for different site conditions were analyzed. The results showed that main site factors influencing the growth of Fraxinus mandshurica were soil moisture, gradient and location of slope in order. The growth of Fraxinus mandshurica was better on the middle- or up-slope site than on the down-slope site. Soil moisture and late frost caused by terrain are the main reasons that limit the growth of Fraxinus mandshurica plantation. 展开更多
关键词 Fraxinus mandshurica PLANTATION Site factors
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Rhizome Elongation Growth of Umbrella Bamboo(Fargesia murielae) Seedlings at Its Native Home in Central China 被引量:2
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作者 王玲 李昆 +2 位作者 孟银萍 赵丽雅 李兆华 《Agricultural Science & Technology》 CAS 2012年第5期969-971,1027,共4页
[Objective] The aim was to investigate the rhizome elongation growth of umbrella bamboo (Fargesia murielae) seedlings in China. [Method] The study was conducted in Liangfengya, Shennongjia National Nature Reserve. I... [Objective] The aim was to investigate the rhizome elongation growth of umbrella bamboo (Fargesia murielae) seedlings in China. [Method] The study was conducted in Liangfengya, Shennongjia National Nature Reserve. In the field investigation, six clumps of umbrella bamboo which grow independently were randomly selected and labeled. Rhizome elongation growth parameters, length and diameter of all the ages were measured. The age classes of bamboo rhizome were ascertained by age grade backtracking method. [Result] Field investigation suggested that at seedling phase, rhizome of umbrella bamboo prolonged very quickly under yearly time sequence, following an exponential curve. It indicated that although it was 15 years since the mother population died back, new generation had not been established its stable population yet. [Conclusion] Studying elongation regulation of umbrella bamboo may provide the theory understanding of life cycle of this long lived bamboo species. 展开更多
关键词 Fargesia murielae Cloning growth Bamboo rhizome Curve fitting Shennongjia
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Variation Law of Pericarp Tenderness of Super Sweet Corn Kernel
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作者 张士龙 黄益勤 +1 位作者 贺正华 李小琴 《Agricultural Science & Technology》 CAS 2016年第7期1671-1674,共4页
To investigate the variation law of pericarp tenderness in growth progress of super sweet corn kernel, the values of pericarp tenderness of 10 super sweet corn inbreeds were measured during kernel growth, and the vari... To investigate the variation law of pericarp tenderness in growth progress of super sweet corn kernel, the values of pericarp tenderness of 10 super sweet corn inbreeds were measured during kernel growth, and the variations under differ- ent conditions were analyzed. The results showed that there existed gradient differ- ences in pericarp tenderness among the 10 materials, of which PE10 had the best pericarp tenderness, T105 took medial place, and $33205 performed worst in peri- carp tenderness. Pericarp tenderness values of these 3 inbreeds increased curvedly from 12 to 24 days after pollination, in the spring (Wuhan, Hubei) and winter (Ling- shui, Hainan) of 2014. Moreover, the average pericarp tenderness at different time points presented the same decreasing order of $33205, T105, PE10, which was not altered by enviroment. With the growth of kernel, for one material, the difference of pericarp tenderness under different environments presented a law of increment, re- duction, uniformity. As for optimum-picking time, there was four days difference be- tween the spring in Wuhan and winter in Lingshui. However, there was no obvious difference in pericarp tenderness on the optimum picking time, which indicated that growing environment could affect the variation ratio of pericarp tenderness, but it still depended on the nature of materials. 展开更多
关键词 Super sweet corn Pericarp tenderness Variation law Growth curve
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一个养殖林蛙的专业村
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作者 李继昌 《北方园艺》 CAS 北大核心 1989年第10期45-45,共1页
辽宁省清原县北三家满族乡李家堡村,山多林密,沟谷纵横,溪流密布,水资源丰富。1985年春,清原县农业区划办公室在该村选点,进行人工围拦养殖中国林蛙试验。这个村农民曲长青、郭德诚,唐纯,在有关部门的帮助和扶持下,担负起了试验任务。这... 辽宁省清原县北三家满族乡李家堡村,山多林密,沟谷纵横,溪流密布,水资源丰富。1985年春,清原县农业区划办公室在该村选点,进行人工围拦养殖中国林蛙试验。这个村农民曲长青、郭德诚,唐纯,在有关部门的帮助和扶持下,担负起了试验任务。这3户农民,先在养殖场内修建了一个越冬池和孵化池,然后收集卵团,放入孵化池。 展开更多
关键词 围拦养殖 清原县 区划办公室 孵化池 越冬池 中国林蛙 李家堡 北三 曲长 试验任务
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Study on Growth and Development Rules and Growth Curve Fitting of Minghua Black Minks
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作者 荣敏 涂剑锋 +3 位作者 张志明 王淑茗 高峰 邢秀梅 《Agricultural Science & Technology》 CAS 2017年第2期285-286,302,共3页
Growth curves of Minghua black minks at 0-180 days old were fitted and analyzed by using two growth models Logistic and Gompertz. The results showed that the growth curves of Minghua black minks could be fitted very w... Growth curves of Minghua black minks at 0-180 days old were fitted and analyzed by using two growth models Logistic and Gompertz. The results showed that the growth curves of Minghua black minks could be fitted very well by Logistic model and Gompertz model (the degree of fitting FF≥0.99), but Gompertz model was better at fitting and predicting their weight. 展开更多
关键词 Minghua black minks Growth curve Non-lineared models Development rules FITTING
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品树
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作者 管用和 《财政与发展》 北大核心 2002年第21期45-45,共1页
高楼与高楼之间的空地上,生长着高高低低为数不多的树木。高的娉婷,修长秀逸挺然而立的是水杉,那昂然直上的身杆,呈英武之姿,稳扎地撑起勃勃生机。矮的端庄,绿叶蓬生苍翠欲滴是桂树,那枝杈错综云团般的体形,显潇洒之态,活鲜鲜地造就一... 高楼与高楼之间的空地上,生长着高高低低为数不多的树木。高的娉婷,修长秀逸挺然而立的是水杉,那昂然直上的身杆,呈英武之姿,稳扎地撑起勃勃生机。矮的端庄,绿叶蓬生苍翠欲滴是桂树,那枝杈错综云团般的体形,显潇洒之态,活鲜鲜地造就一片葱茏蓊郁。还有白杨、女贞、棕榈、冬青、木芙蓉和一些不知名的树,都各有姿态。有的密集,有的疏朗,有的繁琐,有的简洁,有的细柔,有的则刚曲。这些树也各具神情,有的放达,有的俊逸,有的倔强, 展开更多
关键词 桂树 于斯 怡情 之乐 氤氤氲氲 咖啡屋 随风飘荡 曲长 清响 叶飞
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Effects of Pb on Growth and Development of Broad Bean Roots
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作者 张燕 《Agricultural Science & Technology》 CAS 2013年第4期595-597,共3页
[Objective] This study aimed to investigate the influence of Pb2+ on the growth and development of broad bean roots. [Method] The effects of Pb2+ solution of different concentrations on root length, color, bending a... [Objective] This study aimed to investigate the influence of Pb2+ on the growth and development of broad bean roots. [Method] The effects of Pb2+ solution of different concentrations on root length, color, bending and mitotic index frequency of root tip cells of broad bean were measured and observed. [Result] Pb2+ at concentration lower than 20 mg/L promoted the growth and development of roots, increased the cell mitotic indexes, but had little influence on root color and bending. When the Pb2+ concentration was higher than 20 mg/L, the root growth was inhibited; the root color gradually turned deeper; the roots bended, but the cell mitotic index was decreased. [Conclusion] Pb2+ promoted the growth of broad bean at low concentration but inhibited the growth at high concentration, and the influence was related to Pb2+ concentration and time. 展开更多
关键词 Pb2+ Broad bean Root length BENDING COLOR MITOSIS
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红旗下的思念
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作者 王盛昌 李和平 《黄河之声》 1994年第2期6-7,共2页
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关键词 二目 赵越 曲长 子传 三厂 路光 水导 一三 人天 王三
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壶口瀑布
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作者 温祥 《沧桑》 1993年第1期49-49,共1页
(一) 奔腾咆哮自遥空, 百丈金帘卷大风。虚壑为怀雷作胆, 中华魂激浪千重。 (二) 飞流触地地生烟, 怒水扬声声震天。多少英豪餐母乳, 头颅敢抽国门悬。 (三) 许是河神弹竖琴, 无弦韵远响天音。龙吟虎啸难相比, 一曲长凝万众心。
关键词 声震 曲长 少英
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幼龄苹果园间作花生栽培模式
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作者 张国林 《河北果树》 1993年第3期10-11,共2页
近年,在阳原县新发展苹果2万余亩,其中曲长城材在1500亩幼龄苹果园中间作花生,取得了较好的生态效益.实践证明,幼龄苹果园间作花生是丘陵地区一种高效益的栽培模式.
关键词 花生栽培 苹果属 苹果幼树 阳原县 生态效益 曲长 春季修剪 花生植株 新梢 栽培模式
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来函照登
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作者 曾宪堡 《小学教学研究》 1992年第11期34-34,共1页
编辑同志: 您好! 拜读了《小学教学研究》1992年第四期的《巧用分解质因数解题》一文,深受启发。但笔者认为文中“(六)用分解质因数解几何题”
关键词 分解质因数 小学教学研究 文中 平方分米 立方分米 曲长 棱长 三条
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张选亮:让荒滩变为生态园
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作者 刘菱 《农家致富》 2016年第24期57-57,共1页
江苏省常州市溧阳西部,宁杭高速上兴道口,总面积380多亩的上兴瑶东农业生态园,以其集农业、民宿、餐饮、水产与垂钓于一体的农旅融合经营格局,吸引了众多游客。走进瑶东农业生态园,成片的水稻在凉爽秋风吹拂下,泛起金色稻浪。
关键词 农业生态园 曲长 宁杭高速 江苏省常州市 农产品销售 接待中心 投资潜力 营销主管 岸堤 营销经验
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构建垦区水利行业经营服务体系的基本思路
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作者 曲长地 孙景先 《农场经济管理》 1994年第6期60-61,共2页
构建垦区水利行业经营服务体系的基本思路曲长地,孙景先一水二路三开荒四造林”是黑龙江垦区发展历史的经验总结。突出了水利在垦区经济发展中的地位。积四十年水利建设,国家设资的垦区自筹累计达数十亿元,建成一批防洪、除涝、灌溉... 构建垦区水利行业经营服务体系的基本思路曲长地,孙景先一水二路三开荒四造林”是黑龙江垦区发展历史的经验总结。突出了水利在垦区经济发展中的地位。积四十年水利建设,国家设资的垦区自筹累计达数十亿元,建成一批防洪、除涝、灌溉、水土保持、小水电、人畜饮水等项工... 展开更多
关键词 水利行业 经营服务 垦区经济 人畜饮水 水利建设 曲长 经验总结 水利事业 勘测设计 基础产业
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Determination of Lycopene Concentration in Dog Plasma by RP-HPLC
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作者 王会娟 李馨儒 +1 位作者 黄燕清 刘艳 《Journal of Chinese Pharmaceutical Sciences》 CAS 2004年第4期259-261,共3页
A method for determination of lycopene concentration in dog plasma wasestablished. Methods RP-HPLC was used; the mobile phase consisted of methanol-acetonitrile-methylenechloride (40:30:30, V/V) , the wavelength of de... A method for determination of lycopene concentration in dog plasma wasestablished. Methods RP-HPLC was used; the mobile phase consisted of methanol-acetonitrile-methylenechloride (40:30:30, V/V) , the wavelength of detection was 472 nm, the column temperature wasambient temperature, and the flow rate was 1.0 mL·min^(-1). Results The standard curve was linearin the range from 0.012 4 to 0.496 μg·mL^(-1) with r=0.9992. The average extraction recovery was97.6% +-4.2%. The intra-day and inter-day RSD were 1.52% -4.95% and 2.31% -7.38%, respectively.Conclusion This method is sensitive, rapid, reproducible, and of good selectivity for the analysisof lycopene in dog plasma. 展开更多
关键词 LYCOPENE plasma concentration RP-HPLC
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Optimized nonhyperbolic moveout correction equation of long-offset seismic data for TI media with an arbitrary spatial orientation
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作者 郝重涛 姚陈 张建中 《Applied Geophysics》 SCIE CSCD 2010年第4期336-347,400,共13页
The conventional long-offset nonhyperbolic moveout equation is derived for the transverse isotropic media with a vertical symmetric axis(VTI).It cannot be extended to the transverse isotropic media with an arbitrary... The conventional long-offset nonhyperbolic moveout equation is derived for the transverse isotropic media with a vertical symmetric axis(VTI).It cannot be extended to the transverse isotropic media with an arbitrary spatial orientation of symmetry axis(ATI).In this paper,we optimize a modified long-offset nonhyperbolic moveout equation for ATI media based on the conventional nonhyperbolic moveout equation and the exact analytical solution of the quartic moveout coefficient(A_4) and NMO velocity for ATI media that were derived in our previous work.Compared with the exact traveltimes of the ray-tracing algorithm for anisotropic media,this optimized equation can be used to calculate the traveltime varying with survey line azimuth in arbitrary strong or weak ATI media.It can replace the time-consuming, multi-offset,and multi-azimuth ray tracing method for forward modeling of long-offset reflection traveltimes in ATI media,which is useful to further anisotropic parameter inversion using long-offset nonhyperbolic moveout. 展开更多
关键词 TI media arbitrary spatial orientation nonhyperbolic moveout equation reflection traveltime long-offset
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Stochastic simulation of growth curves of Acidithiobacillus ferrooxidans 被引量:1
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作者 杨宇 彭宏 +2 位作者 邱冠周 柳建设 胡岳华 《Journal of Central South University of Technology》 EI 2006年第5期473-476,共4页
To reveal the low growth rate of Acidithiobacillus ferrooxidans, a stochastic growth model was proposed to analyze growth curves of these bacteria in a batch culture. An algorithm was applied to simulate the bacteria ... To reveal the low growth rate of Acidithiobacillus ferrooxidans, a stochastic growth model was proposed to analyze growth curves of these bacteria in a batch culture. An algorithm was applied to simulate the bacteria population during lag and exponential phase. The results show that the model moderately fits the experimental data. Further, the mean growth constant (K) of growth curves is obtained by fitting the logarithm of the simulating population data versus the generation numbers with the different initial population number (N0) and initial mean activity of population (A0). When No is 300 and 700 respectively, the discrepancy of K value is only 0.91%, however, A0 is 0.34 and 0.38 respectively, the discrepancy of K value is 19.53%. It suggests that the effect of A0 on the lag phase exceeds No, though both parameters could shorten the lag phase by increasing their values. 展开更多
关键词 Acidithiobacillus ferrooxidans stochastic simulation growth curves lag phase
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Buckling analysis of super-long rock-socketed filling piles in soft soil area by element free Galerkin method 被引量:2
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作者 邹新军 赵明华 刘光栋 《Journal of Central South University of Technology》 EI 2007年第6期858-863,共6页
In order to discuss the buckling stability of super-long rock-socketed filling piles widely used in bridge engineering in soft soil area such as Dongting Lake, the second stability type was adopted instead of traditio... In order to discuss the buckling stability of super-long rock-socketed filling piles widely used in bridge engineering in soft soil area such as Dongting Lake, the second stability type was adopted instead of traditional first type, and a newly invented numerical analysis method, i.e. the element-free Galerkin method (EFGM), was introduced to consider the non-concordant deformation and nonlinearity of the pile-soil interface. Then, based on the nonlinear elastic-ideal plastic pile-soil interface model, a nonlinear iterative algorithm was given to analyze the pile-soil interaction, and a program for buckling analysis of piles by the EFGM (PBAP-EFGM) and arc length method was worked out as well. The application results in an engineering example show that, the shape of pile top load-settlement curve obtained by the program agrees well with the measured one, of which the difference may be caused mainly by those uncertain factors such as possible initial defects of pile shaft and the eccentric loading during the test process. However, the calculated critical load is very close with the measured ultimate load of the test pile, and the corresponding relative error is only 5.6%, far better than the calculated values by linear and nonlinear incremental buckling analysis (with a greater relative error of 37.0% and 15.4% respectively), which also verifies the rationality and feasibility of the present method. 展开更多
关键词 super-long rock-socketed filling pile buckling analysis element free Galerkin method critical load
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