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BCI-代数与其商代数的理想集或子代数集之间的对应关系
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作者 朱怡权 《内江师范学院学报》 1989年第S2期73-73,共1页
以p表BCI-代数X到其商代数X/N的典则映射,C.记X/N的常元;P表由p导出的从X的益集到X/N的幂集的映射;对X的任一非空子集M,以ID(X,M),SA(X,M),IS(X,M)分别表示X中一切包含M的理想、子代数、理想子代数的集,当M={0}时,这些记号分别简写为ID(... 以p表BCI-代数X到其商代数X/N的典则映射,C.记X/N的常元;P表由p导出的从X的益集到X/N的幂集的映射;对X的任一非空子集M,以ID(X,M),SA(X,M),IS(X,M)分别表示X中一切包含M的理想、子代数、理想子代数的集,当M={0}时,这些记号分别简写为ID(X),SA(X),IS(X).关于BCI-代数与其商代数的理想集或子代数集之间的对应关系,有下列结果: 展开更多
关键词 商代数 BCI 子代数 代数集 当且仅当 常元 幂集 满射 双射
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Fuzzy BCK—代数
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作者 黄万徽 《应用数学》 CSCD 北大核心 1990年第1期98-99,共2页
在集合论中关于差的运算及在命题演算中关于→的运算均具有以下性质: 1) (x*y)*(x*z)≤(z*y); 2) x*(x*y)≤y; 3) x≤x, 4) 0≤x; 5) 若x≤y,y≤x则x=y; 6) x≤y x*y=0. 在集合论中,“*”表示两个集合之差的运算,“≤”表示两个集合之... 在集合论中关于差的运算及在命题演算中关于→的运算均具有以下性质: 1) (x*y)*(x*z)≤(z*y); 2) x*(x*y)≤y; 3) x≤x, 4) 0≤x; 5) 若x≤y,y≤x则x=y; 6) x≤y x*y=0. 在集合论中,“*”表示两个集合之差的运算,“≤”表示两个集合之间的包含“(?)”关系,“0”表示空集,“=”表示两个集合相等.在命题演算中,“*” 展开更多
关键词 FUZZY BCK-代数 二元运算 常元
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Study on the Major and Trace Elements in Soil of Yunnan Farmland
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作者 徐娟 刘刚 +3 位作者 赵兴祥 赵帅群 任静 胡建飞 《Agricultural Science & Technology》 CAS 2014年第12期2141-2144,共4页
In order to investigate the distribution of soil available micronutrients, and provide a theoretical basis for management of fertilizing reasonably on crops, the contents of major and trace elements (P, K, Ca, Mg, Cu... In order to investigate the distribution of soil available micronutrients, and provide a theoretical basis for management of fertilizing reasonably on crops, the contents of major and trace elements (P, K, Ca, Mg, Cu, Fe, Zn, and Mn) in farm- land soil collected from Yunnan Province were determined by inductively coupled plasma-mass spectrometry (ICP-MS), the contents and distribution of major and trace elements were also studied. The results showed that the contents of available P, K were balance, available Ca, Mg were deficient, and available Cu, Fe, Zn, Mn were very plentiful. Major and trace elements distribution of different landform areas were obviously different. The contents of trace elements (Fe, Zn and Mn) of central Yunnan Red Plateau were significantly higher than those of Hengduan Mountains in western Yunnan and those of karst plateau in eastern Yunnan. The contents of available P, K, and Ca gradually declined from west to east, while the content of available Cu rose gradually from west to east. The results are reference value to elements determination and agricultural production in farmland soils. 展开更多
关键词 ICP-MS Soil of Yunnan farmland Major elements Trace elements CONTENT
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逻辑性和弗雷格算术与简单类型论的逻辑主义
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作者 石伟军 《逻辑学研究》 CSSCI 2020年第3期62-81,共20页
弗雷格和罗素的逻辑主义由两个部分构成:可证明性论题和可定义性论题。可以很确信地说,可证明性论题并不能得到完全的辩护。但是,为了向两者,特别是可定义性论题,提供辩护或者拒斥之,我们需要逻辑性的标准来决定,除了其它常元的逻辑性之... 弗雷格和罗素的逻辑主义由两个部分构成:可证明性论题和可定义性论题。可以很确信地说,可证明性论题并不能得到完全的辩护。但是,为了向两者,特别是可定义性论题,提供辩护或者拒斥之,我们需要逻辑性的标准来决定,除了其它常元的逻辑性之外,表示数的常元和表示属于关系的常元的逻辑性。我将采用的逻辑性标准是塔尔斯基和谢尔提出的同构不变量标准和费弗曼提出的同态不变量标准。塔尔斯基和谢尔在不同的地方已经指出罗素的表示属于关系的常元是同构不变量。在本文中,我将证明如下结论:第一,表示属于关系的常元是同态不变量;第二,弗雷格的表示数的常元既不是同构不变量也不是同态不变量;第三,如果逻辑性是同构不变量或者同态不变量,弗雷格的逻辑主义(弗雷格算术)的可定义性论题不成立;第四,如果逻辑性是同构不变量,罗素的逻辑主义(简单类型论)的可定义论题成立,但若逻辑性是同态不变量,这个论题则不成立。 展开更多
关键词 逻辑主义 弗雷格 常元 同态 可定义性 塔尔斯基 同构 谢尔
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“统一思想“的领导功能及实现艺术
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作者 李一 李新 《领导科学》 1987年第12期24-26,共3页
所谓“统一思想”,就是领导者在实施领导的过程中减少各种分歧看法,从思想的高度实现意见的归一化。一、“统一思想”具有一种不可忽视的领导功能我们说“统一思想”是一个不可忽视的领导功能,不仅仅是因为它经常被疏忽,还因为它是任何... 所谓“统一思想”,就是领导者在实施领导的过程中减少各种分歧看法,从思想的高度实现意见的归一化。一、“统一思想”具有一种不可忽视的领导功能我们说“统一思想”是一个不可忽视的领导功能,不仅仅是因为它经常被疏忽,还因为它是任何领导过程中的唯一贯穿始终的单位元素。我们知道,领导过程可以分解为计划决策、组织指挥、贯彻执行、督促检查和反馈调整诸环节,这些环节又各自包含着若干因素。如果这些因素成为不可再细分的元素时,我们就称它们为领导工作中的单位元素,简称单元。这样。 展开更多
关键词 领导过程 领导工作 反馈调整 领导行为 领导效能 领导意图 目标分解 检查和 常元 一条线
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赴联邦德国考察职业技术教育
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《全球科技经济瞭望》 1986年第9期37-38,共2页
由水电部黄河水利学校周文哲、唐成武,水电部教育司杨常元、文芝兰、王国权等6人组成的考察团,于1985年10月25日至11月28日在联邦德国考察了职业技术教育问题。期间,考察团走访了下萨克森州、汉堡、济根。
关键词 职业技术教育 下萨克森 黄河水利 成武 常元 汽车制造厂 教育研究所 日至 文哲 斯图加特
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3D laterolog array sonde design and response simulation 被引量:4
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作者 尹成芳 柯式镇 +3 位作者 许巍 姜明 张雷洁 陶婕 《Applied Geophysics》 SCIE CSCD 2014年第2期223-234,254,255,共14页
A new three-dimensional laterolog array sonde(3D-LS) is presented. The 3DLS is based on existing high-resolution laterolog array and azimuthal resistivity imaging sondes with radial, longitudinal, and circumferentia... A new three-dimensional laterolog array sonde(3D-LS) is presented. The 3DLS is based on existing high-resolution laterolog array and azimuthal resistivity imaging sondes with radial, longitudinal, and circumferential detection abilities. Six investigation modes are designed using the 3D finite-element method and different investigation depths are simulated based on the pseudo-geometrical factor of the six modes. The invasion profile is described using multi-array radial logs. From the analysis of the pseudo-geometrical factor, the investigation depth of the 3D-LS is about 1.5 m for conductive invasion, which is close to that of the dual laterolog tool but greater than that of the highly integrated azimuthal laterolog sonde. The vertical and azimuthal resolution is also analyzed with the same method. The 3DLS can detect low-resistivity anomalies of 0.5 m thickness and 15? around the borehole for infinitely thick formations. This study lays the foundation for more work on 3D laterolog array sonde for evaluating low-resistivity anomalies. 展开更多
关键词 Three-dimensional laterolog sonde numerical modeling FEM DETECTIVITY lowresistivity
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Exceptional family of elements and the solvability of complementarity problems in uniformly smooth and uniformly convex Banach spaces 被引量:3
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作者 ISACG. LIJin-lu 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2005年第4期289-295,共7页
The notion of “exceptional family of elements (EFE)” plays a very important role in solving complementarity prob- lems. It has been applied in finite dimensional spaces and Hilbert spaces by many authors. In this pa... The notion of “exceptional family of elements (EFE)” plays a very important role in solving complementarity prob- lems. It has been applied in finite dimensional spaces and Hilbert spaces by many authors. In this paper, by using the generalized projection defined by Alber, we extend this notion from Hilbert spaces to uniformly smooth and uniformly convex Banach spaces, and apply this extension to the study of nonlinear complementarity problems in Banach spaces. 展开更多
关键词 Exceptional family of elements (EFE) Banach spaces and complementarity
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Annual and Monthly Variations in Litter Macronutrients of Three Subalpine Forests in Western China 被引量:49
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作者 YANG Wan-Qin WANG Kai-Yun +1 位作者 S. KELLOMAKI ZHANG Jian 《Pedosphere》 SCIE CAS CSCD 2006年第6期788-798,共11页
Macronutrients (N, P, K, Ca, Mg, and S) in litter of three primarily spruce (Picea purpurea Masters) (SF), fir (Abies faxoniana Rehder & E. H. Wilson) (FF), and birch (Betula platyphylla Sukaczev) (BF) ... Macronutrients (N, P, K, Ca, Mg, and S) in litter of three primarily spruce (Picea purpurea Masters) (SF), fir (Abies faxoniana Rehder & E. H. Wilson) (FF), and birch (Betula platyphylla Sukaczev) (BF) subalpine forests in western China were measured to understand the monthly variations in litter nutrient concentrations and annual and monthly nutrient returns via litteffall. Nutrient concentration in litter showed the rank order of Ca 〉 N 〉 Mg 〉 K 〉 S 〉 P. Monthly variations in nutrient concentrations were greater in leaf litter (LL) than other litter components. The highest and lowest concentrations of N, P, K, and S in LL were found in the growing season and the nongrowing season, respectively, but Ca and Mg were the opposite. Nutrient returns via litterfall showed a marked monthly pattern with a major peak in October and one or two small peaks in February and/or May, varying with the element and stand type, but no marked monthly variations in nutrient returns via woody litter, reproductive litter, except in May for the BF, and moss litter. Not only litter production but also nutrient concentration controlled the annual nutrient return and the monthly nutrient return pattern. The monthly patterns of the nutrient concentration and return were of ecological importance for nutrient cycling and plant growth in the subalpine forest ecosystems. 展开更多
关键词 LITTERFALL macronutrient return monthly variation nutrient concentration subalpine forest
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Decomposition patterns of leaf litter of seven common canopy species in a subtropical forest: dynamics of mineral nutrients 被引量:12
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作者 XU Xiao-niu Hideaki SHIBATA Tsutomu ENOKI 《Journal of Forestry Research》 SCIE CAS CSCD 2006年第1期1-6,共6页
Dynamical patterns of mineral elements during decomposition processes were investigated for seven common canopy species in a subtropical evergreen broad-leaved forest by means of litterbag technique over 2 years. The ... Dynamical patterns of mineral elements during decomposition processes were investigated for seven common canopy species in a subtropical evergreen broad-leaved forest by means of litterbag technique over 2 years. The species studied are representative for the vegetation in the study area and differed significantly in chemical qualities of their litter. No significant relationships were found between decomposition rate (percentage dry mass remaining and decomposition constant k) and initial element cuncentrations.However, there were significant correlations betweeu the percentage of dry mass remaining and the mineral element concentrations in the remaining litter for most cases. The rank of the element mobility in decomposition process was as follows: Na = K 〉 Mg ≥ Ca 〉 N ≥ Mn ≥ Zn ≥ P 〉 Cu 〉〉 Al 〉〉 Fe. Concentrations of K and Na decreased in all species as decomposition proceeded. Calcium and Mg also decreased in concentrntion but with a temporal increase in the initial phase of decomposition, while the concentrations of other elements (Zn, Cu, AL and Fei increased for all species with exception of Mn which revealed a different pattern in different species. In most species, microelements (Cu, Al, and Fe) significantly increased in absolute amounts at the end of the litterbag incubation, which could be ascribed to a lange extent to the mechanism of abiotic fixation to humic substances rather than biological immobilization. 展开更多
关键词 Canopy species Element release Litter decomposition Litterbag experiment Microelement Evergreen broad-leaved forest
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Numerical Investigation of Transmission of Low Frequency Sound Through a Smooth Air-water Interface 被引量:3
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作者 Parviz Ghadimi Ahreza Bolghasi +1 位作者 Mohammad A. Feizi Chekab Rahim Zamanian 《Journal of Marine Science and Application》 CSCD 2015年第3期334-342,共9页
It is the traditional belief that sound transmission from water to the air is very weak due to a large contrast between air and water impedances. Recently, the enhanced sound transmission and anomalous transparency of... It is the traditional belief that sound transmission from water to the air is very weak due to a large contrast between air and water impedances. Recently, the enhanced sound transmission and anomalous transparency of air-water interface have been introduced. Anomalous transparency of air-water interface states that the sound generated by a submerged shallow depth monopole point source localized at depths less than 1/10 sound wavelength, can be transmitted into the air with omni-directional pattern. The generated sound has 35 times higher power compared to the classical ray theory prediction. In this paper, sound transmission through air-water interface for a localized underwater shallow depth source is examined. To accomplish this, two-phase coupled Helmholtz wave equations in two-phase media of air-water are solved by the commercial finite element based COMSOL Multiphysics software. Ratios of pressure amplitudes of different sound sources in two different underwater and air coordinates are computed and analyzed against non-dimensional ratio of the source depth (D) to the sound wavelength (λ). The obtained results are compared with the experimental data and good agreement is displayed. 展开更多
关键词 enhanced sound transmission anomalous transparency air-water interface shallow depth source sound transmission Helmholtz wave equations
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Different techniques for harvesting grafts for living donor liver transplantation: A systematic review and meta-analysis 被引量:6
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作者 Hui Li Jun-Bin Zhang +8 位作者 Xiao-Long Chen Lei Fan Li Wang Shi-Hui Li Qiao-Lan Zheng Xiao-Ming Wang Yang Yang Gui-Hua Chen Gen-Shu Wang 《World Journal of Gastroenterology》 SCIE CAS 2017年第20期3730-3743,共14页
AIM To perform a systematic review and meta-analysis on minimally vs conventional invasive techniques for harvesting grafts for living donor liver transplantation. METHODS PubMed, Web of Science, EMBASE, and the Cochr... AIM To perform a systematic review and meta-analysis on minimally vs conventional invasive techniques for harvesting grafts for living donor liver transplantation. METHODS PubMed, Web of Science, EMBASE, and the Cochrane Library were searched comprehensively for studies comparing MILDH with conventional living donor hepatectomy (CLDH). Intraoperative and postoperative outcomes (operative time, estimated blood loss, postoperative liver function, length of hospital stay, analgesia use, complications, and survival rate) were analyzed in donors and recipients. Articles were included if they: (1) compared the outcomes of MILDH and CLDH; and (2) reported at least some of the above outcomes. RESULTS Of 937 articles identified, 13, containing 1592 patients, met our inclusion criteria and were included in the meta-analysis. For donors, operative time [weighted mean difference (WMD) = 20.68, 95% CI: -6.25-47.60, p = 0.13] and blood loss (WMD = -32.61, 95% CI: -80.44-5.21, p = 0.18) were comparable in the two groups. In contrast, analgesia use (WMD = -7.79, 95% CI: -14.06-1.87, p = 0.01), postoperative complications [odds ratio (OR) = 0.62, 95% CI: 0.44-0.89, p = 0.009], and length of hospital stay (WMD): -1.25, 95% CI: -2.35-0.14, p = 0.03) significantly favored MILDH. No differences were observed in recipient outcomes, including postoperative complications (OR = 0.93, 95% CI: 0.66-1.31, p = 0.68) and survival rate (hr = 0.96, 95% CI: 0.27-3.47, p = 0.95). Funnel plot and statistical methods showed a low probability of publication bias. CONCLUSION MILDH is safe, effective, and feasible for living donor liver resection with fewer donor postoperative complications, reduced length of hospital stay and analgesia requirement than CLDH. 展开更多
关键词 Living donor hepatectomy Graft harvesting Minimally invasive techniques Conventional invasive approaches META-ANALYSIS
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Laparoscopic VS open hepatectomy for hepatolithiasis: An updated systematic review and meta-analysis 被引量:42
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作者 Hui Li Jun Zheng +6 位作者 Jian-Ye Cai Shi-Hui Li Jun-Bin Zhang Xiao-Ming Wang Gui-Hua Chen Yang Yang Gen-Shu Wang 《World Journal of Gastroenterology》 SCIE CAS 2017年第43期7791-7806,共16页
AIM To perform a meta-analysis on laparoscopic hepatectomy VS conventional liver resection for treating hepatolithiasis.METHODS We conducted a systematic literature search on Pub Med,Embase,Web of Science and Cochrane... AIM To perform a meta-analysis on laparoscopic hepatectomy VS conventional liver resection for treating hepatolithiasis.METHODS We conducted a systematic literature search on Pub Med,Embase,Web of Science and Cochrane Library,and undertook a meta-analysis to compare the efficacy and safety of laparoscopic hepatectomy V S conventional open liver resection for local hepatolithiasis in the left or right lobe. Intraoperative and postoperative outcomes(time,estimated blood loss,blood transfusion rate,postoperative intestinal function recovery time,length of hospital stay,postoperative complication rate,initial residual stone,final residual stone and stone recurrence) were analyzed systematically.RESULTS A comprehensive literature search retrieved 16 publications with a total of 1329 cases. Meta-analysis of these studies showed that the laparoscopic approach for hepatolithiasis was associated with significantly less intraoperative estimated blood loss [weighted mean difference(WMD): 61.56,95% confidence interval(CI): 14.91-108.20,P = 0.01],lower blood transfusion rate [odds ratio(OR): 0.41,95%CI: 0.22-0.79,P = 0.008],shorter intestinal function recovery time(WMD: 0.98,95%CI: 0.47-1.48,P = 0.01),lower total postoperative complication rate(OR: 0.52,95%CI: 0.39-0.70,P < 0.0001) and shorter stay in hospital(WMD: 3.32,95%CI: 2.32-4.32,P < 0.00001). In addition,our results showed no significant differences between the two groups in operative time(WMD: 21.49,95%CI: 0.27-43.24,P = 0.05),residual stones(OR: 0.79,95%CI: 0.50-1.25,P = 0.31) and stone recurrence(OR: 0.34,95%CI: 0.11-1.08,P = 0.07). Furthermore,with subgroups analysis,our results proved that the laparoscopic approach for hepatolithiasis in the left lateral lobe and left side could achieve satisfactory therapeutic effects. CONCLUSION The laparoscopic approach is safe and effective,with less intraoperative estimated blood loss,fewer postoperative complications,reduced length of hospital stay and shorter intestinal function recovery time than with conventional approaches. 展开更多
关键词 HEPATOLITHIASIS Laparoscopic hepatectomy Conventional liver resection Systematic review Metaanalysis
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Trace metal anomalies in bleached Porites coral at Meiji Reef, tropical South China Sea 被引量:3
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作者 LI Shu YU Kefu +2 位作者 ZHAO Jianxin FENG Yuexing CHEN Tianran 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2017年第1期115-121,共7页
Coral bleaching has generally been recognized as the main reason for tropical coral reef degradation, but there are few long-term records of coral bleaching events. In this study, trace metals including chromium(Cr), ... Coral bleaching has generally been recognized as the main reason for tropical coral reef degradation, but there are few long-term records of coral bleaching events. In this study, trace metals including chromium(Cr), copper(Cu), molybdenum(Mo), manganese(Mn), lead(Pb), tin(Sn), titanium(Ti), vanadium(V), and yttrium(Y), were analyzed in two Porites corals collected from Meiji Reef in the tropical South China Sea(SCS) to assess differences in trace metal concentrations in bleached compared with unbleached coral growth bands. Ti, V, Cr, and Mo generally showed irregular fluctuations in both corals. Bleached layers contained high concentrations of Mn, Cu, Sn, and Pb. Unbleached layers showed moderately high concentrations of Mn and Cu only. The different distribution of trace metals in Porites may be attributable to different selectivity on the basis of vital utility or toxicity. Ti, V, Cr, and Mo are discriminated against by both coral polyps and zooxanthellae, but Mn, Cu, Sn, and Pb are accumulated by zooxanthellae and only Mn and Cu are accumulated by polyps as essential elements. The marked increase in Cu, Mn, Pb, and Sn are associated with bleaching processes, including mucus secretion, tissue retraction, and zooxanthellae expulsion and occlusion. Variation in these trace elements within the coral skeleton can be used as potential tracers of short-lived bleaching events. 展开更多
关键词 trace metals Porites zooxanthellae coral bleaching Meiji Reef South China Sea
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Numerical simulation and experimental study on constant amplitude fatigue behavior of welded cross plate-hollow sphere joints 被引量:2
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作者 Jiao Jinfeng Lei Honggang Chen Y Frank 《Journal of Southeast University(English Edition)》 EI CAS 2018年第1期62-70,共9页
In order to reveal the constant-fatigue fracture form and mechanism of the welded cross plate-hollow sphere joints(WCPHSJs)and establish its formula,the WCPHSJs were fatigue tested.A total of 19 specimens were tested ... In order to reveal the constant-fatigue fracture form and mechanism of the welded cross plate-hollow sphere joints(WCPHSJs)and establish its formula,the WCPHSJs were fatigue tested.A total of 19 specimens were tested under constant amplitude fatigue loads using a specially designed test rig.The joint was analyzed statically by t e finite element analysis(F3A),and metallographic analysis of fatigue fracture was done by the electron scanning microscope.Numerical simulation and experimental results show that the hot-spot of WCPHSJ lies at the weld toe location where severe stress is concentrated.Fatigue cracks initiate at the weld toe and then propagate circumferentially around the sphere with a diameter equivalent to the width of the cross plate up to the fatigue facture.The initial welding defects and constructional detail constitute the main factor of fatigue failure.The S-N curves for the joints were developed through a linear regession analysis of fatigue data.A formula for calculating constant amplitude fatigue,base on the concept of the hot spot stress amplitude,is proposed. 展开更多
关键词 welded cross plate-hollow sphere joint constant amplitude load finite element analysis S-N curve
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New Method for the Determination of Ionization Constants of Polyprotic Weak Acid
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作者 王静康 郝红勋 《Transactions of Tianjin University》 EI CAS 2003年第2期98-100,共3页
A new method for the determination of ionization constants of polyprotic weak acids is presented. Based on dissociation equilibrium,mass balance and charge balance, the mathematic model is established and the non line... A new method for the determination of ionization constants of polyprotic weak acids is presented. Based on dissociation equilibrium,mass balance and charge balance, the mathematic model is established and the non linear least squares Gauss Newton method is applied to numerically solve the model equations. In order to get the concentration of hydrogen ion, the Debye Hückel equation is used to calculate its activity coefficient. The ionization constants of H 2SO 3 and H 2C 2O 4 obtained by this method are in good agreement with the literature values. 展开更多
关键词 ionization constants polyprotic weak acid pH value Gauss Newton method
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Simulation of seafloor electrical resistivity measuring equipment based on 3D finite element method
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作者 NAN Zeyu FAN Xiaomin ZHANG Yi XU Jun 《Global Geology》 2012年第2期172-175,共4页
In order to explore the mineral resources buried in sea mud,it is necessary to use seabed resistivity measuring equipment,which works closer to the sediments than ordinary ship-based geophysical measuring equipment. B... In order to explore the mineral resources buried in sea mud,it is necessary to use seabed resistivity measuring equipment,which works closer to the sediments than ordinary ship-based geophysical measuring equipment. Because of the harsh environment of seafloor,high pressure and highly conductive seawater,marine magnetotelluric method developed slowly. The sea floor environment is similar to the environment of logging, According to the design of dual lateral logging equipment,a new equipment for seafloor electrical resistivity measurement is designed. Four 3D FEM models that contain resistivity abnormal targets are built to test the ability of this equipment to locate different shape of shallow buried resistivity abnormal targets in sea mud. The authors propose the method to correct the response curve while the bottom surface of this equipment is suspended or not parallel to the seafloor. The resistivity of targets can be calculated accurately. 展开更多
关键词 3D FEM method dual later log gas hydrate polymetallic nodules seafloor electrical resistivity measurement equipment
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Evaluation of Gold Geochemical Anomalies in the Liaodong Paleorift
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作者 XU Shan WANG Miao +1 位作者 LIU Changchun LI Shouyi 《International Journal of Technology Management》 2013年第1期124-128,共5页
89 Au geochemical anomalies are delineated by using 1/200000 regional geochemical exploration data. By researching regional geochemical characteristics and the relationship with the geological background, the author p... 89 Au geochemical anomalies are delineated by using 1/200000 regional geochemical exploration data. By researching regional geochemical characteristics and the relationship with the geological background, the author points out that: the main factors causing high background of Au geochemical anomalies are Gaixian and Dashiqiao formation of Liaohe group, intrusions of Mesozoic intermediate-acid intrusive rocks. The elements combination types of typical anomalies are determined by using factorial analysis,cluster analysis and other mathematical methods with the combination of elements association in typical anomalies:the composite anomaly of Baiyun gold deposits is Au-As-Sb, Maoling gold deposit is Au-As- Bi-Mo, Wulong gold deposits is Au-As-Bi-W, Xiaotongjiapuzi gold deposit is Au-As-Bi-Mo-Sb. By using multivariate statistical analysis method,62 ore-caused anomaly are preferred in 89 Au geochemical anomalies delineated. On this basis, the 62 anomalies are divided into 4 kinds of anomaly types reference to elements combination types of typical anomalies,the classification results of ore-caused anomalies are: 4 geochemical anomalies of Baiyun type,36 geochemical anomalies of Maoling type,11 geochemical anomalies of Wulong type, 11 geochemical anomalies of Xiaotongjapuzi type. According to the results, the prospecting direction is provided for the futme of gold exploration. 展开更多
关键词 Liaodong paleofrifta Geochemical Anomaly Multivariate Statistical Analysis Ore-caused Anomalies
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概率语义与句子系统 被引量:1
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作者 李小五 《哲学研究》 CSSCI 北大核心 2000年第4期73-78,80,共7页
本文讨论概率语义与句子系统的关系,我们考虑的概率语义分两种:句子型的语义和命题型的语义。令L0是由可数个句符和常用句子联结词构成的语言,令L L0是任意句子语言,即L还可以有(作用在句子上的)n元算子。
关键词 语义条件 常元 逻辑 命题 经典 句子 概率
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常春藤皂苷元对前列腺癌DU145细胞增殖、迁移和侵袭能力的影响 被引量:18
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作者 赵振霞 赵振敏 赵成广 《中药药理与临床》 CSCD 北大核心 2017年第1期37-41,共5页
目的:探讨常春藤皂苷元对前列腺癌细胞增殖、迁移和侵袭能力的影响,以及可能的机制。方法:培养人前列腺癌细胞株DU145,分别加入不同浓度常春藤皂苷元(25、50、100μg/ml)作用于DU145细胞,继续培养12、24、36、48h,采用MTT法检测不同浓... 目的:探讨常春藤皂苷元对前列腺癌细胞增殖、迁移和侵袭能力的影响,以及可能的机制。方法:培养人前列腺癌细胞株DU145,分别加入不同浓度常春藤皂苷元(25、50、100μg/ml)作用于DU145细胞,继续培养12、24、36、48h,采用MTT法检测不同浓度常春藤皂苷元对DU145细胞增殖的影响;流式细胞术检测细胞凋亡;利用Transwell小室检测细胞迁移和侵袭能力;利用实时荧光定量PCR检测Bcl-2、Bax、PI3K、Akt基因表达,利用Western blot检测Bcl-2、Bax、PI3K、p-PI3K、Akt和p-Akt蛋白表达。结果:随着常春藤皂苷元浓度(25、50、100μg/ml)的增加,可显著抑制DU145细胞的增殖,这种抑制作用具有时间和剂量依赖性;随着常春藤皂苷元浓度(25、50、100μg/ml)的增加,DU145细胞细胞凋亡率升高;与对照组相比,常春藤皂苷元能显著抑制DU145细胞迁移和侵袭能力;常春藤皂苷元不同浓度组处理DU145细胞48h后,随着常春藤皂苷元浓度升高,Bcl-2、PI3K、Akt mRNA和蛋白相对表达量下降,而Bax mRNA和蛋白相对表达量升高。结论:常春藤皂苷元可抑制前列腺癌细胞增殖、迁移及侵袭能力,促进细胞凋亡发生,且表现出一定的剂量-反应关系,其机制可能与抑制PI3K/Akt信号通路有关。 展开更多
关键词 常春藤皂苷元 前列腺癌 细胞增殖 细胞凋亡 PI3K/AKT信号通路
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