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Properties Correlations and Characterization of Athabasca Oil Sands-derived Synthetic Crude Oil 被引量:1
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作者 Wang Jun Zhao Suoqi +1 位作者 Xu Chunming Chung Keng H. 《Petroleum Science》 SCIE CAS CSCD 2007年第3期84-90,共7页
Narrow fractions of Athabasca oil sands-derived synthetic crude oil (SCO) from Canada were obtained by distillation at 20 ℃ to 500 ℃ and characterized. The yield and properties, such as density, refractive index, ... Narrow fractions of Athabasca oil sands-derived synthetic crude oil (SCO) from Canada were obtained by distillation at 20 ℃ to 500 ℃ and characterized. The yield and properties, such as density, refractive index, viscosity, freezing point, sulfur and nitrogen content and UOP K-index, were correlated as a function of boiling temperature (Tb). The properties of naphtha fractions, jet fuel and diesel fractions could be predicted accurately with the correlations, which are useful for process design considerations, such as optimizing operating conditions of refinery processing units. The other key properties and characteristics of naphtha fractions, jet fuel, diesel and vacuum gas oil were also determined. 展开更多
关键词 SCO PROPERTIES correlation characterIZATION
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Correlations of the Characteristics of Photosynthates between Female Parent and F_1 Inter-subspecific Hybrids of Rice
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作者 廖色梅 邓应德 +2 位作者 翟少华 张海清 石书兵 《Agricultural Science & Technology》 CAS 2016年第7期1513-1518,共6页
The utilization of hybrid rice heterosis between subspecies is an important way to prove rice breeding programs, but the low matter conversion rate of inter- subspecific hybrids becomes the bottleneck to get high yiel... The utilization of hybrid rice heterosis between subspecies is an important way to prove rice breeding programs, but the low matter conversion rate of inter- subspecific hybrids becomes the bottleneck to get high yield. To further explore the reasons for the low conversion rate of dry matters, and the coordination mechanism between biological yield's potential and grain yield's potential, we evaluated the correlations of the agronomic characters between the female parent and F1 inter subspecific hybrids, using a male parent R292, three female parents Y58S, Peiai 64S and 83S, and their hybrid combinations Y58S/292, 64S/292 and 83S/292 as experimental materials, Yueyou 9113 as the control. The results indicated that the contents of both soluble sugar and starch of all the experimental materials varied at different growth stages, and the highest starch content appeared at pre-ripening stage while soluble sugar content was the lowest. Notable positive correlations in a- gronomic characteristics were observed between the female parents and their F1 hybrids. The soluble sugar content in stem was the highest, followed by that in panicle, and the soluble sugar content in sheath and flag leaf was lower. The re- sults provide a theoretical basis for the research on heterosis and yield coordination mechanisms of inter-subspecific hybrids of rice. 展开更多
关键词 Inter-subspecific hybrids of rice Soluble sugar STARCH correlATION
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Tropical Clayey Sand Soil's Behaviour Analysis and Its Empirical Correlations via Geophysics Electrical Resistivity Method and Engineering Soil Characterizations 被引量:3
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作者 Andy Anderson Bery Rosli Saad 《International Journal of Geosciences》 2012年第1期111-116,共6页
Soil is a heterogeneous medium which consist of liquid, solid, and gaseous phases. The solid and liquid phases play an essential role in soil spontaneous electrical phenomena and in behaviour of electrical fields, art... Soil is a heterogeneous medium which consist of liquid, solid, and gaseous phases. The solid and liquid phases play an essential role in soil spontaneous electrical phenomena and in behaviour of electrical fields, artificially created in soil. Soil electrical properties are the parameters of natural and artificially created electrical fields in soils and influenced by distribution of mobile electrical charges, mostly inorganic ions, in soils. Geophysical method of electrical resistivity was used for measuring soil electrical properties and tested in different soil studies. Laboratory tests were performed for the numbers of clayey sandy soil samples taken from Batu Uban area. The empirical correlations between electrical parameter, percentage of liquid limit, plastic limit, plasticity index, moisture content and effective soil cohesion were obtained via curvilinear models. The ranges of the soil samples are changed between 229 Ωm to 927 Ωm for resistivity (ρ), 6.01 kN/m2 to 14.27 kN/m2 for effective soil cohesion (C'), 35.08 kN/m2 to 51.47 kN/m2 for internal fiction angle (?'), 38% to 88% for moisture content (W), 33% to 78% for liquid limit (WL), 21% to 43% for plastic limit (Wp) and 11% to 35% for plasticity index (PI). These empirical correlations model developed in this study provides a very useful tool to relate electrical resistivity with effective cohesion, internal friction angle (strength), void ratio, porosity, degree of saturation, moisture content, liquid limit, plastic limit and plasticity index in context of medium-grained of clayey sandy soil that is, its fluid behaviours. 展开更多
关键词 Empirical correlations Regression Coefficient RESISTIVITY Moisture Content Fluid BEHAVIOURS
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Clinical characteristics and clinicopathological correlations of bilateral breast cancer in China:A multicenter study from Chinese Society of Breast Surgery(CSBrS-006) 被引量:4
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作者 Xuelu Li Yitong Wang +5 位作者 Bo Pan Man Li Jiyue Gao Yi Zhao Zuowei Zhao Chinese Society of Breast Surgery 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2021年第1期27-32,共6页
Objective:To investigate the clinical characteristics and clinicopathological correlations of bilateral breast cancer(BBC)in China.Methods:Data of 440 patients diagnosed with BBC in 2018 were collected from 33 centers... Objective:To investigate the clinical characteristics and clinicopathological correlations of bilateral breast cancer(BBC)in China.Methods:Data of 440 patients diagnosed with BBC in 2018 were collected from 33 centers of the Chinese Society of Breast Surgery.Demographic characteristics,bilateral tumor characteristics,and comprehensive treatment data were obtained.Correlations between the clinicopathological characteristics of bilateral tumors were analyzed.Results:The proportion of BBC was 0.22%-3.08%.A total of 33(7.5%)patients had a family history of malignant tumors,304(69.1%)patients had synchronous BBC.Only 1(0.2%)patient was male.More than half of all patients received concurrent or asynchronous endocrine/chemotherapy,32.5%of all human epidermal growth factor receptor 2(HER2)-positive patients received HER2-targeted therapy,and approximately 21.6%of all patients received radiotherapy.The most common pathological cancer type was invasive ductal cancer(>60%).Approximately 70%of all patients had bilateral hormone receptor(HR)-positive tumors and presented with a single breast mass.Significant correlations were found with pathological type,histological grade,locations of tumor,molecular subtype,Ki-67 index,tumor site and size of bilateral tumors.Results of the subgroup analysis showed more clinicopathological characteristics when synchronous BBC was compared with metachronous BBC.Conclusions:In China,the clinicopathological characteristics of bilateral tumors showed significant correlations,and more significant clinicopathological correlations were observed when synchronous BBC was compared with metachronous BBC. 展开更多
关键词 Adjuvant therapy bilateral breast cancer clinicopathological correlation demographic characteristics
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A generalized set of correlations for plus fraction characterization
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作者 JAMIALAHMADI Mohamad ZANGENEH Hossein HOSSEINI Seyed Sajad 《Petroleum Science》 SCIE CAS CSCD 2012年第3期370-378,共9页
The importance of accurate determination of the critical properties of plus fractions in prediction of phase behaviour of hydrocarbon mixtures by equations of state is well known in the petroleum industry. It has been... The importance of accurate determination of the critical properties of plus fractions in prediction of phase behaviour of hydrocarbon mixtures by equations of state is well known in the petroleum industry. It has been stated in various papers (Elsharkawy, 2001) that using the plus fraction as a single group in equation of state calculations reduces the accuracy of the results. However in this work it has been shown that using the proper values of critical temperature and pressure for the plus fraction group can estimate the properties of hydrocarbon mixtures, and they are accurate enough to be used in reservoir engineering and enhanced oil recovery calculations. In this paper, a new method is proposed for calculating the critical properties of plus fractions of petroleum fluids. One can use this method either in predicting critical pressure and temperature of single carbon numbers (SCNs) after the splitting process or in predicting critical pressure and temperature of the plus fraction as a single group. A comparison study is performed against Riazi-Daubert correlation (Riazi and Daubert, 1987) and Sancet correlations (Sancet, 2007) for 25 oil samples taken from 14 fields from southwest Iran. The results indicate the superiority of the proposed method to the Riazi-Daubert and Sancet correlations. 展开更多
关键词 Plus fraction critical properties correlation single carbon number bubble point calculations
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Characterization of the pairwise correlations in different quantum networks consisting of four-wave mixers and beamsplitters
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作者 祁健 忻俊 +1 位作者 王海龙 荆杰泰 《Chinese Physics B》 SCIE EI CAS CSCD 2017年第7期153-160,共8页
We investigate the performances of the pairwise correlations(PCs) in different quantum networks consisting of fourwave mixers(FWMs) and beamsplitters(BSs). PCs with quantum correlation in different quantum netwo... We investigate the performances of the pairwise correlations(PCs) in different quantum networks consisting of fourwave mixers(FWMs) and beamsplitters(BSs). PCs with quantum correlation in different quantum networks can be verified by calculating the degree of relative intensity squeezing for any pair of all the output fields. More interestingly, the quantum correlation recovery and enhancement are present in the FWM+BS network and the repulsion effect phenomena(signal(idler)-frequency mode cannot be quantum correlated with the other two idler(signal)-frequency modes simultaneously)between the PCs with quantum correlation are predicted in the FWM + FWM and FWM + FWM + FWM networks. Our results presented here pave the way for the manipulation of the quantum correlation in quantum networks. 展开更多
关键词 pairwise correlation four-wave mixer degree of relative intensity squeezing quantum network
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Characterizing Quantum Correlations in Arbitrary-Dimensional Bipartite Systems Using Hurwitz's Theory
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作者 LI Hui 《Communications in Theoretical Physics》 SCIE CAS CSCD 2014年第3期273-280,共8页
Quantum correlations play vital roles in the quantum features in quantum information processing tasks. Among the measures of quantum correlations, quantum discord (QD) and entanglement of formation (EOF) axe two s... Quantum correlations play vital roles in the quantum features in quantum information processing tasks. Among the measures of quantum correlations, quantum discord (QD) and entanglement of formation (EOF) axe two significant ones. Recent research has shown that there exists a relation between QD and EOF, which makes QD more significant in quantum information theory. However, until now, there exists no general method of chaxaeterizing quantum discord in high-dimensional quantum systems. In this paper, we have proposed a general method for calculating quantum discord in axbitraxy-dimensionM bipaxtite quantum systems in terms of Hurwitz's theory. Applications including the Werner state, the spin-1 XXZ model thermal equilibrium state, the Horodecki state, and the separable-bound-free entanglement state are investigated. We present the method of obtaining the EOF of axbitraxy-dimensional bipaxtite quantum states via purification, and the relations.hip between QD and EOF. 展开更多
关键词 quantum correlation quantum discord entanglement of formation
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Genetic and Correlation Analysis of Grain Characters in Three-line Hybrid Rice 被引量:11
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作者 邹小云 邓辉明 +6 位作者 傅军如 彭小松 朱昌兰 贺晓鹏 陈小荣 贺浩华 刘宜柏 《Agricultural Science & Technology》 CAS 2009年第2期77-81,共5页
Abst[Objective] This study was to understand the genetic dynamics of three-line hybrid rice, and explore the respective effect of sterile line and restoring line on grain characters of hybrid rica. [Method] Four three... Abst[Objective] This study was to understand the genetic dynamics of three-line hybrid rice, and explore the respective effect of sterile line and restoring line on grain characters of hybrid rica. [Method] Four three-line stedle lines and 27 restoring lines(cultivars) commonly culti- vated in Central China region were regarded as expadmental materials to conduct 4 x27NCII cross design, and the grain characters of three-line hybrid rico were analyzed at genetic and correlation levels. [ Result] Four characters of grain length, grain width, 1 000-grain weight and length- width ratio play the leading role in additive gene effect; these four characters were simultaneously influenced by male parent and female parent, but the effect from male parent was relatively larger. The grain length, grain width, 1 000-grain weight and length-width ratio all have high brood hedtabUities( respectively 99.65%, 98.31%, 95.27% and 98.81% ). Correlation analysis showed that grain length was positively correlated with 1 000-grain weight and length-width ratio at extremely significant level; 1 000-grain weight was positively correlated with grain length and length- width ratio at extremely significant level, and was insignificantly correlated with grain width; grain width was negatively correlated with grain length and length-width ratio at extremely significant level. Path analysis showed that the direct path coefficients of grain length, grain width and 1 0(30- grain weight to length-width ratio were 0.624 6, -0.555 9 and -0.015 8, respectively. [ Conclusion] This study systematically analyzed the effects of stedle line and restoring line on grain characters of hybrid rice, which provided theoretical basis for breeding high quality and yield hy- brid dce. 展开更多
关键词 Three-line hybrid dce Grain characters INHERITANCE . correlation
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Correlations among Important Fruit Quality and Plant Characteristics of Some Fig Genotypes
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作者 A. Aytekin Polat Oguzhan Caliskan 《Journal of Life Sciences》 2017年第3期141-144,共4页
Experiments were carried to determine correlations of important fruit and plant characteristics using 30 fig genotypes. The correlation coefficients between these traits were calculated using SAS program. Fruit weight... Experiments were carried to determine correlations of important fruit and plant characteristics using 30 fig genotypes. The correlation coefficients between these traits were calculated using SAS program. Fruit weight, fruit diameter, fruit length, neck length, ostiolium width, abscission of the stalk from the twig, ease of peeling, fruit skin cracks, thickness of the fruit skin, texture of skin, fruit ribs, fruit internal cavity, TSS (total soluble solids), pH, acidity, TSS/acidity, trunk diameter, shoot length, yield per tree were traits examined in the study. According to five-year data, fruit weight was found to have positive correlation by fruit diameter (r = 0.92; P 〈 0.01), fruit length (r = 0.81; P 〈 0.01), neck length (r = 0.35; P 〈 0.01), ostiolium width (r = 0.23; P 〈 0.01), trunk diameter (r = 0.26; P 〈 0.01), fruit skin cracks (r = 0.26; P 〈 0.01) and negative correlation by TSS (r = -0.26; P 〈 0.01) and fruit ribs (r = -0.21; P 〈 0.01). Relations between some traits such as ostiolium width, abscission of the stalk from the twig, ease of peeling, fruit skin cracks, texture of skin and fruit ribs are deviated based on the years. Some relationships between fig fruit characteristics exist, which may help researchers to solve some problems such as ostiolium width and fruit skin cracking. These studies may contribute to producing fruit with a good quality and help to evaluate new cultivars. 展开更多
关键词 Fig genotype fruit quality plant characteristic correlation.
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Selection of characteristic spectral bands for the analysis by the NIR correlation coefficient method 被引量:4
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作者 刘婷 冯艳春 +1 位作者 宋丹青 胡昌勤 《Journal of Chinese Pharmaceutical Sciences》 CAS 2011年第1期83-91,共9页
We analyzed the infrared 0R)-near infrared (NIR) 2D correlation spectra of drugs perturbed by temperature. By identification of functional groups by IR spectrum and by the correlation analysis of IR-NIR spectrum, w... We analyzed the infrared 0R)-near infrared (NIR) 2D correlation spectra of drugs perturbed by temperature. By identification of functional groups by IR spectrum and by the correlation analysis of IR-NIR spectrum, we identified the characteristic spectral bands that were closely related to the structure of a drug substance of interest. These characteristic spectral bands were relatively less interfered by other ingredients for analysis by the NIR correlation coefficient method. With these characteristic spectral bands, the accuracy of screening illegally added Sildenafil citrate, Tadalafil and Metforrnin hydrochloride in Chinese patent drugs and healthcare products reached about 90%, which met the requirements of rapid screening. 展开更多
关键词 Two-dimensional correlation spectroscopy NIR correlation coefficient method by characteristic spectral bands Chinese patent drug Illegal additive
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Correlation Analysis of Characters of Indica Hybrid Rice with High Content of Amylose 被引量:4
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作者 杨扬 况浩池 +4 位作者 曾正明 罗俊涛 陈光珍 何兴材 付均 《Agricultural Science & Technology》 CAS 2013年第3期475-477,共3页
[Objective] The aim was to research and analyze characters and related correlation of indica hybrid rice containing high amylose. [Method] In the research, major characters of 16 species of groups of {ndica hybrid ric... [Objective] The aim was to research and analyze characters and related correlation of indica hybrid rice containing high amylose. [Method] In the research, major characters of 16 species of groups of {ndica hybrid rice and the correlation were explored in rice belts in Sichuan in 2011. [Result] The variation of chalkiness degree was the highest at 26.8%, followed by rate of head rice at 22.89%; varia- tions of head rice rate and chalkiness degree were lower at 0.72% and 2.61%. In addition, rate of unpolished rice was of significantly negative correlation with chalki- ness degree; rate of chalky rice was of extremely positive correlation with chalkiness degree and gel consistency; chalkiness degree was of significantly positive correla- tion with gel consistency; gel consistency was of significantly negative correlation with protein content; amylose content was of insignificant correlation with gel consis- tency (r=0.166 9) of the 16 hybrid groups. These indicated that gel consistency would be still high as the content of amylose grows (AC≥25%). For example, when the content of anylose in Chuanxiang 29A/Luhui 37, Kangfeng AJ6684, and Lefeng A/SR536 exceeded 27%, the gel consistency was over 80 mm in the research. [Conclusion] The research provides references for improvement of amylose content in breeding hybrid rice. 展开更多
关键词 Higher amylose content Indica hybrid rice characterS correlaiton analysis
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CHARACTERISTICS OF FAN STALLING BASED ON CORRELATED DIMENSIONS 被引量:2
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作者 谷勇霞 周忠宁 李意民 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 2011年第4期362-366,共5页
Different from the previous qualitative analysis of linear systems in time and frequency domains, the method for describing nonlinear systems quantitatively is proposed based on correlated dimensions. Nonlinear dynami... Different from the previous qualitative analysis of linear systems in time and frequency domains, the method for describing nonlinear systems quantitatively is proposed based on correlated dimensions. Nonlinear dynamics theory is used to analyze the pressure data of a contrarotating axial flow fan. The delay time is 18 and the embedded dimension varies from 1 to 25 through phase-space reconstruction. In addition, the correlated dimensions are calculated before and after stalling. The results show that the correlated dimensions drop from 1. 428 before stalling to 1. 198 after stalling, so they are sensitive to the stalling signal of the fan and can be used as a characteristic quantity for the judging of the fan stalling. 展开更多
关键词 fan with contra-rotating axis fan stalling correlated dimensions phase-space reconstruction
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Canonical Correlation Analysis of Agronomic Characters of Brassica juncea in Western China
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作者 大次卓嘎 王建林 +1 位作者 次仁央金 王忠红 《Agricultural Science & Technology》 CAS 2011年第11期1600-1604,1666,共6页
[Objective] The study aimed at exploring the relationship among the agronomic characters of B. juncea in western China, in order to provide scientific basis for the breeding of B. juncea in western China. [Method] 39 ... [Objective] The study aimed at exploring the relationship among the agronomic characters of B. juncea in western China, in order to provide scientific basis for the breeding of B. juncea in western China. [Method] 39 B. juncea materials from western China were used for the canonical correlation analysis, and canonical correlations between each pair of the four ecological character (containing 18 variables) were verified, including yield characters (5 variables), caulis characters (6 variables), branch characters (3 variables) and pod characters (3 variables). [Result] Yield per plant of B. juncea in western China suffered a tremendous influence from effective pod number per plant while was not significantly affected by the total pod number per plant, seed number per pod and 1 000-seed weight; the most important character related with the yield character of B. juncea in western China was caulis character, followed by the branch character and pod character; yield characters, caulis characters, branch characters and pod characters of B. juncea in western China were closely correlated. [Conclusion] In order to improve the yield characters of B. juncea in western China, caulis characters should be focused on, followed by branch characters and pod characters; rapeseed varieties with high performance in total pod number per plant and effective pod number per plant should be chosen through the perspectives of effective branch number, plant height, pod number of main inflorescence, fruit stalk number of main inflorescence and other traits, while rapeseed varieties with high performance in seed number per pod and 1 000-seed weight should be chosen through the perspectives of beak length and other traits. 展开更多
关键词 Western China Brassica juncea Ecological character Canonical correlation analysis Comparative study
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Correlation between vibrational modes and structural characteristics of Ba[(Zn_(1-x)Mg_x)_(1/3)Ta_(2/3)]O_3 solid solutions
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作者 石锋 Helei Dong 《功能材料信息》 2014年第1期8-14,共7页
Ba[(Zn_(1-x)Mg_x)_(1/3)Ta(2/3)]O_3(BZMT,x=0,0.2,0.4,0.6,0.8,and 1.0)solid solution ceramics were synthesized by a conventional solid-state sintering technique.Vibration spectra(Raman spectroscopy and Fourier trans for... Ba[(Zn_(1-x)Mg_x)_(1/3)Ta(2/3)]O_3(BZMT,x=0,0.2,0.4,0.6,0.8,and 1.0)solid solution ceramics were synthesized by a conventional solid-state sintering technique.Vibration spectra(Raman spectroscopy and Fourier trans form far-infrared reflection spectroscopy)and X-ray diffraction(XRD)were employed to evaluate the correla tion between microstructures and phonon modes of these solid solutions.Spectroscopic and structural data show sensitivity to structural evolution of samples with Mg^(2+)concentration,and a 1:2 ordered phase appears when x≥0.2.The unit cell parameters decrease with increasing Mg^(2+)content.The ordering degree reaches a relative maximum value in the range of Mg^(2+)content,0.4≤x<0.6.The phonon modes were assigned,and the correlation of phonon vibrations in the microstructure were analyzed.The position and width of the phonon modes were determined and correlated to the ionic radii for the different atoms substituted in the B'-site. 展开更多
关键词 correlATION CERAMICS PHONON SINTERING VIBRATIONAL
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明恩溥的无本译写:Chinese Characteristics的版本流变与人物特质
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作者 苏蕊 亚晓晗 《外国语文研究》 2025年第2期55-71,共17页
Chinese Characteristics作为重要的域外文献,以他者视野译写了晚清时期中国社会面貌及中国人特征。本研究以无本译写为主体理据,首先通过版本流变考察明恩溥在译写语言上的特点,由此反观其译写意图及思想来源,并深入剖析其思维认知的改... Chinese Characteristics作为重要的域外文献,以他者视野译写了晚清时期中国社会面貌及中国人特征。本研究以无本译写为主体理据,首先通过版本流变考察明恩溥在译写语言上的特点,由此反观其译写意图及思想来源,并深入剖析其思维认知的改变;进而针对1894年修订版进行碎片式底本溯源。选取文本中的典型案例,分析其译写语言内部的中国人特质,以期挖掘明恩溥译写现象背后的社会文化因素。本研究对Chinese Characteristics的考释,不仅有助于了解西方人眼中的中国国民特质,还可以此为镜,揭示明恩溥他塑中国形象中的正与偏,为今后借力使力,塑造可信、可敬、可爱的中国形象提供借鉴和参考。 展开更多
关键词 无本译写 底本溯源 版本流变 国民特质 他者视野
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The Distribution Characteristics of Soil pH Values of Tobacco-growing Areas in Dali City and Its Correlation with Soil Nutrients 被引量:1
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作者 杨春文 赵宇 +5 位作者 王新中 杨成伟 杨志娟 户艳霞 孙军伟 王德勋 《Agricultural Science & Technology》 CAS 2015年第5期951-953,972,共4页
[Objective] The aim was to study the distribution characteristics of soil pH values and its correlation with soil nutrients in tobacco-growing areas. [Method] Soil nutrients of 43 samples from tobacco-growing areas in... [Objective] The aim was to study the distribution characteristics of soil pH values and its correlation with soil nutrients in tobacco-growing areas. [Method] Soil nutrients of 43 samples from tobacco-growing areas in Dali City were analyzed.[Results] The results showed that average pH value of tobacco-planting soil in Dali City was 6.52, soil samples which suited for flue-cured tobacco cultivation accounted for 72.09% of total soil samples. In four soil types of tobacco-growing areas, the pH values in a descending order were as follows: alluvial soil〉 paddy soil 〉purple soil〉 red soil. At the altitude range of 1 780-2 200 m, soil pH values showed a gradual decreasing trend. The average contents of soil organic matters were relatively abundant and generally suited for high-quality tobacco cultivation; the average contents of soil alkali-hydrolyzable nitrogen, available phosphorus, exchangeable calcium and exchangeable magnesium were generally at medium and abundant level, however,their rations under the medium level in some tobacco-growing areas were 6.98%,11.63%, 2.33% and 4.65%, respectively; moreover, soil with lower available potassium contents occupied a large proportion, namely 58.14%. [Conclusion] Soil pH values had significant correlation with exchangeable magnesium and exchangeable magnesium, however, they had no significant correlation with other soil nutrients. 展开更多
关键词 Tobacco-growing areas SOIL pH values Soil nutrients correlation analysis
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Influence of rock property correlation on reliability analysis of rock slope stability: From property characterization to reliability analysis 被引量:9
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作者 Adeyemi Emman Aladejare Yu Wang 《Geoscience Frontiers》 SCIE CAS CSCD 2018年第6期1639-1648,共10页
Cohesion(c) and friction angle(φ) of rock are important parameters required for reliability analysis of rock slope stability. There is correlation between c and φ which affects results of reliability analysis of roc... Cohesion(c) and friction angle(φ) of rock are important parameters required for reliability analysis of rock slope stability. There is correlation between c and φ which affects results of reliability analysis of rock slope stability. However, the characterization of joint probability distribution of c and φ through which their correlation can be estimated requires a large amount of rock property data, which are often not available for most rock engineering projects. As a result, the correlation between c and φ is often ignored or simply assumed during reliability studies, which may lead to bias estimation of failure probability. In probabilistic rock slope stability analysis, the influence of ignoring or simply assuming the correlation of the rock strength parameters(i.e., c and φ) on the reliability of rock slopes has not been fully investigated. In this study, a Bayesian approach is developed to characterize the correlation between c and φ, and an expanded reliability-based design(RBD) approach is developed to assess the influence of correlation between c and φ on reliability of a rock slope. The Bayesian approach characterizes the sitespecific joint probability distribution of c and φ, and quantifies the correlation between c and φ using available limited data pairs of c and φ from a rock project. The expanded RBD approach uses the joint probability distribution of c and φ obtained through the Bayesian approach as inputs, to determine the reliability of a rock slope. The approach gives insight into the propagation of the correlation between c and φ through their joint probability into the reliability analysis, and their influence on the calculated reliability of the rock slope. The approaches may be applied in practice with little additional effort from a conventional analysis. The proposed approaches are illustrated using real c and φ data pairs obtained from laboratory tests of fractured rock at Forsmark, Sweden. 展开更多
关键词 Reliability-based design ROCK SLOPE correlATION Failure PROBABILITY BAYESIAN approach Joint PROBABILITY distribution
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Utilizing On-the-Go Soil Sensors to Explore Correlations between Electrical Conductivity, Soil Reflectance, Slope, and Elevation of Mississippi Farm Soils 被引量:1
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作者 Reginald S. Fletcher 《Agricultural Sciences》 2025年第1期112-122,共11页
Ten physical and environmental variables collected from an on-the-go soil sensor at two field sites (MF3E and MF11S) in Mississippi, USA, were analyzed to assess soil variability and the interrelationships among the m... Ten physical and environmental variables collected from an on-the-go soil sensor at two field sites (MF3E and MF11S) in Mississippi, USA, were analyzed to assess soil variability and the interrelationships among the measurements. At MF3E, moderate variability was observed in apparent electrical conductivity shallow (ECas), slope, and ECa ratio measurements, with coefficients of variation ranging from 20% to 27%. In contrast, MF11S exhibited higher variability, particularly in ECas and ECad (deep) measurements, which exceeded 30% in their coefficient of variation values, indicating significant differences in soil composition and moisture content. Correlation analysis revealed strong positive relationships between the near-infrared-to-red ratio and red reflectance (r = 0.897***) soil values at MF3E. MF11S demonstrated a strong negative correlation between ECas and ECad readings with the x-coordinate (r ***). Scatter plots and fitted models illustrated the complexity of relationships, with many showing nonlinear trends. These findings emphasize the need for continuous monitoring and advanced modeling to understand the dynamic nature of soil properties and their implications for agricultural practices. Future research should explore the underlying mechanisms driving variability in the soil characteristics to enhance soil management strategies at the study sites. 展开更多
关键词 Mobile Soil Sensors NEAR-INFRARED correlation Nonlinear
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Characterization for elastic constants of fused deposition modelling-fabricated materials based on the virtual fields method and digital image correlation 被引量:4
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作者 Quankun Cao Huimin Xie 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2017年第6期1075-1083,共9页
Fused deposition modelling(FDM), a widely used rapid prototyping process, is a promising technique in manufacturing engineering. In this work, a method for characterizing elastic constants of FDM-fabricated materials ... Fused deposition modelling(FDM), a widely used rapid prototyping process, is a promising technique in manufacturing engineering. In this work, a method for characterizing elastic constants of FDM-fabricated materials is proposed. First of all, according to the manufacturing process of FDM, orthotropic constitutive model is used to describe the mechanical behavior. Then the virtual fields method(VFM) is applied to characterize all the mechanical parameters(Q, Q, Q, Q) using the full-field strain,which is measured by digital image correlation(DIC). Since the principal axis of the FDM-fabricated structure is sometimes unknown due to the complexity of the manufacturing process, a disk in diametrical compression is used as the load configuration so that the loading angle can be changed conveniently. To verify the feasibility of the proposed method, finite element method(FEM) simulation is conducted to obtain the strain field of the disk. The simulation results show that higher accuracy can be achieved when the loading angle is close to 30?. Finally, a disk fabricated by FDM was used for the experiment. By rotating the disk, several tests with different loading angles were conducted. To determine the position of the principal axis in each test, two groups of parameters(Q, Q, Q, Q) are calculated by two different groups of virtual fields. Then the corresponding loading angle can be determined by minimizing the deviation between two groups of the parameters. After that, the four constants(Q, Q, Q, Q) were determined from the test with an angle of 27?. 展开更多
关键词 Fused deposition modelling Virtual fields method Digital image correlation Orthotropic constitutive model Disk compression
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Characterization of gold nanoparticle bioconjugation by resonance light scattering correlation spectroscopy 被引量:2
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作者 Xin Qiu Li Chuan Tang Chao Qing Dong Ji Cun Ren 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第10期1227-1230,共4页
Gold nanoparticles (GNPs) have been widely used as probes and nanomaterials in certain biological and biomedical fields thanks to its special physical and chemical properties. However, it is still difficult to chara... Gold nanoparticles (GNPs) have been widely used as probes and nanomaterials in certain biological and biomedical fields thanks to its special physical and chemical properties. However, it is still difficult to characterize GNPs-bioconjugates in solution, which has greatly limited further bioapplications of GNPs. In this study, we reported a single particle method for characterizing GNPs- biomolecules in solution using resonance light scattering correlation spectroscopy (RLSCS). The interaction of GNPs with bovine serum albumin (BSA) and thiol-modified oligonucletides were investigated. 展开更多
关键词 Resonance light scattering correlation spectroscopy Gold nanoparticle INTERACTION Biomolecules
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