40 research outputs found
Victoria cruziana Orbigin
No full text5.1. Growth condition of V. cruziana Orbigin V. cruziana Orbign. (Nymphaeaceae) plants were grown in square ponds of 80 cm in depth in Hangzhou (N30 ◦ 6 ′ 54 ′′, E120 ◦ 6 ′ 36 ′′), China. Plants were applied with constant conditions of fertilization, irrigation, disease prevention, and pesticide application. The flowers were collected on the first day of full blooming.Published as part of Jiang, Yifan, Liu, Guanhua, Zhang, Wanbo, Zhang, Chi, Chen, Xinlu, Chen, Yuchu, Yu, Cuiwei, Yu, Dongbei, Fu, Jianyu & Chen, Feng, 2021, Biosynthesis and emission of methyl hexanoate, the major constituent of floral scent of a night-blooming water lily Victoria cruziana, pp. 1-10 in Phytochemistry (112899) (112899) 191 on page 7, DOI: 10.1016/j.phytochem.2021.112899, http://zenodo.org/record/825821
Joint Kinematics and Sealing Capacity Assessment of Ductile Iron Pipes under Abrupt Transverse Ground Movements
No full textJoint kinematic behaviour, i.e., joint rotation and axial translation, can partially help pipelines to accommodate abrupt ground movements, and cause leaking if joint service limit is exceeded, even without any structural failure. Kinematic behaviour of bell-spigot jointed ductile iron (DI) pipes and its influence on joint sealing capacity under abrupt transverse ground movements are investigated in this study. Firstly, a beam-on-spring finite element analysis on joint kinematics of DI pipes is conducted, in which different fault-pipe crossing positions are implemented. Based on simulated results, a modified joint kinematic solution incorporating pipe deflection and joint shear force under different fault-pipe crossing positions is proposed. Then, a Monte Carlo simulation (MCS)-based reliability assessment procedure for joint sealing capacity is developed. Sensitivity analysis is subsequently conducted to investigate the effects of uncertainties associated with initial axial translation, soil properties, and crossing positions on the joint sealing capacity, and the effects of different deterministic solutions are compared. The proposed method allows engineers to effectively evaluate how the joint sealing capacity of DI pipes changes with consideration of uncertainties when abrupt transverse ground movements are encountered.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author
Effects of Parameter Uncertainties on Interaction between Submarine Telecommunication Cables and Lateral Seabed Movements
No full textSubmarine telecommunication cables are the physical backbone of the Internet. They are often buried shallowly beneath seabed and affected by seabed movements. Due to the long distance of cables and the complexity of submarine environment, interaction between cables and seabed movements inevitably involves various parameter uncertainties. However, effects of parameter uncertainties on submarine cable responses to seabed movements have not been fully investigated. This paper aims to address this problem using random finite element method (RFEM) that integrates finite element (FE) analysis with Monte Carlo simulation (MCS). First, deterministic FE analysis is performed to investigate cable responses to lateral seabed movements. Then MCS is implemented to study the effects of parameter uncertainties on cable responses. Statistical analysis of the MCS results is performed to prioritize the effects of parameter uncertainties on cable damage probability. Random field is also used to model spatial variability of soil parameters. Effect of the correlation length on cable damage probability is investigated. The results show that uncertainty of the anchored cable length La has the most significant effect on cable damage probability, while the effects of uncertainties in soil friction angle ϕ and effective unit weight γ′ are minor. Ignoring spatial variability of soil parameters may lead to significant misjudgment of cable damage risk
Numerical and physical modeling of submarine telecommunication cables subjected to abrupt lateral seabed movements
No full textSubmarine telecommunication cables, which carry about 99% of international telecommunications, are usually buried shallowly beneath seabed and vulnerable to seabed movements. In recent years, many submarine cable damages have been observed when significant lateral seabed movements occur due to geohazards, e.g., offsets of strike-slip faults and submarine landslides. However, research on the interaction between submarine telecommunication cables and lateral seabed movements is limited. There is no existing method for evaluating the cable safety when subjected to lateral seabed movements. This paper aims to carry out finite element (FE) analysis and physical modeling to investigate the responses of submarine telecommunication cables to lateral seabed movements. A FE model is developed and validated by full-scale physical test results. After validation of the FE model, a series of parametric studies is performed covering typical ranges of soil properties, cable burial depths, cable characteristics and seabed movement characteristics. The parametric study results are summarized in a dimensionless plot, followed by a regression analysis. A simple but effective formula is proposed to predict the maximum cable strains induced by lateral seabed movements. The dominant parameters that control submarine cable responses are identified and incorporated into the formula. Safety criteria for submarine telecommunication cables are also proposed for evaluating the cable safety when subjected to lateral seabed movements.</p
The Pretreatment Method for Epicardial Potential Mapping Signals Based on Independent Component Analysis and Wavelet Transform
No full text
Victoria cruziana
No full text2.1. Chemical profiling of floral scent from V. cruziana during first bloom Combining headspace collection with gas chromatography–mass spectrometry (GC-MS) analysis, four volatile compounds were detected from the fully-opened flowers of V. cruziana during their first bloom (Fig. 1A). These four compounds were identified to be methyl hexanoate, benzyl alcohol, benzyl 2-methylbutanoate and benzyl tiglate. Except benzyl 2-methylbutanoate, the chemical identities of the other three compounds were verified by comparing their chromatograms (Fig. 1B) and mass spectra (Fig. 1C) with those of authentic standards. Among these compounds, methyl hexanoate was the most abundant constituent accounting for 45.5 % of the total emission. Benzyl alcohol, benzyl 2-methylbutanoate and benzyl tiglate accounted for 37.8 %, 11.3 %, and 5.4 % of the total emission, respectively. 2.2. Emission of floral volatiles from different parts of V. cruziana flowers To determine the contribution of different parts of V. cruziana flowers to floral scent profile, the flowers of V. cruziana were divided into sepals, petals, stamen and pistils. These four parts were subjected to headspace collection, separately. The four floral volatiles, i.e. methyl hexanoate, benzyl alcohol, benzyl 2-methylbutanoate and benzyl tiglate, were detected from each of the four parts. (Fig. 2). Of the four parts, stamen showed the highest rates of total emission (36.42 ± 7.6 nmol/g / h). Methyl hexanoate exhibited the highest rates of emission from stamens at 36.31 ± 7.5 nmol/g/h (Fig. 2), followed by pistils (12.11 ± 3.8 nmol/g / h), petals (2.09 ±1.6 nmol/g/h) and sepals (1.31 ± 1.24 nmol/g/h). In contrast, the three benzenoids exhibited the highest rates of emission from the petals with the emission rate of 10.99 ±3.3 nmol/g/h (Fig. 2). Their emission rates from sepals, stamens and pistils were 3.64 ± 1.9 nmol/g/h, 0.11 ± 0.01 nmol/g/h and pistils (0.01 ± 0.001 nmol/g/h), respectively. 2.3. Emission dynamics of floral volatiles from V. cruziana In our observation, the flowers of V. cruziana opened fully at 19:00 on the first day, began to close in the following morning and became completely closed between 12:00 and 13:00. The flowers started to reopen between 16: 00 and 17: 00 on the same day. The representative flowers at the four stages were shown in Fig. 3A. To examine the emission dynamics, floral volatiles of V. cruziana were continuously collected (1-h collection followed by a 3-h interval) for two days (12/12 h light/dark) and analyzed by GC-MS. The emission rates of total volatiles remained constant before a significant drop towards the end of second bloom (Fig. 3B). The emission rates of benzenoids and methyl hexanoate were also analyzed separately. The emission patterns of benzenoids were very similar to those of total volatiles (Fig. 3C). In contrast, there was a reduction in mission rates of methyl hexanoate towards the end of first closure before increasing during the second bloom (Fig. 3D). Like total volatiles, the emission of both benzenoids (Fig. 3C) and methyl hexanoate (Fig. 3D) dropped significantly at the of the end of second bloom and after that. 2.4. Identification of candidate genes for the biosynthesis of methyl hexanoate To understand the molecular basis of floral volatile biosynthesis in V. cruziana, an RNA-Seq library using the RNA samples of whole flowers of V. cruziana at full blooming stage was constructed and sequenced. High quality sequencing data was obtained, and the clean bases of flower and leaf were 6.11 G (Table S1). The de novo assembly yielded 64,472 unigenes (Table S1). The unigenes longer than 1k bp were 34483 that accounted for 53.49 % of the total unigenes and the N50 was 2476 bp (Table S1). More than 63.51 % unigenes were annotated in at least one database, and 16 % unigenes were annotated in all seven bioinformatics databases (Table S1). The annotated unigenes were clustered in three GO function classification (biological process, cellular component, molecular function, Fig. S1). Next, the transcriptome was specifically searched for candidate biosynthetic genes. This study focused on the biosynthesis of methyl hexanoate. Prior to this study, the biosynthesis of fatty acid methyl esters has been studied in another water lily N. colorata, in which methyl decanoate and methyl octanoate are biosynthesized by methyltransferases that belong to the SABATH family (Zhang et al., 2019). It was our hypothesis that the formation of methyl hexanoate in V. cruziana is also catalyzed by SABATH enzymes. As such, the flower transcriptome of V. cruziana was created (Fig. S1) and searched for SABATH genes. Three putative full-length SABATH genes were identified, which were designated as VcSABATH1, VcSABATH2 and VcSABATH3 with GenBank accession number of MZ541994, MZ541995 and MZ541996, respectively. The proteins they encode are 364 (VcSABATH1), 367 (VcSABATH2), and 362 (VcSABATH3) amino acids in length. Multiple sequence alignment revealed that all three VcSABATH proteins contain conserved residues for interacting with the carboxyl moiety of the substrate and the methyl donor S -adenosyl-L-methionine (Fig. 4). 2.5. Biochemical assay of VcSABATHs Next, in vitro methyltransferase enzyme assays were performed to determine which of the three VcSABATH genes is responsible for the biosynthesis of methyl hexanoate in V. cruziana flowers. A full-length cDNA for each of the three VcSABATH genes was synthesized and cloned into a protein expression vector (pET32a) and expressed in E. coil to produce recombinant enzymes. Individual recombinant VcSABATH proteins were tested in methyltransferase enzyme assays using hexanoic acid as substrate. While VcSABATH2 was inactive, both VcSABATH1 and VcSABATH3 catalyzed the formation of methyl hexanoate (Fig. 5). Next, E. coli -expressed recombinant VcSABATH1 and VcSABATH3 were purified (Fig. S2) and the purified proteins used to measure their respective specific activities. The specific activity of VcSABATH1 and VcSABATH3 using hexanoic acid as substrate was determined to be 23.2 ±2.41 pkat/mg protein and 150.4 ±3.6 pkat/mg protein, respectively. To determine substrate specificity of VcSABATH1 and VcSABATH3, they were also tested using three other fatty acids as substrate. The relative activity of VcSABATH1 using octanoic acid, decanoic acid or dodecanoic acid as substrate was 39.4 %, 33.6 % and 16.9 % of that with hexanoic acid respectively. Similarly, the relative activity of VcSABATH3 using octanoic acid, decanoic acid or dodecanoic acid as substrate was 33.5 %, 38.8 % and 17.3 % of that with hexanoic acid respectively. 2.6. Expression of VcSABATH1 and VcSABATH 3 in different flower organs With VcSABATH3 and VcSABATH1 demonstrated to encode hexanoic acid methyltransferase, their expression in different parts of V. cruziana flowers was measured using reverse transcriptionquantitative PCR (RT-qPCR). The highest level of expression of VcSABATH1 was detected in stamens (Fig. 6A), whereas VcSABATH3 showed the highest level of expression in pistils (Fig. 6B). 2.7. Phylogenetic analysis Prior to this study, the SABATH family of methyltransferases in plants has been relatively well studied with a number of members characterized (D’ Auria et al., 2003). These include salicylic acid MT (Ross et al., 1999; Chen et al., 2003, Zhao et al., 2010), jasmonic acid MT (Seo et al., 2001; Zhao et al., 2013), indole-3 acetic acid MT (Qin et al., 2005; Zhao et al., 2007, 2008), gibberellic acid MT (Varbanova et al., 2007; Zhang et al., 2020). To understand the evolutionary relatedness of the two fatty acid methyltransferases from V. cruziana (VcSABATH1 and VcSABATH3) with known SABATH proteins, phylogenetic analyses were performed. Three VcSABATHs form a water lily-specific cluster with 6 full-length SABATH members from N. colorata except the putative IAMT (Nc8G0124910-1) (Fig. 7). VcSABATH1 was most closely related to three NcSABATHs including Nc11G0120830-1 which was characterized to be decanoic acid methyltransferase (Zhang et al., 2019). VcSABATH2 and VcSABATH3 were most closely related to each other and together with two NcSABATHs of unknown functions they form a subcluster in water lily-specific cluster (Fig. 7).Published as part of Jiang, Yifan, Liu, Guanhua, Zhang, Wanbo, Zhang, Chi, Chen, Xinlu, Chen, Yuchu, Yu, Cuiwei, Yu, Dongbei, Fu, Jianyu & Chen, Feng, 2021, Biosynthesis and emission of methyl hexanoate, the major constituent of floral scent of a night-blooming water lily Victoria cruziana, pp. 1-10 in Phytochemistry (112899) (112899) 191 on pages 3-5, DOI: 10.1016/j.phytochem.2021.112899, http://zenodo.org/record/825821
Microscopic insights into CO₂-shale oil miscibility via interaction energy coupled with pore confinement: Implications for CO₂-enhanced oil recovery
No full textAs CO₂ injection can enhance the efficiency of shale oil extraction and reduce CO₂ emissions, it has been utilized widely in the development of shale oil resources. Minimum miscible pressure is an important parameter describing the miscibility of CO₂ and shale oil, which is of great importance for determination of CO₂ injection strategy. However, due to the unclear phase boundary caused by the confinement effect in shale nanopores, it is difficult to determine the minimum miscible pressure of CO₂ and shale oil. In this study, a new minimum miscible pressure estimation method is constructed, that is suitable for nanopores based on the significant co-evolution of pore wall adsorption and confined-bulk phase interactions. This method can mitigate the limitations of traditional minimum miscible pressure calculation methods relying on fluid interfaces. Furthermore, the confinement effects on the miscibility process are analyzed using a theoretical method and molecular dynamics simulation on the microscopic scale. The results demonstrate that the minimum miscible pressure of CO₂ and shale oil initially decreases as the pore size decreases. When the pore size decreases to a certain extent, the minimum miscible pressure increases with the thickness of the adsorbent layer rising and the CO₂ diffusion coefficient decreasing. Temperature elevation raises the minimum miscible pressure as it intensifies molecular thermal motion, weakens fluid adsorption, and reduces interaction energy, which are not conducive to miscibility. This study can provide an essential basis for the optimization of CO₂ injection pressure in shale oil reservoir development.Document Type: Original articleCited as: Yu, X., Dong, H., Li, Y., Liu, C., Zhang, L., Chen, Z. Microscopic insights into CO₂-shale oil miscibility via interaction energy coupled with pore confinement: Implications for CO₂-enhanced oil recovery. Advances in Geo-Energy Research, 2025, 17(2): 107-120. https://doi.org/10.46690/ager.2025.08.0
Xu shi yu shi jian: tan tao er shi shi ji xi fang xu shi xing hui hua de yan bian = Narrative and practice : the exploration of the narrative painting in the twentieth century.
No full text曾翠薇."2003年12月".論文(哲學碩士)--香港中文大學, 2003.參考文獻 (leaves 71-74).附中英文摘要."2003 nian 12 yue".Zeng Cuiwei.Lun wen (zhe xue shuo shi)--Xianggang Zhong wen da xue, 2003.Can kao wen xian (leaves 71-74).Fu Zhong Ying wen zhai yao.Chapter 第一章- --- 緒論Chapter 第一節： --- 何謂敘事 --- p.1-2Chapter 第二節： --- 敘事與人生的實踐 --- p.2-7Chapter 第二章- --- 西方敘事性繪畫的釋義及演變Chapter 第一節： --- 敘事性繪畫的定義 --- p.7-8Chapter 第二節： --- 二十世紀現代藝術的敘事性繪畫Chapter 2.1 --- 現代藝術的文化背景 --- p.8-9Chapter 2.2 --- 敘事性繪畫在現代藝術中的發展狀況Chapter 2.2.1 --- 表現主義繪畫的個體表述 --- p.10-12Chapter 2.2.2 --- 超現實主義繪畫的敘事手法 --- p.12-14Chapter 第三節： --- 當代敘事性繪畫的面貌Chapter 3.1 --- 當代藝術的敘事方式 --- p.14-16Chapter 3.2 --- 二十世紀末的敘事性繪畫 --- p.16-17Chapter 3.3 --- “新表現´ح和“超前衛´ح --- p.17-21Chapter 3.4 --- “新意象´ح與“塗鴉´ح --- p.21-23Chapter 第三章- --- 「新繪畫」與當代藝術的關係及其時代意義Chapter 第一節： --- 二十世紀下旬藝術的發展形勢 --- p.23-26Chapter 第二節： --- 「新繪畫」的作品特徵與後現代文化之關係Chapter 2.1 --- 隱喻和象徵 --- p.26-27Chapter 2.2 --- 神話與寓言 --- p.27-30Chapter 2.3 --- 原始和本能 --- p.31-32Chapter 2.4 --- 反諷與拼貼 --- p.32-34Chapter 第三節： --- 繪畫的復興的時代訊息Chapter 3.1 --- 反省精神 --- p.34Chapter 3.2 --- 形象的回歸 --- p.34-35Chapter 3.3 --- 敘事性和文學性重新被肯定 --- p.35Chapter 第四章- --- 探討繪畫中「真實」意涵的演變Chapter 第一節： --- 繪畫中「真實」意涵的演變Chapter 1.1 --- 再現的真實 --- p.36-40Chapter 1.2 --- 真實與表現性 --- p.40Chapter 1.3 --- 個體內在的真實 --- p.40-41Chapter 1.4 --- 原始、本能與真實 --- p.42Chapter 1.5 --- 後現代中的真實 --- p.43-46Chapter 第二節： --- 在敘事性繪畫中追逐「真實」的意涵 --- p.46-49Chapter 第五章- --- 結論 --- p.49-5
