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Journal of Integrative Agriculture 2016年第9期15卷 1968-1982页

作者： wang yan-nan LI yan ZHANG Huan ZHAI Hong LIU Qing-chang HE Shao-zhen College of Agronomy & Biotechnology China Agricultural University

A plastidic adenosine triphosphate（ATP）/adenosine diphosphate（ADP） transporter（AATP） is responsible for importing ATP from the cytosol into plastids. In dicotyledonous plants, increasing ATP supply is a potential way to facilitate anabolic synthesis in heterotrophic plastids. In this study, a gene encoding the AATP protein, named Ib AATP, was isolated from sweetpotato（Ipomoea batatas（L.） Lam.）. Transcripts of Ib AATP were predominantly detected in the storage roots and leaves and were induced by exogenous sucrose and subjected to circadian rhythm. Transient expression of Ib AATP in tobacco and onion epidermal cells revealed the plastidic localization of Ib AATP. The overexpression of Ib AATP in sweetpotato significantly increased the starch and amylose contents and led to enlarged starch granules. The IbA ATP-overexpressing plants showed altered fine structure of amylopectin, which contained an increased proportion of chains with a degree of polymerization（DP） of 10–23 and a reduced number of chains with a DP of 5–9 and 24–40. In addition, starch from the transgenic plants exhibited different pasting properties. The transcript levels of starch biosynthetic genes, including Ib AGP, Ib GBSSI, Ib SSIIV, and Ib SBE, were differentially regulated in the transgenic plants. These results revealed the explicit role of Ib AATP in the starch biosynthesis of sweetpotato and indicated that this gene has the potential to be used to improve starch content and quality in sweetpotato and other plants.

关键词： sweetpotato Ib AATP starch content and composition starch granule size starch structure pasting properties

Doebner condensation in ionic liquids [Bmim]BF_4 and [Bpy]BF_4 to synthesize α,β-unsaturated carboxylic acid

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Chinese Chemical Letters 2009年第3期20卷 279-282页

作者： Dong Jiang Yuan Yuan wang yan nan Xu Li Yi Dai Shanghai Key Laboratory of Green Chemistry and Chemical Processes Department of Chemistry East China Normal University Shanghai 200062 China

Ionic liquids [Bmim]BF4 and [Bpy]BF4 were employed as environmentally benign media in Doebner condensation to synthesize α, β-unsaturated carboxylic acid. The good results showed that [Bmim]BF4 and [Bpy]BF4 were efficient media for Doebner condensation, which could be recycled easily. The highest yields could reach 93% and 90% in [Bmim]BF4 and [Bpy]BF4, respectively.

关键词： Ionic liquid Doebner condensation α, β-Unsaturated carboxylic acid Decarboxylation

Characterization of salt tolerance and Fusarium wilt resistance of a sweetpotato mutant

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Journal of Integrative Agriculture 2017年第9期16卷 1946-1955页

作者： ZHANG Huan ZHANG Qian wang yan-nan LI yan ZHAI Hong LIU Qing-chang HE Shao-zhen Key Laboratory of Sweetpotato Biology and Biotechnology Ministry of Agriculture/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop He terosis and UtilizationMinistry of Education/China Agricultural UniversityBeijing 100193P.R.China

The variant LM1 was previously obtained using embryogenic cell suspension cultures of sweetpotato variety Lizixiang by gamma-ray induced mutation, and then its characteristics were stably inherited through six clonal generations, thus this mutant was named LM1. In this study, systematic characterization of salt tolerance and Fusarium wilt resistance were performed between Lizixiang and mutant LM1. LM1 exhibited significantly higher salt tolerance compared to Lizixiang. The content of proline and activities of superoxide dismutase（SOD） and photosynthesis were significantly increased, while malonaldehyde（MDA） and H_2O_2 contents were significantly decreased compared to that of Lizixiang under salt stress. The inoculation test with Fusarium wilt showed that its Fusarium wilt resistance was also improved. The lignin, total phenolic, jasmonic acid（JA） contents and SOD activity were significantly higher, while H_2O_2 content was significantly lower in LM1 than that in Lizixiang. The expression level of salt stress-responsive and disease resistance-related genes was significantly higher in LM1 than that in Lizixiang under salt and Fusarium wilt stresses, respectively. This result provides a novel and valuable material for improving the salt tolerance and Fusarium wilt resistance of sweetpotato.

关键词： Fusarium wilt resistance mutant salt tolerance sweetpotato

Molecular Cloning and Functional Characterization of a Salt Tolerance-Associated Gene IbNFU1 from Sweetpotato

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Journal of Integrative Agriculture 2013年第1期12卷 27-35页

作者： wang Lian-jun HE Shao-zhen ZHAI Hong LIU De-gao wang yan-nan LIU Qing-chang Key Laboratory of Crop Genomics and Genetic Improvement Ministry of Agriculture/Beijing Key Laboratory of Crop Genetic Improvement/Laboratory of Crop Heterosis and UtilizationMinistry of Education/China Agricultural University

Iron-sulfur cluster biosynthesis involving the nitrogen fixation（Nif） proteins has been proposed as a general mechanism acting in various ***-like protein may play an important role in protecting plants against abiotic and biotic *** on the EST sequence selected from salt-stressed suppression subtractive hybridization（SSH） cDNA library constructed with a salt-tolerant mutant LM79,a NFU gene,termed IbNFU1,was cloned from sweetpotato（Ipomoea batatas（L.） Lam.） via rapid amplification of cDNA ends（RACE）.The cDNA sequence of 1 117 bp contained an 846 bp open reading frame encoding a 281 amino acids polypeptide with a molecular weight of 30.5 kDa and an isoelectric point（pI） of ***1 gene contained a conserved Cys-X-X-Cys motif in C-terminal of the iron-sulfur cluster *** deduced amino acid sequence had 66.08 to 71.99% sequence identity to NFU genes reported in Arabidopsis thaliana,Eucalyptus grandis and Vitis ***-time quantitative PCR analysis revealed that the expression level of IbNFU1 gene was significantly higher in the roots of the mutant LM79 compared to the wild-type *** tobacco（*** 38） plants expressing IbNFU1 gene exhibited significantly higher salt tolerance compared to the untransformed control *** is proposed that IbNFU1 gene has an important function for salt tolerance of plants.

关键词： cloning IbNFU1 gene Ipomoea batatas(L.) Lam. salt tolerance

Vanadium extraction and dephosphorization from V-bearing hot metal with fluxes containing CaO

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Journal of Central South University 2015年第8期22卷 2887-2893页

作者：王艳南宋文臣李宏 State Key Laboratory of Advanced Metallurgy (University of Science and Technology Beijing) School of Metallurgical and Ecological Engineering University of Science and Technology Beijing

Extracting vanadium and removing phosphorus simultaneously by adding CaO containing materials to V-bearing hot metal were investigated under the condition of simulating the process of vanadium extraction with insufficiently supplying oxygen in converter. Through preliminary experiments, 3 h and 1375 °C were chosen as the optimum holding time and reaction temperature for formal experiments, respectively. The results of the formal experiments suggest that making basic slag can extract vanadium and remove phosphorus simultaneously. The vanadium extraction rate(ηV) and phosphorus removal rate(ηP) both increase with an increase in the basicity of the original slag materials and the Fe2O3 contents. The vanadium distribution ratio)(V L′is about an order of magnitude greater than the phosphorus distribution ratio),(P L′but the latter is more sensitive to slag basicity than the former. The phosphorus distribution ratio is beyond 6 when the basicity of the original slag materials is beyond 1, which indicates a much better performance of phosphorus removal compared to the phosphorus removal in the current process. Therefore, it is very feasible to properly raise slag basicity to remove phosphorus with consideration of the grade of vanadium slag. The relations between ηV and ηP, and between L′V and L′P are linear under the experimental conditions.

关键词： vanadium extraction phosphorus removal basicity vanadium distribution ratio phosphorus distribution ratio

Automated Contour Detection for Intravascular Ultrasound Image Sequences Based on Fast Active Contour Algorithm

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Chinese Journal of Biomedical Engineering(English Edition) 2006年第1期15卷 16-25页

作者： DONG Hai-yan wang Hui-nan College of Automation Engineering Nanjing University of Aeronautics & Astronautics Nanjing 210016 China College of Automation EngineeringNanjing University of Aeronautics & Astronautics Nanjing 210016 China

Intravascular ultrasound can provide high-resolution real-time cross-sectional images about lumen, plaque and tissue. Traditionally, the luminal border and medial-adventitial border are traced manually. This process is extremely time-consuming and the subjective difference would be large. In this paper, a new automated contour detection method is introduced based on fast active contour model. Experimental results found that lumen and vessel area measurements after automated detection showed good agreement with manual tracings with high correlation coefficients (0.94 and 0.95, respectively) and small system difference (-0.32 and 0.56, respectively). So it can be a reliable and accurate diagnostic tool.

关键词： Intravascular ultrasound, Active contour, Contour detection, Luminal border, Medial-adventitial border

A new approach to the synthesis of diacetals(diketals) pentaerythritol catalyzed by SO_3H-functionalized ionic liquids

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Chinese Chemical Letters 2010年第5期21卷 524-528页

作者： Yuan Yuan wang,yan nan Xu,Zhi Zhong wang,Li Yi Dai Shanghai Key Laboratory of Green Chemistry and Chemical Process,Department of Chemistry, East China Normal University,Shanghai 200062,China [a] Shanghai Key Laboratory of Green Chemistry Chemical Process Department of Chemistry East China Normal University Shanghai 200062 China

In this article,an efficient,simple and environmentally friendly approach to the synthesis of diacetals(diketals) pentaerythritol using SOH-functionalized ionic liquids(ILs) as catalysts was *** ILs show high catalytic activity and reusability with good to excellent yields of the desired *** method has been used to determine the acidity order of these ionic liquids and the results are consistent with the catalytic activities observed in acetalization *** product yield of 93%was observed on using[PSPy][OTf]as catalyst and it can be reused at least 8 times without obvious activity loss.

关键词： SO3H-functionalized ionic liquids Diacetals(diketals) pentaerythritol Catalyze Hammett method Reusability

变形链球菌侵袭对4种复合树脂粘结界面老化的影响

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口腔医学研究 2016年第1期32卷 83-86页

作者：王南燕佛山市第一人民医院口腔科广东佛山528000

目的:探讨变形链球菌侵袭对4种复合树脂粘结界面老化的影响。方法:选取2种大块充填复合树脂和2种传统复合树脂,将4种复合树脂材料试件浸入菌液内孵育14d,之后对试件进行超声清洗,在体视显微镜下观察粘结面裂隙面积占总粘结面积的百分比... 详细信息

目的:探讨变形链球菌侵袭对4种复合树脂粘结界面老化的影响。方法:选取2种大块充填复合树脂和2种传统复合树脂,将4种复合树脂材料试件浸入菌液内孵育14d,之后对试件进行超声清洗,在体视显微镜下观察粘结面裂隙面积占总粘结面积的百分比,以了解粘结表面破坏情况;在每组中选取2个样本,使用离子溅射仪喷金,喷金后的标本用导电胶固定在标本台上,用扫描电镜观察对比4种材料粘结面破坏情况。结果:4种复合树脂在变形链球菌侵袭下具有不同形式的破坏,粘结破坏程度各组之间不存在显著差异,SDR对应的级别平均值最大,Z350稍微大于P60和Tetric N-Ceram Bulk Fill;P60与Tetric N-Ceram Bulk Fill,粘结面破坏均位于粘结面与牙本质间,树脂Z350和SDR裂隙产生在粘结面与树脂间。结论:变形链球菌在短期内可破坏复合树脂表面及粘结界面,成分不同破坏方式不同,破坏程度没有显著差异。

关键词：复合树脂粘结界面抗菌能力变形链球菌

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不同复合树脂材料硬度及黏结强度的比较

中国组织工程研究 2015年第47期19卷 7639-7643页

作者：王南燕张辉燕佛山市第一人民医院口腔科广东省佛山市528000

背景:与传统复合树脂材料相比,大块充填复合树脂材料具有增加光固化深度、降低聚合收缩率、简化临床操作程序等特点,但不同类型大块充填复合树脂材料的性能各异。目的:分析4种复合树脂材料的硬度及黏结强度。方法:取大块填充复合树脂Tet... 详细信息

背景:与传统复合树脂材料相比,大块充填复合树脂材料具有增加光固化深度、降低聚合收缩率、简化临床操作程序等特点,但不同类型大块充填复合树脂材料的性能各异。目的:分析4种复合树脂材料的硬度及黏结强度。方法:取大块填充复合树脂Tetric Evo Ceram Bulk Fill、SDR,以及传统复合树脂P60、Z350,检测4种复合树脂材料分别在2,3,4,5 mm光固化深度下的维氏显微硬度,以及4种复合树脂材料与牙本质间的剪切黏结强度。结果与结论:不同光固化深度下的硬度顺序为:P60复合树脂>Z350复合树脂>Tetric Evo Ceram Bulk Fill复合树脂>SDR复合树脂,4组间比较差异有显著性意义(P<0.05);Tetric Evo Ceram Bulk Filll和SDR复合树脂光固化后的硬度未随着固化深度的增加而明显减小。Tetric Evo Cream Bulk Fil和SDR复合树脂的剪切黏结强度显著高于P60和Z350复合树脂(P<0.05)。表明大块充填树脂材料Tetric Evo Ceram Bulk Fill和SDR的综合机械性能较高,并且具有较高的剪切黏结强度。

关键词：生物材料口腔生物材料复合树脂固化深度黏结强度硬度

改进VMD及其在时变结构地震响应瞬时频率识别中的应用

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振动工程学报 2024年第3期37卷 402-413页

作者：王焱楠尚旭强黄天立中南大学土木工程学院湖南长沙410075

强地震动作用下,结构动力特性因损伤将随时间变化,变分模态分解(Variational Mode Decomposition,VMD)可用于分析结构地震响应的瞬时频率变化规律,揭示地震过程中结构的损伤状态。针对人为预设分解模态数K和二次惩罚因子α参数不准确导... 详细信息

强地震动作用下,结构动力特性因损伤将随时间变化,变分模态分解(Variational Mode Decomposition,VMD)可用于分析结构地震响应的瞬时频率变化规律,揭示地震过程中结构的损伤状态。针对人为预设分解模态数K和二次惩罚因子α参数不准确导致VMD非平稳响应出现模态混叠的问题,提出了一种改进的VMD(Improved VMD,IVMD)算法,结合Hilbert变换(HT)可准确识别非平稳地震激励下时变结构的瞬时频率。采用多重信号分类(Multiple Signal Classification,MUSIC)算法确定分解模态数K,基于整体正交系数和能量比系数构建综合目标函数,并采用樽海鞘算法(Slap Swarm Algorithm,SSA)优化确定二次惩罚因子。在优化确定K和α参数的基础上,结合IVMD和HT识别时变结构地震响应瞬时频率。典型模拟信号和地震激励下4层时变框架结构数值模拟响应表明,相比VMD算法,IVMD算法识别得到的瞬时频率精度更高;12层钢筋混凝土框架结构模型地震模拟振动台试验数据验证了所提方法的实用性。

关键词：地震激励时变框架结构振动台试验瞬时频率识别变分模态分解