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Investigation of migration of pollutant at the base of Suzhou Qizishan landfill without a liner system

Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第3期10卷 439-449页

作者： hai-jian XIE Yun-min chen Liang-tong ZHAN Ren-peng chen Xiao-wu TANG ru-hai chen Han KE MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang University Hangzhou 310058 China College of Civil Engineering and Architeeture Zhejiang University Hangzhou 310058 China

We investigated migration of pollutant at the base of the Suzhou landfill after it had been operated for 13 years. The investigation was carried out by performing chemical analyses on the soil samples taken from the silty clay deposit. Concentrations of chloride, chemical oxygen demand （COD） and the heavy metals in the soil samples were determined using the standard methods. The experimental data showed that the maximum migration depth of chloride was more than 10 m, while the maximum migration depth of COD varied between 1 and 3.5 m. It is believed that the difference is attributed to the variation in diffusion rate and leachate-soil interaction. The chloride profiles also indicated that adveetion may be the dominant contaminant transport mechanism at this site. The total contents ofCu, Pb and Cr are very close to the background levels and the concentration values of these metals mainly are lower than the threshold values specified by the Chinese soil quality standard and the European one. The water-extractable concentrations of COD in the surface of the silty clay generally exceed the limit value specified by the Chinese standard. The concentrations of copper and chromium in pore water are 1-2 orders of magnitude less than the total concentrations of these heavy metals within the soils, implying that heavy metals are mainly adsorbed by the soil particles. Finally, remediation methods were suggested for this landfill site.

关键词： Uncontrolled landfill Field investigation Contaminant migration Soil contamination Heavy metals Organic contaminants Chloride

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链霉菌SC120细胞毒活性代谢产物的研究

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微生物学通报 2003年第1期30卷 19-22页

作者：王继栋魏孝义朱西儒谢海辉陈贻竹中国科学院华南植物研究所广州510650

在研究链霉菌Streptomycessp SC1 2 0抗荔枝霜疫霉菌活性代谢产物的过程中 ,分离得到一对人鼻咽癌细胞具有细胞毒作用的抗生素。通过UV、IR、HR MS、 1H NMR、13C NMR、DEPT、1H 1HCOSY、HMQC、HMBC等波谱分析 ,鉴定其结构与Pimprinine... 详细信息

在研究链霉菌Streptomycessp SC1 2 0抗荔枝霜疫霉菌活性代谢产物的过程中 ,分离得到一对人鼻咽癌细胞具有细胞毒作用的抗生素。通过UV、IR、HR MS、 1H NMR、13C NMR、DEPT、1H 1HCOSY、HMQC、HMBC等波谱分析 ,鉴定其结构与Pimprinine相同。

关键词：抗生素链霉菌 Pimprinine 细胞毒作用

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亲水作用液相色谱法同时测定美白化妆品中的α-熊果苷和β-熊果苷

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香料香精化妆品 2017年第6期 35-38页

作者：简龙海茹歌陈丹丹郑荣王柯上海市食品药品检验所上海201203

采用亲水作用液相色谱法同时测定美白化妆品中α-熊果苷和β-熊果苷的含量。样品经乙腈提取,用色谱柱Waters UPLC BEH Amide柱(100 mm×2.1 mm×1.7μm)分析。流动相为乙腈-水(体积比93︰7)。流速为0.3 m L/min。采用荧光检测器,激发波... 详细信息

采用亲水作用液相色谱法同时测定美白化妆品中α-熊果苷和β-熊果苷的含量。样品经乙腈提取,用色谱柱Waters UPLC BEH Amide柱(100 mm×2.1 mm×1.7μm)分析。流动相为乙腈-水(体积比93︰7)。流速为0.3 m L/min。采用荧光检测器,激发波长为283 nm,发射波长为330 nm。α-熊果苷、β-熊果苷响应值均在2~2 000 ng/m L范围内线性关系良好(r>0.999);在霜类、乳液类、水剂类3种化妆品空白基质中,α-熊果苷、β-熊果苷的添加水平为0.05、1.00和20.00μg/g时,平均回收率在91.5%~96.5%之间(n=6,相对标准偏差≤6.1%)。定量下限均为0.05μg/g。本方法简便、快速、灵敏,可用于美白化妆品中α-熊果苷、β-熊果苷的同时定量测定。

关键词：亲水作用色谱 α-熊果苷 β-熊果苷化妆品美白成分

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An improvement of chen-ru-Yan's degenerated second main theorem

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Science China Mathematics 2015年第12期58卷 2517-2530页

作者： SHI Lei ru Min Department of Mathematics East China Normal University Department of Mathematics University of Houston

We give an improvement for the second main theorem of algebraically non-degenerate holomorphic curves into a complex projective variety V intersecting hypersurfaces in subgeneral position, obtained by chen et al.(2012... 详细信息

关键词： Nevanlinna theory holomorphic curve second main theorem truncation level

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Transcriptional memory of different types of genes is generally maintained under various environmental conditions in Saccharomyces cerevisiae

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Journal of Genetics and Genomics 2022年第2期49卷 173-176页

作者： ru-Xin Wang Yu-Min Li runfa chen hai-Ning Du Hubei Key Laboratory of Cell Homeostasis RNA InstituteCollege of Life SciencesWuhan UniversityWuhan 430072China

When certain genes are exposed to repeated stimuli, they can be rapidly reactivated after prior expression and show enhanced expression signals, known as transcriptional memory. Such reinduction memory of gene expression is an essential adaptation to the recurring environmental changes, which facilitates divergent organisms evolve the capacity to reduce the need for genetic fitness(New et al., 2014).

关键词： maintained evolve

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Investigating the Absorption and Desorption Behavior of Methylene Chloride in the Poly(aryl ether ketone) Film with Different Crystallinities

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Chinese Journal of Polymer Science 2024年第2期42卷 239-246,I0009页

作者： Hong-ru Yang Jin-Dong Zhang Dong-Ting Gao Gang Liu Chun-hai chen Jia-Nan Yao Center for Advanced Low-Dimension Materials State Key Laboratory for Modification of Chemical Fibers and Polymer MaterialsCollege of Materials Science and EngineeringDonghua UniversityShanghai201620China

Poly(aryl ether keton e)(PAEK) films with different crystallinities were obtained by controlling the cooling rate,which were subjected to the absorption and desorption of methylene chloride(CH_(2)Cl_(2)).We employed attenuated total reflection Fourier transform infrared(ATR-FTIR)spectroscopy analyses to investigate the diffusion behavior of CH_(2)Cl_(2) in PAEK films with different *** to the Fickian diffusion model,the calculated diffu sion coefficients of CH_(2)Cl_(2) in PAEK films were observed to decrease with increasing *** effect of CH_(2)Cl_(2)absorption and desorption on the mechanical properties of PAEK films with different crystallinity was further analyzed using tensile *** tensile tests exhibited that CH_(2)Cl_(2) has two concurrent effects:plasticization and solvent-induced *** scanning calorimetry(DSC) and wide-angle X-ray diffraction(WXRD) techniques further confirmed solvent-induced crystallization *** results would be beneficial to understand the solvent resistance of PAEK materials and consequently provide the practical application conditions of PAEK with a theoretical basis.

关键词： Poly(aryl ether ketone) Diffusion behavior Infrared spectra Solvent-induced crystallization Mechanical properties

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PTEN knockdown with the Y444F mutant AAV2 vector promotes axonal regeneration in the adult optic nerve

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Neural Regeneration Research 2018年第1期13卷 135-144页

作者： Zheng-ru Huang hai-ying chen Zi-zhong Hu Ping Xie Qing-huai Liu Department of Ophthalmology the First Affiliated Hospital of Nanjing Medical University Nanjing Jiangsu Province China Department of Ophthalmology the Second People's Hospital of Changshu Changshu Jiangsu Province China

The lack of axonal regeneration is the major cause of vision loss after optic nerve injury in adult mammals. Activating the PI3K/AKT/mTOR signaling pathway has been shown to enhance the intrinsic growth capacity of neurons and to facilitate axonal regeneration in the central nervous system after injury. The deletion of the mTOR negative regulator phosphatase and tensin homolog （PTEN） enhances regeneration of adult corticospinal neurons and ganglion cells. In the present study, we used a tyrosine-mutated （Y444F） AAV2 vector to efficiently express a short hairpin RNA （shRNA） for silencing PTEN expression in retinal ganglion cells. We evaluated cell survival and axonal regeneration in a rat model of optic nerve axotomy. The rats received an intravitreal injection of wildtype AAV2 or Y444F mutant AAV2 （both carrying shRNA to PTEN） 4 weeks before optic nerve axotomy. Compared with the wildtype AAV2 vector, the Y444F mutant AAV2 vector enhanced retinal ganglia cell survival and stimulated axonal regeneration to a greater extent 6 weeks after axotomy. Moreover,post-axotomy injection of the Y444F AAV2 vector expressing the shRNA to PTEN rescued ～19% of retinal ganglion cells and induced axons to regenerate near to the optic chiasm. Taken together, our results demonstrate that PTEN knockdown with the Y444F AAV2 vector promotes retinal ganglion cell survival and stimulates long-distance axonal regeneration after optic nerve axotomy. Therefore, the Y444F AAV2 vector might be a promising gene therapy tool for treating optic nerve injury.

关键词： nerve regeneration optic nerve axotomy gene therapy Müller cell retinal ganglion cell AAV2 shRNA PTEN GLAST mTOR neural regeneration

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Optimizations for High Performance Network Virtualization

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Journal of Computer Science & Technology 2016年第1期31卷 107-116页

作者： Fan-Fu Zhou ru-Hui Ma Jian Li Li-Xia chen Wei-Dong Qiu hai-Bing Guan Shanghai Key Laboratory of Scalable Computing and Systems Shanghai Jiao Tong University Shanghai 200240 China

The increasing requirements of intensive interoperaterbility among the distributed nodes desiderate the high performance network connections, owing to the substantial growth of cloud computing and datacenters. Network I/O virtualization aggregates the network resource and separates it into manageable parts for particular servers or devices, which provides effective consolidation and elastic management with high agility, flexibility and scalability as well as reduced cost and cabling. However, both network I/O virtualization aggregation and the increasing network speed incur higher traffic density, which generates a heavy system stress for I/O data moving and I/O event processing. Consequently, many researchers have dedicated to enhancing the system performance and alleviating the system overhead for high performance networking virtualizatiou. This paper first elaborates the mainstreaming I/O virtualization methodologies, including device emulation, split-driver model and hardware assisted model. Then, the paper discusses and compares their specific advantages in addition to performance bottlenecks in practical utilities. This paper mainly focuses on the comprehensive survey of state- of-the-art approaches for performance optimizations and improvements as well as the portability management for network I/O virtualization. The approaches include various novel data delivery schemes, overhead mitigations for interrupt processing and adequate resource allocations for dynamic network states. Finally, we highlight the diversity of I/O virtualization besides the performance improvements in network virtualization infrastructure.

关键词： network virtualization single root I/O virtualization (SR-IOV) virtual machine monitor (VMM)

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nfluences of superheat and cooling intensity on macrostructure and macrosegregation of duplex stainless steel studied by thermal simulation

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Journal of Iron and Steel Research International 2021年第9期28卷 1125-1132页

作者： Hong-gang Zhong Xiang-ru chen Yan-jie Liu Zhi-qiang Wei hai-feng Yu Qi-jie Zhai Center for Advanced Solidification Technology Shanghai UniversityShanghai200444China Shanghai Institute of Materials Genome Shanghai200444China Research Institute Baoshan Iron&Steel Co.Ltd.Shanghai200431China

The influences of superheat and cooling intensity on macrostructure and macrosegregation of one new kind duplex stainless steel(DSS)were *** simulation equipment was applied to prepare samples,which could reproduce the industrial processes of DSS manufactured by a vertical continuous slab *** and macrosegregation were analyzed using the digital single lens reflex and laser-induced breakdown spectroscope(LIBSOPA-200),*** percentage of both chill zone and center equiaxed zone increases with the superheat decreasing,while that of the columnar zone *** is only equiaxed grain existing as the superheat is 10 and 20℃.The lower the superheat is,the coarser the gain size *** cooling intensity in mold could remarkably decrease the chill zone length and refine the grains in chill zone and center equiaxed *** influences of cooling intensity on macrosegregation are greater than those of *** macrosegregation of Si,Mn and Cr is slightly dependent on superheat,while that of Cu,Mo and Ni changes greatly with superheat increasing.

关键词： Continuous casting Solidification Thermal simulation Duplex stainless steel Macrosegregation

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Cloning and Characterization of WOX4 Gene from Vitis vinifera L. Involved in Stem Cell Regulation

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Agricultural Sciences in China 2011年第12期10卷 1861-1871页

作者： DAI ru JIN hai-peng WANG Zeng Avihai Perl XU hai-ying ZHANG Wen chen Shang-wu MA Hui-qin College of Agriculture and Biotechnology China Agricultural University Beijing 100193 P.R. China Department of Fruit Tree Breeding and Molecular Genetics Agricultural Research Organization Bet-Dagan 50250 Israel Institute of Forestry and Fruit Tree Sciences Beijing Academy of Agricultural Sciences Beijing 100093 P.R. China Key Lab of Functional Dairy Science Ministry of Education of China Municipal Government of Beijing/College of Food Science and Nutritional Engineering China Agricultural University Beijing 100083 P.R. China

Wuschel-related homeobox （WOX） genes play essential, specific, and sometimes redundant roles in plant embryo development, shoot and root meristem maintenance, and plant development. Though much information was quickly gained with members of the WOX gene family of Arabidopsis, monocotyledonous crops, and gymnospermous conifers, little is known about perennial woody plants. In this study, we isolated the first WOXgene family member from grape （Vitis vinifera L. cv. Cabernet Sauvignon）, and named it VvWOX4 based on its characteristic domains and phylogenetic analysis. The identity of VvWOX4 was validated by MALDI-TOF MS and Western blot with polyclonal antibody against Arabidopsis thaliana Wuschel. Functional analysis showed that VvWOX4 markedly increased shoot primordia structures when overexpressed under CaMV 35S promoter in tobacco. A different expression pattern was found for VvVOX4 compared with AtWUCHEL and its expression was detected in unique organs of grapevines. Besides the expression in the vegetative shoot apical meristem （SAM） of grape shoot tips, VvWOX4 is expressed in dormant winter buds, inflorescence, young leaves, and tendril tips, but not in root tips. In young leaves, the expression of VvWOX4 is strongly upregulated by wounding, and also by plant growth regulators such as 2 mg L-1 2,4-D, 1 mg L-1 NAA and 1 mg L-1 BAP treatments, while downregulation was monitored by 1 mg L^-1 IBA treatment, and there was no response to 0.5 mg L-1 GA3 treatment. Together, our results revealed the first member of grape WOX gene family and indicated different roles and regulation of VvWOX4 in the perennial woody crop grapevine.

关键词： expression characteristics gene cloning plant hormone induced expression Htis vinifera L. WOX4

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