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Intraspecific differences in effects of co-contamination of cadmium and arsenate on early seedling growth and metal uptake by wheat

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Journal of Environmental Sciences 2007年第10期19卷 1221-1227页

作者： liu xiao-li ZHANG Shu-zhen State Key Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

A hydroponic experiment was carried out to study intraspecific differences in the effects of different concentrations of cadmium （Cd）（0-10 mg/L） and arsenate （As（V））（0-8 mg/L） on the growth parameters and accumulation of Cd and As in six wheat varieties Jing- 9428, Duokang- 1, Jingdong- 11, Jing-411, Jingdong-8 and Zhongrnai-8. The endpoints of wheat seedlings, including seed germination, biomass, root length and shoot height, decreased with increasing the Cd and As concentrations. Significant differences in seed germination, biomass, root length, shoot height and the accumulation of Cd and As were observed between the treatments and among the varieties （p 〈 0.05）. The lethal dosage 50% were about 20, 80, 60, 60, 80 and 20 mg As/L for Jing-9428, Duokang-1, Jingdong-11, Jing-411, Jingdong-8 and Zhongrnai-8, respectively, and the corresponding values for Cd were about 30, 80, 20, 40, 60 and 10 mg Cd/L, respectively. Among the six varieties, Duokang-1 was found to be the most resistant to Cd and As toxicity, and Zhongrnai-8 was the most sensitive to Cd and As co-contamination. The resistance of the six varieties was found dependant on the seedling uptake of Cd and As. Duokang-1 was the most suitable for cultivation in Cd and As co-contaminated soils.

关键词： Cd As varieties co-contamination wheat seedling

POLY(MALEIC ANHYDRIDE-CO-ACRYliC ACID)/POLY(ETHYLENE GLYCOL)HYDROGELS WITH pH- AND IONIC-STRENGTH-RESPONSES

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Chinese Journal of Polymer Science 2010年第6期28卷 951-959页

作者： Meng Yang Bo-tian liu Ge Gao xiao-li liu Feng-qi liu College of Chemistry and Macdiarmid Laboratory Jilin University Changchun 130012 China

Poly（maleic anhydride-coacrylic acid）,P（MA-AA）,was synthesized by the free-radical copolymerization of maleic anhydride with acrylic acid,and fast responsive pH-sensitive poly（maleic anhydride-co-acrylic acid）/polyethylene glycol,P（MA-AA）/PEG,hydrogels were prepared using PEG as macromolecular cross-linking ***-IR and ~1H-NMR spectrometry were applied to characterize the structure of P（MA-AA）.The influences of pH and ionic strength on the swelling behavior of P（MA-AA）/PEG hydrogels and the swelling-deswelling changes along with the repeated changes between acid and alkali conditions were *** results showed that there was a hundredfold difference in the swelling ratios between the conditions of acid and alkali,and the swelling capability could not be weakened after multiple swelling-deswelling *** results of swelling kinetics demonstrated that the response rate of P（MA-AA）/PEG hydrogels was very fast,because the swelling transition points always occurred at 10 *** pH-responsive hydrogels reported here might be a smart material for potentially applications in many areas,including biosensors,drug-delivery devices and tissue engineering.

关键词： pH-response P(MA-AA) Macromolecular cross-linking agent External cross-linking

A new trimeric furanocoumarin from Heracleum rapula

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Chinese Chemical Letters 2009年第9期20卷 1088-1090页

作者： Cun Zhang YuanYan liu Yong Qing xiao li li Institute of Chinese Materia Medica China Academy of Traditional Chinese Medicine Beijing 100700 China

A new trimeric linear-type furanocoumarin, rapultririn A （1）, was isolated from the underground part ofHeracleum rapula. The structure of this new compound was elucidated by NMR, MS spectroscopic methods. 2009 Yon... 详细信息

关键词： Heracleum rapula Tricoumarin Rapultririn A

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Biomedical and Environmental Sciences 2021年第4期34卷 324-329页

作者： liu xiao Bing WANG Jun li Ya Jie TAN Hong Xing liu Yan Yan YU Wei ZHANG Yu YANG li Chen PIAO Jian Hua liu xiao li YANG xiao Guang Shenzhen Center for Chronic Disease Control Shenzhen 518020GuangdongChina Key Laboratory of Trace Element Nutrition of National Health Commission National Institute of Nutrition and HealthChinese Center for Disease Control and PreventionBeijing 100050China Changzhi Medical College Changzhi 047500ShanxiChina

Iodine is an essential component of thyroid hormones’biosynthesis and is crucial for normal growth and healthy development[1].If the amount of dietary iodine intake cannot match the long-term requirement,regardless of whether it is excessively low or high,it can cause various thyroid dysfunctions,including hyperthyroidism,hypothyroidism,and autoimmune thyroid diseases[2].

关键词： intake diseases dietary

Solvent Effect on Conformation of a Cycloheptapeptide,Stylopeptide 1,Evaluated by Molecular Dynamics in Methonal and Aqueous Environments

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Chemical Research in Chinese Universities 2009年第4期25卷 560-563页

作者： liu xiao-qing li xiao-hui TENG Hu XIU Zhi-long Department of Bioscience and Biotechnology School of Environmental and Biological Science and Technology Dalian University of Technology Dalian 116024 P. R. China

Stylopeptide 1 synthesized and isolated from different sources exhibits a large activity difference in inhibitory effect on the growth of a cancer *** on the different amounts of methanol and water during synthesis,isolation and purification of the cyclic peptides,molecular dynamics(MD) was employed to simulate the conformation of stylopeptide 1 in methanol and aqueous *** comparative results show that the backbone ring was more rigid in methanol than in *** methanol,two β-turns and three hydrogen bonds were well conserved throughout the simulation,whereas no hydrogen bonds or turns were preserved in *** activity difference of stylopeptide 1 seemed to be attributed to the solvent effect on its conformation.

关键词： Cyclic peptide Methanol Water Molecular dynamics

The Effects of Different Tillages on Crop Residue Sequestration, Soil Available Nutrients and Some Biochemical Properties in the Chinese Black Soil Region

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Agricultural Sciences in China 2011年第4期10卷 576-584页

作者： liu xiao-li CHEN Qiu-wen ZENG Zhao-xia State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 P.R.China Key Laboratory of Agro-Ecology Institute of Subtropical Agriculture Chinese Academy of Sciences Changsha 410125 P.R.China College of Resources ＆ Environment Hunan Agricultural University Changsha 410128 P.R.China

Three-year field experiments were conducted to investigate the effects of different tillage operations after harvest on crop residues sequestration and their subsequent effects on soil available nitrogen （N）, phosphorus （P）, some soil biochemical properties, and three enzymatic activities during the following growing seasons in a soybean （Glycine max）-soybean- corn （Zea mays） rotation farming system in Northeast China. Two different managements were implemented after crop harvest every year, which were tillage （T） and no tillage （NT）. Results showed that crop residue masses on soil surface and in the 0-20 cm layer after soybean harvest were about 1 450 and 340 kg ha-1, respectively, in October 2006 and 2007. While, soybean residue mass in the 0-20 cm soil layer was about 340 kg ha-1 in NT and about 1 550 kg ha-1 in T before sowing in May 2007 and 2008. The adverse results were found after corn crop plantation, that corn residue mass was about 270 and 860 kg ha-1 on soil surface and in the 0-20 cm soil layer, respectively, after harvest in October 2008, while residue mass in the 0-20 cm soil layer was only 466 kg ha-1 in T but 863 kg ha-1 in NT before planting in May 2009. So T had effectively sequestered soybean residue into soil but not corn. Results also showed that T after harvest helped to improve soil available N, P, soil microbial biomass carbon （MBC）, and nitrogen （MBN） contents and soil enzymes activities （urease, acid phosphatase, and protease） during the 2007 and 2008 seasons, but the positive effects decreased during the 2009 season. T practice had significant positive effects on available N, P, MBC, and MBN contents, protease and urease activities, however, no obvious effects on acid phosphatase activity. In this study, T practice after soybean harvest was proved to be preferable to improve soil microbial and enzyme activities during the following seasons due to an efficient sequestration of soybean residues. However, NT could be considered preferential

关键词： crop residues tillage soil biochemical properties Northeast China

宫颈液基细胞学水泡状胎块误诊宫颈恶性肿瘤1例报道

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诊断病理学杂志 2025年第1期32卷 106-107,113页

作者：周保坤刘晓丽许婷张晓芳刘洪丽张腾赵琳丽王建丽山东大学齐鲁医院妇产科济南250012 山东大学齐鲁医院病理科济南250012 山东大学齐鲁医院超声科济南250012

目的探讨水泡状胎块(又称葡萄胎)患者宫颈阴道液基涂片细胞学特点,并为临床医生诊断提供帮助。方法收集一例宫颈液基细胞学(TCT)检查误诊为恶性肿瘤的水泡状胎块患者的临床资料。结果患者否认有同房史,临床查体无明显阳性体征,B超辅助... 详细信息

目的探讨水泡状胎块(又称葡萄胎)患者宫颈阴道液基涂片细胞学特点,并为临床医生诊断提供帮助。方法收集一例宫颈液基细胞学(TCT)检查误诊为恶性肿瘤的水泡状胎块患者的临床资料。结果患者否认有同房史,临床查体无明显阳性体征,B超辅助检查也无水泡状胎块提示,且β-hCG检查结果未知,TCT发现大量分散的、核浆比增大的、核深染的大单核细胞。组织病理显示绒毛间质水肿、滋养细胞增生,免疫组化提示p57阴性,诊断为完全性水泡状胎块。结论在宫颈细胞诊断过程中,当发现多核巨细胞或滋养(和/或中间滋养)细胞时,即便没有临床病史和辅助检查,也要想到水泡状胎块的可能性,从而避免误诊。

关键词：宫颈液基细胞学水泡状胎块葡萄胎宫颈鳞状细胞癌滋养细胞

Development of the Embedded Protective Device Based on ARM

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Journal of China University of Mining and Technology 2005年第4期15卷 344-347页

作者： liu xiao-wen li Na PAN Chun-de School of Information ＆ Electrical Engineering China University of Mining ＆ Technology Xuzhou Jiangsu 221008 China

An embedded protective device for 35kV power line is worked out based on Philips’ LPC2292 ARM MCU. Several aspects such as embedded design technique adopted in the system framework, application of adaptive theory in data acquisition, Board Support Packet (BSP) developing and task dispatching related to operating system are discussed. Both hardware and software framework of the system are given. Advanced hardware platform and software development environment is applied in design of the system, with the advanced co-design technology.

关键词： microcomputer protective device ARM embedded operating system adaptive theory BSP

Synthesis of Iron Chlorophyllins and Their Catalytic Performance for Aerobic Oxidation of Cyclohexene

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Chemical Research in Chinese Universities 2013年第3期29卷 526-532页

作者： liu xiao-hong li Yong-jin YANG Wei-jun GUO Can-cheng College of Chemistry and Chemical Engineering Hunan University Changsha 410082 P. R. China

A series of iron（III） chlorophyllins was prepared from silkworm excrement crude chlorophyll extract as a raw material. Aerobic oxidation of cyclohexene by using the prepared iron（III） chlorophyllins as biomimetic catalysts was studied under atmospheric pressure in the absence of reducing agent and solvent. The results indicate that chloro- phyll iron porphyrins have better catalytic performance than the industrial-applied iron tetraphenylporphyrin and cobalt tetraphenylporphyrin, and possess a higher selectivity for 2-cyclohexen-1-one. The smaller the polarity of iron（III） chlorophyllin＇s ligand is, the easier the catalytic oxidation of cyclohexene will be. Esterification products of iron（III） chlo- rophyllins can catalyze the oxidation of cyclohexene better than non-esterified iron（III） chlorophyllins, and therefore show a higher conversion of cyclohexene and a higher selectivity for 2-cyclohexen-l-one than the non-esterified ones. Among the six synthesized iron（III） chlorophyllin catalysts, iron（III） methyl-pyropheophorbide-a is the best biomimetic catalyst for the highest conversion of cyclohexene. The influences of catalyst＇s substituent, polarity and ring structure on the catalytic performance were discussed. The catalytic performance of iron（III） chlorophyllins improves with decreasing polarity, increasing conjugated degree of porphyrin＇s ring or enhancing chlorophyllins＇ stability. Possible mechanism of cyclohexene aerobic oxidation catalyzed by iron（III） chlorophyllins was also discussed.

关键词： Chlorophyll Iron chlorophyltin Air Cyclohexene Catalytic oxidation