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Optical Properties of Neodymium Substituted Bismuth Titanate Thin Film Grown by Metal-organic Solution Deposition

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Journal of Materials Science & Technology 2010年第11期26卷 977-980页

作者： Yuehua Wang Xinyin Zhao na Zhao min Zhang Department of Physics China University of Mining and Technology Xuzhou 221116 China

Well-crystallized Bi2Nd2Ti3O12 （BNT） thin film with good surface morphology was prepared by metal-organic solution deposition （MOD）.The waveguide property was investigated by using a Metricon 2010 prism *** nonlinear optical properties of the film were measured by Z-scan technique at a wavelength of 532 nm with pulse durations of 35 ps.A large positive nonlinear refractive index,nonlinear refractive coefficient and two-photon absorption coefficient were determined to be 2.7×10-7 esu,5.29×10-7 esu and 2.41×10-7 m/W,*** origin of optical nonlinearity of BNT thin film was *** results suggested that the the BNT thin film may be a kind of new multifunctional materials.

关键词： Bi2Nd2Ti3O12 Optical property Metal-organic solution deposition

Detection,isolation,and identification of cadmium-resistant bacteria based on PCR-DGGE

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Journal of Environmental Sciences 2007年第9期19卷 1114-1119页

作者： HU Qing DOU min-na QI Hong-yan XIE Xiang-ming ZHUANG Guo-qiang YANG min Department of Environmental Biotechnology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China. Biology Science and Technology College Beijing Forestry University Beijing 100083 China

This study focused on the screening of cadmium-resistant bacterial strains from Pb-Zn tailing. We investigated the diversity of microbial community inhabiting Dong-san-cha Pb-Zn tailing in Beijing, China, by polymerase chain reaction-denaturing gradient gel electrophoresis （DGGE） of 16S rRna gene of bacterial strain, and found two dominant strains in the DGGE profile. Using special culture media, we isolated two strong cadmium-resistant bacterial strains. On the basis of morphological, physiological, and biochemical characteristics, BIOLOG, and 16S rDna sequencing, the two strains were identified as Bacillus cereus and Enterobacter cloacae. minimal inhibitory concentrations （MICs） of heavy metals for the bacteria were determined. E. cloacae showed higher MIC values for heavy metals and a larger range of antibiotic resistance than B. cereus.

关键词： Bacillus cereus Enterobacter cloacae PCR-DGGE cadmium resistance antibiotic resistance

Tempering stability of Fe–Cr–Mo–W–V hot forging die steels

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International Journal of minerals,Metallurgy and Materials 2017年第10期24卷 1145-1157页

作者： Yuan-ji Shi Xiao-chun Wu Jun-wan Li na min School of Materials Science and Engineering Shanghai University Shanghai 200072 China

The tempering stability of three Fe–Cr–Mo–W–V hot forging die steels(DM, H21, and H13) was investigated through hardness measurements and transmission electron microscopy(TEM) observations. Both dilatometer tests and TEM observations revealed that DM steel has a higher tempering stability than H21 and H13 steels because of its substantial amount of M_2C(M represents metallic element) carbide precipitations. The activation energies of the M_2C carbide precipitation processes in DM, H21, and H13 steels are 236.4, 212.0, and 228.9 kJ/mol, respectively. Furthermore, the results indicated that vanadium atoms both increase the activation energy and affect the evolution of M_2C carbides, resulting in gradual dissolution rather than over-aging during tempering.

关键词： tempering stability hot forging die steels carbide precipitation

Molecular Characterization and Functional Analysis of Krüppel-homolog 1(Kr-h1) in the Brown Planthopper, Nilaparvata lugens(Stl)

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Journal of Integrative Agriculture 2014年第9期13卷 1972-1981页

作者： JIN min-na XUE Jian YAO Yun LIN Xin-da College of Life Sciences China Jiliang University Institute of Insect Science Zhejiang University

The brown planthopper, Nilaparvata lugens（Stl）, is the most serious insect pest of rice. It has developed high resistance to traditional insecticides because of their intensive use. Juvenile hormone（JH） analogs have been used successfully to control this species and other pest insects. However, the molecular mechanism of JH signaling is not well understood. Krüppel-homolog 1（Kr-h1） is a transcription factor involved in the JH pathway. In this study, the Kr-h1 cDna was cloned and characterized from N. lugens by rapid amplification of cDna ends（RACE） and reverse transcription PCR（RT-PCR）. Its spatial and temporal expression profiles were examined by real-time quantitative PCR, and its function was also studied by Rna interference（Rnai）. The open reading frame of NlKr-h1 is 1 833 bp encoding for 611 amino acids. The protein contains eight conserved zinc-finger motifs. NlKr-h1 was expressed at all life stages, with the highest mRna level in the 4-day embryo. NlKr-h1 mRna levels rose during each nymphal molt after the 2nd instar. In the adults, the mRna level in males was significantly higher than that in females of either the macropterous or brachypterous type. The highest expression was observed in the female midgut. NlKr-h1 was activated by juvenile hormone III（JH III） in the 3rd-5th instar nymphs. Disruption of Nlkr-h1 expression by Rnai caused stunted wing development and malformations of both male and female external genitalia. Our findings suggest that Kr-h1 may be a useful target for pest insect management.

关键词： brown planthopper Krüppel-homolog 1 Rna interference juvenile hormone signaling pathway

Formation Sites and Microscopic Conformation Study on the Konjac Glucomannan Molecular Helices

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Chinese Journal of Structural Chemistry 2010年第7期29卷 1084-1090页

作者： JIAN Wen-Jie WANG Meng YAO min-na PANG Jie Department of Biological Technology Xiamen Ocean Vocational College Xiamen 361012 China College of Food Science Fujian Agriculture and Forestry University Fuzhou 350002 China

In this work, the formation sites, helical parameters and hydrogen bond positions of Konjac glucomannan molecular helices were investigated using molecular dynamic simulation method. To our interest, the KGM chain is mainly composed by local left and right helix struetttres. The formation sites of KGM chain might locate at the chain-segments containing acetyl groups, and the left helix is the favorable conformation of KGM. Temperature-dependent molecule conformation study indicates that the right helix is dominant when the temperature is lower than 343 K, above which, however, the left helix is dominating （right helix disappears）. In addition, intramolecular hydrogen bonds in the left helix can be found at the -OH groups on C（2）, C（4） and C（6） of mannose residues; comparably, the intramolecular hydrogen bonds in the right helix can be mainly observed at the -OH groups on C（4） and C（6） of the mannose residues and C（3） of the glucose residues. In conclusion, molecular dynamic simulation is an efficient method for the microscopic conformation study of glucomannan molecular helices.

关键词： Konjac glucomannan helical structure formation sites helical parameters,hydrogen bond sites

Roles of Carbohydrate Supply and Ethylene,Polyamines in Maize Kernel Set

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Journal of Integrative Plant Biology 2011年第5期53卷 388-398页

作者： Han-Yu Feng Zhi-min Wang Fan-na Kong min-Jie Zhang Shun-Li Zhou College of Agronomy & Biotechnology China Agricultural University Beijing 100193 China

Glucose appears to have an antagonistic relationship with ethylene and ethylene and polyamines appear to play antagonistic roles in the abortion of seeds and fruits. Moreover, ethylene, spermidine, and spermine share a common biosynthetic precursor. The synchronous changes of them and the relationships with kernel set are currently unclear. Here, we stimulated maize （Zea mays L.） apical kernel set and studied their changes at 4, 8, 12, and 16 d after pollination （DAP）. The status of the apical kernels changed from abortion to set, showing a pattern similar to that of the middle kernels, with slow decrease in glucose and rapid decline in ethylene production, and a sharp increase in spermidine and spermine after four DAP. Synchronous changes in ethylene and spermidine were also observed. However, the ethylene production decreased slowly in the aborted apical kernels, the glucose and polyamines concentrations were lower. Ethephon application did not block the change from abortion to set for the setting apical kernels. These data indicate that the developmental change may be accompanied by an inhibition of adequate glucose to ethylene synthesis and subsequent promotion of spermidine and spermine synthesis, and adequate carbohydrate supply may play a key role in the developmental process.

关键词： CARBOHYDRATES ETHYLENE POLYAminES CORN POLLInaTION SPERMIDINE ETHEPHON GLUCOSE

Z-Guggulsterone alleviated renal fibrosis and G_(2)/M cycle arrest through Klotho/P53 signaling

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中国药理学与毒理学杂志 2021年第10期35卷 767-768页

作者： LIU min-na LIU Tian-long Department of Nephrology the 940th Hospital of PLA Joint Logistics Support ForcesLanzhou 730050China Department of Clinical Pharmacy the 940th Hospital of PLA Joint Logistics Support ForcesLanzhou 730050China

OBJECTIVE Chronic kidney disease(CKD)has become a global public health problem with 10%-15%incidence rate,and inhibiting the renal interstitial fibrosis is considered to be a potential strategy to delay the progression of CKD.Z-Guggulsterone(Z-GS),an active compound from derived from Commiphora mukul,has been proved to be effective in various *** present study aimes to determine the protective effect and the molecular mechanism of Z-GS on renal *** Unilateral ureteral obstruction(UUO)mice and hypoxia-induced HK-2 cells were used to simulate renal fibrosis in vitro and in vivo,*** mice and cells were treated with different doses of Z-GS to observe the pharmacological *** function,including Scr,BUN,and UA,were detected by commercial kits.H&E and Masson staining were performed to observe histopathological changes of *** viability and LDH release of HK-2 cells were detected by commercial *** cycle distribution and apoptosis rate were analyzed by flow *** markers were detected by immunohistochemistry and immunofluorescence *** cycle related proteins and Klotho/p53 signaling were analyzed by Western *** The results showed that Z-GS decreased the rise of Scr,BUN,and UA and lightened renal histopathological injury,which were induced by ***,Z-GS administration alleviated renal fibrosis in mice by inhibiting the expressions ofα-SMA,TGF-βand collagenⅣ,and delayed G2/M cell cycle arrest by promoting the expressions of CDK1 and cyclinD1/B1 *** in vitro indicated that Z-GS treatment significantly increased the cell viability while decreased the LDH release in hypoxia-induced HK-2 *** addition,hypoxia induced fibrosis and G2/M cycle arrest in HK-2 cells were retarded by *** study of its possible mechanism exhibited that Z-GS treatment increased the level of Klotho and inhibited P53 ***,the effect of Z-GS on Klotho/P53 signaling was reversed

关键词： chronic kidney disease renal interstitial fibrosis Z-Guggulsterone G2/M cycle arrest Klotho/P53 signaling

Molecular Dynamics Simulations of the Interactions Between Konjac Glucomannan and Soy Protein Isolate

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Agricultural Sciences in China 2010年第10期9卷 1538-1542页

作者： WANG Meng YAO min-na JIAN Wen-lie SUN Yu-jing PANG Jie College of Food Science Fujian Agriculture and Forestry University Fuzhou 350002 P.R.China College of Biosystem Engineering and Food Science Zhejiang University Hangzhou 310029 P.R.China

The interactions between konjac glucomannan（KGM） and soy protein isolate （SPI） were studied with the method of molecular dynamics simulation. Part representative structures segments of KGM and SPI were used as mode, and the force-field was FF03. The stability and sites of KGM/SPI interactions in water were researched at 363 K with the following results： the potential energy （EPOT） of the mixed gel dropped, while that of single KGM gel increased. The surface area （SA） of KGM in the mixed system was decreased to 401.41 from 1 267.54 Az, and that of SPI to 484.94 from 1 943.28 A2. The sum potential energy of KGM and soy protein in the mixed system was decreased to -13 402.41 from -5 768.56 kcal mol^-1. The variations of two parameters showed that the stability of compound gel KGM/SPI was improved, which was consistent with the previous studies. The sites of interactions in the mixed gel were the -OH groups on C（2） in KGM mannose and glucose, and the amide linkage group on Histidine, Asparagine and Leucine in SPI. The hydrogen bond was formed directly or indirectly by the bridge of waters.

关键词： KGM SPI molecular dynamics simulation interaction

Synthesis and Crystal Structure of a New Noble Metalcontaining Supramolecular Self-assembly with Decamethylcucurbit[5]uril

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Chinese Journal of Structural Chemistry 2020年第3期39卷 535-542,379页

作者： CHEN Ru-Ru YANG Wei-Guang CAO min-na LI Hong-Fang College of Chemistry Fuzhou UniversityFuzhou 350002China State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou 350002China

A new supramolecular self-assembly [Li(H2 O)2]2[(H2 O@Me10 CB[5])][PtC l6]·7 H2 O(1, Me10 CB[5] = decamethylcucurbit[5]uril), has been successfully constructed with Me10 CB[5] and [PtCl6]^(2-) anion in the presence of lithium cation(Li+). Single-crystal X-ray diffraction study reveals that compound 1 crystallizes in monoclinic space group P21/n with a = 11.1681(18), b = 28.5425(4), c = 18.9342(3) ?, β = 99.0143(15)°, V = 5961.02(16) ?~3, Z = 4, F(000) = 3224, μ = 2.714 mm^(-1), R = 0.0470 and wR = 0.1076(I > 2σ(I)). In the supramolecular self-assembly, two of the portal carbonyl oxygen atoms of Me10 CB[5] are coordinated to Li+ cation, yielding a "half-open" molecular capsule. Then adjacent molecular capsules are connected with each other through hydrogen-bonding to form a one-dimensional(1 D) supramolecular chain structure. The [PtCl6]^(2-) anions are fixed on one side of the 1 D supramolecular chain through supramolecular interactions. The thermal stability, electronic valence and morphology of compound 1 are also investigated.

关键词： decamethylcucurbituril noble metal supramolecular self-assembly crystal structure