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Integrated Expression of the Oenococcus oeni mleA Gene in Saccharomyces cerevisiae

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Agricultural Sciences in China 2009年第7期8卷 821-827页

作者： liu yan-lin li Hua College of Enology Northwest A ＆F University/Shaanxi Engineering Research Center for Viti-Viniculture Yangling 712100 P.R. China

Malolactic enzyme is the function enzyme which catalyses the reaction for L-malate converting to L-lactic during malolactic fermentation （MLF）. In this paper, researches concerning the malolactic enzyme gene mleA cloned from a patent strain Oenococcus oeni SD-2a screened in Chinese wine and integrated expressing in Saccharomyces cerevisiae were performed in order to carry out both alcoholic fermentation （AF） and malolactic fermentation （MLF） during winemaking, with a view to achieving a better control of MLF in enology. To construct the expression plasmid named pYILmleA, cloned mleA gene, PGK1 promoter, and ADH1 terminator were ligated and inserted into integrating vector YIp5. Yeast transformants were screened on SD/-Ura and identified by auxotrophic test, mating type test, and colony PCR. Target protein was detected by SDS-PAGE and the targeted gene integrated to the chromosome was detected by dot bloting hybridization. After the transformant was cultured in SD/-Ura adding glucose （10%） and L-malate （5 648 mg L-1） for 4 d, the culture supernatant was collected and L-malate and L-lactic acid contents were detected by HPLC. 1 278-1 312 mg L-1 L-lactic acids were detected, while the comparative drop rates of L-malate were 20.18-20.85%. L-malate and L-lactic contents of the transformants showed extra significant difference and significant difference with the control ones by t-test respectively. The result indicated that the functional expression was achieved in recombinants S. cerevisiae.

关键词： Oenococcus oeni malolactic enzyme gene integrated recombinant expression Saccharomyces cerevisiae

Qualitative Description of Swashing Motion States on Mild Beach Slope

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China Ocean Engineering 2019年第4期33卷 412-423页

作者： YIN Jing ZOU Zhi-li FANG Ke-zhao liu yan-li State Key Laboratory of Coastal and Offshore Engineering Dalian University of Technology Dalian 116024 China Key Laboratory of Sea-Area Management Technology National Marine Environmental Monitoring Center Dalian 116024 China

The swashing motion on mild beach slope is dominated by the motion of low frequency waves (LFWs). Companying such a motion, there are two types of swashing motion states, occurrence or no occurrence of LFW’s collision. The present study distinguishes the two states qualitatively by relating it to the number of generated LFWs for the case of two incident wave groups. A simplified swashing index is established theoretically for this purpose. A series of related experiments were performed to observe the generated out-going LFWs on different mild slope from 1:20 to 1:160 and to determine the critical value of the swashing index. Numerical simulations based on higher order Boussinesq equations are also performed to help the recognition of the LFWs generated in the experiment.

关键词： swashing surf beat braking wave low frequency wave wave groups

Molecular Cloning and Bacterial Expression of Germacrene A Synthase cDNA from Crepidiastrum sonchifolium

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Chemical Research in Chinese Universities 2006年第5期22卷 606-611页

作者： REN Jie liu yan-qiu yanG li NI Rui YOU Song School of Pharmaceutical Engineering Shenyang Pharmaceutical UniversityShenyang 110016 P. R. China

Germacrene A synthase（GAS） catalyzes the biosynthesis of germacrene A, which is a key precursor for sesquiterpone lactones. Cloning of a novel full-length cDNA encoding GAS from the medicinal plant Crepidiastrum sonchifolium（dosignated CsGAS） is reported in this study. The cDNA is 1837 bp long and contains a 1680-bp open reading frame encoding a 559 amino-acid protein. The functional expression of the cDNA in Escherichia coli, as an N-terminal thioredoxin fusion protein, with the pET32a vector yielding a recombinant enzyme. Sequence analysis was used to compare this enzyme with the mechanistically related epi-aristolochene synthase from tobacco, and the effect of possible involvement of a number of amino acids in sesquiterpone synthase on product specificity was also discussed.

关键词： Germacrene A synthase Crepidiastrum sonchifolium Sesquiterpene synthase Expression Fusion protein

Photon-Induced Production of Mirror Quarks from LHT Model at LHC

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Communications in Theoretical Physics 2009年第12期52卷 1041-1048页

作者： YUE Chong-Xing liu Jin-yan DING li liu Wei MA Wei Department of Physics Liaoning Normal University Dalian 116029 China

The photon-induced processes at the LHC provide clean experimental conditions due to absence of theproton remnants,which might produce complementary and interesting results for tests of the standard model and forsearching of new *** the context of the littlest Higgs model with T-parity,we consider the photon-inducedproduction of the mirror quarks at the *** cross sections for various production channels are calculated and asimply phenomenological analysis is performed by assuming leptonic decays.

关键词： the mirror fermions the LHT model the LHC

Volume change behavior of unsaturated soils under non-isothermal conditions

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Chinese Science Bulletin 2011年第23期56卷 2495-2504页

作者： CAI GuoQing ZHAO ChengGang liu yan li Jian Department of Geotechnical and Geoenvironmental Engineering School of Civil Engineering and Architecture Beijing Jiaotong UniversityBeijing 100044 China

With the development of modern geotechnical engineering practices such as the construction of high level radioactive waste repositories, exploitation and utilization of geothermal resources, energy-saving buildings and underground storage of CO 2 , research into the influence of temperature on the basic mechanical properties of unsaturated soils has become an important issue internationally. By using the work expression and considering the influence of temperature on the basic properties of unsaturated soils, the average soil skeleton stress, modified suction and temperature were selected as state variables of generalized forces in thermodynamics and the soil skeleton strain, saturation and entropy were chosen as state variables of generalized flows conjugate to the variables of generalized forces. Based on the nonlinear multi-field coupled model and by using existing experimental results, an elastic-plastic constitutive model of unsaturated soils under non-isothermal conditions was developed to analyze the influence of temperature on the deformation properties of unsaturated soils. The model was used to predict and analyze the influence of suction and temperature on the deformation properties of unsaturated soils under isotropic conditions, and was successfully verified using experimental results.

关键词：非饱和土非等温条件高放射性废物处置库弹塑性本构模型行为体积状态变量耦合模型

Synthesis of Conjugated Aryleneethynylenesiloles Dendron

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Chinese Journal of Chemistry 2012年第12期30卷 2861-2868页

作者： liu Jie yan Chenxu li Shanshan Wang Chengyun Shen Yongjia Key Laboratory for Advanced Materials and Institute of Fine Chemicals East China University of Science and Technology Shanghai 200237 China

Three routes were designed to synthesize a n-conjugated aryleneethynylenesiloles dendron. With the desilylation of the disilole mono（silylethynyl） derivative in the presence of potassium carbonate （K2CO3）, the silole-containing oligomer has been successfully synthesized without impact on the Si-（CH3）2 group. The disilole mono- （silylethynyl） derivative was prepared by means of the Sonogashira heterocoupling reaction between the diacetylene compound and asymmetrical silole, catalyzed by the dichloro bis（triphenylphosphine）palladium, in a divergent synthesis. Due to their steric effect and triethynylbenzene self-coupling Glaser reaction, the endeavour to prepare the dendron by controlling the molar ratio of asymmetrical silole and 1,3,5-triethynylbenzene was failed. The another attempt to prepare the dendron by different desilylation condition of triisopropylsilyl group and trimethylsilyl group was also failed, the desilylation of Si-（CH3）2 group in silacyclopentadiene unit was also easily accomplished in the presence of tetrabutylammonium fluoride（Bu4NF）, whereas no reaction occurred when K2CO3 was used instead of Bu4NF.

关键词： heterocycles dendrimers silole sonogashira reaction desilylation

Gridded inventories of historical usage for selected organochlorine pesticides in Heilongjiang River Basin, China

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Journal of Environmental Sciences 2006年第4期18卷 822-826页

作者： liu li-yan JIANG An-xi REN Nan-qi JIANG Gui-bin li Yi-fan School of Municipal and Environmental Engineering ＇Harbin Institute of Technology Harhin 150090 China Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Atmospheric Environment Service Environment Canada Downsview Ontario Canada

The use of technical HCH （1, 2, 3, 4, 5, 6-hexachlorocyclohexane）, DDT （dichlorodiphenyltrichloroethane） and lindane in Heilongjiang River Basin （HRB） of China was studied. Between 1952 and 1984 the total usage in the HRB was 108900 t for technical HCH, and 4900 t for DDT, respectively, and the use of DDT due to dicofol application in the HRB was 220 t from 1984 to 2003. The usage of lindane in HRB was 109 t from 1991 to 2000. The results show that the highest technical HCH use （41800 t） in HRB was on maize, accounting for 38.3% of the total usage on all crops, followed by the use on wheat （28000 t, 25.7%） and on soybean （26600 t, 24.4%）. The highest DDT use （2300 t） was on soybean, accounting for 46.8% of the total usage on all crops, followed by the use on maize （1500 t, 31.3%） and on sorghum （600 t, 13.2%）. The major use of lindane was mainly on wheat. Gridded usage inventories of these three OCPs （organochlorine pesticides）, in HRB with a 1/6° latitude by 1/4° longitude resolution have been created by using different gridded cropland as surrogates. Some soil samples have also been collected in HRB. Data of usage and soil concentrations of 5： HCH in HRB match quite well to those in Shanghai region, and much higher soil concentration of 5： DDT in Shanghai region could be due to much heavier dicofol use in this region.

关键词： persistent organic pollutants (POPs) organochlorine pesticides (OCPs) DDT HCH lindane inventories Heilongjiang River Basin

Dynamic Relationship Between Biologically Active Soil Organic Carbon and Aggregate Stability in Long-Term Organically Fertilized Soils

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Pedosphere 2012年第5期22卷 616-622页

作者： li Cheng-liang XU Jiang-Bing HE Yuan-Qiu liu yan-li FAN Jian-Bo College of Resources and Environment Shandong Agricultural UniversityTai'an 271018(China) Institute of Soil Science Chinese Academy of SciencesNanjing 210008(China) National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources Tai'an 271018(China)

Biologically active soil organic carbon （BASOC） is an important fraction of soil organic carbon （SOC）, but our understanding of the correlation between BASOC and soil aggregate stability is limited. At an ecological experimental station （28° 04＇-28° 37＇ N, 116° 41＇-117° 09＇ E） in Yujiang County, Jiangxi Province, China, we analyzed the dynamic relationship between soil aggregate stability and BASOC content over time in the red soil （Udic Ferrosols） fertilized with a nitrogen-phosphorus-potassium chemical fertilizer （NPK） without manure or with NPK plus livestock manure or green manure. The dynamics of BASOC was evaluated using CO2 efflux, and soil aggregates were separated according to size using a wet-sieving technique. The soils fertilized with NPK plus livestock manure had a significantly higher content of BASOC and an improved aggregate stability compared to the soils fertilized with NPK plus green manure or NPK alone. The BASOC contents in all fertilized soils decreased over time. The contents of large aggregates （800-2 000 μm） dramatically decreased over the first 7 d of incubation, but the contents of small aggregates （〈 800 μm） either remained the same or increased, depending on the incubation time and specific aggregate sizes. The aggregate stability did not differ significantly at the beginning and end of incubation, but the lowest stability in all fertilized soils occurred in the middle of the incubation, which implied that the soils had a strong resilience for aggregate stability. The change in BASOC content was only correlated with aggregate stability during the first 27 d of incubation.

关键词： aggregate size CO2 release manure mean weight diameter organic fertilization

Simulation of Voltage SET Operation in Phase-Change Random Access Memories with Heater Addition and Ring-Type Contactor for Low-Power Consumption by Finite Element Modeling

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Chinese Physics Letters 2010年第6期27卷 250-253页

作者： GONG Yue-Feng SONG Zhi-Tang liNG Yun liu yan li Yi-Jin State Key Laboratory of Functional Materials for Informatics Laboratory of Nanotechnology Shanghai Institute of Micro-system and Information Technology Chinese Academy of Sciences Shanghai 200050

A three-dimensional finite element model for phase change random access memory is established to simulate electric, thermal and phase state distribution during （SET） operation. The model is applied to simulate the SET behaviors of the heater addition structure （HS） and the ring-type contact in the bottom electrode （RIB） structure. The simulation results indicate that the small bottom electrode contactor （BEC） is beneficial for heat efficiency and reliability in the HS cell, and the bottom electrode contactor with size Fx=80 nm is a good choice for the RIB cell. Also shown is that the appropriate SET pulse time is lOOns for the low power consumption and fast operation.

关键词： SIMULATION methods & models PHASE transformations (Physics) RANDOM access memory ELECTRODES REliABIliTY (Engineering) ENERGY consumption