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Channel-aware and queue-aware joint-layer resource optimization for cognitive radio networks

2011 World Congress on engineering and technology(CET 2011)

作者： shaofeng li 1 1.jiangsu engineering and technology research center for microbiology resource jiangsu Key Laboratory for Biodiversity and Biotechnology College of life Science Nanjing Normal University Nanjing China Yuru Chen 1 2 2.Department of Biotechnology Taizhou College Nanjing Normal University Taizhou China Kewei Dai 3 3.School of Geography Science Nanjing Normal University Nanjing China Shijie Yang 4 4.School of life Science and Environment College of Yichun Yichun China

Methods for separation of chlorogenic acid in tobacco materials *** liquid chromatography-mass spectrometry （LC-MS） method for identification and analysis of chlorogenic acids from tobacco material has been *** acid （CQA） were isolated by polyamide column chromatography and further purified by silica gel column *** revealed that polyamide is suitable for separation chlorogenic acid from tobacco *** eluant was collected for two-step column chromatography of *** content of chlorogenic acid of the purified product was 40.3%.After further purification by silica gel column chromatography,the content of total chlorogenic acids was 92.2%.The LC-MS results showed that total chlorogenic acids were made up of four components: 5-CQA,3-CQA,4-CQA and *** content of 5-CQA was the most （78.2%） and other three chlorogenic acid derivatives were 1.9%,10.1% and 2.0% respectively.

关键词： tobacco chlorogenic acid polyamide separation liquid chromatography-mass spectrometry (LC-MS)

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Science China(Information Sciences) 2010年第12期53卷 2576-2583页

作者： GUO KunQi 1,2,SUN liXin 1,li Yong 2 & JIA ShiLou 3 1 School of Computer Science and Telecommunication engineering,jiangsu University,Zhenjiang 212013,China 2 research center for Wireless Communication,Shanghai Institute of Microsystem and Information technology,Chinese Academy of Sciences,Shanghai 200050,China 3 Communication research center,Harbin Institute of technology,Harbin 150001,China 1. School of Computer Science and Telecommunication engineering Jiangsu University Zhenjiang 212013 China2. Research Center for Wireless Communication Shanghai Institute of Microsystem and Information Technology Chinese Academy of Sciences Shanghai 200050 China3. Communication Research Center Harbin Institute of Technology Harbin 150001 China

An optimization model is derived to maximize the utilization efficiency of the idle channels of primary users(PU) in cognitive radio *** the optimization model,Lyapunov optimization method is used to allocate the idle channels of PU to secondary user(SU) most *** time distribution of the idle channels of PU is predicted by a low-pass time *** algorithm is proposed to implement the optimization *** algorithm is efficient because of using a greedy selection *** efficiency of the algorithm is demonstrated by mathematic analyses and simulation results.

关键词： cognitive radio networks Lyapunov optimization resource utilization primary user secondary user

Genetic analysis of segregation distortion of mating-type factors in Lentinula edodes

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Progress in Natural Science:Materials International 2005年第8期15卷 684-688页

作者： CHENG Shuiming 1,2, liN Fanxue1, XU Xuefeng1, li Anzheng1 and liN Fangcan1*(1. State Key Laboratory of Agricultural microbiology and Institute of Applied Mycology, Huazhong Agricultural University, Wuhan 430070, China 2. National engineering research center For Wheat, Henan Agricultural University, Zhengzhou 450002, China) State Key Laboratory of Agricultural microbiology and Institute of Applied Mycology Huazhong Agricultural University Wuhan 430070 China. National engineering research center For Wheat Henan Agricultural University Zhengzhou 450002 China

Analyses of the mating-type ratio of protoplast monokaryons to spores in 28 strains of Lentinula edodes were performed through statistical methods. The results showed that the segregation distortion phenomenon commonly exists in both types of Lentinula edodes, 17 out of the 28 samples did not display the expected 1∶1 ratio of protoplast monokaryons; and among them 8 fruiting strains distorted 1∶1∶1∶1 segregation of spores. The degree of distortion in all tested wild strains was significantly lower than that of cultured strains. In fruiting test of positive-negative parent, predominant spores were those with the mating type identical to dikaryotic parent, indicating that the predominance of nuclei mainly depends on the mating type of dikaryotic parent. Data from di-mon mating test verified that monokaryons with acceptor nuclear type are present exclusively in a large amount after dedikaryotization, suggesting that the specificities among B factors and some other unknown factors in cytoplasm are probably responsible for the phenomenon of skewed segregation.

关键词： Lentinula edodes mating-type factors segregation distortion cytoplasm.

Adsorption of surfactants onto acrylic ester resins with different pore size distribution

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Science China Chemistry 2006年第5期49卷 445-453页

作者： YANG Weiben1,2,3,li Aimin1,3,CAI Jianguo1,3,MENG Guanhua1,3 & ZHANG Quanxing1,3 1. State Key Laboratory of Pollution Control and resource Reuse,School of the Environment,Nanjing University,Nanjing 210093,China 2. Nanjing College of Chemical technology,Nanjing 210048,China 3. jiangsu engineering & technology research center for Organic Toxicant Control and resource Reuse,Nanjing 210038,China 1. State Key Laboratory of Pollution Control and resource Reuse School of the Environment Nanjing University Nanjing 210093 China 2. Nanjing College of Chemical technology Nanjing 210048 China 3. jiangsu engineering & technology research center for Organic Toxicant Control and resource Reuse Nanjing 210038 China

In this study, a series of acrylic ester resins with different pore size distribution were prepared successfully by varying the type and the amount of pore-forming agents. In order to inves-tigate the adsorption behavior and mechanism of surfactants on acrylic ester resins, three kinds of surfactants were utilized as adsorbates that were sodium 6-dodecyl benzenesulfonate (6-NaDBS), sodium 1-dodecyl benzene sulfonate (1-NaDBS) and sodium 1-dodecyl sulfonate, respectively. It was observed that the surface area was available in a particular pore size and an appropriate pore size of resins appeared to be more important for the adsorption of surfactants. As compared to commercial acrylic ester resins XAD-7 and HP2MG, 50# and 38# resins exhibited more excellent adsorption properties toward 1-NaDBS and 6-NaDBS. The experimental equilibrium data were fitted to the Langmuir, and double-Langmuir models. Two models provided very good fittings for all resins over the temperature range studied. The investigation indicated that electrostatic attraction and hydrogen bond between resins and surfactants were the main forces and had an obvious effect on adsorption proc-ess.

关键词： acrylic ester resin, surfactant, adsorption, pore size distribution, isotherm.

One-dimensional nonlinear consolidation of soft clay with the non-Darcian flow

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Journal of Zhejiang University-Science A(Applied Physics & engineering) 2013年第6期14卷 435-446页

作者： Chuan-xun li Kang-he XIE Faculty of Civil engineering and Mechanics Jiangsu University research center of Coastal and Urban Geotechnical engineering Zhejiang University

Based on the non-Darcian flow law described by exponent m and threshold gradient i 1 under a low hydraulic gradient and the classical nonlinear relationships e-lgσ′ and e-lgk v (Mesri and Rokhsar, 1974), the governing equation of 1D nonlinear consolidation was modified by considering both uniform distribution of self-weight stress and linear increment of self-weight stress. The numerical solutions for the governing equation were derived by the finite difference method (FDM). Moreover, the solutions were verified by comparing the numerical results with those by analytical method under a specific case. Finally, consolidation behavior under different parameters was investigated, and the results show that the rate of 1D nonlinear consolidation will slow down when the non-Darcian flow law is considered. The consolidation rate with linear increment of self-weight stress is faster than that with uniform distribution one. Compared to Darcy's flow law, the influence of parameters describing non-linearity of soft soil on consolidation behavior with non-Darcian flow has no significant change.

关键词： Non-Darcian flow Nonlinear consolidation Time-dependent loading Uniform distribution of self-weight stress linear increment of self-weight stress

A preliminary study on vegetation-erosion dynamics and its applications

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Science China Earth Sciences 2005年第5期48卷 689-700页

作者： WANG Zhaoyin 1,2 , WANG Guangqian 1 , li Changzhi 1 & WANG Feixin 1 1. Department of Hydraulic engineering, Tsinghua University, Beijing 100084, China 2. International research and Training center on Erosion and Sedimentation, Beijing 100084, China 1. Department of Hydraulic engineering Tsinghua University 100084 Beijing China 2. International research and Training center on Erosion and Sedimentation 100084 Beijing China

Vegetation-erosion dynamics is a new interdisciplinary science, studying the laws of evolution of watershed vegetation under the action of various ecological stresses. Introducing a qualitative expression of ecological stresses in this paper, the present authors establish the cou- pled differential equations for the vegetation-erosion process and derive a theoretical solution. The model is applied to the Anjiagou watershed on the Loess Pateau and the Xiaojiang water- shed and its sub-watersheds on the Yunnan Plateau. The calculated results agree well with the vegetation development processes. Abstracted from the differential equations the so-called vegetation-erosion chart is worked out, with which we can predict the development trend of vegetation under no human stresses. It is demonstrated that the erosion control is important for vegetation development and reforestation must be a long-term strategy. On the Yunnan Plateau with relatively high precipitation and temperature, vegetation can be greatly improved if erosion is controlled. On the dry and cold Loess Pateau suffering from high rate of soil erosion, however, vegetation can effectively control erosion but erosion reduction exhibits low effectiveness on vegetation development. Vegetation in the area is not stable and management is always needed to maintain the vegetation.

关键词： vegetation-erosion dynamics, human activities, coupled differential equations, erosion control, vigor ofvegetation.

Microwave Disinfection in a Ventilation and Air-Conditioning System

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湖南大学学报（自然科学版） 2009年第S1期36卷 55-59页

作者： LU Zhen1,2,ZHANG Ji-li1,MA liang-dong1,HE Juan3(1.School of Civil & Hydraulic engineering,Dalian University of technology,Dalian,liaoning 116023,China 2.Municipal and Environmental engineering research center,Shenyang Jianzhu University,Shenyang,liaoning 110168,China 3.School of Municipal & Environmental engineering,Harbin Institute of technology,Harbin,Heilongjiang 150090,China) School of Civil and Hydraulic engineering Dalian University of Technology Dalian 116023 China Municipal and Environmental engineering research center Shenyang Jianzhu University Shenyang 110168 China School of Municipal and Environmental engineering Harbin Institute of Technology Harbin 150090 China

Because of its broad spectrum and high efficiency,the microwave disinfection was used to control the airborne microbial contaminates in VAC *** microwave disinfection devices were developed combined with air filter,the design and calculation method was presented,and the disinfection effects on White staphylococcus,Staphylococcus aureus,Bacillus Subtilis,Escherichi coli were *** results show that the major influence factors on disinfection effect are microwave power,water-content of filter material,disinfecting *** 15 min,the kill ratio is >90%,and the log value is >*** microwave field is uniform and the kill effect of bacteria on each surface of filter is the same,without statistically significant difference.

关键词： VAC system microwave disinfection airborne microbe microwave power kill ratio

Biosynthetic pathway of prescription cucurbitacin IIa and high-level production of key triterpenoid intermediates in engineered yeast and tobacco

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Plant Communications 2024年第6期5卷 154-172页

作者： Geng Chen Zhaokuan Guo Yanyu Shu Yan Zhao Lei Qiu shaofeng Duan Yuan lin Simei He Xiaobo li Xiaolin Feng Guisheng Xiang Bo Nian Yina Wang Zhiyuan li Chongkang Yang Yang Shi Yingchun Lu Guanze liu Shengchao Yang Guanghui Zhang Bing Hao State Key Laboratory of Conservation and Utilization of Bio-resources in Yunnan The Key Laboratory of Medicinal Plant Biology of Yunnan ProvinceNational&Local Joint Engineering Research Center on Germplasms Innovation&Utilization of Chinese Medicinal Materials in Southwest ChinaYunnan Agricultural UniversityKunming 650201China Yunnan Characteristic Plant Extraction Laboratory KunmingYunnan 650106China

Cucurbitacin IIa is a triterpenoid isolated exclusively from Hemsleya plants and a non-steroidal anti-inflammatory drug that functions as the main ingredient of prescription Hemslecin capsules and tablets in *** biology provides new strategies for production of such valuable cucurbitacins at a large scale;however,the biosynthetic pathway of cucurbitacin IIa has been unknown,and the heterologous production of cucurbitacins in galactose medium has been expensive and low *** this study,we characterized the functions of genes encoding two squalene epoxidases(HcSE1-2),six oxidosqualene cyclases(HcOSC1-6),two CYP450s(HcCYP87D20 and HcCYP81Q59),and an acyltransferase(HcAT1)in cucurbitacin IIa biosynthesis by heterologous expression in Saccharomyces cerevisiae and Nicotiana *** achieved high-level production of the key cucurbitacin precursor 11-carbonyl-20b-hydroxy-Cuol from glucose in yeast via modular engineering of the mevalonate pathway and optimization of P450 expression *** resulting yields of 46.41 mg/l 11-carbonyl-20b-hydroxy-Cuol and 126.47 mg/l total cucurbitacin triterpenoids in shake flasks are the highest yields yet reported from engineered ***,production of 11-carbonyl-20b-hydroxy-Cuol by transient gene expression in tobacco resulted in yields of 1.28 mg/g dry weight in *** work reveals the key genes involved in biosynthesis of prescription cucurbitacin IIa and demonstrates that engineered yeast cultivated with glucose can produce high yields of key triterpenoid *** describe a low-cost and highly efficient platform for rapid screening of candidate genes and high-yield production of pharmacological triterpenoids.

关键词： cucurbitacin IIa oxidosqualene cyclase OSC 11-carbonyl-20b-hydroxy-Cuol Saccharomyces cerevisiae Nicotiana benthamiana Hemsleya chinensis

Influence of Solution Treatment on Impact Toughness and Microstructure of Cobalt-free Maraging Steel

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稀有金属材料与工程 2011年第S3期40卷 114-117页

作者： Yu Jianmin1, li Baocheng1, Zhang Baohong2, Yang Weiyu2 1North University of China, Taiyuan 030051, China 2engineering research center of Magnesium-base Material Processing technology, Ministry of Education, Taiyuan 030051, China N Univ China Coll Mat Sci & Engn Taiyuan 030051 Peoples R China Minist Educ Engn Res Ctr Magnesium Base Mat Proc Technol Taiyuan 030051 Peoples R China

The influence of different solution temperature on microstructure and impact toughness of cobalt-free maraging steel 00Ni14Cr3Mo3Ti was investigated by SEM and X-Ray *** experimental results showed that with the solution temperature variation, the martensite morphology has not changed, is still lath *** Laves phase hindered the dislocation movement after 750 ℃ solution heat treatment, which result in a very low impact absorbed energy, the impact fracture has no obvious plastic deformation, with bad *** the solution temperature increased, the undissolved phase gradually dissolved, the impact absorbed energy increased *** the Laves phase dissolved when reach to 900 ℃, the impact absorbed energy reaches the maximum, is 61 *** morphology change from brittle fracture into toughness transgranular fracture with deep dimple. When solution temperature is above 900 ℃, with the solution temperature further increase, austenite grain size increases *** grain diameter of austenite is about 70 μm after 1050 ℃ solution treatment, the density of precipitates on the grain boundary of maraging steel is increase substantially, deformation compatibility deteriorate, which result in the impact absorbed energy decreased *** type becomes transgranular and quasi-cleavage mixed fracture with the characteristics of the river patterns from ductile transgranular fracture.

关键词： cobalt-free maraging steel solution treatment impact toughness separation

Fabrication and Performances of 1-3-2 Piezoelectric Ceramic/Polymer Composite

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稀有金属材料与工程 2006年第S3期 511-513页

作者： likun Wang~1 Guang li~2 Hongliang Du~1 Lei Qin~1 Shuxiang li~1 (1.Sensor technology research center,Beijing Information technology Institute,Beijing 100101,China) (2.National Ocean technology center,Tianjin 300111,China)

A novel 1-3-2 piezoelectric composite has been developed,which consists of piezoelectric ceramic plate and 1-3 piezoelectric *** composite was fabricated by dicing PZT ceramic along mutual perpendicular two directions and then filling epoxy into *** piezoelectric and electromechanical properties of the novel composite were determined. The results show a coefficient d_ （33） of 405pC/N,a vibration displacement of 113.5pm,an acoustic impendence of 13.3 Mraly, a bandwidth of 12kHz and a thickness electromechanical coupling coefficient of 0.56.

关键词： 1-3-2 piezoelectric composite fabrication performances