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Rapid and efficient synthesis of new chiral aromatic amide molecular tweezers under solvent-free conditions using microwave

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Chinese Chemical Letters 2009年第4期20卷 397-400页

作者： Xiao Xiang Zhao zhi Gang Zhao Xing Li Liu xiu Ming Wu College of Chemistry and Environmental Protection Engineering Southwest University for Nationalities Chengdu 610041 China

An efficient and simple method for the synthesis of new chiral aromatic amide molecular tweezers by irradiation with microwave under solvent-free conditions has been developed. Its main advantages are short reaction t... 详细信息

关键词： Molecular tweezer Aromatic amide Microwave irradiation Molecular recognition

Improved One-pot Synthesis of 4,6-Dihydroxyisophthalic Acid and 2,3-Dihydroxyterephthalic Acid

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Chinese Chemical Letters 2005年第8期16卷 1039-1042页

作者： Guang Dong LEI Li Xin LI zhi Yun LU Ming gui XIE College of Chemistry Sichuan Universtiy Chengdu 610064 Department of Chemistry and Life Science Neijiang Normal College Neijiang 641112

An improved method for the large-scale preparation of 4,6-dihydroxyisophthalic acid and 2,3-dihydroxyterephthalic acid has been *** to the previous procedures,this new process-requires much lower CO2 pressure of 0.3 Mpa and shorter reaction *** providing a convenient access for large-scale *** yield is high （93% and 65%,respectively）, and the oxidation of phenol is nearly inhibited,neither decolorization nor further chromatographic purification is required.

关键词： One-pot large-scale 4,6-dihydroxyisophthalic acid 2,3-dihydroxyterephthalic acid.

Multi-slots Wideband Cooperative Spectrum Sensing Based on Weighed Data Fusion in Cognitive Radio

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Journal of Harbin Institute of Technology(New Series) 2013年第1期20卷 1-7页

作者： Xin Liu xiu-Hua Li Rong-Fei Fan Xue-zhi Tan Communication Research Centre Harbin Institute of Technology School of Electrical and Electronic Engineering Nanyang Technological University Dept. of Electrical and Computer Engineering University of Alberta

In order to avoid the interference to the primary user(PU), in this paper Cognitive Radio (CR) periodically senses the presence of PU, and during one period, CR can sense all the sub-channels based on weighed data fusion and then use all the idle channels decided by the coordinator. The local sensing time of CR is divided into multi-slots in which CR can sense any sub-channel. Through reasonably allocating the sensing slots and users by mathematic optimization, the proposed algorithm can improve the total throughput of CR. The optimization problem of the proposed scheme which seeks to maximize the throughput subject to the constraint of the detected performance of each sub-channel is proposed in order to choose the optimum local sense time and the number of the cooperative CRs. The simulation results indicate that the proposed scheme can obtain higher throughput than the conventional single-channel sense, and there are the optimum local sense time and the number of cooperative CRs to make the throughput reach maximum.

关键词： cognitive radio energy detection cooperative detection weighed data fusion thoughput

Characteristics of force chains in frictional interface during abrasive flow machining based on discrete element method

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Advances in Manufacturing 2018年第4期6卷 355-375页

作者： Tian-Xun xiu Wei Wang Kun Liu zhi-Yong Wang Dao-Zhu Wei School of Mechanical Engineering. Hefei University of Technology Hefei 230009 People's Republic of China Changzhou Borui Power Automation Equipment Co. Ltd Changzhou 213025 Jiangsu People's Republic of China

Abrading is a very important sub-technology of the surface treatment tech no logy with vast applications in the industry. This study aims at analyzing the inherent laws of friction systems during abrading. In particle flow code modeling, the abrading process can be simplified to the movement of particles in a parallel-plate shear friction system. In this study, the PFC2D software is used to construct the particle flow friction system with the set of parallel plates and the model parameters according to the abrading processing equipment and processing materials, control the simulation of a single variable, and compare the output data to estimate the impact of change of parameters on the force chain. The simulation results show that the shear dilatancy can be divided into three stages: plastic strain, macroscopic failure, and granular recombination stages. The distribution and load rates of the weak force chains depend on the load, velocity, friction coefficient between granules, granular diameter, and number of granular layers. The number of granular layers and the load increase cause the direction of the force chain to be oriented with the vertical direction, and the force chains move toward the horizontal direction as the velocity increases. The increase in load does not cause the shear dilatancy stage to occur;the velocity, friction coefficient between granules, and granular diameter increase cause the shear dilatancy to occur gradually.

关键词： Abrasion Force Machining

Synthesis and Characterization of Phosphated Konjac Glucomannan Hydrogels

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Chinese Chemical Letters 2005年第12期16卷 1652-1654页

作者： Li gui CHEN zhi Lan LIU Ying Jun CHEN Ren Xi ZHUO Key Laboratory of Biomedical Polymers of Ministry of Education Department of Chemistry Wuhan University Wuhan 430072 Department of Material Science and Engineering Shanxi University of Technology Hanzhong 723003

Konjac glucomannan （KGM） was crosslinked with sodium tripolyphosphate （STPP） to synthesize hydrogels. The crosslinking reaction was confirmed by FT-IR. The results of degradation test show that the hydrogels retai... 详细信息

关键词： Konjac glucomannan sodium tripolyphosphate hydrogels

A New Hapten for Immunoassay of Aldicarb

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Chinese Chemical Letters 2006年第8期17卷 1021-1024页

作者： Yan Feng ZHANG zhi Xian GAO Qing Min ZHANG Shu gui DAI College of Environmental Science and Engineering Nankai University Tianjin 300071 Institute of Hygiene and Environmental Medicine Tianjin 300050

A new hapten, aldicarb oxime succinic ester （AOSE）, was synthesized for immunoassay of aldicarb. It was conjugated to proteins by active ester method. Polyclonal antibody was raised against AOSE-BSA （bovine serum albumin） conjugate. Enzyme-linked immunosorbent assays （ELISAs） showed that this antiserum had high affinity to aldicarb and can be used for sensitive and selective immunoassay of aldicarb.

关键词： Aldicarb immunoassay hapten analysis.

Effects of Soil Depth and Season Variation on Community Structure of Arbuscular Mycorrhizal Fungi in Greenhouse Soils Planted with Watermelon

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Pedosphere 2013年第3期23卷 350-358页

作者： LIU Run-Jin LI Yan DIAO zhi-Kai LI Min LIN Xian-gui Institute of Mycorrhizal Biotechnology Qingdao Agricultural University State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of Sciences

The characteristics of arbuscular mycorrhizal fungal (AMF) community structure in various soil depths and growing seasons of watermelon (Citrullus vulgaris) grown in commercial greenhouses in Daxing of Beijing and Weifang and Laiyang of Shandong, China were investigated using both morphological identification and denaturing gradient gel electrophoresis. The sampled soils had been used for continuous greenhouse production of watermelon for 0, 5, 10, 15, or 20 years. Glomus claroideum was the dominant species in the greenhouse soils planted for 5, 10, and 15 years in Laiyang, while Glomus mosseae and Glomus etunicatum were dominant in the nearby open farmland soil. Sorenson's similarity index of AMF community composition ranged from 0.67 to 0.84 in the soils planted for 5 years, and from 0.29 to 0.33 for 20 years among the three locations. Spore abundance, species richness, and the Shannon index were highest near the soil surface (0-10 cm) and decreased with soil depth, and higher in June and October than in August and December. Canonical correspondence analysis showed that available P and the number of years that soil had been used for greenhouse production were the main factors contributing to the variance of AMF community composition. It was concluded that the community structure of AMF was mainly influenced by soil available P and planting time of watermelon as well as by soil depth and seasonal variation in the commercial greenhouse.

关键词： canonical correspondence analysis Shannon index Sorenson's similarity index species richness spore abundance

Malignant atrophic papulosis:Two case reports

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World Journal of Clinical Cases 2022年第35期10卷 12971-12979页

作者： zhi-gui Li Jia-Ming Zhou Li Li Xiao-Dong Wang Department of Gastrointestinal Surgery West China HospitalSichuan UniversityChengdu 610041Sichuan ProvinceChina Department of Clinical Medicine West China School of MedicineSichuan UniversityChengdu 610207Sichuan ProvinceChina

BACKGROUND Malignant atrophic papulosis is a rare and potentially lethal thrombo-occlusive microvasculopathy characterized by cutaneous papules and gastrointestinal *** precise pathogenesis of this disease remains *** SUMMARY We describe the case of a 67-year-old male patient who initially presented with cutaneous aubergine papules and dull pain in the *** week after symptom onset,he was admitted to the hospital for worsening abdominal *** laparotomy showed patchy necrosis and subserosal white plaque lesions on the small intestinal wall,along with multiple *** examination of the small intestine showed extensive hyperemia,edema,necrosis with varying degrees of inflammatory reactions in the small bowel wall,small vasculitis with fibrinoid necrosis and intraluminal thrombosis in the *** on the mentioned evidence,a diagnosis of malignant atrophic papulosis was *** also present the case of a 46-year-old man with known cutaneous manifestations,abdominal pain,nausea and *** physical examination showed positive rebound tenderness.A computed tomography scan revealed free intraperitoneal *** required surgical intervention on admission and then developed an esophageal *** ultimately died of a massive *** In previously published cases of this disease,the cutaneous lesions initially appeared as small erythematous ***,the papules became porcelain-white atrophic depression lesions with a pink,telangiectatic peripheral *** one of the patients,the cutaneous lesions appeared as aubergine *** other patient developed multiple perforations in the gastrointestinal *** to malignant atrophic papulosis affecting multiple organs,many authors speculated that it is not a specific *** case series serves as additional evidence for our hypothesis.

关键词： Malignant atrophic papulosis Gastrointestinal perforation Papulosis Thrombo-occlusive microvasculopathy Case report

A Static Spectrum Aggregation Algorithm in Cognitive Radio System

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Journal of Harbin Institute of Technology(New Series) 2013年第2期20卷 40-44页

作者： Cong Yin Xue-zhi Tan Lin Ma xiu-Hua Li Communication Research Center Harbin Institute of Technology Science and Technology on Information Transmission and Dissemination in Communication Networks Laboratory

Cognitive radio ( CR) is known as an intelligent technology allowing a secondary user ( SU) to occupy a primary user's ( PU's) band when it is idle. Appearance of the idle band may be contiguous or non-contiguous. In other words,the PU's band and the idle band are distributed alternately over the spectrum. Apparently the non-contiguous idle band cannot be fully utilized in this context. This paper proposes an algorithm to solve the problem of low utilization of the non-contiguous idle band and to increase the number of the SU who needs access to the spectrum by a static spectrum aggregation ( SSA) method combined with non-contiguous orthogonal frequency division multiplexing ( NC-OFDM) . The simulation results show that the SSA algorithm realizes at least 70% utilization of the idle band which provides access to the spectrum for as many as 30 SUs as expected.

关键词： cognitive radio static spectrum aggregation non-contiguous OFDM