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Grassmannian precoding MU-MIMO scheme

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The Journal of China Universities of Posts and Telecommunications 2008年第3期15卷 105-109,117页

作者： FANG shu li li-hua ZHANG Ping Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

In this article, a Grassmannian precoding multiuser multiple-input multiple-output （MU-MIMO） scheme for downlink transmission is proposed. The proposed MU-MIMO scheme will perform scheduling and precoding simultaneously at the base station, to obtain both the multiuser diversity gain and the precoding gain, to maximize the system capacity. The precoding method is related to Grassmannian precoding, which extends the point-to-point single-user Grassmannian precoding to point-to-multipoint multiuser Grassmannian precoding. It provides further significant system capacity enhancement than the single user MIMO （SU-MIMO） system and also outperforms the block dia^onalization （BD） algorithm under the same simulation environment.

关键词： multiuser MIMO cochannel interference Grassmannian precoding

Non-dimensional analysis of static bifurcation in a natural circulation loop

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Nuclear Science and Techniques 2006年第1期17卷 61-64页

作者： TONG li-li li Tian-shu li Xiao-Yan Department of Nuclear Science and System Engineering Shanghai Jiaotong University Shanghai 200030 China

The steady-state characteristics of a two-phase natural circulation loop were investigated based on the homogenous model. Transcendental equations of non-dimensional loop mass flow rate under various conditions were also derived. The static bifurcation diagram of a two-phase natural circulation described with non-dimensional vari-ables Npch-m + was obtained. In addition, various steady-state characteristics of a natural circulation loop were ana-lyzed and discussed. These characteristics include the existence of multiple solutions under certain conditions, and the maximum mass flow rate. The authors also examined the effects of important parameters such as sub-cooling number, riser-to-heated-region length ratio, and riser-to-heated-region diameter ratio.

关键词：静态分歧自然循环回路双相自然循环非空间分析

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一种铝合金壳体压铸模具设计

铸造 2024年第2期73卷 220-223页

作者：孙全喜李淑利王伟石智成田迎春尹飞刘辉李金桃中国兵器工业集团第五二研究所内蒙古包头014034 陆军装备部驻南京地区军事代表局驻烟台地区山东烟台264000 杭锦旗能源服务中心内蒙古鄂尔多斯017400

通过对壳体零件的结构和成形性分析,重点对模具设计的主要环节进行了详细的分析与研究;分析设计了模具的分型面位置、浇注和排溢系统的结构以及推出机构,采用在侧面厚壁处多点浇口的结构形式;对模具的型芯、型腔做了具体的结构设计,采... 详细信息

通过对壳体零件的结构和成形性分析,重点对模具设计的主要环节进行了详细的分析与研究;分析设计了模具的分型面位置、浇注和排溢系统的结构以及推出机构,采用在侧面厚壁处多点浇口的结构形式;对模具的型芯、型腔做了具体的结构设计,采用型腔在定模、型芯在动模的普通两板式结构形式;并且型芯和型腔部分制作成活动镶件,便于修理、更换,模具结构简单、实用,完全满足模具的设计要求。

关键词：壳体零件模具设计多点浇口两板式设计要求

Intervention of laser periphery iridectomy to posterior iris bowing in high myopic eyes

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Chinese Medical Journal 2012年第24期125卷 4466-4469页

作者： WANG Hong-tao WANG Ning-li li shu-ning Beijing Tongren Eye Center Beijing Tongren Hospital Capital Medical University Beijing Ophthalmology and Visual Science Key Laboratory Beijing 100730 China

Background For some high myopic patients with posterior iris bowing, laser periphery iridectomy should be performed pre-operation to prevent pupil block glaucoma if these patients would have phakic intraocular lens implantation to correct high myopia. So we had the opportunity to analysis the influence of laser iridectomy on posterior iris bowing. Methods Eighteen high myopic patients with posterior iris bowing （11 males and 7 females） were involved in the study in Beijing Tongren Eye Center from March 2008 to July 2008. Phakic intraocular lens were implanted to correct their ametropia. The mean age was （32＋6） years （range, 25-40 years）. The center anterior chamber depth, the pupil diameter, the posterior iris bowing depth and the anterior chamber angle were measured with anterior segment coherence tomography （AS-OCT） under the normal condition, myosis condition induced by 2% pilocarpine, laser periphery iridectomy after myosis, and 2% pilocarpine eluting condition respectively. Results There was no significant difference of center anterior chamber depth under the four conditions （P=0.512）. The pupil constricted after pilocarpine （P=0.001）. After＇ laser iridectomy performed and pilocarpine eluted, posterior iris bowing depth reduced more than that in normal condition （P=0.003）. The anterior chamber angle reduced significantly after laser periphery iridectomy and pilocarpine eluted （P=0.012）. Conclusion Laser periphery iridectomy can reduce the posterior iris bowing, which might be due to the change in aqueous circulate pathway.

关键词： myopia posterior iris bowing laser iridectomy

Differentiation of hepatocytoid cell induced from whole-bone-marrow method isolated rat myeloid mesenchymal stem cells

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World Journal of Gastroenterology 2006年第30期12卷 4866-4869页

作者： Wei li Su-Nan liu Duan-De Luo Lei Zhao ling-Lan Zeng shu-ling Zhang shu-li li Department of Infectious Disease Union Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430022 Hubei Province China

AIM： To explore the expansion and differentiation of hepatocytoid cell induced from myeloid mesenchymal stem cell （MSC） in vib＇o, in order to find suitable resource of hepatocytes for bioartiflcial liver or liver transplantation. METHODS： The rat myeloid MSC was isolated and divided into three groups which were cultured by Friedensteion method, and then were induced by culture fluid, culture fluid plus cholestatic serum and culture fluid plus hepatocyte growth factor （HGF）, respectively. Hepatocytoid cell as well as expression of CK18 and AFP was observed by immunohistochemistry. RESULTS： After the induction for 21 d, hepatocytoid cell was observed, and its expression of CK18 and AFP was detected by immunohistochemistry in MSC cultured with cholestatic serum. Furthermore, on the 35^th d, albumin mRNA was expressed in the cell, suggesting the inducing effect was similar to that by HGF.CONCLUSION： Rat myeloid MSC can differentiate into hepatocyte lineage under appropriate condition. This method is easy to operate.

关键词： Mesenchyme stem cell Hepatocytoid cell Expansion Differentiation Induction

A high li-ion diffusion kinetics in multidimensional and compact-structured electrodes via vacuum filtration casting

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Journal of Energy Chemistry 2024年第6期93卷 368-376,I0010页

作者： Jieqiong li Ting Ouyang Lu liu shu Jiang Yongchao Huang M.-Sadeeq Balogun College of Materials Science and Engineering Hunan Joint International Laboratory of Advanced Materials and Technology for Clean EnergyHunan UniversityChangsha 410082HunanChina Institute of Environmental Research at Greater Bay Key Laboratory for Water Quality and Conservation of the Pearl River DeltaMinistry of EducationGuangzhou UniversityGuangzhou 510006GuangdongChina

Manufacturing process,diffusion co-efficient and areal capacity are the three main criteria for regulating thick electrodes for lithium-ion batteries(liBs).However,simultaneously regulating these criteria for liBs is desirable but remains a significant *** this work,niobium pentoxide(Nb_(2)O_(5))anode and lithium iron phosphate(liFePO_(4))cathode materials were chosen as the model materials and demonstrate that these three parameters can be simultaneously modulated by incorporation of micro-carbon fibers(MCF)and carbon nanotubes(CNT)with both Nb_(2)O_(5) and LFP via vacuum filtration *** as-prepared MNC-20 anode and MLC-20 cathode achieves high reversible areal capacity of≈5.4 m A h cm^(-2)@0.1 C and outstanding li-ion diffusion coefficients of≈10~(-8)cm~2 s~(-1)in the half-cell *** assembled MNC-20‖MLC-20 full cell liB delivers maximum energy and power densities of244.04 W h kg^(-1)and 108.86 W kg^(-1),*** excellent electrochemical properties of the asprepared thick electrodes can be attributed to the highly conductive,mechanical compactness and multidimensional mutual effects of the MCF,CNT and active materials that facilitates rapid li-ion diffusion ***,electrochemical impedance spectroscopy(EIS),symmetric cells analysis,and insitu Raman techniques clearly validates the enhanced li-ion diffusion kinetics in the present architecture.

关键词： Thick electrodes Carbon nanotubes li-ion diffusion co-efficient Vacuum filtration technique High areal capacity lithium-ion batteries

Mineral constituents of a prized edible mushroom(Tricholoma matsutake)and soils beneath the fruiting bodies from the production areas across China

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Journal of Mountain Science 2016年第11期13卷 2046-2052页

作者： li Qiang li shu-hong HUANG Wen-li liU Cheng-yi XIONG Chuan li Xiao-lin ZHENG lin-yong Soil and Fertilizer Institute Sichuan Academy of Agricultural SciencesChengdu 610066China Biotechnology&Germplasm Resources Institute Yunnan Academy of Agricultural SciencesKunming 650221China Institute of Biological&Nuclear Technology Sichuan Academy of Agricultural SciencesChengdu 610066China Sichuan Panzhihua Academia of Agriculture and Forestry Panzhihua 617061China

Fruiting bodies(500 g per site) of Tricholoma matsutake and the surface layer of soils collected from 20 spatially distant areas with pristine backgrounds across China were analyzed for potassium,magnesium,calcium,zinc,iron,copper,manganese and cadmium using inductively coupled plasma optical emission *** terms of the bioconcentration and bioexclusion concept,K,Mg,Zn,and Cu were highly bioconcentrated,and their bioconcentration factor values varied between 75-615,2-107,38-603 and 7-76,respectively,across the 20 ***,Mn and Cd were moderately bioconcentrated and their bioconcentration factors(BCFs) varied between 0.6-34.0,0.4-37.0 and 0.9-7.0 ***,Ca was excluded(BCF<1).*** is a species that is harvested in the wild as a valuable food and can contain a wide spectrum of both essential and hazardous mineral compounds that accumulate at elevated concentrations even if grown in pristine *** estimated intake rate of Cd in the fruiting bodies indicates cause for concern associated with this metal resulting from the daily consumption of between 200 and 400 g of fruiting bodies on a frequent basis during the mushrooming season.

关键词： Fungi Heavy metals Mineral composition Mushrooms Wild food

Analysis of Essential Oils from Flower-buds, Leaves and Stems of Filipendula palmata(Pall.) Maxim.

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Chemical Research in Chinese Universities 2005年第6期21卷 658-662页

作者： WU Yin MENG Xiang-ying liU Xiao-hua BAO Yong-li WANG shu-ping li Yu-xin Institute of Genetics and Cytology Northeast Normal University Changchun 130024 P. R. China

The essential oils of the flower-buds, leaves and stems of Filipendula palmata（ Pall. ） Maxim. were analyzed by GC and GC-MS. Thirty-three, forty-seven and forty-seven compounds in the flower-buds, leaves and stems were identified, respectively. Methyl salicylate exists in a great amount which is up to 70. 10% in the flower-buds. Its amount is also high in other two parts. The data obtained show that it may be one of the main natural mosquito-expelling and pain-alleviating components in the three parts. The flower-buds are the main active part with the mosquito-expelling function.

关键词： Filipendula palmata( Pall. ) Maxim. Essential oil GC-MS

Photosynthetic response dynamics in the invasive species Tithonia diversifolia and two co-occurring native shrub species under fluctuating light conditions

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Plant Diversity 2024年第2期46卷 265-273页

作者： Ju li shu-Bin Zhang Yang-Ping li CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglunMengla 666303YunnanChina University of Chinese Academy of Sciences Beijing 100049China

To determine the invasiveness of invasive plants,many studies have compared photosynthetic traits or strategies between invasive and native ***,few studies have compared the photosynthetic dynamics between invasive and native species during light *** compared photosynthetic induction,relaxation dynamics and leaf traits between the invasive species,Tithonia diversifolia and two native species,Clerodendrum bungei and Blumea balsamifera,in full-sun and shady *** photosynthetic dynamics and leaf traits differed among *** showed a slower induction speed and stomatal opening response but had higher average intrinsic water-use efficiency than the two native species in full-sun ***,the slow induction response may be attributed to the longer stomatal length in *** had a significant effect on photosynthetic dynamics in *** and *** but not in *** shady habitat,*** had a faster photosynthetic induction response than in full-sun habitat,leading to a higher average stomatal conductance during photosynthetic induction in *** than in the two native *** contrast,*** had a larger stomatal length and slower photosynthetic induction and relaxation response in shady habitat than in full-sun habitat,resulting in higher carbon gain during photosynthetic ***,in both habitats,*** had an overall higher carbon gain during light fluctuations than the two native *** results indicated that *** can adopt more effective response strategies under fluctuating light environments to maximize carbon gain,which may contribute to its successful invasion.

关键词： Invasive plant Photosynthetic induction Photosynthetic relaxation Carbon gain Stomatal traits Tithonia diversifolia