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Simulation of the Power Take-off System for a Heaving Buoy Wave Energy Converter

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Journal of Ocean University of China 2020年第3期19卷 497-504页

作者： CAO Feifei SHI Hongda li Ming DONG Xiaochen li demin College of Engineering Ocean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Ocean Engineering Qingdao 266100China Qingdao Municipal Key Laboratory of Ocean Renewable Energy Qingdao 266100China

The heaving buoy wave energy device is popular for wave conditions with small wave heights and short periods. This paper presents the design of a wave energy converter composed of a gyro buoy, a hydraulic power take-off, and an electricity generation system. The energy accumulators are used to improve the output power with different control strategies. The quantity relations between each component are established using theoretical methods. The simulation model describes the energy conversion and calculates the operation time, energy capacity, and output power of the device under different initial pressures, release pressures, and electric resistances. As a result, the capacity is determined by the electronic load, and the maximum output power can be obtained when the accumulators are turned on and off at the same time. This study investigates the factors influencing the electric energy production and can be used to guide the optimization of this type of device.

关键词： wave energy heaving buoy power-take-off accumulator output power

Effects of soil amendments, foliar sprayings of silicon and selenium and their combinations on the reduction of cadmium accumulation in rice

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Pedosphere 2022年第4期32卷 649-659页

作者： demin li Hongyan liU Min GAO Jing ZHOU Jun ZHOU College of Agriculture Guizhou UniversityGuiyang 550025China Key Laboratory of Soil Environment and Pollution Remediation Institute of Soil ScienceChinese Academy SciencesNanjing 210008China University of Chinese Academy of Sciences Beijing 100049China National Engineering and Technology Research Center for Red Soil Improvement Red Soil Ecological Experiment StationChinese Academy of SciencesLiujiazhan PlantationYingtan 335211China

Agricultural soil contamination by cadmium (Cd) is becoming one of the most serious environmental issues and public concerns. In this study, factorial arrangements of treatments were designed to explore the effects of two soil amendments, sodium sulfide-biofuel ash (SSBA) and lime (0.1%), and three foliar applications, silicon (Si, 2.5 mmol L-1), selenium (Se, 40 mg L-1), and their combination (SS), on Cd reduction in rice (Oryza sativa L.) in a pot experiment, which were then verified in a field experiment. Compared with the control without amendment but with spraying of deionized water, both SSBA and lime significantly reduced concentrations of CaCl2-extractable Cd in soil by 30%–39% and 31%–40% and Cd in brown rice by 44%–63% and 53%–72% in the pot and field experiments, respectively. Foliar Si, Se, and SS applications significantly reduced Cd accumulation in brown rice by 62%–64%, 72%–83%, and 39%–73%, respectively, increased rice grain yield, and improved antioxidant enzyme activities in rice leaves but with different trends in the pot and field experiments. Combinations of SSBA and lime with Si, Se, and SS had a non-significant synergistic effect on Cd reduction in brown rice compared to only foliar spraying or soil amendment in both pot and field experiments, although SSBA + Se and SSBA + Si reduced Cd concentration in brown rice by 16%–34% and 14%–24% compared to only foliar Si and Se and soil SSBA applications, respectively. Soil lime application and foliar Si spraying were the most cost-effective strategies to reduce Cd accumulation in brown rice in the field and pot experiments, respectively. Although soil amendments and foliar treatments were individually effective, their combinations failed to generate a significant synergistic reduction of Cd concentration in brown rice.

关键词： antioxidant enzyme activity bioconcentration factor cadmium bioavailability rice yield soil contamination synergistic effect translocation factor

D-Tree Approach to Constructing Overlapping Location-Dependent Data Regions

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Tsinghua Science and Technology 2005年第Z1期10卷 824-829页

作者： LAI liju li demin ZHANG Fan ZHU Ying XU Hao College of Information Science and Technology Donghua University Shanghai 200051 China College of Information Science and Technology Donghua University Shanghai 200051 China College of Information Science and Technology Donghua University Shanghai 200051 China College of Information Science and Technology Donghua University Shanghai 200051 China College of Information Science and Technology Donghua University Shanghai 200051 China

For the past few years, there has been an explosion in the number of individuals carrying wireless devices that are capable of conducting location-dependent information services (LDISs) and provide information based on locations specified in the queries. This paper examines the user's demand of vague queries, and then proposes system architecture of LDISs. In particular, based on D-tree index structure, it takes the method of membership function in fuzzy set theory to provide a more user-oriented approach to constructing overlapping location-dependent data regions, called complementary void overlapping data regions. This structure, carrying more information with less additional storage, brings balance between perceived usefulness and responsiveness, energy consumption, and bandwidth contention in wireless communications. The simulations show that this method is more flexible and practical in practice.

关键词： location-dependent information services (LDISs) index structure complementary void overlapping

首发精神分裂症患者血清乙酰胆碱酯酶、miR-137表达与PANSS评分的相关性分析

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首都食品与医药 2024年第5期31卷 10-13页

作者：刘义宁李德敏邢晓天杨利芹天津市安定医院天津300000

目的探究血清乙酰胆碱酯酶及微小RNA-137(miR-137)表达与首发精神分裂症患者阳性与阴性症状量表(PANSS)评分的相关性.方法选取天津市安定医院120例首发精神分裂症患者作为首发精神分裂症组,另选取同期在该院体检显示健康者120例作为... 详细信息

目的探究血清乙酰胆碱酯酶及微小RNA-137(miR-137)表达与首发精神分裂症患者阳性与阴性症状量表(PANSS)评分的相关性.方法选取天津市安定医院120例首发精神分裂症患者作为首发精神分裂症组,另选取同期在该院体检显示健康者120例作为健康对照组.检测血清乙酰胆碱酯酶及miR-137表达水平,比较治疗前后首发精神分裂症患者血清乙酰胆碱酯酶及miR-137表达水平与PANSS评分相关性.结果首发精神分裂症组患者血清乙酰胆碱酯酶(9.83±2.76)U/mL表达水平明显高于健康对照组(5.21±1.54)U/mL(P<0.05),miR-137(0.57±0.18)表达水平明显低于健康对照组的(1.02±0.31)(P<0.05).治疗4周后,首发精神分裂症组患者PANSS总分、阴性症状评分、一般精神病理评分与血清乙酰胆碱酯酶水平呈正相关(P<0.05),与miR-137表达水平呈负相关(P<0.05).治疗前后,首发精神分裂症组患者血清乙酰胆碱酯酶与miR-137表达水平均呈负相关(P<0.05).结论血清乙酰胆碱酯酶表达水平与PANSS总分、阴性症状评分、一般精神病理评分有关,可反映首发精神分裂症患者治疗效果.

关键词：乙酰胆碱酯酶微小RNA-137 首发精神分裂症阳性与阴性症状量表

Clinical significance of germline copy number variation in susceptibility of human diseases

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Journal of Genetics and Genomics 2018年第1期45卷 3-12页

作者： liwen Hu Xinyue Yao Hairong Huang Zhong Guo Xi Cheng Yang Xu Yi Shen Biao Xu demin li Department of Cardiothoracic Surgery Jinling Hospital School of Clinical Medicine Nanjing University Institute of Laboratory Medicine Jinling Hospital School of Clinical Medicine Nanjing University

Germline copy number variation （CNV） is considered to be an important form of human genetic poly- morphisms. Previous studies have identified amounts of CNVs in human genome by advanced technologies, such as comparative genomic hybridization, single nucleotide genotyping, and high-throughput sequencing. CNV is speculated to be derived from multiple mechanisms, such as nonallelic homologous recombination （NAHR） and nonhomologous end-joining （NHEJ）. CNVs cover a much larger genome scale than single nucleotide polymorphisms （SNPs）, and may alter gene expression levels by means of gene dosage, gene fusion, gene disruption, and long-range regulation effects, thus affecting individual phenotypes and playing crucial roles in human pathogenesis. The number of studies linking CNVs with common complex diseases has increased dramatically in recent years. Here, we provide a comprehensive review of the current understanding ofgermline CNVs, and summarize the association of germline CNVs with the susceptibility to a wide variety of human diseases that were identified in recent years. We also propose potential issues that should be addressed in future studies.

关键词： Copy number variation Susceptibility Risk Cancer Neuropsychological disorders

Experimental Study on Interaction Between Degrees of Freedom in a Wave Buoy

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Journal of Ocean University of China 2019年第6期18卷 1256-1264页

作者： HUANG Shuting SHI Hongda CAO Feifei TAN Junzhe CHENG Haixun li demin liU Shangze GONG Haoxiang TAO Ji College of Engineering Ocean University of ChinaQingdao 266100China Shandong Provincial Key Laboratory of Ocean Engineering Qingdao 266100China

Increasing degrees of freedom(DOFs)is a useful way to raise the power capture efficiency of oscillating wave energy ***,this study proposes a buoy with three DOFs,which are surge,heave,and *** hydrodynamic performance and power capture efficiency of the buoy is physically *** of unidirectional and coupled motions are compared to analyze the interaction effect between freedoms under conditions with and without power take-off *** capture width ratio and corresponding growth rates are also *** show that the buoy makes a periodic sinusoidal(or approximate)movement in every *** effect can cause an increase in the amplitude in one DOF and a decrease in the amplitudes of the *** phenomenon shows that the kinematic energy of the buoy redistributes to all DOFs compared with the unidirectional *** DOFs can improve the power absorption of the buoy in most cases,but the number of DOFs is not the more the better.

关键词： wave energy oscillating buoy multiple degrees of freedom

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抗氧化剂对铁沟浇注料性能影响的研究

耐火与石灰 2024年第2期49卷 6-9页

作者：王文寰张宏进杨强李德民杨连弟河北国亮新材料股份有限公司唐山063000 华北理工大学河北省无机非金属材料重点实验室唐山063000

介绍了以棕刚玉、活性氧化铝、水泥、硅微粉、球沥青为主要原料制备了ASC(Al_(2)O_(3)-SiC-C)铁沟浇注料,研究不同抗氧化剂对浇注料各性能的影响。结果表明:对于抗氧化性及高温抗折强度,抗氧化剂DT1400N效果好于碳化硼粉,碳化硼粉好于... 详细信息

介绍了以棕刚玉、活性氧化铝、水泥、硅微粉、球沥青为主要原料制备了ASC(Al_(2)O_(3)-SiC-C)铁沟浇注料,研究不同抗氧化剂对浇注料各性能的影响。结果表明:对于抗氧化性及高温抗折强度,抗氧化剂DT1400N效果好于碳化硼粉,碳化硼粉好于碳化硅微粉,碳化硅微粉好于325目金属硅粉和200目金属硅粉;对于常温抗折强度、耐压强度,碳化硅微粉、碳化硼粉及DT1400N的效果相当,325目金属硅粉和200目金属硅粉稍差;对于中高温抗折强度、耐压强度,由于抗氧化能力的提高,坯体因氧化疏松而减轻,抗氧化剂DT1400N效果好于碳化硼粉,碳化硼粉好于碳化硅微粉,碳化硅微粉好于金属硅粉。根据试验研究结果,添加新型抗氧化剂DT1400N的铁沟浇注料,其使用效果最佳。

关键词：抗氧化剂铁沟浇注料抗氧化性抗折强度耐压强度

Channel Characteristics Based on Ray Tracing Methods in Indoor Corridor at 300 GHz

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Journal of Donghua University(English Edition) 2021年第3期38卷 221-230页

作者： ZHAI Kai ZHAI Menglin ZHANG Lei li demin College of Information Science and Technology Donghua UniversityShanghai 201620China Engineering Research Center of Digitized Textile and Apparel Technology Ministry of Education Donghua University Shanghai 201620 China

With the rapid development of communication technology,people's demand for ultra-high-speed wireless links becomes higher,among which terahertz spectra are considered as one of the most promising *** this paper,we analyze the channel characteristics at 300 GHz in indoor corridor based on ray tracing methods,including the large-scale and small-scale fading *** results show that it is suitable for short distance transmission due to its large path loss(PL).Firstly,compared with line-of-sight(LoS),the correlation of frequency components in non-line-of-sight(NLoS)is much better,but LoS has more abundant circle angular spread(CAS).Then,a stochastic model is well derived to describe the distance-dependent behaviour of root-mean-square delay spread(RMS-DS)as well as root-mean-square CAS(RMS-CAS).Besides,we find that the channel capacity can effectively increase by increasing the transmitted power in both LoS and ***,it can be seen that the RMS-DS can be significantly reduced in LoS and the channel capacity can increase by changing the position of the *** simulation results will provide references for future indoor communication.

关键词： terahertz channel characteristic ray tracing indoor corridor

引入抗氧化剂CaB_(6)-SiC对ASC浇注料性能的影响

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耐火与石灰 2024年第5期49卷 7-10页

作者：宋利宽张连进李德民杨强涂军波河北国亮新材料股份有限公司唐山063000 华北理工大学河北省无机非金属材料重点实验室唐山063000

铁沟浇注料是高炉炼铁用耐材的重要组成部分,目前影响铁沟浇注料使用寿命的一个重要指标是抗氧化性能,浇注料一旦被氧化,不仅内部碳源失去原有的抗侵蚀作用,而且会产生较多气孔,导致材料致密度和强度的大幅下降。为了改进铁沟浇注料的... 详细信息

铁沟浇注料是高炉炼铁用耐材的重要组成部分,目前影响铁沟浇注料使用寿命的一个重要指标是抗氧化性能,浇注料一旦被氧化,不仅内部碳源失去原有的抗侵蚀作用,而且会产生较多气孔,导致材料致密度和强度的大幅下降。为了改进铁沟浇注料的抗氧化性能,试验了新型抗氧化剂CaB_(6)-SiC对浇注料抗氧化性和其他性能的影响。结果显示:随抗氧化剂CaB_(6)-SiC引入量的增多,试样的抗氧化性能(脱碳层厚度表征)明显增强,常温强度逐渐下降,中温及高温处理后强度指标先增大后下降,线变化率逐渐增大,高温抗折强度先增后降。当抗氧化剂CaB_(6)-SiC引入量达1%时,浇注料试样可以得到最好的综合指标。

关键词：铁沟浇注料抗氧化剂脱碳层线变化率高温抗折强度