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Effect of Seasonality on Distribution of Macroalgae in a Stream System(Xin'an Spring) in Shanxi Province,North China

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Journal of Integrative Plant Biology 2006年第8期48卷 889-896页

作者： bian-fang hu shu-lian xie School of Life Science and Technology Shanxi University Taiyuan 030006 China

A survey of the seasonal distribution of macroalgae in a stream system in Shanxi Province, north China, was undertaken from July 2004 to April 2005. The relative abundance and percentage cover of macroalgae, and several environmental factors were monitored along a 20-m stretch at each of four sites, at intervals of approximately three months （one sampling per season）. Several stream conditions were relatively constant over the sampling period （pH, maximum width and maximum depth）, whereas others exhibited a distinct seasonal pattern （water temperature and specific conductance）, and some fluctuated with no discernable seasonal pattern （current velocity and dissolved oxygen）. Forty-two species of macroalgae were found, with a predominance of Chlorophyta （26 species, 61.9%）. Rhodophyts and Charophyta represented the smallest proportion （1 species each, 2.38%）. Six macroalgae species were the most widespread, occurring in all four sampling sites. Twelve species were found at only one site each. In terms of seasonality, eight species occurred throughout the year, whereas 16 species were found in only one season each. The macroalgal community at Xin＇an Spring was species rich relative to other streams. Species richness per sampling site was negatively correlated with pH. Principal component analysis revealed that no single variable had much influence on the macroalgal seasonal dynamics. We calculated Sorensen similarity indices to compare our study with other continent-wide surveys of stream macroalgae, but the similarity indices were all very low. This study also shows that macroalgae in different locations have significant reproductive isolation.

关键词： China distribution environmental factors seasonality stream macroalgae.

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Comparative Study of Single-phase Phase-locked Loops for Grid-connected Inverters Under Non-ideal Grid Conditions

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CSEE Journal of Power and Energy Systems 2022年第1期8卷 155-164页

作者： Jinming Xu Hao Qian Shenyiyang bian Yuan hu Shaojun xie Nanjing University of Aeronautics and Astronautics Nanjing 211106China

In renewable power generation systems,ensuring the synchronization of the inverter and the power grid is crucial for the stable operation of grid-connected ***,the phase-locked loop(PLL)technology has become a widely used grid synchronization method because of its simple implementation and robustness under various grid *** though a lot of PLLs have been proposed,an overview and comparative analysis of multiple PLLs can be helpful for practical *** addition,the weak grid condition is a great challenge for the ***,this study first presents an overview of the existing PLLs together with their general structures and basic working *** on the implementation of the phase detector,the PLL can be divided into three categories:power-based PLL(pPLL),orthogonal-signalgenerator-based PLL(OSG-PLL)and adaptive-filter-based PLL(AF-PLL).Then,from the above classification,seven typical single-phase PLLs are selected for further ***,some test results are given,and a comprehensive evaluation of the selected PLLs under different grid conditions is conducted.

关键词： Grid synchronization non-ideal grid condition overview single-phase phase-locked loop(PLL)

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Natural disaster warning system for safe operation of a high-speed railway

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Transportation Safety and Environment 2021年第4期3卷 34-45页

作者： hu Qizhou fang Xin bian Lishuang School of Automation Nanjing University of Science and TechnologyNanjing 210094China

In this paper,the least square support vector machine(LSSVM)is used to study the safety of a high-speed *** to the principle of LSSVM regression prediction,the parameters of the LSSVM are optimized to model the natural disaster early warning of safe operation of a high-speed railway,and the management measures and methods of high-speed railway safety operation under natural disasters are *** relevant statistical data of China’s high-speed railway are used for training and *** experimental results show that the LSSVM can well reflect the nonlinear relationship between the accident rate and the influencing factors,with high simulation accuracy and strong generalization ability,and can effectively predict the natural disasters in the safe operation of a high-speed ***,the early warning system can improve the ability of safety operation evaluation and early warning of high-speed railway under natural disasters,realize the development goals of high-speed railway(safety,speed,economic,low-carbon and environmental protection)and provide a theoretical basis and technical support for improving the safety of a high-speed railway.

关键词： high-speed railway safe operation natural disaster early warning system least square support vector machine(LSSVM)

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Clinical outcomes of amniotic membrane loaded with5-FU PLGA nanoparticles in experimental trabeculectomy

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International Journal of Ophthalmology(English edition) 2015年第1期8卷 29-34页

作者： fang hu Xiang-Yun Zeng Zhao-lian xie Lin-Lin Liu liang huang Department of Ophthalmology the First Affiliated Hospital of Gannan Medical University

AIM: To evaluate the effect of amniotic membrane loaded with 5-fluorouracil poly(lactic-co-glycolic acid)(PLGA) nanoparticles(5-FU-NPs) in the surgical outcomes of experimental trabeculectomy in ***: Thirty-two New Zealand white rabbits were randomly categorized into four groups with 8 rabbits in each group. Group 1, the control group, performed traditional trabeculectomy without adjuvant *** the experimental groups performed compound trabeculectomy with different implantations including amniotic membrane(group 2), 5-FU-NPs(group 3) and amniotic membrane loaded with 5-FU-NPs(group 4).Clinical evaluations including IOP measurement and filtration bleb analysis were performed in all groups ***: There is no significant difference of mean IOP in all groups at first 7d after surgery. While at P14,mean IOPs of experimental group 2(9.8 ±2.1 mm Hg),groups 3(8.9 ±2.8 mm Hg) and group 4(7.6 ±2.3 mm Hg)were significantly reduced compared to control group(12.4 ±2.6 mm Hg; n =8, P <0.05). At P21, mean IOPs of groups 3(11.7±3.2 mm Hg) and group 4(9.9±1.6 mm Hg)were significantly decreased compare to control group(17.9±1.6 mm Hg) and group 2(16.6 ±2.8 mm Hg; n =8,P <0.05). At P28, mean IOPs of groups 3(13.8±3.3 mm Hg)and group 4(10.6 ±2.0 mm Hg) were also significantly reduced compare to control group(19.4±2.3 mm Hg) and group 2(18.5 ±2.4 mm Hg; n =8, P <0.05). Meanwhile mean IOP of group 4 is significantly decreased compared to group 3 at P28(n =8, P <0.05). Survival analysis of functional filtration blub in all groups revealed the longest survival time in group 4(24.9±5.1d) compared to that in group 3(20.6 ±4.3d), group 2(15.0 ±5.2d) and control group(10.1±5.7d).CONCLUSION: Amniotic membrane loaded with 5-FuNPs may function as an effective anti-scarring implant and provides improved long-term surgical outcomes for experimental trabeculectomy in rabbits.

关键词： 5-fluorouracil trabeculectomy polyactic acid nanoparticles amniotic membrane

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Significance of serum glucagon-like peptide-1 and matrix Gla protein levels in patients with diabetes and osteoporosis

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World Journal of Clinical Cases 2022年第5期10卷 1527-1535页

作者： Fei-Fei xie Yu-fang Zhang Yan-fang hu Yun-Yun xie Xiao-Ying Wang shu-Zhen Wang Bao-Qiang xie Department of Endocrinology Guangdong Provincial People’s Hospital Ganzhou Hospital(Ganzhou Municipal Hospital)Ganzhou 341000Jiangxi ProvinceChina

BACKGROUND Osteoporosis is a systemic bone disease characterized by decreased bone mass,impaired bone mass,and reduced bone strength that leads to increased bone fragility and *** 2 diabetes mellitus(T2DM)complicated with osteoporosis is a common systemic metabolic bone disease,and reduced bone mass and bone strength are considered the main clinical features;however,the pathogenesis of this disease has not been fully *** occurrence is considered related to sex,age,and genetic *** are many risk factors for diabetes complicated with ***,exploring these risk factors will help prevent *** To investigate the relationships among serum glucagon-like peptide-1(GLP-1)levels,matrix Gla protein(MGP)levels,and diabetes with *** Sixty patients with T2DM complicated with osteoporosis confirmed by the endocrinology department of our hospital were selected as the case *** T2DM patients with bone loss were selected as the control *** healthy participants were selected as the healthy *** general data,bone mineral density index,and bone metabolic markers of the three groups were *** relationships among GLP-1 levels,MGP levels,and the bone mineral density index of the case group were analyzed using linear correlation analysis and a logistic regression *** Differences in sex,smoking,and drinking among the case group,control group,and healthy group were not statistically significant(P>0.05).The mean age of the case group was older than those of the control and healthy groups(P<0.05).The body mass index,fasting plasma glucose level,HbA1c level,hypertension rate,and coronary heart disease rate of the case and control groups were higher than those of the healthy group(P<0.05).The serum GLP-1 and MGP levels of the case group were lower than those of the control and healthy groups;these differences were statistically significant(P<0.05).The serum GLP-1 and MGP levels of the control gr

关键词： Glucagon-like peptide-1 Matrix Gla protein Diabetes mellitus Osteoporosis Bone mineral density Systemic bone disease

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CFD predictions of LBO limits for aero-engine combustors using fuel iterative approximation

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Chinese Journal of Aeronautics 2013年第1期26卷 74-84页

作者： hu Bin huang Yong Wang fang xie Fa Key Laboratory of Light-duty Gas-turbine Institute of Engineering Thermophysics Chinese Academy of Sciences AEL Key Laboratory of Science and Technology for National Defence School of Energy and Power EngineeringBeihang University

Lean blow-out （LBO） is critical to operational performance of combustion systems in propulsion and power generation. Current predictive tools for LBO limits are based on decadesold empirical correlations that have limited applicability for modern combustor designs. According to the Lefebvre＇s model for LBO and classical perfect stirred reactor （PSR） concept, a load parameter （LP） is proposed for LBO analysis of aero-engine combustors in this paper. The parameters contained in load parameter are all estimated from the non-reacting flow field of a combustor that is obtained by numerical simulation. Additionally, based on the load parameter, a method of fuel iterative approximation （FIA） is proposed to predict the LBO limit of the combustor. Compared with experimental data for 19 combustors, it is found that load parameter can represent the actual combustion load of the combustor near LBO and have good relativity with LBO fuel/air ratio （FAR）. The LBO FAR obtained by FIA shows good agreement with experimental data, the maximum prediction uncertainty of FIA is about ±17.5%. Because only the non-reacting flow is simulated, the time cost of the LBO limit prediction using FIA is relatively low （about 6 h for one combustor with computer equipment of CPU 2.66 GHz · 4 and 4 GB memory）, showing that FIA is reliable and efficient to be used for practical applications.

关键词： Aero-engine combustor Computational fluid dynamics Fuel iterative approximation LBO limits prediction Perfect stirred reactor

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Formation mechanism of solid product produced from co-pyrolysis of Pingdingshan lean coal with organic matter in huadian oil shale

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Frontiers of Chemical Science and Engineering 2021年第2期15卷 363-372页

作者： Xiangchun Liu Jun hu Ruilun xie Bin fang Ping Cui Anhui Key Laboratory of Coal Clean Conversion&Utilization Anhui Province Key Laboratory of Coal Clean Conversion and High Valued UtilizationSchool of Chemistry and Chemical EngineeringAnhui University of TechnologyMa’anshan 243032China

A mixture of Pingdingshan lean coal and acid-treated huadian oil shale was co-pyrolyzed in a drop-tube fixed-bed reactor in the temperature range of 300℃–450℃.To reveal the formation mechanism of the solid co-pyrolysis product,changes in some physicochemical properties were investigated,using analysis by X-ray diffraction,X-ray photoelectron spectroscopy,scanning electron microscopy,pore analysis,thermogravimetry,and electron spin resonance.X-ray diffraction showed that the lattice plane spacing for the co-pyrolyzed mixture decreased from 0.357 nm to 0.346 nm and the average stacking height increased from 1.509 nm to 1.980 nm in the temperature range of 300°C–450°C,suggesting that pyrolysis treatment increased its degree of *** amount of oxygen-containing functional groups and pore volume decreased with increasing *** and electron spin resonance results showed that synergistic effects occurred during the co-pyrolysis process.A formation mechanism for the solid product was ***-rich radicals generated from the pyrolysis of the oil shale were trapped by hydrogen-poor macromolecular radicals of the intermediate metaplast produced from coal pyrolysis,thereby increasing the yield of solid product.

关键词： co-pyrolysis coal oil shale electron spin resonance mechanism

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Visible and Ultraviolet Reflectivity of Hg_(0.8)Cd_(0.2)Te

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Chinese Physics Letters 1996年第12期13卷 937-939页

作者： JIANG Run-qing hu xie-rong fang Jia-xiong Infrared and Remote Sensing Research Laboratory Shandong UniversityJi’nan 250100 Shanghai Institute of Technical Physics Chinese Academy of SciencesShanghai 200083

The fundamental reflectivity spectra of Hg_(0.8)Cd_(0.2)Te have been *** feature of the spectra is the presence of E_(1) and E_(2) peaks within the fundamental absorption region.A three dimensional saddle point is used to fit the E_(1) and E_(1)+Δ_(1) critical point and some simulated calculation is done for E_(2) at X *** measured and calculated reflectivities are compared and prominent features of the reflectivity spectra are identified with critical point transition at the and X points in the Brillouin zone.

关键词： reflectivity critical spectra

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Effects of mask wearing duration and relative humidity on thermal perception in the summer outdoor built environment

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Building Simulation 2023年第9期16卷 1601-1616页

作者： Rong hu Jianlin Liu Yongxin xie Jiao Jiao Zhaosong fang Borong Lin College of Environmental Science and Engineering Donghua UniversityShanghaiChina Department of Building Science School of ArchitectureTsinghua UniversityBeijingChina School of Civil Engineering Guangzhou UniversityGuangzhouChina Department of Building Environment and Energy Engineering The Hong Kong Polytechnic UniversityKowloonHong KongChina

During the pandemic,face masks are one of the most significant self-protection necessities,but they also cause heat *** using the ERA5(ECMWF Reanalysis 5th Generation)database and the local weather bureau data,the effect of mask wearing on outdoor thermal sensation has been investigated by a survey conducted in the hot summer and cold winter region of eastern China in the summer of *** show that wearing a face mask for a longer period result in a higher level of discomfort,and the primary source of discomfort is hot and stuffy *** effect of relative humidity is crucial for mask wearers in warm-biased thermal environments,as mean thermal sensation vote(TSV)peaks when environmental relative humidity reaches the range of 70%to 80%and decreases after this range due to the evaporation within the microclimate created by a face ***,prolonged mask wearing increases participants’hot feelings,especially in warm ***,participants wearing face masks for less than 30 min feel hot at a physiological equivalent temperature(PET)value of 34.4℃,but those who wear them for over 60 min express hot feelings even at a PET value of 24.7℃.The participants who wear a face mask while walking slowly outdoors have similar thermal sensations to those who do not wear a mask,but are in a higher activity *** findings demonstrate that mask wearing has a crucial impact on outdoor thermal comfort assessment in a warm-biased outdoor thermal environment.

关键词： outdoor thermal comfort disposable medical masks mask wearing duration relative humidity physiological equivalent temperature(PET)

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Development and Evaluation of a 7-DOF Haptic Interface

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IEEE/CAA Journal of Automatica Sinica 2018年第1期5卷 261-269页

作者： Jian-Long Hao Xiao-liang xie Gui-Bin bian Zeng-Guang Hou Xiao-hu Zhou Key Laboratory of Management and Control for Complex Systems Institute of Automation University of Chinese Academy of Sciences Beijing 100190 China IEEE

With the development of human robot interaction technologies, haptic interfaces are widely used for 3 D applications to provide the sense of touch. These interfaces have been utilized in medical simulation, virtual assembly and remote manipulation tasks. However, haptic interface design and control are still critical problems to reproduce the highly sensitive touch sense of humans. This paper presents the development and evaluation of a7-DOF(degree of freedom) haptic interface based on the modified delta mechanism. Firstly, both kinematics and dynamics of the modified mechanism are analyzed and presented. A novel gravity compensation algorithm based on the physical model is proposed and validated in simulation. A haptic controller is proposed based on the forward kinematics and the gravity compensation algorithm. To evaluate the control performance of the haptic interface, a prototype has been implemented. Three kinds of experiments: gravity compensation, static response and force tracking are performed respectively. The experimental results show that the mean error of the gravity compensation is less than 0.7 N and the maximum continuous force along the axis can be up to 6 N. This demonstrates the good performance of the proposed haptic interface.

关键词： Dynamic modeling evaluation haptic interface impedance control

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