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Morphology of single inhalable particle in the air polluted city of Shijiazhuang,China

Journal of Environmental Sciences 2008年第4期20卷 429-435页

作者： WANG Zanhong zhang Lingzhi zhang yuliang ZHAO Zhou zhang Sumin College of Resource and Environment Sciences Hebei Normal University Shijiazhuang 050016 China Environmental Monitoring Center of Shifiazhuang Shijiazhuang 050016 China

In the typical air polluted city of Shijiazhuang, single inhalable particle samples in non-heating period, heating period, dust storm days, and snowy days were collected and detected by SEM/EDS （scanning electron microscopy and energy dispersive X-ray spectrometry）. The particle morphology was characterized by the 6 shape clusters, which are： irregular square, agglomerate, sphere, floccule, column or stick, and unknown, by quantitative order. The irregular square particles are common in all kinds of samples; sphere particles are more, and column or stick are less in winter samples; in the wet deposit samples, agglomerate and floccule particles are not found. The surface of most particles is coarse with fractal edge, which can provide suitable chemical reaction bed in the polluted atmospheric environment. New formed calcium crystal is found to demonstrate the existence of neutralized reaction, explaining the reason for the high SO2 emission and low acid rain frequency in Shijiazhuang. The three sorts of surface patterns of spheres are smooth, semi-smooth, and coarse, corresponding to the element of Si-dominant, Si-Al-dominant, and Fe-dominant, The soot particle is present as floccule with average size around 10 μm, considerably larger than the former reported results, but wrapped or captured with other fine particles to make its appearance unique and enhance its toxicity potentially. The new formed calcium crystal, the 3 sorts of sphere surface patterns, and the unique soot appearance represent the single inhalable particle＇s morphology characteristics in Shijiazhuang City.

关键词： single particle morphology new formed calcium crystal spheres soot

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Computational Analysis of Centrifugal Pump Delivering Solid-liquid Two-phase Flow during Startup Period

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Chinese Journal of Mechanical Engineering 2014年第1期27卷 178-185页

作者： zhang yuliang LI Yi ZHU Zuchao CUI Baoling The State Key Lab of Fluid Power Transmission and Control Zhejiang University College of Mechanical Engineering Quzhou University The Province Key Lab of Fluid Transmission Technology Zhejiang Sci-Tech University

The transient behavior of centrifugal pumps during transient operating periods, such as startup and stopping, has drawn more and more attention recently because of urgent needs in engineering. Up to now, almost all the existing studies on this behavior are limited to using water as working fluid. The study on the transient behavior related to solid-liquid two-phase flow has not been seen yet. In order to explore the transient characteristics of a high specific-speed centrifugal pump during startup period delivering the pure water and solid-liquid two-phase flow, the transient flows inside the pump are numerically simulated using the dynamic mesh method. The variable rotational speed and flow rate with time obtained from experiment are best fitted as the function of time, and are written into computational fluid dynamics （CFD） code-FLUENT by using a user defined function. The predicted heads are compared with experimental results when pumping pure water. The results show that the difference in the transient performance during startup period is very obvious between water and solid-liquid two-phase flow during the later stage of startup process. Moreover, the time for the solid-liquid two-phase flow to achieve a stable condition is longer than that for water. The solid-liquid two-phase flow results in a higher impeller shaft power, a larger dynamic reaction force, a more violent fluctuation in pressure and a reduced stable pressure rise comparing with water. The research may be useful to tmderstanding on the transient behavior of a centrifugal pump under a solid-liquid two-phase flow during startup period.

关键词： centrifugal pump solid-liquid two-phase flow startup transient performance

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HeteroMeth： A Database of Cell-to-cell Heterogeneity in DNA Methylation

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Genomics, Proteomics & Bioinformatics 2018年第4期16卷 234-243页

作者： Qing Huan yuliang zhang Shaohuan Wu Wenfeng Qian State Key Laboratory of Plant Genomics Institute of Genetics and Developmental Biology Chinese Academy of SciencesBeijing 100101China Key Laboratory of Genetic Network Biology Institute of Genetics and Developmental Biology Chinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

DNA methylation is an important epigenetic mark that plays a vital role in gene expression and cell differentiation. The average DNA methylation level among a group of cells has been extensively documented. However, the cell-to-cell heterogeneity in DNA methylation, which reflects the differentiation of epigenetic status among cells, remains less investigated. Here we established a gold standard of the cell-to-cell heterogeneity in DNA methylation based on single-cell bisulfite sequencing （BS-seq） data. With that, we optimized a computational pipeline for estimating the heterogeneity in DNA methylation from bulk BS-seq data. We further built HeteroMeth, a database for searching, browsing, visualizing, and downloading the data for heterogeneity in DNA methylation for a total of 141 samples in humans, mice, Arabidopsis, and rice. Three genes are used as examples to illustrate the power of HeteroMeth in the identification of unique features in DNA methylation. The optimization of the computational strategy and the construction of the database in this study complement the recent experimental attempts on single-cell DNA methylomes and will facilitate the understanding of epigenetic mechanisms underlying cell differentiation and embryonic development. HeteroMeth is publicly available at http：//***/HeteroMeth.

关键词： Cell-to-cell heterogeneity DNA methylation Bisulfite sequencing Single cell Shannon entropy

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Numerical Simulation and Analysis of Solid-liquid Two-phase Flow in Centrifugal Pump

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Chinese Journal of Mechanical Engineering 2013年第1期26卷 53-60页

作者： zhang yuliang LI Yi CUI Baoling ZHU Zuchao DOU Huashu The State Key Lab of Fluid Power Transmission and Control Zhejiang University The Province Key Lab of Fluid Transmission Technology Zhejiang Sci-Tech University

The flow with solid-liquid two-phase media inside centrifugal pumps is very complicated and the relevant method for the hydraulic design is still immature so far. There exist two main problems in the operation of the two-phase flow pumps, i.e., low overall efficiency and severe abrasion. In this study, the three-dimensional, steady, incompressible, and turbulent solid-liquid two-phase flows in a low-specific-speed centrifugal pump are numerically simulated and analyzed by using a computational fluid dynamics （CFD） code based on the mixture model of the two-phase flow and the RNG k-~ two-equation turbulence model, in which the influences of rotation and curvature are fully taken into account. The coupling between impeller and volute is implemented by means of the frozen rotor method. The simulation results predicted indicate that the solid phase properties in two-phase flow, especially the concentration, the particle diameter and the density, have strong effects on the hydraulic performance of the pump. Both the pump head and the efficiency are reduced with increasing particle diameter or concentration. However, the effect of particle density on the performance is relatively minor. An obvious jet-wake flow structure is presented near the volute tongue and becomes more remarkable with increasing solid phase concentration. The suction side of the blade is subject to much more severe abrasion than the pressure side. The obtained results preliminarily reveal the characteristics of solid-liquid two-phase flow in the centrifugal pump, and are helpful for improvement and empirical correction in the hydraulic design of centrifugal pumps.

关键词： centrifugal pump solid-liquid two-phase particle property hydraulic performance abrasion numerical simulation

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Assessment of Agricultural Drought Vulnerability Based on Crop Growth Stages:A Case Study of Huaibei Plain,China

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International Journal of Disaster Risk Science 2023年第2期14卷 209-222页

作者： Yanqi Wei Juliang Jin Haichao Li yuliang Zhou Yi Cui Nii Amarquaye Commey yuliang zhang Shangming Jiang School of Energy and Power Engineering Xihua UniversityChengdu610039China School of Civil Engineering Hefei University of TechnologyHefei230009China Institute of Water Resources and Environmental Systems Engineering Hefei University of TechnologyHefei230009China State Key Laboratory of Hydroscience and Engineering Department of Hydraulic EngineeringTsinghua UniversityBeijing100084China Interdisciplinary Centre for River Basin Environment University of YamanashiKofu400-8510Japan Key Laboratory of Water Conservancy and Water Resources of Anhui Province Water Resources Research Institute of Anhui Province and Huaihe River CommissionMinistry of Water ResourcesHefei230088China

Climate change can lead to and intensify drought *** the vulnerability of disaster-affected elements is significant for understanding the mechanisms that transform drought intensity into eventual *** study proposed a growth-stage-based drought vulnerability index(GDVI)of soybean using meteorological,groundwater,land use,and field experiment data and crop growth model *** CROPGRO-Soybean model was used to simulate crop growth and water *** growth stages were considered since the sensitivity of soybean to drought is strictly related to the growth *** GDVI was applied to the Huaibei Plain,Anhui Province,China,with the goal of quantifying the spatiotemporal characteristics of soybean drought vulnerability in typical years and growth *** results show that:(1)The sensitivity of leaf-related parameters exceeded that of other parameters during the vegetative growth stage,whereas the top weight and grain yield showed a higher sensitivity in the reproductive growth stage;(2)A semi-logarithmic law can describe the relationship between the drought sensitivity indicators and the GDVI during the four growth *** pod-filling phase is the most vulnerable stage for water deficit and with the highest loss upper limit(over 70%);(3)The 2001 and 2002 seasons were the driest time during *** and Huainan Cities were more vulnerable to drought than other regions on the Huaibei Plain in 2001,while Huaibei and Suzhou Cities were the most susceptible areas in *** results could provide effective decision support for the categorization of areas vulnerable to droughts.

关键词： Agricultural drought Drought vulnerability Huaibei plain Soybean growth stages

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Emerging roles and potential clinical applications of translatable circular RNAs in cancer and other human diseases

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Genes & Diseases 2023年第5期10卷 1994-2012页

作者： Hongliang Liu Wenjing Hao Jiao Yang yuliang zhang Xinfang Wang Chunming zhang Shanxi Key Laboratory of Otorhinolaryngology Head and Neck Cancer First Hospital of Shanxi Medical UniversityTaiyuanShanxi 030001China Shanxi Province Clinical Medical Research Center for Precision Medicine of Head and Neck Cancer First Hospital of Shanxi Medical UniversityTaiyuanShanxi 030001China Department of Otolaryngology Head&Neck Surgery First Hospital of Shanxi Medical UniversityTaiyuanShanxi 030001China Department of Cell Biology and Genetics The Basic Medical School of Shanxi Medical UniversityTaiyuanShanxi 030001China Department of Anatomy The Basic Medical School of Shanxi Medical UniversityTaiyuanShanxi 030001China

Circular RNAs (circRNAs) are a special class of single-stranded RNA molecules with covalently closed loops widely expressed in eukaryotic organisms. CircRNAs have long been considered to play important roles in various physiological and pathological processes as non-coding RNAs. However, circRNAs have recently garnered considerable attention due to their ability to be translated into peptides/proteins via internal ribosome entry site- or N6-methyladenosine-mediated pathways or rolling translation mechanisms. Furthermore, dysregulation of translatable circRNAs and their encoded proteins has been associated with developing and progressing diseases such as cancer. This review aims to summarize the driving mechanisms of circRNA translation and the available strategies in circRNA translation research. The main focus is on the emerging biological functions of translatable circRNAs, their regulatory mechanisms, and potential clinical applications in human diseases to provide new perspectives on disease diagnosis, prognosis, and targeted therapy.

关键词： Circular RNA Clinical applications Function Peptide Translation

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A reusable SMA actuated non-explosive lockrelease mechanism for space application

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International Journal of Smart and Nano Materials 2020年第1期11卷 65-77页

作者： Xueting Pan yuliang zhang Yifan Lu Fei Yang Honghao Yue State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbinChina Beijing Spacecraft BeijingChina

After the satellite is launched with the carrier rocket,it is necessary to separate the satellite from the rocket at an appropriate time to ensure that the satellite enters the intended *** this process,it is vital to ensure a reliable connection and accurate *** the increasing use of microsatellite in orbit,the contradiction between the shock of separation and the requirement of the platform’s dynamic environment is becoming increasingly ***,the traditional pyrotechnic separation device can no longer meet the *** paper presents a reusable non-explosive release actuator using shape memory alloy(SMA)wire for high load and low *** system is based on the Fast Acting Shock-less Separation Nut(FASSN)*** the shape memory effect of SMA,a biased SMA wire trigger has been developed,which is used as the driver source of the *** the moment of receiving the electrical signal,the SMA wire generates stress and *** trigger set free the constraints on the mechanical components,and the target is *** results indicate that the trigger device can unlock successfully and well meet the technical objectives.

关键词： SMA actuator non-explosive lock-release space application

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Numerical Calculation of Transient Thermal Characteristics of Nozzle Flowmeter

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Frontiers in Heat and Mass Transfer 2023年第1期21卷 245-264页

作者： Xin Li Shaohan Zheng yuliang zhang Minfeng Lv College of Mechanical Engineering Quzhou UniversityQuzhou324000China College of Mechanical Engineering Zhejiang University of TechnologyHangzhou310023China Zhejiang Zhigao Machinery Co. Ltd.Quzhou324024China

This article aims to reveal the transient thermal characteristics of the solid domain in a nozzle flowmeter when measuring fluids of varying *** on finite element method,the transient numerical calculation of the thermal characteristics of each component of the nozzle flowmeter has been *** research shows that:as the fluid passes through the flowmeter,the high heat flux area inside the nozzle flowmeter gradually transfer from the center of the nozzle to the inlet and outlet,as well as the pressure tapping points upstream and downstream;High thermal stress zones are present near the upstream and downstream pressure tapping points and inlet and outlet area;High thermal deformation zones occur near the upstream and downstream pressure tapping points and eight slot nozzle.

关键词： Nozzle flowmeters numerical calculation transient thermal characteristics

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Growth of Anisotropic Platinum Nanostructures Catalyzed by Gold Seed Nanoparticles

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Nano Research 2008年第3期1卷 249-257页

作者： Zheng Fang yuliang zhang Feifei Du Xinhua Zhong Laboratory for Advanced Materials Department of ChemistryEast China University of Science&TechnologyShanghai 200237China

This paper reports an effective method for the synthesis of platinum nanostructures with anisotropic morphologies by decomposition of platinum dichloride in oleylamine at intermediate temperatures catalyzed by gold seed nanoparticles.A small quantity of spherical gold nanoparticles formed in situ was used to trigger the nucleation and anisotropic growth of the Pt *** varying the amount of gold seed nanoparticles,porous fl ower-like,irregular polyhedron-shaped,multi-branched rod shaped,and caterpillar-like Pt nanostructures were produced in high yields at 190240°C in reaction times of a few *** of morphology under different conditions has been systematically studied and a kinetically controlled induced growth mechanism has been proposed.

关键词： Platinum nanostructure gold seed nanoparticles synthesis

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Experimental Study on a Centrifugal Pump with an Open Impeller during Startup Period

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Journal of Thermal Science 2013年第1期22卷 1-6页

作者： yuliang zhang Zuchao Zhu Yingzi Jin Baoling Cui Yi Li Huashu Dou The State Key Lab of Fluid Power Transmission and Control Zhejiang University The Province Key Lab of Fluid Transmission Technology Zhejiang Sci-Tech University

Transient performance of fluid machinery during transient operating periods, such as startup and stopping, has been drawn more attentions recently due to the growing engineering needs. In this paper, the transient behavior of a prototype centrifugal pump with an open impeller during rapid startup period is studied experimentally. The variations of the rotational speed, flow rate, head, and shaft power during rapid startup period are recorded in ex- periments at different discharge valve openings. In addition, the non-dimensional flow rate and head are also used to analyze the transient behavior. The research result shows that the rise characteristic of the rotational speed is not basically changed by working points, while mainly depends on the startnp characteristics of the driving motor. Compared with the rapid rise of the rotational speed, the flow rate rises slowly in the initial stage of startup. Moreover, the flow rate lags behind the rotational speed to rise to final stable value, and the delay becomes more severe with the increase of the discharge valve opening. The shaft power impact phenomenon generally exists in the process of startup. The non-dimensional analysis shows that the non-dimensional head is very high at the very beginning of startup, and quickly falls to the minimum, then gradually rises to final stable value, while the non-dimensional flow rate always shows the rise tendency during whole startup period. In conclusion, it is found from the non-dimensional results that the quasi-steady analysis is unable to accurately assess the transient flow during startup period.

关键词： centrifugal pump open impeller startup experimental study transient behavior

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