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| 1 | Efficient oxygen reduction reaction by a highly porous,nitrogen-doped carbon sphere electrocatalyst through space confinement effect in nanopores显示文摘A highly porous nitrogen-doped carbon sphere(NPC)electrocatalyst was prepared through the carbonization of biomass carbon spheres mixed with urea and zinc chloride in N_(2) atmosphere.The sample carbonized at.1000℃ demonstrates a superior oxygen reduction reaction(ORR)performance over the Pt/C electrocatalyst,while its contents of pyridinic nitrogen and graphitic nitrogen are the lowest among samples synthesized at the same or lower carbonization temperatures.This unusual result is explained by a space confinement effect from the microporous and mesoporous structures in the microflakes,which induces the further reduction of peroxide ions or other oxygen species produced in the first step reduction to water to have the preferred overall four electron reduction ORR process.This work demonstrates that in addition to the amount or species of its aptive sites,the space confinement can be a new approach to enhance the ORR performance of precious-metal-free,nitrogen-doped carbon electrocatalysts. | Zheyang MO Weiyi YANG Shuang GAO Jian Ku SHANG Yajun DING Wuzhu SUN Qi LI | 2021 | Journal of Advanced Ceramics2021，10，4： | 3 |
| 2 | Candidate microRNA biomarkers in human colorectal cancer: Systematic review profiling studies and experimental validation显示文摘 | YanleiMa PengZhang JianjunYang ZhihuaLiu ZheYang HuanlongQin | 2012 | Int J Cancer2012，，9： | 1 |
| 3 | Influence of silicon cluster on epitaxial growth of silicon carbide显示文摘Precursor concentration dependences of growth rate, doping concentration and surface morphology have been investigated in the epitaxial growth of 4H-SiC(0001) epilayers with horizontal hot-wall CVD system using various precursor concentrations under constant C/Si ratio. Form the experimental data it is found that silicon cluster which is formed through gas phase nucleation plays an important role in controlling the doping concentration and epitaxial growth rate of the silicon carbide. It was observed that the concentration of silicon clusters cannot reach the equilibrium value in the process by using a low SiH 4 concentration, and this phenomenon has not been reported by others. | LI ZheYang LI Yun CHEN Chen HAN Pin | 2011 | Science China(Physics,Mechanics & Astronomy)2011，54，9： | 1 |
| 4 | On the operating speed and energy efficiency of GaN-based monolithic complementary logic circuits for integrated power conversion systems显示文摘Gallium nitride(GaN)-based power conversion systems exhibit striking competitiveness in realizing compact and high-efficiency power management modules.Recently emerging GaN-based p-channel field-effect transistors(FETs)and monolithic integration techniques enable the implementation of GaN-based complementary logic(CL)circuits and thereby offer an additional pathway to improving the system-level energy efficiency and functional-ity.In this article,holistic analyses are conducted to evaluate the potential benefits of introducing GaN CL circuits into the integrated power systems,based on the material limit of GaN and state-of-the-art experimental results.It is revealed that the propagation delay of a single-stage CL gate based on the commercial p-GaN gate power HEMT(high-electron-mobility transistor)platform could be as short as sub-nanosecond,which sufficiently satis-fies the requirement of power conversion systems typically with operating frequencies less than 10 MHz.With the currently adopted n-FET-based logic gates(e.g.,directly coupled FET logic)replaced by CL gates,the power consumption of peripheral logic circuits could be substantially suppressed by more than 10^(3) times,mainly due to the elimination of the pronounced static power loss.Consequently,the energy efficiency of the entire system could be substantially improved. | Zheyang Zheng Han Xu Li Zhang Kevin J.Chen | 2021 | Fundamental Research2021，1，6： | 1 |
| 5 | Epitaxial growth of 4H-SiC on 4* off-axis substrate for power device 显示文摘 | Li Zheyang Han Ping Li Yun | 2011 | Chin Phys Lett2011，28，9： | 1 |
| 6 | Ti/4H-SiC Schottky barrier diodes with field plate and B^+implantation edge termination technology显示文摘 | Chen Gang Li Zheyang Bai Song | 2007 | Chinese journal of Semiconductors2007，28，9： | 1 |
| 7 | Isotope Geochemistry of the Xinchang -Yongjia Silver (Lead-Zinc)Ore Belt in Eastern Zhejiang Province显示文摘In the Xinchang-Yongjia silver (lead-zinc) ore belt, there mainly occur the large to medium-sized Haoshi, Bamao, Dalingkou and Wubu silver deposits or silver-bearing lead-zinc deposits. On the basis of researches on these typical deposits, the mechanism of leaching-drawing mineralization of Mesozoic geothermal water and the related model are put forward in this paper in the light of the time interval between rock and formation ages as well as hydrogen, oxygen, sulphur and lead isotope geochemical characteristics. The major metallogenic process occurred in volcanic rock layers. The ore-forming fluids are geothermal water coming from meteoric water and circulating at shallow layers. This geothermal water leached and absorbed ore-forming materials from its country rocks during its flowing (such metallogenic elements as silver, lead-zinc and sulphur mainly came from consolidated volcanic rocks), leading to the formation of meso - epithermal silver deposits. | Xu Butai, Li Changjiang Zhejiang Institute of Geology and Mineral Resources, Hangzhou, Zhejiangand Chen Haoshou Department of Earth Sciences, Zhejiang U niversity, Hangzhou, Zheyang Liu Xinzhu | 1995 | Acta Geologica Sinica(English Edition)1995，69，1： | 0 |
| 8 | Using Multiple Risk Factors and Generalized Linear Mixed Models with 5-Fold Cross-Validation Strategy for Optimal Carotid Plaque Progression Prediction显示文摘Background Cardiovascular diseases are closely linked to atherosclerotic plaque development and rupture.Plaque progression prediction is of fundamental significance to cardiovascular research and disease diagnosis,prevention,and treatment.Generalized linear mixed models(GLMM)is an extension of linear model for categorical responses while considering the correlation among observations.Methods Magnetic resonance image(MRI)data of carotid atheroscleroticplaques were acquired from 20 patients with consent obtained and 3D thin-layer models were constructed to calculate plaque stress and strain for plaque progression prediction.Data for ten morphological and biomechanical risk factors included wall thickness(WT),lipid percent(LP),minimum cap thickness(MinCT),plaque area(PA),plaque burden(PB),lumen area(LA),maximum plaque wall stress(MPWS),maximum plaque wall strain(MPWSn),average plaque wall stress(APWS),and average plaque wall strain(APWSn)were extracted from all slices for analysis.Wall thickness increase(WTI),plaque burden increase(PBI)and plaque area increase(PAI) were chosen as three measures for plaque progression.Generalized linear mixed models(GLMM)with 5-fold cross-validation strategy were used to calculate prediction accuracy for each predictor and identify optimal predictor with the highest prediction accuracy defined as sum of sensitivity and specificity.All 201 MRI slices were randomly divided into 4 training subgroups and 1 verification subgroup.The training subgroups were used for model fitting,and the verification subgroup was used to estimate the model.All combinations(total1023)of 10 risk factors were feed to GLMM and the prediction accuracy of each predictor were selected from the point on the ROC(receiver operating characteristic)curve with the highest sum of specificity and sensitivity.Results LA was the best single predictor for PBI with the highest prediction accuracy(1.360 1),and the area under of the ROC curve(AUC)is0.654 0,followed by APWSn(1.336 3)with AUC=0.6342.The optimal predictor among all possible combinations for PBI was the combination of LA,PA,LP,WT,MPWS and MPWSn with prediction accuracy=1.414 6(AUC=0.715 8).LA was once again the best single predictor for PAI with the highest prediction accuracy(1.184 6)with AUC=0.606 4,followed by MPWSn(1. 183 2)with AUC=0.6084.The combination of PA,PB,WT,MPWS,MPWSn and APWSn gave the best prediction accuracy(1.302 5)for PAI,and the AUC value is 0.6657.PA was the best single predictor for WTI with highest prediction accuracy(1.288 7)with AUC=0.641 5,followed by WT(1.254 0),with AUC=0.6097.The combination of PA,PB,WT,LP,MinCT,MPWS and MPWS was the best predictor for WTI with prediction accuracy as 1.314 0,with AUC=0.6552.This indicated that PBI was a more predictable measure than WTI and PAI. The combinational predictors improved prediction accuracy by 9.95%,4.01%and 1.96%over the best single predictors for PAI,PBI and WTI(AUC values improved by9.78%,9.45%,and 2.14%),respectively.Conclusions The use of GLMM with 5-fold cross-validation strategy combining both morphological and biomechanical risk factors could potentially improve the accuracy of carotid plaque progression prediction.This study suggests that a linear combination of multiple predictors can provide potential improvement to existing plaque assessment schemes. | Qingyu Wang Dalin Tang Liang Wang Gador Canton Zheyang Wu Thomas SHatsukami Kristen L Billiar Chun Yuan | 2019 | 医用生物力学2019，34，A01： | 0 |
| 9 | Effects of dimethyl ether on soot formation in premixed laminar flame by laser induced incandescence method显示文摘The control of PM emission is a rather complicated problem to be solved both for diesel engine and GDI engines.There are vast factors affecting PM emission,the fuel,A/F,combustion temperature and so on.But undoubtedly,most efforts are paid to exhaust aftertreatment,rather than the control of generation.This paper is to investigate the effect of dimethyl ether(DME,CH3OCH3)on soot generation in flame.Therefore,a laser induced incandescence(LII)measurement system for soot volume concentration measurements in flame is used.Two DME gaseous mixtures were prepared with equivalence ratios 1 and 2.To highlight its effect on soot formation,acetylene known as the precursor of soot,is added in different ratios.Similarly,CO2 is mixed to simulate exhaust gas recycling(EGR)effect in engines.The experimental results indicate that the fuel property and A/F ratio are the dominating factors for the generation of soot during combustion.The combustion of DME doesn't emit soot obviously even under rich mixture condition.When burning the mixture of DME and acetylene(C2H2)in different proportion,there is barely soot emission at equivalence ratio of 1.The soot emission increases as the proportion of C2H2 increases at equivalence ratio 2,and the DME addition reduces the soot emission of C2H2 flame.CO2 dilution doesn't lead to the increase of soot when burning DME at equivalence 1 and 2.Soot emission is lower when the mixture of DME and acetylene is diluted by CO2,though soot volume concentration increases slightly as the proportion of C2H2 increases.The kinetic analysis indicates that the combustion of DME does not produce the precursor of soot.Under fuel-rich combustion conditions,C2H2 reacts with H radical to form C2H3,which leads to soot.When DME is added,it competes for H radical,which reduces the formation of C2H3 and thus reduces soot formation.The research carried out in this paper indicates that DME fuel has obviously power to reduce soot formation during combustion,no matter whether it is diluted by CO2 or mixed with soot precursor substance C2 H2. | Zengqiang Zhu Zheyang Li Chao Liu Xiao Chen Shenghua Liu | 2020 | Journal of Traffic and Transportation Engineering(English Edition)2020，7，3： | 0 |
| 10 | Improving Right Ventricle Cardiac Function for Repaired Tetralogy of Fallot Patient with Contracting Bands: A Modelling Study显示文摘Objective Patients with repaired tetralogy of Fallot(rTOF)account for the majority of cases with late onset right ventricle(RV)failure.The current surgical approach,including pulmonary valve replacement/insertion(PVR),has yielded mixed results with some patients recover RV function and some do not.An innovative surgical approach was proposed to help ventricle to contract and improve RV function qualified by ejection fraction with one or more active contracting bands.Computational biomechanical modelling is a widely used method in cardiovascular study for investigation of mechanisms governing disease development,quantitative diagnostic and treatment strategies and improving surgical designs for better outcome.Muscle active contraction caused by zero-load sarcomere shortening leads to change of zero-load configurations.In lieu of experimenting using real surgery on animal or human,computational simulations(virtual surgery)were performed to test different band combination and insertion options to identify optimal surgery design and band insertion plan.Methods Cardiac magnetic resonance(CMR)data were obtained from one rTOF patient(sex:male,age:22.5 y)before pulmonary valve replacement surgery.The patient was suffering from RV dilation and dysfunction with RV end-systole volume 254.49ml and end-diastole volume 406.91 mL.A total of 15 computational RV/LV/Patch/Band combination models based on(CMR)imaging were constructed to investigate the influence of different band insertion surgery plans.These models included 5 different band insertion models combined and 3 different band contraction ratio(10%,15%and 20%band zero-stress length reduction).These models included 5 different band insertion models:Model 1 with one band at anterior to the middle of papillary muscle;Model 2 with one band at posterior to the middle of papillary muscle;Model 3 with 2 bands which are the ones from Models 1&2 combined;Model 4 with a band at the base of the papillary muscle;Model 5 with 3 bands which is a combination of Models 3&4.A pre-shrink process was performed on in-vivo begin-filling and end-systole MRI data to obtain diastole and systole zero4oad ventricle geometries.An extra 5%-8%shrinkage was applied to obtain corresponding systole zero-load geometry reflecting myocardium sarcomere shortening.The zero-load band length in systole was 10%,15%and 20%shorter than that in diastole according to their corresponding contraction ratio.The nonlinear Mooney-Rivlin model was used to describe the ventricle material properties with their material parameter values adjusted to match measured data with CMR.The band material properties were in the same scale with healthy right ventricle.The RV/LV/Band model construction and solution procedures were the same as described.Results Model 5 with band contraction ratio of 20%has the ability to improve RV ejection fraction to 41.07%,which represented a 3.61%absolute improvement,or 9.6%relative improvement using pre-PVR ejection fraction as the baseline number.The ejection fractions for Models 1-4 with band contraction ratio of 20%were 39.28%,39.47%,38.87%and 40.34%respectively.Compared to models with band contraction ratio15%and 20%,models with band contraction ratio 10%has the least ability on RV ejection fraction improvement with ejection fraction 38.28%,38.00%,38.81%,38.50%and 39.36%corresponding to Models 1-5.Conclusions This pilot work demonstrated that the band insertion surgery may have great potential to improve post-PVR RV cardiac function for patients with repaired TOF.More band contraction ratio and inserted band number may lead to better post-surgery outcome.Further investigations using in-vitro animal experiments and final patient studies are warranted. | Han Yu Tal Geva Rahul HRathod Chun Yang Zheyang Wu Kristen LBilliar Xueying Huang Dalin Tang | 2019 | 医用生物力学2019，34，A01： | 0 |
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