Effect of Ar dilution flow rate on LPCVD a boron-doped carbon coating from BCl3-C3H6-H2-Ar mixtures

Yongsheng Liu,Litong Zhang,Laifei Cheng,Wenbin Yang,Yongdong Xu 한양대학교 세라믹연구소 2009 Journal of Ceramic Processing Research Vol.10 No.3

A boron-doped carbon coating was deposited from a BCl3-C3H6-H2-Ar system by LPCVD. The effects of the Ar dilution flow rate on deposition rates, morphologies, compositions and bonding states were investigated. Deposition rates were almost the same, about 250 nm/h with different Ar dilution flow rate. Surface morphologies were also almost the same. The flat conchoidal aspect of the fracture surface transformed to a laminated structure with an increase in the Ar dilution flow rate. The carbon concentration was above 76.3 at.%, and the boron concentration was less than 17.9 at.%. The boron concentration increased with an increase in the Ar dilution flow rate, corresponding to a decreasing carbon concentration. The main bonding state of boron was B-sub-C and BC2O. The whole deposition process was dominated by a PyC formation reaction, which led to almost the same deposition rate with different Ar dilution flow rates. A boron-doped carbon coating was deposited from a BCl3-C3H6-H2-Ar system by LPCVD. The effects of the Ar dilution flow rate on deposition rates, morphologies, compositions and bonding states were investigated. Deposition rates were almost the same, about 250 nm/h with different Ar dilution flow rate. Surface morphologies were also almost the same. The flat conchoidal aspect of the fracture surface transformed to a laminated structure with an increase in the Ar dilution flow rate. The carbon concentration was above 76.3 at.%, and the boron concentration was less than 17.9 at.%. The boron concentration increased with an increase in the Ar dilution flow rate, corresponding to a decreasing carbon concentration. The main bonding state of boron was B-sub-C and BC2O. The whole deposition process was dominated by a PyC formation reaction, which led to almost the same deposition rate with different Ar dilution flow rates.

Coupled Patterns Between Fields of Dynamic Height and Bottom Pressure in the Japan/East Sea

Yongsheng Xu,D. Randolph Watts,Mark Wimbush 한국해양과학기술원 2009 Ocean science journal Vol.44 No.1

Vertical coupling between shallow and deep mesoscale eddy processes in the southwestern Japan/East Sea is investigated using acoustic travel-time and bottom pressure measurements from a two-year deployment of an array of pressure-gauge-equipped inverted echo sounders. Canonical correlation analysis is applied to the simultaneously measured data to extract the coupled modes. The upper layer exhibits a migration of the Ulleung Warm Eddy, and correspondingly the deep potential vorticity in the Ulleung Basin adjusts in magnitude and sense to conserve potential vorticity. Coupling between meanders of strong upper currents and abyssal flows has been observed previously in the Gulf Stream during the Synoptic Ocean Prediction experiment. The evidence from our study strongly suggests that such coupling occurs also under much weaker flows. Vertical coupling between shallow and deep mesoscale eddy processes in the southwestern Japan/East Sea is investigated using acoustic travel-time and bottom pressure measurements from a two-year deployment of an array of pressure-gauge-equipped inverted echo sounders. Canonical correlation analysis is applied to the simultaneously measured data to extract the coupled modes. The upper layer exhibits a migration of the Ulleung Warm Eddy, and correspondingly the deep potential vorticity in the Ulleung Basin adjusts in magnitude and sense to conserve potential vorticity. Coupling between meanders of strong upper currents and abyssal flows has been observed previously in the Gulf Stream during the Synoptic Ocean Prediction experiment. The evidence from our study strongly suggests that such coupling occurs also under much weaker flows.

Bioaugmentation with GFP-Tagged Pseudomonas migulae AN-1 in Aniline-Contaminated Aquifer Microcosms: Cellular Responses, Survival and Effect on Indigenous Bacterial Community

( Yongsheng Zhao ),( Dan Qu ),( Rui Zhou ),( Yunge Ma ),( Hao Wang ),( Hejun Ren ) 한국미생물 · 생명공학회 2016 Journal of microbiology and biotechnology Vol.26 No.5

The recently isolated aniline-degrading bacterium Pseudomonas migulae AN-1 was tagged with green fluorescent protein (GFP) to investigate its bioaugmentation potential against anilinecontaminated groundwater through microcosm experiments. The survival and cellular response of GFP-tagged AN-1 introduced in a lab-scale aquifer corresponded directly with aniline consumption. During the process, the GFP-tagged AN-1 biomass increased from 7.52 × 105 cells/ml to 128 × 105 cells/ml and the degradation rate of aniline was 6.04 mg/l/h. GFP-tagged AN-1 was moderately hydrophobic (41.74%-47.69%) when treated with 20- 100 mg/l aniline and exhibited relatively strong hydrophobicity (55.25%-65.78%) when the concentration of aniline was ≥100 mg/l. The membrane permeability of AN-1 increased followed by a rise in aniline below 100 mg/l and was invariable with aniline above 100 mg/l. Pyrosequencing analysis showed that the relative abundance of Proteobacteria (accounted for 99.22% in the non-bioaugmentation samples) changed to 89.23% after bioaugmentation with GFP-tagged AN-1. Actinobacteria increased from 0.29% to 2.01%, whereas the abundance of Firmicutes barely changed. These combined findings demonstrate the feasibility of removing aniline in aquifers by introducing the strain AN-1 and provide valuable information on the changes in the diversity of dominant populations during bioaugmentation.

Parallel task scheduling under multi-Clouds

( Yongsheng Hao ),( Mandan Xia ),( Na Wen ),( Rongtao Hou ),( Hua Deng ),( Lina Wang ),( Qin Wang ) 한국인터넷정보학회 2017 KSII Transactions on Internet and Information Syst Vol.11 No.1

In the Cloud, for the scheduling of parallel jobs, there are many tasks in a job and those tasks are executed concurrently on different VMs (Visual machines), where each task of the job will be executed synchronously. The goal of scheduling is to reduce the execution time and to keep the fairness between jobs to prevent some jobs from waiting more time than others. We propose a Cloud model which has multiple Clouds, and under this model, jobs are in different lists according to the waiting time of the jobs and every job has different parallelism. At the same time, a new method-ZOMT (the scheduling parallel tasks based on ZERO-ONE scheduling with multiple targets) is proposed to solve the problem of scheduling parallel jobs in the Cloud. Simulations of ZOMT, AFCFS (Adapted First Come First Served), LJFS (Largest Job First Served) and Fair are executed to test the performance of those methods. Metrics about the waiting time, and response time are used to test the performance of ZOMT. The simulation results have shown that ZOMT not only reduces waiting time and response time, but also provides fairness to jobs.

Model for Predicting Resilient Modulus of Unsaturated Subgrade Soils in South China

Yongsheng Yao,Jianlong Zheng,Junhui Zhang,Junhui Peng,Jue Li 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.6

Subgrade soils are often unsaturated and the resilient modulus (MR) of subgrade soils is usually subjected to the climate environment andtraffic loading in the field. Therefore, the Matric Suction (MS) and traffic loading are considered to be two important parametersassociated to the MR prediction model. To verify the MR prediction model, the MS of the typical subgrade soil were determined throughthe pressure plate test. In this study, the soil-water characteristic curves were also described using the Fredlund & Xing’s model. Then,the dynamic MR of the typical subgrade soil under various stresses and water contents was measured. After that, a new prediction modelwas proposed with the model variables including the minimum bulk stress, octahedral sheer stress and matric suction, and the validity ofthe new model was verified by previous research results. Finally, the correlations between the physical properties of subgrade soilsincluding the percentage passing through the No. 200 sieve (0.075 mm), plasticity index, liquid limit, dry density and the regressioncoefficients of the new model were established. The results show that the new model can be used to predict the MR well, and it effectivelysolves the problem that the bulk stress is equal with a different combinations of the confining pressure and deviator stress. At the sametime, the MR can be predicted much more easily with physical parameters of subgrade soils rather than conducting triaxial tests.

Magnetic alignment of MnBi crystals and magnetic properties of MnBi-Bi composites

Yongsheng Liu,Jincang Zhang,Zhongming Ren,Shixun Cao,Xiaoyong Zhang,Guangqiang Jia,Kang Deng,Xi Li,Junxi Zhang 한국물리학회 2007 Current Applied Physics Vol.7 No.5

Below Curie temperatureTC, MnBi crystals are aligned alongc-axis in a Bi matrix under a fabrication eldHfof 0.5 T. AboveTC,this alignment is also accomplished by quenching under a highHfof 10 T. Such a method has a prominent feature that MnBi crystalsgrow preferentially and congregate along theHfdirection. Magnetic testing shows a pronounced anisotropy in magnetization in direc-tions normal and parallel toHf, resulting from the alignment. In the case of the alignment belowTC,Hfincreases the transition temper-ature of spin-reorientation and the change in magnetization.

Research on Mobile E-business Security Model based on WPKI Technology and its Application

Yongsheng Luo 보안공학연구지원센터 2015 International Journal of Security and Its Applicat Vol.9 No.7

Information has become the important and strategic resource, and social informatization has become the developing trend and core. The information safety will play an extremely important role in the information society. It is directly related to the national security, business and the normal life. Wireless Public Key Infrastrcture(WPKI) is a technology of wireless networks security, which is applied to transform the E-Business and the Internet for shopping, banking and transacting with one another in anywhere at anytime by using the wireless devices of mobile phone, PDA, IPAD and so on. Wireless application protocol (WAP) can ensure the secure e-business services and wireless applications. So the structure, principle, security infrastructure, application model and environment of WPKI are described in detail. Then the mobile E-business security model based on WPKI Technology is proposed in this paper. It will analyze and demonstrate how the WPKI technology can provide the security services to mobile E-business with similar security requirements and provide the reader with a high level technical application of the WPKI technology. And a application system provided an excellent example for demonstrating the effectiveness, and the secrecy, identity authentication and non repudiation are studied and analyzed.

Frequency and magnetic properties in the range of 10 kHz to 100 MHz for nanocrystal Fe -Co alloy

Yongsheng Liu,Jincang Zhang,Liming Yu,Guangqiang Jia,Yufeng Zhang,Xinyan Wang,Shixun Cao 한국물리학회 2004 Current Applied Physics Vol.4 No.5

Fe-based soft magnetic alloy with Co-doping was fabricated by high-energy milling. The X-ray diraction (XRD) results exhibita single phased structure,which could be regarded as BCC-like FeCo solid solution,was formed. Moreover,it has also been demonstrated that a nanocrystalline FeCo alloy was obtained and the evaluated grain sizes were about 712 nm. The frequency dependence of the initial permeability and magnetic losses,as well as DC-magnetization measurements,was systematically studiedthen. The results show that thefn (fn is the frequency when the curve of the No.n sample has a minimum value) shifts to the higherfrequency with the increasing Co content in the range of 10 kHz to 100 MHz,while the magnetic losses of the samples decrease withthe increasing Co content at the high frequency (800 kHz to 20 MHz). The Co-doping increases the cut-o frequencies of thesamples and makes the initial permeability to keep a constant value in a wider frequency range. The corresponding peak value of theinitial permeability as function of Co-doping concentration turns to the region of low Co concentration. For the long milling time,the loss apparently decreases beyond 1 MHz.

Recovery of Bisphenol A by pH-Triggered Magnetic Nanoparticles

Yongsheng Jia,Enze Li,Zhiping Du,Jianfeng Li,Fangqin Cheng 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2019 NANO Vol.14 No.5

Bisphenol A is not only one of the frequent contaminants of industrial wastewater, but also one of the main ingredients in polycarbonate and epoxy resins. This study synthesizes a pH-triggered Fe3O4@mSiO2@DPDES adsorbent for recycling Bisphenol A through adsorption–desorption process. Due to the strong π–π interaction between the phenyl groups in diphenyldiethoxysilane modified magnetic nanoparticles (MNPs) and Bisphenol A, absorbance reached 120.17 mg/g at pH 7, allowing the bisphenol A adsorbed to Fe3O4@mSiO2@DPDES to be trivially separated from aqueous solutions with a magnet. Desorption of the adsorbed bisphenol A in aqueous solution occurred at pH 2, allowing an impressive 95% recovery rate. The durability of the Fe3O4@mSiO2@DPDES adsorbent was tested by repeated separation of bisphenol A from an aqueous solution, with the recovery efficiency remaining greater than 85% after five cycles.

Efficient and automated method of collapse assessment

Yongsheng Qi,Qiang Gu,Dong Li 국제구조공학회 2012 Steel and Composite Structures, An International J Vol.13 No.6

Seismic collapse analysis requires efficient and automated method to perform thousands of time history analyses. The paper introduced the advantages of speed and convergence property of explicit method, provided a few techniques to accelerate speed of calculation and developed an automated procedure for collapse assessment, which combines the strong capacity of commercial explicit finite element software and the flexible, intelligent specialties of control program written in FORTRAN language aiming at collapse analysis, so that tedious and heavy work of collapse analysis based on FEMAP695 can be easily implemented and resource of calculation can be made the best use of. All the key commands of control program are provided to help analyzers and engineers to cope with collapse assessment conveniently.