Extraction, Distribution, and Precipitation Mechanism of TiN–MnS Complex Inclusions in Al-Killed Titanium Alloyed Interstitial Free Steel

Shuai Gao,Min Wang,Jian‑long Guo,Hao Wang,Jian‑guo Zhi,Yan‑ping Bao 대한금속·재료학회 2021 METALS AND MATERIALS International Vol.27 No.5

The TiN–MnS complex inclusions in Al-killed titanium alloyed interstitial free steel were extracted from the slabs using anelectrolytic aqueous solution method. Scanning electron microscopy with energy spectroscopy analysis and an automaticscanning electron microscope were employed to analyze the size and distribution of TiN–MnS inclusions in the thicknessdirection of the slab. It was found that TiN–MnS complex inclusions were primarily concentrated in the 1/4 thickness directionfrom the inner and outer surfaces, and the size of the complex inclusions in the slab center was approximately 8 μm.TiN began to precipitate when the solidification rate reached 0.646–0.680 in the δ phase, and MnS would appear in the γphase when the solidification rate exceeded 0.450 through thermodynamic analysis. Also, the formation mechanism of thecomplex TiN–MnS was investigated under a crystal structure during solidification.

Response surface analysis of energy balance and optimum condition for torrefaction of corn straw

Shuai Guo,Tiankuo Guo,Deyong Che,Hongpeng Liu,Baizhong Sun 한국화학공학회 2022 Korean Journal of Chemical Engineering Vol.39 No.5

Corn straw has potential as a biofuel, and is generated in large amounts globally. However, this potentialremains underutilized, and torrefaction is one of the processes that can be implemented to improve the energy grade ofthis biomass. In this study, three process parameters (temperature, heating rate, residence time) were investigated usinga response surface method to optimize the torrefaction process of corn straw. At 242.26 oC, a 60 min residence time,and 6.28 oC/min heating rate, the mass yield and higher heating value (HHV) reached their maximum values. Temperaturewas the most important factor influencing torrefaction, followed by residence time and then heating rate. Thegas and liquid by-products were measured by mass spectrometry and mass spectrometry-gas chromatography, and theheat demand of torrefaction was measured by thermogravimetric analysis-differential scanning calorimetry. The HHVof the by-products changed little before 240 oC but increased considerably as the temperature further increased. TheHHV at 242 oC was 1,273 kJ/kg. When the heat loss was 50%, 242 oC was the critical point of energy balance, and afterthat the torrefaction process was energy self-sufficient. These findings provide data to support the establishment ofsemi-industrial or industrial corn straw torrefaction devices.

Effects of sludge pyrolysis temperature and atmosphere on characteristics of biochar and gaseous products

Shuai Guo,Xiaoyan Xiong,Deyong Che,Hongpeng Liu,Baizhong Sun 한국화학공학회 2021 Korean Journal of Chemical Engineering Vol.38 No.1

In view of the importance of inert-atmosphere sludge pyrolysis for effective waste recycling and carbon emission reduction, this study probed the effects of temperature (300-700 oC) and atmosphere (100% N2, 10 CO2/90% N2, or 100% CO2) on the properties of biochar and gases obtained by sludge pyrolysis in a horizontal tube furnace. The emissions of NO, SO2, H2S, and CO increased with increasing temperature, as the inhibitory effect of CO2 on the formation of these gases (observed at <500 oC) concomitantly weakened and was superseded by the reaction of CO2 with carbon at higher temperature to afford gaseous products. The specific surface area (SBET) and pore volume of the biochar produced in the presence of CO2 increased with increasing temperature up to 500 oC, while at higher temperatures the inhibitory effect of CO2 on pore structure development resulted in a decreased SBET and an increased macropore content. These results show that pyrolysis is an effective treatment method for sludge; it can remove 48% N and 50% S in sludge and mitigate the emission of polluting gases. When CO2 participates in the pyrolysis reaction, the SBET of biochar increases significantly. In general, sludge biochar has the potential to be applied as fuel and as an adsorbent.

애니메이션 엔딩타이틀 의미작용 연구

곽수(Shuai Guo),김세화(Sehwa Kim) 한국애니메이션학회 2011 한국애니메이션학회 학술대회지 Vol.2011 No.10

The Prognostic Value of Treatment-Related Lymphopenia in Nasopharyngeal Carcinoma Patients

Li-Ting Liu,Qiu-Yan Chen,Lin-Quan Tang,Shan-Shan Guo,Ling Guo,Hao-Yuan Mo,Ming-Yuan Chen,Chong Zhao,Xiang Guo,Chao-Nan Qian,Mu-Sheng Zeng,Jin-Xin Bei,Jing Tan,Shuai Chen,Ming-Huang Hong,Jian-Yong Shao 대한암학회 2018 Cancer Research and Treatment Vol.50 No.1

Purpose This study was conducted to evaluate the prognostic value of treatment-related lymphopenia in patients with nasopharyngeal carcinoma (NPC). Materials and Methods A total of 413 consecutive stage II-IVb NPC patients treated with concurrent chemoradiotherapy (CCRT) were enrolled. The overall survival (OS), progression-free survival (PFS), and distant metastasis-free survival (DMFS) were calculated with the Kaplan-Meier method, and differences were compared using the log-rank test. Results A minimum (mini)–absolute lymphocyte counts (ALC) of < 390 cells/μL or ALC after 3 months of CCRT (post3m-ALC) < 705 cells/μL was significantly associated with worse outcome than mini-ALC ! 390 cells/μL (OS, p=0.002; PFS, p=0.005; DMFS, p=0.004) or post3m-ALC ! 705 cells/μL (OS, p < 0.001; PFS, p < 0.001; DMFS, p=0.001). Patients with lymphopenia (mini-ALC < 390 cells/μL and post3m-ALC < 705 cells/μL) had a worse prognosis than those without lymphopenia (mini-ALC ! 390 cells/μL and post3m-ALC ! 705 cells/μL) (OS, p < 0.001; PFS, p < 0.001; DMFS, p < 0.001). Multivariate analysis revealed that post3m-ALC was an independent prognostic factor for OS (hazard ratio [HR], 1.76; 95% confidence interval [CI], 1.12 to 2.78; p=0.015), PFS (HR, 1.86; 95% CI, 1.23 to 2.82; p=0.003), and DMFS (HR, 1.87; 95% CI, 1.13 to 3.08; p=0.014). Multivariate analysis also revealed that patients with lymphopenia had a high risk of death (HR, 3.79; 95% CI, 1.75 to 8.19; p=0.001), disease progression (HR, 2.93; 95% CI, 1.59 to 5.41; p=0.001), and distant metastasis (HR, 3.89; 95% CI, 1.67 to 9.10; p=0.002). Multivariate analysis performed with time dependent Cox regression demonstrated ALC was an independent prognostic factor for OS (HR, 0.995; 95% CI, 0.991 to 0.999; p=0.025) and PFS (HR, 0.993; 95% CI, 0.988 to 0.998; p=0.006). Conclusion Treatment-related lymphopenia was a poor prognostic factor in NPC patients.

Sliding Mode Observer Design for Discrete Nonlinear Time-delay Systems with Stochastic Communication Protocol

Shuai Chen,Jun Guo,Lifeng Ma 제어·로봇·시스템학회 2019 International Journal of Control, Automation, and Vol.17 No.7

In this paper, the network-based sliding mode observer is investigated for a class of discrete nonlineartime-delay systems with stochastic communication protocol. The stochastic communication protocol is adopted toregulate the transmission order of the measurements from multiple sensor nodes, which could effectively avoid datacollisions. Under the scheduling of communication protocol, only one sensor node is allowed to get access to theshared communication network at each time step for data transmission. Moreover, the stochastic communicationprotocol is governed by a Markov chain, which converts the protocol-constrained system into a Markovian jumpsystem. It is the purpose to design a sliding mode observer such that, with the stochastic communication protocol,the trajectories of the estimation error system are driven into a band of the sliding surface and, in subsequent time,the sliding motion is mean-square asymptotically stable. By solving a minimization problem, the sufficient conditions for the desired sliding mode observer are established. Finally, an illustrative example is given to demonstratethe effectiveness of the proposed algorithm.

Design and Analysis of Fast Image Encryption Algorithm based on Multiple Chaotic Systems in Real-time Security Car

Shuai Wang,Wei Sun,Yinan Guo,Haiqun Yang,Shuming Jiang 보안공학연구지원센터 2013 International Journal of Security and Its Applicat Vol.7 No.6

Rolling Bearing Incipient Fault Detection via Optimized VMD Using Mode Mutual Information

Shuai Tan,Aimin Wang,Hongbo Shi,Lei Guo 제어·로봇·시스템학회 2022 International Journal of Control, Automation, and Vol.20 No.4

The complete failure of the rolling bearing is a deterioration process from the incipient weak fault to the severe fault, thus it is important to alarm when the incipient fault appear. This work presents a novel incipient bearing fault diagnosis framework using mode mutual information (MMI) based fitness function, variational mode decomposition (VMD), and cuckoo search (CS) algorithm. MMI based fitness function is proposed in order to obtain the optimal combinations of the VMD parameters. Therefore, the optimal parameters of VMD can be obtained by CS algorithm using proposed fitness function. Afterwards, a vibration signal is decomposed into a set of modes using the optimal VMD, and the kurtosis value of all modes are calculated. The envelop of the mode with maximum kurtosis value between modes and raw signal is computed as the input vector of the stacked denoised autoencoder (SDAE). Comparisons have been conducted via SDAE to evaluate the performance by using EMD and the fixedparameter VMD. The experimental results demonstrate that the proposed method is more effective in extracting the incipient bearing fault characteristics.

Highly efficient and selective extraction of minor bioactive natural products using pure ionic liquids: Application to prenylated flavonoids in licorice

Shuai Ji,Yujie Wang,Shikai Gao,Xian Shao,Wei Cui,Yan Du,Mengzhe Guo,Daoquan Tang 한국공업화학회 2019 Journal of Industrial and Engineering Chemistry Vol.80 No.-

Lots of minor constituents in herbal medicines have shown great potential to devolve into leadcompounds, and their extraction is attracting more and more attention in pharmaceutical industry. Thisstudy provided an example that showed efficient and selective extraction of minor bioactive naturalproducts (prenylatedflavonoids with anti-cancer activities) from an herbal medicine (licorice) using pureionic liquids as green solvents. After investigation of a variety of hydrophobic ionic liquids withultrasonic-assisted extraction, we found that [C8MIM]BF4 (1-octyl-3-methylimidazolium tetrafluor-oborate) was the most effective one for extraction offive representative compounds (isoangustone A,glycycoumarin, licoisoflavanone, licoricidin and glabridin), and solvent to solid ratio, extraction time,extraction temperature and soaking time were then optimized through single-factor experiments andresponse surface methodology. As a result, the established method had significantly higher extractionselectivity than conventional organic solvents, which could be attributed to significant physical change oflicorice microstructures after extraction, as well as strong interactions (especially hydrogen bondinteractions) between [C8MIM]BF4 and prenylatedflavonoids by mechanism study. In addition, 78.92% ofthe extracted prenylatedflavonoids could be readily recovered from [C8MIM]BF4 by using reversed-phasesolid phase extraction, and the recyclability of [C8MIM]BF4 was also confirmed.

Electrostatic self‑assembly cellulose nanofibers/MXene/nickel chains for highly stable and efficient seawater evaporation and purification

Shuai Yang,Cai Shi,Keqi Qu,Zhe Sun,Handong Li,Benbin Xu,Zhanhua Huang,Zhanhu Guo 한국탄소학회 2023 Carbon Letters Vol.33 No.7

Seawater evaporation and purification powered by solar energy are considered as a promising approach to alleviate the global freshwater crisis, and the development of photothermal materials with high efficiency is imminent. In this study, cellulose nanofiber (CNF)/MXene/Ni chain (CMN) aerogels were successfully synthesized by electrostatic force and hydrogen bond interaction force. CMN10 achieved a favorable evaporation rate as high as 1.85 kg m? 2 h? 1 in pure water, and the corresponding evaporation efficiency could be up to 96.04%. Even if it is applied to seawater with multiple interference factors, its evaporation rate can still be 1.81 kg m? 2 h? 1. The superior seawater evaporation activity origins from the promoted separation of photoexcited charges and photothermal conversion by the synergy of Ni chain and MXene, as well as the water transport channel supported by the 3D structure frame of CNF. Most importantly, CMN aerogel can maintain water vapor evaporation rates above 1.73 kg m? 2 h? 1 under extreme conditions such as acidic (pH 2) and alkaline (pH 12) conditions. In addition, various major ions, heavy metals and organic pollutants in seawater can be rejected by CMN10 during desalination, and the rejection rates can reach more than 99.69%, ensuring the purity of water resources after treatment. This work shows the great potential of CMN aerogel as a high-efficiency solar evaporator and low-cost photothermal conversion material. Cellulose nanofiber (CNF)/MXene/Ni chain (CMN) aerogels demonstrated high evaporation of water from sea water.