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Chinese Journal of Polymer Science 2018年第5期36卷 675-682页

作者： Jing Liu Hai-Juan Kong yu Ma Shu Zhu Mu-huo yu State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and Engineering Donghua University School of Materials Engineering Shanghai University of Engineering Science Key Laboratory of Shanghai City for Lightweight Composites State Key Laboratory for Modification of Chemical Fibers and Polymer Materials Donghua University

The conventional low-temperature method of solution polycondensation was developed to realize the reaction of p-phenylenediamin and terephthaloyl chloride for the preparation of poly（p-phenylene terephthalamide）（PPTA）. Some main factors influencing this process were investigated to determine the optimum condition for high molecular weight. Experiment showed significant slowing of the reaction and gradual deviation of second-order reaction kinetics due to diffusion control. These phenomena were studied theoretically via dynamic Monte Carlo simulation. A concise expression,n～c0^-0.88·t^0.37, was proposed to describe the diffusioncontrolled polycondensation process as a function of the monomer concentration and reaction time. The theoretical results provided a good description of diffusion-effected kinetics for the polycondensation process of PPTA, and demonstrated good agreement with the experimental data. Some differences of scaling relations between model and experiment results were also discussed.

关键词： Poly(p-phenylene terephthalamide) Molecular weight Reaction kinetics Molecular simulation

Fragmentation study of two brassinolides by ion trap tandem mass spectrometry

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Chinese Science Bulletin 2010年第21期55卷 2219-2224页

作者： huo FeiFeng BAI yu LIU HuWei The Key Lab of Bioorganic Chemistry and Molecular Engineering Ministry of Education Institute of Analytical Chemistry College of Chemistry and Molecular Engineering Peking University Beijing 100871 China

The fragmentation pathways of two isomers of brassinosteroids,28-homobrassinolide(28-h-BL)and 28-epihomobrassinolide(28-eh-BL),have been investigated by tandem mass spectrometry(MSn,n=1,2,3,4)with the electrospray ionization(ESI) *** ESI mass spectrometric fragmentation pathways of protonated 28-h-BL and 28-eh-BL were comprehensively elucidated,and the principles revealed in this investigation could potentially be used to identify and distinguish brassinosteroids and their isomers.

关键词：高油菜素内酯串联质谱法离子阱电喷雾质谱光谱分裂异构体 MSn ESI

Influences of GVD on the characteristics of soliton in a passively mode-locked Er-doped fiber laser

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The Journal of China Universities of Posts and Telecommunications 2013年第6期20卷 117-121页

作者： BAI Bing ZHAO Xiao-hui GUO yu-bin huo Jia-yu College of Communication Engineering Jilin University

In this paper, the characteristics of soliton in a passively mode-locked Er-doped fiber laser modeled by a non-distributed model are numerically investigated with the split-step Fourier method. Based on the analysis and model, sech2-shaped soliton is obtained by controlling the group velocity dispersion （GVD） and small-signal gain of the gain fiber. The law that the dispersion influences the characteristics of soliton in the mode-locked fiber laser is researched in net-cavity averaged anomalous dispersion regime.

关键词： passively mode-locked Er-doped fiber laser optical soliton group velocity dispersion

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International Journal of Automation and computing 2012年第3期9卷 266-273页

作者： huo, Zhen-yu Yang, Zhu Pang, Yan-Jun School of Information Science and Electrical Engineering Hebei University of Engineering Handan 056038 China School of Science Hebei University of Engineering Handan 056038 China Institute of Uncertainty Mathematics Hebei University of Engineering Handan 056038 China

A form of iterative learning control (ILC) is used to update the set-point for the local controller. It is referred to as set-point-related (SPR) indirect ILC. SPR indirect ILC has shown excellent performance: as a supervision module for the local controller, ILC can improve the tracking performance of the closed-loop system along the batch direction. In this study, an ILC-based P-type controller is proposed for multi-input multi-output (MIMO) linear batch processes, where a P-type controller is used to design the control signal directly and an ILC module is used to update the set-point for the P-type controller. Under the proposed ILC-based P-type controller, the closed-loop system can be transformed to a 2-dimensional (2D) Roesser s system. Based on the 2D system framework, a sufficient condition for asymptotic stability of the closed-loop system is derived in this paper. In terms of the average tracking error (ATE), the closed-loop control performance under the proposed algorithm can be improved from batch to batch, even though there are repetitive disturbances. A numerical example is used to validate the proposed results.

关键词： Iterative learning control (ILC) indirect ILC multi-input multi-output (MIMO) 2-dimensional system asymptotical stability linear matrix inequality (LMI).

Behavior of aqueous stable colloidal nano-C60 aggregates exposed to TX100 micelles under different environmental conditions

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Frontiers of Environmental Science & Engineering 2015年第2期9卷 197-205页

作者： Jing huo Ye yu Ling GE Bo ZHANG Yiliang HE School of Environmental Science & Engineering Shanghai Jiaotong University Shanghai 200240 China

C60, as one of carbon nanomaterials widely used in various fields, could be released into the water environment thus exerting some potential health risks to human beings. This work examined the behavior of aqueous stable colloidal nano-C60 （nC60） aggregates under different environmental conditions including Polyethylene glycol octylphenol ether （TX100） micelles concentration, pH, and reaction time when exposed to TX100micelles. Results show that the nC60 aggregates became more dispersive and restored the capability of generating the singlet oxygen when exposed to TX100 micelles. With the increase of TX100 concentration, smaller average size of nC60 aggregates was observed in dynamic light scattering （DLS） analysis, the fluorescence intensity of TX100 was more quenched by nC60 aggregates, and the kinetic rate constant of generating the singlet oxygen for nC60 aggregates was improved. The mean size of nC60 aggregates in the presence of TX 100 had no obvious variations when the pH ranged from 4 to 8. The longer reaction time between nCro aggregates and TX100 led to a higher kinetic rate constant of generating the singlet oxygen. Collective data suggest that variations in physicochemical properties of nC60 aggregates are strongly dependent on the surrounding media under different environmental conditions and directly govern nC60＇S transport behavior and potential toxicity.

关键词： Keywords nano-C60 (nC60) aggregates photochemicalreactivity artificial biological membrane

Simultaneous realization of direct photodeposition and high H_(2)-production activity of amorphous cobalt sulfide nanodot-modified rGO/TiO_(2)photocatalyst

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Rare Metals 2021年第11期40卷 3125-3134页

作者： Feng Chen Hong-Fei Feng Wei Luo Ping Wang huo-Gen yu Jia-Jie Fan School of Chemistry Chemical Engineering and Life SciencesWuhan University of TechnologyWuhan 430070China State Key Laboratory of Silicate Materials for Architectures Wuhan University of TechnologyWuhan 430070China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450002China

To realize highly efficient hydrogen production of graphene-based photocatalysts,it is greatly important to increase more interfacial active sites onto *** this work,the highly efficient CoS_(x)-rGO(reduced graphene oxide)/TiO_(2) composite photocatalyst was synthesized via a simple two-step method,including the hydrothermal loading of rGO nanosheets onto TiO_(2) nanoparticles and the subsequent photodeposition process of CoS_(x) nanodots(0.5-2 nm) on the rGO *** experimental results confirmed that the CoS_(x)-rGO/TiO_(2) photocatalyst displayed a distinctly higher photocatalytic H_(2)-evolution activity than the TiO_(2) *** highest hydrogen-production efficiency of obtained CoS_(x)-rGO/TiO_(2)(10%) achieved 256.97 μmol·h-1,which was distinctly higher than that of TiO_(2)(4.41 μmol·h-1),rGO/TiO_(2)(20.19 μmol·h^(-1)) and CoS_(x)/TiO_(2)(132.67 μmol·h^(-1)).According to the results of various characterizations and tests,the synergistic-effect mechanism of CoS_(x) nanodots and rGO nanosheets is proposed to explain the increased photocatalytic performance of Co S_(x)-rGO/TiO_(2) photocatalytic material,namely the rGO nanosheets cause the quick transfer of photo-induced carriers from TiO_(2) to CoS_(x) nanodots,and then CoS_(x) nanodots work as hydrogenproduction active sites to quickly generate H_(2).The present study may offer innovative ideas for the preparation and application of new highly efficient and inexpensive photocatalytic materials.

关键词： Photocatalysis Hydrogen evolution Titania Cobalt sulphide Direct photodeposition

Optoelectronic characteristics and application of black phosphorus and its analogs

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Frontiers of physics 2021年第4期16卷 161-183页

作者： Ying-Ying Li Bo Gao Ying Han Bing-Kun Chen Jia-yu huo College of Communication Engineering Jilin UniversityChangchun 130012China

The tunable bandgap from 0.3 eV to 2 eV of black phosphorus(BP)makes it to fill the gap in *** studying the properties of BP more comprehensive,scientists have discovered that many twodimensional materials,such as tellurene,antimonene,bismuthene,indium selenide and tin sulfide,have similar structures and properties to black phosphorus thus called black phosphorus *** this review,we briefly introduce preparation methods of black phosphorus and its analogs,with emphasis on the method of mechanical exfoliation(ME),liquid phase exfoliation(LPE)and chemical vapor deposition(CVD).And their characterization and properties according to their classification of singleelement materials and multi-element materials are *** focus on the performance of passively mode-locked fiber lasers using BP and its analogs as saturable absorbers(SA)and demonstrated this part through classification of working ***,we introduce the application of BP and its analogs,and discuss their future research prospects.

关键词： black phosphorus and its analogs passively mode-locked fiber lasers optoelectronic characteristics saturable absorber

Study on the chaotic dynamics of the mode-locked fiber ring laser

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The Journal of China Universities of Posts and Telecommunications 2013年第3期20卷 104-108页

作者： GAO Bo WU Ge DUAN Tao huo Jia-yu TIAN Xiao-jian College of Communication Engineering Jilin University College of Electronic Science and Engineering Jilin University The Northern Institute of Electronic Equipment of China

In this paper, we study the chaotic dynamics of the mode-locked fiber laser by numerical simulation. The structures of the passively mode-locked fiber laser and the actively mode-locked fiber laser are studied by modeling and analysis. By appropriately adjusting the small signal gain of the optical fiber amplifier, we observe the period-doubling bifurcations and route to chaos in the passively mode-locked fiber laser based on nonlinear polarization rotation effect. Chaos in the actively mode-locked erbium-doped fiber laser is obtained by adjusting the elliptic modulus parameter of the active modulator and the intra-cavity length. Simulation results have theoretical significance for the practical application of chaotic soliton communication.

关键词： mode-locked fiber laser period-doubling chaos optical soliton

Diode-Pumped Nanosecond Pulsed Laser with Pulse-Transmission-Mode Q-Switch

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Chinese Physics Letters 2001年第2期18卷 228-229页

作者： CHEN Fei huo yu-Jing HE Shu-Fang FENG Li-Chun Department of Electronic Engineering Tsinghua UniversityBeijing 100084

Q-switched pulses at 1.064μm with a peak power of 5.02 kW and a pulse width of 2.8 ns were obtained which were pumped by a 1 W laser diode on the Nd:YVO4 microchip at the 1 kHz repetition *** values were achieved by combining the techniques of acousto-optic Q-switching and electro-optic pulse-transmission-mode *** temporal characteristics of the pulses were analysed *** experimental results are shown to be in good agreement with theoretical predictions.

关键词： pumped switched pulse

Allicin as add-on therapy for Helicobacter pylori infection: A systematic review and meta-analysis

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World Journal of Gastroenterology 2019年第39期25卷 6025-6040页

作者： Xiao-Bei Si Xu-Min Zhang Shuai Wang yu Lan Shuo Zhang Lin-yu huo Department of Gastroenterology Beijing Jishuitan HospitalBeijing 100035China Department of Cardiology Fu Wai HospitalNational Center for Cardiovascular DiseasesChinese Academy of Medical SciencesBeijing 100037China Department of Neurology Beijing Haidian HospitalBeijing 100080China

BACKGROUND Allicin(2-propene-1-sulfinothioic acid S-2-propenyl ester,diallyl thiosulfinate)extracted from garlic,has proven activity against Helicobacter pylori(***)*** recent years,clinical trials have explored its utility as an add-on therapy with variable outcomes *** To perform a systemic review of allicin as an add-on treatment for *** infection and assess its efficacy in randomized controlled trials(RCTs).METHODS Electronic databases including MEDLINE,EMBASE,the Web of Science,the Cochrane Database,the China National Knowledge Infrastructure Database,Chinese VIP Information Databases,Chinese Medical Databases,and the Wan-Fang Database were searched for keywords including“allicin”,“Helicobacter pylori”,“randomized clinical trials”,and their synonyms.A meta-analysis was performed using the fixed-effects model for low heterogeneity and the randomeffects model for high heterogeneity with sensitivity *** was evaluated using Egger’s *** sequential analysis(TSA)was used to evaluate information size and treatment *** Grading of Recommendations Assessment,Development and Evaluation(GRADE)was used to assess the level of quality,and studies were classed as“high quality”,“moderate quality”,“low quality”,and“very low quality”.RESULTS A total of eight RCTs consisting of 867 participants(435 from the allicin group and 432 from the control group)were *** rate in the allicin group(93.33%,406/435)was significantly higher than that of the control group(83.56%,361/432)[I2=0%,odds ratio(OR)=2.75,95%confidence interval(CI):1.74-4.35,P<0.001].The healing rate of ulcers following *** therapy in the allicin group(86.17%,349/405)was significantly higher than that of the control group(75.87%,305/402)[I2=0%,OR=2.05,95%CI:1.39-3.03,P<0.001].The total remission rate of peptic ulcers across all allicin groups was 95.99%,which was significantly higher than that of controls[95.99%(359/374)vs 89.25%(332/372),I2=0,hete

关键词： Allicin Helicobacter pylori Randomized controlled trials Add-on therapy Systematic review Meta-analysis