Recovery of zinc and iron from high iron-bearing zinc calcine by selective reduction roasting

Junwei Han,Wei Liu,Wenqing Qin,Bing Peng,Kang Yang,Yongxing Zheng 한국공업화학회 2015 Journal of Industrial and Engineering Chemistry Vol.22 No.-

A novel method to recover zinc and iron from high iron-bearing zinc calcine by reduction roasting-lowacid leaching-magnetic separation was proposed. The effects of roasting and leaching conditions wereinvestigated and their optimum conditions were established. Meanwhile, the mineralogical changesduring the processes were characterized by XRD, VSM, SEM and LPSA. The results show the ZnFe2O4 inthe calcine was decomposed into ZnO and Fe3O4, and about 92.6% Zn was extracted from the roastedcalcine with reporting most of iron as magnetite into the residue. Finally, more than 90% Fe wasrecovered from the residue by magnetic separation method.

Label-free Microarray-based Binding Affinity Constant Measurement with Modified Fluidic Arrangement

junwei Hu,Ru Chen,Chenggang Zhu,Bilin Ge,Xiangdong Zhu,Lan Mi,Jiong Ma,Caiqin Han,Hao Chen,Yiyan Fei 한국바이오칩학회 2018 BioChip Journal Vol.12 No.1

The oblique-incidence reflectivity difference (OI-RD) scanning microscopy has the capability of simultaneously measuring binding curves of a protein probe with tens of thousands molecular targets in a microarray and yielding reaction rate constants. However, the quality of reaction rate constants is influenced by the fluidic system. To improve the quality of reaction rate constant measurement over the entire microarray, we demonstrate a fluidic chamber that allows the fluid to flow from the bottom to the top uniformly across the microarray and thus provides more uniform and accurate measurements of reaction rate constants with simplified fluidic design.

Dynamical Analysis of Memcapacitor Chaotic System and Its Image Encryption Application

Junwei Sun,Gaoyong Han,Yanfeng Wang 제어·로봇·시스템학회 2020 International Journal of Control, Automation, and Vol.18 No.5

The prospective studies on memcapacitor models and potential applications are of importance due to its dynamical behavior. For this purpose, a memcapacitor model and a corresponding circuit model have been designed, whose characteristics have been investigated theoretically and experimentally. Based on the unique space conformation of DNA molecules and their unique information storage and processing ability, a memcapacitor chaotic image encryption algorithm combining with DNA sequence operations is proposed in the first time. DNA sequence operations and memcapacitor chaos iterations are used in the encryption process to strengthen the confusion and diffusion properties of the scheme. The simulation results and theoretical analysis show that the algorithm improves the sensitivity of key and the security of data transmission, and has better ability of the hacker attacks.

Influence of post-pouring joint on long-term performance of steel-concrete composite beam

Dunwen Huang,Junwei Han,Xiaochun Liu,Shizhuo Zhang,Tao Chen 국제구조공학회 2018 Steel and Composite Structures, An International J Vol.28 No.1

The concrete bridge decks are usually precast and in-situ assembled with steel girders with post-pouring joint in the construction practice of super-wide steel-concrete composite beam. But the difference of concrete age between the precast slabs and the post-pouring joint has been not yet considered for the long-term performance analysis of this kind composite beam. A simply supported precast-assembled T-shaped beam was taken as an example to analyze the long-term performance of steel-concrete composite beam with post-pouring joint. Based on the deformation coordination conditions of the old-new concrete deck and steel girder, a theoretical model for the long-term behavior of precast-assembled composite beam is proposed in this paper according to age-adjusted effective modulus method. Then, the feasibility of the proposed model is verified by the available test data from the Gilbert's composite beams. Parametric studies were preformed to evaluate the influences of the cross-sectional area ratio of the post-pouring joint to the whole bridge deck, as well as the difference of concrete age between the precast slabs and the post-pouring joint, on the long-term performance of the composite beam. The results indicate that the traditional method without considering the age difference would seriously underestimate the effect of creep and shrinkage of concrete bridge decks. The concrete age difference between the precast slabs and the post-pouring joint should be demonstrated for the life cycle design and long-term performance analysis of precast-assembled steel-concrete composite beams.

Metal Adsorbate-Induced Plasmon Damping in Gold Nanorods: The Difference Between Metals

Pengyu Xu,Xuxing Lu,Junwei Zhao,Yue Li,Sheng Chen,Junfei Xue,Weihui Ou,Song Han,YAPING DING,Weihai Ni 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2016 NANO Vol.11 No.9

We presented a single particle study on the metal adsorbate-induced plasmon damping in Au nanorods (AuNRs) through adsorbing clusters of different metals including Pt, Au and Ag. AuNRs with different longitudinal surface plasmon resonance (LSPR) wavelength were measured and investigated individually. Linewidth broadening, plasmon shift and reduction of plasmonic resonance of single AuNRs were studied and compared between Pt, Au and Ag adsorbates. The measured linewidths perfectly match the theoretical predictions of the billiard model with increased scattering coefficients resulted from the metal adsorbates. The results indicate that the plasmon damping in case of Ag is significantly weaker than Pt and Au, which can be attributed to longer relaxation time of free electrons in Ag and therefore less loss of the oscillating plasmon electrons. In contrast to the red shift observed from Au and Pt, blue shift of the LSPR is observed in case of Ag. It suggests that plasmonic properties brought by the metal adsorbates can exert dramatic influence on the nanoparticle that is adsorbed with. We believe that our study not only provides important understanding on plasmon damping but pave the road for the fabrication of complex nanostructures with two or more metal elements.

Application and Research of Monte Carlo Sampling Algorithm in Music Generation

Jun MIN,Lei WANG,Junwei PANG,Huihui HAN,Dongyang Li,Maoqing ZHANG,Yantai HUANG 한국인터넷정보학회 2022 KSII Transactions on Internet and Information Syst Vol.16 No.10

Composing music is an inspired yet challenging task, in that the process involves many considerations such as assigning pitches, determining rhythm, and arranging accompaniment. Algorithmic composition aims to develop algorithms for music composition. Recently, algorithmic composition using artificial intelligence technologies received considerable attention. In particular, computational intelligence is widely used and achieves promising results in the creation of music. This paper attempts to provide a survey on the music generation based on the Monte Carlo (MC) algorithm. First, transform the MIDI music format files to digital data. Among these data, use the logistic fitting method to fit the time series, obtain the time distribution regular pattern. Except for time series, the converted data also includes duration, pitch, and velocity. Second, using MC simulation to deal with them summed up their distribution law respectively. The two main control parameters are the value of discrete sampling and standard deviation. Processing the above parameters and converting the data to MIDI file, then compared with the output generated by LSTM neural network, evaluate the music comprehensively.

Prediction of exploration targets based on integrated analyses of source rock and simulated hydrocarbon migration direction: a case study from the gentle slope of Shulu Sag, Bohai Bay Basin, northern China

Changqing Ren,Fugui He,Xianzhi Gao,Dongsheng Wu,Wenli Yao,Jianzhang Tian,Huiping Guo,Yuanxin Huang,Li Wang,Han Feng,Junwei Li 한국지질과학협의회 2019 Geosciences Journal Vol.23 No.6

The Shulu Sag which is a rifted sag with NNE trend is located in the south of Jizhong Depression, Bohai Bay Basin, northern China. The gentle slope and three troughs are situated in the west and east of the sag, respectively. Both of the lower part of Shasan Member (Es3x) and the lower part of Shayi Member (Es1x) act as source rocks in this sag. Researches on the type, quantity, quality and thermal maturity of the respective organic matter have been conducted using Rock-Eval pyrolysis data. Type II is the dominant kerogen in Es1x of all troughs. However, Type II1 and III is the dominant kerogen in Es3x of Middle-Southern and Northern trough, respectively. TOC (total organic carbon) and pyrolysis S2 (hydrocarbon) values suggest that the Es1x source rocks in Middle-Southern and Northern trough are fair to good and poor to fair generative potential of hydrocarbon, separately. The Es3x source rocks in Middle-Southern and Northern trough possess fair to excellent and poor to fair generative potential of hydrocarbon, individually. Tmax (pyrolysis temperature at maximum S2) values indicate that most of Es3x samples are thermally mature, but all Es1x samples are thermally immature. Under large scale condition, the hydrocarbon secondary migration in the upper part of Shasan Member (Es3s), Shaer Member (Es2) and the upper part of Shayi Member (Es1s) have been simulated using fluid potential model with Arcgis 9.3 software. The simulation results reveal the direction of hydrocarbon secondary migration and the distribution of hydrocarbon migration-accumulation units (HMAUS), and also suggest that the hydrocarbon migration direction is obviously controlled by nose-like structure belts where most of hydrocarbons accumulate. That shows high reliability because they are consistent with the hydrocarbon exploration result in this area. On the basis of integrated analyses of source rocks and hydrocarbon migration direction, the following five areas in the gentle slope are identified to be the preferred hydrocarbon accumulation area: Taijiazhuang area, northern and southern Xicaogu area, as well as northern and southern Leijiazhuang area. It is considerably helpful to reduce the risk in hydrocarbon exploration of Shulu Sag.