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1

Extraction of rubidium and cesium from brine solutions using a room temperature ionic liquid system containing 18-crown-6

Huang D., Zheng H., Liu Z., Bao A., Li B.

Polish Journal of Chemical Technology

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2018

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Vol. 20, nr 2

40--46

EN

Application of 1-butyl-3-metyhlimidazaolium hexafl uorophosphate ([C4mim][PF6 ]), in the extraction of rubidium and cesium from brine solutions using 1,4,7,10,13,16-hexaoxacyclooctadecane (18C6) as extractant was investigated. Parameters that affect the extraction including pH of aqueous phase, equilibration time, dosage of the ionic liquid, phase ratio, concentration of 18C6 were studied. Under the optimal conditions, the single extraction effi ciency of rubidium ions and cesium ions were up 84.11% and 94.99%, respectively. The stripping of alkali metal ions from the loaded organic phase with different stripping agents and concentrations were also investigated. The initial value of the K/Cs and K/Rb ratios were 93.0 and 104.3, respectively, which have dropped 91.21% and 88.01%, respectively, after the extraction and stripping experiments. It was taken a big step in the separation and enrichment of cesium (rubidium) ion and potassium ion. The extraction mechanism was revealed most likely to be a cation exchange mode in this system.

2

Improving spodumene flotation using a mixed cationic and anionic collector

Wang Y., Zhu G., Yu F., Lu D., Wang L., Zhao Y., Zheng H.

Physicochemical Problems of Mineral Processing

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2018

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Vol. 54, iss. 2

567--577

EN

Lithium, a rare-earth element, has been in increasing demand. Spodumene flotation is an important and challenging step for lithium extraction and production from lithium ore. In the present work, flotation tests for three pure minerals (i.e., spodumene, quartz and feldspar) and a real spodumene ore were carried out at laboratory scale. The results showed that YOA, a mixture of oleic acid and dodecylamine with the molar ration of 10:1, could be used as collector to produce a spodumene concentrate with grade of 5.59% Li2O from the feed ore with grade of 1.48% Li2O where 85.24% of Li2O was recovered to the concentrate. The measured zeta potential, contact angle and adsorption capacity indicated that YOA was preferentially adsorbed on spodumene instead of on quartz or feldspar, with the spodumene surface being more hydrophobic than that of feldspar or quartz. The adsorption energies of YOA on spodumene were calculated and the results provided insights into the superior flotation performance obtained in the present work.

3

Experimental seismic performance of steel- and composite steel-panel wall strengthened steel frames

Jiang L., Zheng H., Hu Y.

Archives of Civil and Mechanical Engineering

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2017

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Vol. 17, no. 3

520--534

EN

This paper presents an experimental study to investigate the seismic performance of steel- and composite steel-panel wall strengthened steel frames (SPWF and CPWF). A detailed experimental investigation of five 1/3-scaled specimens with one-bay and single-story was conducted. The failure modes, load-carrying capacity, hysteretic behavior, ductility, energy dissipation capacity were presented and analyzed. The effects of the length-to-height ratio, stiffeners, and the type of walls on the seismic behavior were also investigated. The experimental results show that the specimens tolerate 4% to approximately 5% story drift, the steel- and composite steel-panel wall improved the seismic performance of the steel frame. The length-to-height ratio has had large effect on load-carrying capacity, initial stiffness, ductility and response modification factor. In addition, finite element (FE) models of SPWFs and CPWFs were established to simulate their nonlinear behavior, and the results were verified by the experimental results. The failure mode obtained from the numerical simulation was in accordance with the experimental phenomenon. Furthermore, formulas were developed to estimate initial lateral stiffness and shear strength of the test specimens, and such theoretical predictions were verified by the experimental results.

4

A Hybrid Invasive Weed Optimization with Feasibility-Based Rule for Constrained Optimization Problem

Chen H., Zhou P., Guo P., Ouyang X., He S., Zheng H.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 4

160-167

EN

During the past decade, hybrid algorithms combining evolutionary computation and constraint-handling techniques is one of the most popular method to solve constrained optimization problems. Usually, penalty functions are often used in constrained optimization. But it is difficult to strike the right balance between objective and penalty functions. As a novel population-based algorithm, invasive weed optimization (IWO) algorithm has gained wide applications in a variety of fields, especially for unconstrained optimization problems. In this paper, a hybrid IWO (HIWO) with a feasibility-based rule is proposed to solve constrained optimization problems. The feasibility-based rule does not need additional parameters, which is different from penalty functions. In addition, the complex method is used to provide direction for weed evolution, which can accelerate the convergence speed. Simulation and comparisons based on several well-studied benchmarks demonstrate the effectiveness, efficiency and robustness of the proposed HIWO.

PL

W artykule przedstawiono opracowaną metodę optymalizacji z funkcją kosztu, bazującą na hybrydowej metodzie IWO (ang. Hybrid Invasive Weed Optimizastion) oraz regułach związanych z wykonalnością. Zasady wykonalności, w przeciwieństwie do funkcji kar, nie wymagają dodatkowych parametrów. Dodatkowo zastosowano kompleksową metodę określania kierunki ewolucji trawy w algorytmie IWO, co pozwala na przyspieszenie konwergencji. Przeprowadzone badania symulacyjne i porównawcze dowodzą skuteczności i sprawności proponowanej metody HIWO.

5

A Condition Assessment Model of Oil-immersed Transformers Using Cloud and Matter Element Integrated Method

Liao R., Zhang Y., Zheng H., Yang L., Wang K., Akram S.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 4

142-146

EN

High voltage oil-immersed transformers are the most important components in the power system. If there is a potential fault in the transformer it may cause a power failure even a catastrophe. Therefore, it is important to assess the condition of the transformer accurately and to make some relative maintenance to minimize the risk of premature failure. However, condition assessment of transformers can be considered as a multiple-attribute decision-making (MADM) problem which is full of uncertain, fuzzy and randomness information. Aiming at this intricate problem, this paper presents a cloud and matter element integrated approach for assessing the condition of transformers. An assessing index system is established, which includes dissolved gas analysis (DGA), electrical testing and oil testing. An integrated model based on matter element approach and cloud approach is applied to assess the condition of the transformer. Cases study show that the proposed approach is practical and effective. The assessing result can be regarded as a useful suggestion to condition based maintenance of high voltage oil-immersed transformers.

PL

W artykule przedstawiono metodę oceny stanu technicznego transformatora olejowego, opartą na analizie elementów chmury oraz tzw. Matter-Element Analysis. Opracowany został zintegrowany model oraz wskaźnik szacujący stan transformatora, uwzględniający czynniki takie jak: analiza rozpuszczonych gazów (DGA), testy elektryczne i olejowe. Przeprowadzone badania potwierdziły skuteczność metody.

6

Analiza dostępności konstelacji satelitów

Zheng H., Ren L.

Eksploatacja i Niezawodność

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2010

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nr 2

48-50

EN

This paper firstly analyzes the concept of availability of satellite constellation. Then the method of constellation availability analysis is proposed based on Markov chain model, outage analysis, as well as MTBF and MTTR of satellite constellations. Finally, an illustrative example is presented to demonstrate the method.

PL

Artykuł w pierwszej kolejności analizuje pojęcie dostępności konstelacji satelitów. Następnie proponuje metodę analizy dostępności konstelacji opartą na modelu łańcuchów Markowa, analizie przestojów, oraz MTBF i MTTR konstelacji satelitów. Metodę zilustrowano przykładem.

7

Tetrahydroxyflavanol-modified TiO2 nanoparticles for solid phase extraction of trace Al(III) and Cr(III) from food and natural water samples

Zheng H., Ma S.

Chemia Analityczna

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2009

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Vol. 54, No. 6

1309-1320

EN

In this work, a novel method using a microcolumn packed with tetrahydroxyflavanol-modi-fied TiO, nanoparticles lor simultaneous preconcentration of trace AI(III) and Cr(IlI) prior to their ICP-OHS determination has been developed. Separation/preconcentration conditions, including pll, sample flow rate and volume, as well as elution conditions and the effect of interfering ions on the recovery of the analytes were investigated. At pH 4, absorption capacity of tetrahydroxyflavanol-modified nano-TiO, was 6.75 mg g-1 and 9.69 mg g-1for AI(III) and Cr(III). respectively. Detection limits (3o) of Al(III) and Cr(III) were 0.49 and 0.21 ng mL-1, respectively. The method was successfully applied to the determination of trace Al(III) and Cr(lII) ions in food and water samples with satisfactory results.

PL

Opracowano nową metodę zatężania śladowych ilości Al(III) i Cr(III) przed oznaczaniem techniką ICP OILS z użyciem mikrokolumny wypełnionej nanocząstkami TiO2 modyfikowanymi tetrahydraksyflawanolem. Zoptymalizowano warunki prowadzenia procesu: pH, szybkość przepływu roztworu próbki, warunki wymywania analitów, a także przeszkadzający wpływ wybranych jonów na ich odzysk. Stwierdzono, że przy pH 4 pojemność sorpcyjna zastosowanego złoża wynosiła 6,75 i 9,69 mg g-1 odpowiednio dla AI(III) i Cr(III). Granice wykrywalności Al(lll) i Cr(III) wynosiły odpowiednio 0,49 i 0,21 ng g-1. Metodę z powodzeniem zastosowano do oznaczania śladowych ilości Al(IlI) i Cr(III) w wodach i produktach żywnościowych.

8

Selective solid-phase extraction of Hg(II) using silica gel surface : imprinting technique

Zheng H., Geng T., Hu L.

Chemia Analityczna

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2008

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Vol. 53, No. 5

673-687

EN

A new ion-imprinted amino-functionalized silica gel sorbent was synthesized by surface-imprinting technique for preconcentration and separation of Hg(II) prior to its determination by inductively coupled plasma optical emission spectrometry (ICP—OES). Compared to the traditional solid sorbents and non-imprinted polymer particles, the ion-imprinted polymers (IlPs) have higher adsorption capacity and selectivity for Hg(II). The maximum static adsorption capacity of the imprinted and non-imprinted sorbent for Hg(II) was 29.89 mg g-1 and 11.21 mg g-1, respectively. The highest selectivity coefficient for Hg(II) in the presence of Zn(II) exceeded 230. The detection limit (3a) of the method was 0.25 μg L-1. The relative standard deviation of the method was 2.5% for eight replicate determinations of 10 ug of Hg2+ in 200 mL-in-volume water sample. The procedure was validated byperforming the analysis of the certified river sediment sample (GBW 08603, China) using the standard addition method. The developed method was also successfully applied to the determination of trace mercury in Chinese traditional medicine and water samples with satisfactory results.

PL

Stosując technikę modyfikowania powierzchni grupami aminowymi otrzymano nowy, jonowo dopasowany żel krzemionkowy służący do zatężania i oddzielania Hg(II) przed jej oznaczeniem za pomocą optycznej spektrometrii emisyjnej ze wzbudzeniem w plazmie indukcyjnie sprzężonej (1CP—OES). W porównaniu z tradycyjnymi, stałymi sorbentami i niemodyfikowanymi polimerami, polimery dopasowane jonowo (ion-imprinted polymers - IIPs) mają większą pojemność adsorpcyjną oraz selektywność względem Hg(II). Maksymalna statyczna pojemność adsorpcyjną Hg(Il) w przypadku sorbentu modyfikowanego i niemodyfikowanego wynosiła odpowiednio 29,89 mg gg-1i 11,21 mg gg-1. Najwyższy współczynnik selekty wności Hg(lł) względem Zn(II) przekraczał 230. Granica wykrywalności (3a) wynosiła 0.25 μg L-1. Względne odchylenie standardowe, obliczone z 8 oznaczeń próbki wody zawierającej w 200 mL lO μg HgHg2+, wynosiło 2,5%. Metodę zwalidowano wykonując analizę certyfikowanych próbek osadów rzecznych (GBW 08603, Chiny) metodą dodatku wzorca. Opracowaną metodę z powodzeniem zastosowano do oznaczania śladów rtęci w tradycyjnej chińskiej medycynie oraz w próbkach wody.

9

Numerical analysis of one-dimensional nonlinear acoustic wave

Zheng H., Morozov I.B., Zhang Z.

Acta Geophysica

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2007

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Vol. 55, no. 3

313-323

EN

Numerical investigations on one-dimensional nonlinear acoustic wave with third and fourth order nonlinearities are presented using high-order finite-difference (HFD) operators with a simple flux-limiter (SFL) algorithm. As shown by our nu-merical tests, the HFDSFL method is able to produce more stable, accurate and conservative solutions to the nonlinear acoustic waves than those computed by finite-difference combined with the flux-corrected-transport algorithm. Unlike the linear acoustic waves, the nonlinear acoustic waves have variable phase velocity and waveform both in time-space (t-x) domain and frequency-wavenumber (f-k) domain; of our special interest is the behaviour during the propagation of nonlinear acoustic waves: the waveforms are strongly linked to the type of medium nonlinearities, generation of harmonics, frequency and wavenumber peak shifts. In seismic sense, these characteristics of nonlinear wave will introduce new issues during such seismic processing as Normal Moveout and f-k filter. Moreover, as shown by our numerical experiment for a four-layer model, the nonlinearities of media will introduce extra velocity errors in seismic velocity inversion.

10

Preconcentration and separation of Zn2+ using surface zinc(II) imprinted functionalized silica gel sorbent

He Q., Chang X., Zheng H., Jiang N., Hu Z., Zhai Y.

Chemia Analityczna

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2006

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Vol. 51, No. 5

715-725

EN

Zinc(II) imprinted amino-functionalized silica gel sorbent was synthesized applying surface-imprinting technique in order to preconcentrate and separate Zn2+ prior to its determination by inductively coupled plasma optical emission speclrometry (1CP-OES). Compared to traditional solid sorbents and non-imprinted sorbent, zinc(U)-irnprinted sorbent has higher selectivity and adsorption capacity towards Zn2+. Maximum static adsorption capa cities of ion-imprinted and non-imprinted sorbent towards Zn2+ were 12.98 mg g-1 and 4.36 mg g -1, respectively. The largest separation factor for zinc(II) imprinted sorbent towards Zn+2 in the presence of Hg+2 was higher than 188. Relative selectivity coefficient (&alfa;r) values for Zn+2 Hg+2 pair were 15.5 and 13.8-both greater than 1. Distribution coefficient (D) valuesofzinc(II) imprinted polymers to wards Zn2+ were greatly larger than those for Hg+2 . Detection limit (3 σ) of the method was 0.29 μg L-1 and relative standard deviation equalled 2.6% for eight replicate determination of 10 μg of Zn+2 in 200 mL-in-volume water sample. The proposed method was applied to the determination of trace zinc in biological and water samples with satisfactory results.

PL

Zsynletyzowano sorbent krzemionkowy do którego wprowadzono grupy aminowe z dopasowanym molekularnie Zn(II) stosując technikę dopasowania powierzchniowego. Sorbent . został zastosowany do wstępnego zatężenia i oddzielania Zn2+ przed jego oznaczaniem za pomocą spektometrii emisyjnej z plazmą sprzężoną indukcyjnie (ICP-OES). W porównaniu do tradycyjnych sorbentów oraz tego samego sorbentu „bez dopasowania molekularnego'', sorbent „z dopasowaniem molekularnym względem Zn(tl)" wykazuje lepszą selektywność i wyższą zdolność sorpcyjną względem 72+. Maksymalne zdolności sorpcyjne względem cynku sorbentu „z dopasowaniem" i „bez dopasowania molekularnego" wynosiły odpowiednio: 12.98 mg g-1 oraz 4.36 mg g-1. Największy współczynnik rozdzielenia jonów Zn+2 i Hg+2 w przypadku jonitu „z dopasowaniem molekularnym względem Zn(II)'' przewyższał 188. Względny współczynnik selektywności określający na ile współczynnik rozdzielenia pary Zn+2/Hg+2 w przypadku sorbentu ,.z dopasowaniem względem Zn(II)" jest lepszy niż w przypadku sorbentu ,,bez dopasowania został wyznaczony jako 15.5 lub 13.8 a więc był znacznie większy niż 1. Współczynniki podziału (D) dla jonitu z dopasowaniem Zn(II)były znacznie wyższe dla Zn+2 niż dla Hg+2. Granica wykrywalności (3σ) metody wyniosła 0.29 μ.g L-1 a względne odchylenie standardowe obliczone z ośmiu kolejnych oznaczeń 10 μg Zn+2 w 200 mL próbce wody wynosiło 2.6%. Zaproponowaną metodę zastosowano z powodzeniem do oznaczania śladów cynku w materiałach biologicznych i próbkach wody.

11

Rapid detection of trace chloroethylenes sing laser mass spectrometry

Ma J., Ding L., Fang L., Zheng H., Gu X., Zhang W.

Optica Applicata

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2005

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Vol. 35, nr 2

395-402

EN

Laser mass spectrometry is a new chemical trace analysis method with high selectivity, sensitivity and speed. The mass-resolved resonance-enhanced multiphoton ionization (REMPI) spectra of chloroethylenes-trichloroethylene and tetrachloroethylene are firstly reported in the range 305.0-325.0 nm. The mass-resolved excited spectra and laser power index of fragment ions CCl+ are presented. The experimental results indicate that 310.8 nm is the suitable ionization wavelength for detection of trichloroethylene and 322.5 nm for the detection of tetrachloroethylene in this wavelength range. The detection limits of these two chloroethylenes of concentration range expressed in ug/L are presented.

12

New developments in Computer Based Training (CBT) interactive programs for marine engineering students and ship engineers

Cwilewicz R., Gałecki W., Tomczak L., Zheng H.

Polish Maritime Research

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1999

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nr 1

13-18

EN

This paper describes new developments in application of CBT interactive programs intended for familarization with indyvidual equipment devices such as boilers, fresh water generators, steering gear, anti-pollution plants, diesel electric generators etc. Experience gained in CBT applications, benefits and advantages of the use of interactive programs in the education process of ship's engineers are also presented.