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1

Experiment and prediction of water content of sour natural gas with an modified cubic plus association equation of state

Liu Y., Zhu Y., Zhu J.

Polish Journal of Chemical Technology

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2018

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Vol. 20, nr 2

98--106

EN

In this work, new experimental value for water content in sour natural gas were reported. In addition, to predict the water content in sour natural gas, a modified cubic plus association equation of state (CPA-EoS) was also proposed. In this model, a new energy parameter a was proposed to make an accurate description of saturated liquid density. Additionally, a temperature dependent binary interaction parameter kij for six binary systems was also obtained. Lastly, a comparison between the prediction results of the modified CPA-EoS and the experimental data was presented, and the results showed that the modifi ed CPA-EoS could predict the water content in sour natural gas with high accuracy, which has an AAD of 3.6722% with experimental data in literatures and an AAD of 1.946% for experimental data reported in this work.

2

Diethylenetriamine-assisted one-step hydrothermal synthesis of cotton-like CoS cluster for high-performance supercapacitor

Zhu J., Xiang L., Zhou Y., Yang J.

Materials Science Poland

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2018

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Vol. 36, No. 2

297--303

EN

Cotton-like CoS cluster has been successfully synthesized via a simple one-step hydrothermal route assisted by diethylenetriamine (DETA) as a ligand and structure-directing agent. The structure and morphology of the product were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM) and N2 adsorption-desorption isotherm. The CoS sample which has a hexagonal phase without any impurities possesses a microscopic morphology made by cotton-like clusters. The as-fabricated CoS as a supercapacitor electrode presents desirable supercapacitive performance with a high specific capacitance (664 F·g-1 at 0.5 A·g-1), remarkable rate capability and excellent cycling stability (85.7 % specific capacitance retention after 1000 cycles), making it applicable as an electrode for high-performance supercapacitors.

3

An ant-based filtering random-finite-set approach to simultaneous localization and mapping

Li D., Zhu J., Xu B., Lu M., Li M.

International Journal of Applied Mathematics and Computer Science

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2018

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Vol. 28, no. 3

505--519

EN

Inspired by ant foraging, as well as modeling of the feature map and measurements as random finite sets, a novel formulation in an ant colony framework is proposed to jointly estimate the map and the vehicle trajectory so as to solve a feature-based simultaneous localization and mapping (SLAM) problem. This so-called ant-PHD-SLAM algorithm allows decomposing the recursion for the joint map-trajectory posterior density into a jointly propagated posterior density of the vehicle trajectory and the posterior density of the feature map conditioned on the vehicle trajectory. More specifically, an ant-PHD filter is proposed to jointly estimate the number of map features and their locations, namely, using the powerful search ability and collective cooperation of ants to complete the PHD-SLAM filter time prediction and data update process. Meanwhile, a novel fast moving ant estimator (F-MAE) is utilized to estimate the maneuvering vehicle trajectory. Evaluation and comparison using several numerical examples show a performance improvement over recently reported approaches. Moreover, the experimental results based on the robot operation system (ROS) platform validate the consistency with the results obtained from numerical simulations.

4

Experimental study on bridge–track system temperature actions for Chinese high-speed railway

Lou P., Zhu J., Dai G., Yan B.

Archives of Civil and Mechanical Engineering

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2018

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Vol. 18, no. 2

451--464

EN

Atmospheric temperature and directed solar radiation have a significant effect on the temperature field of high-speed railway (HSR) concrete bridge and ballastless track structure. However, temperature actions are random process of which distribution laws are difficult to explore, and existing statistical methods for structure temperature analysis are still not precise. So far, there are few researches for annual temperature spectra and design codes for bridge–track system. Based on the one-year observation data, this paper investigated the temperature actions for Chinese HSR bridge–track structure. By utilizing reliability high moment theory, a statistical method which could built virtual distribution was put forward. Based on the renewed study, the effects of waterproof for deck were taken into consideration, a temperature action model was proposed which is suitable for both bridge and track structure. In addition, for track structure, the previous temperature load models were modified. Apart from that, by proposing the concepts of temperature uniform and fluctuant spectra, the research evaluated service performance of structure. Finally, the distribution regularities of uniform temperature spectra were fitted by Fourier series, and the relationship between structural and atmospheric uniform temperature was established (formula (25)). As a result, according to 50 years recorded atmospheric temperature data, the prediction model of the structure extreme temperature was suggested, and by taking the recurrence interval of 100, 150 and 300 years, the extreme temperatures of the system are 52.23, 54.34 and 57.77 °C.

5

Preparation of micro-encapsulated strawberry fragrance and its application in the aromatic wallpaper

Xiao Z., Zhang Y., Zhu G., Niu Y., Xue Z., Zhu J.

Polish Journal of Chemical Technology

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2017

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Vol. 19, nr 1

89--94

EN

Micro-encapsulated strawberry fragrance was successfully prepared with wall materials including maltodextrin, sodium octenylsuccinate and gum Arabic. The micro-capsule was added to wallpaper and aromatic wallpaper with strawberry characteristics was obtained. The particle distribution, surface morphology, chemical structure, thermal property and controlled release performance of micro-encapsulated fragrance and aromatic wallpaper were investigated using laser particle size analyzer, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT-TR), thermal gravity analysis (TGA) and chromatography-mass spectrometer (GC-MS). The results showed that the average diameter of micro-capsule was 2 μm and the particles mainly distributed in the tissues of wallpaper. The result of TGA showed that the micro-capsule had a good stability. Meanwhile, the aromatic wallpaper had strawberry aroma more than 3 months and took on excellent controlled release performance.

6

Double-layer microwave absorber based on nanocrystalline CoFe2O4 and CoFe2O4/PANI multi-core/shell composites

Xu Y., Shen G., Wu H., Liu B., Fang X., Zhang D., Zhu J.

Materials Science Poland

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2017

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Vol. 35, No. 1

94--104

EN

Organic-inorganic nano-CoFe2O4/PANI (polyaniline) multi-core/shell composites have been successfully synthesized by chemical oxidative polymerization of aniline. The characterization results showed that the ferrite nanocrystals were efficiently embedded in PANI. The electromagnetic parameters of the composites were measured by a vector network analyser in the frequency range of 2 GHz to 18 GHz. Double-layer absorbers based on the CoFe2O4/PANI composite (matching layer) and calcined CoFe2O4 ferrite (absorbing layer) have been designed. The reflection loss of the microwave absorbers of both single layer and double-layer with a total thickness of 2.0 mm and 2.5 mm was calculated according to transmission-line theory. The results indicated that the minimum reflection loss of the CoFe2O4/PANI composite was −19.0 dB at 16.2 GHz at the thickness of 2.0 mm and −23.6 dB at 13.1 GHz at the thickness of 2.5 mm, respectively. The minimum reflection loss for double-layer absorbers reached −28.8 dB at 16.2 GHz at the total thickness of 2.0 mm, and −31.1 dB at 12.8 GHz at the total thickness of 2.5 mm. The absorption bandwidth under −10 dB was 4.2 GHz (13.8 GHz to 18.0 GHz) and 5.5 GHz (10.3 GHz to 15.8 GHz), respectively. The results show that the reflection loss and absorption bandwidth of the double-layer absorbers are obviously enhanced compared to corresponding single layer absorbers.

7

Simultaneous removal of NH4+ and PO43- from simulated reclaimed waters by modified natural zeolite. Preparation, characterization and thermodynamics

Alshameri A., He H., Dawood A. S., Zhu J.

Environment Protection Engineering

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2017

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Vol. 43, nr 4

73--92

EN

Natural zeolite was modified by NaCl, AlCl3 and thermal treatment for the removal of NH4+ and PO43− ions. The characteristics of the modified zeolite (AlZ) and its mechanism for the NH4 + and PO43− removal were studied and compared. The results showed that the surface area and the Na+ and Al3+ content increased whereas the content of Ca2+, K+ and Mg2+ decreased after zeolite modification. On natural zeolite when activated with the 1 M NaCl and 10 cm3 /g of pillaring dosage, high adsorption efficiencies for the NH4 + (97.80%) PO43− (98.60%) were obtained. The results of various analyses indicated that the Na+ exchange is the main mechanism for NH4 + removal whereas the adsorption mechanism for PO43− followed the complexation with Al–OH groups present in the AlZ. In addition, the kinetics study showed that the adsorption of NH4+ and PO43− followed pseudo-second order model while the adsorption isotherm of NH4 + and PO43− is consistent with the Langmuir isotherm model. Moreover, the Gibbs free energy change for the simultaneous removal of the ions indicates that NH4 + is adsorbed faster compared to PO43−. The simultaneous removal of NH4 + and PO43− by AlZ adsorbent is cost effective in water treatment at low ion concentrations.

8

A new simulation-optimization approach for the circulation facilities design at urban rail transit station

Khattak A., Jiang Y., Zhu J., Hu L.

Archives of Transport

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2017

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Vol. 43, iss. 3

69--90

EN

Width design of the urban rail transit stations circulation facilities is a vital issue. The existing width design approach failed in fully considering the essential factors such as fluctuation in passengers’ arrival process, fluctuation and state-dependence in passengers walking speed and the blocking when passengers’ demand exceeds the capacity of facilities. For this purpose, a PH-based simulation-optimization approach is proposed that fully considers the fluctuation, the state-dependence, Level of Service (LOS) and blocking effect. This novel approach provides automatic reconfiguration of the widths of circulation facilities by a concurrent implementation of a PH-based Discrete-Event Simulation (DES) model and the Genetic Algorithm (GA). The proposed PH-based simulation-optimization approach and the existing design approaches based on the exponential and deterministic models are applied to design the widths of circulation facilities. The results reveal that the circulation facilities designed by the proposed approach have larger widths. Similarly, increase in the SCV of arrival interval results in increasing the widths designed by the proposed approach increase while the widths of the other two approaches stay the same. The width designed of the proposed approach increase at faster rate than that of the other two approach when the passengers’ arrival rate increases.

9

Comprehensive characterization and quantification of phillyrin in the fruits of Forsythia suspensa and its medicinal preparations by liquid chromatography-ion trap mass spectrometry

Chen J., Chen Q., Yu F., Huang H., Li P., Zhu J., He X.

Acta Chromatographica

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2016

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Vol. 28, no. 1

145--157

EN

A rapid and sensitive method for the identification and quantification of phillyrin (POG) in Forsythia suspense is described. The phillyrin standard solution was directly infused into the ion trap mass spectrometers (IT-MS) for collecting the MSn spectra. The electrospray ionization (ESI) mass spectral fragmentation pathway of phillyrin was proposed, and the ESI-MSn fragmentation behavior of phillyrin was deduced in detail. The major product ion at m/z 355 belongs to furofuran, which was formed by loss the glucopyranoside (180 Da), and the characteristic fragment ions m/z 473, 395, 337, 309, and 249 were observed. The loss of 18 Da could arise from two different fragmentation pathways, and the observed ion was composed of a mixture of two different structural ions. Quantification of phillyrin was assigned in positive-ion mode at a product ion at m/z 557 → 355 by liquid chromatography-mass spectrometry (LC-MS). The LC-MS method was validated for linearity, sensitivity, accuracy, and precision and then used to determine the content of the phillyrin. Lastly, the LC-MS method was successfully applied to determine phillyrin in real sample F. suspense and three of its medicinal preparations in the positive mode at the first time.

10

Graphene synthesis: a Review

Shams S. S., Zhang R., Zhu J.

Materials Science Poland

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2015

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Vol. 33, No. 3

566--578

EN

Graphene has achieved a great amount of popularity and interest from the science world because of its extraordinary physical, mechanical and thermal properties. Graphene is an allotrope of carbon, having one-atom-thick planar sheets of sp2 bonded carbon atoms densely packed in a honeycomb crystal lattice. Many methods to synthesize graphene have been developed over a short period and we believe it is necessary to create a list of the most notable approaches. This article focuses on the methods to synthesize graphene in an attempt to summarize and document advancements in the synthesis of graphene research and future prospects.

11

The Theoretical Analysis Model and Statistical Test Research on Enterprises Development - A Study of Data from 195 Large and Medium Manufacturing Enterprises in China

Yin H., Guo T., Li B., Zhu J., Sun X.

Przegląd Elektrotechniczny

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2013

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R. 89, nr 3b

198--206

EN

On the basis of dynamic capabilities theory, this paper has put forward the theoretical analysis model and examined questionnaire data from 195 large and medium manufacturing enterprises in 2011 through statistical test methods including intermediary role term and SEM model. The results are as follows: first, in the test for basic constructs, the correlation of independent and dependent variables Sig. <0.001 and Pearson coefficient>0.500, all multiple correlation coefficient > 0.800, all determination coefficient R2 >0.650, Durbin-Watson coefficient approximated to 2.000, all check coefficient has presented distinct character, the whole regressive model explained variation achieved significant standard and all hypothesis have passed the statistical test. Secondly, during the tests for hypothesis with intermediary role term, the regressive coefficient intermediary variable was up to 0.723 and markedly different from 0(Sig. <0.001), the regressive coefficient of organization modularization, intellectual capital and knowledge resource were decreased respectively, determination coefficient R2 increased to 0.889 with significant higher explanation power. It shows that the regressive model with intermediary variable has influenced much on comprehensive regression effect and the hypothesis of intermediary role term have passed the statistical tests.

PL

W artykule przedstawiono analizę teoretyczną danych ze 195 dużych i średnich przedsiębiorstw produkcyjnych z 2011 roku. Wykorzystano do tego celu testy statystyczne, w tym model SEM. Zamieszczone wyniki pokazują, że zastosowany model regresyjny ze zmiennymi pośrednimi ma duży wpływ na ogólny efekt regresji. Analiza hipotezy o roli pośrednika, na podstawie dokonanych testów, okazała się prawdziwa.

12

Development of a method for comprehensive and quantitative analysis of Yohimbine in Pausinystalia yohimbe by liquid chromatography-ion trap mass spectrometry

Chen Q., Li P., Li B., Yuan F., Li X., Zhu J.

Acta Chromatographica

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2011

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Vol. 23, no. 4

629--639

EN

A rapid and sensitive method for the identification and quantification of yohimbine in Pausinystalia yohimbe is described. The method used is liquid chromatography-quadrupole ion trap mass spectrometry (LC-QIT/MS). The yohimbine standard solution was directly infused into the ion trap mass spectrometers (IT/MS) for collecting the MSn spectra. The major fragment ions of yohimbine were confirmed by MSn at m/z 355, 224, 212, and 144, in the positive-ion mode. The possible main fragment ion cleavage pathway was studied. Yohimbine provided good signals corresponding to the protonated molecular ion [M + H]+. The method is reliable and reproducible, and the detection limit is 0.1 ng mL-1. The method was validated in the concentration range 0.1–50 μg mL-1; the intra- and interday precision ranged from 1.36% to 2.73%; and the accuracy was 96.5–108.2%. The mean recovery of yohimbine was 97.1–101% with a relative standard deviation (RSD) <1.93%. The LC-IT/MS method was successfully applied to determine the yohimbine in P. yohimbe.

13

3D Measurement and Modelling of Magnetic Properties of Soft Magnetic Composite

Zhu J., Lin Z., Guo Y., Huang Y.

Przegląd Elektrotechniczny

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2009

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R. 85, nr 1

11-15

EN

The soft magnetic composite (SMC) is a new type of soft magnetic material made of insulated iron powders. Its special characteristics could enable the development of low cost high performance electrical machines. This paper presents the measurement and modelling of magnetic properties of SMC under 3D magnetizations. Detailed descriptions of the 3D magnetic property tester, principle of measurement, core loss models, and experimental results are included and discussed.

PL

Magnetycznie miękkie kompozyty (soft magnetic composites – SMC) są nowym rodzajem magnetycznie miękkich materiałów wykonanych z elektrycznie izolowanych cząsteczek proszku żelaza. Specjalne charakterystyki takich materiałów mogą umożliwić rozwój tanich i wydajnych maszyn elektrycznych. Artykuł prezentuje pomiary i modelowanie własności magnetycznych SMC w warunkach przemagnesowania 3D. Podano dokładny opis użytej techniki pomiarowej, modelu i wyników pomiarowych.

14

Spectral Energy and Age Distributions for 51 Globular Cluster Candidates

Ma J., Zhou X., Chen J., Wu H., Kong X., Jiang Z., Zhu J., Xue S.

Acta Astronomica

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2002

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Vol. 52, No. 4

453--470

EN

This paper is the fourth in a series presenting spectrophotometry of 51 globular cluster candidates, that were detected by Mochejska et al. in the nearby galaxy M33 using the data collected by the DIRECT project. The frames of M33 in this study were taken as a part of the BATC Multicolor Sky Survey. We obtained the spectral energy distributions of these candidates in 13 intermediate-band filters. By comparing the integrated photometric measurements with theoretical stellar population synthesis models of Bruzual and Charlot, we estimated their ages. The BC96 models provide the evolution in time of the spectrophotometric properties of simple stellar populations for a wide range of stellar metallicity. Our results show that half of the candidates are younger than 108 years. We also find that globular clusters formed continuously in M33 from ≈4×106 to 1010 years. Our results are in agreement with Chandar et al. who estimated ages for 35 globular clusters candidates from our list by comparing the photometric measurements to integrated colors from theoretical models by Bertelli et al. The Kolmogorov-Smirnov test shows that the maximum value of the absolute difference of estimated ages between Chandar et al. and us is 0.48, and the significance level probability is 100.00%.

15

A novel recognition method for color objects different illuminations

Wang J., Lin Z., Zhu J.

Machine Graphics and Vision

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2001

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Vol. 10, No. 1

103-112

EN

Color images depend on the scene illumination, but these image colors are not stable features for object recognition. We develop an algorithm that transforms color into its normal form such that is invariant to different illuminations. Since the normalization process is to make color image compact, solors distorted in different ways from the same object due to illumination change will all be compacted to their most compact feom and become similar. After compaction process, the histograms for the same objects under different illuminations are very similar. The recognition can be performed by simple matching method. A set of experiments on complex scenes under various other reported techniques for color normalization.