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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

A Secure Data Forwarding Protocol for Data Statistic Services in Multi-Hop Marine Sensor Networks

Wei L., Zhang K., Zhang L., Huang D.

Fundamenta Informaticae

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2018

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Vol. 157, nr 1/2

63--78

EN

Homomorphic encryption always allows the linear arithmetic operations performed over the ciphertext and then returns equaling results as if the operations are taken over the original plaintext, which is always used for data aggregation in wireless sensor networks to keep the confidentiality of the data and cut down the transmission overhead of the ciphertext. In the marine sensor networks, sensors collect the multiple data such as temperature, salinity, pressure, and chlorophyll concentration in the ocean using a single hardware unit for further statistical analysis such as computing the mean and the variance and making regression analysis. However, directly using the homomorphic encryption cannot perform well in marine sensor data forwarding since the data need to turn to satellites or vessels as relays and be forwarded in multi-hop way. The data are not expected to be decrypted until arriving the final destinations. To tackle these issues, we design a secure data forwarding protocol based on the Paillier homomorphic encryption and multi-use proxy re-encryption. We also evaluate the computational overhead in term of the delay in the transmission and operation in various test beds. The experiment results show that the additional computational overhead brought by cryptographic operations could be minor and it has the merit of providing fixed data size passing through the multi-hop transmission.

3

Dynamic compressive mechanical behaviour and modelling of basalt–polypropylene fibre-reinforced concrete

Fu Q., Niu D., Zhang J., Huang D., Wang Y., Hong M., Zhang L.

Archives of Civil and Mechanical Engineering

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2018

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Vol. 18, no. 3

914--927

EN

Dynamic compressive behaviour of basalt–polypropylene fibre-reinforced concrete (BPFRC) was experimentally investigated using a 75-mm-diameter split-Hopkinson pressure bar. The results showed that the addition of basalt fibre (BF) and polypropylene fibre (PF) is effective at improving the impact-resistance behaviour of concrete. The dynamic compressive strength, critical strain, and energy absorption capacity of BPFRC increased with increasing strain rate. At strain rates of 20–140 s−1, the addition of BF and PF significantly increased the dynamic compressive strength, critical strain, and energy absorption capacity of concrete. The dynamic increase factor of BPFRC increased linearly with the decimal logarithm of strain rate. The hybrid addition of BF and PF significantly improved the strain rate effect of the dynamic compressive strength. The strengthening and toughening mechanisms of BF and PF are discussed in detail. The proposed dynamic damage constitutive model can be used to accurately describe the dynamic stress–strain relationship of BPFRC.

4

Huang D., Qian K., Oxenham S., Fei D. -Y., Bai O.

Journal of Artificial Intelligence and Soft Computing Research

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2012

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Vol. 2, No. 2

97--108

EN

To achieve a reliable two-dimensional control by noninvasive EEG-based brain-computer interface (BCI), users are typically required to receive long-term training to learn effective regulation of their brain rhythmic activities, and to maintain sustained attention during the operation. We proposed a two-dimensional BCI using event-related desynchronization and event-related synchronization associated with human natural behavior so that users need neither long-term training nor high mental loads to maintain concentration. In this study, we intended to further investigate the performance of the proposed BCI associated with either physical movement or motor imagery with an online two-dimensional centerout cursor control paradigm. Model adaptation method was employed for better decoding of human movement intention from EEG activities. The results demonstrated an effective center-out cursor control: as high as 77.1% during online control with physical movement and 57.3% with motor imagery. It suggests that two-dimensional BCI control can be achieved without long-term training.

5

Determination of naringin and hesperidin in citrus fruit by high-performance liquid chromatography. The antioxidant potential of citrus fruit

Gorinstein S., Huang D., Leontowicz H., Leontowicz M., Yamamoto K., Soliva-Fortuny R., Martin-Belloso O., Martinez-Ayala A. L., Trakhtenberg S.

Acta Chromatographica

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2006

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No. 17

108-124

EN

Naringin and hesperidin in dimethyl sulfoxide extracts of citrus fruit (oranges, red and blond grapefruit, and sweeties – a hybrid of pummelo and blond grapefruit) have been analyzed by high-performance liquid chromatography with a mobile phase prepared from 2% aqueous acetic acid and acetonitrile. The detection wavelength was at 285 nm. Antioxidant assays based on hydrogen atom-transfer reactions (oxygen radical absorbance capacity, ORAC) and on electron transfer (total phenols by use of Folin–Ciocalteu reagent, FCR; trolox-equivalent antioxidant capacity, TEAC; ferric ion-reducing antioxidant power, FRAP; and reaction with 1,1'-diphenyl- 2-picrylhydrazyl, DPPH) were used to compare the antioxidant potential of citrus fruit and their main flavonoids. The three antioxidant assays (FRAP, TEAC, and DPPH) were performed with prolonged duration of the assay time, because all fruit extracts require long reaction times to approach the end point in the scavenging reaction. Lipophilic and hydrophilic fractions from citrus fruit were investigated by the ORAC reaction. Relationships between the main flavonoids, total polyphenols, and antioxidant potential obtained by use of the FRAP, TEAC, and DPPH procedures showed that correlation coefficients are higher for polyphenols than for the main flavonoids (as markers of 100% citrus juices). HPLC is a precise method for obtaining reliable data on the bioactivity of citrus fruit grown under the same geographical and climatic conditions. The bioactivity of citrus fruit studied by use of five different antioxidant assays was in the order sweetie > red grapefruit > blond grapefruit = orange. Hesperidin and naringin are only partially responsible for the overall antioxidant activity of citrus fruit.

6

Wide spectra characteristics of gain and carrier-induced refractive index change from measured amplified spontaneous emission spectra

Miao Q., Huang D., Wang T., Hu Z., Li P.

Optica Applicata

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2005

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Vol. 35, nr 2

377-382

EN

Based on our derived analytical equation directly relating small signal gain (SSG) with amplified spontaneous emission (ASE) of traveling-wave semiconductor optical amplifier (TWA), SSG spectra in an extended wavelength range from 1460 to 1660 nm are directly calculated from experimentally measured ASE spectra. Subsequently, carrier-induced refractive index changes for various injection currents are obtained with the same spectral range. We demonstrate the availability of our characterizing method by the determination of wide spectra characteristics from a bulk TWA with angled facets.

7

Simultaneous demonstration on 10 Gb/s wavelength conversion four-wave mixing and cross-gain modulation in semiconductor optical amplifier

Li Peili, Zhang X., Zheng Z., Huang D.

Optica Applicata

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2004

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Vol. 34, nr 1

43-49

EN

A study is presented on wavelength conversion in semiconductor optical amplifier (SOA) when the power of the input pump light is as much as that of the input signal light, in which the four-wave mixing (FWM) effect and the cross-gain modulation (XGM) effect occur obviously at the same time and the modulation format of the converted signal light is inverted to that of the input signal light. Experimental results are in agreement with theoretical analysis

8

Rotund Points, Nested Sequence of Balls and Smoothness in Banach Spaces

Bandyopadhyay P., Huang D., Lin B-H.

Annales Societatis Mathematicae Polonae. Seria 1: Commentationes Mathematicae

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2004

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Vol. 44, nr 2

163-186

EN

In this work, we continue our study of rotund points and, inter alia, show that various characterizations of strict convexity of X* like Vlasov's Theorem or Taylor-Foguel Theorem are locally consequences of properties of rotund points- a notion strictly stronger than extreme points. We observe that rotund points are a special kind of exposed points and obtain similar characterizations of wALUR and ALUR points. We characterize smooth, very smooth and Frechet smooth points in terms of straight unbounded nested sequences of balls. Various related notions are also studied in the local form.