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Artificial Neural Networks Applied to Gas Mixture Analysis

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Chinese Chemical Letters 1997年第7期8卷 623-626页

作者： Yong Jing LIN Er Yi ZRU Peng Yuan YANG(The laboratory of analytical science,xiamen university xiamen 361.05) xiamen UNIV SCI ANALYT LABXIAMEN 361005PEOPLES R CHINA

An array composed of sixteen gas sensors was constructed to analyze gas mixtures quantitatively. The data of responses from the sensor array to ethane, propane and propylene were treated by three-layer ANN with BP algorithms and PLS. The analytical results indicated that the concentration predicted with ANN is better than that with PLS. The average prediction errors for ethane, propane and propylene were 5.11%, 8.28%, 2.64%, respectively.

关键词： Wang Artificial Neural Networks Applied to Gas Mixture Analysis

Progress in the development of techniques based on light scattering for single nanoparticle detection

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science china Chemistry 2011年第8期54卷 1244-1253页

作者： ZHU ShaoBin, WANG Shuo, YANG LingLing, HUANG TianXun & YAN XiaoMei Department of Chemical Biology, College of Chemistry and Chemical Engineering key laboratory for Chemical Biology of Fujian Province key laboratory of analytical science, xiamen university, xiamen 361.05, china 1. Department of Chemical Biology College of Chemistry and Chemical Engineering key laboratory for Chemical Biology of Fujian Province key laboratory of analytical science Xiamen University Xiamen 361005 China

Nanoparticles have recendy attracted extensive attention in view of their great potential in biomedicine and bioanalytical applications. Single particle detection via light scattering offers a simple and efficient approach for the size, size distribution, and concentration analysis of nanoparticles. In particular, intrinsic heterogeneity or rare events masked by ensemble averaging can be revealed. However, the sixth power dependence of Rayleigh scattering on particle size makes it very challenging to detect individual nanoparficles of small sizes. This article is intended to provide an overview of recent progress in the development of techniques based on light scattering for the detection of single nanoparticles.

关键词： light scattering single particle detection nanoparticles confocal correlation spectroscopy flow cytometry

CHOLESTERIC LIQUID CRYSTALLINE CHARACTER ON THE SURFACE OF CHITOSAN/POLYACRYLIC ACID COMPOSITES

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Chinese Journal of Polymer science 2001年第3期19卷 247-253页

作者： Yan-ming Dong Yu-song Wu Mian Wang Department of Materials science & State key laboratory for Physical Chemistry of Solid Surfaces, xiamen university xiamen 361.05, china xiamen Univ Dept Mat Sci Xiamen 361005 Peoples R China xiamen Univ State Key Lab Phys Chem Solid Surfaces Xiamen 361005 Peoples R China

The cholesteric liquid crystalline structure in chitosan/polyacrylic acid composite films was studied by surface techniques. A periodical lamellar-like structure was observed in the permanganic acid etched film surface by both scanning electron microscopy (SEM) and atomic force microscopy (AFM), instead of the thumb-print texture which can be detected with polarized optical microscopy. It is suggested that the periodical lamellar-like structure is induced by the etching selectivity between cholesteric layers due to different molecular arrangement on the film surface. Four kinds of perpendicular disclinations, i.e. chi --> tau (-) + lambda (+), chi --> lambda (-) + tau (+), chi --> tau (-) + tau (+) and chi --> lambda (-) + lambda (+) were found in the composite films from SEM observations. The smallest periodicity of lamellar-like structure (equals to half pitch) is 20 similar to 40 nm measured with AFM.

关键词： chitosan cholesteric order liquid crystalline fingerprint texture lamellar structure SEM AFM

Embryonic and larval development of Babylonia formosae habei (Altena and Gittenberger, 1981) (Gastropoda:Buccinidae) on china’s coast

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Acta Oceanologica Sinica 2004年第3期23卷 521-531页

作者： CHEN Yan, KE Caihuan, ZHOU Shiqiang, LI FuxueDepartment of Oceanography, key laboratory for Marine Environmental science of the Ministry of Education, xiamen university, xiamen 361.05, china xiamen Univ Dept Oceanog Key Lab Marine Environm Sci Minist Educ Xiamen 361005 Peoples R China

The development of embryos and larvae of Babylonia formosae habei living along the southeast coast of china is observed under laboratory conditions. The egg masses are laid by females on hard substrate at night and each capsule contains 100-500 eggs. Each egg is 250-280 mm in diameter. The first two cleavages of the embryo are meridional and equal, and a polar lobe is produced. Larval kidney, which only consists of a single cell, appears during the gastrula stage on each side of the embryo. The right tentacle develops prior to the left one. At 25-27℃, an intracapsulate veliger stage is reached about 4.5 d after deposition. The larvae hatch on the fifth day as swimming veligers with a shell length of 360 -500 mm. The newly hatched larva can ingest suspended algal cells from the water column and remains in the pelagic stage for 8-10 d. The newly settled juveniles are 900-1 200 mm in shell length.

关键词： Babylonia formosae habei embryo larva juvenile development

Satellite-derived surface water pCO2 and air-sea CO2 fluxes in the northern South china Sea in summer

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Progress in Natural science:Materials International 2009年第6期19卷 775-779页

作者： Yu Zhu, Shaoling Shang, Weidong Zhai, Minhan Dai State key laboratory of Marine Environmental science, xiamen university, xiamen 361.05, china [a]State key laboratory of Marine Environmental science Xiamen University Xiamen 361005 China

An empirical approach is presented for the estimation of the partial pressure of carbon dioxide (pCO2) and air-sea CO2 fluxes in the northern South china Sea in summer using satellite-derived sea surface temperatures (SSTs), chlorophyll-a (Chl a) concentrations, and wind fields. Two algorithms were tested. The first used an SST-dependent equation, and the other involved the introduction of Chl a. Regression equations were developed for summer based on in situ data obtained in July, 2004. Using the monthly average SST and Chl a fields derived from the advanced very high resolution radiometer (AVHRR) and the SeaWiFS (sea-viewing wide field of view sensor), respectively, the monthly pCO2 fields were computed. The derived pCO2 was compared with the shipboard pCO2 observations conducted in July, 2000. This resulted in a root-mean-square error of 4.6 latm, suggesting that the satellite-derived pCO2 was in general agreement with the in situ observations. The air-sea CO2 flux was further computed with the aid of the monthly mean QuikSCAT wind speed. We contend that more shipboard data are necessary for refining the empirical algorithms and reducing the uncertainty in the results.

关键词： pCO2 Remote-sensing Northern South china Sea CO2 flux

Guided elastic waves in infinite free-clamped hollow cylinders

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Progress in Natural science:Materials International 2009年第3期19卷 313-320页

作者： Liguo Tang a,b,*, Shengxing Liu a,b a Department of Oceanography, xiamen university, xiamen 361.05, china b key laboratory of Underwater Acoustic Communication and Marine Information Technology of the Ministry of Education, xiamen university, xiamen 361.05, china [a]Department of Oceanography Xiamen University Xiamen 361005 China [b]Key Laboratory of Underwater Acoustic Communication and Marine Information Technology of the Ministry of Education Xiamen University Xiamen 361005 China

Guided elastic-wave-inspection technique for hollow cylinders has received plenty of attention in recent years because of its high effciency and low cost. To apply guided elastic waves to defects detection, it is necessary to investigate the propagation of guided waves in the hollow cylinders under all kinds of boundary conditions. In this paper, the dispersion equations of torsional, longitudinal and flexural guided waves in the hollow cylinders with traction-free and clamped lateral boundaries are derived by elastodynamic theory, based on which the phase and group velocity dispersion curves of the guided waves mentioned above are obtained. And the dispersion properties of these waves are discussed in detail. The transient wave in a free-clamped hollow cylinder is simulated by the finite element method (FEM). The time-frequency distribution of the transient wave agrees well with the theoretical group velocity dispersion curves.

关键词： Guided elastic waves Free-clamped hollow cylinders Dispersion

Simultaneous Determination of Fluorescein, Rhodamine 6G and Rhodamine B in Turbid Solution by Polarization Variable-Angle Synchronous Fluorescence Spectrometry

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Chinese Chemical Letters 2000年第7期11卷 613-614页

作者： Yao Qun LI Fang QIAN Xian Zhi HUANG(Department of Chemistry and key laboratory of analytical sciences of the Ministry of Education,xiamen university, xiamen 361.05) xiamen Univ Dept Chem Xiamen 361005 Peoples R China xiamen Univ Key Lab Analyt Sci Minist Educ Xiamen 361005 Peoples R China

Polarization variable-angle synchronous fluorescence spectrometry was proposed to determine samples in turbid solution. A mixture of fluorescein, rhodamine 6G and rhodamine B was used to evaluate the technique. The background caused by scattering light was decreased remarkably. The limits of detection were 0.6 ng/ml for fluorescein, 2.3 ng/ml for rhodamine 6G and 4.1 ng/ml for rhodamine B, respectively.

关键词： variable-angle synchronous fluorescence polarization fluorescein rhodamine 6G rhodamine B

Sodium current of neurosecretory cells in the eyestalk from the shrimp Penaeus japonicus

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Progress in Natural science:Materials International 2009年第11期19卷 1493-1499页

作者： Jinshen Liu~a,Shiying Li~b,Haihui Ye~(a,*),Guizhong Wang~c a Department of Oceanography,xiamen university,xiamen 361.05,china b xiamen Institute of Medicine,xiamen 361003,china c State key laboratory of Marine Environment science,xiamen 361.05,china [a]Department of Oceanography Xiamen University Xiamen 361005 China [b]xiamen Institute of Medicine Xiamen 361003 China [c]State key laboratory of Marine Environment science Xiamen 361005 China

The properties of the inward current of medulla terminalis-X-organ(MTXO) cells isolated from the Penaeus japonicus eyestalk were studied with the whole-cell clamp technique in the presence of Ca2+and K~+ channel *** inward currents had a threshold at about -50 mV and peaked at -10 *** reversed potential(Vrev) was very close to VNa,the theoretical Nernst equilibrium potential for Na~+.Vrevfollowed VNawhen the external Na~+ concentration was varied and the currents were entirely suppressed by 30 nM tetrodotoxin (TTX),indicating that it was carried by Na~+.The smooth line of concentration-dependent inhibition of sodium currents by TTX represented the best fit with the Hill equation,yielding an IC50of 2.1±0.1 *** values of the half-maximal activation voltage Vhwere -20.6±0.5 and -19.3±0.5 mV,respectively,in the absence and presence of 2 nM *** had no significant effect on the voltage dependence of steady-state activation and inactivation of *** together,the results suggest that the inward current recorded under our experimental conditions was carried by sodium ions flowing through fast voltage-dependent Na~+ channels.

关键词： MTXO Sodium current Penaeus japonicus Patch-clamp

Bacterial community in deep subseafloor sediments from the western Pacific "warm pool"

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science china Earth sciences 2008年第4期51卷 618-624页

作者： ZHAO Jing1 & ZENG RunYing2 1 College of Oceanography and Environmental science, xiamen university, xiamen 361.05, china 2 key laboratory of Marine Biogenetic Resources, Third Institute of Oceanography, State Oceanic Administration, xiamen 361.05, china College of Oceanography and Environmental science Xiamen University Xiamen 361005 China key laboratory of Marine Biogenetic Resources Third Institute of Oceanography State Oceanic Administration Xiamen 361005 China

The bacterial community in deep subseafloor sediments at a depth of 230 cm from the western Pacific "warm pool" is studied by construction of 16S rDNA clone library and PCR-RFLP (Restriction Fragment Length Polymorphism) analysis. The results indicate that the bacterial community in these sediments is mainly composed of five groups: α-Proteobacteria, β-Proteobacteria, CFB group (Cytophaga / Flexi-bacteria / Bacteroides), Acidobacteria and gram positive bacteria, with a few genera detected in each group. The most abundant bacteria group is α-Proteobacteria, and the next is β-Proteobacteria. The dominant species in α-and β-Proteobacteria are Sphingomonas paucimobilis and Pseudomonas alca-ligenes respectively. The CFB group is simply composed of members belonging to Flavobacterium. The gram positive bacteria are rich, and mainly consists of the genus Geobacillus. The analysis of bacterial community indicates that organic matter is still abundant in the subseafloor sediments at the depth of 230 cm in the western Pacific "warm pool" . These bacteria in this deep biosphere may play an impor-tant role in the nitrogen cycle of deep sea sediments at "warm pool" .

关键词： western Pacific 'warm pool' deep subseafloor sediment bacterial community