ISSN 0253-2778

CN 34-1054/N

2013 Vol. 43, No. 2

Display Method:
Flux observation research on urban and suburban atmospheric boundary layers in Nanjing
WANG Chen, YUAN Renmin, LUO Tao, SUN Jianning, JIANG Weimei, WU Xiaoqing
2013, 43(2): 87-96. doi: 10.3969/j.issn.0253-2778.2013.02.001
In the summer of 2005 and the spring of 2006, flux measurements were twice taken in Nanjing Municipal Party School and Pukou area. Heat flux, latent heat flux, carbon dioxide flux as well as friction velocity were obtained applying the eddy-covariance (EC) technique. In order to eliminate the impact of complex terrain, a planar-fit (PF) method for tilt correction was adopted. A thorough analysis of the PF method indicated that PF coefficients are closely related to wind direction. Thus, wind directions must be taken into consideration when processing data. To be specific, winds from all directions were divided into several sectors and PF method was applied to each of them in order to generate a fitted plane for each sector. This method was named sector planar fit (SPF) as distinguished from the general planar fit (GPF) which doesnt consider wind sectors. The differences of corrected fluxes by the two methods (GPF/SPF) for the two seasons and two locations were mainly considered. It was clearly revealed that both urban and suburban flux results share a consistent trend in spring and summer; geographically, in urban areas, the corrected fluxes using SPF and GPF show obvious differences, differences are much smaller in suburban areas. Moreover, the vertical velocity w was corrected using the two methods and it was found that w also exhibits significant differences. Finally, according to the probability distribution of corrected vertical wind velocity by the two methods, it was concluded that the distribution of corrected vertical velocities by SPF is closer to normal than GPF.
Assessment of pollution characteristics of heavy metals in the sediments of Huaihe River (Anhui Section) by pollution load index
WANG Jie, LIU Guijian, FANG Ting, YUAN Zijiao
2013, 43(2): 97-103. doi: 10.3969/j.issn.0253-2778.2013.02.002
27 sediment samples of Huaihe River (Anhui Section) were collected and the contents of 7 heavy metal elements (Cu, Pb, Zn, Cr, Co, V, Mn) in the sediments were analyzed by inductively coupled plasma atomic emission spectrometry (ICP-AES). The pollution degree of heavy metals was evaluated by the method of pollution load index (PLI) proposed by Tomlinson.The results show that the Anhui Section of Huaihe River is slightly polluted on the whole, with only the stretch from Fengtai to Huainan reaching a level of moderate pollution at the PLI value of 128. The degree of heavy metal pollution is in the descent order of Cr>Co>Mn=Cu>Pb>Zn>V. Among the 7 kinds of heavy metal elements, Cr is the main pollutant of Huaihe River (Anhui Section) whose concentration is 672 times higher than the background value. This may be due to coal mining and pollutants from the emissions of power plants in the region.
Experimental and numerical simulation of bimolecular reactive transport in porous media
QIAN Jiazhong, LIU Yong, ZHANG Yong, SUN Pengtao
2013, 43(2): 104-109. doi: 10.3969/j.issn.0253-2778.2013.02.003
Chemical properties in a porous media have an important effect on solute transport. To study the solute transport affected by chemical reaction and flow rates, the properties of porous media were kept unchanged, and a case study of bimolecular reactive transport was conducted by using 1,2-naphthoquinone-4-sulfonic acid and aniline. Batch experiments and numerical simulations were conducted under different flow conditions, respectively. The main conclusions are as follows: ① The modified ADRE (advection-dispersion-reaction equation)model is feasible for bimolecular reactive transport with higher accuracy. The experimental results for reactive solute transport are in good agreement with those from the model of modified ADRE under the two different seepage velocities; the relative errors for the peak concentration of the product are 12% at 04 mL/s and 08% at 08 mL/s. ② The dispersion coefficient is identified for non-reactive transport by ADRE which can provide a technological reference to determine the dispersion coefficient for reactive transport. ③ With the increase of flow rates, the values of m decrease, while the values of β0 increase; in addition, the dispersion coefficients for reactive transport are slightly larger than that of non-reactive transport for the same solute at the same flow flux. Further mechanism study is needed.
Accuracy assessment of TH-1 satellite image geometric correction using rational function model and polynomial model
ZHU Qian, LI Xia, LI Shaofeng
2013, 43(2): 110-114. doi: 10.3969/j.issn.0253-2778.2013.02.004
Based on RFM (rational function model) and the polynomial model, the geometric correction precision of TH-1 satellite images was studied on different landforms, and the relationship between the number of GCPs (ground control points) and geometric correction precision was also studied. Experimental results show that TH-1 images have a magnitude distortion caused by optical projection; RFM can obviously improve TH-1 geometric correction precision with only a few GCPs; in the polynomial model, more GCPs can achieve higher correction precision, and 2 order can get the highest correction precision; without a parameter model, high order RFM is the best choice for TH-1 image geometric correction.
Synthesis of truncated anatase bipyramids with exposure of {111} facets
ZHOU Minghui, YANG Qing
2013, 43(2): 115-119. doi: 10.3969/j.issn.0253-2778.2013.02.005
Polyhedrons of truncated anatase bipyramids with exposure of {111} facets were hydrothermally synthesized from hydrolysis of TiF4 in the presence of NH4F, HCl, and tri-block copolymer P123 using citric acid monohydrate as a stabilizer. The phase, crystal structure, morphology, chemical composition and property of the anatase polyhedrons were characterized by various techniques of X-ray diffraction (XRD), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), scanning electron microscopy (SEM), selected area electron diffraction (SEAD), energy-dispersive X-ray spectrometry (EDX) and UV radiations, and their high performances in photo-degradation of methylene blue (MB) under alkaline conditions were specifically recognized.
Gold nanorod-triggered chemiluminescence between luminol and AgNO3 and its immunoassay applications
LIU Chunzhu, LI Na, CUI Hua
2013, 43(2): 120-127. doi: 10.3969/j.issn.0253-2778.2013.02.006
A new chemiluminescence (CL) system gold nanorods-luminol-AgNO3 was built and gold nanorods were found to exhibit higher catalytic activity towards luminol CL than gold nanospheres. CL spectra, X-ray photoelectron spectroscopy (XPS), energy dispersive X-ray spectroscopy (EDX) were used to characterize this system. The effects of various reaction conditions, the morphology and protection reagents of nanoparticles on the CL reaction were also investigated. The mechanism of the CL reaction was proposed. Finally a novel microplate-compatible chemiluminescence immunoassay based on this new CL system was developed for the determination of human immunoglobulin G (IgG) with a linear range from 25 to 1 000 μg/L and a detection limit of 153 μg/L.
Preparation of PCL/graphene composite nanofibers by electrospinning
XU Songsong, YAN Lifeng
2013, 43(2): 128-134. doi: 10.3969/j.issn.0253-2778.2013.02.007
Nanofibers of PCL/graphene composite were prepared by electrospinning the mixed suspension of PCL and graphene. The morphologies as well as thermal and mechanical properties of the as-prepared fibers were studied, and the result reveals that the structure and properties of the composites depend on the ratio of graphene to PCL, concentration, voltage, and distance of collection. The tensile strength and Youngs modulus increase by 486% and 660% when 027% graphene is added, and homogeneous nanofibers of composites can be obtained when the concentration of PCL is 11% (mass fraction), spinning voltage 28 kV, collect distance 35 cm, and spinning speed 6 mL/h.
An HPLC-ECD assay for determining epinephrine and its metabolites in a compound injection
LI Ping, ZHANG Futian, LIU Gang, ZHOU Lei, WU Shouguo
2013, 43(2): 135-142. doi: 10.3969/j.issn.0253-2778.2013.02.008
An reverse phase high performance liquid chromatography (RP-HPLC) assay coupled with electrochemical detection (ECD) for systematically measuring epinephrine, norepinephrine, epinephrine sulfonate and adrenochrome in lidocaine epinephrine injection was developed. Analyses of epinephrine, norepinephrine and epinephrine sulfonate were conducted in oxidation mode, while adrenochrome was analysed in reduction mode. Chromatographic conditions such as potential, pH and ion-pair reagent content of mobile phase and sensitivity range were optimized. The proposed method was demonstrated strictly. The method shows good linear relationship (R2=0999 9) in the linear concentration range of four analytes. The detection limit of epinephrine, norepinephrine, epinephrine sulfonate and adrenochrome is 027, 050, 020, 50 μg·L-1, respectively, and the recovery of these substances is (10034±062)%, (10016±107)%, (10026±121)%, (9797±072)% (n=9), respectively. The method is fast and simple and showed high sensitivity, precision, selectivity and recovery, and can thus be used as a quality control method for drugs containing epinephrine and related substances.
Preparation and characterization of nanoporous columnar ZrO2 films by reactive magnetron sputtering
NING Zhenzhen, YU Chuanjie, LI Ming, XIE Bin
2013, 43(2): 143-150. doi: 10.3969/j.issn.0253-2778.2013.02.009
Nanoporous columnar ZrO2 films were deposited by reactive magnetron sputtering using glancing angle deposition (GLAD) configuration. The influences of deposition angle and target-substrate distance on the optical and structural properties of ZrO2 films were investigated. It is found that the ZrO2 films fabricated using GLAD show a tilted columnar microstructure; the width of the gap between two adjacent columnar crystals is less than 100 nm; the average grain size of ZrO2 films is about 10 nm; and the orientation of some grains can be changed by changing the deposition angle. In addition, with the increase in the deposition angle or/and target-substrate distance, the porosity of ZrO2 film increases while the refractive index and the deposition rate of ZrO2 film decreases. A larger deposition angle tends to increase the column inclination angle while a longer target-substrate distance tends to decrease the column inclination angle. The refractive index and porosity of ZrO2 films deposited at deposition angle of 75° are 156 and 417%, respectively.
Preparation and testing of flexible lithium ion batteries based on spinel cathode materials
ZHONG Guobin, SU Wei, LIU Shinian, ZANG Yong, CHEN Chunhua
2013, 43(2): 151-155. doi: 10.3969/j.issn.0253-2778.2013.02.010
A novel, simple and universal technique to fabricate flexible and freestanding electrode films was introduced. Three types of lithium ion batteries LiMn2O4/Li4Ti5O12, LiNi0.5Mn1.5O4/Li4Ti5O12 and LiNi0.5Mn1.5O4/graphite were assembled and tested. Lithium ion batteries fabricated using this method have high energy density and potential applications in some special areas. In addition, this technique may also be applied to in-situ spectroscopic research of lithium ion batteries.
The two-sided empirical Bayes test of parameters for scale exponential family under weighed loss function
ZHANG Qian, WEI Laisheng
2013, 43(2): 156-161. doi: 10.3969/j.issn.0253-2778.2013.02.011
Under the weighed loss function, the two-sided empirical Bayes (EB) test of parameters for the scale exponential family was discussed. The EB test rules were constructed by kernel estimation method. The asymptotical optimality and convergence rates of the EB test rules were obtained. Finally, an example satisfying the conditions of the theorem was shown.
The empirical Bayes estimation and its superiority for error variance in normal distribution
YANG Fenghao, FENG Min
2013, 43(2): 162-168. doi: 10.3969/j.issn.0253-2778.2013.02.012
Under the conjugate prior distribution of the error variance in normal distribution and the weighted squared error loss function, the Bayes estimator was derived and the parametric empirical Bayes(PEB) estimator was constructed for the error variance. The superiority of the PEB estimation over the uniformly minimum variance unbiased estimation (UMVUE) in terms of the mean-square error (MSE) criterion was studied. In the case where the hyper-parameters of the prior distribution are completely unknown, the superiority of the PEB estimation over the UMVUE under the MSE criterion was investigated with a simulation study.
A fast algorithm for the 2-adic joint complexity of pn-periodic a binary multisequence
LI Fulin, ZHU Shixin
2013, 43(2): 169-172. doi: 10.3969/j.issn.0253-2778.2013.02.013
To determine the 2-adic joint complexity of pn-periodic binary multisequences generated by feedback shift registers with carry operation (FCSR), an algorithm was presented and its theoretical derivation was provided, which yields an upper bound for the 2-adic joint complexity of a pn-periodic binary multisequence. Under a fixed condition, this upper bound is good.