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   Science & Technology Review
2011, Vol.29, No. 11-07
08 March 2011

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卷首语

Science & Technology Review. 2011, 29 (11-07): 3-3. ;  doi:
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Abstract ( 331 )
科技风云

Science & Technology Review. 2011, 29 (11-07): 7-7. ;  doi:
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Abstract ( 341 )
排行榜

Science & Technology Review. 2011, 29 (11-07): 8-8. ;  doi:
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Abstract ( 321 )
封面说明

Science & Technology Review. 2011, 29 (11-07): 8-8. ;  doi:
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Abstract ( 305 )
科技事件

Science & Technology Review. 2011, 29 (11-07): 9-9. ;  doi:
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Abstract ( 323 )
科技界声音

Science & Technology Review. 2011, 29 (11-07): 10-10. ;  doi:
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Abstract ( 290 )
科技工作大家谈

Science & Technology Review. 2011, 29 (11-07): 11-11. ;  doi:
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Abstract ( 328 )
科学共同体要闻

Science & Technology Review. 2011, 29 (11-07): 12-12. ;  doi:
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Abstract ( 308 )
科技期刊亮点

Science & Technology Review. 2011, 29 (11-07): 13-13. ;  doi:
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Abstract ( 300 )
科技要闻

Science & Technology Review. 2011, 29 (11-07): 14-14. ;  doi:
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Abstract ( 287 )
Exclusive

Science & Technology Review. 2011, 29 (11-07): 15-21. ;  doi: 10.3981/j.issn.1000-7857.2011.07.001
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Abstract ( 349 )
Articles

Influence of Survivin Gene-targeting siRNA on the Biological Features of Colorectal Carcinoma Cells

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Science & Technology Review. 2011, 29 (11-07): 22-25. ;  doi: 10.3981/j.issn.1000-7857.2011.07.002
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Abstract ( 425 )
Survivin siRNA is transfected to colon cancer cells SW480 and the interference on proliferation and apoptosis is studied to provide the experimental basis for gene therapy of colon cancer and seek new, effective RNA interference fragment. Three siRNA targeting Survivin gene were constructed and transfected into SW480. After 24, 48, and 72h, the change of survivin protein was detected by using Western blot, in the same time, cell proliferation was detected by using MTT assay. The results show that after three siRNA effect on SW480 cells at 24, 48, and 72h, three groups of Survivin protein expression are all appeared the decrement (P<0.05). The expression of Survivin protein reached apex at 48h and the inhibitory rates were 66.5%±2.1%, 49.6%±2.8% and 47.8%±3.1%, respectively, compared with the control group (P<0.05). MTT assay show that the cell proliferation was inhibited after Survivin gene silencing. Liposome-mediated Survivin siRNA can effectively silence the Survivin gene in colon cancer cells, therefore inhibit cancer cell proliferation and promote apoptosis, it is especially designed for targeting conservative regions of siRNA, and interference effects are more significant.

Ecological Effect of Pre-flowering Light Deficit on the Rhizosphere Soil Microbes of Rice

Science & Technology Review. 2011, 29 (11-07): 26-30. ;  doi: 10.3981/j.issn.1000-7857.2011.07.003
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Abstract ( 429 )
The aim of this study is to investigate the ecological effect of pre-flowering light deficit on the rhizosphere soil microbes of rice and provide the guidelines for the benign ecological cycle of soil and for the cultivation practice of super rice in light-poor areas. A super hybrid rice combination, "II Youhang 2", was used in the experiment under the field condition. Two shading intensities of 55% and 85% were set from jointing stage to initial heading stage in the experiment. The natural light condition was taken as the control. The results show that the amount of bacteria, actinomycetes, ammonifier, nitric acid bacteria, and aerobic azlotobacter has significantly declined with light deficient treatments at booting, initial heading, grain-filling, and harvest; in the meantime, the amount of fungi and denitrifier as well as desulphate has enhanced, and it results in the descent of the content of soil microbial metabolic biomass carbon and nitrogen. The factors inhibit the activities of soil urease and acid phosphatase. Moreover, the amount of bacteria, actinomycetes, ammonifier, nitric acid bacteria and aerobic azlotobacter is going down with the increasing intensity of light stress, and mutative trend of soil microbial metabolic biomass carbon and nitrogen, soil urease, and acid phosphatase is the same. However, the behavior of fungi and denitrifier as well as desulphate reducer are quite opposite to bacteria and actinomycetes. It is implied that pre-flower light deficit drops drown soil microbial metabolic biomass, alters soil microbial community, and undermines rhizosphere micro-ecological environment of the growth of rice.

Building Urban Underground Environment Freight Transportation System Based on Underground Container Transportation

Science & Technology Review. 2011, 29 (11-07): 31-35. ;  doi: 10.3981/j.issn.1000-7857.2011.07.004
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Abstract ( 491 )
City waste crisis, land resource exhaustion, urban traffic congestion, and ecological environment deterioration have seriously hindered the modern urban sustainable development. By describing "waste crisis", it is revealed that the increasing quantity of waste output, the insufficient waste disposal capacity, and the unreasonable waste collection and transportation methods are the cause for the problem of "waste siege" in many big cities. In addition to waste classification and "reduce, reuse, recycle" policy, an effective method for solving waste crisis is to improve the waste disposal capacity as well as the collection and transportation method. Furthermore, the concept of underground environment freight transportation is explained, and plan and conceptual design of urban underground domestic waste transfer logistics system in Shanghai are introduced. It is pointed out that the underground environment freight transportation system provides an important and feasible way to relieve the waste crisis. Besides, underground environment freight transportation system can reduce traffic congestion, improve urban environment, lead to related high-tech researches, and promote the sustainable development of modern cities.

Identification of the Diabase in the Northern Slope of Gaoyou Sag and Determination of Its Formation Period

Science & Technology Review. 2011, 29 (11-07): 36-41. ;  doi: 10.3981/j.issn.1000-7857.2011.07.005
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Abstract ( 560 )
Diabase intruded into multi-horizon of the northern slope of Gaoyou Sag makes the structural conditions and the petroleum geology conditions of broken block area more complex. The formation period of diabase closely related to the hydrocarbon reservoir formation has become a deeply concerned problem. Diabase is identified and interpreted by core observation, thin section identification, well-drilling, well-logging, and seismic data, it shows that logging response characters of the diabase in the northern slope are low natural gamma ray, low acoustic, low neutron porosity, high density, and high resistivity, its characteristics with the seismic reflection profiles are low frequency, strong amplitude, and good continuity, the upper sets of diabase are intruded into the fourth member of Funing Formation to Sanduo Formation and the lower sets of diabase are intruded into the second member to the third member of Funing Formation. Based on the above facts, with fault distribution of the corresponding period, the analysis results indicate that distribution range of the upper sets of diabase is more centralized, and is mainly along the major faults in north east direction and east west direction, and the lower sets of diabase is more extensive, and is obviously controlled by the transfer zone of major faults. According to the isotopic dating, and by comprehensively consideration of every factor involving spreading range, distribution characteristics of thickness, and tectonic activity of different stages, it is concluded that the upper sets of diabase are the products of Sanduo Event, and the lower sets of diabase are the products of Wubao Event and Sanduo Event.

MA Transmutation Strategy

Science & Technology Review. 2011, 29 (11-07): 42-45. ;  doi: 10.3981/j.issn.1000-7857.2011.07.006
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Abstract ( 413 )
According to the development plan envisagement for nuclear power plant in China, the development of China's nuclear power in the next decades is predicted with the nuclear fuel cycle software NFCSS provided by IAEA. The amounts of the spent fuel generated and accumulated by the year of 2050 are analyzed. According to the assumption model, the accumulated spent fuel by the year of 2050 will reach at 54791t including 57.89t Minor Actinides (MA) (237Np, 42.91t; Am, 11.17t; Cm, 3.81t) and 2778t FP. One group effective cross section of MA in the thermal, well thermalized, and fast neutron field is calculated based on ENDF/B-VII nuclear evaluation database. The transmutation way for three main MA, i.e. 237Np, 241Am, and 246Cm is also analyzed. It is more suitable for 237Np transmutation in well thermalized neutron field and for 241Am, the high flux thermalized neutron field is better. But it is difficult for 246Cm transmutation in thermal or fast neutron field due to its little fission cross section. Its transmutation ability can be improved if transmutation occurs in a high fluxes resonance energy area. The two-stage transmutation strategy is presented according to their characteristics in the thermal, well thermalized, and fast neutron field. Based on the two stage transmutation concept, the transmutation is performed in a well thermalized neutron field first. Small amount of residual of the first stage transmutation is transmuted in a thermal field with a spectrum. It is expected to achieve a good result.

Band Structure of 2D Air-hole-type Triangular Photonic Crystal with Oblique Incidence

Science & Technology Review. 2011, 29 (11-07): 46-49. ;  doi: 10.3981/j.issn.1000-7857.2011.07.007
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Abstract ( 450 )
The eigenmatrix of the light propagation in photonic crystal are deduced by the plane-wave expansion method. The dispersion curves of two dimensional square lattice and triangle lattice photonic crystals composed of circular air cylinders are calculated by numerical calculation, respectively for vertical incidence. And the dispersion curves of triangle lattice photonic crystals also are calculated for oblique incidence. Based on the calculation and analysis, it is indicated that the band gaps of E wave and H wave of two dimensional triangle lattice in <10> direction and <11> direction for vertical incidence all appear, and they are wider than that of square lattice; the dispersion curves of two-dimensional triangular photonic crystal in the oblique incidence are moved upward with the angle of incidence increasing, and band gap center frequency also increased, however the band gap width has been reduced accordingly until it disappeared. These studied results are significant for making photonic crystal elements and putting them into applications.

DEM Accuracy Assessment Based on M-Estimation

Science & Technology Review. 2011, 29 (11-07): 50-54. ;  doi: 10.3981/j.issn.1000-7857.2011.07.008
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Abstract ( 404 )
The report on of DEM accuracy is commonly based on some global statistical measures, such as the mean and standard deviation of DEM errors. Usually, the specification of these accuracy indices is based on the assumption that the error distribution is normal and there is no outlier and systematic error. However, such an assumption is rarely an exact statement owing to the malfunction or improper calibration of instruments, mistaken readings, gross recording and calculation, and improper execution, etc, particularly when a DEM is directly derived from digital photogrammetric systems and active airborne sensors including Light Detection and Ranging (LiDAR) and InSAR. A robust estimator based on the adaptive M-estimation principle (REMP) has been developed for the DEM accuracy assessment. The iteration of REMP starts from estimations with a high breakdown point and selection of the weights of errors with the residual distribution. In terms of DEM mean and standard deviation errors, two examples including a numerical test and a real-world one were employed to comparatively analyze the results of REMP and the classical non-robust and robust estimators. Results indicate that under the non-normal distribution of DEM errors, the classical non-robust estimators are seriously influenced by the non-normality. Some robust estimators, such as 10% trimmed or Winsorized mean, normalized median absolute deviation are not very robust to resist the influence of outliers. REMP that is slightly affected by the non-normal distribution of DEM errors is more accurate than the classical estimators. The robust methodology can adapt to the DEMs, especially the ones derived from remote sensing, such as LiDAR or digital photogrammetry in the non-open terrain.

Tow Parameters Algorithm for Solving the Quasi-pentad-diagonal Linear Equations Set

Science & Technology Review. 2011, 29 (11-07): 55-57. ;  doi: 10.3981/j.issn.1000-7857.2011.07.009
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Abstract ( 1133 )
An algorithm is presented for solving quasi quinque-diagonal linear system of equation. First, the last two variables are selected as the parameters and are put into the other n-2 equations. Then the original problem can be transformed into a problem for solving three quinque-diagonal linear systems of equation. Finally, all the solution vectors can be obtained by solving the parameters xn-1 and xn. A forward elimination and backward substitution algorithm is used to solve the quasi quinque-diagonal linear system, it shows a good numerical stability. Experimental data indicate that comparing with the four parameter algorithm, not only the two parameter method is fast for solving the same order of linear equations with time ratio of about 1.47, but also the memory consumption is less than that used by the four parameters. The measure of multiplication or division in this algorithm is O(23n) and O(16n) for addition and subtraction, respectively. The
memory needed is about O(10n). The number of arithmetical operations and memory consumption all have a linear relation with the n.

Thermal Degradation Mechanism and Pyrolysis of thePolycaprolactone

Science & Technology Review. 2011, 29 (11-07): 58-61. ;  doi: 10.3981/j.issn.1000-7857.2011.07.010
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Abstract ( 567 )
The Polycaprolactone (PCL) cast film was made using purified PCL, the purified CHCl3 acted as solvent. The specimen was investigated by using modulated thermogravimetry analysis, the structure of low molecular compounds were determined by NMR and FTIR. It can be found from results of modulated TGA that the PCL pyrolysis had two steps, the decomposition temperature and the weight loss rate in the first step were 205~295℃ and 7.0% respectively, while in the second were 311~374℃ and 88%. At the same time the Ea, Z and ln[rate ratio] be got, in the first step the results were respectively 80kJ/mol, 5min-1 and 0.3, as in the second were 146kJ/mol,
11min-1 and 0.47. And the result of the NMR and FTIR suggested that during the pyrolysis process, not only be get macromoleclar PCL, but also the furan, cyclopropanes displaced unsaturation carboxylic acid were produced.

Voice Communication Encryption Application of Oversampled Chebyshev Chaotic Sequences

Science & Technology Review. 2011, 29 (11-07): 62-65. ;  doi: 10.3981/j.issn.1000-7857.2011.07.011
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Abstract ( 394 )
With the development of the multimedia and digital communication, people obtain increasingly more information and communicate with each other much more easily. For protecting information from eavesdropper, the encryption processing for large amounts of data is necessary. Although there are different demands for the encryption algorithm in different applications, however the demand for security and speediness are common. By studying the characteristic of chaotic system, a communication encryption program with high speed and security is designed. To construct encryption algorithm, some improvement has done on the chaotic iteration process according to the characteristic of digital chaotic, the oversampled to the Chebyshev chaotic maps (OSCM) is realized. Also, voice signal transmission systems were designed to encrypt the original voice signals by using the oversample of chaotic sequence at the sending port. After the modulation, the signals passed through the AWGN channel. The encrypted voice signals are demodulated and decrypted after receiving the ciphertext at the receiving port, and then the decrypted voice signal are received. Experiments show that the application of over sampling technology in the chaotic spread spectrum communication can greatly increase the confidentiality of wireless communications.

Wind Speed Combination Forecasting Model Based on Least Square Support Vector Machine

Science & Technology Review. 2011, 29 (11-07): 66-68. ;  doi: 10.3981/j.issn.1000-7857.2011.08.012
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Abstract ( 453 )
In order to study the feasibility of combination forecasting model based on least squares support vector machine for wind speed short-term forecasting, the forecasting data coming from Back Propagation (BP) neural network, Radial Basis Function (RBF) neural network, and Particle Swarm Optimization neural network (PSOBP) were used as inputs and the actual wind speed was used as output in this model. The least squares support vector regression algorithm is used for constructing the nonlinear relationship in order to achieve multi-step forecasting for wind speed. The forecasting performance of the model is compared with BP combination forecasting model and linear combination forecasting model, and it was evaluated by mean absolute error, sum of squared error, and average relative error. The results indicate that the average relative error for least squares support vector machine prediction model is less than 6%; and the rest of error indicators for it are significantly lower than other models. Therefore its forecasting accuracy is not only better than any other single forecasting model, but also better than the traditional linear combination forecasting model. It validates the feasibility of least squares support vector machine combined forecasting model for wind speed forecasting.

Multi-hierarchical Grey Evaluation System for Urban Community Disaster Mitigation Capability

Science & Technology Review. 2011, 29 (11-07): 69-73. ;  doi: 10.3981/j.issn.1000-7857.2011.07.013
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Abstract ( 797 )
In the recent years, emergencies happen frequently in China, therefore the research on emergency management has been paid more attention by many scholars. The emergency management process is divided into four periods which are mitigation, preparation, replying, and resuming based on classic emergency management cycle theory. The concept of "disaster mitigation capability" is systematic, comprehensive, and theoretical; as a result, deep study on it has a high theoretical value. The related literature study shows that there are few systemic researches aiming at emergency mitigation capability of urban communities. Based on the present developing process and emergency features of urban communities, building and applying the evaluation system for urban communities' disaster mitigation capability has the important theoretical and practical value to the safety of urban communities and the consistent development of society. The evaluation system builds on three parts of theories; they are emergency management theory, "the preparation community" theory, and "the resuming community" theory. The evaluation system of disaster mitigation capacity has been built based on the emergency management, including six first-level indexes and 25 second-level indexes, and the analytic hierarchy process and grey system theory is applied to build multi-hierarchical grey comprehensive evaluation model in order to quantitatively evaluate disaster mitigation capacity of urban communities. Based on the model and the computation result of the example of Longyuanhu Community of city Jiaozuo in Henan Province, it is shown that the disaster mitigation capacity of the community is between good and not bad, and the disaster deduction of emergency management in communities needs to be strengthened. The comprehensive evaluation model provides the useful consideration for improving disaster mitigation capacity in urban communities.
Reviews

Development and Future Prospects of Millimeter-VLBI

Science & Technology Review. 2011, 29 (11-07): 74-79. ;  doi: 10.3981/j.issn.1000-7857.2011.07.014
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Abstract ( 1301 )
Very Long Baseline Interferomety (VLBI) is a high-resolution imaging technique in radio astronomy. It has made substantial contribution to our understanding of Active Galactic Nuclei (AGN). The progress in VLBI is reviewed focusing on the development at millimeter wavelengths and its applications to AGN studies. Extending this technique to millimeter wavelengths, so-called mm-VLBI, leads to a unique opportunity to directly probe the central regions of AGN with the highest angular resolution in astronomy. Direct imaging of the jet innermost regions is indispensable for answering a number of unresolved fundamental questions regarding the jet formation, acceleration, and collimation. It is also a key to understand how the gravitational effects and magnetic fields (through full polarimetric VLBI observations) play the role in the vicinity of Super Massive Black Holes (SMBH). Such kind of studies are not possible at centimeter wavelengths due to the self-absorption, opacity, Faraday depolarization and scattering (in the case of Sgr A*) effects. In addition, millimeter-VLBI observations also open windows to study new species of spectral lines with unprecedented angular resolutions. The present challenges of millimeter VLBI are explained and a brief developing history is then described. Recent technical development allows imaging of hundreds of sources at 86GHz with high dynamic range. At even higher frequencies, studies are at present limited to pilot experiments, but have shown the detectability of brightest AGN and the existence of event-horizon-scale structures. These studies provide us with direct insights into black hole and relativistic jet physics. The future potential for improvement in mm-VLBI detection sensitivity is summarized. The characteristics for those radio telescopes and interferometer arrays, which are likely available in the next few years for global VLBI at short millimeter wavelengths (≤1.3mm) are presented. With the addition of these new instruments, a detailed imaging of nearby SMBHs (e.g. Sgr A*, M87) and answer to the open question of jet formation can be prospected.
书评

Science & Technology Review. 2011, 29 (11-07): 80-80. ;  doi:
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Abstract ( 343 )
科技纵横捭阖

Science & Technology Review. 2011, 29 (11-07): 81-81. ;  doi:
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Abstract ( 355 )
读者之声

Science & Technology Review. 2011, 29 (11-07): 82-82. ;  doi:
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Abstract ( 298 )
主编心语

Science & Technology Review. 2011, 29 (11-07): 83-83. ;  doi:
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Abstract ( 320 )
走向职场

Science & Technology Review. 2011, 29 (11-07): 84-84. ;  doi:
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Abstract ( 352 )

Science & Technology Review. 2011, 29 (11-07): 85-87. ;  doi:
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Abstract ( 308 )

Science & Technology Review. 2011, 29 (11-07): 88-91. ;  doi:
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Abstract ( 290 )
智力休闲

Science & Technology Review. 2011, 29 (11-07): 92-92. ;  doi:
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Abstract ( 288 )

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