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   Science & Technology Review
2010, Vol.28, No. 06
28 March 2010

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Development and Trend of China Meteorological Satellite

Science & Technology Review. 2010, 28 (06): 3-3. ;  doi:
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Abstract ( 415 )
特别栏目

Science & Technology Review. 2010, 28 (06): 8-8. ;  doi:
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Abstract ( 359 )

Science & Technology Review. 2010, 28 (06): 8-8. ;  doi:
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Abstract ( 367 )

Science & Technology Review. 2010, 28 (06): 10-10. ;  doi:
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Abstract ( 418 )

Science & Technology Review. 2010, 28 (06): 12-13. ;  doi:
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Abstract ( 410 )

Science & Technology Review. 2010, 28 (06): 14-15. ;  doi:
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Abstract ( 367 )

Science & Technology Review. 2010, 28 (06): 16-17. ;  doi:
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Abstract ( 411 )

Science & Technology Review. 2010, 28 (06): 125-125. ;  doi:
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Abstract ( 393 )

Science & Technology Review. 2010, 28 (06): 138-138. ;  doi:
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Abstract ( 381 )

Science & Technology Review. 2010, 28 (06): 139-139. ;  doi:
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Abstract ( 371 )
半月科技风云

Science & Technology Review. 2010, 28 (06): 9-9. ;  doi:
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Abstract ( 454 )
科技事件

Science & Technology Review. 2010, 28 (06): 11-11. ;  doi:
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Abstract ( 395 )
科技工作者建议

Science & Technology Review. 2010, 28 (06): 18-18. ;  doi:
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Abstract ( 439 )
Exclusive

The Origin and Development of Academic Conferences

Science & Technology Review. 2010, 28 (06): 19-24. ;  doi:
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Abstract ( 590 )
Academic conferences are closely related with the communication and innovation in science and technology. In the early stage of scientific development, academic conferences were in a shape of academic gatherings without a definite form. With the development of modern science, academic conferences were gradually institutionalized, and the purpose, form and function took some formats, with unique characteristics. The academic conferences, on the other hand, become more diversified in forms, with objectives specialized and with the process, the function, the organization and the management standardized, socialized and internationalized.. Academic conferences play an increasingly important role in the promotion of the academic prosperity and the scientific development, From the 1900s' to the 1950s' or the 1960s', academic conferences were in an important period for industrialization. The objectives, organization forms, communication modes, running processes and culture atmosphere are constantly changing with a new connotation. Along with the process of science gradually taking root in China, the academic conferences in China have also developed. Since the late 20th century, they have been in the boom with high quality requirements. Future academic conferences see the principal trends of specialization, information, boutique-oriented, practical, international, equal rights, joint-oriented, marketing-oriented.
Articles

Some Notes on Mersenne Primes

Science & Technology Review. 2010, 28 (06): 25-28. ;  doi:
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Abstract ( 535 )
A Mersenne prime is a Mersenne number that is a prime. It is known that if 2p-1 is a prime, p will also be a prime, therefore, it makes no difference which definition of Mersenne number is used. The Mersenne prime has long fascinated both amateur and professional mathematicians. It is always an important topic in the number theory and also one of today's hot and difficult scientific problems. Mersenne primes, as usually the largest known primes, are both rare and beautiful. As of January 2010, only 47 Mersenne primes are known. Lucas-Lehmer test is the fastest and most effective tool for determining the primality of Mersenne numbers. Zhou conjecture is the well-known problem of the distribution of Mersenne primes. This paper first discusses three important problems related with Mersenne primes. Then from the recursive sequence of Lucas-Lehmer test, a special nature of the derivative series is shown, a related guess is made; a correlation equation of Lucas-Lehmer test is obtained, the relevant guess is made from the type of the close relationship between the speculation and Zhou conjecture; and the problem of existence of the generalized Lucas-Lehmer test is formulated, together with a related guess. The results show a good prospect in the studies of Mersenne primes.

Quenching Phenomena for a Quasilinear Parabolic Equation with Nonlinear Source

Science & Technology Review. 2010, 28 (06): 29-31. ;  doi:
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Abstract ( 497 )
For many quasilinear differential equations, their origin may be traced in biology and astrophysics, as related with generalized reaction diffusion theory, non-Newtonian fluid theory, non-Newtonian filtration theory and the turbulent flow of a gas in porous medium. Quenching phenomena for a class of quasilinear parabolic equations are studied in this paper. In the time domain, nonlinear parabolic equations not necessarily have a continuous solution. For some equations, solutions exist as a whole, for others solutions may not exist. Quenching phenomena are related with cases where solutions do not exist in some time period. This paper considers the extinction of solutions of an initial boundary value problem of the quasilinear parabolic equation ut-div[?滓(|?荦u|2)?荦u]=?姿up in a bounded convex domain of RN with N≥2. This problem is first introduced in the field of geometry. At this time, the principal part of the equation is no longer uniformly elliptic. Using upper and lower solutions and the integral estimate method, two results of the extinction of the solution are obtained. The results obtained can be extended to a more general form of quasilinear parabolic equations.

A Method in Regulating the Consistency of the Judgment Matrix

Science & Technology Review. 2010, 28 (06): 32-34. ;  doi:
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Abstract ( 495 )
While making decision by Analytic Hierarchy Process (AHP), the consistency of judgement matrix must be checked. If it can not pass the test, some entries of the judgement matrix should be adjusted, and the consistency should be tested again. Accordingly, it is important to find methods regulating the consistency of the judgment matrix. However, with many such methods, the variations of many entries are too great, and the number of adjusted entries are too large, as is not very convenient for decision-makers. This paper proposes a method for regulating the consistency of the judgment matrix, where the revision and the identification of error-elements are based on the maximum deviation of the related element to the arithmetic mean obtained from multiplying a row vector by a column vector. This method can better describe the information of the original judgment matrix, and the threshold of the regulation can also be pre-established. The unreasonable elements can be identified easily, efficiently and quickly. The computation is simple, and the regulation can be done manually or by computer.

Modeling and Simulation of Spiral Stirrer for Asphalt Conveyor Based on Hybrid PSO Algorithm

Science & Technology Review. 2010, 28 (06): 35-38. ;  doi:
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Abstract ( 506 )
To overcome the difficulty of modeling for agitation characteristics of spiral stirrer for asphalt conveyor, a Neural Network (NN) model was established, based on both pitch and radius of helical blade being used as the input vector, with the rate of mixture segregation used as the output vector of NN. To avoid the shortcomings of the Back Propagation (BP) algorithm and the Particle Swarm Optimization (PSO) algorithm, a hybrid PSO algorithm PSOLM was employed as the learning algorithm of NN, which was combined with Levenberg-Marquardt (L-M) algorithm. To avoid the slow search speed reated with the global optimum in the PSO-BP algorithm, a heuristic way was adopted to give a transition from the particle swarm search to L-M search. Simulation experiment was performed with model experiment for asphalt conveyor. The results of simulation and experiment show that the proposed approach not only has faster convergence and higher computational precision than the original PSO, but also can overcome the drawbacks of BP algorithm. It is also a new and effective approach for model building of spiral stirrer agitation characteristics.

Exact Analytical Solutions of a Ratio-dependent Capture Predator-Prey System with Holling Type III

Science & Technology Review. 2010, 28 (06): 39-41. ;  doi:
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Abstract ( 1252 )
The predator-prey relationship is not only a fundamental relation between species in nature, but also very important in ecology and bio-mathematics. In most research fields, which deal with definite objects, the traditional approach is to derive some basic rules based on experiments and observations, then to obtain mathematical equations and their analytical solutions. Numerical solutions are commonly required due to the difficulties to obtain analytical solutions. But analytical solutions have important merits in theory, especially as the benchmark solutions to check the accuracy, the convergence and the stability of various numerical computational methods and to improve their difference schemes, grid generations and so on. Some exact analytical solutions of a ratio-dependent capture predator-prey system with Holling type III functional response are derived in this paper. They can be used as the benchmark solutions to verify the numerical solutions and even to develop various numerical methods.

Improved Listless SPIHT Based Image Compression Algorithm

Science & Technology Review. 2010, 28 (06): 42-45. ;  doi:
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Abstract ( 1190 )
The algorithm of Set Partitioning in Hierarchical Trees (SPIHT) is well known for its simplicity and efficiency. However, the use of three lists(LSP, LIP and LIS list) requires a high, variable and data dependant memory. Besides this, a repeated scanning also reduces the algorithm's efficiency to make it difficult for the SPIHT algorithm to be implemented in a hardware platform, especially for low memory and real time applications. In order to solve this problem, a modified listless SPIHT based algorithm is proposed in this paper. Firstly, the state mark matrixes are used to replace three lists (LSP, LIP and LSP list) for the significant information, and the modified SPIHT algorithm saves memory and avoids the dynamic memory management. The use of the maximum value array and the number of the maximum output bits also reduces the degree of scanning in the sorting pass and enhances the algorithm's efficiency. Secondly, in the modified SPIHT algorithm a new test is added for the type A set to optimize the output bit stream, which improves the algorithm's performance.

Effects of 5’-nucleotides on Modulation of Adaptive Immunity of Mice

Science & Technology Review. 2010, 28 (06): 46-49. ;  doi:
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Abstract ( 619 )
To study the effects of 5'-nucleotides on modulation of adaptive immunity of mice and to determine the best dosage, female BALB/c mice were administered with common control diet, Nucleotides-Free(NF) diet and NF diet with 0.0025%, 0.01%, 0.04%, 0.16% 5'-nucleotides for 4 weeks. Cellular immune functions, humoral immune functions, the level of immunoglobulin in serum and splenic T cell subpopulations of the spleen tissue by the flow cytometer were examined. The results show that with the NF diet, the capacity of lymphocyte proliferation induced by ConA (0.06±0.03) and DTH response (0.12±0.06)mm are significantly reduced; the ratio of CD4+/CD8+ is decreased (1.90±0.12) while Tr percentage is increased (5.56±0.11). A decrease trend of B lymphocytes antibody response was observed. The NF diet with 5'-nucleotides can prevent these decreases. At the dose of 0.04%, the immunological functions are increased significantly as compared with those of NF group, reaching normal values. The results indicate that the NF diet can impair the immunological function of mice, while the NF diet with 5'-nucleotides can prevent the decrease, and 0.04% is the best dose.

Effect of the Recombinant Human Erythropoietin on MMP-9 Expression in Astrocyte After Hypoxia Cultured

Science & Technology Review. 2010, 28 (06): 50-54. ;  doi:
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Abstract ( 551 )
To investigation the effect of recombinant human erythropoietin preconditioning on the injury of astrocytes and the expression of MMP-9 after hypoxia, cerebral cortical astrocytes, newborn SD rat within 2 days were collected with the pure culture and the astrocytes were divided into control group, hypoxia group and rhEPO preconditioning group. The survival rate of astrocytes of 12h, 24h and 36h were determined by MTT assay. Inverted microscope and transmission electron microscope were used to observe the cell changes. The expression of MMP-9 mRNA and protein of astrocytes were detected by immunofluorescence and RT-PCR. It is shown that the astrocytes were swelled after hypoxia cultured 12h, with the maximal cell swelling observed at 36h. The rhEPO preconditioning can reduce the cell swelling remarkably. Ultrastructural alterations of astrocytes such as mitochondrial swelling after hypoxia can also be alleviated remarkably by rhEPO preconditioning. The results of MTT assay show that the survival rate of rhEPO preconditioning group were obviously higher than that of the hypoxia group(P<0.05). RT-PCR and immunocytochemistry analysis confirm that the expression of MMP-9 mRNA and protein was remarkably increased at 12h, peaked at 24h and declined at 36h after hypoxia cultured. Compared with hypoxia group, the expression of MMP-9 mRNA and protein in the rhEPO preconditioning group was significantly lower at 12h, 24h and 36h(P<0.05). The results show that rhEPO can improve the survival rate of astrocytes under hypoxia by inhibition of MMP-9.

Measurement of Hemorheology Parameters Based on the Light Scattering

Science & Technology Review. 2010, 28 (06): 55-57. ;  doi:
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Abstract ( 498 )
Light scattering can be applied in experimental detection through capturing scattering spectrums from tested objects, to obtain vast amount of information related to those objects. In particular, by capturing Raman and Brillouin scattering spectrums, high precision information can be obtained. This kind of detection enjoys various advantages such as non-toxic, non-traumatic, prompt in detecting, and accurate with respect to data gathering. Therefore, when this method is applied on medical clinical trails, besides obtaining accurate testing data, patient's sufferings can largely be alleviated as well. Hemorheology parameter detection is an application of this methodology in medical science. As a preliminary study, prophase classification tests are normally adopted before the regular hemorheology parameter detection. This paper presents studies on prophase classification tests, including installation of experimental light path, set up of testing devices, and exploration of experimental methods.

Sequence-stratigraphic Framework on Paleogene of the Liaohe Western Depression

Science & Technology Review. 2010, 28 (06): 58-64. ;  doi:
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Abstract ( 496 )
With the development in depth of the oil and gas exploration, the exploration of the Liaohe western depression becomes more and more difficult, and serves as a complex challenge in view of petroleum geology. In order to undertake the fine and three-dimensional exploration of the oil and gas in the western depression and to increase the success rate of exploration, it is necessary to learn the successful exploration experience from Jidong oilfield, Jilin oilfield and Shengli oilfield, and to carry out detailed exploration of oil and gas in the western depression. The establishment of a sequence-stratigraphic framework is essential for the fine exploration of the oil, and of great theoretical and practical significance. Guided with the theory of sequence stratigraphy and based on well drilling, well logging, seismic and palaeophyte data in the interested districts, the paleogene can be divided into 4 second-order sequences and 11 third-order sequences on the basis of the identification of the sequence boundary which is made through unconformity surface recognition in the seismic section, isochronal formation comparison of the palaeontology fossil and mutation surface recognition of the well logging curves. According to the sequence boundary and the division of layer cells, and by using the synthetic seismogram, the sequence-stratigraphic framework of the west depression is established. Sedimentary sequence distribution law in the sequence-stratigraphic framework includes 5 aspects: migrated southward depocenter; thin slope sedimentary; large sedimentary thickness in the south and small sedimentary thickness in the north, a complete formation in the low-lying; and a not completed formation in the heave part.

Study on the Weathering Characteristics of Tertiary Pelitic Siltstone

Science & Technology Review. 2010, 28 (06): 65-68. ;  doi:
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Abstract ( 526 )
To study the weathering characteristics of tertiary pelitic siltstone, each silty mudstone with different weathering degrees is analyzed in many different experimentations. The researching fields involve its engineering characteristics, weathering durability and weathering speed. The engineering characteristics were revealed by testing mineral composition, chemical composition and mechanical properties of rock mass with different weathering degrees. The weathering durability was shown by testing compressive strength and slake durability of different rock samples. The weathering speed was determined in four different experimental conditions for the weathering rock. The test results show that with the growth of weathering degree of the rock mass, the content of clay minerals in the rock mass increases, the chemical composition with high activity in the rock mass decreases relatively, the dry density of the silty mudstone decreases, the total porosity and the water absorption rate of the silty mudstone increases, the mechanical properties are weakened, and the rock mass becomes easy to soften and collapse. At the same time, the weathering speed of the rock mass is related to the weathering degree and the exposed area of the rock mass. The research findings provide some theoretical basis for understanding the Tertiary Pelitic Siltstone and solving related problems in practical engineering.

Characteristics of Hydrocarbon Reservoirs in the Post-salt Strata in Block Sagizski, Pre-Caspian Basin

Science & Technology Review. 2010, 28 (06): 69-77. ;  doi:
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Abstract ( 718 )
The hydrocarbon accumulation in Pre-Caspian Basin is closely related to the territorial salt in Kungurian of Early Permian. Block Sagizski in the southeast Pre-Caspian Basin is rich in hydrocarbon. The main exploration target is the Post-Salt Strata (including the strata over and between salt domes ). Based on previous researches, eight typical hydrocarbon reservoirs or oil and gas bearing structures in block S, including Ashikol S., Kaganai, Sarly S., Taskuduk, Sarykumak E., Kardasyn, Kopa and Oryskazgan, were analyzed. As a result, the characteristics of source rocks, reservoirs, cap rocks, traps, fluids, passage systems and preservation conditions were compared. The analysis of a wide range of data shows that three periods of hydrocarbon accumulation exist within the Post-Salt Strata. They are the period from later Triassic to the end of early Jurassic, the end of the late Jurassic as well as the period from late Cretaceous to Eogene, respectively. The control factors on hydrocarbon reservoirs were found. It is shown that salt windows are the key to hydrocarbon accumulation, reservoirs control the distribution of hydrocarbon reservoirs, and faults also have a great influence on the distribution of hydrocarbon reservoirs. Eight kinds of hydrocarbon accumulation models were established. All above results provide a scientific guidance for the next oil and gas exploration in block S.

Characteristics of Source Kitchen and Hydrocarbon Generation in Banqiao Sag, Bohaiwan Basin

Science & Technology Review. 2010, 28 (06): 78-82. ;  doi:
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Abstract ( 510 )
Banqiao sag is the most exceptional feature of the Mesozoic and Cenozoic lacustrine basins in eastern China. Gas to Oil Ratio(GOR) of the present reservoirs ranges from 300m3/t to 3000m3/t, with most of reservoirs saturated or supersaturated with gas. Based on rock-Eval data and logging data, source kitchen characteristics were evaluated. Effective source rocks chiefly lie in the first and the third members of Shahejie formation, which are of types II2-III. Total organic carbonranges from 1% to 2%, which corresponds to Hydrocarbon Index(HI) of from 200mg/g to 350 mg/g. The mature depth of the source rock is below 3600~3800m. Consequently, characteristics and components of the hydrocarbon generation and expulsion can be calculated. Significant hydrocarbon expulsion begins when the transformation rate is about 30% and vitrinite reflectance is more than 0.8%. GORs of the hydrocarbon expulsion from the first and the third members of Shahejie formation are over 600m3/t and 222m3/t, respectively, which is highly consistent with the property of the present reservoirs. The analyses of more regions in eastern China show that the initial hydrogen index(HIo) and the initial total organic carbon are key factors to control GOR of reservoirs. Most of gases trapped in Banqiao sag are attributed to the humic source rock.

Interannual Variations of Intraseasonal Oscillation Pattern of OLR in Rainy Seasons in East Asia

Science & Technology Review. 2010, 28 (06): 83-87. ;  doi:
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Abstract ( 497 )
Observational data of the Outgoing Longwave Radiation(OLR) from May to August during the period of 1979—2005 were analyzed to investigate the spatial and temporal characteristics of principal Intraseasonal Oscillation(ISO) patterns and theirs interannual variations over East Asia. The relationships between these ISO patterns were also discussed. Results indicate that there are three kinds of the notable spatial patterns: Western Pacific Dipole(WPD) pattern, Meridional Western Pacific(MWP) pattern and Middle Latitude East/Pacific(MEAP) pattern. It is found that these patterns are mainly of periodic oscillations of 10~20, 20~30 and 30~70 days, and the interannual variations of the intensity are predominant, which are associated with the heating forcing over East Asia monsoon region and nonlinear atmospheric interaction. For different time scales, the variations between the principal ISO modes of WPD pattern are independent processes, but the interactions between the principal ISO modes of MWP and MEAP patterns are dominant. These findings may have implications in improving extended-range weather forecasting for 10~30 days in East Asia summer.

M/OD Failure Risk Assessment System and Its Calibration

Science & Technology Review. 2010, 28 (06): 88-92. ;  doi:
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Abstract ( 721 )
The importance of M/OD failure risk assessment for spacecrafts design is analyzed. A graphical user interface technology based M/OD Risk Assessment System (MODRAS) is developed. It's frame chart of M/OD failure risk assessment system is presented, including two modules of orbital debris risk assessment and meteoroid risk assessment. Each module consists of functional modules for M/OD environment, the spacecraft geometry modeling, impact probability analysis, failure probability computing module, spacecraft shield design, etc. These functional modules are shared except the environment module. That is to say, they can be used in both orbital debris and meteoroid environment risk assessment. The system is calibrated by three standard cases of IADC specified. The results show that the computing precision of MODRAS is very good with precisions of similar software in different countries, such as BUMPER, ESABASE, MDPANTO and MODAOST. The discrepancy of failure number of MODRAS and BUMPER is less than 4% in the meteoroid environment. And the maximum discrepancy is 8% in the orbital debris environment. Therefore, the analytic precision of MODRAS is calibrated. The distribution of failure particles in the surface of cube, sphere and simple space station are given.

Comparative Analysis of the Organic Composition in the Exhaust Fumes Between Dual Fuel Autombiles and Gasoline Vehicles

Science & Technology Review. 2010, 28 (06): 93-97. ;  doi:
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Abstract ( 1278 )
This paper studies exhaust fumes of environment friendly dual fuel automobiles. Samples were collected from taxies fueled by natural gas, such as Shanghai Volkswag?觕n, Citr?觕n, Beijing Hyundai and from other vehicles powered by 93# gasoline in Lanzhou city. Organic matters of the two groups were analyzed, respectively, with GC/MS. The results show that there are 9 olefine, 3 alkane and 6 benzene in the exhaust fumes of Natural Gas Vehicles (NGV); and 9 olefine, 3 alkane, 22 benzene and 4 Polycyclic Aromatic Hydrocarbon(PAH) in the exhaust fumes of gasoline vehicles. Obviously, the exhaust fumes from Natural Gas Vehicles(NGV) contain few carcinogenic benzene substances and PAHs, as compared with those in waste gas from petrol-powered cars.

Effect of Submicron Dust Charging and Coagulation on Efficiency of ESP in the High Flow

Science & Technology Review. 2010, 28 (06): 98-102. ;  doi:
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Abstract ( 832 )
Due to the inefficiency of collecting submicron dust, the current electrostatic precipitator(ESP) suffers from disadvantages of great size and much consumed energy. This paper proposes to put the ion source and the charging and coagulation equipment in the flue, to secure a high ion transportation rate with high particle momentum. The results show that the ion density is increased with the increase of the electric field intensity. In the condition of high momentum, the ion density reaches 1.97×109/cm3, 2~3 orders of magnitude higher than that of ESP. Rectangular powered electrodes are shown to be better than circular powered electrodes. The prickle powered electrodes, with low corona onset voltage, consume less power and generate ions of high density in a stable way. So the prickle powered electrodes are the best choice. Median-particle-size of 0.2μm silicon powder, median-particle-size of 6μm talcum powder and the mixed powder of silicon powder and talcum powder were charged and coagulated to big particles. The efficiency of ESP is significantly improved. A charging system equal to a room of ESP can be saved. The problem of low efficiency of the current ESP can be solved without the need to increase the rooms of ESP and to change the running matter and the parameters, but only by making use of the high momentum of charging particles in the flue.
Reviews

The Embryo Fossils from the Neoproterozoic Weng'an Biota in Guizhou Province (South China)

YIN Zongjun;ZHU Maoyan
Science & Technology Review. 2010, 28 (06): 103-111. ;  doi:
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Abstract ( 1308 )
The Ediacaran Weng'an biota from the phosphorite of the upper Doushantuo Formation(635~551Ma) at Weng'an, Guizhou Province(South China) consists of cyanobacteria, acritarchs, multicellular algae, and abundant metazoan eggs and embryos, together with few animal larvae and adults. These putative phosphatized animal embryo fossils with cellular structures preserved in three-dimensional structures have shed unprecedented paleontological light on the origin and early evolution of metazoans. Present paper reviews significant progresses of researches on the embryo fossils of the Weng'an Biota during the past decade. Up to date, there are five types of embryos with different cleavage patterns that have been identified through various advanced techniques, especially the application of nondestructive 3D imaging by synchrotron radiation X-ray phase contrast microtomography(SRX-PC-μCT). As a most challenging field in the frontier of paleontology, more significant discoveries and information about these early embryo fossils are expected through the investigations on new materials and applications of new techniques such as SRX-PC-μCT. Recent hypothesis that the large acanthomorphic acritarchs thieved during the same time of the Weng'an Biota are the diapause embryos is an example.

Preparation and Photocatalytic Properties of Nanometer Titania Loaded with Fluorine: A Review

Science & Technology Review. 2010, 28 (06): 112-115. ;  doi:
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Abstract ( 530 )
The intrinsic properties of titanium dioxide could be modified by fluorine doping into crystal lattice, including the photocurrent charge carrier immigration property, the specific surface area, the channel structure, the surface acidity, and others. These changes could influence the recombination of photoinduced electron-hole pairs and the absorption of the parent compound, and thus greatly improve the photocatalysis activity of titanium dioxide, especiallly, under irradiation of ultraviolet light. Although fluorine doping of titanium dioxide was prepared in the laboratory scale, some factors may influence the nano-particle's crystal structure and surface properties, such as the preparation method, the annealing temperature, the precursors, the stoichiometric equivalent, etc. Under these influences, the nanometer photocatalyzer may show different photocatalysis activities, which would be embodied in the rutile phase transformation, the formation of Ti3+, the increase of quantum yield, the change of absorbability (such as surface polarity), and so forth. Thus the photocatalysis efficiency depends strongly on the methods of fluorine doping , the dosage level and the light source. This paper presents a general review of preparation and photocatalysis activity of fluorine doped titanium dioxide with respect to catalyst preparation; phase transformation process and the mineralization of parent compounds.

Science & Technology Review. 2010, 28 (06): 116-116. ;  doi:
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科技评论

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Focus

Science & Technology Review. 2010, 28 (06): 118-119. ;  doi:
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主编心语

Science & Technology Review. 2010, 28 (06): 125-125. ;  doi:
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走向职场

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